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Sample records for acquired methicillin-resistant staphylococcus

  1. CHARACTERIZATION OF HOSPITAL ACQUIRED METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS

    Preethi. B.M; J.Vimalin Hena

    2012-01-01

    Methicillin Resistant Staphylococcus aureus (MRSA) strains have emerged as one of the most important nosocomial pathogens. The MRSA can cause a wide range of diseases, which is associated with its production to large number of extracellular toxins and other virulence factors. The diseases are toxic shock syndrome, scalded skin syndrome and food poisoning. Hospital-acquired MRSA (HA-MRSA) in persons who have had frequent or recent contact with hospitals or healthcare facilities within the prev...

  2. Postpartum Mastitis and Community-acquired Methicillin-resistant Staphylococcus aureus

    Reddy, Pavani; Qi, Chao; Zembower, Teresa; Noskin, Gary A.; Bolon, Maureen

    2007-01-01

    This single-center, case-control study documents a relative increase in methicillin resistance among 48 cases of Staphylococcus aureus–associated postpartum mastitis during 1998–2005. Of 21 cases with methicillin resistance, 17 (81%) occurred in 2005. Twenty (95%) isolates contained the Staphylococcus cassette chromosome mec type IV gene; this suggests that the increase is due to community-acquired methicillin-resistant Staphylococcus aureus.

  3. Community-Acquired Methicillin-Resistant "Staphylococcus aureus": Considerations for School Nurses

    Alex, Aniltta; Letizia, MariJo

    2007-01-01

    Methicillin-resistant "Staphylococcus aureus" (MRSA) is a disease-causing organism that has been present in hospital settings since the 1960s. However, a genetically distinct strain of MRSA, called community-acquired methicillin-resistant "Staphylococcus aureus" (CA-MRSA), has emerged in recent years in community settings among healthy…

  4. CHARACTERIZATION OF HOSPITAL ACQUIRED METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS

    Preethi. B.M

    2012-12-01

    Full Text Available Methicillin Resistant Staphylococcus aureus (MRSA strains have emerged as one of the most important nosocomial pathogens. The MRSA can cause a wide range of diseases, which is associated with its production to large number of extracellular toxins and other virulence factors. The diseases are toxic shock syndrome, scalded skin syndrome and food poisoning. Hospital-acquired MRSA (HA-MRSA in persons who have had frequent or recent contact with hospitals or healthcare facilities within the previous year, has recently undergone an invasive medical procedure, or is immunocompromised. Mostly HA-MRSA are transmitted most frequently through direct skin-to-skin contact or contact with shared items or surfaces that have come into contact with someone else’s colonized or infected skin. Panton Valentine Leukocidin (PVL is a biocomponent toxin has been shown to induce lysis of host defence cells. The absence of the PVL gene confirms the MRSA as HA-MRSA. Slime layer plays a remarkable role in bacterial colonization of exterior surfaces by adhesion and production of slime factor plays an important role in antibiotic resistance. Beta lactamases render bacteria resistant to beta-lactam antibiotics by hydrolyzing the beta lactam ring of penicillin’s and cephalosporins.There is a linear correlation between beta-lactamase activity and the level of resistance of bacteria to penicillins. The phage groups II and III were present in hospital acquired MRSA which colonizes on the normal skin and enter the body through cut/wound or by fracture and cause osteomyelitis and bacterial arthritis. Bacteriophage typing of MRSA strains is an epidemiological marker and is a successful method in strain characterization.

  5. Emerging Community-Acquired Methicillin-Resistant Staphylococcus Aureus Pneumonia

    Dragana Orlovic

    2009-04-01

    Full Text Available Background: Methicillin-resistant Staphylococcus aureus (MRSA has been an important nosocomial pathogen worldwide for more than four decades. Community-acquired MRSA infections, generally occurring in previously healthy persons without recognizable risk factors for health care setting-related MRSA, are emerging as serious clinical and public health concerns. The most frequent of these community-based infections include skin and soft tissue infections and necrotizing pneumonias. A majority of causative community-acquired MRSA (CA-MRSA isolates are associated with genes that encode the virulence factor, Panton-Valentine leukocidin (PVL toxin. Aims & Objectives: To describe six cases of CA-MRSA pneumonia recently admitted to our community hospital in Florida, and discuss the epidemiology, clinical features, and management of these expanding infections. Methods/Study Design: The medical records of six patients with radiographically-confirmed pneumonia and positive sputum cultures for MRSA at the time of hospitalization at the Lawnwood Regional Medical Center and Heart Institute, Fort Pierce, Florida, from December 2006 through January 2007, were retrospectively reviewed. All patients were seen by one of the authors (DO, an infectious diseases consultant. Lawnwood Regional Medical Center is a 341-bed, acute care institution and regional referral center for four counties of Treasure Coast, FL. The hospital institution review board gave permission for this study. Results/Findings: Six patients (5 men, 1 woman with CA-MRSA pneumonia were identified. The mean patient age was 57 years (range, 32-79 years. Three patients had no history of previous hospital admission, while two patients had been last hospitalized two years prior to the study admission. Three elderly patients had known co-morbidities predisposing to pneumonia including carcinoma of the lung (2 patients, and cirrhosis, diabetes mellitus, chronic renal failure, COPD, and cardiomyopathy (1

  6. An Outbreak of Community-Acquired Foodborne Illness Caused by Methicillin-Resistant Staphylococcus aureus

    Jones, Timothy F.; Kellum, Molly E.; Porter, Susan S.; Bell, Michael; Schaffner, William

    2002-01-01

    Infections with methicillin-resistant Staphylococcus aureus (MRSA) are increasingly community acquired. We investigated an outbreak in which a food handler, food specimen, and three ill patrons were culture positive for the same toxin-producing strain of MRSA. This is the first report of an outbreak of gastrointestinal illness caused by community-acquired MRSA.

  7. Comparative Molecular Analysis of Community- or Hospital-Acquired Methicillin-Resistant Staphylococcus aureus

    Fey, P. D.; Saïd-Salim, B.; Rupp, M. E.; Hinrichs, S H; Boxrud, D. J.; Davis, C C; Kreiswirth, B N; Schlievert, P M

    2003-01-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is a growing public health concern that has been associated with pediatric fatalities. It is hypothesized that the evolution of CA-MRSA is a recent event due to the acquisition of mec DNA by previously methicillin-susceptible strains that circulated in the community. This study investigated the genetic relatedness between CA-MRSA, hospital-associated MRSA (HA-MRSA), and nonmenstrual toxic shock syndrome (nmTSS) isolates....

  8. A Comparative Analysis of Community Acquired and Hospital Acquired Methicillin Resistant Staphylococcus Aureus

    P R, Vysakh; M, Jeya

    2013-01-01

    Purpose: Staphylococcus aureus has developed resistance against most of the therapeutic agents. The most notable example of this phenomenon was the emergence of Methicillin resistant Staphylococcus aureus (MRSA). We are reporting the prevalence and the antibiotic susceptibility pattern of the MRSA isolates from a tertiary care hospital.

  9. Acute haematogenous community-acquired methicillin-resistant Staphylococcus aureus osteomyelitis in an adult: Case report and review of literature

    Dhanoa Amreeta; Singh Vivek; Mansor Azura; Yusof Mohd; Lim King-Ting; Thong Kwai-Lin

    2012-01-01

    Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA) has of late emerged as a cause of community-acquired infections among immunocompetent adults without risk factors. Skin and soft tissue infections represent the majority of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) clinical presentations, whilst invasive and life-threatening illness like necrotizing pneumonia, necrotizing fasciitis, pyomyositis, osteomyelitis and sepsis syndrome are less comm...

  10. Prevalence and invasiveness of community-acquired methicillin-resistant Staphylococcus aureus: A meta-analysis

    Shipeng Li; Juan Li; Yanhong Qiao; Xue Ning; Ting Zeng; Xuzhuang Shen

    2014-01-01

    Background: Reports suggest that the prevalence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has increased, and that CA-MRSA is more virulent than healthcare-associated (HA)-MRSA. Aims: The aim of this study is to gain a better understanding of the invasiveness and prevalence of CA-MRSA in patients; we systematically reviewed the literature by conducting a meta-analysis. Materials and Methods: We searched the MEDLINE and PUBMED databases from the year these data...

  11. Facet joint septic arthritis due to community acquired methicillin resistant Staphylococcus aureus (MRSA) - A case report.

    Purushothaman, Rajesh; Inassi, Jojo; Marthya, Anwar

    2015-10-01

    Septic arthritis of facet joint (SAFJ) is extremely rare. Only about sixty cases have been reported so far. A single case of SAFJ in a series of 491 cases of spinal infections was first reported by David-Chaussé in 1981. A case report of SAFJ was published by Halpin in 1987. With the growing availability and use of MRI, more and more cases are being reported. The most common organism that causes SAFJ is Staphylococcus aureus. We are reporting a case of SAFJ caused by community acquired, methicillin resistant S aureus (MRSA) successfully treated by Linezolid. PMID:26719620

  12. Prevalence of Methicillin Resistant Staphylococcus aureus in pyogenic community and hospital acquired skin and soft tissues infections

    Objective: To determine the percentage and frequency of Methicillin Resistant Staphylococcus aureus in community and hospital-acquired pyogenic skin and soft tissue infections. Methods: The descriptive cross-sectional study was conducted at the Dermatology Department of Combined Military Hospital, Abbottabad, from June 2009 to March 2010, and comprised 144 community-acquired and 54 hospital-acquired skin and soft tissue infections. Pus swabs from the infected lesions one from each individual were sent to laboratory for culture and sensitivity tests. Methicillin resistance was detected by 1 (mu) g oxacillin disk. Organisms were labelled methicillin-resistant once the inhibition zone for oxocillin was less than 10 mm. Data analysis was done by using SPSS 20. Results: Of the 198 patients in the study, 98(49.5%) were males and 100(50.5%) were females, with an overall mean age of 33.7+-14.8144 years. There were 144(72.72%) community-acquired infections and 54(27.27%) had hospital-acquired infections. Community-acquired Methicillin Resistant Staphylococcus aureus numbered 40(27.8%) and hospital-acquired ones numbered 26(48.1%). Conclusion: Prevalence of Methicillin Resistant Staphylococcus aureus in community and hospital-acquired pyogenic skin and soft tissue infections was high. (author)

  13. Community-acquired methicillin-resistant Staphylococcus aureus pyomyositis with myelitis: A rare occurrence with diverse presentation

    Kulkarni Girish

    2009-12-01

    Full Text Available Staphylococcus aureus is the most common bacterial pathogen implicated in pyomyositis. There are increasing reports of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA infections. The present case report brings out the diverse clinical manifestations of MRSA infection in the form of paraspinal pyomyositis, myelitis, spinal osteomyelitis, and pneumonia. Molecular typing of the organism confirmed the diagnosis. Patient was successfully treated with vancomycin and surgical drainage. Consideration of the possibility of methicillin-resistance and appropriate antibiotic selection is vital in the treatment of serious community-acquired staphylococcal infections.

  14. Community-acquired methicillin-resistant Staphylococcus aureus: What do we need to know?

    Witte, Wolfgang

    2009-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a matter of concern worldwide, in particular in the USA. For the analysis of emergence and spread, clear definitions based on epidemiological origin are needed for discrimination between CA-MRSA, healthcare-associated community MRSA, and healthcare-associated MRSA (HA-MRSA). Although its role in pathogenesis is currently under debate, the capability for Panton-Valentine leukocidin formation is associated wit...

  15. Successful reduction of hospital-acquired methicillin-resistant Staphylococcus aureus in a urology ward: a 10-year study

    Tatokoro, Manabu; Kihara, Kazunori; Masuda, Hitoshi; Ito, Masaya; Yoshida, Soichiro; Kijima, Toshiki; Yokoyama, Minato; Saito, Kazutaka; Koga, Fumitaka; Kawakami, Satoru; Fujii, Yasuhisa

    2013-01-01

    Background To eradicate hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) using a stepwise infection control strategy that includes an avoidance of antimicrobial prophylaxis (AMP) based on surgical wound classification and an improvement in operative procedures in gasless single-port urologic surgery. Methods The study was conducted at an 801-bed university hospital. Since 2001, in the urology ward, we have introduced the stepwise infection control strategy. In 2007, survei...

  16. Community-acquired methicillin-resistant Staphylococcus aureus in a Malaysian tertiary centre.

    Rashid, Zetti Zainol; Bahari, Norazlah; Othman, Amizah; Jaafar, Roslinda; Mohamed, Nurul Azmawati; Jabbari, Idimaz; Sulong, Anita; Hashim, Rohaidah; Ahmad, Norazah

    2013-01-01

    Abstract. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is a pathogen recognized to be distinct in both phenotype and genotype from hospital-acquired MRSA. We have identified CA-MRSA cases in Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia, including their antibiotic susceptibility patterns and genotypic characteristics. Cases were identified during January to December 2009 from routine clinical specimens, where culture and antibiotic susceptibility results yielded pauci-resistant MRSA isolates suspected as being CA-MRSA. The patients' clinical data were collected and their specimens were sent for molecular confirmation and analysis. Five cases of CA-MRSA were identified, which had a multi-sensitive pattern on antibiotic susceptibility tests and were resistant to only penicillin and oxacillin. All cases were skin and soft-tissue infections, including diabetic foot with gangrene, infected scalp hematoma, philtrum abscess in a healthcare worker, thrombophlebitis complicated with abscess and infected bedsore. All five cases were confirmed MRSA by detection of mecA. SCCmec typing (ccr and mec complex) revealed SCCmec type IV for all cases except the infected bedsore case. Panton-Valentine leukocidin gene was positive in all isolates. As clinical features among methicillin-sensitive Staphylococcus aureus, CA-MRSA and "nosocomial CA-MRSA" are indistinct, early recognition is necessary in order to initiate appropriate antibiotics and infection control measures. Continual surveillance of pauci-resistant MRSA and molecular analysis are necessary in order to identify emerging strains as well as their epidemiology and transmission, both in the community and in healthcare setting. PMID:23682444

  17. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA: molecular background, virulence, and relevance for public health

    MF Bonesso

    2011-01-01

    Full Text Available Staphylococcus aureus and coagulase-negative Staphylococcus (CoNS are frequently found in nosocomial environments as the main pathogen in several infections. In 1961, reports of nosocomial S. aureus resistant to methicillin, the drug of choice against penicillin-resistant strains, required new alternatives and vancomycin started being used to treat infections caused by methicillin-resistant S. aureus (MRSA. Community-acquired methicillin-resistant S. aureus (CA-MRSA was first reported in 1990 affecting patients without risk factors for infection with MRSA of hospital origin. MRSA of community origin harbor the genes responsible for the synthesis of Panton-Valentine leukocidin (PVL, a toxin associated with skin and soft tissue infections and that carries the staphylococcal cassette chromosome mec (SCCmec type IV. CA-MRSA emergence has caused great impact on the worldwide medical community since the presence of this pathogen in patients without risk factors represents a high risk to public health.

  18. Community-acquired Methicillin-resistant Staphylococcus Aureus (CA-MRSA):A Public Health Concern in Athletic Settings

    Lindsay K. Drewes

    2008-01-01

    @@ Background Methicillin-resistant Staphylococcus aureus (MRSA) is a type of bacteria, commonly manifesting itself in the form of skin infections, and resistant to beta-lactum antibiotics[2]. These infections were seen in hospital settings starting in the 1960s in patients that had recently been hospitalized or undergone a medical procedure[3]. In the 1980s reports were first published in the literature of MRSA acquired in otherwise healthy individuals from community settingsr[4,5]. An increased occurrence of community-associated Methicillin-resistant Staphylococcus aureus (CA-MRSA) has been on the rise since the late 1990s and manifests itself as a skin infection in populations without other previously known risk factors[6-8].

  19. Prevalence and invasiveness of community-acquired methicillin-resistant Staphylococcus aureus: A meta-analysis

    Shipeng Li

    2014-01-01

    Full Text Available Background: Reports suggest that the prevalence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA has increased, and that CA-MRSA is more virulent than healthcare-associated (HA-MRSA. Aims: The aim of this study is to gain a better understanding of the invasiveness and prevalence of CA-MRSA in patients; we systematically reviewed the literature by conducting a meta-analysis. Materials and Methods: We searched the MEDLINE and PUBMED databases from the year these databases were established to January 2013. Results: The pooled CA-MRSA prevalence among 50,737 patients from 33 studies was 39.0% (range, 30.8-47.8%. The pooled CA-MRSA prevalence rates among pediatric and adult patients with MRSA infection were 50.2% (range, 37.5-62.8% and 42.3% (range, 16.4-73.3%, respectively. The pooled CA-MRSA prevalence rates of MRSA-infected patients in Asia, Europe, and North America were 23.1% (range, 12.0-39.8%, 37.4% (range, 21.1-56.4%, and 47.4% (range, 35.8-59.4%, respectively. Using the random effects model, we determined that the pooled odds ratio of invasive infections in CA- and HA-MRSA was 0.30 (95% confidence interval: 0.08-1.10; P = 0.07, test for heterogeneity P < 0.00001. Conclusions: The prevalence of CA-MRSA in MRSA infection varied with area and population. No difference in the ability to cause invasive infections was found between CA- and HA-MRSA. This finding challenges the view that CA-MRSA is more virulent than HA-MRSA.

  20. Antimicrobial activity of tigecycline against community-acquired methicillin-resistant Staphylococcus aureus isolates recovered from North American medical centers.

    Mendes, Rodrigo E; Sader, Helio S; Deshpande, Lalitagauri; Jones, Ronald N

    2008-04-01

    A total of 1989 community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) were susceptibility tested by broth microdilution. Pulsed-field gel electrophoresis, SCCmec type, and polymerase chain reaction for Panton-Valentine leukocidin (PVL) genes were also performed. The overall tigecycline susceptibility rate was 98.2%. Glycopeptides, quinupristin/dalfopristin, linezolid, and chloramphenicol were also active against this collection (< or =0.7% resistant). The vast majority (70.8%) of the CA-MRSA was SCCmec type IV, from which 88.4% belonged to the USA300-0114 clone and 94.7% were PVL positive. Tigecycline showed in vitro activity comparable with other highly active parenteral agents and represents an option for treating complicated infections caused by CA-MRSA. PMID:18068326

  1. Acute haematogenous community-acquired methicillin-resistant Staphylococcus aureus osteomyelitis in an adult: Case report and review of literature

    Dhanoa Amreeta

    2012-10-01

    Full Text Available Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA has of late emerged as a cause of community-acquired infections among immunocompetent adults without risk factors. Skin and soft tissue infections represent the majority of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA clinical presentations, whilst invasive and life-threatening illness like necrotizing pneumonia, necrotizing fasciitis, pyomyositis, osteomyelitis and sepsis syndrome are less common. Although more widely described in the pediatric age group, the occurrence of CA-MRSA osteomyelitis in adults is an uncommonly reported entity. Case presentation We describe an invasive CA-MRSA infection in a 28 year-old previously healthy male, manifesting with bacteraemia, osteomyelitis of femur, pyomyositis and septic arthritis of the knee. Initially a preliminary diagnosis of osteosarcoma was suggested by imaging studies and patient underwent a bone biopsy. MRSA was subsequently isolated from blood cultures taken on day of admission, bone, tissue and pus cultures. Incision and drainage of abscess was performed and patient was treated with vancomycin, with fusidic acid added later. It took 6 months for the inflammatory markers to normalize, warranting 6-months of anti-MRSA therapy. Patient was a fervent deer hunter and we speculate that he acquired this infection from extensive direct contact with deer. Molecular characterization of this isolate showed that it belonged to multilocus sequence type (MLST ST30 and exhibited the staphylococcal chromosome cassette mec (SCCmec type IV, staphylococcus protein A (spa type t019, accessory gene regulator (agr type III and dru type dt10m. This strain harbored Panton-Valentine leukocidin (pvl genes together with 3 other virulent genes; sei (enterotoxin, hlg (hemolysin and fnbA (fibronectin binding protein. Conclusion This case study alerts physicians that beyond the most commonly encountered skin and soft tissue

  2. Sepse por Staphylococus aureus resistente à meticilina adquirida na comunidade no sul do Brasil Sepsis due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil

    Luciane Cristina Gelatti

    2009-08-01

    Full Text Available Staphylococcus aureus resistente à meticilina foi inicialmente descrito como um típico microrganismo adquirido em infecções nosocomiais. No entanto, nos últimos anos Staphylococcus aureus resistente à meticilina adquirido na comunidade é causa de infecções de pele e tecidos moles, mas infecções graves como pneumonia e sepse podem ocorrer. Este relato descreve um caso de sepse em criança, complicado com pneumonia secundária a lesão em partes moles por Staphylococcus aureus resistente à meticilina adquirido na comunidade no Sul do Brasil. O paciente foi atendido em Unidade de Emergência com história de ferimento provocado por trauma em membro inferior que evoluiu para celulite, pneumonia e sepse.Methicillin-resistant Staphylococcus aureus was initially described as a typical microorganism acquired in nosocomial infections. However, over recent years, community-acquired methicillin-resistant Staphylococcus aureus has been a cause of skin and soft-tissue infections. Serious infections such as pneumonia and sepsis can also occur. This report describes a case of sepsis in a child that was complicated by pneumonia secondary to soft tissue lesions that were due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil. The patient was attended at the Emergency Unit with a history of injury caused by lower-limb trauma that evolved to cellulitis, pneumonia and sepsis.

  3. Radiological findings of community-acquired methicillin-resistant and methicillin-susceptible staphylococcus aureus pediatric pneumonia in Hawaii

    Erdem, Guliz; Bergert, Lora; Len, Kyra; Melish, Marian [University of Hawaii, John A. Burns School of Medicine, Department of Pediatrics, Honolulu, HI (United States); Kon, Kevin; DiMauro, Robert [Kapiolani Medical Center for Women and Children, Department of Radiology, Honolulu, HI (United States)

    2010-11-15

    Community-acquired Staphylococcus aureus (CA-SA) infections are common among pediatric patients in Hawaii. We wanted to characterize the radiological features of methicillin-susceptible (CA-MSSA) and methicillin-resistant (CA-MRSA) staphylococcal pneumonia in Hawaiian children. We retrospectively reviewed medical records and imaging studies of children with SA pneumonia identified from 1996 through 2007. Of 40 children, 26 (65%) had CA-MRSA pneumonia and 14 patients (35%) had CA-MSSA pneumonia. CA-MRSA patients were significantly younger than CA-MSSA patients (65% younger than 1 year vs. 36% older). In a majority (62%) of CA-MRSA patients, the consolidation was unilateral; in most of the CA-MSSA cases (79%), the consolidation was bilateral. Fifty percent of the patients with CA-MRSA and 21% of those with CA-MSSA had pneumatoceles (P = 0.1). CA-MRSA patients more commonly had pleural effusions (85% vs. 64% for CA-MSSA) and pleural thickening (50% vs. 36% for CA-MSSA). This case series describes the radiologic characteristics of CA-MRSA and CA-MSSA pneumonia in children in a highly endemic area. We found that CA-MRSA pneumonias are unilateral in a majority of pediatric pneumonia cases, are more common in children 1 year or younger, and have higher rates of complications in comparison to CA-MSSA patients. (orig.)

  4. Comparing the epidemiology of hospital-acquired methicillin-resistant Staphylococcus aureus clone groups in Alberta, Canada.

    Bruzzese, S; Bush, K; Leal, J; Kim, J; Vickers, D M; Rusk, A; Fathima, S; Li, V; Chui, L; Louie, M; Henderson, E

    2016-07-01

    Patients with methicillin-resistant Staphylococcus aureus (MRSA) clones, which were traditionally seen in the community setting (USA400/CMRSA7 and USA300/CMRSA10), are often identified as hospital-acquired (HA) infections using Infection Prevention and Control (IPC) surveillance definitions. This study examined the demographics and healthcare risk factors of patients with HA-MRSA to help understand if community MRSA clones are from a source internal or external to the hospital setting. Despite USA300/CMRSA10 being the predominant clone in Alberta, hospital clones (USA100/CMRSA2) still dominated in the acute care setting. In the Alberta hospitalized population, patients with USA400/CMRSA7 and USA300/CMRSA10 clones were significantly younger, had fewer comorbidities, and a greater proportion had none or ambulatory care-only healthcare exposure. These findings suggest that there are two distinct populations of HA-MRSA patients, and the patients with USA400/CMRSA7 and USA300/CMRSA10 clones identified in hospital more greatly resemble patients affected by those clones in the community. It is possible that epidemiological assessment overidentifies HA acquisition of MRSA in patients unscreened for MRSA on admission to acute care. PMID:26947456

  5. Radiological findings of community-acquired methicillin-resistant and methicillin-susceptible staphylococcus aureus pediatric pneumonia in Hawaii

    Community-acquired Staphylococcus aureus (CA-SA) infections are common among pediatric patients in Hawaii. We wanted to characterize the radiological features of methicillin-susceptible (CA-MSSA) and methicillin-resistant (CA-MRSA) staphylococcal pneumonia in Hawaiian children. We retrospectively reviewed medical records and imaging studies of children with SA pneumonia identified from 1996 through 2007. Of 40 children, 26 (65%) had CA-MRSA pneumonia and 14 patients (35%) had CA-MSSA pneumonia. CA-MRSA patients were significantly younger than CA-MSSA patients (65% younger than 1 year vs. 36% older). In a majority (62%) of CA-MRSA patients, the consolidation was unilateral; in most of the CA-MSSA cases (79%), the consolidation was bilateral. Fifty percent of the patients with CA-MRSA and 21% of those with CA-MSSA had pneumatoceles (P = 0.1). CA-MRSA patients more commonly had pleural effusions (85% vs. 64% for CA-MSSA) and pleural thickening (50% vs. 36% for CA-MSSA). This case series describes the radiologic characteristics of CA-MRSA and CA-MSSA pneumonia in children in a highly endemic area. We found that CA-MRSA pneumonias are unilateral in a majority of pediatric pneumonia cases, are more common in children 1 year or younger, and have higher rates of complications in comparison to CA-MSSA patients. (orig.)

  6. Invasive Community-Acquired Methicillin-Resistant Staphylococcus aureus in a Japanese Girl with Disseminating Multiple Organ Infection: A Case Report and Review of Japanese Pediatric Cases

    Ryuta Yonezawa; Tsukasa Kuwana; Kengo Kawamura; Yasuji Inamo

    2015-01-01

    Pediatric invasive community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infection is very serious and occasionally fatal. This infectious disease is still a relatively rare and unfamiliar infectious disease in Japan. We report a positive outcome in a 23-month-old Japanese girl with meningitis, osteomyelitis, fasciitis, necrotizing pneumonia, urinary tract infection, and bacteremia due to CA-MRSA treated with linezolid. PCR testing of the CA-MRSA strain was positive for PVL...

  7. Analysis of the Clinical Characteristics and Antibiotics Resistance of Community-acquired Methicillin-resistant Staphylococcus aureus

    章税锋; 徐志江; 王林峰

    2004-01-01

    The purpose of this investigation is to study the clinical characteristics of infections by community-acquired methicillin-resistant Staphylococcus aureus (MRSA) and the condition of antibiotics resistance of the clinical isolates in order to guide for the rational use of antibiotics. With the clinical isolates from cases of hospital-acquired MRSA at the same period as contro|s, the clinical characteristics of infections by community-acquired MRSA in Hangzhou area and the pattern of non-β-lactamase antibiotics resistance were determined in this study. It was found that the average age of patients with community-acquired MRSA infections was 30.89 + 13.3, in comparison with those of the hospital-acquired patients of 56.0 + 11.8, appearing to be younger than those of the latter, and the former showing no any basic illness. Both of the former and the latter were sensitive to vancomycin ( 100% vs 100% ), and they had the same degrees of sensitivity to rifampicin, fosfomycin, and STM/TMP (86.8%vs88.1%, P>0.05; 81.6% vs 82.9%, P>0.05; and 52.6% vs 61.9%, P>0.05, respectively). The former was more sensitive to netimycin, chndamycin, erythromycin and minocycline than those of the latter (73.7% vs50.5%, P<0.01; 60.5% vs45.7%, P<0.05; 28.9% vs 11.4%, P<0.01; and81.6% vs58.6%, P<0.01 respectively). Meanwhile, the incidence of multi-resistant strain of isolates in the former was significantly lowerthan that of the latter (31.6% vs 81.0%, P < 0.01). In conclusion, it appears that the strains of clinical isolates isolated from patients with the community-acquired MRSA infections show different clinical characteristics and antimicrobial susceptibility in comparison with those of the hospital-acquired cases of infection, and this necessitates an alteration in the chemotherapy of infections suspected to be caused by community-acquired MRSA.

  8. Antimicrobial (Drug) Resistance: Methicillin-Resistant Staphylococcus aureus (MRSA)

    ... Marketing Share this: Main Content Area Methicillin-Resistant Staphylococcus aureus (MRSA) During the past four decades, methicillin-resistant Staphylococcus aureus , or MRSA, has evolved from a controllable ...

  9. Curcumin Reverse Methicillin Resistance in Staphylococcus aureus

    Su-Hyun Mun; Sung-Bae Kim; Ryong Kong; Jang-Gi Choi; Youn-Chul Kim; Dong-Won Shin; Ok-Hwa Kang; Dong-Yeul Kwon

    2014-01-01

    Curcumin, a natural polyphenolic flavonoid extracted from the rhizome of Curcuma longa L., was shown to possess superior potency to resensitize methicillin-resistant Staphylococcus aureus (MRSA) to antibiotics. Previous studies have shown the synergistic activity of curcumin with β-lactam and quinolone antibiotics. Further, to understand the anti-MRSA mechanism of curcumin, we investigated the potentiated effect of curcumin by its interaction in diverse conditions. The mechanism of anti-MRSA ...

  10. Increased prevalence of methicillin-resistant Staphylococcus aureus nasal colonization in household contacts of children with community acquired disease

    Rafee Yaseen

    2012-02-01

    Full Text Available Abstract Background To measure Methicillin-resistant Staphylococcus aureus (MRSA nasal colonization prevalence in household contacts of children with current community associated (CA-MRSA infections (study group in comparison with a group of household contacts of children without suspected Staphylococcus aureus infection (a control group. Methods This is a cross sectional study. Cultures of the anterior nares were taken. Relatedness of isolated strains was tested using pulse field gel electrophoresis (PFGE. Results The prevalence of MRSA colonization in the study group was significantly higher than in the control group (18/77 (23% vs 3/77 (3.9%; p ≤ 0.001. The prevalence of SA colonization was 28/77 (36% in the study group and 16/77 (21% in the control group (p = 0.032. The prevalence of SA nasal colonization among patients was 6/24 (25%; one with methicillin-susceptible S. aureus (MSSA and 5 with MRSA. In the study (patient group, 14/24 (58% families had at least one household member who was colonized with MRSA compared to 2/29 (6.9% in the control group (p = 0.001. Of 69 total isolates tested by PFGE, 40 (58% were related to USA300. Panton-Valetine leukocidin (PVL genes were detected in 30/52 (58% tested isolates. Among the families with ≥1 contact colonized with MRSA, similar PFGE profiles were found between the index patient and a contact in 10/14 families. Conclusions Prevalence of asymptomatic nasal carriage of MRSA is higher among household contacts of patients with CA-MRSA disease than control group. Decolonizing such carriers may help prevent recurrent CA-MRSA infections.

  11. Invasive Community-Acquired Methicillin-Resistant Staphylococcus aureus in a Japanese Girl with Disseminating Multiple Organ Infection: A Case Report and Review of Japanese Pediatric Cases

    Ryuta Yonezawa

    2015-01-01

    Full Text Available Pediatric invasive community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA infection is very serious and occasionally fatal. This infectious disease is still a relatively rare and unfamiliar infectious disease in Japan. We report a positive outcome in a 23-month-old Japanese girl with meningitis, osteomyelitis, fasciitis, necrotizing pneumonia, urinary tract infection, and bacteremia due to CA-MRSA treated with linezolid. PCR testing of the CA-MRSA strain was positive for PVL and staphylococcal enterotoxin b and negative for ACME. SCC mec was type IVa. This case underscores the selection of effective combinations of antimicrobial agents for its treatment. We need to be aware of invasive CA-MRSA infection, which rapidly progresses with a serious clinical course, because the incidence of the disease may be increasing in Japan.

  12. Changing Trends in Resistance Pattern of Methicillin Resistant Staphylococcus aureus

    Kali, Arunava; Stephen, Selvaraj; Umadevi, Sivaraman; Kumar, Shailesh; Joseph, Noyal Mariya; Srirangaraj, Sreenivasan

    2013-01-01

    Background: Methicillin resistance in Staphylococcus aureus is associated with multidrug resistance, an aggressive course, increased mortality and morbidity in both community and health care facilities. Monitoring of newly emerging and prevalent Methicillin Resistant Staphylococcus aureus (MRSA) strains for their resistance patterns to conventional as well as novel drugs, are essential for infection control.

  13. Nosocomial and Community-Acquired Staphylococcus Aureus Bacterimias from 1980 to 1993: Impact of Intravascular Devices and Methicillin Resistance

    J.P. Steinberg; C.C. Clarke; B.O. Hackman

    1996-01-01

    textabstractThe rate of nosocomial bacteremia due to Staphylococcus aureus has increased over the past decade, but trends in community-acquired S. aureus bacteremia are less certain. This hospital-based observational study compares nosocomial and community-acquired S. aureus bacteremias during 1980-

  14. Staphylococcus aureus methicillin-resistance mechanisms

    Petrović-Jeremić Ljiljana

    2008-01-01

    Full Text Available Background/Aim. In many hospitals in the world and in our country, the spread of methicillin-resistant Staphylococcus aureus (MRSA is so wide that nowdays vancomycin is recommended for empiric treatment of staphylococcal life threatening infections (sepsis, pneumonia instead of beta-lactam antibiotics. The aim of this study was to determine the production of beta-lactamases in hospital and community isolates of staphyloococus aureus, i. e. hospital associated MRSA (HA-MRSA and community associated MRSA (CA-MRSA, the presence of homogeneous and heterogeneous type of methicillin resistance, and border-line resistance in Staphylococcus aureus (BORSA. The aim of this study was also to determine if there was a statistically significant difference between mechanisms of resistance in HA-MRSA and CA-MRSA. Methods. A total 216 clinical Staphylococcus aureus isolates from the General Hospital in the town of Cuprija and 186 ambulance Staphylococcus aureus isolates from the community were examined for the presence of methicillin-resistance using disk-diffusion test with penicillin disk (10 ij, oxacillin disk (1 μg and cefoxitin disk (30 μg. Betalactamases production was detected by nitrocefin disk and betalactamase tablets. Determination of oxacillin minimum inhibitory concentracion (MIC was done by agar-dilution method. Results. The prevalence of HA-MRSA was 57.4%, and CA-MRSA was 17.7% (p < 0.05. There was a higher rate of heterogeneous type of resistance among clinical MRSA isolates (11.1% compared with ambulance ones (3.8% (p < 0.05. The rates of beta-lactamases production were similar among hospital associated isolates (97.5%, as well as in the community associated isolates (95.5% (p > 0.05. There were 4.6 % of BORSA hospital isolates and 3.3 % of BORSA ambulance isolates (p > 0.05. Conclusion. The frequency of MRSA isolates in hospital was significantly higher than in community, as well as the heterogeneous type of resistance. The frequency of BORSA

  15. Methicillin resistance & inducible clindamycin resistance in Staphylococcus aureus

    Soumyadeep Ghosh; Mandira Banerjee

    2016-01-01

    Background & objectives: Methicillin resistant Staphylococcus aureus (MRSA) isolates with inducible clindamycin resistance (iCR) are resistant to erythromycin and sensitive to clindamycin on routine testing and inducible clindamycin resistance can only be identified by D-test. This study was aimed to detect methicillin resistance and iCR among S. aureus isolates, effectiveness of some commonly used antibiotics and correlation between methicillin resistance and iCR. Methods: The present cro...

  16. Is methicillin-resistant Staphylococcus aureus involved in community acquired skin and soft tissue infections?: Experience from a tertiary care centre in Mumbai

    R S Phakade

    2012-01-01

    Full Text Available Background: To improve the empiric antimicrobial therapy of community-acquired (CA skin and soft tissue infections (SSTIs, it is necessary to generate data on the current spectrum and susceptibility profile of associated bacteria. CA methicillin-resistant Staphylococcus aureus (CA MRSA is increasingly being reported in SSTIs in India and globally. Aims: The present study was undertaken to determine the bacterial profile of CA-SSTIs, to know the contribution of MRSA in these infections, to determine inducible clindamycin resistance in S. aureus and to compare the resistance patterns of isolates from hospital-acquired (HA SSTIs. Materials and Methods: Eight hundred and twenty patients with CA SSTIs were prospectively studied. Pus samples were cultured and antimicrobial susceptibility pattern determined. Inducible clindamycin resistance was detected by D-test. Laboratory records were analyzed retrospectively to generate data on HA SSTIs. Results: 619 isolates were recovered in CA-SSTIs, of which S. aureus (73% and Streptococci (12% were the most common. Pseudomonas aeruginosa (28% and Acinetobacter spp (18% were the predominant HA-SSTI pathogens. Susceptibility of CA S. aureus to antibiotics tested was, penicillin (6%, co-trimoxazole (20%, ciprofloxacin (37%, cefazolin (100%, erythromycin (84%, clindamycin (97%, gentamicin (94% and fusidic acid (95%. No MRSA was found in CA SSTIs whereas 45% of HA S. aureus strains were methicillin-resistant. HA strains demonstrated significantly higher resistance as compared to their CA counterparts (P<0.001. D test was positive in 22% of CA S. aureus tested. Conclusions: In CA SSTIs, methicillin-susceptible S. aureus is the predominant pathogen. Penicillinase-resistant penicillins, clindamycin and erythromycin in that order can be used as suitable antimicrobials for empiric therapy. D test should be carried out routinely. No CA MRSA was detected in the present series.

  17. Methicillin-resistant Staphylococcus aureus: the superbug.

    Ippolito, Giuseppe; Leone, Sebastiano; Lauria, Francesco N; Nicastri, Emanuele; Wenzel, Richard P

    2010-10-01

    Over the last decade, methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged as serious pathogens in the nosocomial and community setting. Hospitalization costs associated with MRSA infections are substantially greater than those associated with methicillin-sensitive S. aureus (MSSA) infections, and MRSA has wider economic effects that involve indirect costs to the patient and to society. In addition, there is some evidence suggesting that MRSA infections increase morbidity and the risk of mortality. Glycopeptides are the backbone antibiotics for the treatment of MRSA infections. However, several recent reports have highlighted the limitations of vancomycin, and its role in the management of serious infections is now being reconsidered. Several new antimicrobials demonstrate in vitro activity against MRSA and other Gram-positive bacteria. Data from large surveys indicate that linezolid, daptomycin, and tigecycline are almost universally active against MRSA. This review will briefly discuss the epidemiology, costs, outcome, and therapeutic options for the management of MRSA infections. PMID:20851011

  18. Methicillin-resistant Staphylococcus aureus transmission

    Andersen, Leif Percival; Nielsen, Xiaohui

    2015-01-01

    increase the risk of contaminating hands, arms and the front of the uniform. Hand hygiene is therefore essential, but the use of protection gowns with long sleeves is also important in order to prevent transmission of MRSA. After culture of MRSA and implementation of specific precautions to prevent......INTRODUCTION: Even though methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of nosocomial infections, it may often be difficult to evaluate the exact route of transmission. METHODS: In this study, we describe four cases of nosocomial transmission of MRSA in a hospital with a low...... transmission of MRSA, no further transmissions were observed. FUNDING: not relevant. TRIAL REGISTRATION: The data in this study are included in the routine surveillance of MRSA at Rigshospitalet and do not form part of a trial....

  19. Evolution of methicillin-resistant Staphylococcus aureus towards increasing resistance

    Strommenger, Birgit; Bartels, Mette Damkjær; Kurt, Kevin;

    2014-01-01

    To elucidate the evolutionary history of Staphylococcus aureus clonal complex (CC) 8, which encompasses several globally distributed epidemic lineages, including hospital-associated methicillin-resistant S. aureus (MRSA) and the highly prevalent community-associated MRSA clone USA300....

  20. Incidence of community-acquired methicillin-resistant Staphylococcus aureus carrying Pantone-Valentine leucocidin gene at a referral hospital in United Arab Emirates.

    Dash, Nihar; Panigrahi, Debadatta; Al Zarouni, Mansour; Yassin, Faten; Al-Shamsi, Moza

    2014-04-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emerging pathogen in hospitalized patients worldwide. The present study was undertaken to identify CA-MRSA in hospitalized patients in a 350-bed tertiary care hospital in Sharjah, UAE over a 2-year period from January 2011 to December 2012. CA-MRSA was defined based on identification within first 48 h of admission in the hospital. Staphylococcal cassette chromosome (SCC) mec typing of the CA-MRSA isolates was carried out by multiplex polymerase chain reaction (PCR). Detection of PVL and mecA genes was done by PCR using the GenoType(®) MRSA test system (Hain Lifescience). Patient's clinical data and antimicrobial susceptibility pattern of the CA-MRSA isolates were also evaluated. Fifty seven of the 187 MRSA isolates were identified as CA-MRSA. All the CA-MRSA strains in our study belonged to SCCmecIV type and were positive for both PVL and mecA genes. The patients with CA-MRSA infections were young (median age, 32 years) and the majority of infections involved the skin and soft tissue (36%). Antimicrobial susceptibility pattern of the CA-MRSA isolates showed a better susceptibility profile to the non-beta-lactam antimicrobials with the exception of ciprofloxacin having 28% resistance. This study evidently strengthens the recent observation of an increase in CA-MRSA emergence among hospitalized patients in the UAE. PMID:23919760

  1. Influence of papain in biofilm formed by methicillin-resistant Staphylococcus epidermidis and methicillin-resistant Staphylococcus haemolyticus isolates

    Hanna Lara da Cruz Dinéas de Oliveira; Maria Emília de Castro Kling Fleming; Patrícia Vollu Silva; Geraldo Renato de Paula; Débora Omena Futuro; Guillermo Coca Velarde; Luciana Maria Ramires Esper; Lenise Arneiro Teixeira

    2014-01-01

    Methicillin-resistant Staphylococcus epidermidis (MRSE) and methicillin-resistant Staphylococcus haemolyticus (MRSHa) are important coagulase-negative staphylococci. They are often isolated from bacteremia in humans mainly due to their ability to form biofilm on the surfaces of medical devices. Papain is a complex mixture of proteolytic enzymes and peroxidases extracted from the latex of Carica papaya and it is recognized by accelerating the healing process of wounds. This study aimed to eval...

  2. Molecular characteristics of community-acquired methicillin-resistant Staphylococcus aureus strains isolated from outpatients with skin and soft tissue infections in Wuhan, China.

    Liu, Xiaoli; Liang, Jiansheng; Jiang, Yuanshan; Wang, Bin; Yuan, Hong; Zhang, Lihua; Zhou, Yanfei; Xu, Huiqiong; Zhou, Wang

    2016-06-01

    This study aims to investigate the antimicrobial susceptibility, molecular characteristics and virulence genes of community-acquired methicillin-resistant ITALIC! Staphylococcus aureus(CA-MRSA) isolates with skin and soft tissue infections (SSTIs). Outpatients with SSTIs visiting five medical and health institutions were enrolled from 2011 to 2013. Available ITALIC! S. aureus isolates were characterized by antimicrobial susceptibility testing, and detection of PVL genes. For CA-MRSA isolates, we performed typing of staphylococcal cassette chromosome ITALIC! mec(SCC ITALIC! mec), multi locus sequence typing (MLST) and carriage of 27 virulence genes. A total of 203 ITALIC! S. aureusstrains were isolated from 1400 outpatients with SSTIs, and 21 (10.3%) were CA-MRSA isolates. The positive rate of PVL genes among ITALIC! S. aureus, CA-MRSA and methicillin-susceptible ITALIC! S. aureus(MSSA) isolates were 39.4%, 71.4% and 35.7%, respectively. CA-MRSA strains had greater sensitivity to non-β-lactam antimicrobial agents. All CA-MRSA isolates belonged to SCC ITALIC! mecIV and V, accounting for 47.6% and 52.4%, respectively. ST59 was the most common lineage accounting for 76.2%; ST59-SCC ITALIC! mecIVa-PVL-positive clone was found to be the predominant clone, accounting for 38.1%. All CA-MRSA isolates were found to be positive for one or more virulence genes, 28.6% of isolates carried PVL, ITALIC! seb, ITALIC! sek, ITALIC! seq, ITALIC! hla, ITALIC! hlb, ITALIC! hldand ITALIC! hlg-2. CA-MRSA infections were relatively uncommon in outpatients with SSTIs, but they carried many virulence genes, ST59-SCC ITALIC! mecIV a-PVL-positive clone was the predominant clone in Wuhan, China. PMID:27060098

  3. Nasal carriage of a single clone of community-acquired methicillin-resistant Staphylococcus aureus among kindergarten attendees in northern Taiwan

    Lee Shih-Yi

    2007-06-01

    Full Text Available Abstract Background: To evaluate the prevalence and microbiological characterization of community-acquired (CA methicillin-resistant Staphylococcus aureus (MRSA nasal carriage in a kindergarten. Methods: Point prevalence study. Nasal swabs were collected from healthy children younger than 7 years of age who were attending a kindergarten in Taipei, Taiwan. A parent questionnaire regarding MRSA risk factors was administered simultaneously. All CA-MRSA colonization isolates were archived for subsequent antimicrobial susceptibility and molecular typing. Results: Of the 68 children who participated in the study, 17 (25% had S. aureus isolated from nasal swabs. Nine (13.2% of the 68 children had CA-MRSA carriage, and none of them had any identified risk factors. Antimicrobial susceptibility testing revealed all of the 9 CA-MRSA colonization isolates had uniformly high resistance (100% to both clindamycin and erythromycin, the macrolide-lincosamide-streptogramin-constitutive phenotype and the ermB gene. Pulsed-field gel electrophoresis revealed 8 (88.9% of 9 CA-MRSA colonization isolates were genetically related and multilocus sequence typing revealed all isolates had sequence type 59. All of the colonization isolates carried the staphylococcal cassette chromosome mec type IV, but none were positive for the Panton-Valentine leukocidin genes. Conclusion: The results of this study suggest that a single predominant CA-MRSA colonization strain featuring high clindamycin resistance circulated in this kindergarten. Additionally, due to the established transmissibility of colonization isolates, the high prevalence of nasal carriage of CA-MRSA among healthy attendees in kindergartens may indicate the accelerated spread of CA-MRSA in the community.

  4. Quality control of direct molecular diagnostics for methicillin-resistant Staphylococcus aureus.

    A.F. van Belkum (Alex); H.G.M. Niesters (Bert); W.G. MacKay (William); W.B. van Leeuwen (Willem)

    2007-01-01

    textabstractTen samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Sample

  5. Quality control of direct molecular diagnostics for methicillin-resistant Staphylococcus aureus

    van Belkum, Alex; Niesters, Hubert G M; MacKay, William G; van Leeuwen, Willem B

    2007-01-01

    Ten samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Samples containing

  6. Insights on Evolution of Virulence and Resistance from the Complete Genome Analysis of an Early Methicillin-Resistant Staphylococcus aureus Strain and a Biofilm-Producing Methicillin-Resistant Staphylococcus epidermidis Strain†

    Gill, Steven R.; Derrick E Fouts; Archer, Gordon L.; Mongodin, Emmanuel F.; DeBoy, Robert T; Ravel, Jacques; Paulsen, Ian T.; Kolonay, James F.; Brinkac, Lauren; Beanan, Mauren; Robert J Dodson; Sean C Daugherty; Madupu, Ramana; Angiuoli, Samuel V; Durkin, A. Scott

    2005-01-01

    Staphylococcus aureus is an opportunistic pathogen and the major causative agent of numerous hospital- and community-acquired infections. Staphylococcus epidermidis has emerged as a causative agent of infections often associated with implanted medical devices. We have sequenced the ∼2.8-Mb genome of S. aureus COL, an early methicillin-resistant isolate, and the ∼2.6-Mb genome of S. epidermidis RP62a, a methicillin-resistant biofilm isolate. Comparative analysis of these and other staphylococc...

  7. Susceptibility of methicillin-resistant Staphylococcus aureus to lysostaphin.

    Huber, M M; Huber, T. W.

    1989-01-01

    One hundred and eleven isolates of methicillin-resistant Staphylococcus aureus recovered from patients at the Olin E. Teague Veterans Center from March 1983 to April 1987 were as susceptible to lysis by lysostaphin as methicillin-susceptible S. aureus controls were.

  8. Advances of community-acquired methicillin-resistant Staphylococcus aureus%社区获得性耐甲氧西林金黄色葡萄球菌研究现状

    季剑苹

    2012-01-01

    一直以来,耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)作为医院内感染的重要病原菌,其临床特征及耐药状况一直备受关注.然而自20世纪90年代首次报道社区获得性耐甲氧西林金黄色葡萄球菌(community-acquired methicillin-resistant Staphylococcus aureus,CA-MRSA)后,20年来尤其是近3年来其感染率明显上升,并有超过医院获得性耐甲氧西林金黄色葡萄球菌(hospital-acquired methicillin-resistant Staphylococcus aureus,HA-MRSA)的趋势,成为社区及医院感染的主要致病菌,其临床特征、耐药状况、传播方式和分子生物学特征与HA-MRSA有着较大的差异.%Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major pathogens of the hospital infection.Its clinical features and drug-resisetance situations have always been concerned.But since the late 1990s,another class of MRSA has become a major concern worldwide as an emerging pathogen in the community.This new class of MRSA is called community-acquired MRSA (CA-MRSA).With the rapid development of the infection of CA-MRSA in 20 years,especially in the latest 3 years,CA-MRSA may be replacing the hospital-acquired MRSA strains(HA-MRSA) as one of the major pathogens in the hospital and the community as well.The characteristics of CA-MRSA are very different from those of HA-MRSA.This review summarizes the current studies of CA-MRSA on the epidemiology and the molecular characteristics.

  9. Laboratory Maintenance of Methicillin-Resistant Staphylococcus aureus (MRSA)

    Nicholas P Vitko; Richardson, Anthony R.

    2013-01-01

    Staphylococcus aureus is an important bacterial pathogen in the hospital and community settings, especially Staphylococcus aureus clones that exhibit methicillin-resistance (MRSA). Many strains of S. aureus are utilized in the laboratory, underscoring the genetic differences inherent in clinical isolates. S. aureus grows quickly at 37°C with aeration in rich media (e.g. BHI) and exhibits a preference for glycolytic carbon sources. Furthermore, S. aureus has a gold pigmentation, exhibits β-hem...

  10. PREVALENCE OF HETEROGENEOUS GLYCOPEPTIDE INTERMEDIATE RESISTANCE IN METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS

    Manu Chaudhary; Anurag Payasi

    2013-01-01

    Multidrug resistant Methicillin-Resistant Staphylococcus Aureus (MRSA) is a major cause of nosocomial and community acquired infections and is on the rise. The aim of this investigation was to explore the prevalence of MRSA and heterogeneous Glycopeptide Intermediate Staphylococcus Aureus (hGISA) in various clinical samples, to investigate the various antibiotic resistant determinant genes among these strains collected from north and west Indian hospitals and to evaluate the response of vario...

  11. Methicillin resistant Staphylococcus aureus (MRSA) in the intensive care unit

    Haddadin, A; Fappiano, S; Lipsett, P

    2002-01-01

    Methicillin resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen that causes severe morbidity and mortality worldwide. MRSA strains are endemic in many American and European hospitals and account for 29%–35% of all clinical isolates. Recent studies have documented the increased costs associated with MRSA infection, as well as the importance of colonisation pressure. Surveillance strategies have been proposed especially in high risk areas such as the intensive care unit. Pneum...

  12. Bactericidal antibiotic-phytochemical combinations against methicillin resistant Staphylococcus aureus

    Bhone Myint Kyaw; Shuchi arora; Chu Sing Lim

    2012-01-01

    Methicillin resistant Staphylococcus aureus (MRSA) infection is a global concern nowadays. Due to its multi-drug resistant nature, treatment with conventional antibiotics does not assure desired clinical outcomes. Therefore, there is a need to find new compounds and/or alternative methods to get arsenal against the pathogen. Combination therapies using conventional antibiotics and phytochemicals fulfill both requirements. In this study, the efficacy of different phytochemicals in combination ...

  13. Personal Hygiene and Methicillin-resistant Staphylococcus aureus Infection

    Turabelidze, George; Lin, Mei; Wolkoff, Barbara; Dodson, Douglas; Gladbach, Stephen; Zhu, Bao-Ping

    2006-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections outside the healthcare setting are an increasing concern. We conducted a case-control study to investigate an MRSA outbreak during 2002–2003 in a Missouri prison and focused on hygiene factors. Information on sociodemographic characteristics, medical history, and hygiene practices of study participants was collected by interview and medical record review. Logistic regression was used to evaluate MRSA infection in relation to hygien...

  14. Methicillin-Resistant Staphylococcus aureus Ocular Infection in Taiwan

    Kang, Yu-Chuan; Hsiao, Ching-Hsi; Yeh, Lung-Kun; Ma, David H. K.; Chen, Phil Y. F.; Lin, Hsin-Chiung; Tan, Hsin-Yuan; Chen, Hung-Chi; Chen, Shin-Yi; Huang, Yhu-Chering

    2015-01-01

    Abstract Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important public health issue. This observational study aimed to characterize clinical features, antibiotic susceptibility, and genotypes of ocular infections caused by MRSA based on the clinical and molecular definitions of community-associated (CA) and healthcare-associated (HA) strains. Fifty-nine patients with culture-proven S aureus ocular infection were enrolled from January 1, 2010 to December 31, 2011 at Chang...

  15. [Atypical presentation of diffuse tropical pyomiositis of the psoas due to methicillin resistant Staphylococcus aureus].

    Ticse, Ray; Melgarejo, Weymar; Fuentes-Dávila, Alfredo; Ortíz, Jesús; Zegarra, Jaime

    2012-03-01

    Diffuse tropical primary pyomyositis is an infrequent entity in our country, with few cases associated to community-acquired Methicillin- resistant Staphylococcus aureus. There are no reported cases of Community-Acquired Methicillin- Resistant Staphylococcus aureus (CA- MRSA) in Peru. We present the case of a 70 year old male with a previous diagnosis of type 2 diabetes mellitus, receiving irregular treatment, who was admitted to the hospital with a history of 10 days of low back pain radiating to the left leg, fever and forced flexion of the right hip due to pain during movement. The diagnosis of diffuse pyomyositis of both psoas muscles was performed with MRI and culture of a posterior paravertebral collection, from which Staphylococcus aureus resistant to oxacillin, penicillin and dicloxacillin was isolated. PMID:22510919

  16. Rapid detection (4 h) of methicillin-resistant Staphylococcus aureus by a bioluminescence method.

    Park, C. H.; Hixon, D L; McLaughlin, C M; Cook, J F

    1988-01-01

    A 4-h bioluminescence method for methicillin susceptibility determination was compared with reference methods. Of the Staphylococcus aureus strains tested, 80 were methicillin resistant, 180 were methicillin susceptible, and 10 were borderline susceptible. There was 100% correlation between bioluminescence and reference methods for methicillin-susceptible and methicillin-resistant strains. All borderline-susceptible strains were identified as methicillin resistant by bioluminescence.

  17. Draft Genome Sequences of Staphylococcus aureus AMRF1 (ST22) and AMRF2 (ST672), Ocular Methicillin-Resistant Isolates

    Velusamy, Nithya

    2014-03-20

    Sequence type 22 (ST22) and ST672 are the two major emerging clones of community-acquired methicillin-resistant Staphylococcus aureus in India. ST672 strains were found to cause severe ocular infections. We report the draft genome sequences of two emerging strains of methicillin-resistant S. aureus, AMRF1 (ST22) and AMRF2 (ST672), isolated from patients with ocular infections.

  18. Methicillin-Resistant Staphylococcus aureus (MRSA) Treatment

    ... Laboratory of Bacteriology Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) Antibacterial Resistance Leadership Group (ARLG) NIAID Antimicrobial Resistance Funding Information ...

  19. Methicillin-Resistant Staphylococcus aureus (MRSA) Diagnosis

    ... Laboratory of Bacteriology Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) Antibacterial Resistance Leadership Group (ARLG) NIAID Antimicrobial Resistance Funding Information ...

  20. ST59 Type Community Acquired Methicillin Resistant Staphylococcus aureus Virulence Factors%ST59型社区获得性耐甲氧西林金黄色葡萄球菌毒力因子研究

    陈咏君; 田素飞; 褚云卓; 郭丽洁; 丁丽萍; 李富顺

    2013-01-01

    了解ST59型社区获得性耐甲氧西林金黄色葡萄球菌(community-acquired methicillin-resistant Staphylococcus aureus,CA-MRSA)携带毒力因子的情况.用PCR方法扩增ST59型CA-MRSA PSMα、PVL、SEA、SEB、SEC、SED、SEE、TSST-1、ETA、ETB基因.5株CA-MRSA全部检出PSMα基因和PVL基因,均未检出SEA、SEB、SEC、SED、SEE、TSST-1、ETA、ETB基因.PSMα和PVL基因是ST59型社区获得性耐甲氧西林金黄色葡萄球菌常见的毒力因子.%In order to understand virulence factors carrying case of STS9 type community acquired methicillin resistant S. aureus (CA-MRSA) , PSMα, PVL, SEA, SEB, SEC, SED, SEE, TSST-1, ETA, and ETB genes of ST59 type were amplified by PCR. The results showed that 5 strains of ST59 CA-MRSA were all detected PSMa and PVL genes, however, SEA, SEB, SEC, SED, SEE, TSST-1, ETA, and ETB genes were not detected. Therefore, PSMα and PVL genes were common virulence factors of ST59 type CA-MRSA.

  1. Epidemic Increase in Methicillin-resistant Staphylococcus aureus in Copenhagen

    Westh, Henrik; Boye, Kit; Bartels, Mette Damkjær;

    2006-01-01

    INTRODUCTION: We have found an epidemic increase in methicillin-resistant Staphylococcus aureus (MRSA) in Copenhagen. The increase has a complex background and involves hospitals, nursing homes and persons nursed in their own home. MATERIAL AND METHODS: We found 33 MRSA patients in 2003 and 121 in...... 2004. All isolates have been spa-typed and epidemiologic information collected. RESULTS: The number of MRSA cases has a doubling time of about six months. The epidemic has been caused by many different MRSA types and 31 staphylococcus protein A genotypes (spa types). MRSA has caused several hospital...

  2. Epidemic Increase in Methicillin-resistant Staphylococcus aureus in Copenhagen

    Westh, Henrik; Boye, Kit; Bartels, Mette Damkjær;

    2006-01-01

    INTRODUCTION: We have found an epidemic increase in methicillin-resistant Staphylococcus aureus (MRSA) in Copenhagen. The increase has a complex background and involves hospitals, nursing homes and persons nursed in their own home. MATERIAL AND METHODS: We found 33 MRSA patients in 2003 and 121...... in 2004. All isolates have been spa-typed and epidemiologic information collected. RESULTS: The number of MRSA cases has a doubling time of about six months. The epidemic has been caused by many different MRSA types and 31 staphylococcus protein A genotypes (spa types). MRSA has caused several hospital...

  3. Reduced Triclosan Susceptibility in Methicillin-Resistant Staphylococcus epidermidis

    Schmid, Molly B.; Kaplan, Nachum

    2004-01-01

    Triclosan MIC determination showed that recent Staphylococcus aureus clinical isolates (n = 100) were highly susceptible to triclosan, with a 50% minimal inhibitory concentration (MIC50) of 0.12 μg/ml and a MIC90 of 0.25 μg/ml. Staphylococcus epidermidis isolates (n = 96) were less susceptible, with a MIC50 of 0.12 μg/ml and a MIC90 of 8 μg/ml. Decreased susceptibility to triclosan was more prevalent among methicillin-resistant S. epidermidis than among methicillin-sensitive S. epidermidis is...

  4. Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from Patients with Persistent or Recurrent Bacteremia

    Henry Wong

    2014-01-01

    Full Text Available BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA bloodstream infections (BSI are associated with considerable morbidity and mortality, especially with persistent (PB or recurrent bacteremia (RB.

  5. Methicillin-Resistant Staphylococcus aureus (MRSA) Detected at Four U.S. Wastewater Treatment Plants

    Goldstein, Rachel E. Rosenberg; Shirley A. Micallef; Gibbs, Shawn G.; Davis, Johnnie A.; He, Xin; George, Ashish; Kleinfelter, Lara M.; Schreiber, Nicole A.; Mukherjee, Sampa; Sapkota, Amir; Joseph, Sam W.; Sapkota, Amy R.

    2012-01-01

    Background: The incidence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections is increasing in the United States, and it is possible that municipal wastewater could be a reservoir of this microorganism. To date, no U.S. studies have evaluated the occurrence of MRSA in wastewater. Objective: We examined the occurrence of MRSA and methicillin-susceptible S. aureus (MSSA) at U.S. wastewater treatment plants. Methods: We collected wastewater samples from two Mid...

  6. Development of antimicrobial resistance in acinetobacter spp and methicillin-resistant staphylococcus aureus

    Davies, Sarah Elisabeth

    2009-01-01

    Background: Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus (MRSA) represent the most worrying Gram-negative and Gram-positive nosocomial pathogens of the present age. They are of increasing concern in the clinical environment due to their multi-drug resistance and the dwindling therapeutic options available. A. baumannii is the most frequently isolated clinical species of the genus, and is able to rapidly acquire resistance. Hypermutators, most frequent...

  7. Misidentification of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals in Tripoli, Libya

    Ahmed, Mohamed O; Abdulbaset R. Abuzweda; Alghazali, Mohamed H.; Asma K Elramalli; Amri, Samira G.; Aghila, Ezzeddin Sh.; Abouzeed, Yousef M

    2010-01-01

    Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a nosocomial (hospital-acquired) pathogen of exceptional concern. It is responsible for life-threatening infections in both the hospital and the community. Aims: To determine the frequency of MRSA misidentification in hospitals in Tripoli, Libya using current testing methods. Methods: One hundred and seventy S. aureus isolates previously identified as MRSA were obtained from three hospitals in Tripoli. All isolates were reident...

  8. Clinical utility of the Xpert MRSA assay for early detection of methicillin-resistant Staphylococcus aureus

    OH, AE-CHIN; Lee, Jin Kyung; LEE, HA NA; HONG, YOUNG JUN; Chang, Yoon Hwan; Hong, Seok-Il; Kim, Dong Ho

    2012-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for many nosocomial and community-acquired infections, resulting in significant morbidity and mortality. A practical way to limit the spread of MRSA is early detection and proper treatment. However, screening culture for MRSA typically requires 2–3 days. The Xpert MRSA assay (Cepheid, Sunnyvale, CA, USA) is a real-time polymerase chain reaction-based assay developed for screening an MRSA-specific DNA sequence within the staphyl...

  9. Prospective analysis methicillin-resistant staphylococcus aureus and its risk factors

    Abdallah, Soad A; Khulood K Al-Asfoor; Mona F Salama; Al-Awadi, Bashayer M

    2013-01-01

    Background: Since the early nineties, a new methicillin-resistant Staphylococcus aureus (MRSA) has existed in a form correlating with community health personnel. Community-acquired MRSA (CA-MRSA) could be differentiated from healthcare-associated MRSA (HA-MRSA) microbiologically, epidemiologically, and molecularly. Aims: To determine the prevalence, risk factors of MRSA infections in community and hospital. Settings: The incidence and risk factors for CA-MRSA and HA-MRSA among patients of med...

  10. Prospective Analysis Methicillin-resistant Staphylococcus aureus and its Risk Factors

    Abdallah, Soad A; Khulood K Al-Asfoor; Mona F Salama; Al-Awadi, Bashayer M

    2013-01-01

    Background: Since the early nineties, a new methicillin-resistant Staphylococcus aureus (MRSA) has existed in a form correlating with community health personnel. Community-acquired MRSA (CA-MRSA) could be differentiated from healthcare-associated MRSA (HA-MRSA) microbiologically, epidemiologically, and molecularly. Aims: To determine the prevalence, risk factors of MRSA infections in community and hospital. Settings: The incidence and risk factors for CA-MRSA and HA-MRSA among patients of med...

  11. Methicillin-resistant Staphylococcus lugdunensis carrying SCCmec type V misidentified as MRSA

    Eliezer Menezes Pereira

    2011-06-01

    Full Text Available Staphylococcus lugdunensis is a rare cause of severe infections and clinical manifestations are similar to those related to S. aureus infection. We describe a hospital-acquired bacteremia due to methicillin-resistant Staphylococcus lugdunensis, misidentified as methicillin-resistant S. aureus. The oxacillin MIC was 16 µg/mL and the mecA gene and SCCmec type V were determined by PCR. Although treatment had been appropriated, the patient died after rapid progressive respiratory failure and another nosocomial sepsis. It is important not only to identify S. lugdunensis in view of its clinical course, but also to determine its susceptibility to oxacillin by detecting the mecA gene or its product.

  12. Methicillin-Resistant Staphylococcus aureus Colonization in Schoolteachers in Ontario

    Beth A Hanselman

    2008-01-01

    Full Text Available A prospective study of methicillin-resistant Staphylococcus aureus (MRSA colonization was performed involving teachers at a science teachers’ conference in Toronto, Ontario. Nasal swabs and questionnaire data were collected from consenting individuals. MRSA colonization was identified in seven of 220 (3.2% participants. No colonized individuals reported recent contact with the health care system, antimicrobial therapy, residence with health care workers or previous MRSA infections. Methicillin-susceptible S aureus colonization was identified in 72 of 220 (33% individuals. The prevalence of MRSA colonization was higher than expected for a purportedly low-risk population.

  13. Methicillin-resistant Staphylococcus aureus colonization in schoolteachers in Ontario.

    Hanselman, Beth A; Kruth, Steven A; Rousseau, Joyce; Weese, J Scott

    2008-11-01

    A prospective study of methicillin-resistant Staphylococcus aureus (MRSA) colonization was performed involving teachers at a science teachers' conference in Toronto, Ontario. Nasal swabs and questionnaire data were collected from consenting individuals. MRSA colonization was identified in seven of 220 (3.2%) participants. No colonized individuals reported recent contact with the health care system, antimicrobial therapy, residence with health care workers or previous MRSA infections. Methicillin-susceptible S aureus colonization was identified in 72 of 220 (33%) individuals. The prevalence of MRSA colonization was higher than expected for a purportedly low-risk population. PMID:19436569

  14. Inhibition of methicillin resistant Staphylococcus aureus by a plasma needle

    Miletić, Maja; Vuković, Dragana; Živanović, Irena; Dakić, Ivana; Soldatović, Ivan; Maletić, Dejan; Lazović, Saša; Malović, Gordana; Petrović, Zoran; Puač, Nevena

    2014-03-01

    In numerous recent papers plasma chemistry of non equilibrium plasma sources operating at atmospheric pressure has been linked to plasma medical effects including sterilization. In this paper we present a study of the effectiveness of an atmospheric pressure plasma source, known as plasma needle, in inhibition of the growth of biofilm produced by methicillin resistant Staphylococcus aureus (MRSA). Even at the lowest powers the biofilms formed by inoculi of MRSA of 104 and 105 CFU have been strongly affected by plasma and growth in biofilms was inhibited. The eradication of the already formed biofilm was not achieved and it is required to go to more effective sources.

  15. Treatment of methicillin-resistant Staphylococcus aureus: vancomycin and beyond.

    Holmes, Natasha E; Tong, Steven Y C; Davis, Joshua S; van Hal, Sebastiaan J

    2015-02-01

    There has been a welcome increase in the number of agents available for the treatment of methicillin-resistant Staphylococcus aureus (MRSA). Vancomycin remains an acceptable treatment option, with moves toward individualized dosing to a pharmacokinetic/pharmacodynamic (PK/PD) target. Numerous practicalities, however, would need to be resolved before implementation. Lipoglycopeptides as a class show excellent in vitro potency. Their long half-lives and complex PKs may preclude these agents being used in critically ill patients. Anti-MRSA cephalosporins provide great promise in the treatment of MRSA. These agents, despite broad-spectrum activity, should be reserved for patients with MRSA infections as it is likely that usage will be associated with increased rates of resistance. Daptomycin is currently the only antibiotic to have shown noninferiority to vancomycin in the treatment of MRSA bacteremia. The results of an open-labeled trial to address the superiority of daptomycin compared with vancomycin in reduced vancomycin susceptibility infections are eagerly anticipated. No drug to date has shown superiority to vancomycin in the treatment of MRSA infections with the possible exception of linezolid in hospital-acquired pneumonia (HAP), making linezolid an important option in the treatment of MRSA-proven HAP. Whether these strengths and features are agent or class specific are unclear but will likely be answered with the marketing of tedizolid. There are insufficient data to recommend either quinupristin/dalfopristin or tigecycline, as first line in the treatment of severe MRSA infections. These agents however remain options in patients with no other alternatives. PMID:25643268

  16. Methicillin-Resistant Staphylococcus aureus Colonization among Health Care Workers in a Downtown Emergency Department in Toronto, Ontario

    Gregory Saito

    2013-01-01

    Full Text Available BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA acquired in the community, otherwise known as community-acquired MRSA, has emerged rapidly in recent years. Colonization with MRSA has been associated with an increased risk of symptomatic and serious infections and, in some settings, health care workers (HCWs exhibit a higher prevalence of MRSA colonization.

  17. Nasal carriage of Methicillin-resistant Staphylococcus aureus among healthy population of Kashmir, India

    B A Fomda

    2014-01-01

    Full Text Available Background: Nasal colonisation with community acquired methicillin resistant Staphylococcus aureus (CA-MRSA is being increasingly reported, especially in places where people are in close contact and where hygiene is compromised. The aim of this study was to find out prevalence of methicillin resistant S.aureus (MRSA colonising anterior nares of healthy subjects. Materials and Methods: Nasal swabs of healthy subjects were collected aseptically and cultured using standard microbiological protocols. Antibiotic susceptibility was done by Kirby-Bauer disc diffusion method according to CLSI guidelines. Methicillin resistance was detected by cefoxitin disc diffusion method and confirmed by minimum inhibitory concentration (MIC and amplification of mecA gene by PCR. Strain typing of MRSA strains was done by PFGE. Results: Out of 820 samples, S.aureus was isolated from 229 (27.92% subjects. Of the 229 isolates, 15 were methicillin resistant. All S. aureus isolates were susceptible to vancomycin. Nasal carriage of MRSA was found to be 1.83% among healthy population. The isolates were found to be polyclonal by PFGE analysis. Conclusion: High prevalence of MRSA is a cause of concern and strategies to interrupt transmission should be implemented.

  18. The dominant Australian community-acquired methicillin-resistant Staphylococcus aureus clone ST93-IV [2B] is highly virulent and genetically distinct.

    Kyra Y L Chua

    Full Text Available Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA USA300 has spread rapidly across North America, and CA-MRSA is also increasing in Australia. However, the dominant Australian CA-MRSA strain, ST93-IV [2B] appears distantly related to USA300 despite strikingly similar clinical and epidemiological profiles. Here, we compared the virulence of a recent Australian ST93 isolate (JKD6159 to other MRSA, including USA300, and found that JKD6159 was the most virulent in a mouse skin infection model. We fully sequenced the genome of JKD6159 and confirmed that JKD6159 is a distinct clone with 7616 single nucleotide polymorphisms (SNPs distinguishing this strain from all other S. aureus genomes. Despite its high virulence there were surprisingly few virulence determinants. However, genes encoding α-hemolysin, Panton-Valentine leukocidin (PVL and α-type phenol soluble modulins were present. Genome comparisons revealed 32 additional CDS in JKD6159 but none appeared to encode new virulence factors, suggesting that this clone's enhanced pathogenicity could lie within subtler genome changes, such as SNPs within regulatory genes. To investigate the role of accessory genome elements in CA-MRSA epidemiology, we next sequenced three additional Australian non-ST93 CA-MRSA strains and compared them with JKD6159, 19 completed S. aureus genomes and 59 additional S. aureus genomes for which unassembled genome sequence data was publicly available (82 genomes in total. These comparisons showed that despite its distinctive genotype, JKD6159 and other CA-MRSA clones (including USA300 share a conserved repertoire of three notable accessory elements (SSCmecIV, PVL prophage, and pMW2. This study demonstrates that the genetically distinct ST93 CA-MRSA from Australia is highly virulent. Our comparisons of geographically and genetically diverse CA-MRSA genomes suggest that apparent convergent evolution in CA-MRSA may be better explained by the rapid

  19. Proti meticilinu odporna bakterija Staphylococcus aureus domačega okolja (CA-MRSA): Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA):

    Dermota, Urška; Grmek-Košnik, Irena; Juteršek, Borut

    2005-01-01

    Background. Community acquired MRSA (CA-MRSA) infections affect patients without risk factors. CA-MRSA infections can be serious and also fatal even inpreviously healthy subjects. CA-MRSA differs from hospital acquired MRSA (HA-MRSA). CA-MRSA is more susceptible for non-beta-lactam antibiotics than HA-MRSA, has different PFGE subtypes, and can produce Panton-Valentine leukocidine. Methods. In Institute of Public Health Kranj we routinely performepidemiologic survey of MRSA positive patients. ...

  20. Enfermedad invasora por Staphylococcus aureus meticilino resistente adquirida en la comunidad Community-acquired methicillin-resistant Staphylococcus aureus disseminated disease

    Clarisa Brezzo

    2006-10-01

    Full Text Available Se presenta un caso de enfermedad invasora por Staphylococcus aureus meticilino resistente (SAMR adquirido en la comunidad (SAMR-c. Paciente varón de 21 años, previamente sano, que consultó por nódulos subcutáneos compatibles con gomas. La ultrasonografía reveló múltiples abscesos subcutáneos e imágenes consistentes con piomiositis, además de derrame pleural y pericárdico. En el cultivo del material purulento obtenido por punción-aspiración con aguja fina de las lesiones se aisló S. aureus. El antibiograma por difusión mostró resistencia a cefalotina, eritromicina y clindamicina, y sensibilidad a trimetroprima-sulfametoxazol, ciprofloxacina y rifampicina. La meticilino resistencia se confirmó por aglutinación con partículas de látex sensibilizadas con anticuerpos monoclonales dirigidos contra la proteína ligadora de penicilina 2A. El paciente fue tratado con ciprofloxacina y rifampicina durante cuatro semanas, con evolución favorable. La frecuencia de infecciones por SAMR-c está en aumento, observándose en personas sin factores de riesgo aparentes. Esto llevaría a fracaso en el tratamiento empírico para infecciones de la comunidad en los que se presume etiología estafilocócica.A 21 year old man, previously healthy, presented with subcutaneous nodes consistent with gummas. Ultrasonography disclosed multiple subcutaneous abscesses and images suitable with piomiositis, pleural and pericardium effusion. A puncture-aspirate with fine-needle was performed and produced purulent material, with isolate of Staphylococcus aureus. Antimicrobial susceptibility testing by disk diffusion showed resistant to cefalotin, erythromycin and clindamycin, and susceptibility to trimethoprim-sulfamethoxazole, ciprofloxacin and rifampicin. Methicilin-resistance was confirmed by Staphyslide agglutination testing (Biomérieux. The patient was treated with ciprofloxacin and rifampicin during four weeks, with a good clinical response. The

  1. Hospital-acquired infection with methicillin-resistant and methicillin-sensitive staphylococci.

    Law, M R; Gill, O. N.

    1988-01-01

    In-patients at a London hospital over one year from whom the south-east England strain of 'epidemic' methicillin-resistant Staphylococcus aureus (MRSA) was isolated were compared with in-patients with strains of methicillin-sensitive Staphylococcus aureus (MSSA). MRSA were virtually entirely hospital-acquired; isolates before 10 days were uncommon and related to recent previous admission. Thereafter first isolates occurred at a fairly constant daily rate of about 1.9 per 1,000 in-patients. Ac...

  2. Reversal of methicillin resistance in Staphylococcus aureus by thioridazine

    Klitgaard, Janne K; Skov, Marianne N; Kallipolitis, Birgitte H;

    2008-01-01

    Objectives Thioridazine has been shown to reverse oxacillin resistance in methicillin-resistant Staphylococcus aureus (MRSA) in vitro. The aim of this study was to investigate whether thioridazine alone or in combination with oxacillin affects the transcription of the methicillin resistance gene...... that reversal of methicillin resistance by thioridazine in MRSA may be explained by a reduced transcription of mecA and blaZ, resulting in a reduced protein level of PBP2a....

  3. Frequency of methicillin-resistant Staphylococcus aureus nasal colonization among patients suffering from methicillin resistant Staphylococcus aureus bacteraemia

    Aslam, Nadia; Izhar, Mateen; Mehdi, Naima

    2013-01-01

    Objective: To determine rate of nasal colonization in Patients suffering from bacteraemia caused by methicillin resistant Staphylococcus aureus. Methods: This descriptive cross sectional study was carried out in a tertiary ca re, University Teaching Hospital (Shaikh Zayed Hospital, Lahore) from October 2010 to August 2011. Nasal swabs were taken from patients suffering from MRSA bacteraemia and were plated on mannitol salt agar plates to isolate Staphylococcus aureus (S. aureus) which were then tested for oxacillin susceptibility. Results: Nasal colonization was present in 52.5% of patients suffering from MRSA bacteraemia. Conclusion: Nasal colonization rates with MRSA were high among patients suffering from MRSA bacteraemia especially in those undergoing dialysis or surgical procedures. Therefore, screening and nasal decolonization should be practiced in hospitals. PMID:24550968

  4. Comparative Efficacy of Ceftaroline with Linezolid against Staphylococcus Aureus and Methicillin Resistant Staphylococcus Aureus

    Objective:To compare the in vitro antimicrobial efficacy of ceftaroline with linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. Study Design: Quasi-experimental study. Place and Duration of Study: Microbiology Department, Army Medical College, Rawalpindi, from January to December 2013. Methodology: Clinical samples from respiratory tract, blood, pus and various catheter tips routinely received in the Department of Microbiology, Army Medical College, Rawalpindi were innoculated on blood and MacConkey agar. Staphylococcus aureus was identified by colony morphology, Gram reaction, catalase test and coagulase test. Methicillin resistant Staphylococcus aureus detection was done by modified Kirby Bauer disc diffusion method using cefoxitin disc (30g) and the isolates were considered methicillin resistant if the zone of inhibition around cefoxitin disc was /sup 2/ 21 mm. Bacterial suspensions of 56 Staphylococcus aureus isolates and 50 MRSA isolates were prepared, which were standardized equal to 0.5 McFarland's turbidity standard and inoculated on Mueller-Hinton agar plates followed by application of ceftaroline and linezolid disc (Oxoid, UK), according to manufacturer's instructions. The plates were then incubated at 37 Degree C aerobically for 18 - 24 hours. Diameters of inhibition zone were measured and interpretated as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Out of 106 isolates all of the 56 Staphylococcus aureus (100%) were sensitive to ceftaroline and linezolid. However, out of 50 methicillin resistant Staphylococcus aureus, 48 (96%) were sensitive to ceftaroline whereas, 49 (98%) were sensitive to linezolid. Conclusion: Ceftaroline is equally effective as linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. (author)

  5. Missense mutations in PBP2A Affecting ceftaroline susceptibility detected in epidemic hospital-acquired methicillin-resistant Staphylococcus aureus clonotypes ST228 and ST247 in Western Switzerland archived since 1998

    Kelley, William; Jousselin, Ambre; Barras, Christine; Lelong, Emmanuelle; Renzoni, Adriana Maria

    2015-01-01

    The development and maintenance of an arsenal of antibiotics is a major health care challenge. Ceftaroline is a new cephalosporin with activity against methicillin-resistant Staphylococcus aureus (MRSA); however, no reports concerning MRSA ceftaroline susceptibility have been reported in Switzerland. We tested the in vitro activity of ceftaroline against an archived set of 60 MRSA strains from the University Hospital of Geneva collected from 1994 to 2003. Our results surprisingly revealed cef...

  6. Community Acquisition of Gentamicin-Sensitive Methicillin-Resistant Staphylococcus aureus in Southeast Queensland, Australia

    Nimmo, Graeme R.; Schooneveldt, Jacqueline; O'Kane, Gabrielle; McCall, Brad; Vickery, Alison

    2000-01-01

    Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) susceptible to gentamicin has been reported in a number of countries in the 1990s. To study the acquisition of gentamicin-sensitive MRSA (GS-MRSA) in southeast Queensland and the relatedness of GS-MRSA to other strains of MRSA, 35 cases of infection due to GS-MRSA from October 1997 through September 1998 were examined retrospectively to determine the mode of acquisition and risk factors for MRSA acquisition. Thirty-one isol...

  7. Prevalence of methicillin-resistant Staphylococcus aureus in poultry meat in Qena, Egypt

    Mohamed Karmi

    2013-01-01

    Aim: To study the prevalence of pathogenic coagulase positive, methicillin-resistant Staphylococcus aureus (MRSA) in poultry meat and its products. Materials and Methods: A total of 125 poultry samples were collected during 2012 in Qena governorate for presence of pathogenic coagulase positive, methicillin-resistant staphylococcus aureus (MRSA). Samples were taken from freshly slaughtered whole chicken carcasses (25/125), chicken portions (25/125), chicken luncheon (25/125), chicken sausages ...

  8. Methicillin-Resistant Staphylococcus aureus in the Neonatal Intensive Care Unit

    Nelson, Melissa U.; Gallagher, Patrick G.

    2012-01-01

    Methicillin-resistant Staphylococcus aureus is a frequent source of infections affecting premature and critically ill infants in neonatal intensive care units. Neonates are particularly vulnerable to colonization and infection with Methicillin-resistant Staphylococcus aureus, and many studies have attempted to identify risk factors that predispose certain infants to its acquisition in order to discover potential areas for clinical intervention. In addition, epidemiologic assessment of transmi...

  9. Ciprofloxacin-resistant methicillin-resistant Staphylococcus aureus in an acute-care hospital.

    Raviglione, M. C.; Boyle, J. F.; Mariuz, P; Pablos-Mendez, A; Cortes, H; Merlo, A.

    1990-01-01

    Use of ciprofloxacin as an alternative to vancomycin for treatment of methicillin-resistant Staphylococcus aureus infection has been paralleled by the emergence of resistant strains. This phenomenon has also been noticed in our hospital. To confirm our observation, methicillin and ciprofloxacin susceptibilities were tested by disk diffusion and broth microdilution techniques. We studied 83 methicillin-resistant Staphylococcus aureus isolates obtained from various sources over a 4-month period...

  10. Emergence of Panton-Valentine leucocidin-positive ST8-methicillin-resistant Staphylococcus aureus (USA300 clone) in Korea causing healthcare-associated and hospital-acquired bacteraemia.

    Jung, J; Song, E H; Park, S Y; Lee, S-R; Park, S-J; Sung, H; Kim, M-N; Kim, S-H; Lee, S-O; Choi, S-H; Woo, J H; Kim, Y S; Chong, Y P

    2016-08-01

    Panton-Valentine leucocidin (PVL)-positive sequence type (ST)8-MRSA-SCCmec IVa (USA300) is the epidemic strain of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in North America. USA300 is extremely rare in South Korea, and PVL-negative ST72 SCCmec type IVc is the predominant CA-MRSA clone. In a multicentre, prospective cohort study of S. aureus bacteraemia, we identified PVL-positive ST8-MRSA isolates by performing multilocus sequence typing and PCR for PVL. We analyzed the clinical characteristics of patients with PVL-positive ST8-MRSA bacteraemia, and performed SCCmec, spa, and agr typing, PCR for arginine catabolic mobile element (ACME), virulence gene profiling, and pulsed-field gel electrophoresis (PFGE). Among a total of 818 MRSA isolates, we identified ten isolates of PVL-positive ST8-MRSA (USA300) (3 from Hospital D, 4 from Hospital G, and 3 from Hospital A), all of which involved exclusively healthcare-associated (5 isolates) and hospital-acquired bacteraemia (5 isolates). This strain accounted for 8~10 % of the hospital-acquired MRSA bacteraemia in Hospitals D and G. Bacteraemia of unknown origin was the most common type of infection followed by pneumonia. All the isolates were SCCmec type IVa, spa type t008, and agr group I. Eight of the isolates harboured ACME. In a PFGE analysis, four isolates were identical to the USA300 control strain, five differed by a single band, and the remaining one differed by two bands. All the isolates were pulsed-field type USA300. This is the first report of healthcare-associated and hospital-acquired bacteraemia caused by USA300 in South Korea. USA300 seems to be an emerging hospital clone in this country. PMID:27209287

  11. Methicillin-Resistant Staphylococcus aureus Colonization among Health Care Workers in a Downtown Emergency Department in Toronto, Ontario

    Gregory Saito; Jessica Thom; Yanliang Wei; Piraveina Gnanasuntharam; Pirasanya Gnanasuntharam; Nathan Kreiswirth; Barbara Willey; Michelle Loftus; Catherine Varner; Vanessa Porter; Allison McGeer; Bjug Borgundvaag

    2013-01-01

    BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) acquired in the community, otherwise known as community-acquired MRSA, has emerged rapidly in recent years. Colonization with MRSA has been associated with an increased risk of symptomatic and serious infections and, in some settings, health care workers (HCWs) exhibit a higher prevalence of MRSA colonization.OBJECTIVE: To determine MRSA colonization in emergency department (ED) HCWs in the setting of a moderate prevalence of MRSA...

  12. Sepse por Staphylococus aureus resistente à meticilina adquirida na comunidade no sul do Brasil Sepsis due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil

    Luciane Cristina Gelatti; Tereza Sukiennik; Ana Paula Becker; Fernanda Matsiko Inoue; Mirian Silva do Carmo; Fernanda Marques da Silva Castrucci; Antônio Carlos Campos Pignatari; Luis Carlos Ribeiro; Renan Rangel Bonamigo; Pedro Alves d?Azevedo

    2009-01-01

    Staphylococcus aureus resistente à meticilina foi inicialmente descrito como um típico microrganismo adquirido em infecções nosocomiais. No entanto, nos últimos anos Staphylococcus aureus resistente à meticilina adquirido na comunidade é causa de infecções de pele e tecidos moles, mas infecções graves como pneumonia e sepse podem ocorrer. Este relato descreve um caso de sepse em criança, complicado com pneumonia secundária a lesão em partes moles por Staphylococcus aureus resistente à meticil...

  13. Methicillin-resistant Staphylococcus aureus in central Iowa wildlife.

    Wardyn, Shylo E; Kauffman, Lin K; Smith, Tara C

    2012-10-01

    Livestock and pets have been identified as carriers of Staphylococcus aureus; however, the role of wild animals as a reservoir of S. aureus strains has not yet been examined. We conducted a pilot study to determine the prevalence of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) in 37 species of wild animals rehabilitated at a university clinic. Nasal, wing, wound, and cloacal swabs were collected. Of 114 animals, seven (6.1%) were MSSA-positive and three (2.6%) were MRSA-positive. The MRSA isolates were obtained from two eastern cottontail rabbits (Sylvilagus floridanus) and a Lesser Yellowlegs (Tringa flavipes), a migratory shorebird. Antibiotic resistance testing of the MRSA isolates revealed that two were additionally resistant to tetracycline and erythromycin, and the third isolate was also resistant to erythromycin, clindamycin, and levofloxacin. All three isolates were positive for the Panton-Valentine leukocidin (PVL) gene. Sequence typing of the staphylococcal protein A (spa) region revealed one MRSA isolate to be t002, whereas the other two MRSA isolates were found to be t008. Our results suggest that S. aureus, including MRSA, is being carried by wild animals, although at a low prevalence with the limited number of animals tested. Additional studies are needed to determine how this may impact human health. PMID:23060511

  14. Typing of Methicillin resistant Staphylococcus aureus: A technical review

    P L Mehndiratta

    2012-01-01

    Full Text Available Increasing prevalence of Methicillin-resistant Staphylococcus aureus (MRSA worldwide is a growing public health concern. MRSA typing is an essential component of an effective surveillance system to describe epidemiological trends and infection control strategies. Current challenges for MRSA typing are focused on selecting the most appropriate technique in terms of efficiency, reliability, ease of performance and cost involved. This review summarises the available information on application, potential and problems of various typing techniques in discriminating the strains and understanding the epidemiology of MRSA strains. The phenotypic methods in general are easier to perform, easier to interpret, cost effective and are widely available, however less discriminatory. The genotypic methods are expensive and technically demanding, however more discriminatory. Newer technologies involving sequencing of various genes are coming up as broadly applicable and high throughput typing systems. Still there is no consensus regarding the single best method for typing of MRSA strains. Phage typing is recommended as first line approach in epidemiological investigation of MRSA strains. PFGE remains the gold standard for characterisation of outbreak strains. DNA sequencing methods including MLST, spa typing, SCCmec typing and toxin gene profile typing are more practical methods for detecting evolutionary changes and transmission events. The choice of typing technique further depends on the purpose of the study, the facilities available and the utility of data generated to answer a desirable research question. A need for harmonisation of typing techniques by following standard protocols is emphasised to establish surveillance networks and facilitate global MRSA control.

  15. Methicillin-resistant Staphylococcus aureus colonization in veterinary personnel.

    Hanselman, Beth A; Kruth, Steve A; Rousseau, Joyce; Low, Donald E; Willey, Barbara M; McGeer, Allison; Weese, J Scott

    2006-12-01

    Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from nares of 27/417 (6.5%) attendees at an international veterinary conference: 23/345 (7.0%) veterinarians, 4/34 (12.0%) technicians, and 0/38 others. Colonization was more common for large-animal (15/96, 15.6%) than small-animal personnel (12/271, 4.4%) or those with no animal patient contact (0/50) (p<0.001). Large-animal practice was the only variable significantly associated with colonization (odds ratio 2.9; 95% confidence interval 1.2-6.6). Pulsed-field gel electrophoresis identified 2 predominant clones with similar distribution among veterinarians as previously reported for horses and companion animals. Canadian epidemic MRSA-2 (CMRSA) was isolated from 11 small-animal and 2 large-animal personnel from the United States (n = 12) and Germany (n = 1). In contrast, CMRSA-5 was isolated exclusively from large-animal personnel (p<0.001) in the United States (n = 10), United Kingdom (n = 2), and Denmark (n = 1). MRSA colonization may be an occupational risk for veterinary professionals. PMID:17326947

  16. Impact of Colonization Pressure and Strain Type on Methicillin-Resistant Staphylococcus aureus Transmission in Children

    Popoola, Victor O; Carroll, Karen C.; Ross, Tracy; Reich, Nicholas G.; Perl, Trish M.; Aaron M Milstone

    2013-01-01

    We studied the transmissibility of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) and healthcare-associated methicillin-resistant S. aureus (HA-MRSA) strains and the association of MRSA colonization pressure and MRSA transmission in critically ill children. Importantly, we found that in hospitalized children MRSA colonization pressure above 10% increases the risk of MRSA transmission 3-fold, and CA-MRSA and HA-MRSA strains have similar transmission dynamics.

  17. Prevention and control of methicillin-resistant Staphylococcus aureus.

    Humphreys, H

    2009-02-01

    Recent efforts to combat infections have focused on pharmaceutical interventions. However, the global spread of antimicrobial resistance calls for the reappraisal of personal and institutional hygiene. Hygiene embodies behavioural and procedural rules that prevent bacterial transmission. Consequently, the chance of spreading bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) is significantly reduced. Hygiene is part of the primacy and totality of patient care, ensuring that no harm is done. Any prevention and control strategy must be underpinned by changes in attitude, embraced by all. The major components of preventing and controlling MRSA include hand and environmental hygiene (as part of standard precautions), patient isolation, and patient\\/staff decolonization. Improving hand hygiene practice is especially important where the risk of infection is highest, e.g. in intensive care. Physical isolation has two advantages: the physical barrier interrupts transmission, and this barrier emphasizes that precautions are required. With limited isolation facilities, risk assessment should be conducted to indicate which patients should be isolated. Environmental hygiene, although important, has a lower priority than standard precautions. When a patient is ready for discharge (home) or transfer (to another healthcare facility), the overall interests of the patient should take priority. All patients should be informed of their MRSA-positive status as soon as possible. Because of increased mupirocin resistance, a selective approach to decolonization should be taken. When MRSA-positive staff are identified, restricting their professional activity will depend on the nature of their work. Finally, politicians and others need to commit to providing the necessary resources to maximize MRSA prevention and control.

  18. Healthcare-Associated Methicillin-Resistant Staphylococcus aureus

    Kumari, Jyoti; Shenoy, Shalini M.; Baliga, Shrikala; Chakrapani, M.; Bhat, Gopalkrishna K.

    2016-01-01

    Objectives: Healthcare-associated methicillin-resistant Staphylococcus aureus (MRSA) is a common pathogen worldwide and its multidrug resistance is a major concern. This study aimed to determine the clinical characteristics and antibiotic susceptibility profile of healthcare-associated MRSA with emphasis on resistance to macrolide-lincosamide-streptogramin B (MLSB) phenotypes and vancomycin. Methods: This cross-sectional study was carried out between February 2014 and February 2015 across four tertiary care hospitals in Mangalore, South India. Healthcare-associated infections among 291 inpatients at these hospitals were identified according to the Centers for Disease Control and Prevention guidelines. Clinical specimens were collected based on infection type. S. aureus and MRSA isolates were identified and antibiotic susceptibility tests performed using the Kirby-Bauer disk diffusion method. The minimum inhibitory concentration of vancomycin was determined using the Agar dilution method and inducible clindamycin resistance was detected with a double-disk diffusion test (D-test). Results: Out of 291 healthcare-associated S. aureus cases, 88 were MRSA (30.2%). Of these, 54.6% were skin and soft tissue infections. All of the isolates were susceptible to teicoplanin and linezolid. Four MRSA isolates exhibited intermediate resistance to vancomycin (4.6%). Of the MRSA strains, 10 (11.4%) were constitutive MLSB phenotypes, 31 (35.2%) were inducible MLSB phenotypes and 14 (15.9%) were macrolide-streptogramin B phenotypes. Conclusion: Healthcare-associated MRSA multidrug resistance was alarmingly high. In routine antibiotic susceptibility testing, a D-test should always be performed if an isolate is resistant to erythromycin but susceptible to clindamycin. Determination of the minimum inhibitory concentration of vancomycin is necessary when treating patients with MRSA infections. PMID:27226908

  19. Bactericidal antibiotic-phytochemical combinations against methicillin resistant Staphylococcus aureus

    Bhone Myint Kyaw

    2012-09-01

    Full Text Available Methicillin resistant Staphylococcus aureus (MRSA infection is a global concern nowadays. Due to its multi-drug resistant nature, treatment with conventional antibiotics does not assure desired clinical outcomes. Therefore, there is a need to find new compounds and/or alternative methods to get arsenal against the pathogen. Combination therapies using conventional antibiotics and phytochemicals fulfill both requirements. In this study, the efficacy of different phytochemicals in combination with selected antibiotics was tested against 12 strains of S. aureus (ATCC MRSA 43300, ATCC methicillin sensitive S. aureus or MSSA 29213 and 10 MRSA clinical strains collected from National University Hospital, Singapore. Out of the six phytochemicals used, tannic acid was synergistic with fusidic acid, minocycline, cefotaxime and rifampicin against most of strains tested and additive with ofloxacin and vancomycin. Quercetin showed synergism with minocycline, fusidic acid and rifampicin against most of the strains. Gallic acid ethyl ester showed additivity against all strains in combination with all antibiotics under investigation except with vancomycin where it showed indifference effect. Eugenol, menthone and caffeic acid showed indifference results against all strains in combination with all antibiotics. Interestingly, no antagonism was observed within these interactions. Based on the fractional inhibitory concentration indices, synergistic pairs were further examined by time-kill assays to confirm the accuracy and killing rate of the combinations over time. The two methods concurred with each other with 92% accuracy and the combinatory pairs were effective throughout the 24 hours of assay. The study suggests a possible incorporation of effective phytochemicals in combination therapies for MRSA infections.

  20. Status Report from the Scientific Panel on Antibiotic Use in Dermatology of the American Acne and Rosacea Society: Part 3: Current Perspectives on Skin and Soft Tissue Infections with Emphasis on Methicillin-resistant Staphylococcus aureus, Commonly Encountered Scenarios when Antibiotic Use May Not Be Needed, and Concluding Remarks on Rational Use of Antibiotics in Dermatology.

    Del Rosso, James Q; Rosen, Ted; Thiboutot, Diane; Webster, Guy F; Gallo, Richard L; Leyden, James J; Walker, Clay; Zhanel, George; Eichenfield, Lawrence

    2016-06-01

    In this third article of the three-part series, management of skin and soft tissue infections is reviewed with emphasis on new information on methicillin-resistant Staphylococcus aureus. Due to changes in the evolution of methicillin-resistant Staphylococcus aureus clones, previous distinctions between healthcare-acquired methicillin-resistant Staphylococcus aureus and community-acquired methicillin-resistant Staphylococcus aureus are currently much less clinically relevant. Many nosocomial cases of methicillin-resistant Staphylococcus aureus infection are now caused by community-acquired methicillin-resistant Staphylococcus aureus, with changing patterns of antibiotic susceptibility and resistance. Also reviewed are clinical scenarios where antibiotics may not be needed and suggestions for optimal use of antibiotic therapy for dermatologie conditions, including recommendations on perioperative antibiotic use. PMID:27386047

  1. Community-acquired necrotizing pneumonia caused by methicillin-resistant Staphylococcus aureus producing Panton–Valentine leukocidin in a Chinese teenager: case report and literature review

    Jie Chen

    2014-09-01

    Conclusions: To our knowledge, this is the first report from Mainland China of necrotizing pneumonia due to PVL-positive CA-MRSA among those aged older than 1 year. CA-MRSA necrotizing pneumonia should be considered in the differential diagnosis of severe community-acquired pneumonia, particularly in previously healthy individuals.

  2. Methicillin-resistant Staphylococcus sp. colonizing health care workers of a cancer hospital

    Dayane de Melo Costa

    2014-09-01

    Full Text Available The aim of the study was to analyze epidemiological and microbiological aspects of oral colonization by methicillin-resistant Staphylococcus of health care workers in a cancer hospital. Interview and saliva sampling were performed with 149 health care workers. Antimicrobial resistance was determined by disk diffusion and minimum inhibitory concentration. Polymerase Chain Reaction, Internal Transcribed Spacer-Polymerase Chain Reaction and Pulsed Field Gel Electrophoresis were performed for genotypic characterization of methicillin-resistant Staphylococcus. Risk factors were determined by logistic regression. Methicillin-resistant Staphylococcus colonization prevalence was 19.5%, denture wearing (p = 0.03, habit of nail biting (p = 0.04 and preparation and administration of antimicrobial (p = 0.04 were risk factors identified. All methicillin-resistant Staphylococcus were S. epidermidis, 94.4% of them had mecA gene. Closely related and indistinguishable methicillin-resistant S. epidermidis were detected. These results highlight that HCWs which have contact with patient at high risk for developing infections were identified as colonized by MRSE in the oral cavity, reinforcing this cavity as a reservoir of these bacteria and the risk to themselves and patients safety, because these microorganisms may be spread by coughing and talking.

  3. Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) at ambient freshwater beaches

    Fogarty, Lisa R.; Haack, Sheridan K.; Johnson, Heather E.; Brennan, Angela K.; Isaacs, Natasha M.; Spencer, Chelsea

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) are a threat to human health worldwide, and although detected at marine beaches, they have been largely unstudied at freshwater beaches. Genes indicating S. aureus (SA; femA) and methicillin resistance (mecA) were detected at 11 and 12 of 13 US Great Lakes beaches and in 18% or 27% of 287 recreational water samples, respectively. Eight beaches had mecA + femA (potential MRSA) detections. During an intensive study, higher bather numbers, staphylococci concentrations, and femA detections were found in samples collected after noon than before noon. Local population density, beach cloud cover, and beach wave height were significantly correlated with SA or MRSA detection frequency. The Panton-Valentine leukocidin gene, associated with community-acquired MRSA, was detected in 12 out of 27 potential MRSA samples. The femA gene was detected less frequently at beaches that met US enterococci criteria or EU enterococci ‘excellent’ recreational water quality, but was not related to Escherichia coli-defined criteria. Escherichia coli is often the only indicator used to determine water quality at US beaches, given the economic and healthcare burden that can be associated with infections caused by SA and MRSA, monitoring of recreational waters for non-fecal bacteria such as staphylococci and/or SA may be warranted.

  4. Community acquired pneumonia with shock, severe hypoxemia and leucopenia: Is the etiology methicillin resistant Staphylococci?

    Garima Kapoor

    2014-01-01

    Full Text Available A young, male presented to the emergency department with respiratory signs and symptoms along with shock and leucopenia. The suspected diagnosis of methicillin resistant Staphylococcus aureus (MRSA necrotizing pneumonia was confirmed later radiographically and microbiologically. This entity is common in childhood, but rarely reported in adults. This form of pneumonia affects young individuals without any comorbid illness. This is the first reported case of necrotizing pneumonia caused by community acquired-MRSA from Indian subcontinent. The probability to predict etiology of pneumonia from clinical signs is low; yet in the presence of shock, severe hypoxemia and leucopenia suspicion of MRSA should be kept high and hence that prompt initiation of appropriate antimicrobials may reduce mortality.

  5. Homology of mecA gene in methicillin-resistant Staphylococcus haemolyticus and Staphylococcus simulans to that of Staphylococcus aureus.

    Ubukata, K; Nonoguchi, R; Song, M D; Matsuhashi, M; Konno, M

    1990-01-01

    A penicillin-binding protein of molecular weight 76,000 inducible by beta-lactams was detected in methicillin-resistant Staphylococcus haemolyticus and Staphylococcus simulans. DNA from these strains hybridized to the mecA gene from Staphylococcus aureus; however, the chromosomal HindIII fragments containing the mecA genes were 3.4 kilobases in S. haemolyticus and 4.3 kilobases in S. simulans.

  6. Detection of methicillin resistance and slime factor production of Staphylococcus aureus in bovine mastitis

    Alper Ciftci; Arzu Findik; Ertan Emek Onuk; Serap Savasan

    2009-01-01

    This study aimed to detect methicillin resistant and slime producing Staphylococcus aureus in cases of bovine mastitis. A triplex PCR was optimized targetting 16S rRNA, nuc and mecA genes for detection of Staphylococcus species, S. aureus and methicillin resistance, respectively. Furthermore, for detection of slime producing strains, a PCR assay targetting icaA and icaD genes was performed. In this study, 59 strains were detected as S. aureus by both conventional tests and PCR, and 13 of them...

  7. In vitro phagocytosis of methicillin resistant and methicillin sensitive staphylococcus aureus by human polymorphonuclear leucocytes

    Staphylococcus aureus is a gram positive bacterium that causes a number of diseases such as abscesses, infective endocarditis, septic arthritis, etc. It is acquiring resistance against many antibiotics like methicillin; therefore its control is becoming increasingly difficult. Peripheral blood phagocytes particularly polymorphonuclear leucocytes play an important role in the protective mechanisms against these organisms. Phagocytes interact with bacteria and phagocytose these microorganisms to kill them. Phenotypically different isolates of Staphylococcus aureus including methicillin resistant Staphylococcus aureus (MRSA) and methicillin sensitive Staphylococcus aureus (MSSA) were collected from various hospitals of Lahore, Pakistan. Fresh polymorphonuclaer leucocytes were obtained from healthy individuals by centrifugation using Ficol-Hypaque gradient combined with dextran sedimentation. Microbiological method was used for the determination of phagocytic index of phenotypic variants of Staphylococcus aureus. A significant difference was observed between the phagocytic index of both bacterial groups. MSSA group showed the Mean+-SD of 79.46%+-3.9 while MRSA group showed 72.35%+-2.5. Significant difference in phagocytic index indicates that it can be one of the mechanisms of MRSA to evade host immune system as compare to MSSA. (author)

  8. Presence of the Panton-Valentine Leukocidin Genes in Methicillin-Resistant Staphylococcus aureus Is Associated with Severity and Clinical Outcome of Hospital-Acquired Pneumonia in a Single Center Study in China.

    Zhang, Chuanling; Guo, Liang; Chu, Xu; Shen, Limeng; Guo, Yuanyu; Dong, Huali; Mao, Jianfeng; van der Veen, Stijn

    2016-01-01

    The Panton-Valentine leukocidin (PVL) genes of methicillin-resistant Staphylococcus aureus (MRSA) have previously been associated with severe infections. Here, the impact of the PVL genes on severity of disease and clinical outcome of patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) due to MRSA was investigated in a single center observational study in a hospital in China. HAP due to MRSA was diagnosed in 100 patients and 13 of the patients were PVL positive, while VAP was diagnosed in 5 patients and 2 were PVL positive. The PVL positive patient group showed a significantly higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (14.3 ±7.8 vs. 10.1 ±4.7, P = 0.005) and significantly more patients with CRP levels >80 mg/L (8/15 vs. 12/90, P = 0.006) or WBC counts >15x109/L (7/15 vs. 12/90, P = 0.006), indicating that the severity of disease is affected by the presence of the PVL genes. The outcome of the study was defined by 30-day mortality. Four (27%) of the PVL positive patients and four (4%) of the PVL negative patients died within 30 days (P = 0.01, Fisher exact test). Kaplan-Meier survival curves were generated for the PVL positive and PVL negative patient groups, which differed significantly (P = 0.003). Among the patients that died, the mean interval between diagnosis and death was shorter for the PVL positive patients (9.3 ±5.6 vs. 40.8 ±6.6 days, P = 0.013). Further analysis within the HAP and VAP patient groups showed that the presence of PVL in MRSA impacted the severity of disease and clinical outcome of HAP, but for VAP the number of patients included in the study was too low. In conclusion, in this single center study in a Chinese hospital the presence of the PVL genes in MRSA impacted the severity of disease and clinical outcome in patients with HAP due to MRSA. PMID:27249225

  9. Carriage of methicillin-resistant Staphylococcus pseudintermedius in small animal veterinarians

    Paul, Narayan Chandra; Moodley, Arshnee; Ghibaudo, G.;

    2011-01-01

    Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is increasingly reported in small animals and cases of human infections have already been described despite its recent emergence in veterinary practice. We investigated the prevalence of MRSP and methicillin-resistant Staphylococcus...... aureus (MRSA) among small animal dermatologists attending a national veterinary conference in Italy. Nasal swabs were obtained from 128 veterinarians, seven of which harboured MRSP (n = 5; 3.9%) or MRSA (n = 2; 1.6%). A follow-up study of two carriers revealed that MRSP persisted for at least 1 month in...... rized by spa typing. Methicillin-resistant isolates were further typed by antimicrobial susceptibility testing, SCCmec and multi-locus sequence typing. Two lineages previously associated with pets were identified among the five MRSP isolates; the European epidemic clone ST71-SCCmec II-III and ST106...

  10. Methicillin-resistant Staphylococcus aureus colonization among pediatric health care workers from different outpatient settings

    Immergluck, Lilly Cheng; Satola, Sarah W.; Jain, Shabnam; Courtney, McCracken; Watson, J. Reneé; Chan, Trisha; Traci, Leong; Gottlieb, Edward; Jerris, Robert C

    2013-01-01

    Staphylococcus aureus colonization rates in pediatric health care workers from different types of outpatient settings were determined from December 2008 through May 2010. Colonization rates for Staphylococcus aureus and, specifically, methicillin-resistant Staphylococcus aureus (MRSA) rates were similar to the rates that have been reported for the general population. The predominant MRSA pulsed-field gel electrophoresis type associated with colonization in these health care workers is not MRS...

  11. Identification of methicillin-resistant Staphylococcus aureus using an integrated and modular microfluidic system.

    Chen, Yi-Wen; Wang, Hong; Hupert, Mateusz; Soper, Steven A

    2013-02-21

    Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of hospital-acquired (HA-MRSA) infection worldwide. As a result, the rapid and specific detection of MRSA is crucial not only for early prevention of disease spread, but also for the effective treatment of these infections. We report here an integrated modular-based microfluidic system for MRSA identification, which can carry out the multi-step assay used for MRSA identification in a single disposable fluidic cartridge. The multi-step assay included PCR amplification of the mecA gene harboring methicillin resistance loci that can provide information on drug susceptibility, ligase detection reaction (LDR) to generate fluorescent ligation products appended with a zip-code complement that directs the ligation product to a particular address on a universal array containing zip-code probes and a universal DNA array, which consisted of a planar waveguide for evanescent excitation. The fluidic cartridge design was based on a modular format, in which certain steps of the molecular processing pipeline were poised on a module made from a thermoplastic. The cartridge was comprised of a module interconnected to a fluidic motherboard configured in a 3-dimensional network; the motherboard was made from polycarbonate, PC, and was used for PCR and LDR, while the module was made from poly(methylmethacrylate), PMMA, and contained an air-embedded waveguide serving as the support for the universal array. Fluid handling, thermal management and optical readout hardware were situated off-chip and configured into a small footprint instrument. In this work, the cartridge was used to carry out a multiplexed PCR/LDR coupled with the universal array allowed for simultaneous detection of five genes that encode for 16S ribosomal RNA (SG16S), protein A (spa), the femA protein of S. epidermidis (femA), the virulence factor of Panton-Valentine leukocidin (PVL) and the gene that confers methicillin resistance (mecA). Results

  12. Methicillin-resistant Staphylococcus aureus prevalence: Current susceptibility patterns in Trinidad

    Land Michael

    2006-05-01

    Full Text Available Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA has become one of the most widespread causes of nosocomial infections worldwide. Recently, reports have emerged that S. aureus strains recovered from community-acquired infections are also methicillin-resistant. This study was undertaken to analyze the prevalence of methicillin resistance among isolates at a regional hospital in Trinidad, and document the current resistance profile of MRSA and methicillin-sensitive Staphylococcus aureus (MSSA to the commonly used anti-staphylococcal agents. Methods Over a 6-year period we analyzed 2430 isolates of S. aureus strains recovered from various clinical sources, from hospital and community practices. Antimicrobial susceptibility testing was done according to guideline recommendations of the National Committee for Clinical Laboratory Standards. Results The prevalence of MRSA from surgical/burn wounds, urine and pus/abscess were 60.1%, 15.5% and 6.6%, respectively. The major sources of MSSA were surgical/burn wounds, pus/abscess and upper respiratory tract specimens with rates of 32.9%, 17.1% and 14.3%, respectively. The greatest prevalence of resistance of MRSA was seen for erythromycin (86.7%, and clindamycin (75.3%. Resistance rates among MSSA were highest for ampicillin (70%. Resistance rates for tetracycline were similar among both MRSA (78.7% and MSSA (73.5%. The MRSA recovery rates from nosocomial sources (20.8% was significantly higher than that of previous years (12.5% (p Conclusion The prevalence of MRSA in the hospital increased from 12.5% in 1999 to 20.8% in 2004. Most isolates were associated with infected surgical/burn wounds which may have become infected via the hands of HCPs during dressing exercises. Infection control measures aimed at the proper hand hygiene procedures may interrupt the spread of MRSA. HCPs may also be carriers of MRSA in their anterior nares. Surveillance cultures of both patients and HCPs may help

  13. Dissemination of a single clone of methicillin-resistant Staphylococcus aureus among Turkish hospitals

    A.F. van Belkum (Alex); R.P.A.J. Verkooyen (Roel); S.C. Sacilik; C. Cokmus; H.A. Verbrugh (Henri); W.B. van Leeuwen (Willem)

    1997-01-01

    textabstractA collection of 39 methicillin-resistant Staphylococcus aureus (MRSA) stains derived from six different hospitals in Ankara and one hospital in Barsa, Turkey, were analyzed by multiple genotyping. In agreement with the other genotyping assays, pulsed-field g

  14. Preventing Community-Associated Methicillin-Resistant "Staphylococcus aureus" among Student Athletes

    Many, Patricia S.

    2008-01-01

    Methicillin-resistant "Staphylococcus aureus" (MRSA) was once thought to be a bacterium causing infections in only hospitalized patients. However, a new strain of MRSA has emerged among healthy individuals who have not had any recent exposure to a hospital or to medical procedures. This new strain is known as "community-associated MRSA". Studies…

  15. Methicillin-Resistant Staphylococcus aureus Prevalence among Captive Chimpanzees, Texas, USA, 2012 1

    Hanley, Patrick W.; Barnhart, Kirstin F.; Christian R. Abee; Lambeth, Susan P.; Weese, J Scott

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infection in humans and animals is concerning. In 2012, our evaluation of a captive chimpanzee colony in Texas revealed MRSA prevalence of 69%. Animal care staff should be aware of possible zoonotic MRSA transmission resulting from high prevalence among captive chimpanzees.

  16. A case of methicillin-resistant Staphylococcus pseudintermedius (MRSP) pyoderma in a Labrador retriever dog

    Wan, Jennifer

    2014-01-01

    An 8-year-old, neutered male Labrador retriever dog with generalized pruritis had a history of recurring atopic dermatitis and superficial pyoderma. Cocci and yeast were found on cytology and methicillin-resistant Staphylococcus pseudintermedius was cultured. A regimen of marbofloxacin, dexamethasone, ketoconazole, and cyclosporine in addition to bathing with 2% chlorhexidine shampoo resulted in marked improvement.

  17. Frequent emergence and limited geographic dispersal of methicillin-resistant Staphylococcus aureus

    Nübel, Ulrich; Roumagnac, Philippe; Feldkamp, Mirjam;

    2008-01-01

    A small number of clonal lineages dominates the global population structure of methicillin-resistant Staphylococcus aureus (MRSA), resulting in the concept that MRSA has emerged on a few occasions after penicillinase-stable beta-lactam antibiotics were introduced to clinical practice, followed...

  18. Nosocomial transmission of community-associated methicillin-resistant Staphylococcus aureus in Danish Hospitals

    Hetem, David J; Westh, Henrik; Boye, Kit;

    2012-01-01

    The emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has changed the epidemiology of MRSA infections worldwide. In contrast to hospital-associated MRSA (HA-MRSA), CA-MRSA more frequently affects healthy individuals, both with and without recent healthcare...

  19. Heterogeneity among methicillin-resistant Staphylococcus aureus from Italian pig finishing holdings

    Battisti, A.; Franco, A.; Merialdi, G.;

    2010-01-01

    A survey for methicillin-resistant Staphylococcus aureus (MRSA) in finishing pig holdings was carried out in Italy in 2008. MRSA isolates were characterised by spa-. SCCmec- and antimicrobial susceptibility typing. A prevalence of 38% (45/118, 95% CI 29.4-46.9%) positive holdings was observed...

  20. Control of a methicillin-resistant Staphylococcus aureus (MRSA) outbreak in a day-care institution

    Jensen, Jens Ulrik; Jensen, ET; Larsen, AR;

    2006-01-01

    This article describes an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) in two institutions for multi-handicapped children in Copenhagen. The aim of the study was to determine whether it was possible to eradicate MRSA in a setting with multi-handicapped children and staff where...

  1. Simplified screening in an emergency department detected methicillin-resistant Staphylococcus aureus

    Mogensen, Christian Backer; Kjældgaard, Poul; Jensen, Charlotte;

    2016-01-01

    INTRODUCTION: All patients admitted to Danish hospitals are screened for methicillin-resistant Staphylococcus aureus (MRSA) by a questionnaire consisting of 19 questions issued by the Danish Health and Medicines Authority (DHMA). This study aimed to evaluate which of the questions were most useful...

  2. Carriage of methicillin-resistant Staphylococcus aureus by healthy companion animals

    Methicillin-resistant Staphylococcus aureus (MRSA) is a significant human pathogen and has also been associated with wounded or ill companion animals. Healthy animals may also harbor MRSA without presenting any symptoms, but little is known about the prevalence of MRSA among these animals. Therefo...

  3. The Epidemiology of Methicillin-Resistant Staphylococcus aureus (MRSA) in Germany

    Koeck, Robin; Mellmann, Alexander; Schaumburg, Frieder; Friedrich, Alexander W.; Kipp, Frank; Becker, Karsten

    2011-01-01

    Background: For decades, methicillin-resistant Staphylococcus aureus (MRSA) has been a major cause of infection in hospitals and nursing homes (health care-associated MRSA, HA-MRSA). Beginning in the late 1990s, many countries have also experienced a rising incidence of MRSA infection outside of the

  4. Pig-associated methicillin-resistant Staphylococcus aureus: Family transmission and severe pneumonia in a newborn

    Hartmeyer, Gitte Nyvang; Gahrn-Hansen, Bente; Skov, Robert L;

    2010-01-01

    Abstract Carriage of pig-associated methicillin-resistant Staphylococcus aureus (MRSA) is known to occur in pig farmers. Zoonotic lineages of MRSA have been considered of low virulence and with limited capacity for inter-human spread. We present a case of family transmission of pig-associated MRSA...

  5. Nosocomial Infections and Drug Susceptibility Patterns in Methicillin Sensitive and Methicillin Resistant Staphylococcus aureus

    Sharma, Nitish Kumar; Garg, Raina; Baliga, Shrikala; Bhat K., Gopalkrishna

    2013-01-01

    Aim: Staphylococcus aureus is one of the leading causes of nosocomial infections and is known for its ability to develop resistance to antibiotics. The drug susceptibility pattern of Methicillin Sensitive S. aureus (MSSA) and Methicillin Resistant S. aureus (MRSA) may vary.

  6. Rapid first-line discrimination of methicillin resistant Staphylococcus aureus strains using MALDI-TOF MS

    Østergaard, Claus; Grønvall Kjær Hansen, Sanne; Møller, Jens K

    2015-01-01

    Fast and reliable discrimination of methicillin-resistant Staphylococcus aureus (MRSA) isolates is essential in identifying an outbreak. Molecular typing methods, such as S. aureus protein A (spa) typing, multi locus sequence typing (MLST) and pulse field gel electrophoresis (PFGE) are generally...

  7. The Costs and Consequences of Methicillin-Resistant Staphylococcus aureus Infection Treatments in Canada

    Andrew J Rosner

    2004-01-01

    Full Text Available BACKGROUND: A multinational randomized controlled trial has shown a trend toward early discharge of patients taking oral linezolid versus intravenous vancomycin (IV in the treatment of methicillin-resistant Staphylococcus aureus (MRSA infections. Infection treatments resulting in shorter hospitalization durations are associated with cost savings from the hospital perspective.

  8. Rapid increase of genetically diverse methicillin-resistant Staphylococcus aureus, Copenhagen, Denmark

    Bartels, Mette Damkjaer; Boye, Kit; Rhod Larsen, Anders;

    2007-01-01

    In Copenhagen, methicillin-resistant Staphylococcus aureus (MRSA) accounted for <15 isolates per year during 1980-2002. However, since 2003 an epidemic increase has been observed, with 33 MRSA cases in 2003 and 110 in 2004. We analyzed these 143 cases epidemiologically and characterized isolates ...

  9. Antibacterial activity of extracts of Acacia aroma against methicillin-resistant and methicillin-sensitive Staphylococcus

    C.M. Mattana

    2010-10-01

    Full Text Available Antibacterial activity of organic and aqueous extracts of Acacia aroma was evaluated against methicillin-resistant Staphylococcus aureus (MRSA, methicillin sensitive Staphylococcus aureus (MSSA and methicillin-resistant Staphylococcus epidermidis. Inhibition of bacterial growth was determined using agar diffusion and bioautographic methods. Among all assayed organic extracts only ethanolic and ethyl acetate extracts presented highest activities against all tested Staphylococcus strains with minimal inhibitory concentration (MIC values ranging from 2.5 to 10 mg/ml and from 2.5 to 5 mg/ml respectively. The aqueous extracts show little antibacterial activity against Staphylococcus strains. The bioautography assay demonstrated well-defined growth inhibition zones against S. aureus in correspondence with flavonoids and saponins. A. aroma would be an interesting topic for further study and possibly for an alternative treatment for skin infections.

  10. Clindamycin-susceptibility Rates of Methicillin-resistant Staphylococcus aureus Varies by Infection Type in Pediatric Patients.

    Li, Amanda; Selvarangan, Rangaraj; Ogden, Richard; French, Brandon; Yu, Diana

    2016-08-01

    Hospital-wide antibiograms provide general susceptibility patterns. Specific antibiograms were created for methicillin-resistant Staphylococcus aureus isolates based on infection process and epidemiology. Using clinical microbiology laboratory data and patient profiles, high clindamycin resistance rates were seen for nonskin and soft tissue infections and noncommunity-associated methicillin-resistant S. aureus isolates. PMID:27164465

  11. New antimicrobial combinations: substituted chalcones- oxacillin against methicillin resistant Staphylococcus aureus

    Juan Manuel Talia

    2011-06-01

    Full Text Available Staphylococcus aureus, the most virulent Staphylococcus species, is also the prevalent pathogen isolated from hospitalized patients and the second most common from patients in outpatient settings. In general, bacteria have the genetic ability to transmit and acquire resistance to drugs, which are utilized as therapeutic agents. Related studies of antimicrobial activity indicate that crude extracts containing flavonoids, triterpenes and steroids have showed significative activity against several Staphylococcus aureus strains. Combination effects between flavonoids and antibiotics also have been reported. The aim of the present work was to investigate in vitro synergism between several chalcones substituted in combination with oxacillin, an antibiotic used conventionally against S. aureus ATCC 43 300 that is resistant to meticillin, using the kinetic turbidimetric method developed earlier. The results were satisfactory for all assayed combinations and in accordance with the mechanism of bacteriostatic inhibition previously proposed, except for 2´,4´-dihydroxy-3´-methoxychalcone - oxacillin. The best combination was 2´,3´-dihydroxychalcone - oxacillin (MIC: 11.2 μg/mL. Further investigations are needed to characterize the interaction mechanism with antibiotics. Thus, chalcones - oxacillin combination could lead to the development of new antibiotics against methicillin resistant S. aureus infection.

  12. The pls Gene Found in Methicillin-Resistant Staphylococcus aureus Strains Is Common in Clinical Isolates of Staphylococcus sciuri

    Juuti, Katri; Ibrahem, Salha; Virolainen-Julkunen, Anni; Vuopio-Varkila, Jaana; Kuusela, Pentti

    2005-01-01

    pls, a gene found in type I staphylococcal cassette chromosome mec (SCCmec) regions of methicillin-resistant Staphylococcus aureus strains, was present in 12 of the 15 human clinical Staphylococcus sciuri isolates studied. Pls was expressed in the S. sciuri isolates, although at a lower level than in S. aureus. Other parts of SCCmec could also be found in the S. sciuri genome.

  13. Survey of Staphylococcus isolates among hospital personnel, environment and their antibiogram with special emphasis on methicillin resistance

    Shobha K

    2005-01-01

    Full Text Available The objective of this study was to find the prevalence of Staphylococcus spp. carriage among hospital personnel and hospital environment and their antibiogram with special emphasis on methicillin resistance. A total of 205 samples from hospital personnel and environment were collected from casualty, oncology and multidisciplinary cardiac unit ward of Kasturba Medical College Hospital, Manipal. Samples were collected using sterile cotton wool swabs and inoculated into brain heart infusion broth. Subcultures were done onto blood agar and MacConkey′s agar. Isolates were identified by standard methods up to species level. Antimicrobial susceptibility test was performed according to standardized disc diffusion Kirby-Bauer method. Each of the isolates was screened for methicillin resistance using oxacillin disc on Mueller Hinton agar plate followed by MIC for methicillin and cefoxitin susceptibility test by disc diffusion method. Sixty five out of 205 strains (31.7% were Staphylococcus spp. and all of them were coagulase negative. Most of the strains belonged to S.epidermidis 49.23%(32/65 followed by S. saprophyticus 26.15%(17/65. Maximum isolates of S.epidermidis were from anterior nares 28.12%(9/32 strains of S.epidermidis . Highest number of methicillin resistant coagulase negative strains (3/9, 33.33% were isolated from stethoscope of multidisciplinary cardiac unit ward followed by carriers in the anterior nares (2/9, 22.22%. Methicillin resistant coagulase negative staphylococci are prevalent in anterior nares of hospital personnel and in the hospital environment thereby providing a definite source for hospital acquired infection. All isolates were sensitive to vancomycin, ciprofloxacin and amikacin.

  14. Prevalence of methicillin-resistant Staphylococcus haemolyticus in companion animals: a cross-sectional study

    Ruzauskas, Modestas; Siugzdiniene, Rita; Klimiene, Irena; Virgailis, Marius; Mockeliunas, Raimundas; Vaskeviciute, Lina; Zienius, Dainius

    2014-01-01

    Background Among coagulase-negative staphylococci, Staphylococcus haemolyticus is the second most frequently isolated species from human blood cultures and has the highest level of antimicrobial resistance. This species has zoonotic character and is prevalent both in humans and animals. Recent studies have indicated that methicillin-resistant S. haemolyticus (MRSH) is one of the most frequent isolated Staphylococcus species among neonates in intensive care units. The aim of this study was to ...

  15. Prevalence of Community-Associated Methicillin-Resistant Staphylococcus aureus in Patients with Cystic Fibrosis▿

    Goodrich, Jennifer S.; Sutton-Shields, Tameaka N.; Kerr, Alan; Wedd, Joel P.; Miller, Melissa B.; Gilligan, Peter H.

    2009-01-01

    We prospectively determined the prevalence of community-associated Staphylococcus aureus in a large cystic fibrosis (CF) center between October 2005 and October 2007. We found that 2.7% (19/707) of the CF patients who had cultures during the study period were infected with this organism, representing 14% of the total methicillin-resistant Staphylococcus aureus strains (n = 140) recovered from the patient population during the study period.

  16. Comparison of two different sensitivity testing agard for detecting methicillin resistance in staphylococcus aureus

    To compare the accuracy of Mueller-Hinton agar and Isosensitest agar using cefoxitin disc for detecting methicillin resistant Staphylococcus aureus using mecA gene PCR assay as gold standard. One hundred clinical isolates of Staphylococcus aureus were evaluated; 64 MRSA (methicillin resistant Staphylococcus aureus) and 36 MSSA (methicillin sensitive Staphylococcus aureus) by mecA PCR assay. All the isolates were tested with cefoxitin 30 macro g disc using semi-confluent growth on Mueller-Hinton agar as well as on Iso-sensitest agar in ambient air at 35-37degree C after an overnight incubation as per recommendations of Clinical and Laboratory Standard Institute. Following diameters provided the best sensitivity and specificity without substantial overlapping between the zones of resistant and sensitive isolates; Mueller-Hinton agar: R/sup 2/ 20 mm (sensitivity 100% and specificity 100%), S/sup 3/ 22 mm (sensitivity 97.2% and specificity 100%), and Iso-sensitest agar: R/sup 2/ 26 mm (sensitivity 100% and specificity100%), S/sup 3/ 26 mm (sensitivity 100% and specificity 100%). High accuracy was obtained with cefoxitin disc on both media. Performance of both media was equally convincing for reliable prediction of methicillin resistance in Staphylococcus aureus by placing cefoxitin 30 macro g disc on either of these in routine susceptibility testing. (author)

  17. Student Self-Screening for Methicillin-Resistant Staphylococcus Aureus (MRSA) Nasal Colonization in Hand Hygiene Education

    Lum, Tia; Picardo, Kristin; Westbay, Theresa; Barnello, Amber; Fine, Lynn; Lavigne, Jill

    2014-01-01

    Objective. To determine the feasibility and effectiveness of adding a hand hygiene exercise in self-screening for Methicillin-Resistant Staphylococcus Aureus (MRSA) nasal colonization to a health care delivery course for first-year pharmacy (P1) students.

  18. Determination of methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteria in blood by capillary zone electrophoresis

    Horká, M. (Marie); Tesařová, M. (Marie); Karásek, P. (Pavel); Růžička, F.; Holá, V.; Sittová, M.; Roth, M

    2015-01-01

    We used capillary zone electrophoresis in supercritical water-etched and modified fused silica capillaries to separate methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteria from clinical samples of whole blood.

  19. Inactivating Methicillin Resistant Staphylococcus aureus (MRSA) and Other Pathogens by Bacteriocins OR-7 and E 50-52.

    Worldwide, reports document the increasing frequency of methicillin resistant Staphylococcus aureus (MRSA) infections. Other human pathogens are recognized as unresponsive to antibiotics of last resort. These previously treatable infections now account for increased numbers of human disease and de...

  20. Characterization and lytic activity of methicillin-resistant Staphylococcus aureus(MRSA phages isolated from NICU

    Golnar Rahimzadeh

    2016-06-01

    Full Text Available Background Methicillin-resistant Staphylococcus aureus (MRSA is a well-known pathogen that causes serious diseases in humans. As part of the efforts to control this pathogen, an isolated bacteriophage, Siphoviridae, which specifically targets Methicillin-resistant Staphylococcus aureus (MRSA, was characterized. Aims The objective of this study was to characterize of a virulent bacteriophage (Siphoviridae isolated from a NICU bathroom sink. Methods The MRSA strain was isolated from patient blood. The isolated strain was confirmed as MRSA using conventional methods. Phages were isolated from a NICU bathroom sink and activity was lytic as determined by spot test. Titer phage lysate was measured by the Double Layer Agar (DLA technique. The morphology was found with electron microscopy. The single-step growth curve was plotted. Results Electron microscopy showed the phage as a member of the family Siphoviridae, serogroup A and F. The isolated phage was capable of lytic activity against methicillin-resistant Staphylococcus aureus (MRSA strain as shown by spot test. By DLA, the titre of the phages was determined to be 10×108PFU/ml. The single-step growth curve showed that the latent period of the isolated bacteriophage was 30 min and the total number of viable progeny per infected host, burst size, was 2600 PFU/infected host. Conclusion In this study, two phages were isolated and characterized from a NICU bathroom sink, from the Siphoviridae family, which specifically targetsmethicillin-resistant Staphylococcus aureus (MRSA.

  1. Community acquired pneumonia with shock, severe hypoxemia and leucopenia: Is the etiology methicillin resistant Staphylococci?

    Garima Kapoor; Saurabh Saigal; Jai Prakash Sharma; Mohan Gurjar

    2014-01-01

    A young, male presented to the emergency department with respiratory signs and symptoms along with shock and leucopenia. The suspected diagnosis of methicillin resistant Staphylococcus aureus (MRSA) necrotizing pneumonia was confirmed later radiographically and microbiologically. This entity is common in childhood, but rarely reported in adults. This form of pneumonia affects young individuals without any comorbid illness. This is the first reported case of necrotizing pneumonia caused by com...

  2. European ST80 community-associated methicillin-resistant Staphylococcus aureus orbital cellulitis in a neonate

    Tsironi Evangelia E

    2012-05-01

    Full Text Available Abstract Background Methicillin-resistant Staphylococcus aureus is a serious cause of morbidity and mortality in hospital environment, but also, lately, in the community. This case report is, to our knowledge, the first detailed description of a community-associated methicillin-resistant S. aureus ST80 orbital cellulitis in a previously healthy neonate. Possible predisposing factors of microbial acquisition and treatment selection are also discussed. Case presentation A 28-day-old Caucasian boy was referred to our hospital with the diagnosis of right orbital cellulitis. His symptoms included right eye proptosis, periocular edema and redness. Empirical therapy of intravenous daptomycin, rifampin and ceftriaxone was initiated. The culture of pus yielded a methicillin-resistant S. aureus isolate and the molecular analysis revealed that it was a Panton-Valentine leukocidine-positive ST80 strain. The combination antimicrobial therapy was continued for 42days and the infection was successfully controlled. Conclusions Clinicians should be aware that young infants, even without any predisposing condition, are susceptible to orbital cellulitis caused by community-associated methicillin-resistant S. aureus. Prompt initiation of the appropriate empirical therapy, according to the local epidemiology, should successfully address the infection, preventing ocular and systemic complications.

  3. Infections of diabetic foot ulcers with methicillin-resistant Staphylococcus aureus.

    Cervantes-García, Estrella; García-González, Rafael; Reséndiz-Albor, Aldo; Salazar-Schettino, Paz Maria

    2015-03-01

    Infected diabetic foot is the most common reason for hospitalization and complications in patients with type 2 diabetes mellitus (DM2). Methicillin-resistant Staphylococcus aureus (MRSA) is frequently isolated from such lesions, and its presence is growing, seriously deteriorating the infected patient's quality of life. The aim of this study was to assess the prevalence of MRSA as well as other microbiota in 100 patients diagnosed with (DM2) and with infected foot ulcers at the Hospital General de Mexico. The main results obtained show a prevalence of Staphylococcus aureus (42%), followed by Escherichia coli (36%) and, in lower percentages, other bacteria. MRSA was predominant (34%), and we conclude that the use of cefoxitin instead of oxacillin as the first-choice antibiotic has an advantage because it is a better inducer of methicillin-resistance expression. PMID:25573977

  4. Small colony variant of methicillin-resistant Staphylococcus aureus isolated from an osteomyelitis case

    Server Yagci

    2013-06-01

    Full Text Available Methicillin-resistant Staphylococcus aureus small colony variants may cause soft tissue infections. However, any casepresenting with soft tissue abscess after a fracture surgery is not been reported yet. In this report; a case of methicillinresistantS. aureus small colony variant that was isolated from a 68-years-old man who has a fracture surgery history andrecurrent abscess developing in his left thigh was reported. This variant was recovered from aspiration material of theopen wound. Daptomycin was used successfully in the treatment of the bacterial infection which is resistant to rifampin.J Microbiol Infect Dis 2013; 3(2: 89-92Keywords: Small colony variant, methicillin-resistant Staphylococcus aureus, recurrent abscess

  5. Methicillin-resistant Staphylococcus aureus colonization and infection risks from companion animals: current perspectives

    Petinaki E

    2015-11-01

    Full Text Available Efthimia Petinaki,1 Iris Spiliopoulou21Department of Microbiology, School of Medicine, University of Thessalia, Larissa, 2Department of Microbiology, School of Medicine, University of Patras, Patras, GreeceAbstract: Methicillin-resistant Staphylococcus aureus (MRSA remains one of the most virulent human pathogens and has also recently been recognized as such in the veterinary settings. Companion animals, including dogs, cats, horses, small exotic animals, wildlife animals, and livestock, may constitute a reservoir for MRSA transmission to humans and vice versa. The evolution, emergence, and risk factors for MRSA transmission among colonized or infected animals are reviewed in the present paper, and infection control practices are discussed.Keywords: methicillin-resistant Staphylococcus aureus, companion animals, close contacts

  6. A Survey of Staphylococcus sp and its Methicillin Resistance aboard the International Space Station

    Bassinger, V. J.; Fontenot, S. L.; Castro, V. A.; Ott, C.; Healy, M.; Pierson, D. L.

    2004-01-01

    Background: Within the past few years, methicillin-resistant Staphylococcus aureus has emerged in environments with susceptible hosts in close proximity, such as hospitals and nursing homes. As the International Space Station (ISS) represents a semi-closed environment with a high level of crewmember interaction, an evaluation of isolates of clinical and environmental Staphylococcus aureus and coagulase negative Staphylococcus was performed to determine if this trend was also present in astronauts occupying ISS or on surfaces of the space station itself. Methods: Identification of isolates was completed using VITEK (GPI cards, BioMerieux), 16S ribosomal DNA analysis (MicroSeq 500, ABI), and Rep-PCR DNA fingerprinting (Divemilab, Bacterial Barcodes). Susceptibility tests were performed using VITEK (GPS-105 cards, BioMerieux) and resistance characteristics were evaluated by testing for the presence of the mecA gene (PBP2' MRSA test kit, Oxoid). Results: Rep-PCR analysis indicated the transfer of S. aureus between crewmembers and between crewmembers and ISS surfaces. While a variety of S. aureus were identified from both the crewmembers and environment, evaluations of the microbial population indicated minimal methicillin resistance. Results of this study indicated that within the semi-closed ISS environment, transfer of bacteria between crewmembers and their environment has been occurring, although there was no indication of a high concentration of methicillin resistant Staphylococcus species. Conclusions: While this study suggests that the spread of methicillin resistant S. aureus is not currently a concern aboard ISS, the increasing incidence of Earth-based antibiotic resistance indicates a need for continued clinical and environmental monitoring.

  7. The Rise of Methicillin-Resistant Staphylococcus aureus in U.S. Correctional Populations

    Malcolm, Bianca

    2011-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an emerging threat to public health, especially in correctional settings. Outbreaks have been seen in jails and prisons in Mississippi, California, Texas, and Georgia in recent years. Also, many correctional settings have seen an increase in MRSA infection greater than in the general population. This article examines the lessons that have been learned about MRSA in correctional settings and ponders what is yet to be learned about this dise...

  8. Risk Factors for Methicillin Resistant Staphylococcus aureus Nasal Colonization of Healthy Children

    Soltani, Babak; Abbas TAGHAVI ARDAKANI; Moravveji, Alireza; Erami, Mahzad; Haji Rezaei, Mostafa; Moniri, Rezvan; Namazi, Mansoor

    2014-01-01

    Background: Nasal colonization of healthy children with Staphylococcus aureus is an important risk factor for different infections. Detection of colonized individuals with methicillin resistant S. aureus (MRSA) and its eradication is the proper prevention strategy for infection spread in the community and health-care centers. Objectives: The aim of this study was to determine the prevalence, associated risk factors and antibiotic resistance pattern among healthy children who were nasal carrie...

  9. Melittin, a honeybee venom-derived antimicrobial peptide, may target methicillin-resistant Staphylococcus aureus

    Choi, Ji Hae; JANG, A YEUNG; Lin, Shunmei; Lim, Sangyong; Kim, Dongho; Park, Kyungho; Han, Sang-Mi; YEO, JOO-HONG; Seo, Ho Seong

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is difficult to treat using available antibiotic agents. Honeybee venom has been widely used as an oriental treatment for several inflammatory diseases and bacterial infections. The venom contains predominantly biologically active compounds, however, the therapeutic effects of such materials when used to treat MRSA infections have not been investigated extensively. The present study evaluated bee venom and its principal active component, meli...

  10. Role of Berberine in the Treatment of Methicillin-Resistant Staphylococcus aureus Infections

    Ming Chu; Ming-bo Zhang; Yan-chen Liu; Jia-rui Kang; Zheng-yun Chu; Kai-lin Yin; Ling-yu Ding; Ran Ding; Rong-xin Xiao; Yi-nan Yin; Xiao-yan Liu; Yue-dan Wang

    2016-01-01

    Berberine is an isoquinoline alkaloid widely used in the treatment of microbial infections. Recent studies have shown that berberine can enhance the inhibitory efficacy of antibiotics against clinical multi-drug resistant isolates of methicillin-resistant Staphylococcus aureus (MRSA). However, the underlying mechanisms are poorly understood. Here, we demonstrated that sub-minimum inhibitory concentrations (MICs) of berberine exhibited no bactericidal activity against MRSA, but affected MRSA b...

  11. Ceftaroline Fosamil Use in 2 Pediatric Patients With Invasive Methicillin-Resistant Staphylococcus aureus Infections

    Williams, Amanda W.; Newman, Patrick M; Ocheltree, Sara; Beaty, Rachel; Hassoun, Ali

    2015-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is one of the most common pathogens causing pediatric infections including skin and soft tissue infections, pyogenic arthritis, osteomyelitis, and septic shock. For decades, patients were treated with antibiotics such as vancomycin and clindamycin, but there is an increasing incidence of resistance to these traditional therapies. We describe 2 cases of patients with CA-MRSA invasive infections with bacteremia who exper...

  12. Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat

    Hady, Wessam Abdel; Bayer, Arnold S.; Xiong, Yan Q.

    2012-01-01

    Endovascular infections, including endocarditis, are life-threatening infectious syndromes1-3. Staphylococcus aureus is the most common world-wide cause of such syndromes with unacceptably high morbidity and mortality even with appropriate antimicrobial agent treatments4-6. The increase in infections due to methicillin-resistant S. aureus (MRSA), the high rates of vancomycin clinical treatment failures and growing problems of linezolid and daptomycin resistance have all further complicated th...

  13. Molecular characteristics of community-associated methicillin-resistant Staphylococcus aureus colonizing surgical patients in Greece.

    Hadjihannas, Linos; Psichogiou, Mina; Empel, Joanna; Kosmidis, Chris; Goukos, Dimitrios; Bouzala, Jina; Georgopoulos, Sotirios; Malhotra-Kumar, Surbhi; Harbarth, Stephan; Daikos, George L

    2012-12-01

    Fifty-one of 925 patients screened for methicillin-resistant Staphylococcus aureus (MRSA) upon admission to a surgical unit were MRSA carriers; 15 were classified as community- and 36 as hospital-associated-MRSA. Fourteen of 22 isolates typed by molecular methods belonged to the European clone ST80-IVc, 3 of which exhibited resistance to ≥3 non-β-lactam antibiotics. PMID:23021063

  14. Increasing the efficiency of a targeted methicillin-resistant Staphylococcus aureus screening program.

    Goldsack, Jennifer C; DeRitter, Christine; Power, Michelle; Spencer, Amy; Taylor, Cynthia L; Manta, Christine J; Kirk, Ryan; Drees, Marci L

    2016-01-01

    An interdisciplinary team implemented a screening program targeting patients with a history of methicillin-resistant Staphylococcus aureus (MRSA), to reduce unnecessary contact isolation. After converting from a 2-step culture-based protocol to single polymerase chain reaction (PCR) testing, we increased the efficiency of the screening program from 77% to 100%. Despite the higher cost of PCR-based testing, this program remained cost-saving. PMID:26769283

  15. Methicillin-resistant Staphylococcus non-aureus Infection in an Irradiated Rhesus Macaque (Macaca mulatta)

    Kolappaswamy, Krishnan; Shipley, Steven T; Tatarov, Ivan I; DeTolla, Louis J.

    2008-01-01

    We describe a case of methicillin-resistant Staphylococcus non-aureus infection in a rhesus macaque (Macaca mulatta). The nonhuman primate described was part of a research project that involved whole-body gamma irradiation and subsequently developed acute generalized dermatitis with skin dryness, peeling, and erythema around the eyes. After initial evaluation, which included microbiologic culture and 6 d of medical treatment, the animal was euthanized due to concern regarding a possible outbr...

  16. Evaluation of four phenotypic methods for the rapid identification of methicillin resistant Staphylococcus aureus

    Narasinga R. Bandaru; Srinivas Budati

    2016-01-01

    Background: Methicillin-resistant Staphylococcus aureus (MRSA), a superbug has been recognized as one of the major pathogens in hospitals as well as community settings. The prevalence of MRSA is 30 and ndash;70% and many studies have suggested an alarming rate of infections caused by this organism. In spite of modern diagnostic procedures and technological advancement, infections caused by MRSA still remain difficult to diagnose in developing countries like India. We tried to evaluate four ph...

  17. Classifying spa Types in Complexes Improves Interpretation of Typing Results for Methicillin-Resistant Staphylococcus aureus

    Ruppitsch, Werner; Indra, Alexander; Stöger, Anna; Mayer, Barbara; Stadlbauer, Silke; Wewalka, Günther; Allerberger, Franz

    2006-01-01

    A total of 382 isolates of methicillin-resistant Staphylococcus aureus originating from three Austrian regions and one adjacent Italian region (Vienna, Lower Austria, North Tyrol, and South Tyrol) were typed by DNA sequence analysis of the variable repeat region of the protein A gene (spa typing). The strain collection consisted of arbitrarily chosen isolates originating from clinical specimens taken in the years 2003 to 2005 at 17 hospitals. The most common spa types found were t001 (28.8% o...

  18. Sub-acute mastitis associated with Methicillin Resistant Staphylococcus aureus in a cow: A case report

    Duraisamy Chandrasekaran; Periasamy Venkatesan; Krishnasamy Gopalan Tirumurugaan; Balakrishnan Gowri; Subramanian Subapriya; Subramanium Thirunavukkarasu

    2014-01-01

    A 5-year old Holstein Friesian cross breed cow was presented to Madras Veterinary College Teaching Hospital with the history of reduced milk yield. Clinical examination of udder revealed normal milk color and soft udder. The milk pH was 7.0, with California Mastitis Test score 3+, Electrical Conductivity 270U, and Somatic Cell Count as 328,000. Isolation and identification of causative agent revealed Methicillin Resistant Staphylococcus aureus (MRSA) from the sub-acute mastitis sample. Agar d...

  19. Methicillin-resistant Staphylococcus sp. colonizing health care workers of a cancer hospital

    Dayane de Melo Costa; André Kipnis; Lara Stefânia Netto de Oliveira Leão-Vasconcelos; Larissa Oliveira Rocha-Vilefort; Sheila Araújo Telles; Maria Cláudia Dantas Porfírio Borges André; Anaclara Ferreira Veiga Tipple; Ana Beatriz Mori Lima; Nádia Ferreira Gonçalves Ribeiro; Mayara Regina Pereira; Marinésia Aparecida Prado-Palos

    2014-01-01

    The aim of the study was to analyze epidemiological and microbiological aspects of oral colonization by methicillin-resistant Staphylococcus of health care workers in a cancer hospital. Interview and saliva sampling were performed with 149 health care workers. Antimicrobial resistance was determined by disk diffusion and minimum inhibitory concentration. Polymerase Chain Reaction, Internal Transcribed Spacer-Polymerase Chain Reaction and Pulsed Field Gel Electrophoresis were performed for gen...

  20. Methicillin-Resistant Staphylococcus aureus in Saarland, Germany: The Long-Term Care Facility Study

    Nillius, Dorothea; von Müller, Lutz; Wagenpfeil, Stefan; Klein, Renate; Herrmann, Mathias

    2016-01-01

    Background Multiresistant organisms pose a threat for patients and care recipients. Control interventions need to be tailored to region, the type of institution considered, and risk factors. The German state of Saarland is ideally suited to study colonisation epidemiology throughout its various health and care institutions. After conclusion of a large admission prevalence study in acute care hospitals, we now performed a methicillin-resistant Staphylococcus aureus (MRSA) point prevalence stud...

  1. Improved understanding of factors driving methicillin-resistant Staphylococcus aureus epidemic waves

    Chatterjee SS; Otto M.

    2013-01-01

    Som S Chatterjee, Michael OttoPathogen Molecular Genetics Section, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USAAbstract: Methicillin-resistant Staphylococcus aureus (MRSA) remains one of the most important causes of nosocomial infections worldwide. Since the global spread of MRSA in the 1960s, MRSA strains have evolved with increased pathogenic potential. Notably, some strains are now capable of causing persistent infections not only in hospitalized patients but al...

  2. Ceftaroline Fosamil for Methicillin-Resistant Staphylococcus aureus Pulmonary Exacerbation in a Pediatric Cystic Fibrosis Patient

    Molloy, Leah; Snyder, Ashley Hall; Srivastava, Ruma; Rybak, Michael J.; McGrath, Eric

    2014-01-01

    Ceftaroline, an advanced generation cephalosporin with activity against methicillin-resistant Staphylococcus aureus (MRSA), may present a new therapeutic alternative for treating lung infections among patients with cystic fibrosis. We report a case of ceftaroline therapy in a pediatric patient with cystic fibrosis, whose dose was increased from 9.7 mg/kg/dose every 12 hours to 10.8 mg/kg/dose every 8 hours by using pharmacokinetic analyses.

  3. Antibacterial effects of Plectranthus amboinicus (Lour.) Spreng (Lamiaceae) in Methicillin resistant staphylococcus aureus (MRSA)

    Gurgel, Ana P.A.D.; Silva, Jackeline G. da; Grangeiro, Ana R.S.; Xavier, Haroudo Satiro; Oliveira, Rinalda Araújo Guerra de; Maria S.V. Pereira; Ivone A. Souza

    2009-01-01

    The present study describes some in vitro experiments with hydroalcoholic extract of leaves from Plectranthus amboinicus (Lour.) Spreng (Lamiaceae) in several Methicillin resistant Staphylococcus aureus (MRSA) strains in the attempt to determine whether the popular use corroborates with pharmacological properties. The antimicrobial activity was determined by the agar diffusion assay method. The evaluation of the minimum inhibitory concentration was determined using the agar dilution method...

  4. Methicillin-Resistant Staphylococcus aureus Associated with Animals and Its Relevance to Human Health

    AnnalisaPantosti

    2012-01-01

    Staphylococcus aureus is a typical human pathogen. Some animal S. aureus lineages have derived from human strains following profound genetic adaptation determining a change in host specificity. Due to the close relationship of animals with the environmental microbioma and resistoma, animal staphylococcal strains also represent a source of resistance determinants. Methicillin-resistant S. aureus (MRSA) emerged fifty years ago as a nosocomial pathogen but in the last decade it has also become...

  5. Kinase Inhibitors that Increase the Sensitivity of Methicillin Resistant Staphylococcus aureus to β-Lactam Antibiotics

    Jay Vornhagen; Kellie Burnside; Christopher Whidbey; Jessica Berry; Xuan Qin; Lakshmi Rajagopal

    2015-01-01

    Staphylococcus aureus are Gram-positive bacteria that are the leading cause of recurrent infections in humans that include pneumonia, bacteremia, osteomyelitis, arthritis, endocarditis, and toxic shock syndrome. The emergence of methicillin resistant S. aureus strains (MRSA) has imposed a significant concern in sustained measures of treatment against these infections. Recently, MRSA strains deficient in expression of a serine/threonine kinase (Stk1 or PknB) were described to exhibit increased...

  6. Epidemiological Characteristics of Methicillin-Resistant Staphylococcus aureus Isolates from Children with Eczematous Atopic Dermatitis Lesions▿

    Chung, Hee-Jung; Jeon, Hong-Seon; Sung, Heungsup; Kim, Mi-Na; Hong, Soo-Jong

    2008-01-01

    In this study, we investigated the rate of colonization of skin of children with atopic dermatitis (AD) by methicillin-resistant Staphylococcus aureus (MRSA) and characterized the isolates. Active skin lesions in pediatric AD patients were cultured with Rodac Staph (Komed, Korea). S. aureus isolates were examined for drug susceptibilities, analyzed for the eta, etb, tst, and pvl genes, and typed using agr polymorphism, pulsed-field gel electrophoresis of SmaI-restricted chromosomal DNA, and s...

  7. Community-Associated Methicillin-Resistant Staphylococcus aureus: Epidemiology and Clinical Consequences of an Emerging Epidemic

    David, Michael Z.; Daum, Robert S.

    2010-01-01

    Summary: Staphylococcus aureus is an important cause of skin and soft-tissue infections (SSTIs), endovascular infections, pneumonia, septic arthritis, endocarditis, osteomyelitis, foreign-body infections, and sepsis. Methicillin-resistant S. aureus (MRSA) isolates were once confined largely to hospitals, other health care environments, and patients frequenting these facilities. Since the mid-1990s, however, there has been an explosion in the number of MRSA infections reported in populations l...

  8. Methicillin-Resistant Staphylococcus aureus ST9 in Pigs in Thailand

    Jesper Larsen; Maho Imanishi; Soawapak Hinjoy; Prasit Tharavichitkul; Kwanjit Duangsong; Davis, Meghan F; Nelson, Kenrad E.; Larsen, Anders R.; Skov, Robert L.

    2012-01-01

    BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial and community-associated pathogen. Recently, livestock-associated MRSA (LA-MRSA) has emerged and disseminated in Europe and North America and now constitutes a considerable zoonotic burden in humans with risk factors of pig exposure, whereas the extent of the livestock reservoir is relatively unknown on other continents. METHODOLOGY/PRINCIPAL FINDINGS: From March through April 2011, MRSA was identified i...

  9. Daptomycin-nonsusceptible, vancomycin-intermediate, methicillin-resistant Staphylococcus aureus endocarditis

    Ryan Yu; Dale, Suzanne E; Deborah Yamamura; Vida Stankus; Christine Lee

    2012-01-01

    Due to the emergence of Staphylococcus aureus with reduced vancomycin susceptibility, newer antibiotics, including daptomycin, have been used to treat methicillin-resistant S aureus infections. Daptomycin is a cyclic lipopeptide that is approved to treat S aureus bacteremia and right-sided endocarditis, and reports of S aureus with reduced susceptibility to daptomycin are infrequent. To our knowledge, the present report describes the first Canadian case of daptomycin-nonsusceptible, vancomyci...

  10. Prevalence of Chlorhexidine-Resistant Methicillin-Resistant Staphylococcus aureus following Prolonged Exposure

    Schlett, Carey D.; Millar, Eugene V.; Crawford, Katrina B.; Cui, Tianyuan; Lanier, Jeffrey B.; Tribble, David R.; Ellis, Michael W.

    2014-01-01

    Chlorhexidine has been increasingly utilized in outpatient settings to control methicillin-resistant Staphylococcus aureus (MRSA) outbreaks and as a component of programs for MRSA decolonization and prevention of skin and soft-tissue infections (SSTIs). The objective of this study was to determine the prevalence of chlorhexidine resistance in clinical and colonizing MRSA isolates obtained in the context of a community-based cluster-randomized controlled trial for SSTI prevention, during which...

  11. The costs and consequences of methicillin-resistant Staphylococcus aureus infection treatments in Canada

    Rosner, Andrew J; Becker, Debbie L; Wong, Angelina H; Elizabeth Miller; John M Conly

    2004-01-01

    BACKGROUND: A multinational randomized controlled trial has shown a trend toward early discharge of patients taking oral linezolid versus intravenous vancomycin (IV) in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. Infection treatments resulting in shorter hospitalization durations are associated with cost savings from the hospital perspective.OBJECTIVE: To determine whether similar economic advantages are associated with oral linezolid, the costs and consequ...

  12. Mechanisms of methicillin-resistant Staphylococcus aureus pneumonia-induced intestinal epithelial apoptosis

    Perrone, Erin E.; Jung, Enjae; Breed, Elise; Dominguez, Jessica A.; Liang, Zhe; Clark, Andrew T.; Dunne, W. Michael; Burd, Eileen M.; Coopersmith, Craig M.

    2012-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia-induced sepsis is a common cause of morbidity in the intensive care unit. Although pneumonia is initiated in the lungs, extrapulmonary manifestations occur commonly. In light of the key role the intestine plays in the pathophysiology of sepsis, we sought to determine whether MRSA pneumonia induces intestinal injury. FVB/N mice were subjected to MRSA or sham pneumonia and sacrificed 24 hours later. Septic animals had a marked increas...

  13. Incidence of Community-associated Methicillin-resistant Staphylococcus aureus Infections in a Regional Hospital

    Kawabata, Hidenobu; Murakami, Manabu; Kisa, Kengo; Maezawa, Masaji

    2011-01-01

    Background and Objective: Since the early 2000s, the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections among the community of people lacking known healthcare risk factors has increased. This MRSA infection is referred to as community-associated MRSA (CA-MRSA) infection and is distinct from hospital-associated MRSA (HA-MRSA) infection, which occurs among people with known healthcare risk factors. Understanding the epidemiology of CA-MRSA infections is critical; however...

  14. Cross-Border Dissemination of Methicillin-Resistant Staphylococcus aureus, Euregio Meuse-Rhin Region

    Deurenberg, Ruud H.; Nulens, Eric; Valvatne, Havard; Sebastian, Silvie; Driessen, Christel; Craeghs, Jos; De Brauwer, Els; Heising, Bernhard; Kraat, Yvette J.; Riebe, Joachim; Stals, Frans S.; Trienekens, Thera A.; Scheres, Jacques; Friedrich, Alexander W.; van Tiel, Frank H.

    2009-01-01

    Because the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) differs among the 3 countries forming the Euregio Meuse-Rhin (EMR) region (Belgium, Germany, and the Netherlands), cross-border healthcare requires information about the spread of MRSA in the EMR. We investigated the emergence, dissemination, and diversity of MRSA clones in the EMR by using several typing methods. MRSA associated with clonal complexes 5, 8, 30, and 45 was disseminated throughout the EMR. Dutch isolat...

  15. Development and Evaluation of a Chromogenic Agar Medium for Methicillin-Resistant Staphylococcus aureus

    Perry, John D.; Davies, Amie; Butterworth, Lynne A.; Hopley, Andrew L. J.; Nicholson, Audrey; Gould, F. Kate

    2004-01-01

    We describe here the development and evaluation of MRSA ID, a new chromogenic agar medium for the specific isolation and identification of methicillin-resistant Staphylococcus aureus (MRSA). We used S. aureus ID (bioMérieux, La Balme Les Grottes, France) and supplemented it with various antimicrobials, including cefoxitin, ciprofloxacin, oxacillin, and methicillin. Cefoxitin proved to be superior to the other antimicrobials for the selection of MRSA from other strains of S. aureus. MRSA ID (c...

  16. Evaluation of a New Chromogenic Medium, MRSA Select, for Detection of Methicillin-Resistant Staphylococcus aureus▿

    Louie, Lisa; Soares, Deirdre; Meaney, Helen; Vearncombe, Mary; Simor, Andrew E

    2006-01-01

    We compared MRSA Select to mannitol-salt agar with 8 μg/ml cefoxitin for the detection of methicillin-resistant Staphylococcus aureus (MRSA) from 6,199 clinical samples submitted for MRSA screening. The sensitivities and specificities of MRSA Select and mannitol-salt agar with cefoxitin were 98% and 92% versus 90% and 78%, respectively (P < 0.0001). Most (96%) MRSA were detected after overnight incubation using MRSA Select.

  17. Predictive Value of Methicillin-Resistant Staphylococcus aureus (MRSA) Nasal Swab PCR Assay for MRSA Pneumonia

    Dangerfield, Benjamin; Chung, Andrew; Webb, Brandon; Seville, Maria Teresa

    2014-01-01

    Pneumonia due to methicillin-resistant Staphylococcus aureus (MRSA) is associated with poor outcomes and frequently merits empirical antibiotic consideration despite its relatively low incidence. Nasal colonization with MRSA is associated with clinical MRSA infection and can be reliably detected using the nasal swab PCR assay. In this study, we evaluated the performance of the nasal swab MRSA PCR in predicting MRSA pneumonia. A retrospective cohort study was performed in a tertiary care cente...

  18. The Increasing Problem of Wound Bacterial Burden and Infection in Acute and Chronic Soft-Tissue Wounds Caused by Methicillin-Resistant Staphylococcus aureus

    Demling, Robert H.; Waterhouse, Barbara

    2007-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has become a leading cause of colonization and infection in both acute and chronic soft-tissue wounds. Objective: Our objective is to define this current epidemic problem caused by both community-acquired MRSA (CA-MRSA) and hospital-acquired MRSA (HA-MRSA), focusing on the similarities and differences between these 2 isolates as well as the impact on wound management decisions. Methods: Methods used include a literature review on the growth o...

  19. Comparison of different phenotypic and genotypic methods for the detection of methicillin-resistant Staphylococcus aureus

    Abbas Farahani

    2013-01-01

    Full Text Available Background: Staphylococcus aureus is known as a powerful pathogen that causes various infections. Emergence of methicillin-resistant S. aureus (MSRA is responsible for nosocomial and community-acquired infections worldwide. Aims: The present study aimed to evaluate the performance and ability of eight different phenotypic and genotypic methods for the detection of MSRA. Materials and Methods: A total of 186 S. aureus isolates were defined as methicillin-susceptible S. aureus (MSSA; 95 and MSRA (91 using polymerase chain reaction (PCR as the gold standard. Susceptibility to methicillin was investigated using oxacillin, methicillin, cefotetan, cefoxitin, and cefmetazole disks, by oxacillin Adata Tab and strips. For all S. aureus isolates minimal inhibitory concentrations of oxacillin were determined using the broth microdilution method according to Clinical and Laboratory Standards Institute guidelines. Results: Among the diagnostic methods studied, broth microdilution and the cefoxitin disk had the highest specificity (98.9 and 94.7%, sensitivity (100 and 98.9%, and concordance with PCR results (98.9 and 93.6%. The cefotetan and cefmetazole disks had the lowest concordance with PCR results. Conclusion: Our results suggest that microdilution and cefoxitin disk methods have high sensitivities compared with other methods for detection of MSRA. The cefoxitin disk method may be preferred in clinical laboratories because it is easy to perform and does not require special equipment.

  20. Alternative agents to vancomycin for the treatment of methicillin-resistant Staphylococcus aureus infections.

    Culos, Kathryn A; Cannon, Joan P; Grim, Shellee A

    2013-01-01

    Resistant gram-positive infections, specifically methicillin-resistant Staphylococcus aureus (MRSA), carry an increased risk for morbidity and mortality. Historically, MRSA has been a cause of nosocomial infections, although recent reports have noted an increased prevalence in community-acquired MRSA infections. Vancomycin is the preferred agent to treat MRSA. However, cases of S. aureus with reduced susceptibility to vancomycin have been reported, prompting the need for alternative treatment options. In this review, we discuss the currently available agents with MRSA activity and those in development. Linezolid and quinupristin/dalfopristin have been demonstrated as effective although potential toxicities must be taken into consideration before their use. Daptomycin, tigecycline, telavancin, and ceftaroline are well tolerated but lack the clinical data to support a superior place in treatment over vancomycin. Several new agents in various stages of development have also demonstrated MRSA activity. Currently, vancomycin remains the gold-standard treatment option for MRSA infections. In situations that limit its use, consideration of patient-specific parameters, cost, and relevant clinical data demonstrating drug safety and efficacy should be employed for the selection of the appropriate alternative agent. PMID:21642833

  1. Prevalence of methicillin resistant Staphylococcus aureus [MRSA] colonization or carriage among health-care workers.

    Pathare, Nirmal A; Asogan, Harshini; Tejani, Sara; Al Mahruqi, Gaitha; Al Fakhri, Salma; Zafarulla, Roshna; Pathare, Anil V

    2016-01-01

    In Oman, the prevalence of health care associated methicillin resistant Staphylococcus aureus [HA-MRSA] is unknown. Therefore, to estimate the prevalence of HA-MRSA, we collected nasal swabs and swabs from cell phones on sterile polyester swabs and immediately inoculated on the mannitol salt agar containing oxacillin from medical students and hospital health care providers. Antibiotic susceptibility testing of the isolates was then performed using the Kirby Bauer's disc diffusion method. Additionally, a brief survey questionnaire was used to acquire demographic data. Amongst the 311 participants enrolled, nasal colonization with HA-MRSA was found in 47 individuals (15.1%, 95% confidence interval [CI]=11.1%, 19.1%). HA-MRSA was also isolated from the cell phone surfaces in 28 participants (9.0%, 95% CI=8.6%, 9.3%). 5 participants (1.6%) showed positive results both from their nasal swabs and from their cell phones. Antibiotic resistance to erythromycin [48%] and clindamycin [29%] was relatively high. 9.3% HA-MRSA isolates were vancomycin resistant [6.6% nasal carriage]. There was no statistically significant correlation between HA-MRSA isolates and the demographic characteristics or the risk factors namely gender, underlying co-morbidities like diabetes, hypertension, skin/soft tissue infections, skin ulcers/wounds, recent exposure to antibiotics, or hospital visits (p>0.05, Chi-square test). PMID:26768668

  2. The mechanism of antimicrobial activity of sophoraflavanone B against methicillin-resistant Staphylococcus aureus.

    Mun, Su-Hyun; Joung, Dae-Ki; Kim, Sung-Bae; Park, Sung-Joo; Seo, Yun-Soo; Gong, Ryong; Choi, Jang-Gi; Shin, Dong-Won; Rho, Jung-Rae; Kang, Ok-Hwa; Kwon, Dong-Yeul

    2014-03-01

    Sophoraflavanone B (SPF-B), a prenylated flavonoid, can be isolated from the roots of Desmodium caudatum. The aim of this study was to determine the mechanism of SPF-B's antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA). MRSA is a multidrug-resistant pathogen and the main cause of hospital- and community-acquired infections. The minimum inhibitory concentration (MIC) of SPF-B was assessed using the broth microdilution method. The mechanism of action of SPF-B on S. aureus was analyzed in combination assays incorporating detergents, ATPase inhibitors, and peptidoglycan (PGN) derived from S. aureus. Furthermore, morphological changes in the SPF-B-treated MRSA strains were investigated using transmission electron microscopy. The MIC of SPF-B for MRSA was in the range of 15.6-31.25 μg/mL. The mechanism of action of SPF-B on MRSA was investigated using combination assays with detergent and ATPase inhibitors. The optical density at 600 nm of MRSA suspensions treated with a combination of detergent and SPF-B reduced the MRSA by 63%-73%. In the SPF-B and PGN combination assay, direct binding of SPF-B with PGN from S. aureus was evident. These data may be validated for the development of new antibacterial drugs for low MRSA resistance. PMID:24601672

  3. Staphylococcus species and their Methicillin-Resistance in 7424 Blood Cultures for Suspected Bloodstream Infections

    Ariana ALMAŞ

    2011-06-01

    Full Text Available Objectives: The aim of this study was to evaluate the distribution of Staphylococcus species in bloodstream infections and to assess their susceptibility to methicillin. Material and Methods: Between January 1st 2008 - December 31st 2010, 7424 blood culture sets were submitted to the Laboratory Department of the Hospital for Clinical Infectious Diseases in Cluj-Napoca, Romania. The blood cultures were performed using BacT/Alert until January 2010 and BacT/Alert 3D automated system (bioMérieux after that date. The blood culture bottles were incubated at 37°C in a continuously monitoring system for up to 7 days. The strain identifications were performed by conventional methods, ApiStaph galleries and Vitek 2 Compact system. Susceptibility to methicillin was determined by disk diffusion method with cefoxitin disk and by using Vitek 2 Compact system. Results: From the total number of performed blood cultures, 568 were positive with Staphylococcus species. From 168 bacteriemic episodes 103 were with Staphylococcus aureus. Among 65 coagulase-negative staphylococci isolates, Staphylococcus epidermidis was the most frequently isolated species (34, followed by Staphylococcus hominis (15, Staphylococcus haemolyticus (8, Staphylococcus saprophyticus (3, Staphylococcus cohnii (1, Staphylococcus auricularis (1, and 3 strains that were not identified at species level. Methicillin resistance was encountered in 53.40% of Staphylococcus aureus strains and in 80% of coagulase-negative staphylococci. Conclusions: An important percentage of blood cultures were contaminated with Staphylococcus species. The main species identified in true bacteriemia cases were Staphylococcus aureus and Staphylococcus epidermidis. The percentage of methicillin-resistance, proved to be high not only for coagulase-negative staphylococci but also for Staphylococcus aureus.

  4. [Methicillin-resistant Staphylococcus aureus (MRSA) in veterinary medicine: a "new emerging pathogen"?].

    Walther, Birgit; Friedrich, Alexander W; Brunnberg, Leo; Wieler, Lothar H; Lübke-Becker, Antina

    2006-01-01

    The problem of nosocomial infections is of increasing importance in veterinary medicine. As an example, this review summarizes current knowledge regarding methicillin-resistant Staphylococcus aureus (MRSA) as a typical example, as these pathogens are the most important agents of nosocomial infections in human medicine worldwide and are being increasingly reported in veterinary medicine. MRSA are classified by their ability to be resistant against oxacillin/methicillin, this feature being confered by mecA, a gene which was acquired by horizontal gene transfer of the staphylococcal gene cassette (SCCmec). It is this genetic information that enables MRSA to be resistant against all penicillins, cehalosporins and carbapenems. In addition, MRSA are often resistant against a variety of other antiinfectives, i.e. aminoglycosides, macrolides, lincosamide, streptomycins, tetracyclin, chloramphenicol, but also against fluorquinolones and rifampicin. Presumably, these highly adapted strains are particularly able to acquire resistance genes located on plasmids or transposons. They are also able to develop point mutations, further leading to resistant phenotypes. If these pathogens are leading to infectious diseases, veterinarians may be confronted with a worst-case scenario, being left without any antiinfective therapeutic. As Staphylococcus aureus is highly tenacid, professional hygiene management is of utmost importance. The increasing number of published sporadic MRSA infections, MRSA-infectious diseases as well as MRSA outbreaks in veterinary medicine justifies their recognition as a "New Emerging Pathogen". So far, horses and dogs are mostly affected by MRSA. Although transmission between humans and animals has been reported occasionally, the sources, routes of transmission or the epidemiological relevance of MRSA infections in animals are far from being understood. Therefore, epidemiological investigations utilizing molecular typing tools are mandatory. Typing tools like

  5. Laboratory evaluation of phenotypic detection methods of methicillin-resistant Staphylococcus aureus

    Arunava Kali

    2014-12-01

    Full Text Available Although conventional antibiotic susceptibility tests are most commonly performed for methicillin-resistant Staphylococcus aureus (MRSA, the results of these phenotypic tests are dependent on the standardization of the culture conditions. The aim of the study was to evaluate the conventional phenotypic screening tests in comparison to the mecA gene polymerase chain reaction (PCR. One hundred and two clinical isolates of MRSA identified by the oxacillin disk diffusion were subjected to PCR for the mecA gene and by the cefoxitin disk diffusion test and culture on oxacillin screen agar, mannitol salt agar, and methicillin-resistant Staphylococcus aureus Agar (MeReSA selective medium, for MRSA. Although all 102 isolates were resistant in oxacillin and cefoxitin disk diffusion, 92 (90.1% isolates were positive for the mecA gene. The sensitivities of the mannitol salt agar, MeReSA agar, and oxacillin screen agar were 89.13, 97.82, and 98.91%, respectively. The oxacillin screen agar may be recommended for confirming methicillin resistance in the disk diffusion test in resource-poor settings, where molecular methods are not available.

  6. Antimicrobial susceptibility of Staphylococcus aureus and characterization of methicillin-resistant Staphylococcus aureus isolated from bovine mastitis in Korea.

    Nam, Hyang-Mi; Lee, Ae-Li; Jung, Suk-Chan; Kim, Mal-Nam; Jang, Geum-Chan; Wee, Sung-Hwan; Lim, Suk-Kyung

    2011-02-01

    A total of 402 Staphylococcus aureus isolates from bovine mastitis milk collected during 2003-2009 in Korea were tested for susceptibility to 20 antimicrobial agents. All S. aureus isolates were susceptible to 11 of 20 antimicrobials tested; no resistance was observed against pirlimycin, telithromycin, novobiocin, penicillin/novobiocin, quinupristin/dalfopristin, clindamycin, rifampin, ciprofloxacin, trimethprim/sulfamethoxazol, vancomycin, and linezolid. Over 66% of the S. aureus isolates were resistant to penicillin. Resistance was also seen for gentamicin (11.9%), erythromycin (7.7%), methicillin (oxacillin and cefoxitin, 6.2%), and tetracycline (4.2%). No noticeable change was observed in penicillin, gentamicin, and erythromycin resistance over the 7-year period. Tetracycline resistance appeared to decrease consistently, whereas methicillin resistance was observed from 2005. About 2.7% (11/402) were resistant to three or more antimicrobials. Genotyping of the 17 methicillin-resistant S. aureus (MRSA) isolated from each cow revealed two staphylococcal cassette chromosome mec (SCCmec) types (IV and IVa), three spa types (t286, t324, and untypable), and two sequence types (ST1 and ST72). Eleven of 17 (64.7%) MRSA strains belonged to SCCmec IVa-t324-ST72. The rest of strains belonged to SCCmec IVa-t286-ST1 (n = 3) and SCCmec IV-untypable-ST72 (n = 3). None of the MRSA carried the Panton-Valentine leukocidin gene. These characteristics are the same as those found in community-acquired (CA) MRSA strains prevalent in humans in Korea. Three pulsed-field gel electrophoresis types (A-C) were observed among the 17 MRSA strains examined, and 14 strains belonged to the same pulsed-field gel electrophoresis pattern regardless of their geographical origin and year of isolation. The results of this study provide evidence of CA-MRSA infection in dairy cattle for the first time in Korea. PMID:21034263

  7. Treating Central Catheter-Associated Bacteremia Due to Methicillin-Resistant Staphylococcus aureus: Beyond Vancomycin.

    Holt, Shannon; Thompson-Brazill, Kelly A; Sparks, E Ryan; Lipetzky, Juliana

    2016-08-01

    Methicillin-resistant Staphylococcus aureus is a frequent cause of hospital-associated infections, including central catheter-associated bacteremia. Vancomycin has been the drug of choice for treating this type of bacteremia for decades in patients who have no contraindications to the antibiotic. However, resistance to vancomycin is an emerging problem. Newer antibiotics approved by the Food and Drug Administration have activity against methicillin-resistant S aureus Some of the antibiotics also have activity against strains of S aureus that are intermediately susceptible or resistant to vancomycin. This article uses a case study to highlight the clinical signs of vancomycin failure and describes the indications for and appropriate use of alternative antimicrobials such as ceftaroline, daptomycin, linezolid, tigecycline, and telavancin. (Critical Care Nurse 2016;36[4]:46-57). PMID:27481801

  8. A laboratory study of susceptibility of methicillin resistant staphylococcus aureus (MRSA)

    Objective: To study the mode of infection, incidence of methicillin resistant staphylococcus aureus (MRSA) and their susceptibility against glycopeptides and fucidic acid, so that awareness may be created for consultants against such notorious rapidly spreading bacteria and recommendation can be made for their prevention and control. Methods: The specimens from various infections suspected on clinical ground were processed by standard methods and antibiotic susceptibility testing of all the 350 S. aureus and 135 MRSA isolates was done by using modified Kirby Bauer Disc diffusion technique. Results: Of 350 positive S.aureus cultures, 135 were found to be Methicillin resistant (38.5%) which showed susceptibility 96%, 94% and 86% to Vancomycin, Teicoplanin and Fucidic acid respectively. Conclusion: This study showed a high incidence of MRSA at Mayo Hospital Lahore, Glycopeptides and Fucidic acid were found to be valuable antibiotics against MRSA. (author)

  9. Colonization of butchers with livestock-associated methicillin-resistant Staphylococcus aureus

    Boost, Maureen; Ho, J.; Guardabassi, Luca;

    2013-01-01

    Reports have documented colonization of swine in Europe, North America and more recently in China with livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA). Contamination of pig farmers, veterinarians and abattoir workers with these strains has been observed. However, although...... collected from 300 pork butchers at markets throughout Hong Kong were enriched in brain heart infusion broth with 5% salt and cultured on MRSASelect(®) . Isolates were confirmed as Staphylococcus aureus and susceptibility testing performed. The presence of mecA was confirmed, SCCmec and spa type determined...

  10. Rapid Increase of Genetically Diverse Methicillin-Resistant Staphylococcus aureus, Copenhagen, Denmark

    Bartels, Mette Damkjær; Boye, Kit; Larsen, Anders Rhod;

    2007-01-01

    In Copenhagen, methicillin-resistant Staphylococcus aureus (MRSA) accounted for <15 isolates per year during 1980-2002. However, since 2003 an epidemic increase has been observed, with 33 MRSA cases in 2003 and 110 in 2004. We analyzed these 143 cases epidemiologically and characterized isolates by...... pulsed-field gel electrophoresis, Staphylococcus protein A (spa) typing, multilocus sequence typing, staphylococcal chromosome cassette (SCC) mec typing, and detection of Panton-Valentine leukocidin (PVL) genes. Seventy-one percent of cases were community-onset MRSA (CO-MRSA); of these, 36% had no...

  11. Rapid detection of methicillin-resistant Staphylococcus aureus directly from clinical samples: methods, effectiveness and cost considerations

    Stürenburg, E

    2009-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) isolates is a serious public health problem whose ever-increasing rate is commensurate with the pressure it is exerting on the healthcare system. At present, more than 20% of clinical S. aureus isolates in German hospitals are methicillin resistant. Strategies from low-prevalence countries show that this development is not necessarily inevitable. In the Scandinavian countries and the Netherlands, thanks to a rigorous prevention programme, M...

  12. Rapid detection of methicillin-resistant Staphylococcus aureus directly from clinical samples: methods, effectiveness and cost considerations

    Stürenburg, Enno

    2009-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) isolates is a serious public health problem whose ever-increasing rate is commensurate with the pressure it is exerting on the healthcare system. At present, more than 20% of clinical S. aureus isolates in German hospitals are methicillin resistant. Strategies from low-prevalence countries show that this development is not necessarily inevitable. In the Scandinavian countries and the Netherlands, thanks to a rigorous prevention programme, MRS...

  13. Prophylactic Effect of Vancomycin on Infection after Cranioplasty in Methicillin-Resistant Staphylococcus Aureus Carriers with Traumatic Brain Injury

    Bang, Jin Hyuk; Cho, Keun-Tae; Park, Seong Yeon

    2015-01-01

    Objective Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase negative staphylococci (MRCNS) are major causes of neurosurgical infection. Nasal colonization of MRSA is the most important risk factor and MRSA screening can be a screening method to identify MRSA and MRCNS colonization. We retrospectively evaluated prophylactic effect of vancomycin on MRSA or MRCNS surgical site infection (SSI) after cranioplasty following decompressive craniectomy (DC) after t...

  14. Rapid Detection of Methicillin Resistance in Staphylococcus aureus Isolates by the MRSA-Screen Latex Agglutination Test

    van Leeuwen, Willem; Pelt, Cindy; Luijendijk, Ad; Verbrugh, Henri; Goessens, Wil

    1999-01-01

    textabstractThe slide agglutination test MRSA-Screen (Denka Seiken Co., Niigata, Japan) was compared with the mecA PCR ("gold standard") for the detection of methicillin resistance in Staphylococcus aureus. The MRSA-Screen test detected the penicillin-binding protein 2a (PBP2a) antigen in 87 of 90 genetically diverse methicillin-resistant S. aureus (MRSA) stock culture strains, leading to a sensitivity of 97%. The three discrepant MRSA strains displayed positive results only after induction o...

  15. Frequency and Treatment of Methicillin Resistant Staphylococcus aureus in Obstetric and Gynaecological Sepsis

    Objective: To perform culture and sensitivity for pathogens causing puerperal and postoperative wound sepsis and determine the frequency of Methicillin Resistant Staphylococcus aureus (MRSA) in such infections. Study Design: Observational study. Place and Duration of Study: Obstetrics and Gynaecology Ward, Jinnah Postgraduate Medical Centre, Karachi, from December 2008 to May 2010. Methodology: All patients presenting with puerperal sepsis or postoperative wound infection were enrolled. Pus was collected for culture and sensitivity using standard technique. Two samples were taken from each patient; one before starting the treatment and one at the end of treatment. Ames transport medium was used. Empirical treatment with triple regimen (Ampicillin, Metronidazole and Gentamicin) was started immediately to cover Gram positive as well as negative bacteria in addition to anaerobic infection. After receiving the sensitivity report, antimicrobial agent were changed accordingly. Samples from ward and theater staff and environment were also taken to look for possible mode of transmission. Data was recorded on a proforma. Discrete variables are expressed as percentages. Results: Staphylococcus aureus was the most frequent organism isolated in 34.6% cases. Methicillin sensitive Staphylococcus aureus was seen in 20% cases and methicillin resistant Staphylococcus aureus was seen in 14.6%. Out of these 14.6% MRSA, (17) 77% was associated with puerperal sepsis and rest (5) 23% was associated with postoperative wound infection. It showed best sensitivity to vancomycin. Conclusion: Staphylococcus aureus and E. coli were common causative agent of postoperative infections and puerperal sepsis. (author)

  16. Genetic behavior of the methicillin resistance determinant in Staphylococcus aureus.

    Stewart, G C; Rosenblum, E D

    1980-01-01

    The cotransformation frequency of mecC5 with pur-102 using Staphylococcus aureus C5 deoxyribonucleic acid was found to be approximately 45%. However, in cotransduction studies, there was a 15% cotransduction of purine prototrophy and methicillin sensitivity but, in the reciprocal cross, no purine-prototrophic plus Mecr cotransductants were obtained (frequency less than 0.06%). The data support the hypothesis that the mec determinant resides on an inserted deoxyribonucleic acid sequence in S. ...

  17. Diversity of Staphylococcal Cassette Chromosome mec Elements in Predominant Methicillin-Resistant Staphylococcus aureus Clones in a Small Geographic Area ▿

    Basset, Patrick; Senn, Laurence; Vogel, Valérie; Zanetti, Giorgio; Blanc, Dominique S.

    2010-01-01

    Recent population genetic studies suggest that staphylococcal cassette chromosome mec (SCCmec) was acquired much more frequently than previously thought. In the present study, we aimed to investigate the diversity of SCCmec elements in a local methicillin-resistant Staphylococcus aureus (MRSA) population. Each MRSA isolate (one per patient) recovered in the Vaud canton of Switzerland from January 2005 to December 2008 was analyzed by the double-locus sequence typing (DLST) method and SCCmec t...

  18. Antimicrobial activity of PVP from an Antarctic bacterium, Janthinobacterium sp. Ant5-2, on multi-drug and methicillin resistant Staphylococcus aureus

    Huang, Jonathan P.; Mojib, Nazia; Goli, Rakesh R.; Watkins, Samantha; Ken B Waites; Ravindra, Rasik; Andersen, Dale T.; Bej, Asim K.

    2012-01-01

    Multiple drug resistant (MDR) and methicillin-resistant Staphylococcus aureus (MRSA) have become increasingly prevalent as a community acquired infection. As a result limited treatment options are available with conventional synthetic antibiotics. Bioprospecting natural products with potent antimicrobial activity show promise for developing new drugs against this pathogen. In this study, we have investigated the antimicrobial activity of a purple violet pigment (PVP) from an Antarctic bacteri...

  19. Comparison of multi-drug resistant environmental methicillin-resistant Staphylococcus aureus [MRSA] isolated from recreational beaches and high touch surfaces in built environments

    MarilynCRoberts; OlusegunOSoge

    2013-01-01

    Over the last decade community-acquired methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major cause of disease in the general population with no health care exposure or known classical risk factors for MRSA infections. The potential community reservoirs have not been well defined though certain strains such as ST398 and USA300 have been well studied in some settings. MRSA has been isolated from recreational beaches, high-touch surfaces in homes, universities, and other com...

  20. Impact of Vancomycin on sarA-Mediated Biofilm Formation: Role in Persistent Endovascular Infections Due to Methicillin-Resistant Staphylococcus aureus

    Abdelhady, W; Bayer, A S; Seidl, K; Moormeier, D E; Bayles, K W; Cheung, A.; Yeaman, M R; Xiong, Y Q

    2014-01-01

    Background. Staphylococcus aureus is the most common cause of endovascular infections. The staphylococcal accessory regulator A locus (sarA) is a major virulence determinant that may potentially impact methicillin-resistant S. aureus (MRSA) persistence in such infections via its influence on biofilm formation. Methods. Two healthcare-associated MRSA isolates from patients with persistent bacteremia and 2 prototypical community-acquired MRSA strains, as well as their respective isogenic sar...

  1. Current Concepts in Antimicrobial Therapy Against Select Gram-Positive Organisms: Methicillin-Resistant Staphylococcus aureus, Penicillin-Resistant Pneumococci, and Vancomycin-Resistant Enterococci

    Rivera, Ana Maria; Boucher, Helen W.

    2011-01-01

    Gram-positive bacteria cause a broad spectrum of disease in immunocompetent and immunocompromised hosts. Despite increasing knowledge about resistance transmission patterns and new antibiotics, these organisms continue to cause significant morbidity and mortality, especially in the health care setting. Methicillin-resistant Staphylococcus aureus poses major problems worldwide as a cause of nosocomial infection and has emerged as a cause of community-acquired infections. This change in epidemi...

  2. Molecular Studies on Methicillin-Resistant Staphylococcus aureus

    The present study of the MecA gene in our clinical isolates has been detected and verified by antibiotic disc diffusion test and nested Polymerase Chain Reaction (PCR). Part of the product of the second PCR was also sequenced. The results indicated 97.7% similarity between the sequences of the mecA gene isolated from an Egyptian Staphylococcus aureus strain and that compared from Staphylococcus aureus strain no. GI46628 cited at the European Molecular Biology Laboratory (EMBL) database under accession number Y00688 in the region from nucleotide 467 to 875. The effect of gamma-radiation on these isolates was observed by plotting the dose survival curves of these isolates and determining their D10 values. Their D10 values were found to be ranged from 0.44 to 0.66 kGy. Antibiotic sensitivity tests were also carried out after exposure of Oxacillin-susceptible isolate to sub -lethal doses of γ-radiation.Results indicated that Staphylococcus aureus isolates which were sensitive to oxacillin discs were found by PCR to harbor the mecA gene in their genomes. Also, exposure of a sensitive isolate to sublethal doses of gamma radiation led to the emergence of a oxacillin-resistant variant which could be a serious problem in case of using sub-lethal doses of radiation for the sterilization of medical products

  3. Missense mutations in PBP2A Affecting ceftaroline susceptibility detected in epidemic hospital-acquired methicillin-resistant Staphylococcus aureus clonotypes ST228 and ST247 in Western Switzerland archived since 1998.

    Kelley, William L; Jousselin, Ambre; Barras, Christine; Lelong, Emmanuelle; Renzoni, Adriana

    2015-04-01

    The development and maintenance of an arsenal of antibiotics is a major health care challenge. Ceftaroline is a new cephalosporin with activity against methicillin-resistant Staphylococcus aureus (MRSA); however, no reports concerning MRSA ceftaroline susceptibility have been reported in Switzerland. We tested the in vitro activity of ceftaroline against an archived set of 60 MRSA strains from the University Hospital of Geneva collected from 1994 to 2003. Our results surprisingly revealed ceftaroline-resistant strains (MIC, >1 μg/ml in 40/60 strains; EUCAST breakpoints, susceptible [S], ≤1 μg/ml; resistant [R], >1 μg/ml) were present from 1998 to 2003. The detected resistant strains predominantly belonged to sequence type 228 (ST228) (South German clonotype) but also to ST247 (Iberian clonotype). A sequence analysis of these strains revealed missense mutations in the penicillin-binding protein 2A (PBP2A) allosteric domain (N146K or E239K and N146K-E150K-G246E). The majority of our ST228 PBP2A mutations (N146K or E150K) were distinct from ST228 PBP2A allosteric domain mutations (primarily E239K) recently described for MRSA strains collected in Thailand and Spain during the 2010 Assessing Worldwide Antimicrobial Resistance Evaluation (AWARE) global surveillance program. We also found that similar allosteric domain PBP2A mutations (N146K) correlated with ceftaroline resistance in an independent external ST228 MRSA set obtained from the nearby University Hospital of Lausanne, Lausanne, Switzerland, collected from 2003 to 2008. Thus, ceftaroline resistance was observed in our archived strains (including two examples of an MIC of 4 µg/ml for the Iberian ST247 clonotype with the triple mutation N146K/E150K/G246E), at least as far back as 1998, considerably predating the commercial introduction of ceftaroline. Our results reinforce the notion that unknown parameters can potentially exert selective pressure on PBP2A that can subsequently modulate ceftaroline

  4. PCR-based identification of methicillin-resistant Staphylococcus aureus strains and their antibiotic resistance profiles

    Abazar Pournajaf; Abdollah Ardebili; Leyla Goudarzi; Mahmoud Khodabandeh; Tahmineh Narimani; Hassan Abbaszadeh

    2014-01-01

    Objective: To evaluated the PCR for mecA gene compared with the conventional oxacillin disk diffusion method for methicillin-resistant Staphylococcus aureus (S. aureus) identification. Methods: A total of 292 S. aureus strains were isolated from various clinical specimens obtained from hospitalized patients. Susceptibility test to several antimicrobial agents was performed by disk diffusion agar according to Clinical and Laboratory Standards Institute guidelines. The PCR amplification of the mecA gene was carried out in all the clinical isolates.Results:activity and vancomycin was the most effective. The rate of methicillin-resistant S. aureus prevalence determined by oxacillin disk diffusion method was 47.6%; whereas, 45.1% of S. aureus isolates were mecA- positive in the PCR assay. Among antibiotics used in our study, penicillin showed the least anti-staphylococcal Conclusions: This study is suggestive that the PCR for detection of mecA gene is a fast, accurate and valuable diagnostic tool, particularly in hospitals in areas where methicillin-resistant S. aureus is endemic.

  5. Key genetic elements and regulation systems in methicillin-resistant Staphylococcus aureus.

    Hao, Haihong; Dai, Menghong; Wang, Yulian; Huang, Lingli; Yuan, Zonghui

    2012-11-01

    Methicillin-resistant Staphylococcus aureus (MRSA), popularly known as a type of superbug, has been a serious challenge for animal and human health. S. aureus has developed methicillin resistance mainly by expression of β-lactamase and PBP2a, which is regulated by the blaZ-blaI-blaR1 and mecA-mecI-mecRI systems. Other genetic elements, including murE and femA, also participate in expression of methicillin resistance, but the mechanism remains unclear. The evolution of the staphylococcal cassette chromosome mec determines the epidemiological risk of MRSA. The plasmid-located gene cfr might contribute to multiresistance and transmission of MRSA. Some virulence factors, including Panton-Valentine leukocidin, phenol-soluble modulin, arginine catabolic mobile element and other toxin elements enhance the pathogenesis and fitness of MRSA. Two-component regulation systems (agr, saeRS and vraRS) are closely associated with pathogenesis and drug resistance of MRSA. The systematic exploration of key genetic elements and regulation systems involved in multidrug resistance/pathogenesis/transmission of MRSA is conclusively integrated into this review, providing fundamental information for the development of new antimicrobial agents and the establishment of reasonable antibiotic stewardship to reduce the risk of this superbug. PMID:23075449

  6. Prospective Analysis Methicillin-resistant Staphylococcus aureus and its Risk Factors

    Abdallah, Soad A; Al-Asfoor, Khulood K; Salama, Mona F; Al-Awadi, Bashayer M

    2013-01-01

    Background: Since the early nineties, a new methicillin-resistant Staphylococcus aureus (MRSA) has existed in a form correlating with community health personnel. Community-acquired MRSA (CA-MRSA) could be differentiated from healthcare-associated MRSA (HA-MRSA) microbiologically, epidemiologically, and molecularly. Aims: To determine the prevalence, risk factors of MRSA infections in community and hospital. Settings: The incidence and risk factors for CA-MRSA and HA-MRSA among patients of medical, surgical, and pediatrics wards and ICU at a Kuwaiti teaching hospital between 1 March 2011 and 30 November 2011 were studied. Materials and Methods: Cultures for MRSA were taken from nasal (nostril), groin, axilla, wound, sputum, or throat, and the inguinal area in all enrolled patients upon admission. All preserved isolates were examined for their susceptibility to different types of antibiotics. Results and Conclusion: A total of 71 MRSA patients admitted to different hospital wards were examined. Among these patients, 52 (73.2%) were carriers of MRSA before they were admitted to the hospital. Nineteen patients (26.8%) were found to have acquired MRSA during their stay in the hospital. Twenty-nine patients (40.8%) were given mupirocin local skin antibiotic. Binomial and the t-test (paired) were used to compare the prevalence of CA-MRSA and HA-MRSA; significant correlation (P < 0.05) between the type of MRSA and different wards, sites, and lengths of hospital stay was found. The level of serum albumin that is routinely measured at hospital admission is a predictor to MRSA infection. This study suggests that S. aureus and MRSA should become a national priority for disease control to avoid outbreaks. PMID:23599613

  7. Use of oligoarrays for characterization of community-onset methicillin-resistant Staphylococcus aureus.

    Koessler, Thibaud; Francois, Patrice; Charbonnier, Yvan; Huyghe, Antoine; Bento, Manuela; Dharan, Sasi; Renzi, Gesuele; Lew, Daniel; Harbarth, Stephan; Pittet, Didier; Schrenzel, Jacques

    2006-03-01

    Until recently, methicillin-resistant Staphylococcus aureus (MRSA) was considered the prototype of a hospital-acquired bacterial pathogen. However, recent reports have shown that MRSA has now emerged in the community. Characterization of specific markers for distinguishing the origin of isolates could contribute to improved knowledge of MRSA epidemiology. The release of whole-genome sequences of hospital- and community-acquired S. aureus strains allowed the development of whole-genome content analysis techniques, including microarrays. We developed a microarray composed of 8,191 open reading frame-specific oligonucleotides covering >99% of the four sequenced S. aureus genomes (N315, Mu50, MW2, and COL) to evaluate gene contents of hospital- and community-onset S. aureus strains. In parallel, pulsed-field gel electrophoresis, variable number of tandem repeats, antibiogram, staphylococcal cassette chromosome-mec element typing, and presence of the Panton-Valentine leukocidin gene were evaluated in a collection of 15 clinical isolates. Clusters obtained with microarrays showed a high degree of similarity with those obtained by pulsed-field gel electrophoresis or variable number of tandem repeats. Clusters clearly segregated hospital-onset strains from community-onset strains. Moreover, the microarray approach allowed definition of novel marker genes and chromosomal regions specific for given groups of isolates, thus providing better discrimination and additional information compared to pulsed-field gel electrophoresis and variable number of tandem repeats. Finally, the comparative genome hybridization approach unraveled the occurrence of multiple horizontal transfer events leading to community-onset MRSA as well as the need for a specific genetic background in recipient strains for both the acquisition and the stability of the mec element. PMID:16517892

  8. Use of Oligoarrays for Characterization of Community-Onset Methicillin-Resistant Staphylococcus aureus

    Koessler, Thibaud; Francois, Patrice; Charbonnier, Yvan; Huyghe, Antoine; Bento, Manuela; Dharan, Sasi; Renzi, Gesuele; Lew, Daniel; Harbarth, Stephan; Pittet, Didier; Schrenzel, Jacques

    2006-01-01

    Until recently, methicillin-resistant Staphylococcus aureus (MRSA) was considered the prototype of a hospital-acquired bacterial pathogen. However, recent reports have shown that MRSA has now emerged in the community. Characterization of specific markers for distinguishing the origin of isolates could contribute to improved knowledge of MRSA epidemiology. The release of whole-genome sequences of hospital- and community-acquired S. aureus strains allowed the development of whole-genome content analysis techniques, including microarrays. We developed a microarray composed of 8,191 open reading frame-specific oligonucleotides covering >99% of the four sequenced S. aureus genomes (N315, Mu50, MW2, and COL) to evaluate gene contents of hospital- and community-onset S. aureus strains. In parallel, pulsed-field gel electrophoresis, variable number of tandem repeats, antibiogram, staphylococcal cassette chromosome-mec element typing, and presence of the Panton-Valentine leukocidin gene were evaluated in a collection of 15 clinical isolates. Clusters obtained with microarrays showed a high degree of similarity with those obtained by pulsed-field gel electrophoresis or variable number of tandem repeats. Clusters clearly segregated hospital-onset strains from community-onset strains. Moreover, the microarray approach allowed definition of novel marker genes and chromosomal regions specific for given groups of isolates, thus providing better discrimination and additional information compared to pulsed-field gel electrophoresis and variable number of tandem repeats. Finally, the comparative genome hybridization approach unraveled the occurrence of multiple horizontal transfer events leading to community-onset MRSA as well as the need for a specific genetic background in recipient strains for both the acquisition and the stability of the mec element. PMID:16517892

  9. Characterization of methicillin-resistant Staphylococcus aureus Sequence Type 398

    Christiansen, Mette Theilgaard

    Staphylococcus aureus is an opportunistic pathogen that colonizes the nares and skin surfaces of several animal species, including man. S. aureus can cause a wide variety of infections ranging from superficial soft tissue and skin infections to severe and deadly systemic infections. Traditionally S...... for LA-MRSA ST398 survival on porcine skin and nasal epithelium ex vivo were identified. These genes could represent targets for de-colonization, which could help prevent further spread and adaption of LA-MRSA ST398. Manuscript III describes the construction of the S. aureus VirulenceFinder database....... The database can be applied for identification of virulence genes in S. aureus using whole genome 5 sequence data. The S. aureus VirulenceFinder will be part of the tool package generated for the Centre for Genomic Epidemiology (CGE) (www.genomicepidemiology.org)....

  10. Antibacterial activity of mupirocin (pseudomonic Acid A) against, clinical isolates of methicillin-resistant staphylococcus aureus

    Colonized patients and health care workers are the main source of spread of methicillin resistant Staphylococcus aureus (MRSA) in hospitals. The elimination of nasal colonized MRSA plays a crucial role in infection control protocols. Mupirocin (pseudomonic acid A) is used for eradication of MRSA nasal carriage. Increasing use of pseudomonic acid A (mupirocin) has led to emergence of resistance. Objective To determine low and high level resistance of MRSA isolates from clinical specimens against mupirocin. Place and duration of study: Study was conducted at Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi from July 2006 to June 2007. Material and methods Three hundred methicillin-resistant Staphylococcus aureus isolates were studied. All clinical specimens were processed for culture and sensitivity. Staphylococcus aureus isolates were tested for methicillin resistance using 1 micro g oxacillin disk. The isolates were further tested by PCR for the presence of mecA gene. Minimum Inhibitory Concentration (MIC) of mupirocin against MRSA isolates was determined using agar dilution technique. Results Out of 300 MRSA isolates, 98% were found to have MlC against mupirocin as smaller than 4 micro g/mL. Remaining 2% isolates revealed low level resistance (MIC greater than 8 micro g/mL to 256 micro g/mL), no high level resistance (MIC greater than 512 micro g/mL) against mupirocin was detected. Conclusions: High level mupirocin resistance has not emerged so far in our setup. Due to increasing use of mupirocin, emergence of resistance against mupirocin among MRSA is a strong possibility. Strategy encompassing rational use of antimicrobials, hospital infection control, surveillance for the detection of mupirocin resistance and judicious use of this agent is required. (author)

  11. Fatal myocardial microabscesses caused by methicillin-resistant Staphylococcus aureus in a burn patient

    Hsiang-Wei Huang

    2014-03-01

    Full Text Available Bacteremia- or sepsis-associated myocardial abscess is often an incidental postmortem diagnosis in patients who die of overwhelming septicemia. Myocardial abscess is more rarely the immediate cause of death as a consequence of abscess rupture or the cause of arrhythmia. We report a 66-year-old female who succumbed to sudden cardiac death with a hemodynamically stable methicillin-resistant Staphylococcus aureus (MRSA bacteremia, while in recovery after an accidental thermal burn. Autopsy revealed extensive myocardial abscesses and an abscess in the pineal gland. Myocardial microabscesses should be considered a rare cause of sudden cardiac death in patients with hemodynamically stable MRSA bacteremia.

  12. Zinc resistance of Staphylococcus aureus of animal origin is strongly associated with methicillin resistance

    Cavaco, Lina; Hasman, Henrik; Aarestrup, Frank Møller

    2011-01-01

    This study was conducted to determine the occurrence of zinc and copper resistances in methicillin-resistant Staphylococcus aureus (MRSA) from swine and veal calves in a global strain collection.The test population consisted of 476 porcine MRSA isolates from ten European countries, 18 porcine MRSA...... isolates from Canada and seven MRSA from China, 92 MRSA and 60 methicillin-susceptible S. aureus (MSSA) isolates from veal calves in the Netherlands and 88 porcine MSSA isolates from four European countries. Most porcine MRSA (n=454) and all bovine MRSA belonged to clonal complex (CC) 398 whereas 37...

  13. Typing of Methicillin-Resistant Staphylococcus aureus by Ribosome Spacer and Arbitrarily Primed Polymerase Chain Reaction

    Essawi, Tamer; Adwan, Kamel; ABU-HASSAN, Nael; ADWAN, Galeb; Saleh, Ahmed

    2004-01-01

    Thirty-five methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates were collected from 3 hospitals in the northern and southern parts of Palestine between February and May 1998. These isolates were typed by ribosome spacer PCR (RS-PCR) and arbitrarily primed PCR (AP-PCR). RS-PCR generated 9 different genotypes. The use of AP-PCR provided a high resolution typing method and allowed us to define 11 different clusters. Three major clusters, however, based on the combination of both...

  14. Alternatives to vancomycin for the treatment of methicillin-resistant Staphylococcus aureus infections.

    Micek, Scott T

    2007-09-15

    Vancomycin remains the reference standard for the treatment of systemic infection caused by methicillin-resistant Staphylococcus aureus (MRSA). However, as a result of limited tissue distribution, as well as the emergence of isolates with reduced susceptibility and in vitro resistance to vancomycin, the need for alternative therapies that target MRSA has become apparent. New treatment options for invasive MRSA infections include linezolid, daptomycin, tigecycline, and quinupristin/dalfopristin. Additionally, a number of new anti-MRSA compounds are in development, including novel glycopeptides (dalbavancin, telavancin, and oritavancin), ceftobiprole, and iclaprim. The present article will review clinical issues surrounding the newly marketed and investigational agents with activity against MRSA. PMID:17712745

  15. Origins and Evolution of Methicillin-Resistant Staphylococcus aureus Clonal Lineages

    Gomes, AR; Westh, Henrik; Lancastre, H de

    2006-01-01

    Most methicillin-resistant Staphylococcus aureus (MRSA) isolates identified among blood isolates collected in Denmark between 1957 and 1970 belonged to either phage group III or the closely related 83A complex and had a PSTM antibiotype (resistance to penicillin [P], streptomycin [S], tetracycline...... [T], and methicillin [M]). Recently, some of these isolates were shown to have the same genetic backgrounds as contemporary epidemic MRSA isolates, and Danish methicillin-susceptible S. aureus (MSSA) isolates from the 1960s with a PST antibiotype were proposed to have been the recipients of the mec...

  16. Sternal and costochondral infections with gentamicin and methicillin resistant Staphylococcus aureus following thoracic surgery.

    Cafferkey, M T; Luke, D A; Keane, C T

    1983-01-01

    Six patients in a thoracic unit developed sternal osteomyelitis and costochondritis following median sternotomy. Five of the patients were operated on in another hospital. Gentamicin and methicillin resistant Staphylococcus aureus was isolated in pure culture in each case. The S. aureus isolate from 2 patients was of the same phage type suggesting cross-infection. Antibiotic prophylaxis administered in the perioperative period was ineffective. One patient, treated with amikacin (to which all of the strains were sensitive in vitro) and cefuroxime, died from overwhelming infection in spite of débridement and resuturing of the wound. The remaining 5 patients were cured with vancomycin therapy usually coupled with surgical intervention. PMID:6557667

  17. Evaluation of Three Rapid Methods for Detection of Methicillin Resistance in Staphylococcus aureus

    Louie, L.; Matsumura, S. O.; Choi, E; Louie, M; Simor, A E

    2000-01-01

    The probe-based Velogene Rapid MRSA Identification Assay (ID Biomedical Corp., Vancouver, British Columbia, Canada) and the latex agglutination MRSA-Screen (Denka Seiken Co., Tokyo, Japan) were evaluated for their ability to identify methicillin-resistant Staphylococcus aureus (MRSA) and to distinguish strains of MRSA from borderline oxacillin-resistant S. aureus (BORSA; mecA-negative, oxacillin MICs of 2 to 8 μg/ml). The Velogene is a 90-min assay using a chimeric probe to detect the mecA ge...

  18. Misidentification of methicillin-resistant Staphylococcus aureus (MRSA in hospitals in Tripoli, Libya

    Mohamed O. Ahmed

    2010-11-01

    Full Text Available Background: Methicillin-resistant Staphylococcus aureus (MRSA is a nosocomial (hospital-acquired pathogen of exceptional concern. It is responsible for life-threatening infections in both the hospital and the community. Aims: To determine the frequency of MRSA misidentification in hospitals in Tripoli, Libya using current testing methods. Methods: One hundred and seventy S. aureus isolates previously identified as MRSA were obtained from three hospitals in Tripoli. All isolates were reidentified by culturing on mannitol salt agar, API 20 Staph System and retested for resistance to methicillin using the cefoxitin disk diffusion susceptibility test and PBP2a. D-tests and vancomycin E-tests (Van-E-tests were also performed for vancomycin-resistant isolates. Results: Of the 170 isolates examined, 86 (51% were confirmed as MRSA (i.e. 49% were misidentified as MRSA. Fifteen (17% of the confirmed MRSA strains exhibited inducible clindamycin resistance. Of the 86 confirmed MRSA isolates, 13 (15% were resistant to mupirocin, 53 (62% were resistant to ciprofloxacin, 41 (48% were resistant to trimethoprim-sulfamethoxazole, and none were resistant to linezolid. Although disc-diffusion testing indicated that 23 (27% of the isolates were resistant to vancomycin, none of the isolates were vancomycin-resistant by Van-E-test. Conclusions: Misidentification of nosocomial S. aureus as MRSA is a serious problem in Libyan hospitals. There is an urgent need for the proper training of microbiology laboratory technicians in standard antimicrobial susceptibility procedures and the implementation of quality control programs in microbiology laboratories of Libyan hospitals.

  19. Molecular characterization of methicillin-resistant Staphylococcus aureus recovered from outpatient clinics in Riyadh, Saudi Arabia

    To examine the recovered strains phenotypically, by conventional methods and genotypically by polymerase chain reaction (PCR), for direct detection of Staphylococcus aureus (S. aureus) 16S ribosomal Ribonucleic Acid (rRNA) gene (which serves as an internal control) and mecA gene. Secondly, introduce multiplex PCR targeting at the same time S. aureus 16S rRNA, Panton-Valentine Leucocidin (PVL), and staphylococcal cassette chromosome mec (SCCmec) type 4. Thirty-seven strains of S. aureus collected in 2007 from outpatient clinics in King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia, were tested in the College of Pharmacy phenotypically by conventional methods and genotypically by PCR for direct detection of S. aureus 16S rRNA and mecA genes. All the 37 strains, were tested also by multiplex PCR targeting at the same time S. aureus 16S rRNA, PVL, and (SCCmec) type 4. Polymerase chain reaction detected all the 37 bacteriologically positive S. aureus (100%) and the mecA gene in all strains phenotypically resistant to methicillin (100%), at the same time it detected the mecA gene in 2 strains phenotypically sensitive to methicillin. Only 3 strains (8.1%) recovered from skin and soft tissue infections were positive for PVL and SCCmec type 4. The PCR assay can be used for rapid detection of S. aureus and mecA gene. At the same time the multiplex PCR assay explained in this study is a rapid, sensitive, and reliable test for direct detection of community-acquired methicillin-resistant S. aureus. (author)

  20. Carriage of methicillin-resistant Staphylococcus aureus by wild urban Norway rats (Rattus norvegicus.

    Chelsea G Himsworth

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA is an important cause of multi-drug-resistant infections in people, particularly indigent populations. MRSA can be transmitted between people and domestic animals, but the potential for transmission between people and commensal pests, particularly rodents, had not been investigated. The objective of this study was to identify the presence and characterize the ecology of MRSA in rats (Rattus spp. from in an impoverished, inner-city neighborhood. Oropharyngeal swabs were collected from rats trapped in 33 city blocks and one location within the adjacent port. Bacterial culture was performed and MRSA isolates were characterized using a variety of methods, including whole-genome sequencing (WGS. The ecology of MRSA in rats was described using phylogenetic analysis, geospatial analysis, and generalized linear mixed models. MRSA was identified 22 of 637 (3.5% rats tested, although prevalence varied from 0 - 50% among blocks. Isolates belonged to 4 clusters according to WGS, with the largest cluster (n = 10 containing isolates that were genetically indistinguishable from community-acquired USA300 MRSA strains isolated from people within the study area. MRSA strains demonstrated both geographic clustering and dispersion. The odds of an individual rat carrying MRSA increased with increased body fat (OR = 2.53, 95% CI = 1.33-4.82, and in the winter (OR = 5.29, 95% CI = 1.04-26.85 and spring (OR = 5.50, 95% CI = 1.10-27.58 compared to the fall. The results show that urban rats carried the same MRSA lineages occurring in local human and/or animal populations, supporting recent transmission from external sources. MRSA carriage was influenced by season, most likely as a result of temporal variation in rat behavior and rat-human interactions.

  1. Infecciones adquiridas en la comunidad por Staphylococcus aureus resistente a meticilina en un hospital de agudos Community-acquired methicillin-resistant Staphylococcus aureus infections in a hospital for acute diseases

    S. Palombarani; Gardella, N.; A. Tuduri; S. Figueroa; G. Sly; R. Corazza; G. Gutkind; Almuzara, M.; Mollerach, M.

    2007-01-01

    Staphylococcus aureus resistente a meticilina (SAMR) es uno de los principales agentes asociados a infecciones intrahospitalarias; sin embargo, en los últimos años ha surgido como un patógeno emergente de la comunidad, causando infecciones graves, principalmente en jóvenes. Se describen 33 casos de infecciones por SAMR de origen comunitario, diagnosticadas entre mayo de 2005 y junio de 2006 en el HIGA "Eva Perón". Se estudiaron retrospectivamente los aislamientos; se confirmó la resistencia a...

  2. Quercus infectoria: a candidate for the control of methicillin-resistant Staphylococcus aureus infections.

    Chusri, S; Voravuthikunchai, S P

    2008-04-01

    Acetone, ethyl acetate, 95% ethanol and aqueous extracts of Quercus infectoria (Q. infectoria) demonstrated significant antibacterial activities against all strains of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible Staphylococcus aureus (MSSA). Inhibition zones were in the range 11.75-16.82 mm. Both MRSA and MSSA strains exhibited minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values at 0.13 and 0.13-1.00 mg/mL, respectively. At 2 MIC, the growth of two representative MRSA strains was continually inhibited for at least 20 h. Surviving MRSA cells were not detected within 12-14 h after treatment with the extract at 4 MIC concentration. Staphylococcus aureus ATCC 25923 demonstrated similar results. PMID:18338770

  3. A pentaplex PCR assay for the rapid detection of methicillin-resistant Staphylococcus aureus and Panton-Valentine Leucocidin

    Al-Talib Hassanain

    2009-05-01

    Full Text Available Abstract Background Staphylococcus aureus is a major human pathogen, especially methicillin-resistant S. aureus (MRSA, which causes a wide range of hospital and community-acquired infections worldwide. Conventional testing for detection of MRSA takes 2–5 days to yield complete information of the organism and its antibiotic sensitivity pattern. Results The present study focused on the development of a pentaplex PCR assay for the rapid detection of MRSA. The assay simultaneously detected five genes, namely 16S rRNA of the Staphylococcus genus, femA of S. aureus, mecA that encodes methicillin resistance, lukS that encodes production of Panton-Valentine leukocidin (PVL, a necrotizing cytotoxin, and one internal control. Specific primer pairs were successfully designed and simultaneously amplified the targeted genes. The analytical sensitivity and specificity of the pentaplex PCR assay was evaluated by comparing it with the conventional method. The analytical sensitivity of the pentaplex PCR at the DNA level was found to be 10 ng DNA. The analytical specificity was evaluated with 34 reference staphylococci and non-staphylococcal strains and was found to be 100%. The diagnostic evaluation of MRSA carried out using 230 clinical isolates, showed 97.6% of sensitivity, 99.3% of specificity, 98.8% of positive predictive value and 98.6% of negative predictive value compared to the conventional method. The presence of an internal control in the pentaplex PCR assay is important to exclude false-negative cases. Conclusion The pentaplex PCR assay developed was rapid and gave results within 4 h, which is essential for the identification of Staphylococcus spp., virulence and their resistance to methicillin. Our PCR assay may be used as an effective surveillance tool to survey the prevalence of MRSA and PVL-producing strains in hospitals and the community.

  4. A timescale for evolution, population expansion, and spatial spread of an emerging clone of methicillin-resistant Staphylococcus aureus

    Nübel, Ulrich; Dordel, Janina; Kurt, Kevin;

    2010-01-01

    or antibiotic resistance, together with the forces driving pathogen spread. Methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of hospital-acquired infections. We have investigated an MRSA strain (ST225) that is highly prevalent in hospitals in Central Europe. By using mutation discovery...... at 269 genetic loci (118,804 basepairs) within an international isolate collection, we ascertained extremely low diversity among European ST225 isolates, indicating that a recent population bottleneck had preceded the expansion of this clone. In contrast, US isolates were more divergent, suggesting...... they represent the ancestral population. While diversity was low, however, our results demonstrate that the short-term evolutionary rate in this natural population of MRSA resulted in the accumulation of measurable DNA sequence variation within two decades, which we could exploit to reconstruct its recent...

  5. PARTIAL CHARACTERIZATION OF A LYTIC METHICILLIN RESISTANT-STAPHYLOCOCCUS AUREUS BACTERIOPHAGE

    Sulaiman Al-Yousef

    2014-12-01

    Full Text Available A marked increase in the infection incidence caused by methicillin-resistant Staphylococcus aureus (MRSA strains has been noted in medical practice in recent years. This study was conducted to study the biological and characterize of MRSA-phage. Methicillin resistance of Staphylococcus aureus was detected and confirmed by determining of the MIC of oxacillin by the standard agar dilution method. Phage was biologically purified using single plaque technique, then phage characterization were studied using host range, adsorption time, particle morphology and its structural protein. MRSA phage showing lytic nature was purified by repeated plating after picking of single isolated plaques. This phage is active against all 11 isolates either of S. aureus or MRSA tested as hosts. Phage produced clear plaques indicating their lytic nature. This phage was concentrated employing polyethylene glycol (PEG-NaCl precipitation method. Morphologically, MRSA Phage has a hexagonal head having a long non-contractile tail, indicating his icosahedral nature. Adsorption studies showed 100% adsorption of MRSA-Phage after 35 minutes of exposure. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE experimentation indicated that the phage particles contain one major structural protein (about 30 Kda.

  6. Daptomycin approved in Japan for the treatment of methicillin-resistant Staphylococcus aureus

    Mori T

    2012-02-01

    Full Text Available Mao Hagihara1, Takumi Umemura1, Takeshi Mori1,2, Hiroshige Mikamo11Department of Infection Control and Prevention, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan; 2Division of Pharmaceutical Science, Faculty of Pharmacy, Meijo University, Nagoya, Aichi, JapanAbstract: Daptomycin is a lipoglycopeptide antibacterial drug that is rapidly bactericidal for methicillin-resistant Staphylococcus aureus (MRSA infection and has antibiotic activity against a wide range of Gram-positive organisms. It has been approved by the Ministry of Health, Labor and Welfare in Japan for the treatment for bacteremia, right-sided endocarditis, and skin and skin-structure infections, such as necrotizing fasciitis, due to MRSA on the basis of a Phase III trial conducted in Japan since July, 2011. In Japanese Phase I and III trials, daptomycin therapy given at 4 mg/kg and 6 mg/kg once per day was well tolerated and effective as standard therapy for the treatment of acute bacterial skin and skin-structure infections and bacteremia caused by MRSA, but side effects remain to be evaluated in large-scale trials.Keywords: daptomycin, methicillin-resistant Staphylococcus aureus (MRSA, Japan

  7. In vitro susceptibility of chloramphenicol against methicillin-resistant staphylococcus aureus

    To determine the in vitro susceptibility of chloramphenicol against methicillin-resistant Staphylococcus aureus. Study Design: Cross-sectional study. Place and Duration of Study: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from January to June 2012. Methodology: One hundred and seventy four isolates of methicillin-resistant Staphylococcus aureus were included in this study using cefoxitin (30 A g) disc for detection. Minimum inhibitory concentration (MIC) of chloramphenicol against MRSA was determined by using E-strip (AB BIO DISK). The susceptibility was determined by swabbing the Mueller-Hinton agar (MHA) plates with the resultant saline suspension of MRSA and applying E-strip of chloramphenicol from AB Biodisk Sweden and determining the MIC of chloramphenicol (in A g/ml). Clinical and Laboratory Standards Institute (CLSI) recommendations of A=8 A g/ml being sensitive, 16 A g/ml as intermediate and A 32 A g/ml as resistant were followed in interpreting the results. Results: Out of the 174 MRSA isolates, 132 (75.86%) isolates were susceptible to chloramphenicol with MICs of A=8 A g/ml, 38 (21.84%) were resistant A=32 A g/ml while 4 (2.30%) were in intermediate range with MIC of 16 A g/ml. Conclusion: Chloramphenicol has shown good in vitro activity against MRSA and is likely to have a key role in the treatment of MRSA infections providing us a good alternative to newer expensive antimicrobials in resource limited countries. (author)

  8. PREVALENCE OF HETEROGENEOUS GLYCOPEPTIDE INTERMEDIATE RESISTANCE IN METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS

    Manu Chaudhary

    2013-01-01

    Full Text Available Multidrug resistant Methicillin-Resistant Staphylococcus Aureus (MRSA is a major cause of nosocomial and community acquired infections and is on the rise. The aim of this investigation was to explore the prevalence of MRSA and heterogeneous Glycopeptide Intermediate Staphylococcus Aureus (hGISA in various clinical samples, to investigate the various antibiotic resistant determinant genes among these strains collected from north and west Indian hospitals and to evaluate the response of various drugs to these strains. A total of 413 clinical specimens collected from different hospitals were processed for the screening of S. aureus and MRSA. All these MRSA strains were further screened for hGISA on Mueller-Hinton agar containing 8 µg mL-1 teicoplanin or 6 µg mL-1 vancomycin. hGISA confirmed by the E-test method with a dense inoculum and a simplified method of population analysis. Susceptibility study was conducted according to the Clinical and Laboratory Standards Institute (CLSI methods. Among 211 S. aureus clinical isolates, 61.6% (130/211 of the isolates were confirmed to be MRSA which included maximum isolates from pus, blood, urine, wound swab and ear swab samples in decreasing order. hGISA strains were found in 8/130 (6.1% isolates. Vancoplus, a novel antibiotic adjuvant entity was found to be susceptible in 96.1 to 97.8% MRSA strains and showed intermediate response in 2.2 to 3.8% of isolates. Linezolid appeared to be second most active antibiotic with 48.0 to 81.2% susceptibility, followed by teicoplanin (41.3 to 56.2% susceptibility. There was 8.7 to 9.6% resistance observed in Linezolid which was increased to 48% in teicoplanin, to >60% indaptomycin and >75% in vancomycin. Interestingly, none of the isolates were susceptible to ceftriaxone and cefoperazone plus sulbactam. From the above study it can be concluded that prevelance of MRSA has reached a significant level and Vancoplus is the most effective in MRSA as well as h

  9. Mechanisms of methicillin-resistant Staphylococcus aureus pneumonia-induced intestinal epithelial apoptosis.

    Perrone, Erin E; Jung, Enjae; Breed, Elise; Dominguez, Jessica A; Liang, Zhe; Clark, Andrew T; Dunne, W Michael; Burd, Eileen M; Coopersmith, Craig M

    2012-07-01

    Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia-induced sepsis is a common cause of morbidity in the intensive care unit. Although pneumonia is initiated in the lungs, extrapulmonary manifestations occur commonly. In light of the key role the intestine plays in the pathophysiology of sepsis, we sought to determine whether MRSA pneumonia induces intestinal injury. FVB/N mice were subjected to MRSA or sham pneumonia and killed 24 h later. Septic animals had a marked increase in intestinal epithelial apoptosis by both hematoxylin-eosin and active caspase 3 staining. Methicillin-resistant S. aureus-induced intestinal apoptosis was associated with an increase in the expression of the proapoptotic proteins Bid and Bax and the antiapoptotic protein Bcl-xL in the mitochondrial pathway. In the receptor-mediated pathway, MRSA pneumonia induced an increase in Fas ligand but decreased protein levels of Fas, FADD, pFADD, TNF-R1, and TRADD. To assess the functional significance of these changes, MRSA pneumonia was induced in mice with genetic manipulations in proteins in either the mitochondrial or receptor-mediated pathways. Both Bid-/- mice and animals with intestine-specific overexpression of Bcl-2 had decreased intestinal apoptosis compared with wild-type animals. In contrast, Fas ligand-/- mice had no alterations in apoptosis. To determine if these findings were organism-specific, similar experiments were performed in mice subjected to Pseudomonas aeruginosa pneumonia. Pseudomonas aeruginosa induced gut apoptosis, but unlike MRSA, this was associated with increased Bcl-2 and TNF-R1 and decreased Fas. Methicillin-resistant S. aureus pneumonia thus induces organism-specific changes in intestinal apoptosis via changes in both the mitochondrial and receptor-mediated pathways, although the former may be more functionally significant. PMID:22592747

  10. Methicillin-resistant Staphylococcus aureus containing mecC in Swedish dairy cows

    Unnerstad Helle Ericsson

    2013-01-01

    Full Text Available Abstract Background Hitherto, methicillin-resistant Staphylococcus aureus (MRSA has not been detected in Swedish cattle. However, due to the report of mecC, a novel homologue to the mecA gene, there was reason to re-evaluate susceptibility results from strain collections of Staphylococcus aureus and test suspected isolates for the presence of mecC. Findings Bovine isolates of S. aureus with elevated minimum inhibitory concentrations of beta-lactams were retrospectively tested for presence of mecC. In four of the isolates mecC was detected. Conclusion In Sweden, this is the first finding of MRSA in cattle and the first detection of MRSA harbouring mecC of domestic animal origin. MRSA in animal populations has implications as a potential reservoir with risk for spread to humans. Occurrence of MRSA among Swedish cattle appears still very limited.

  11. Expression and inducibility in Staphylococcus aureus of the mecA gene, which encodes a methicillin-resistant S. aureus-specific penicillin-binding protein.

    Ubukata, K; Nonoguchi, R; Matsuhashi, M; Konno, M

    1989-01-01

    A beta-lactam-sensitive strain of Staphylococcus aureus could be converted to methicillin resistance by the introduction of a plasmid carrying the 4.3-kilobase HindIII chromosomal DNA fragment which encoded the mecA gene from a methicillin-resistant S. aureus. Transformant cells produced methicillin-resistant S. aureus-specific penicillin-binding protein constitutively, and additional insertion of an inducible penicillinase plasmid caused production of the pencillin-binding protein to become ...

  12. In-vitro and In-vivo Evaluation of Silymarin Nanoliposomes against Isolated Methicillin-resistant Staphylococcus aureus

    Faezizadeh, Zohreh; Gharib, Amir; Godarzee, Masoud

    2015-01-01

    Staphylococcus aureus is an opportunistic pathogen and remains a common cause of burn wound infections. Different studies have shown that entrapment of plant-derived compounds into liposomes could increase their anti-Staphylococcus aureus activity. Silymarin is the bioactive extract from the known plant Silybum marianum L. The objective of this study was to evaluate efficacy of silymarin in free and nanoliposomal forms against isolated methicillin-resistant Staphylococcus aureus (MRSA) strain...

  13. Biofilm formation on tympanostomy tubes depends on methicillin-resistant Staphylococcus aureus genetic lineage.

    Jotić, Ana; Božić, Dragana D; Milovanović, Jovica; Pavlović, Bojan; Ješić, Snežana; Pelemiš, Mijomir; Novaković, Marko; Ćirković, Ivana

    2016-03-01

    Bacterial biofilm formation has been implicated in the high incidence of persistent otorrhoea after tympanostomy tube insertion. The aim of the study was to investigate whether biofilm formation on tympanostomy tubes depends on the genetic profile of methicillin-resistant Staphylococcus aureus (MRSA) strains. Capacity of biofilm formation on fluoroplastic tympanostomy tubes (TTs) was tested on 30 MRSA strains. Identification and methicillin resistance were confirmed by PCR for nuc and mecA genes. Strains were genotypically characterised (SCCmec, agr and spa typing). Biofilm formation was tested in microtiter plate and on TTs. Tested MRSA strains were classified into SCCmec type I (36.7 %), III (23.3 %), IV (26.7 %) and V (13.3 %), agr type I (50 %), II (36.7 %) and III (13.3 %), and 5 clonal complexes (CCs). All tested MRSA strains showed ability to form biofilm on microtiter plate. Capacity of biofilm formation on TTs was as following: 13.3 % of strains belonged to the category of no biofilm producers, 50 % to the category of weak biofilm producers and 36.7 % to moderate biofilm producers. There was a statistically significant difference between CC, SCCmec and agr types and the category of biofilm production on TTs tubes (p tube otorrhea. PMID:25796207

  14. The Pleiotropic Antibacterial Mechanisms of Ursolic Acid against Methicillin-Resistant Staphylococcus aureus (MRSA).

    Wang, Chao-Min; Jhan, Yun-Lian; Tsai, Shang-Jie; Chou, Chang-Hung

    2016-01-01

    (1) BACKGROUND: Several triterpenoids were found to act synergistically with classes of antibiotic, indicating that plant-derived chemicals have potential to be used as therapeutics to enhance the activity of antibiotics against multidrug-resistant pathogens. However, the mode of action of triterpenoids against bacterial pathogens remains unclear. The objective of this study is to evaluate the interaction between ursolic acid against methicillin-resistant Staphylococcus aureus (MRSA); (2) METHODS: The ability of ursolic acid to damage mammalian and bacterial membranes was examined. The proteomic response of methicillin-resistant S. aureus in ursolic acid treatment was investigated using two-dimensional (2D) proteomic analysis; (3) RESULTS: Ursolic acid caused the loss of staphylococcal membrane integrity without hemolytic activity. The comparison of the protein pattern of ursolic acid-treated and normal MRSA cells revealed that ursolic acid affected a variety of proteins involved in the translation process with translational accuracy, ribonuclease and chaperon subunits, glycolysis and oxidative responses; (4) CONCLUSION: The mode of action of ursolic acid appears to be the influence on the integrity of the bacterial membrane initially, followed by inhibition of protein synthesis and the metabolic pathway. These findings reflect that the pleiotropic effects of ursolic acid against MRSA make it a promising antibacterial agent in pharmaceutical research. PMID:27399657

  15. Detection of methicillin-resistant Staphylococcus aureus (MRSA) using the NanoLantern Biosensor

    Strohsahl, Christopher M.; Miller, Benjamin L.; Krauss, Todd D.

    2009-02-01

    Staphylococcus aureus is a leading cause of human illness, and has developed the remarkable ability to resist the bactericidal capabilities of many of the world's leading antibiotics (i.e. MRSA). In an effort to enable rapid detection and treatment of MRSA infections, we have developed a DNA detection technology termed the NanoLantern(TM). The NanoLantern(TM) biosensor technology is based on the simple immobilization of a fluorophore-terminated DNA hairpin onto a gold chip. This produces a label-free sensor that allows for a positive response to be obtained without extensive processing of the sample, saving cost and increasing accuracy. We will also discuss a newly developed method of partial gene analysis, used to develop a DNA hairpin probe that is capable of detecting the presence of the mecR gene, a gene necessary for methicillin resistance to be present in S. aureus, with 100% sequence specificity. The successful incorporation of this probe into the NanoLantern(TM) platform, along with the concomitant development of the paired PCR assay has allowed for the successful detection of methicillin-resistance directly from a culture of S. aureus. These results represent an important step forward in terms of developing the ability to rapidly and effectively detect the presence of antibiotic resistance in bacterial infections.

  16. Cloning, expression and crystallization of dihydrodipicolinate reductase from methicillin-resistant Staphylococcus aureus

    Given the recent rise in antimicrobial resistance, there is an urgent need to identify and characterize new antibiotic drug targets. One such target is dihydrodipicolinate reductase (DHDPR), which is an essential bacterial enzyme that catalyzes the second step in the lysine-biosynthesis pathway. In this paper, the cloning, expression, purification and crystallization of DHDPR from methicillin-resistant S. aureus are presented. Dihydrodipicolinate reductase (DHDPR; EC 1.3.1.26) catalyzes the nucleotide (NADH/NADPH) dependent second step of the lysine-biosynthesis pathway in bacteria and plants. Here, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DHDPR from methicillin-resistant Staphylococcus aureus (MRSA-DHDPR) are presented. The enzyme was crystallized in a number of forms, predominantly with ammonium sulfate as a precipitant, with the best crystal form diffracting to beyond 3.65 Å resolution. Crystal structures of the apo form as well as of cofactor (NADPH) bound and inhibitor (2,6-pyridinedicarboxylate) bound forms of MRSA-DHDPR will provide insight into the structure and function of this essential enzyme and valid drug target

  17. Community-Associated Methicillin-Resistant Staphylococcus aureus in a Pediatric Emergency Department in Newfoundland and Labrador

    Erin Peebles

    2014-01-01

    Full Text Available BACKGROUND: First-generation cephalosporins and antistaphylococcal penicillins are typically the first choice for treating skin and soft tissue infections (SSTI, but are not effective for infections caused by methicillin-resistant Staphylococcus aureus (MRSA. It is currently unclear what percentage of SSTIs is caused by community-associated MRSA in different regions in Canada.

  18. Changing epidemiology of methicillin-resistant Staphylococcus aureus in Iceland from 2000 to 2008: a challenge to current guidelines

    Holzknecht, B.J.; Hardardottir, H.; Haraldsson, Gustav Helgi; Westh, Henrik; Valsdottir, F.; Boye, K.; Karlsson, Helena Sigrid; Kristinsson, Kári; Gudlaugsson, O.

    2010-01-01

    The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) is continuously changing. Iceland has a low incidence of MRSA. A "search and destroy" policy (screening patients with defined risk factors and attempting eradication in carriers) has been implemented since 1991. Clinical and...

  19. Potential Role of Pet Animals in Household Transmission of Methicillin-Resistant Staphylococcus aureus: A Narrative Review

    Bramble, Manuel; Morris, Daniel; Tolomeo, Pam; Lautenbach, Ebbing

    2011-01-01

    In this narrative review, we found numerous reports suggesting that dogs and cats may play a role in household methicillin-resistant Staphylococcus aureus (MRSA) transmission and recurrent MRSA infection in human contacts. Future work should emphasize elucidating more clearly the prevalence of MRSA in household pets and characterize transmission dynamics of MRSA humans and pet animals.

  20. Zinc-resistance gene CzrC identified in methicillin-resistant Staphylococcus hyicus isolated from pigs with exudative epidermitis.

    Slifierz, Mackenzie J; Park, Jeonghwa; Friendship, Robert M; Weese, J Scott

    2014-05-01

    Methicillin-resistant Staphylococcus hyicus (MRSH) was investigated for czrC, a gene conferring zinc-resistance. The czrC gene was identified in 50% (14/28) of MRSH isolates, representing 14 pigs with exudative epidermitis from 8 farms. Newly weaned pigs, which are particularly susceptible to exudative epidermitis, are commonly fed high levels of zinc oxide. PMID:24790238

  1. Automated DNA sequence-based early warning system for the detection of methicillin-resistant Staphylococcus aureus outbreaks

    Mellmann, Alexander; Friedrich, Alexander W; Rosenkötter, Nicole; Rothgänger, Jörg; Karch, Helge; Reintjes, Ralf; Harmsen, Dag

    2006-01-01

    BACKGROUND: The detection of methicillin-resistant Staphylococcus aureus (MRSA) usually requires the implementation of often rigorous infection-control measures. Prompt identification of an MRSA epidemic is crucial for the control of an outbreak. In this study we evaluated various early warning algo

  2. Prevalence and characterization of Methicillin-resistant Staphylococcus aureus isolates from retail meat and humans in Georgia

    There is increasing interest in the presence of Staphylococcus aureus, specifically methicillin-resistant S. aureus (MRSA), on retail meat products. In this study, staphylococci were isolated from retail pork and retail beef in Georgia and MRSA from the products were compared to human MRSA from the...

  3. Comparing Whole-Genome Sequencing with Sanger Sequencing for spa Typing of Methicillin-Resistant Staphylococcus aureus

    Bartels, Mette Damkjaer; Petersen, Andreas; Worning, Peder;

    2014-01-01

    spa typing of methicillin-resistant Staphylococcus aureus (MRSA) has traditionally been done by PCR amplification and Sanger sequencing of the spa repeat region. At Hvidovre Hospital, Denmark, whole-genome sequencing (WGS) of all MRSA isolates has been performed routinely since January 2013, and an...

  4. A new multiplex PCR for easy screening of methicillin-resistant Staphylococcus aureus SCCmec types I-V

    Boye, Kit; Bartels, Mette Damkjær; Andersen, Ina S;

    2007-01-01

    A multiplex PCR with four primer-pairs was designed to identify the five main known SCCmec types. A clear and easily discriminated band pattern was obtained for all five types. The SCCmec type was identified for 98% of 312 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA...

  5. The value of nasal mupirocin in containing an outbreak of methicillin- resistant Staphylococcus aureus in an orthopaedic unit

    S.P. Barrett

    1990-01-01

    textabstractAn outbreak of methicillin-resistant Staphylococcus aureus (MRSA) occurred in two adjacent orthopaedic wards following the admission of a known carrier. The outbreak was not contained by ward closure or by standard infection control measures. Eventually several nasal carriers were identi

  6. Methicillin-resistant Staphylococcus aureus in hospitals in Tbilisi, the Republic of Georgia, are variants of the Brazilian clone

    Bartels, M.D.; Nanuashvili, A.; Boye, K.;

    2008-01-01

    The purpose of this study was to characterise methicillin-resistant Staphylococcus aureus (MRSA) isolates from the Republic of Georgia, part of the former Soviet Union. Thirty-two non-duplicate MRSA isolates were collected in the period from May 2006 to February 2007. The patient data were analysed...

  7. Recurrent Methicillin-Resistant Staphylococcus aureus Cutaneous Abscesses and Selection of Reduced Chlorhexidine Susceptibility during Chlorhexidine Use

    Johnson, Ryan C.; Schlett, Carey D.; Crawford, Katrina; Lanier, Jeffrey B.; Merrell, D. Scott; Ellis, Michael W.

    2015-01-01

    We describe the selection of reduced chlorhexidine susceptibility during chlorhexidine use in a patient with two episodes of cutaneous USA300 methicillin-resistant Staphylococcus aureus abscess. The second clinical isolate harbors a novel plasmid that encodes the QacA efflux pump. Greater use of chlorhexidine for disease prevention warrants surveillance for resistance.

  8. Introduction of plasmid DNA into an ST398 livestock-associated methicillin-resistant Staphylococcus aureus strain

    MRS926 is a livestock-associated methicillin-resistant Staphylococcus aureus (MRSA) strain of sequence type (ST) 398. In order to facilitate in vitro and in vivo studies of this strain, we sought to tag it with a fluorescent marker. We cloned a codon-optimized gene for TurboGFP into a shuttle vector...

  9. Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) isolates of swine origin form robust biofilms

    Methicillin-resistant Staphylococcus aureus (MRSA) colonization of livestock animals is common and prevalence rates for pigs have been reported to be as high as 49%. One hypothesis to explain the high prevalence of MRSA in swine herds is the ability of these organisms to exist as biofilms. To invest...

  10. Adjunctive Hyperbaric Oxygen Therapy or Alone Antibiotherapy? Methicillin Resistant Staphylococcus aureus Mediastinitis in a Rat Model

    Tolga Kurt

    2015-10-01

    Full Text Available ABSTRACT OBJECTIVE: In the post-sternotomy mediastinitis patients, Staphylococcus aureus is the pathogenic microorganism encountered most often. In our study, we aimed to determine the efficacy of antibiotic treatment with vancomycin and tigecycline, alone or in combination with hyperbaric oxygen treatment, on bacterial elimination in experimental S. aureus mediastinitis. METHODS: Forty-nine adult female Wistar rats were used. They were randomly divided into seven groups, as follows: non-contaminated, contaminated control, vancomycin, tigecycline, hyperbaric oxygen, hyperbaric oxygen + vancomycin and hyperbaric oxygen + tigecycline. The vancomycin rat group received 10 mg/kg/day of vancomycin twice a day through intramuscular injection. The tigecycline group rats received 7 mg/kg/day of tigecycline twice a day through intraperitoneal injection. The hyperbaric oxygen group underwent 90 min sessions of 100% oxygen at 2.5 atm pressure. Treatment continued for 7 days. Twelve hours after the end of treatment, tissue samples were obtained from the upper part of the sternum for bacterial count assessment. RESULTS: When the quantitative bacterial counts of the untreated contaminated group were compared with those of the treated groups, a significant decrease was observed. However, comparing the antibiotic groups with the same antibiotic combined with hyperbaric oxygen, there was a significant reduction in microorganisms identified (P<0.05. Comparing hyperbaric oxygen used alone with the vancomycin and tigecycline groups, it was seen that the effect was not significant (P<0.05. CONCLUSION: We believe that the combination of hyperbaric oxygen with antibiotics had a significant effect on mediastinitis resulting from methicillin-resistant Staphylococcus aureus. Methicillin-resistant Staphylococcus aureus mediastinitis can be treated without requiring a multidrug combination, thereby reducing the medication dose and concomitantly decreasing the side effects.

  11. The Staphylococcus aureus Methicillin Resistance Factor FmtA Is a d-Amino Esterase That Acts on Teichoic Acids

    Rahman, Muhammad M.; Hunter, Howard N.; Prova, Shamina; Verma, Vidhu; Qamar, Aneela; Golemi-Kotra, Dasantila

    2016-01-01

    ABSTRACT The methicillin resistance factor encoded by fmtA is a core member of the Staphylococcus aureus cell wall stimulon, but its function has remained elusive for the past two decades. First identified as a factor that affects methicillin resistance in S. aureus strains, FmtA was later shown to interact with teichoic acids and to localize to the cell division septum. We have made a breakthrough in understanding FmtA function. We show that FmtA hydrolyzes the ester bond between d-Ala and t...

  12. [Molecular characterization of resistance mechanisms: methicillin resistance Staphylococcus aureus, extended spectrum β-lactamases and carbapenemases].

    Oteo, Jesús; Belén Aracil, María

    2015-07-01

    Multi-drug resistance in bacterial pathogens increases morbidity and mortality in infected patients and it is a threat to public health concern by their high capacity to spread. For both reasons, the rapid detection of multi-drug resistant bacteria is critical. Standard microbiological procedures require 48-72 h to provide the antimicrobial susceptibility results, thus there is emerging interest in the development of rapid detection techniques. In recent years, the use of selective and differential culture-based methods has widely spread. However, the capacity for detecting antibiotic resistance genes and their low turnaround times has made molecular methods a reference for diagnosis of multidrug resistance. This review focusses on the molecular methods for detecting some mechanisms of antibiotic resistance with a high clinical and epidemiological impact: a) Enzymatic resistance to broad spectrum β-lactam antibiotics in Enterobacteriaceae, mainly extended spectrum β-lactamases (ESBL) and carbapenemases; and b) methicillin resistance in Staphylococcus aureus. PMID:26320993

  13. Activity of medicinal plant extracts against hospital isolates of methicillin-resistant Staphylococcus aureus.

    Voravuthikunchai, S P; Kitpipit, L

    2005-06-01

    Aqueous and ethanolic extracts of ten traditional Thai medicinal plants were investigated for their ability to inhibit 35 hospital isolates of methicillin-resistant Staphylococcus aureus (MRSA). Nine medicinal plants displayed activity against all isolates tested. Ethanolic extracts of Garcinia mangostana, Punica granatum and Quercus infectoria were most effective, with MICs for MRSA isolates of 0.05-0.4, 0.2-0.4 and 0.2-0.4 mg/mL, respectively, and for S. aureus ATCC 25923 of 0.1, 0.2 and 0.1 mg/mL, respectively. MBCs for MRSA isolates were 0.1-0.4, 1.6-3.2 and 0.4-1.6 mg/mL, and for S. aureus ATCC 25923 were 0.4, 3.2 and 1.6 mg/mL, respectively. PMID:15882206

  14. Livestock Origin for a Human Pandemic Clone of Community-Associated Methicillin-Resistant Staphylococcus aureus

    Spoor, Laura E.; McAdam, Paul R.; Weinert, Lucy A.;

    2013-01-01

    -to-human host jumps by the major bovine S. aureus complex, CC97. Of note, one of the new clones was isolated from human infections on four continents, demonstrating its global dissemination since the host jump occurred over 40 years ago. The emergence of both human S. aureus clones coincided...... represent a reservoir for the emergence of new human-pathogenic S. aureus clones with the capacity for pandemic spread. These findings have major public health implications highlighting the importance of surveillance for early identification of emergent clones and improved transmission control measures......ABSTRACT The importance of livestock as a source of bacterial pathogens with the potential for epidemic spread in human populations is unclear. In recent years, there has been a global increase in community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections of healthy...

  15. Analysis of Methicillin-Resistant Staphylococcus aureus strains isolated in Palestine by arbitrarily primed PCR

    We report a study of 35 methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates collected between February and May 1998 from 4 different hospitals in Northern and Southern Palestine. The isolates were recovered from infection and carriage sites of patients and hospital environmental samples. The arbitrarily primed PCR (AP-PCR) method with two primers appears to be a useful tool, provides a fast and simple method for genetic analysis of MRSA infections and allows us to differentiate 22 different AP-PCR patterns. The major cluster, however, sharing common AP-PCR as well as a common PFGE pattern, represented 34% of all MRSA isolates. Isolates of these clusters were spread throughout the neonatal and intensive care units of Rafidya hospital during the entire period. In addition, these isolates were distributed in the southern part of Palestine as well. (author)

  16. Shortened Time to Identify Staphylococcus Species from Blood Cultures and Methicillin Resistance Testing Using CHROMAgar

    Shingo Chihara

    2009-01-01

    Full Text Available The ability to rapidly differentiate coagulase-negative staphylococcus (CoNS from Staphylococcus aureus and to determine methicillin resistance is important as it affects the decision to treat empiric antibiotic selection. The objective of this study was to evaluate CHROMagar S. aureus and CHROMagar MRSA (Becton Dickinson for rapid identification of Staphylococcus spp. directly from blood cultures. Consecutive blood culture bottles (BacT Alert 3D SA and SN, bioMérieux growing gram-positive cocci in clusters were evaluated. An aliquot was plated onto CHROMagar MRSA (C-MRSA and CHROMagar S. aureus (C-SA plates, which were read at 12 to 16 hours. C-SA correctly identified 147/147 S. aureus (100% sensitivity; 2 CoNS were misidentified as S. aureus (98% specificity. C-MRSA correctly identified 74/77 MRSA (96% sensitivity. None of the MSSA isolates grew on C-MRSA (100% specificity. In conclusion, CHROMagar is a rapid and sensitive method to distinguish MRSA, MSSA, and coagulase-negative Staphylococcus and may decrease time of reporting positive results.

  17. Successful Daptomycin Use in a Pediatric Patient With Acute, Bilateral Osteomyelitis Caused by Methicillin-Resistant Staphylococcus aureus

    Billups, Kelsey L.; Stultz, Jeremy S

    2015-01-01

    Staphylococcus aureus is the most common bacteria associated with the development of osteomyelitis in pediatric patients. Osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA) can be difficult to safely and effectively treat. Vancomycin, linezolid, and clindamycin are commonly used to treat osteomyelitis caused by MRSA. While adult studies suggest intravenous (IV) daptomycin may by beneficial for the treatment of MRSA osteomyelitis, it is not Food and Drug Administration ...

  18. In vitro activities of 28 antimicrobial agents against methicillin-resistant Staphylococcus aureus (MRSA) from a clinical setting in Malaysia.

    Neela, V; Sasikumar, M; Ghaznavi, G R; Zamberi, S; Mariana, S

    2008-09-01

    Methicillin-resistant Staphylococcus aureus (MRSA), an established nosocomial and emerging community pathogen associated with many fatalities due to its hyper-virulence and multiple drug resistant properties, is on the continuous rise. To update the current status on the susceptibility of local MRSA isolates to various classes of antibiotics and to identify the most potent antibiotics, thirty-two clinical isolates comprised of hospital acquired (HA) and community acquired (CA) infections were investigated by disk diffusion test. Of the 32 MRSA isolates, 14 (43.75%) and 18 (56.25%) were community and hospital acquired MRSA, respectively. All isolates were multiple drug resistant to more than 3 classes of antibiotics despite the source or specimen from which it was isolated. The oxacillin MICs for all isolates ranged from 2 to > or = 256 microg/ml. Twenty-five of 26 erythromycin-resistant MRSA isolates exhibited an inducible MLS(B) resistance phenotype while one showed an MS phenotype. More than half the isolates (68.75%) were resistant to at least one of the six aminoglycosides tested, with netilmicin as the most susceptible. The most effective antistaphylococcal agents were linezolid, vancomycin, teicoplanin and quinupristin/dalfopristin exhibited 100% susceptibility. Since MRSA is under continuous pressure of acquiring multiple drug resistance, it is imperative to focus routine surveillance on HA and CA-MRSA strains to monitor and limit the spread of this organism. PMID:19058585

  19. Prevalence and genotypic relatedness of methicillin resistant Staphylococcus aureus in a tertiary care hospital

    B A Fomda

    2014-01-01

    Full Text Available Background: Methicillin-resistant Staphylococcus aureus (MRSA is the most common multidrug-resistant pathogen causing nosocomial infections across the world. MRSA is not only associated with significant mortality and morbidity but also places a large economic strain on our health care system. MRSA isolates are also typically resistant to multiple, non-β-lactam antibiotics. We conducted a prospective study in a tertiary care hospital, to determine the prevalence of MRSA and to establish the clonal distribution of MRSA isolates recovered from various clinical specimens. Materials and Methods: Clinical samples were cultured and S. aureus was identified as per standard microbiological procedures. Susceptibility testing was done by agar disk diffusion and minimum inhibitory concentration (MIC method as recommended by CLSI. Methicillin resistance was detected by phenotypic methods namely, oxacillin disc diffusion (ODD, minimum inhibitory concentration (MIC of oxacillin, cefoxitin disk diffusion (CDD, and MIC of cefoxitin. Amplification of mecA gene by PCR was used as gold standard for detection of methicillin resistance. Pulsed field gel electrophoresis (PFGE typing was performed for MRSA isolates. Results: Out of 390 S. aureus isolates, 154 (39.48% isolates were MRSA and 236 (60.51% isolates were MSSA. Penicillin was the least effective antibacterial drug against the hospital associated S. aureus isolates with 85.64% resistance rate. All the isolates were susceptible to vancomycin. The MRSA showed a high level of resistance to all antimicrobials in general in comparison to the MSSA and the difference was statistically significant (P < 0.05. Multiplex PCR performed for all strains showed amplification of both the mecA and nucA genes in MRSA strains whereas MSSA strains showed amplification of only nucA gene. PFGE of these isolates showed 10 different patterns. Conclusion: Prevalence of MRSA in our hospital was 39.48%. Most of these isolates were

  20. Panton-Valentine Leukocidin-Positive and Toxic Shock Syndrome Toxin 1-Positive Methicillin-Resistant Staphylococcus aureus: a French Multicenter Prospective Study in 2008▿

    Robert, Jérôme; Tristan, Anne; Cavalié, Laurent; Decousser, Jean-Winoc; Bes, Michèle; Etienne, Jerome; Laurent, Frédéric

    2011-01-01

    The epidemiology of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) differs from country to country. We assess the features of the ST80 European clone, which is the most prevalent PVL-positive CA-MRSA clone in Europe, and the TSST-1 ST5 clone that was recently described in France. In 2008, all MRSA strains susceptible to fluoroquinolones and gentamicin and resistant to fusidic acid that were isolated in 104 French laboratories were characterized using agr alleles, spa...

  1. [Molecular diagnosis of methicillin-resistent Staphylococcus aureus: Methods and efficacy].

    Hell, M; Bauer, J W; Laimer, M

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) isolates are a serious public health problem whose ever-increasing rate is commensurate with the pressure it is exerting on the healthcare system. At present, more than 20% of clinical S. aureus isolates in German hospitals are methicillin-resistant, in Austria less than 10%. Strategies from low-prevalence countries show that this development is not necessarily inevitable. In the Scandinavian countries and the Netherlands, thanks to a rigorous prevention programme, MRSA prevalence has been kept at an acceptably low level (culturing involves a 2-3 day delay before the final results are available, rapid detection techniques (commonly referred to as MRSA rapid tests) using polymerase chain reaction (PCR) methods and, most recently, rapid culturing methods have been developed. The implementation of rapid tests reduces the time of detection of MRSA carriers from 48-72 to 2-5 h. Clinical evaluation data have shown that MRSA can thus be detected with very high sensitivity. Specificity, however, is sometimes impaired due to false-positive PCR signals occurring in mixed flora specimens. In order to rule out false-positive PCR results, a culture screen must always be carried out simultaneously. The data provide preliminary evidence that a PCR assay can reduce nosocomial MRSA transmission in high-risk patients or high-risk areas, whereas an approach that screens all patients admitted to the hospital is probably not effective. Information concerning the cost effectiveness of rapid MRSA tests is still sparse and thus the issue remains debated. PMID:26016829

  2. Transcriptional profiles of the response of methicillin-resistant Staphylococcus aureus to pentacyclic triterpenoids.

    Pooi Yin Chung

    Full Text Available Staphylococcus aureus is an important human pathogen in both hospital and the community that has demonstrated resistance to all currently available antibiotics over the last two decades. Multidrug-resistant isolates of methicillin-resistant S. aureus (MRSA exhibiting decreased susceptibilities to glycopeptides has also emerged, representing a crucial challenge for antimicrobial therapy and infection control. The availability of complete whole-genome nucleotide sequence data of various strains of S. aureus presents an opportunity to explore novel compounds and their targets to address the challenges presented by antimicrobial drug resistance in this organism. Study compounds α-amyrin [3β-hydroxy-urs-12-en-3-ol (AM], betulinic acid [3β-hydroxy-20(29-lupaene-28-oic acid (BA] and betulinaldehyde [3β-hydroxy-20(29-lupen-28-al (BE] belong to pentacyclic triterpenoids and were reported to exhibit antimicrobial activities against bacteria and fungi, including S. aureus. The MIC values of these compounds against a reference strain of methicillin-resistant S. aureus (MRSA (ATCC 43300 ranged from 64 µg/ml to 512 µg/ml. However, the response mechanisms of S. aureus to these compounds are still poorly understood. The transcription profile of reference strain of MRSA treated with sub-inhibitory concentrations of the three compounds was determined using Affymetrix GeneChips. The findings showed that these compounds regulate multiple desirable targets in cell division, two-component system, ABC transporters, fatty acid biosynthesis, peptidoglycan biosynthesis, aminoacyl-tRNA synthetase, ribosome and β-lactam resistance pathways which could be further explored in the development of therapeutic agents for the treatment of S. aureus infections.

  3. Identification of Functional Regulatory Residues of the β-Lactam Inducible Penicillin Binding Protein in Methicillin-Resistant Staphylococcus aureus

    Andreas N. Mbah

    2013-01-01

    Full Text Available Resistance to methicillin by Staphylococcus aureus is a persistent clinical problem worldwide. A mechanism for resistance has been proposed in which methicillin resistant Staphylococcus aureus (MRSA isolates acquired a new protein called β-lactam inducible penicillin binding protein (PBP-2′. The PBP-2′ functions by substituting other penicillin binding proteins which have been inhibited by β-lactam antibiotics. Presently, there is no structural and regulatory information on PBP-2′ protein. We conducted a complete structural and functional regulatory analysis of PBP-2′ protein. Our analysis revealed that the PBP-2′ is very stable with more hydrophilic amino acids expressing antigenic sites. PBP-2′ has three striking regulatory points constituted by first penicillin binding site at Ser25, second penicillin binding site at Ser405, and finally a single metallic ligand binding site at Glu657 which binds to Zn2+ ions. This report highlights structural features of PBP-2′ that can serve as targets for developing new chemotherapeutic agents and conducting site direct mutagenesis experiments.

  4. Prevalence and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus in ocular infections

    Maria Eugenia Vola

    2013-12-01

    Full Text Available PURPOSE: To study the prevalence of methicillin-resistant Staphylococcus aureus among S. aureus ocular infections in a tertiary health center in Brazil and compare antibiotic susceptibility patterns between MRSA and methicillin-susceptible S. aureus isolates. METHODS: Electronic records from the ocular microbiology laboratory of the Universidade Federal de São Paulo were retrospectively reviewed. During a 10-year period (between January 2000 and December 2009 all conjunctivitis, keratitis, and endophthalmitis cases with a positive culture for S. aureus were identified. Antibiotic susceptibility was determined using the Kirby-Bauer disk diffusion method. RESULTS: Five hundred sixty-six S. aureus isolates were identified; of those, 56 (9.9% were resistant to methicillin. Throughout the 10-year period, Staphylococcus aureus showed a significant increasing trend from 7.55% to 16.18% among overall S. aurues infections (p=0.001 and from 3.7% to 13.16% in conjunctivitis (p=0.001. Conversely, we did not observe the same trend among those with keratitis (p=0.38. Staphylococcus aureus isolates showed higher resistance rates to tobramycin, gentamicin, ciprofloxacin, gatifloxacin, and moxifloxacin when compared with S. aureus isolates (p< 0.001. All cases were susceptible to vancomycin. CONCLUSION: We observed an increasing trend in the overall prevalence of Staphylococcus aureus ocular infections and statistically significant higher resistance rates to commonly used antibiotics compared to Staphylococcus aureus. Our data supports the need for constant bacterial surveillance and should be taken into consideration before initiating empiric treatment of ocular infections.

  5. The change and significance of vancomycin minimal inhibitory concentration against methicillin-resistant Staphylococcus aureus isolates from inpatients with lower respiratory tract infection

    杨薇

    2013-01-01

    Objective To investigate the change and significance of vancomycin minimal inhibitory concentration(MIC) against methicillin-resistant Staphylococcus aureus(MRSA)isolates.Methods We analyzed the data of

  6. A study of the prevalence of methicillin-resistant Staphylococcus aureus in dermatology inpatients

    N Vijayamohan

    2014-01-01

    Full Text Available Background: Methicillin-resistant Staphylococcus aureus (MRSA is a cause of increased morbidity and mortality in debilitated and immunocompromised patients. Aims and Objectives: To study the prevalence of MRSA among dermatology inpatients and elucidate its predisposing factors and antibiotic sensitivity pattern. Materials and Methods: This prospective study involved all the inpatients in the dermatology ward with suspected bacterial infections, both primary and secondary. Gram′s stain, pus culture, and antibiotic sensitivity were the main tests done. Results: There were 61 patients in this study, with 36 males (59% and 25 females (41%. The age group maximally affected was 41-50 years (21.6%. Vesiculobullous disorders (22, 36.1% and eczemas (16, 26.2% were the commonest dermatoses with secondary infection. Extremities (72.1% and the trunk (26.2% were the commonest sites involved. Diabetes mellitus (DM was the commonest systemic illness (11.5%. Staphylococcus aureus was the commonest isolate, grown in 52 patients (85.2% of whom 16 (30.80% were MRSA positive. MRSA constituted 22.2% of the total bacterial isolates. All the MRSA isolates (100% were resistant to cloxacillin and oxacillin, while all the isolates (100% were sensitive to vancomycin and linezolid. Conclusions: The prevalence of MRSA in this study was high. It was most commonly seen in patients with vesiculobullous disorders. A high sensitivity of MRSA was found to amikacin. There was no relation between prolonged antibiotic therapy and MRSA in this study.

  7. Methicillin-Resistant Staphylococcus aureus Recovered from Healthcare- and Community-Associated Infections in Egypt

    Mohamed Abdel-Maksoud

    2016-01-01

    Full Text Available Background. Methicillin-resistant Staphylococcus aureus (MRSA has created significant epidemiological, infection-control, and therapeutic management challenges during the past three decades. Aim. To analyze the pattern of resistance of healthcare- and community-associated MRSA in Egypt and the trend of resistance of HA-MRSA over time (2005–2013. Methods. MRSA isolates were recovered from healthcare-associated (HA and community-associated (CA Staphylococcus aureus (S. aureus infections. They were tested against 11 antimicrobial discs and the minimal inhibitory concentration (MIC of vancomycin was determined. Inducible clindamycin resistance (iMLSB was also screened using D-test. Findings. Of 631 S. aureus, MRSA was identified in 343 (76.6% and 21 (11.5% of HA and CA S. aureus isolates, respectively. The proportion of HA-MRSA increased significantly from 48.6% in 2005 to 86.8% in 2013 (p value < 0.001. Multidrug resistance (MDR was observed in 85.8% of HA-MRSA and 48.6% of CA-MRSA. Vancomycin intermediate resistant S. aureus (VISA was detected in 1.2% of HA-MRSA and none was detected in CA-MRSA. Among HA-MRSA strains, 5.3% showed iMLSB compared to 9.5% among CA-MRSA. Conclusion. The upsurge of the prevalence rates of HA-MRSA over time is alarming and urges for an effective infection control strategy and continuous monitoring of antimicrobial use.

  8. Methicillin-Resistant Staphylococcus aureus Recovered from Healthcare- and Community-Associated Infections in Egypt.

    Abdel-Maksoud, Mohamed; El-Shokry, Mona; Ismail, Ghada; Hafez, Soad; El-Kholy, Amani; Attia, Ehab; Talaat, Maha

    2016-01-01

    Background. Methicillin-resistant Staphylococcus aureus (MRSA) has created significant epidemiological, infection-control, and therapeutic management challenges during the past three decades. Aim. To analyze the pattern of resistance of healthcare- and community-associated MRSA in Egypt and the trend of resistance of HA-MRSA over time (2005-2013). Methods. MRSA isolates were recovered from healthcare-associated (HA) and community-associated (CA) Staphylococcus aureus (S. aureus) infections. They were tested against 11 antimicrobial discs and the minimal inhibitory concentration (MIC) of vancomycin was determined. Inducible clindamycin resistance (iMLSB) was also screened using D-test. Findings. Of 631 S. aureus, MRSA was identified in 343 (76.6%) and 21 (11.5%) of HA and CA S. aureus isolates, respectively. The proportion of HA-MRSA increased significantly from 48.6% in 2005 to 86.8% in 2013 (p value Multidrug resistance (MDR) was observed in 85.8% of HA-MRSA and 48.6% of CA-MRSA. Vancomycin intermediate resistant S. aureus (VISA) was detected in 1.2% of HA-MRSA and none was detected in CA-MRSA. Among HA-MRSA strains, 5.3% showed iMLSB compared to 9.5% among CA-MRSA. Conclusion. The upsurge of the prevalence rates of HA-MRSA over time is alarming and urges for an effective infection control strategy and continuous monitoring of antimicrobial use. PMID:27433480

  9. Bactericidal Effects of Charged Silver Nanoparticles in Methicillin-resistant Staphylococcus aureus

    Romero-Urbina, Dulce; Velazquez-Salazar, J. Jesus; Lara, Humberto H.; Arellano-Jimenez, Josefina; Larios, Eduardo; Yuan, Tony T.; Hwang, Yoon; Desilva, Mauris N.; Jose-Yacaman, Miguel

    2015-03-01

    The increased number of infections due to antibiotic-resistant bacteria is a major concern to society. The objective of this work is to determine the effect of positively charged AgNPs on methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus(MRSA) cell wall using advanced electron microscopy techniques. Positively charged AgNPs suspensions were synthesized via a microwave heating technique. The suspensions were then characterized by Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) showing AgNPs size range from 5 to 30 nm. MSSA and MRSA were treated with positively charged AgNPs concentrations ranging from 0.06 mM to 31 mM. The MIC50 studies showed that viability of MSSA and MRSA could be reduced by 50% at a positively charged AgNPs concentration of 0.12 mM supported by Scanning-TEM (STEM) images demonstrating bacteria cell wall disruption leading to lysis after treatment with AgNPs. The results provide insights into one mechanism in which positively charged AgNPs are able to reduce the viability of MSSA and MRSA. This research is supported by National Institute on Minority Health and Health Disparities (G12MD007591) from NIH, NSF-PREM Grant No. DMR-0934218, The Welch Foundation and NAMRU-SA work number G1009.

  10. Diversity of staphylococcal cassette chromosome mec elements in predominant methicillin-resistant Staphylococcus aureus clones in a small geographic area.

    Basset, Patrick; Senn, Laurence; Vogel, Valérie; Zanetti, Giorgio; Blanc, Dominique S

    2010-11-01

    Recent population genetic studies suggest that staphylococcal cassette chromosome mec (SCCmec) was acquired much more frequently than previously thought. In the present study, we aimed to investigate the diversity of SCCmec elements in a local methicillin-resistant Staphylococcus aureus (MRSA) population. Each MRSA isolate (one per patient) recovered in the Vaud canton of Switzerland from January 2005 to December 2008 was analyzed by the double-locus sequence typing (DLST) method and SCCmec typing. DLST analysis indicated that 1,884/2,036 isolates (92.5%) belong to four predominant clones. As expected from the local spread of a clone, most isolates within clones harbored an identical SCCmec type. However, three to seven SCCmec types have been recovered in every predominant DLST clone, suggesting that some of these elements might have been acquired locally. This pattern could also be explained by distinct importations of related isolates into the study region. The addition of a third highly variable locus to further increase the discriminatory power of typing as well as epidemiological data suggested that most ambiguous situations were explained by the second hypothesis. In conclusion, our study showed that even if the acquisition of new SCCmec elements at a local level likely occurs, it does not explain all the diversity observed in the study region. PMID:20713672

  11. Methicillin-resistant Staphylococcus aureus-induced thrombo-inflammatory response is reduced with timely antibiotic administration

    Franks, Zechariah; Campbell, Robert A.; de Abreu, Adriana Vieira; Holloway, Jeffrey T.; Marvin, James E.; Kraemer, Bjoern F.; Zimmerman, Guy A.; Weyrich, Andrew S.; Rondina, Matthew T.

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) induces a pro-thrombotic and pro-inflammatory milieu. Although timely antibiotic administration in MRSA sepsis may improve outcomes by arresting bacterial growth, the effects of antibiotics on mitigating injurious thrombo-inflammatory cellular responses remains unexplored. Using a newly developed human whole blood model and an in vivo mouse model of MRSA infection, we examined how antibiotics inhibit MRSA induced thrombo-inflammatory pathways...

  12. Survey of Staphylococcus isolates among hospital personnel, environment and their antibiogram with special emphasis on methicillin resistance

    Shobha K; Rao P; Thomas J

    2005-01-01

    The objective of this study was to find the prevalence of Staphylococcus spp. carriage among hospital personnel and hospital environment and their antibiogram with special emphasis on methicillin resistance. A total of 205 samples from hospital personnel and environment were collected from casualty, oncology and multidisciplinary cardiac unit ward of Kasturba Medical College Hospital, Manipal. Samples were collected using sterile cotton wool swabs and inoculated into brain heart infusion bro...

  13. The dynamics of methicillin-resistant Staphylococcus aureus exposure in a hospital model and the potential for environmental intervention

    Plipat, Nottasorn; Spicknall, Ian H.; James S. Koopman; Eisenberg, Joseph NS

    2013-01-01

    Background Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of healthcare-associated infections. An important control strategy is hand hygiene; however, non-compliance has been a major problem in healthcare settings. Furthermore, modeling studies have suggested that the law of diminishing return applies to hand hygiene. Other additional control strategies such as environmental cleaning may be warranted, given that MRSA-positive individuals constantly shed contaminated desqu...

  14. Evaluation of Once-Daily Vancomycin against Methicillin-Resistant Staphylococcus aureus in a Hollow-Fiber Infection Model

    Nicasio, Anthony M.; Bulitta, Jürgen B.; Lodise, Thomas P.; D'Hondt, Rebecca E.; Kulawy, Robert; Louie, Arnold; Drusano, George L.

    2012-01-01

    For methicillin-resistant Staphylococcus aureus (MRSA) infections, data suggest that the clinical response is significantly better if the total vancomycin area under the concentration-time curve (AUC)/MIC ratio is ≥400. While the AUC/MIC ratio is the accepted pharmacokinetic/pharmacodynamic (PK/PD) index for vancomycin, this target has been achieved using multiple daily doses. We are unaware of a systematically designed dose fractionation study to compare the bactericidal activity of once-dai...

  15. Comparison of Genetic Backgrounds of Methicillin-Resistant and -Susceptible Staphylococcus aureus Isolates from Portuguese Hospitals and the Community

    de Sousa, M. Aires; Conceição, T.; Simas, C.; de Lencastre, H.

    2005-01-01

    In order to understand the origins of the dominant methicillin-resistant Staphylococcus aureus (MRSA) clones in Portuguese hospitals, we compared the genetic backgrounds of nosocomial MRSA with methicillin-susceptible S. aureus (MSSA) isolates from the same hospitals (n = 155) and from the community (n = 157) where they were located. Pulsed-field gel electrophoresis, spa typing, multilocus sequence typing, and agr type analysis revealed that the genetic backgrounds correspondent to the domina...

  16. Predischarge Postpartum Methicillin Resistant Staphylococcus aureus Infection and Group B Streptococcus Carriage at the Individual and Hospital Levels

    Parriott, Andrea M.; Brown, Joelle M.; Arah, Onyebuchi A.

    2014-01-01

    Background. We sought to characterize the relationship between individual group B streptococcus (GBS) colonization and pre-discharge postpartum methicillin resistant Staphylococcus aureus (MRSA) infection in United States women delivering at term. We also sought to examine the association between hospital GBS colonization prevalence and MRSA infection. Materials and Methods. Data was from the Nationwide Inpatient Sample, a representative sample of United States community hospitals. Hierarchic...

  17. Recurrent shunt associated ventriculitis caused by methicillin-resistant Staphylococcus aureus: Case with fatal outcome despite linezolid therapy

    Sadia Khan

    2012-01-01

    Full Text Available Ventriculoperitoneal shunt-associated ventriculitis is a serious though under-reported nosocomial complication of neurocritical settings. The treatment of CNS Methicillin-resistant Staphylococcus aureus (MRSA infections is usually successful with vancomycin or linezolid. Here, we report a case of ventriculitis due to MRSA following a shunt infection, which did not show clinical response to linezolid therapy. With the increasing use of invasive procedures, nosocomial infections have increased exponentially. Exercising extreme care in such CNS procedures becomes very important.

  18. Methicillin-resistant Staphylococcus aureus colonization and disease severity in atopic dermatitis: A cross-sectional study from South India

    Soumya Jagadeesan; George Kurien; Manjula Velikkakathu Divakaran; Sadeep Melethil Sadanandan; K Sobhanakumari; Sarin, A

    2014-01-01

    Background: Colonization by methicillin-resistant Staphylococcus aureus (MRSA) in atopic dermatitis is little studied but has therapeutic implications. It may have a role in disease severity given the additional virulence factors associated. Aims: Our aims were to record the proportion of patients with MRSA colonization in atopic dermatitis and to ascertain if any association exists between MRSA colonization and disease severity. Methods: An observational cross-sectional study involving child...

  19. Risk factors for Staphylococcus aureus and methicillin-resistant S aureus colonization among health care workers in pediatrics departments.

    Gomes, Ivete Martins; Marlow, Mariel Asbury; Pinheiro, Marcos Gabriel; de Freitas, Maria de Fátima Nogueira; Fonseca, Fernanda Fernandes; Cardoso, Claudete Aparecida Araújo; Aguiar-Alves, Fábio

    2014-08-01

    Risk factors for Staphylococcus aureus and methicillin-resistant S aureus (MRSA) were evaluated for 178 health care workers from a public hospital pediatrics department in Brazil. Colonization rates were 33.1% for S aureus and 5.1% for MRSA. Risk factors for S aureus colonization differed from those for MRSA. Results suggest nurses with prolonged pediatric patient contact in inpatient units are at higher risk for MRSA colonization. PMID:25087145

  20. Rapid Detection of Methicillin-Resistant Staphylococcus aureus Directly from Sterile or Nonsterile Clinical Samples by a New Molecular Assay

    Francois, Patrice; Pittet, Didier; Bento, Manuela; Pepey, Béatrice; Vaudaux, Pierre; Lew, Daniel; Schrenzel, Jacques

    2003-01-01

    A rapid procedure was developed for detection and identification of methicillin-resistant Staphylococcus aureus (MRSA) directly from sterile sites or mixed flora samples (e.g., nose or inguinal swabs). After a rapid conditioning of samples, the method consists of two main steps: (i) immunomagnetic enrichment in S. aureus and (ii) amplification-detection profile on DNA extracts using multiplex quantitative PCR (5′-exonuclease qPCR, TaqMan). The triplex qPCR assay measures simultaneously the fo...

  1. Modulation of Fibronectin Adhesins and Other Virulence Factors in a Teicoplanin-Resistant Derivative of Methicillin-Resistant Staphylococcus aureus

    Renzoni, Adriana; Francois, Patrice; Li, Dongmei; Kelley, William L; Lew, Daniel P.; Vaudaux, Pierre; Schrenzel, Jacques

    2004-01-01

    The impact of glycopeptide resistance on the molecular regulation of Staphylococcus aureus virulence and attachment to host tissues is poorly documented. We compared stable teicoplanin-resistant methicillin-resistant S. aureus (MRSA) strain 14-4 with its teicoplanin-susceptible MRSA parent, strain MRGR3, which exhibits a high degree of virulence in a rat model of chronic foreign body MRSA infection. The levels of fibronectin-mediated adhesion and surface display of fibronectin-binding protein...

  2. Genetic Relatedness, Antimicrobial and Biocide Susceptibility Comparative Analysis of Methicillin-Resistant and -Susceptible Staphylococcus pseudintermedius from Portugal

    Couto, Natacha; Belas, Adriana; Couto, Isabel; Perreten, Vincent; Pomba, Constança

    2014-01-01

    Forty methicillin-resistant and -susceptible Staphylococcus pseudintermedius (MRSP and MSSP, respectively) from colonization and infection in dogs and cats were characterized for clonality, antimicrobial, and biocide susceptibility. MSSP were genetically more diverse than MRSP by multi-locus sequence typing and pulsed-field gel electrophoresis. Three different spa types (t06, t02, t05) and two SCCmec types (II-III and V) were detected in the MRSP isolates. All MRSP and two MSSP strains were m...

  3. Subinhibitory concentrations of imipenem induce increased resistance to methicillin and imipenem in vitro in methicillin-resistant Staphylococcus aureus.

    Forbes, B A; McClatchey, K D; Schaberg, D R

    1984-01-01

    Methicillin-resistant (MR) Staphylococcus aureus that was susceptible to less than 0.75 micrograms of imipenem per ml demonstrated inducible resistance. MR S. aureus preincubated with 0.05 microgram of imipenem per ml grew in medium with an imipenem concentration of 32 micrograms/ml, and methicillin MICs increased 20-fold. Non-MR S. aureus exhibited no induction. Preincubation with methicillin produced no effect. Induction appeared to be a unique interaction of imipenem with MR S. aureus.

  4. Chlorhexidine resistance in methicillin-resistant Staphylococcus aureus or just an elevated MIC? An in vitro and in vivo assessment.

    Cookson, B D; Bolton, M C; Platt, J H

    1991-01-01

    Chlorhexidine (Hibiscrub; ICI) is generally accepted to be effective as an antiseptic hand wash for methicillin-susceptible Staphylococcus aureus (MSSA), but there is dispute whether the chlorhexidine MIC for methicillin-resistant S. aureus (MRSA) strains is higher than that for MSSA strains and, indeed, whether it is relevant. In addition, the link between resistance to chlorhexidine, gentamicin, and "nucleic acid-binding" compounds (NAB; which code, in particular, for propamidine isethionat...

  5. Comparison of Methods for Evaluation of the Bactericidal Activity of Copper-Sputtered Surfaces against Methicillin-Resistant Staphylococcus aureus

    Rio, Laura; Kusiak-Nejman, Ewelina; Kiwi, John; Betrisey, Bertrand; Pulgarin, Cesar; Trampuz, Andrej; Bizzini, Alain

    2012-01-01

    Bacteria can survive on hospital textiles and surfaces, from which they can be disseminated, representing a source of health care-associated infections (HCAIs). Surfaces containing copper (Cu), which is known for its bactericidal properties, could be an efficient way to lower the burden of potential pathogens. The antimicrobial activity of Cu-sputtered polyester surfaces, obtained by direct-current magnetron sputtering (DCMS), against methicillin-resistant Staphylococcus aureus (MRSA) was tes...

  6. Uniformity of Glycyl Bridge Lengths in the Mature Cell Walls of Fem Mutants of Methicillin-Resistant Staphylococcus aureus

    Sharif, Shasad; Kim, Sung Joon; Labischinski, Harald; Chen, Jiawei; Schaefer, Jacob

    2013-01-01

    Peptidoglycan (PG) composition in intact cells of methicillin-resistant Staphylococcus aureus (MRSA) and its isogenic Fem mutants has been characterized by measuring the glycine content of PG bridge structures by solid-state nuclear magnetic resonance (NMR). The glycine content estimated from integrated intensities (rather than peak heights) in the cell walls of whole cells was increased by approximately 30% for the FemA mutant and was reduced by 25% for the FemB mutant relative to expected v...

  7. Prevalence and Risk Factor Analysis for Methicillin-Resistant Staphylococcus aureus Nasal Colonization in Children Attending Child Care Centers▿

    Miller, Melissa B.; David J. Weber; Goodrich, Jennifer S.; Popowitch, Elena B.; Poe, Michele D.; Nyugen, Viet; Shope, Timothy R.; Foster, David T.; Miller, James R; Kotch, Jonathan

    2011-01-01

    Children attending child care centers (CCCs) are at increased risk for infections, including those caused by methicillin-resistant Staphylococcus aureus (MRSA). Nasal colonization often precedes infection, and MRSA colonization has been associated with increased infection risk. Community-associated MRSA (CA-MRSA) has caused increased MRSA infections in the general population, including children. Little is known about the frequency of MRSA nasal colonization in young children, particularly in ...

  8. Methicillin-resistant Staphylococcus aureus nasal cariage among hospitalized patients and healthcare workers in the Clinical center of Serbia

    Ćirković Ivana; Đukić Slobodanka; Carević Biljana; Mazić Nataša; Mioljević Vesna; Stepanović S.

    2014-01-01

    The aim of the present study was to provide the first comprehensive analysis of methicillin-resistant Staphylococcus aureus (MRSA) carriage among patients and healthcare workers (HCWs) in the largest healthcare facility in Serbia. Specimens from anterior nares obtained from 195 hospitalized patients and 105 HCWs were inoculated after broth enrichment onto chromogenic MRSA-ID medium. In total, 21 of 300 specimens yielded MRSA. Among hospitalized patients, 7.7% ...

  9. Transmission and Persistence of Livestock-Associated Methicillin-Resistant Staphylococcus aureus among Veterinarians and Their Household Members

    Bosch, T; Verkade, E.; van Luit, M.; Landman, F.; Kluytmans, J.; Schouls, L.M.

    2014-01-01

    After the first isolation of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in 2003, this MRSA variant quickly became the predominant MRSA obtained from humans as part of the Dutch national MRSA surveillance. Previous studies have suggested that human-to-human transmission of LA-MRSA, compared to that of other MRSA lineages, rarely occurs. However, these reports describe the transmission of LA-MRSA based on epidemiology and limited molecular characterization of iso...

  10. Molecular and Clinical Characteristics of Hospital and Community Onset Methicillin-Resistant Staphylococcus aureus Strains Associated with Bloodstream Infections

    Wang, Shu-Hua; Hines, Lisa; van Balen, Joany; José R Mediavilla; Pan, Xueliang; Hoet, Armando E; Kreiswirth, Barry N.; Pancholi, Preeti; Stevenson, Kurt B.

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSI) are classified epidemiologically as health care-associated hospital onset (HAHO)-, health care-associated community onset (HACO)-, or community-associated (CA)-MRSA. Clinical and molecular differences between HAHO- and HACO-MRSA BSI are not well known. Thus, we evaluated clinical and molecular characteristics of MRSA BSI to determine if distinct features are associated with HAHO- or HACO-MRSA strains. Molecular ge...

  11. Staphylococcal Cassette Chromosome mec and Panton-Valentine Leukocidin Characterization of Methicillin-Resistant Staphylococcus aureus Clones▿

    Moroney, Shannon M.; Heller, Loree C.; Arbuckle, Jesse; Talavera, Monica; Widen, Ray H.

    2006-01-01

    Staphylococcal cassette chromosome mec (SCCmec) types and Panton-Valentine leukocidin (PVL) gene carriage were compared among suspected community-associated methicillin-resistant Staphylococcus aureus MRSA (CA-MRSA) and health care-associated MRSA (HA-MRSA) isolates. CA-MRSA isolates carried the SCCmec type IV complex, and most were PVL positive. The HA-MRSA isolates carried the SCCmec type II complex and did not harbor the PVL genes.

  12. Use of BBL CHROMagar MRSA Medium for Identification of Methicillin-Resistant Staphylococcus aureus Directly from Blood Cultures

    Pape, John; Wadlin, Jill; Nachamkin, Irving

    2006-01-01

    We evaluated the ability of BBL CHROMagar MRSA medium (Becton Dickinson, Sparks, MD) to identify methicillin-resistant Staphylococcus aureus (MRSA) directly upon subculture from positive blood culture bottles. There were 124 MRSA isolates recovered from blood cultures in the study. BBL CHROMagar MRSA medium was highly sensitive (97.6% [121/124] at 18 to 24 h of incubation and 100% [124/124] at 48 h) and 99.9% specific for identifying MRSA from positive blood cultures.

  13. Does nasal cocolonization by methicillin-resistant coagulase-negative staphylococci and methicillin-susceptible Staphylococcus aureus strains occur frequently enough to represent a risk of false-positive methicillin-resistant S. aureus determinations by molecular methods?

    Becker, Karsten; Pagnier, Isabelle; Schuhen, Brigitte; Wenzelburger, Frauke; Friedrich, Alexander W; Kipp, Frank; Peters, Georg; von Eiff, Christof

    2006-01-01

    By analyzing the colonization of the anterior nares in cardiothoracic surgery patients on admission, nasal cocolonization by methicillin-susceptible Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci was detected in 8/235 (3.4%) specimens. Consequently, in a low-methici

  14. Sanitary status and incidence of methicillin-resistant Staphylococcus aureus and Clostridium difficile within Canadian hotel rooms.

    Xu, Changyun; Weese, Scott J; Namvar, Azadeh; Warriner, Keith

    2015-04-01

    The study described in this article aimed at establishing a baseline assessment of the sanitary status of ice and guest rooms within Canadian hotels. Collectively, 54 hotel rooms belonging to six different national chains were sampled. High-contact surfaces (comforter, alarm clock, bedside lamp, TV remote, bathroom countertop, faucet, and toilet seat) were sampled using adenosine triphosphate (ATP) swabs and replicate organism detection and counting plates. ATP swab readings ranged from 2.12 to 4.42 log relative light units. Coliforms were recovered from 36% of surfaces with high prevalence being recovered from the comforter, TV remote, bathroom countertop, faucet, and toilet seat. Oxacillin-resistant bacteria were recovered from 19% of surfaces with 46% of isolates confirmed as methicillin-resistant Staphylococcus aureus. Two toxigenic Clostridium difficile isolates were recovered in the course of the study. Collectively, 24% of the ice samples harbored coliforms with a single sample testing positive for E. coli. The authors' study demonstrates that hotel rooms represent a potential source of community-acquired infections and the need for enhanced sanitation practices. PMID:25876260

  15. Characterization of methicillin resistant Staphylococcus aureus strains among inpatients and outpatients in a referral hospital in Tehran, Iran.

    Rahimi, Fateh; Shokoohizadeh, Leili

    2016-08-01

    Methicillin resistant Staphylococcus aureus is one of the most common causes of a variety of infections ranging from wound infections to urinary tract infections (UTI) in hospital and community. In this study during 3 years we characterized the antibiotic resistance patterns of 491 hospital acquired MRSA and community associated MRSA strains by the guidelines of clinical and laboratory standard institute. A combination of high resolution PhP typing method and SCCmec typing were used for clonal dissemination of isolates. Among all 491 MRSA strains, diverse PhP types consisting of 29 common types (CTs) and 4 single types (STs) and also 2 different SCCmec types (III and IVa) were detected. In addition, 18 CTs were common among CA- and HA-MRSA strains and the presence of all 4 STs was limited to HA-MRSA strains. All isolates were resistant to penicillin and high level resistance was observed against ciprofloxacin, erythromycin, tobramycin and kanamycin and the rate of resistance to most of the antibiotic tested among HA-MRSA was significantly higher than CA-MRSA isolates. Moreover, all isolates showed susceptibility to linezolid, vancomycin and quinupristin-dalfopristin and very low resistance to fusidic acid, nitrofurantoin and chloramphenicol were detected. Our findings illustrated the increasing rate of clonal dissemination and persistence of highly antibiotic resistant CA-MRSA strains in Tehran hospitals, and also indicated the important role of the hospitals as the reservoir of MRSA strains. PMID:27265678

  16. Longitudinal study of horses for carriage of methicillin-resistant Staphylococcus aureus following wound infections.

    Bergström, Karin; Bengtsson, Björn; Nyman, Ann; Grönlund Andersson, Ulrika

    2013-05-01

    An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infections in horses in Sweden raised questions concerning the risk posed by horses to their surroundings following MRSA infections. This initiated a longitudinal study to investigate how long MRSA-infected horses remained positive and to test the sensitivity of different anatomical sampling sites for detection of MRSA. Between October 2008 and June 2010, 9 of 15 horses notified as having MRSA-infected wounds fitted the case criteria for the study. The cases were sampled at five anatomical sites (nostrils, corner of mouth, pastern, perineum, and previous infection site) on six to seven occasions or more during approximately 12-18 months. MRSA-specific broth and agar were used for culture. Verified MRSA isolates were spa-typed. The sensitivity of sampling sites was calculated. The most sensitive sampling site was the nostrils, with a sensitivity of 0.91 (95% CI: 0.59-1.00). The other test sites had a sensitivity of 0-0.09. Individual cases tested positive, but with time all tested negative. The observed carriage time ranged from 55 to 711 days (median=143, IQR: 111-172 days), but these data should be interpreted with caution since only a small number of cases were studied. PMID:23428383

  17. Ceftaroline Fosamil Use in 2 Pediatric Patients With Invasive Methicillin-Resistant Staphylococcus aureus Infections.

    Williams, Amanda W; Newman, Patrick M; Ocheltree, Sara; Beaty, Rachel; Hassoun, Ali

    2015-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is one of the most common pathogens causing pediatric infections including skin and soft tissue infections, pyogenic arthritis, osteomyelitis, and septic shock. For decades, patients were treated with antibiotics such as vancomycin and clindamycin, but there is an increasing incidence of resistance to these traditional therapies. We describe 2 cases of patients with CA-MRSA invasive infections with bacteremia who experienced vancomycin therapy failure but who were successfully treated with ceftaroline fosamil. Case 1 involves an 8-year-old Hispanic male who was diagnosed with CA-MRSA bacteremia, thigh abscess, and osteomyelitis. The patient was admitted to the pediatric intensive care unit in septic shock. Case 2 involves an 8-year-old Caucasian male who was diagnosed with CA-MRSA sepsis, right arm abscess, and osteomyelitis. We were able to successfully treat both patients with CA-MRSA sepsis and invasive infection-who failed vancomycin therapy-with ceftaroline fosamil with no adverse efiects. Despite the positive outcome in both pediatric patients, clinical trials with ceftaroline fosamil are needed to further support its use in pediatric patients. PMID:26766937

  18. Kinase Inhibitors that Increase the Sensitivity of Methicillin Resistant Staphylococcus aureus to β-Lactam Antibiotics

    Jay Vornhagen

    2015-10-01

    Full Text Available Staphylococcus aureus are Gram-positive bacteria that are the leading cause of recurrent infections in humans that include pneumonia, bacteremia, osteomyelitis, arthritis, endocarditis, and toxic shock syndrome. The emergence of methicillin resistant S. aureus strains (MRSA has imposed a significant concern in sustained measures of treatment against these infections. Recently, MRSA strains deficient in expression of a serine/threonine kinase (Stk1 or PknB were described to exhibit increased sensitivity to β-lactam antibiotics. In this study, we screened a library consisting of 280 drug-like, low-molecular-weight compounds with the ability to inhibit protein kinases for those that increased the sensitivity of wild-type MRSA to β-lactams and then evaluated their toxicity in mice. We report the identification of four kinase inhibitors, the sulfonamides ST085384, ST085404, ST085405, and ST085399 that increased sensitivity of WT MRSA to sub-lethal concentrations of β-lactams. Furthermore, these inhibitors lacked alerting structures commonly associated with toxic effects, and toxicity was not observed with ST085384 or ST085405 in vivo in a murine model. These results suggest that kinase inhibitors may be useful in therapeutic strategies against MRSA infections.

  19. Methicillin-Resistant Staphylococcus aureus Infections in Human Immunodeficiency Virus-Infected Children and Adolescents

    George K. Siberry

    2012-01-01

    Full Text Available Background. Methicillin-resistant Staphylococcus aureus (MRSA infection incidence has increased in healthy US children. Our objective was to evaluate MRSA incidence and correlates in HIV-infected youth. Methods. The CDC-sponsored LEGACY study is a US multicenter chart abstraction study of HIV-infected youth. We identified MRSA infections among participants with ≥1 visit during 2006. We used bivariate and multivariable analyses to compare sociodemographic and HIV clinical factors between MRSA cases and noncases. Results. Fourteen MRSA infections (1 invasive, 12 soft tissue, 1 indeterminate occurred among 1,813 subjects (11.1 infections/1,000 patient-years (PY, 95% CI: 11.06–11.14. Most (86% isolates were clindamycin susceptible. Compared with noncases, MRSA cases were more likely older (17 versus 14 years, black (100% versus 69%, behaviorally HIV infected (43% versus 17%, and in Maryland (43% versus 7% and had viral loads (VL >1000 copies/mL (86% versus 51% and lower mean CD4% (18% versus 27% (all P1000 copies/mL (aOR = 5.9, and black race (aOR undefined. Conclusions. MRSA occurred at a rate of 11.1 infections/1,000 PY in HIV-infected youth but invasive disease was uncommon. Geographic location, black race, and increased VL, but not immunosuppression, were independently associated with MRSA risk.

  20. Biofilm formation among methicillin-resistant Staphylococcus aureus isolates from patients with urinary tract infection.

    Ando E

    2004-08-01

    Full Text Available Staphylococci have been confirmed to form biofilms on various biomaterials. The purpose of this study was to investigate biofilm formation among methicillin-resistant Staphylococcus aureus (MRSA isolates from patients with urinary tract infection (UTI and to assess the relationship between biofilm-forming capacities and virulence determinants/clinical background. Over a 12-year period from 1990 through 2001, a total of 109 MRSA isolates were collected from patients (one isolate per patient with UTI at the urology ward of Okayama University Hospital. We used the in vitro microtiter plate assay to quantify biofilm formation. We then investigated the presence of several virulence determinants by polymerase chain reaction assay and found eight determinants (tst, sec, hla, hlb, fnbA, clfA, icaA, and agrII to be predominant among these isolates. Enhanced biofilm formation was confirmed in hla-, hlb-, and fnbA-positive MRSA isolates, both individually and in combination. Upon review of the associated medical records, we concluded that the biofilm-forming capacities of MRSA isolates from catheter-related cases were significantly greater than those from catheter-unrelated cases. The percentage of hla-, hlb-, and fnbA-positive isolates was higher among MRSA isolates from catheter-related cases than those from catheter-unrelated cases. Our studies suggest that MRSA colonization and infection of the urinary tract may be promoted by hla, hlb, and fnbA gene products.

  1. Antibacterial Activity of Rhus javanica against Methicillin-Resistant Staphylococcus aureus

    Yong-Ouk You

    2013-01-01

    Full Text Available In the present study, the leaves of Rhus javanica (R. javanica were extracted with ethanol, and we investigated the antimicrobial activity of the ethanol extract of R. javanica against methicillin-resistant Staphylococcus aureus (MRSA. Control groups were treated with media containing 0.1% DMSO. The ethanol extract of R. javanica inhibited the growth of MRSA at concentrations ranging from 0.05 to 0.2 mg/mL and inhibited acid production at concentrations higher than 0.1 mg/mL (P<0.05. MRSA biofilm formation was determined by scanning electron microscopy and safranin staining. The ethanol extract of R. javanica inhibited the formation of MRSA biofilms at concentrations higher than 0.05 mg/mL. In confocal laser scanning microscopy, high concentration (0.4–1.6 mg/mL of R. javanica extract showed bactericidal effect in a dose-dependent manner. In real-time PCR analysis, R. javanica extract showed the inhibition of the genetic expression of virulence factors such as mecA, sea, agrA, and sarA in MRSA. Preliminary phytochemical analysis revealed the strong presence of phenolics. These results suggest that R. javanica may be a useful medicinal plant for inhibiting MRSA, which may be related to the presence of phenolics in the R. javanica extract.

  2. Methicillin-resistant Staphylococcus aureus in commercial swine herds is associated with disinfectant and zinc usage.

    Slifierz, Mackenzie Jonathan; Friendship, Robert M; Weese, J Scott

    2015-04-01

    Methicillin-resistant Staphylococcus aureus (MRSA) originating from swine is concerning for public health, but an understanding of the emergence and persistence of MRSA in nursery herds is lacking. The aim of this study was to determine whether MRSA in nursery pigs is associated with particular herd-level parameters, including the use of antimicrobials, disinfectants, and heavy metals, which may be driving the selection and persistence of antimicrobial resistance. Nasal cultures for MRSA were completed for 390 pigs from 26 farms at the end of the suckling phase and again at 3 weeks postweaning. Herd-level information was collected, and a random subset of MRSA isolates was screened for resistance to zinc and quaternary ammonium compounds (QACs). Multivariate analysis revealed that in-feed concentrations of zinc (P commercial QAC exposure in the presence of organic matter. Overall, these findings indicate that high levels of in-feed zinc and QAC-based disinfectants are important drivers in the selection and persistence of MRSA in commercial swine herds, and these agents may be coselecting for other antimicrobial resistance genes. PMID:25662976

  3. PCR-based Approaches for the Detection of Clinical Methicillin-resistant Staphylococcus aureus

    Liu, Ying; Zhang, Jiang; Ji, Yinduo

    2016-01-01

    Staphylococcus aureus is an important pathogen that can cause a variety of infections, including superficial and systematic infections, in humans and animals. The persistent emergence of multidrug resistant S. aureus, particularly methicillin-resistant S. aureus, has caused dramatically economic burden and concerns in the public health due to limited options of treatment of MRSA infections. In order to make a correct choice of treatment for physicians and understand the prevalence of MRSA, it is extremely critical to precisely and timely diagnose the pathogen that induces a specific infection of patients and to reveal the antibiotic resistant profile of the pathogen. In this review, we outlined different PCR-based approaches that have been successfully utilized for the rapid detection of S. aureus, including MRSA and MSSA, directly from various clinical specimens. The sensitivity and specificity of detections were pointed out. Both advantages and disadvantages of listed approaches were discussed. Importantly, an alternative approach is necessary to further confirm the detection results from the molecular diagnostic assays. PMID:27335617

  4. Structure elucidation of anti-methicillin resistant Staphylococcus aureus (MRSA) flavonoids from balsam poplar buds.

    Simard, François; Gauthier, Charles; Legault, Jean; Lavoie, Serge; Mshvildadze, Vakhtang; Pichette, André

    2016-09-15

    There is nowadays an urgent need for developing novel generations of antibiotic agents due to the increased resistance of pathogenic bacteria. As a rich reservoir of structurally diverse compounds, plant species hold promise in this regard. Within this framework, we isolated a unique series of antibacterial flavonoids, named balsacones N-U, featuring multiple cinnamyl chains on the flavan skeleton. The structures of these compounds, isolated as racemates, were determined using extensive 1D and 2D NMR analysis in tandem with HRMS. Balsacones N-U along with previously isolated balsacones A-M were evaluated for their antibacterial activity against clinical isolates of methicillin resistant Staphylococcus aureus (MRSA). Several of the tested balsacones were potent anti-MRSA agents showing MIC values in the low micromolar range. Structure-activity relationships study highlighted some important parameters involved in the antibacterial activity of balsacones such as the presence of cinnamyl and cinnamoyl chains at the C-3 and C-8 positions of the flavan skeleton, respectively. These results suggest that balsacones could represent a potential novel class of naturally occurring anti-MRSA agents. PMID:27436809

  5. Nano-thick calcium oxide armed titanium: boosts bone cells against methicillin-resistant Staphylococcus aureus

    Cao, Huiliang; Qin, Hui; Zhao, Yaochao; Jin, Guodong; Lu, Tao; Meng, Fanhao; Zhang, Xianlong; Liu, Xuanyong

    2016-02-01

    Since the use of systemic antibiotics for preventing acute biomaterial-associated infections (BAIs) may build up bacterial resistance and result in huge medical costs and unpredictable mortality, new precaution strategies are required. Here, it demonstrated that titanium armed with a nano-thick calcium oxide layer was effective on averting methicillin-resistant Staphylococcus aureus (MRSA) infections in rabbits. The calcium oxide layer was constructed by, firstly, injecting of metallic calcium into titanium via a plasma immersion ion implantation process, and then transforming the outer most surface into oxide by exposing to the atmosphere. Although the calcium oxide armed titanium had a relative low reduction rate (~74%) in growth of MRSA in vitro, it could markedly promote the osteogenic differentiation of bone marrow stem cells (BMSCs), restore local bone integration against the challenge of MRSA, and decrease the incidence of MRSA infection with a rate of 100% (compared to the titanium control). This study demonstrated for the first time that calcium, as one of the major elements in a human body, could be engineered to avert MRSA infections, which is promising as a safe precaution of disinfection for implantable biomedical devices.

  6. Role of Berberine in the Treatment of Methicillin-Resistant Staphylococcus aureus Infections

    Chu, Ming; Zhang, Ming-Bo; Liu, Yan-Chen; Kang, Jia-Rui; Chu, Zheng-Yun; Yin, Kai-Lin; Ding, Ling-Yu; Ding, Ran; Xiao, Rong-Xin; Yin, Yi-Nan; Liu, Xiao-Yan; Wang, Yue-Dan

    2016-04-01

    Berberine is an isoquinoline alkaloid widely used in the treatment of microbial infections. Recent studies have shown that berberine can enhance the inhibitory efficacy of antibiotics against clinical multi-drug resistant isolates of methicillin-resistant Staphylococcus aureus (MRSA). However, the underlying mechanisms are poorly understood. Here, we demonstrated that sub-minimum inhibitory concentrations (MICs) of berberine exhibited no bactericidal activity against MRSA, but affected MRSA biofilm development in a dose dependent manner within the concentration ranging from 1 to 64 μg/mL. Further study indicated that berberine inhibited MRSA amyloid fibrils formation, which consist of phenol-soluble modulins (PSMs). Molecular dynamics simulation revealed that berberine could bind with the phenyl ring of Phe19 in PSMα2 through hydrophobic interaction. Collectively, berberine can inhibit MRSA biofilm formation via affecting PSMs’ aggregation into amyloid fibrils, and thereby enhance bactericidal activity of antibiotics. These findings will provide new insights into the multiple pharmacological properties of berberine in the treatment of microbial-generated amyloid involved diseases.

  7. Comparison of four diagnostic methods for detection of methicillin resistant Staphylococcus aureus.

    Mohammad Reza Pourmand

    2014-10-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA is a well-known pathogen with a worldwide distribution. Given the increasing rate of MRSA infections, implementing of reliable, accurate and rapid testing for diagnosis of MRSA is necessary. The aim of this study was to compare four diagnostic methods for detection of MRSA isolates.From December 2012 to April 2014, 120 S. aureus isolates were collected from three hospitals affiliated with Tehran University of Medical Sciences. MRSA isolates were detected by four different methods including cefoxitin disc diffusion test, oxacillin disc diffusion test, minimum inhibitory concentration (MIC of oxacillin as determined by MIC test strip, and mecA detection by PCR.Out of 120 S. aureus isolates, cefoxitin disc diffusion test, oxacillin disc diffusion test and MIC test strip identified 60 (50%, 48 (40%, 55 (45.83% isolates as MRSA, respectively. The sensitivity and specificity for oxacillin disc diffusion, cefoxitin disc diffusion and MIC of oxacillin were 80% and 100%, 100% and 100%, and 91.6% and 100%, respectively.Cefoxitin disc diffusion test is reliable substitute for detection of MRSA in clinical laboratory where MIC detection and molecular methods are not accessible.

  8. Methicillin-resistant Staphylococcus aureus mandibular osteomyelitis in an extremely low birth weight preterm infant.

    Martini, Silvia; Tumietto, Fabio; Sciutti, Rita; Greco, Laura; Faldella, Giacomo; Corvaglia, Luigi

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an established nosocomial pathogen with frequent multidrug resistance. The immaturity of the immune system along with intravascular lines and empirical antibiotic treatments place hospitalized preterm infants at major risk of MRSA infection.We report a case of MRSA mandibular osteomyelitis complicating a persistent S. aureus bacteremia in a 23-week preterm infant. From the first weeks of life, the infant showed recurrent C-reactive protein (CRP) elevation, associated with S. aureus bacteremia. Antibiotic courses, including vancomycin and linezolid, were performed with transitory normalization of blood parameters. On day 74, the infant suddenly deteriorated and showed a significant increase of both CRP and procalcitonin. Empiric vancomycin and piperacillin-tazobactam treatment was started; nevertheless, she developed a progressive hard swelling of neck and mandible. Radiological evaluation revealed a mandibular osteomyelitis complicated by an abscess, whose culture grew MRSA. Vancomycin was thus changed to teicoplanin and complete clinical and radiological healing was gradually achieved.In the presence of major risk factors, persistent bacteremia and nonspecific symptoms, a localized focus of infection should be suspected. Microbiological diagnosis should always be attempted and antibiotic treatment should be guided by both susceptibility results and clinical response. PMID:26239708

  9. Evidence based approach to the treatment of community-associated methicillin-resistant Staphylococcus aureus.

    Peppard, William J; Daniels, Anne; Fehrenbacher, Lynne; Winner, Jamie

    2009-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have increased dramatically over the last two decades. The types of infections can range from complicated skin and skin structure infections (cSSSI) to pneumonia and endocarditis. Oral antimicrobial therapy, such as trimethoprim-sulfamethoxazole, clindamycin, long-acting tetracyclines, or linezolid may provide enhanced benefit to those with uncomplicated cutaneous lesions when used in conjunction with incision and drainage in an outpatient setting. However, resistance, susceptibilities, patient-specific circumstances, and adverse effects can impact a healthcare professional's choice of antibiotics. In patients with complicated infections requiring hospitalization or parenteral treatment, vancomycin remains the drug of choice, even though increased resistance and decreased efficacy have crept into clinical practice. Linezolid, quinupristin/dalfopristin, daptomycin, and tigecycline are alternative intravenous agents for the treatment of CA-MRSA. Investigational agents such as dalbavancin, telavancin, oritivancin, iclaprim, ceftobiprole, ceftaroline, and others may expand our therapeutic armamentarium for the treatment of infections caused by CA-MRSA in the future. PMID:21694885

  10. Evolution and diversity of community-associated methicillin-resistant Staphylococcus aureus in a geographical region

    Ehricht Ralf

    2011-09-01

    Full Text Available Abstract Background Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA was first reported in remote regions of Western Australia and is now the predominant MRSA isolated in the state. The objective of this study is to determine the genetic relatedness of Western Australian CA-MRSA clones within different multilocus sequence type (MLST clonal clusters providing an insight into the frequency of S. aureus SCCmec acquisition within a region. Results The CA-MRSA population in Western Australia is genetically diverse consisting of 83 unique pulsed-field gel electrophoresis strains from which 46 MLSTs have been characterised. Forty five of these sequence types are from 18 MLST clonal clusters and two singletons. While SCCmec IV and V are the predominant SCCmec elements, SCCmec VIII and several novel and composite SCCmec elements are present. The emergence of MRSA in diverse S. aureus clonal clusters suggests horizontal transmission of the SCCmec element has occurred on multiple occasions. Furthermore DNA microarray and spa typing suggests horizontal transfer of SCCmec elements has also occurred within the same CC. For many single and double locus variant CA-MRSA clones only a few isolates have been detected. Conclusions Although multiple CA-MRSA clones have evolved in the Western Australian community only three clones have successfully adapted to the Western Australian community environment. These data suggest the successful evolution of a CA-MRSA clone may not only depend on the mobility of the SCCmec element but also on other genetic determinants.

  11. Molecular Epidemiology of Methicillin-Resistant Staphylococcus aureus Isolated from Australian Veterinarians.

    Groves, Mitchell D; Crouch, Bethany; Coombs, Geoffrey W; Jordan, David; Pang, Stanley; Barton, Mary D; Giffard, Phil; Abraham, Sam; Trott, Darren J

    2016-01-01

    This work investigated the molecular epidemiology and antimicrobial resistance of methicillin-resistant Staphylococcus aureus (MRSA) isolated from veterinarians in Australia in 2009. The collection (n = 44) was subjected to extensive molecular typing (MLST, spa, SCCmec, dru, PFGE, virulence and antimicrobial resistance genotyping) and antimicrobial resistance phenotyping by disk diffusion. MRSA was isolated from Australian veterinarians representing various occupational emphases. The isolate collection was dominated by MRSA strains belonging to clonal complex (CC) 8 and multilocus sequence type (ST) 22. CC8 MRSA (ST8-IV [2B], spa t064; and ST612-IV [2B], spa variable,) were strongly associated with equine practice veterinarians (OR = 17.5, 95% CI = 3.3-92.5, P < 0.001) and were often resistant to gentamicin and rifampicin. ST22-IV [2B], spa variable, were strongly associated with companion animal practice veterinarians (OR = 52.5, 95% CI = 5.2-532.7, P < 0.001) and were resistant to ciprofloxacin. A single pig practice veterinarian carried ST398-V [5C2], spa t1451. Equine practice and companion animal practice veterinarians frequently carried multiresistant-CC8 and ST22 MRSA, respectively, whereas only a single swine specialist carried MRSA ST398. The presence of these strains in veterinarians may be associated with specific antimicrobial administration practices in each animal species. PMID:26735694

  12. Sub-acute mastitis associated with Methicillin Resistant Staphylococcus aureus in a cow: A case report

    Duraisamy Chandrasekaran

    2014-12-01

    Full Text Available A 5-year old Holstein Friesian cross breed cow was presented to Madras Veterinary College Teaching Hospital with the history of reduced milk yield. Clinical examination of udder revealed normal milk color and soft udder. The milk pH was 7.0, with California Mastitis Test score 3+, Electrical Conductivity 270U, and Somatic Cell Count as 328,000. Isolation and identification of causative agent revealed Methicillin Resistant Staphylococcus aureus (MRSA from the sub-acute mastitis sample. Agar disc diffusion method for antimicrobial susceptibility revealed that the MRSA was sensitive to Enrofloxacin, Gentamicin, Oxytetracycline and Amoxicillin+Sulbactam. On the other hand, the isolate was resistance to Amoxicillin, Penicillin G, Ceftriaxone and Methicillin. The isolate was positive for β-lactamase resistance by Nitrocefin test. The MRSA was confirmed for the presence of mecA and blaZ target genes by polymerase chain reaction (PCR. The cow was treated with Enrofloxacin, Vitamin E and inorganic Selenium, and was recovered after 5 days of post-treatment.

  13. A case of methicillin-resistant Staphylococcus aureus infection following bile duct stenting

    Markus K Diener; Alexis Ulrich; Theresia Weber; Moritz N Wente; Markus W Büchler; Helmut Friess

    2005-01-01

    AIM: To present a case of methicillin-resistant Staphylococcus aureus (MRSA) infection following bile duct stenting in a patient with malignant biliary obstruction.METHODS: A 78-year-old male patient was admitted to a community hospital with progredient painless jaundice lasting over two weeks, weight loss and sweating at night.Whether a stent should be implanted pre-operatively in jaundiced patients or whether these patients should directly undergo surgical resection, was discussed.RESULTS: ERC and a biopsy from the papilla of Vater revealed an adenocarcinoma. In addition, a 7-Ch plastic stent was placed into the common bile duct. Persistent abdominal pain, increasing jaundice, weakness and indigestion led to the transfer of the patient to our hospital.A pylorus-preserving pancreatoduodenectomy wasperformed. Intraoperatively, bile leaked out of the transected choledochus andthe stent was found to be dislocated in the duodenum. A smear of the bile revealed an infection with MRSA, leading to post-operative isolation of the patient.CONCLUSION:As biliary stents can cause severe infection of the bile, the need for pre-operative placement of biliary stents should be carefully evaluated in each individual case.

  14. Resistance of canine methicillin-resistant Staphylococcus pseudintermedius strains to pradofloxacin.

    Kizerwetter-Świda, Magdalena; Chrobak-Chmiel, Dorota; Rzewuska, Magdalena; Binek, Marian

    2016-09-01

    We investigated in vitro activity of a novel veterinary fluoroquinolone, pradofloxacin, against methicillin-resistant Staphylococcus pseudintermedius (MRSP) isolates and compared with other fluoroquinolones. A total of 38 MRSP isolates were subjected to agar disk diffusion tests for sensitivity to pradofloxacin, orbifloxacin, marbofloxacin, enrofloxacin, and ciprofloxacin. The minimal inhibitory concentration (MIC) values of pradofloxacin, ciprofloxacin, and enrofloxacin were determined. Mutations in the genes encoding DNA gyrase subunit A (GyrA) and topoisomerase IV (GrlA) proteins associated with fluoroquinolone resistance were studied by an analysis of partial sequences of the genes encoding these proteins. Two MRSP isolates were susceptible in disk diffusion and microdilution test to all fluoroquinolones tested, including pradofloxacin. Based on the results of the disk diffusion testing, 33 of 38 isolates showed resistance to pradofloxacin and 3 were intermediate, whereas, by pradofloxacin MIC testing, 35 isolates were classified as resistant and 1 as intermediate. Single alterations in GyrA and GrlA proteins were observed in the 35 resistant isolates and the 1 intermediate isolate (MIC results). These same 36 isolates were also resistant to the other tested fluoroquinolones. The results of the current study showed that MRSP isolates are usually resistant to all fluoroquinolones, including pradofloxacin. Therefore, in routine susceptibility testing to pradofloxacin by disk diffusion, the results should be carefully interpreted for MRSP isolates, especially those resistant to other fluoroquinolones and, in questionable cases, the pradofloxacin MIC should be determined to confirm the susceptibility testing results. PMID:27449131

  15. A field guide to pandemic, epidemic and sporadic clones of methicillin-resistant Staphylococcus aureus.

    Monecke, Stefan

    2011-04-01

    In recent years, methicillin-resistant Staphylococcus aureus (MRSA) have become a truly global challenge. In addition to the long-known healthcare-associated clones, novel strains have also emerged outside of the hospital settings, in the community as well as in livestock. The emergence and spread of virulent clones expressing Panton-Valentine leukocidin (PVL) is an additional cause for concern. In order to provide an overview of pandemic, epidemic and sporadic strains, more than 3,000 clinical and veterinary isolates of MRSA mainly from Germany, the United Kingdom, Ireland, France, Malta, Abu Dhabi, Hong Kong, Australia, Trinidad & Tobago as well as some reference strains from the United States have been genotyped by DNA microarray analysis. This technique allowed the assignment of the MRSA isolates to 34 distinct lineages which can be clearly defined based on non-mobile genes. The results were in accordance with data from multilocus sequence typing. More than 100 different strains were distinguished based on affiliation to these lineages, SCCmec type and the presence or absence of PVL. These strains are described here mainly with regard to clinically relevant antimicrobial resistance- and virulence-associated markers, but also in relation to epidemiology and geographic distribution. The findings of the study show a high level of biodiversity among MRSA, especially among strains harbouring SCCmec IV and V elements. The data also indicate a high rate of genetic recombination in MRSA involving SCC elements, bacteriophages or other mobile genetic elements and large-scale chromosomal replacements.

  16. The Antibacterial Assay of Tectorigenin with Detergents or ATPase Inhibitors against Methicillin-Resistant Staphylococcus aureus

    Dae-Ki Joung

    2014-01-01

    Full Text Available Tectorigenin (TTR is an O-methylated isoflavone derived from the rhizome of Belamacanda chinensis (L. DC. It is known to perform a wide spectrum of biological activities such as antioxidant, anti-inflammatory, anti-tumor. The aim of this study is to examine the mechanism of antibacterial activity of TTR against methicillin-resistant Staphylococcus aureus (MRSA. The anti-MRSA activity of TTR was analyzed in combination assays with detergent, ATPase inhibitors, and peptidoglycan (PGN derived from S. aureus. Transmission electron microscopy (TEM was used to monitor survival characteristics and changes in S. aureus morphology. The MIC values of TTR against all the tested strains were 125 μg/mL. The OD(600 of each suspension treated with a combination of Triton X-100, DCCD, and NaN3 with TTR (1/10 × MIC had been reduced from 68% to 80%, compared to the TTR alone. At a concentration of 125 μg/mL, PGN blocked antibacterial activity of TTR. This study indicates that anti-MRSA action of TTR is closely related to cytoplasmic membrane permeability and ABC transporter, and PGN at 125 μg/mL directly bind to and inhibit TTR at 62.5 μg/mL. These results can be important indication in study on antimicrobial activity mechanism against multidrug resistant strains.

  17. Atomic force microscopy study of the antibacterial effect of fosfomycin on methicillin-resistant Staphylococcus pseudintermedius

    Neethirajan, Suresh; DiCicco, Matthew

    2014-08-01

    The influence of fosfomycin on methicillin-resistant Staphylococcus pseudintermedius (MRSP) as the target cell was studied by atomic force microscopy (AFM). Nanoscale images of the effects of the antibiotic fosfomycin on this gram-positive bacterium's cell were obtained in situ without fixing agents. Our study has demonstrated substantial morphological and topographical differences between the control and fosfomycin-treated MRSP cells. The AFM investigations further revealed the rough surface morphology and a 30 % shrinkage in size of the fosfomycin-treated cell and the leakage of cytoplasmic components from the cell. The damage of cell membrane integrity and the cell surface degradation as observed elaborates the antibacterial activity of fosfomycin. The AFM image analysis also reveals that the fosfomycin inhibits cell division, and prevents the adhesion on the surface discouraging the biofilm attachment. The micro-titre plate assay results conform to the atomic force microscopy image analysis. This is the first visual demonstration of the effect of fosfomycin on MRSP cells.

  18. Efficacy of combined vancomycin and fosfomycin against methicillin-resistant Staphylococcus aureus in biofilms in vivo.

    Jian Shi

    Full Text Available Infection by methicillin-resistant Staphylococcus aureus (MRSA is a life-threatening condition, and formation of biofilms can lead to treatment failure in a clinical setting. The aim of this study was to demonstrate the in vivo bactericidal effects of a combination of vancomycin (VAN and fosfomycin (FOS against MRSA in a rat carboxymethyl cellulose-pouch biofilm model. The results of the time-kill assay showed that the combination therapy was capable of killing at low minimal inhibitory concentrations (MIC (½ × MIC VAN +1 × MIC FOS and 1 × MIC VAN + 1 × MIC FOS. In the in vivo study, a synergistically bactericidal effect was observed when using the combination therapy on MRSA embedded in the mature biofilm model. In comparison with the untreated control group and the groups receiving either VAN or FOS alone, the rats treated with combination therapy had lower MRSA colony counts in exudates from the pouch, lower white blood cell and neutrophil counts, and C-reactive protein (CRP in peripheral blood. Furthermore, histological analysis of the pouch wall indicated combination therapy resulted in disappearance of biofilm-like structures, marked decrease in necrosis, and formation of granular tissue. In conclusion, the combination of VAN with FOS had a synergistic bactericidal effect on chronic MRSA infection embedded in biofilm, providing an alternative approach to treating this condition.

  19. Kinase Inhibitors that Increase the Sensitivity of Methicillin Resistant Staphylococcus aureus to β-Lactam Antibiotics.

    Vornhagen, Jay; Burnside, Kellie; Whidbey, Christopher; Berry, Jessica; Qin, Xuan; Rajagopal, Lakshmi

    2015-01-01

    Staphylococcus aureus are Gram-positive bacteria that are the leading cause of recurrent infections in humans that include pneumonia, bacteremia, osteomyelitis, arthritis, endocarditis, and toxic shock syndrome. The emergence of methicillin resistant S. aureus strains (MRSA) has imposed a significant concern in sustained measures of treatment against these infections. Recently, MRSA strains deficient in expression of a serine/threonine kinase (Stk1 or PknB) were described to exhibit increased sensitivity to β-lactam antibiotics. In this study, we screened a library consisting of 280 drug-like, low-molecular-weight compounds with the ability to inhibit protein kinases for those that increased the sensitivity of wild-type MRSA to β-lactams and then evaluated their toxicity in mice. We report the identification of four kinase inhibitors, the sulfonamides ST085384, ST085404, ST085405, and ST085399 that increased sensitivity of WT MRSA to sub-lethal concentrations of β-lactams. Furthermore, these inhibitors lacked alerting structures commonly associated with toxic effects, and toxicity was not observed with ST085384 or ST085405 in vivo in a murine model. These results suggest that kinase inhibitors may be useful in therapeutic strategies against MRSA infections. PMID:26506394

  20. Empirical therapy in Methicillin-resistant Staphylococcus Aureus infections: An Up-To-Date approach.

    VanEperen, Alison S; Segreti, John

    2016-06-01

    Methicillin-resistant Staphylococcus aureus (MRSA) continues to be an important pathogen worldwide, with high prevalence of infection in both community and hospital settings. Timely and appropriate choice of empirical therapy in the setting of MRSA infection is imperative due to the high rate of associated morbidity and mortality with MRSA infections. Initial choices should be made based on the site and severity of the infection, most notably moderate skin and soft tissue infections which may be treated with oral antibiotics (trimethoprim-sulfamethoxazole, clindamycin, doxycycline/minocycline, linezolid) in the outpatient setting, versus choice of parenteral therapy in the inpatient setting of more invasive or severe disease. Though the current recommendations continue to strongly rely on vancomycin as a standard empiric choice in the setting of severe/invasive infections, alternative therapies exist with studies supporting their non-inferiority. This includes the use of linezolid in pneumonia and severe skin and skin structure infections (SSSI) and daptomycin for MRSA bacteremia, endocarditis, SSSIs and bone/joint infections. Additionally, concerns continue to arise in regards to vancomycin, such as increasing isolate MICs, and relatively high rates of clinical failures with vancomycin. Thus, the growing interest in vanomycin alternatives, such as ceftaroline, ceftobribole, dalbavancin, oritavancin, and tedizolid, and their potential role in treating MRSA infections. PMID:27066882

  1. Methicillin-Resistant Staphylococcus aureus Keratitis after Descemet's Stripping Automated Endothelial Keratoplasty

    Tatsuro Miyamoto

    2013-11-01

    Full Text Available Purpose: We report a case of methicillin-resistant Staphylococcus aureus (MRSA keratitis after Descemet's stripping automated endothelial keratoplasty (DSAEK. Case Report: An 87-year-old woman who had undergone a DSAEK 4 months previously was referred to Tokushima University Hospital with a diagnosis of infectious keratitis after DSAEK. A white abscess and infiltration in the inferior cornea of the right eye were observed. We started an empiric therapy using topical levofloxacin and chloramphenicol on the basis of the microscopic findings of the corneal scraping concurrently with cultivation of the cornea. Results: A strain of MRSA was isolated from the corneal sample. Although the strain was susceptible to chloramphenicol, it was resistant to quinolone. The keratitis improved rapidly due to empiric therapy, and topical steroids could be resumed 6 days after initiation of the empiric therapy. Conclusions: To our knowledge, this is the first case of MRSA keratitis, and the second case of bacterial keratitis, after DSAEK. MRSA keratitis can occur following uneventful DSAEK. The empiric therapy on the basis of results from a light microscopic examination of a Gram-stained corneal scraping and restarting topical steroids in the early stages of medication contributed to the good clinical course of this case.

  2. Methicillin-resistant Staphylococcus aureus ST9 in pigs in Thailand.

    Jesper Larsen

    Full Text Available BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA is an important nosocomial and community-associated pathogen. Recently, livestock-associated MRSA (LA-MRSA has emerged and disseminated in Europe and North America and now constitutes a considerable zoonotic burden in humans with risk factors of pig exposure, whereas the extent of the livestock reservoir is relatively unknown on other continents. METHODOLOGY/PRINCIPAL FINDINGS: From March through April 2011, MRSA was identified in pigs from 3 out of 30 production holdings in Chang Mai Province, Thailand. Representative isolates were subjected to molecular characterization and antimicrobial susceptibility testing; all isolates had genotypic and phenotypic characteristics of LA-MRSA previously characterized in the region: they belonged to ST9, lacked the lukF-lukS genes encoding Panton-Valentine leukocidin, and were resistant to multiple non-β-lactam antimicrobials. However, unlike other Asian LA-MRSA-ST9 variants, they were spa type t337 and harbored a different staphylococcal cassette chromosome mec IX. CONCLUSIONS/SIGNIFICANCE: A novel MRSA-ST9 lineage has been established in the pig population of Thailand, which differs substantially from LA-MRSA lineages found in other areas of the continent. The emergence of novel LA-MRSA lineages in the animal agriculture setting is worrisome and poses a serious threat to global public health.

  3. Do guidelines for the prevention and control of methicillin-resistant Staphylococcus aureus make a difference?

    Humphreys, H

    2009-12-01

    Many countries have national guidelines for the prevention and control of methicillin-resistant Staphylococcus aureus (MRSA) that are similar in approach. The evidence base for many recommendations is variable, and often, in the drafting of such guidelines, the evidence is either not analysed or not specifically reviewed. Guidelines usually recommend screening and early detection, hand hygiene, patient isolation or cohorting, and decolonization. Although many components of a prevention and control programme appear to be self-evident, e.g. patient isolation, the scientific base underpinning these is poor, and scientifically rigorous studies are required. Nonetheless, where measures, based on what evidence there is and on common sense, are implemented, and where the necessary resources are provided, MRSA can be controlled. In The Netherlands and in other low-prevalence countries, these measures have largely kept healthcare facilities MRSA-free. In MRSA-endemic countries, such as Spain and Ireland, national guidelines are often not fully implemented, owing to apparently inadequate resources or a lack of will. However, recent studies from France and Australia demonstrate what is possible in high-prevalence countries when best practice is effectively implemented, with potentially major benefits for patients, the respective health services, and society.

  4. Methicillin resistant Staphylococcus aureus nasal colonization among secondary school students at Duhok City-Iraq

    Ary Habeeb

    2014-06-01

    Full Text Available Objective:Methicillin-resistant Staphylococcus aureus (MRSA widely distributed in hospitals around the world. There is strong relationship between disease development and S. aureus nasal carriage. The aim of this study was to evaluate the prevalence and epidemiology of nasal colonization with S. aureus and MRSA in the community of Duhok city, Iraq. Methods: 489 students aged 16 to18 years were included. Nasal swab samples were collected followed by antimicrobial susceptibility test. MRSA isolates were selected and investigated for the mecA gene. Also the prevalence of PantonValentine Leukocidin (PVL gene was also studied. Results: A total of 90 (18.4% out of 489 (18.4% of the students were found to be colonized by S. aureus . Only 10 (2.04% of the students were found to be MRSA carrier. All MRSA isolates were sensitive to Vancomycin. PLV gene was detected in one MRSA strain. Conclusion: This is the first study investigating S. aureus colonization in students in the Duhok city. Nasal carriage of S. aureus and MRSA is comparable with reports from elsewhere. Fortunately, all trains included in our study were sensitive to vancomycin. Further research is needed to examine the SCCmec elements and the evolution of MRSA over the time. J Microbiol Infect Dis 2014;4(2: 59-63

  5. Methicillin-resistant Staphylococcus aureus: risk factors associated with community-onset infections in Denmark

    Böcher, Sidsel; Gervelmeyer, Andrea; Monnet, Dominique;

    2008-01-01

    The proportion of methicillin-resistant Staphylococcus aureus (MRSA) in Denmark has been below 1% for more than 30 years. However, a marked increase in community-onset MRSA (CO-MRSA) started in 2002. To identify possible risk factors for CO-MRSA infections, a nationwide case-control study...... was conducted in 2004. Cases (34) were patients with CO-MRSA infections; controls (87) were patients with community-onset methicillin-sensitive S. aureus infections (CO-MSSA). Demographic and clinical data and exposures to possible risk factors during the last 24 months were collected with a structured...... hospitalization for >7 days within the previous 6 months tended to be associated with CO-MRSA infection (OR 5.7, 95% CI 0.9-36.4). The predominant MRSA clones found in this study were CC80 (26%), CC8 (24%) and CC5 (18%). Resistance to three or more antimicrobial drug classes was seen in 47% of CO-MRSA isolates...

  6. Heavy metal and disinfectant resistance genes among livestock-associated methicillin-resistant Staphylococcus aureus isolates

    Argudin, Maria Angeles; Lauzat, Birgit; Kraushaar, Britta;

    2016-01-01

    substances with antimicrobial activity applied in animal feed, including metal-containing compounds might contribute to their selection. Some of these genes have been found in various novel SCCmec cassettes. The aim of this study was to assess the occurrence of metal-resistance genes among a LA-S. aureus...... collection [n = 554, including 542 MRSA and 12 methicillin-susceptible S. aureus (MSSA)] isolated from livestock and food thereof. Most LA-MRSA isolates (76%) carried at least one metal-resistance gene. Among the LA-MRSA CC398 isolates (n = 456), 4.8%, 0.2%, 24.3% and 71.5% were positive for arsA (arsenic......Livestock associated methicillin-resistant Staphylococcus aureus (LA-MRSA) has emerged in animal production worldwide. Most LA-MRSA in Europe belong to the clonal complex (CC)398. The reason for the LA-MRSA emergence is not fully understood. Besides antimicrobial agents used for therapy, other...

  7. Inhibitory Effect Evaluation of Glycerol-Iron Oxide Thin Films on Methicillin-Resistant Staphylococcus aureus

    C. L. Popa

    2015-01-01

    Full Text Available The main purpose of this study was to evaluate the inhibitory effect of glycerol- iron oxide thin films on Methicillin-Resistant Staphylococcus aureus (MRSA. Our results suggest that glycerol-iron oxide thin films could be used in the future for various biomedical and pharmaceutical applications. The glycerol-iron oxide thin films have been deposited by spin coating method on a silicon (111 substrate. The structural properties have been studied by X-ray diffraction (XRD and scanning electron spectroscopy (SEM. The XRD investigations of the prepared thin films demonstrate that the crystal structure of glycerol-iron oxide nanoparticles was not changed after spin coating deposition. On the other hand, the SEM micrographs suggest that the size of the glycerol-iron oxide microspheres increased with the increase of glycerol exhibiting narrow size distributions. The qualitative depth profile of glycerol-iron oxide thin films was identified by glow discharge optical emission spectroscopy (GDOES. The GDOES spectra revealed the presence of the main elements: Fe, O, C, H, and Si. The antimicrobial activity of glycerol-iron oxide thin films was evaluated by measuring the zone of inhibition. After 18 hours of incubation at 37°C, the diameters of the zones of complete inhibition have been measured obtaining values around 25 mm.

  8. The Frequency of Methicillin-Resistant Staphylococcus aureus and Coagulase Gene Polymorphism in Egypt

    Hend M. Abdulghany

    2014-01-01

    Full Text Available The current study aimed to use Coagulase gene polymorphism to identify methicillin-resistant Staphylococcus aureus (MRSA subtypes isolated from nasal carriers in Minia governorate, Egypt, evaluate the efficiency of these methods in discriminating variable strains, and compare these subtypes with antibiotypes. A total of 400 specimens were collected from nasal carriers in Minia governorate, Egypt, between March 2012 and April 2013. Fifty-eight strains (14.5% were isolated and identified by standard microbiological methods as MRSA. The identified isolates were tested by Coagulase gene RFLP typing. Out of 58 MRSA isolates 15 coa types were classified, and the amplification products showed multiple bands (1, 2, 3, 4, 5, and 8 bands. Coagulase gene PCR-RFLPs exhibited 10 patterns that ranged from 1 to 8 fragments with AluI digestion. Antimicrobial susceptibility testing with a panel of 8 antimicrobial agents showed 6 different antibiotypes. Antibiotype 1 was the most common phenotype with 82.7%. The results have demonstrated that many new variants of the coa gene are present in Minia, Egypt, different from those reported in the previous studies. So surveillance of MRSA should be continued.

  9. Tolerability of a probiotic in subjects with a history of methicillin-resistant Staphylococcus aureus colonisation.

    Warrack, S; Panjikar, P; Duster, M; Safdar, N

    2014-12-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen of major public health importance. Colonisation precedes infection; thus reducing MRSA carriage may be of benefit for reducing infection. Probiotics represent a novel approach to reducing MRSA carriage. We undertook a pilot feasibility randomised controlled trial of the tolerability and acceptability of probiotics for reducing nasal and intestinal carriage of MRSA. In addition, subjects were screened for vancomycin-resistant enterocococci (VRE). Subjects with a history of MRSA were recruited from a large, academic medical center and randomised to take either a placebo or probiotic (Lactobacillus rhamnosus HN001). Subjects returned to the clinic after four weeks for further testing to determine adherence to the probiotic regimen and colonisation of MRSA. 48 subjects were enrolled and randomised. Nearly 25% were transplant recipients and 30% had diabetes. The probiotic was well tolerated in the study population though minor side effects, such as nausea and bloating, were observed. A majority of the subjects randomised to HN001 had good adherence to the regimen. At the four week time point among subjects randomised to the probiotic, MRSA was detected in 67 and 50% of subjects colonised in the nares and the gastrointestinal tract, respectively. Three subjects who initially tested positive for VRE were negative after four weeks of probiotic exposure. Probiotics were well tolerated in our study population of largely immunocompromised subjects with multiple comorbidities. Adherence to the intervention was good. Probiotics should be studied further for their potential to reduce colonisation by multidrug resistant bacteria. PMID:25213147

  10. Detection of Genes for Superantigen Toxins in Methicillin-Resistant Staphylococcus aureus Clinical Isolates in Karachi

    Objective: To detect genes for enterotoxins, exfoliative and toxic shock syndrome toxins in Staphylococcus aureus (S. aureus) strains isolated from clinical specimens. Study Design: Cross-sectional observational study. Place and Duration of Study: Department of Molecular Genetics, Dr. Ziauddin Hospital, Karachi, from January to December 2010. Methodology: Two hundred and ninety eight S. aureus clinical isolates were obtained from various clinical samples received at Dr. Ziauddin Hospital, Karachi. Out of these, 115 were detected as methicillin resistant (MRSA) by cefoxitin disk diffusion test showing a prevalence rate of 38.6%. Detection of individual toxin genes was performed by Polymerase Chain Reaction (PCR) by using only one primer pair for each tube. Uniplex primers were preferred as multiplex primers are longer in base pairs and have the potential for cross reaction due to non-specific binding and increase in optimization time. Results: The possession of a single gene or more than a single gene in MRSA isolates was found in 61.73% of clinical samples; the highest number was found in pus swab, followed by sputum, blood, urethral swab, and urine. The prevalence of toxin genes was higher in MRSA as compared to methicillin sensitive (MSSA) isolates (19.12%). Conclusion: PCR detects strains possessing toxin genes independent of their expression. The possession of genes for super-antigens seems to be a frequent and habitual trait of S. aureus more so in MRSA. (author)

  11. Activity of the Extracts and Neolignans from Piper regnellii against Methicillin-Resistant Staphylococcus aureus (MRSA

    Benedito Prado Dias Filho

    2010-03-01

    Full Text Available Piper regnellii (Miq. C. DC. var. pallescens (C. DC. Yunck (Piperaceae is a medicinal plant traditionally used in Brazil to treat infectious diseases. The extracts obtained of the leaves from P. regnellii were investigated for their antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA. The ethyl acetate extract presented a good activity against MRSA, with minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC of 16 μg/mL. Based on this finding, the ethyl acetate extract was fractionated by silica gel column chromatography into nine fractions. The hexane fraction was active against MRSA (MIC at 4 μg/mL. Further column chromatography separation of the hexane fraction afforded the pure compound eupomatenoid-5. The structure of the compound was established by spectral data (1H and 13C NMR HSQC, HMBC, gNOE, IR and MS. Eupomatenoid-5 was the only compound active on the bacterium. The antibacterial property of P. regnellii extract provides preliminary scientific validation for the traditional medicinal use of this plant. The active compound eupomatenoid-5 should be further studied in animal models to verify in vivo efficacy and toxicity.

  12. The presence of methicillin-resistant Staphylococcus aureus on large pig breeding farms in Croatia.

    Habrun, Boris; Račić, Ivana; Beck, Relja; Budimir, Ana; Benić, Miroslav; Kompes, Gordan; Spičić, Silvio; Cvetnić, Zeljko

    2011-12-01

    Methicillin-resistant Staphylococcus aureus (MRSA) have emerged worldwide and have become resistant to a variety of antibiotics. MRSA colonisation in pigs was first reported from the Netherlands in 2005, where pigs were implicated as a source of human MRSA infections (Voss et al., 2005). This paper presents the first report on the presence of MRSA on large pig breeding farms in Croatia, together with the determination of the mecA gene, the results of spa typing and susceptibility to commonly used antimicrobials. Dust samples (7-11 per farm) were collected from eight large pig farms in Croatia. Of the total 68 swabs, the mecA gene was detected in 24 isolates growing on the MRSA agar. All isolates were resistant to oxacillin, tetracycline and streptomycin, and susceptible only to vancomycin, while 92% of the strains were susceptible to ciprofloxacin. Genotyping of the MRSA strains was performed by spa typing, and revealed t011 (n = 17), t034 (n = 5) and t1451 (n = 2). The results presented here predict that MRSA is present on a large number of pig farms in Croatia. PMID:22079702

  13. The molecular changing mechanism of Ampicillin-Sulbactam resistant Staphylococcus aureus towards Methicillin resistant Staphylococcus aureus

    Mieke Hemiawati Satari

    2005-12-01

    Full Text Available The aim of this study was to determine the molecular changing of S.aureus, which is resistant to Ampicillin-Sulbactam and then become resistant to Methicillin as a result of improper dosage. The study was conducted by isolating Ampicillin-Sulbactam resistant and Methicillin Resistant S.aureus (MRSA, afterwards an amplification process was performed by PCR (Polymerase Chain Reaction. to isolate the betalactamase enzyme regulator and PBP 2a genes. The result of this research showed that there were a deletion of few amino acids from the regulator gene, and a suspicion that the DNA sequence had been substituted from PBP 2 gene into PBP 2a (gen mec. This process had formed MRSA.

  14. SCCmec Typing of Methicillin-Resistant Staphylococcus aureus: An Eight Year Experience

    Fateh Amirkhiz

    2015-10-01

    Full Text Available Background Methicillin resistant Staphylococcus aureus strains (MRSA are important pathogens that cause serious diseases in humans. Throughout the recent years, the spread of these strains has increased in medical environments and society, and has become a serious challenge in health systems. Therefore, it is vital to investigate the various MRSA types to identify the origins of the infections and to control the spread of these infections in hospitals. Objectives The current study aimed to evaluate the different SCCmec types in MRSA isolates from hospitals of Tabriz, by staphylococcal cassette chromosome mec (SCCmec typing. Materials and Methods The present descriptive and retrospective study was performed on 151 selected S. aureus isolates obtained from clinical specimens who were referred to Tabriz university of medical sciences educational-health care centers from April 2005 to September 2012. MRSA isolates were identified by agar disk diffusion and mecA PCR assays. Ultimately, they were typified according to the genetic diversity of the chromosome cassette of SCCmec and ccr regions. Results Of the 151 isolates, 53 were recognized as MRSA. All of these 53 samples were sensitive to teicoplanin and vancomycin. Antibiotic resistance patterns were as follows: azithromycin 56.6%, ciprofloxacin 28.3%, imipenem 11.3%, meropenem 9.4%, ofloxacin 13.2%, ceftriaxone 66%, cotrimoxazole 49.1%, gentamicin 52.8%, linezolid 11.3%, penicillin 90.6%, and rifampicin 5.7%. The majority of MRSA isolates belonged to SCCmec III (69.8% followed by SCCmec IVc (7.5%, SCCmec IVa (3.8%, and SCCmec I (1.9%. Other types of SCCmec were not observed in the present study. Moreover, from the 53 MRSA samples, 9 were recognized as non-typable. However, staphylococcal cassette chromosome recombinase (ccr genetic complex analysis revealed that among the 53 studied samples, 4 isolates had ccr type 1 pattern, and 11 and 32 isolates had ccr type 2 and ccr type 3 pattern

  15. Graphene oxide-silver nanocomposite as a promising biocidal agent against methicillin-resistant Staphylococcus aureus

    de Moraes ACM

    2015-11-01

    Full Text Available Ana Carolina Mazarin de Moraes,1 Bruna Araujo Lima,2 Andreia Fonseca de Faria,1 Marcelo Brocchi,2 Oswaldo Luiz Alves1 1Laboratory of Solid State Chemistry, Institute of Chemistry, University of Campinas, Campinas, São Paulo, Brazil; 2Department of Genetics, Evolution and Bioagents, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil Background: Methicillin-resistant Staphylococcus aureus (MRSA has been responsible for serious hospital infections worldwide. Nanomaterials are an alternative to conventional antibiotic compounds, because bacteria are unlikely to develop microbial resistance against nanomaterials. In the past decade, graphene oxide (GO has emerged as a material that is often used to support and stabilize silver nanoparticles (AgNPs for the preparation of novel antibacterial nanocomposites. In this work, we report the synthesis of the graphene-oxide silver nanocomposite (GO-Ag and its antibacterial activity against relevant microorganisms in medicine. Materials and methods: GO-Ag nanocomposite was synthesized through the reduction of silver ions (Ag+ by sodium citrate in an aqueous GO dispersion, and was extensively characterized using ultraviolet-visible absorption spectroscopy, X-ray diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, and transmission electron microscopy. The antibacterial activity was evaluated by microdilution assays and time-kill experiments. The morphology of bacterial cells treated with GO-Ag was investigated via transmission electron microscopy. Results: AgNPs were well distributed throughout GO sheets, with an average size of 9.4±2.8 nm. The GO-Ag nanocomposite exhibited an excellent antibacterial activity against methicillin-resistant S. aureus, Acinetobacter baumannii, Enterococcus faecalis, and Escherichia coli. All (100% MRSA cells were inactivated after 4 hours of exposure to GO-Ag sheets. In addition, no toxicity was found for either pristine GO or bare Ag

  16. Rapid Detection of Methicillin-Resistant Staphylococcus aureus Directly from Sterile or Nonsterile Clinical Samples by a New Molecular Assay

    Francois, Patrice; Pittet, Didier; Bento, Manuela; Pepey, Béatrice; Vaudaux, Pierre; Lew, Daniel; Schrenzel, Jacques

    2003-01-01

    A rapid procedure was developed for detection and identification of methicillin-resistant Staphylococcus aureus (MRSA) directly from sterile sites or mixed flora samples (e.g., nose or inguinal swabs). After a rapid conditioning of samples, the method consists of two main steps: (i) immunomagnetic enrichment in S. aureus and (ii) amplification-detection profile on DNA extracts using multiplex quantitative PCR (5′-exonuclease qPCR, TaqMan). The triplex qPCR assay measures simultaneously the following targets: (i) mecA gene, conferring methicillin resistance, common to both S. aureus and Staphylococcus epidermidis; (ii) femA gene from S. aureus; and (iii) femA gene from S. epidermidis. This quantitative approach allows discrimination of the origin of the measured mecA signal. qPCR data were calibrated using two reference strains (MRSA and methicillin-resistant S. epidermidis) processed in parallel to clinical samples. This 96-well format assay allowed analysis of 30 swab samples per run and detection of the presence of MRSA with exquisite sensitivity compared to optimal culture-based techniques. The complete protocol may provide results in less than 6 h (while standard procedure needs 2 to 3 days), thus allowing prompt and cost-effective implementation of contact precautions. PMID:12517857

  17. Disorganization of cell division of methicillin-resistant Staphylococcus aureus by a component of tea (Camellia sinensis): a study by electron microscopy.

    Hamilton-Miller, J M; Shah, S

    1999-07-15

    A component of aqueous extracts of green tea (Camellia sinensis), known to reverse methicillin-resistance in staphylococci, causes extensive morphological changes in methicillin-resistant but not in methicillin-sensitive Staphylococcus aureus. Clumps of partly divided cocci, consisting of up to 14 individuals, with thickened internal but normal external cell walls were seen by electron microscopy in cultures of methicillin-resistant S. aureus grown in the presence of the active principle. The morphological changes observed were consistent with selective inhibition of penicillin-binding proteins. PMID:10427729

  18. Sternoclavicular septic arthritis due to methicillin-resistant Staphylococcus aureus in a patient with a suprapubic catheter.

    Monteiro, Nadine; Moleiro, Filipa; Lérias, Graça; Silva, Alberto Mello

    2015-01-01

    We report a case of a 74-year-old man who presented to the emergency department with a 1-week history of fever. He had a meatal stenosis and had a suprapubic catheter for 10 months, and had a recent hospitalisation for urosepsis with bacteraemia due to methicillin-resistant Staphylococcus aureus after manipulation of the catheter. Clinical examinations were performed in the emergency department and the patient was hospitalised with the diagnosis of recurrent urinary tract infection. The following day, we noticed the development of a mass in the left sternoclavicular joint with inflammatory signs and excruciating pain. Ultrasonographic findings led to the diagnosis of left sternoclavicular synovitis, and methicillin-resistant S. aureus grew in blood cultures leading to the diagnosis of sternoclavicular septic arthritis. Treatment with vancomycin and gentamicin was started and maintained for 4 weeks with complete resolution of symptoms and no complications or sequelae. PMID:25694643

  19. Partial Excision of the Chromosomal Cassette Containing the Methicillin Resistance Determinant Results in Methicillin-Susceptible Staphylococcus aureus

    Donnio, Pierre-Yves; Oliveira, Duarte C.; Faria, Nuno A.; Wilhelm, Nathalie; Le Coustumier, Alain; de Lencastre, Herminia

    2005-01-01

    We report a detailed characterization of methicillin-susceptible Staphylococcus aureus isolates from five French hospitals negative for both the mecA and the ccrAB loci but positive for the IS431::pUB110::IS431::dcs structure, present in some Staphylococcus cassette chromosome mec (SCCmec) types. The presence of SCCmec-associated elements suggests that this unusual resistant phenotype is due to a partial excision of SCCmec from epidemic methicillin-resistant S. aureus. The hypothesis of a genetic relatedness is strengthened by common sequence and spa types and similar susceptibility patterns. PMID:16081974

  20. Short communication: Prevalence of methicillin resistance in coagulase-negative staphylococci and Staphylococcus aureus isolated from bulk milk on organic and conventional dairy farms in the United States.

    Cicconi-Hogan, K M; Belomestnykh, N; Gamroth, M; Ruegg, P L; Tikofsky, L; Schukken, Y H

    2014-05-01

    The objective of this study was to evaluate the presence of methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus spp. in bulk tank milk samples from 288 organic and conventional dairy farms located in New York, Wisconsin, and Oregon from March 2009 to May 2011. Due to recent publications reporting the presence mecC (a mecA homolog not detected by traditional mecA-based PCR methods), a combination of genotypic and phenotypic approaches was used to enhance the recovery of methicillin-resistant organisms from bulk tank milk. In total, 13 isolates were identified as methicillin resistant: Staph. aureus (n=1), Staphylococcus sciuri (n=5), Staphylococcus chromogenes (n=2), Staphylococcus saprophyticus (n=3), Staphylococcus agnetis (n=1), and Macrococcus caseolyticus (n=1). The single methicillin-resistant Staph. aureus isolate was identified from an organic farm in New York, for an observed 0.3% prevalence at the farm level. The methicillin-resistant coagulase-negative staphylococci prevalence was 2% in the organic population and 5% in the conventional population. We did not identify mecC in any of the isolates from our population. Of interest was the relatively high number of methicillin-resistant Staph. sciuri recovered, as the number of isolates from our study was considerably higher than those recovered from other recent studies that also assessed milk samples. Our research suggests that the presence of a potential methicillin-resistant Staphylococcus reservoir in milk, and likely the dairy farm population in the United States, is independent of the organic or conventional production system. PMID:24582450

  1. Methicillin-resistant Staphylococcus aureus infected pseudo-arthrosis of the distal tibia treated with debridement, mesh cage, autologous grafting and locking plate fixation

    Motsitsi, Silas N. S.

    2008-01-01

    Infected non-union of long bones is a challenge to manage. It has a high morbidity and mortality. Treatment is very demanding and has a significant complication rate. Methicillin-resistant infected non-union has a higher morbidity and mortality compared to Methicillin-sensitive Staphylococcus aureus infection. Approximately half of all Staphylococci isolated in infected orthopaedic operations are caused by Methicillin-resistant S. aureus. We present a 42-year-old patient who had Methicillin-r...

  2. Risk factors assessment for nasal colonization of Staphylococcus aureus and its methicillin resistant strains among pre-clinical medical students of Nepal

    Ansari, Shamshul; Gautam, Rajendra; Shrestha, Sony; Ansari, Safiur Rahman; Subedi, Shankar Nanda; Chhetri, Muni Raj

    2016-01-01

    Background Staphylococcus aureus (S. aureus), a normal flora of nasal cavity, can cause minor to life threatening invasive diseases and nosocomial infections. Methicillin resistant strains of S. aureus are causing a great challenge for treatment options. Therefore, the purpose of this study was to assess the nasal carriage rate of S. aureus, its methicillin resistant strains and risk factors in medical students prior to clinical exposure. Methods The bacterial growth of S. aureus from nasal s...

  3. Role of the Stringent Stress Response in the Antibiotic Resistance Phenotype of Methicillin-Resistant Staphylococcus aureus.

    Aedo, Sandra; Tomasz, Alexander

    2016-04-01

    Resistance to beta-lactam antibiotics in methicillin-resistantStaphylococcus aureus(MRSA) requires the presence of an acquired genetic determinant,mecAormecC, which encode penicillin-binding protein PBP2A or PBP2A', respectively. Although all MRSA strains share a mechanism of resistance, the phenotypic expression of beta-lactam resistance shows considerable strain-to-strain variation. The stringent stress response, a stress response that results from nutrient limitation, was shown to play a key role in determining the resistance level of an MRSA strain. In the present study, we validated the impact of the stringent stress response on transcription and translation ofmecAin the MRSA clinical isolate strain N315, which also carries known regulatory genes (mecI/mecR1/mecR2andblaI/blaR1) formecAtranscription. We showed that the impact of the stringent stress response on the resistance level may be restricted to beta-lactam resistance based on a "foreign" determinant such asmecA, as opposed to resistance based on mutations in the nativeS. aureusdeterminantpbpB(encoding PBP2). Our observations demonstrate that high-level resistance mediated by the stringent stress response follows the current model of beta-lactam resistance in which the native PBP2 protein is also essential for expression of the resistance phenotype. We also show that theStaphylococcus sciuri pbpDgene (also calledmecAI), the putative evolutionary precursor ofmecA, confers oxacillin resistance in anS. aureusstrain, generating a heterogeneous phenotype that can be converted to high and homogenous resistance by induction of the stringent stress response in the bacteria. PMID:26833147

  4. MULTI DRUG RESISTANCE IN METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS (MRSA ISOLATES FROM A UNIVER SITY HOSPITAL OF WESTERN INDIA

    Ravi

    2013-03-01

    Full Text Available ABSTRACT: BACKGROUND: Methicillin Resistant Staphylococcus aureus (MRSA has emerged as one of the most important nosocomial pathogen. Its remarkable ability to develop resistance to a variety of antibiotics makes it a major threat to public health. OBJECTIVES: - To detect the prevalence and in vitro antimicrobial susceptibility pattern of the MRSA isolates. MATERIALS & METHODS: - 202 Staphylococcus aureus strains isolated from c linical samples like blood, pus, sputum & body fluids were screened for Methicillin r esistance by standard disk diffusion method and then confirmed with Oxacillin Screening agar. Antibiotic susceptibility of both the MRSA and Methicillin sensitive Staphylococcus aureu s (MSSA for other antibiotics was subsequently carried out by standard disc diffusion method. RESULTS: Methicillin resistance was detected in 114 strains of Staphylococcus aureus giving a prevalence rate of 56.44%. More than 80% of the MRSA isolates were resistant to ant ibiotics such as Penicillins, Cephalosporins, Aminoglycosides, Macrolides and Quinolones. All str ains were uniformly sensitive to Vancomycin & Linezolid. Coexisting resistance to mo st of the antibiotics was significantly higher in the MRSA isolates as compared to the MSSA (Methic illin sensitive Staphylococcus aureus isolates (p < 0.001. INTERPRETATION & CONCLUSIONS: Multi drug resistance among the MRSA isolates poses a major hurdle in treating syste mic infections. Monitoring antibiotic sensitivity pattern, implementing aggressive surveill ance measures & good infection control practices would be helpful in reducing the prevalence of MRSA and its multi drug resistance

  5.  In Vitro Antibacterial Activity of three Indian Spices Against Methicillin-Resistant Staphylococcus aureus

    Nishith Kumar Pal

    2011-09-01

    Full Text Available  Objective: To explore the in vitro antibacterial activity of ethanolic extracts of cinnamon (Cinnamomum zeylanicum; CIN, clove (Syzygium aromaticum, CLV and cumin (Cuminum cyminum, CMN against clinical isolates of methicillin resistant Staphylococcus aureus (MRSA, from Kolkata, India.Methods: The CIN, CLV and CMN were tested for their antibacterial activity against MRSA by in vitro methods. Minimum inhibitory concentration (MIC values of the three extracts were determined, and time-kill studies were performed in order to investigate the bactericidal activity of the extracts (at the MIC level for the isolates. The killing efficacy of the extracts was determined at various concentrations.Results: The zone diameter of inhibition (ZDI obtained due to CIN, CLV and CMN ranged between 22-27 mm, 19-23 mm and 9-15 mm, respectively; while the MICs, for the isolates, were in the range of 64-256, 64-512 and 128-512 µg/ml, respectively. When tested for their MIC levels; the CIN and CLV were found to be bactericidal after 6 hrs of incubation, while CMN showed bactericidal activity after 24 hrs. However, when tested at various concentrations; CIN, CLV and CMN displayed bactericidal activity against S. aureus, after 24 hrs of incubation, at 200, 200 and 300 µg/ml, respectively.Conclusion: The C. zeylanicum and S. aromaticum showed the strongest in vitro antibacterial activity followed by C. cyminum against MRSA, and such findings could be considered a valuable support in the treatment of infection and may contribute to the development of potential antimicrobial agents for inclusion in anti- S. aureus regimens.

  6. Methicillin-Resistant Staphylococcus aureus from Brazilian Dairy Farms and Identification of Novel Sequence Types.

    Oliveira, C J B; Tiao, N; de Sousa, F G C; de Moura, J F P; Santos Filho, L; Gebreyes, W A

    2016-03-01

    The aim of this study was to investigate the phenotypic and genotypic diversity and anti-microbial resistance among staphylococci of dairy herds that originated from Paraiba State, north-eastern Brazil, a region where such studies are rare. Milk samples (n = 552) were collected from 15 dairy farms. Isolates were evaluated for anti-microbial susceptibility by Kirby-Bauer disc diffusion method. Confirmation of methicillin-resistant Staphylococcus aureus (MRSA) was performed using multiplex PCR targeting mecA and nuc genes in addition to phenotypic assay based on PBP-2a latex agglutination. Clonal relatedness of isolates was determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) genotyping. Staphylococci were detected in 269 (49%) of the samples. Among these, 65 (24%) were S. aureus. The remaining 204 isolates were either coagulase-negative staphylococci (n = 188; 70%) or coagulase positive other than S. aureus (n = 16; 6%). Staphylococci were cultured in seven (35%) of the 20 hand swab samples, from which five isolates were S. aureus. The isolates were most commonly resistant against penicillin (43%), ampicillin (38%) and oxacillin (27%). The gene mecA was detected in 21 S. aureus from milk and in one isolate from a milker's hand. None of the isolates were resistant to vancomycin. PFGE findings showed high clonal diversity among the isolates. Based on MLST, we identified a total of 11 different sequence types (STs 1, 5, 6, 83, 97, 126, 1583, 1622, 1623, 1624 and 1625) with four novel STs (ST1622-ST1625). The findings show that MRSA is prevalent in milk from semi-extensive dairy cows in north-eastern Brazil, and further investigation on its extent in various types of milk production systems and the farm-to-table continuum is warranted. PMID:26178302

  7. When are the hands of healthcare workers positive for methicillin-resistant Staphylococcus aureus?

    Creamer, E

    2010-06-01

    Hand hygiene is a key component in reducing infection. There are few reports on the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) on healthcare workers\\' (HCWs\\') hands. The aim of this study was to establish whether HCWs\\' fingertips were contaminated with MRSA in a clinical hospital setting. The study was conducted in an acute tertiary referral hospital on four MRSA wards that were part of a larger research study on MRSA epidemiology and four other wards not included in the study. The fingertips from all categories of 523 HCWs were sampled on 822 occasions by the imprinting of fingertips on MRSA chromogenic agar plates. The type of hand hygiene agent used, if any, and the immediate prior activity of the HCW were recorded. Overall, 38\\/822 (5%) fingertips from 523 HCWs were MRSA-positive; 12\\/194 (6%) after clinical contact, 10\\/138 (10%) after contact with the patient\\'s environment and 15\\/346 (4%) after no specific contact. MRSA was recovered on 2\\/61 (3%) occasions after use of alcohol hand rub, 2\\/35 (6%) after 4% chlorhexidine detergent, 7\\/210 (3%) hand washing with soap and water, and 27\\/493 (5%) when no hand hygiene had been performed. MRSA was recovered from HCWs on seven of the eight wards. MRSA was more frequently present on fingertips on the four non-study wards vs the four MRSA study wards [18\\/250 (7%), 3\\/201 (1%), respectively; P

  8. Comparison of antimicrobial agents as therapy for experimental endocarditis: caused by methicillin-resistant Staphylococcus aureus.

    Sacar, Mustafa; Sacar, Suzan; Cevahir, Nural; Onem, Gokhan; Teke, Zafer; Asan, Ali; Turgut, Huseyin; Adali, Fahri; Kaleli, Ilknur; Susam, Ibrahim; Yaylali, Yalin Tolga; Baltalarli, Ahmet

    2010-01-01

    We used an experimental rat model to compare the therapeutic efficacy of teicoplanin, linezolid, and quinupristin/dalfopristin with that of vancomycin as standard therapy for infective endocarditis.Aortic endocarditis was induced in rats by insertion of a polyethylene catheter into the left ventricle, followed by intravenous inoculation of 106 colony-forming units of methicillin-resistant Staphylococcus aureus 24 hours later. Forty-eight hours after bacterial challenge, intravenous antibiotic therapies were initiated. There were 6 groups of 8 rats each: uninfected control; infected, untreated control; vancomycin-treated (40 mg/kg twice daily); teicoplanin-treated (20 mg/kg twice daily after a loading dose of 40 mg/kg); linezolid-treated (75 mg/kg 3 times daily for 1 day, then 75 mg/kg twice daily); and quinupristin/dalfopristin-treated (30 mg/kg twice daily and an additional 10 mg/kg dalfopristin infusion over 6 to 12 hr daily). At the end of therapy, the aortic valve vegetations in the drug-treated rats were evaluated microbiologically.Compared with the infected, untreated group, all drug-treated groups had significantly reduced bacterial titers in the vegetations. Vancomycin, teicoplanin, and quinupristin/dalfopristin all effectively reduced the quantitative bacterial cultures of aortic valve vegetations. In addition, there was no significant difference in the comparative efficacy of teicoplanin, linezolid, and quinupristin/dalfopristin. Vancomycin significantly reduced bacterial counts in comparison with linezolid, which was nonetheless also effective.Our experimental model showed that each of the investigated antimicrobial agents was effective in the treatment of infective endocarditis. PMID:20844611

  9. Antimicrobial resistance and molecular analysis of methicillin-resistant Staphylococcus aureus collected in a Spanish hospital.

    Hernández-Porto, Miriam; Lecuona, María; Aguirre-Jaime, Armando; Castro, Beatriz; Delgado, Teresa; Cuervo, Milagros; Pedroso, Yanet; Arias, Ángeles

    2015-04-01

    Clonal distribution of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals may differ according to the geographic location and time period. Knowledge of MRSA clonal epidemiology in hospital settings involves much more than the study of healthcare-associated MRSA (HA-MRSA) clones. In recent years, investigators have documented the introduction of both community-associated MRSA (CA-MRSA) and livestock-associated MRSA (LA-MRSA) clones, the emergence of clones carrying Staphylococcal cassette chromosome mec (SCCmec) XI, and the genetic diversity among sporadic MRSA isolates. The allocation of certain antibiotypes to dominant MRSA clones in an institution allows their use as phenotypic markers for a preliminary search for new clones, early detection of clonal shift, and as a guide for better empirical therapy, infection control, and treatment within a particular institution. For these reasons, we identified 938 strains detected in a System of Universal Active Surveillance of MRSA in clinical samples during the period 2009-2010, obtaining the clonal distribution of MRSA at the Hospital Universitario de Canarias (Tenerife, Spain) and the relationship between antimicrobial susceptibility and three major clones present. The antibiotypes that best defined the ST5-MRSA-IV (Pediatric) clone showed resistance to tobramycin and susceptibility to clindamycin, erythromycin, gentamicin, rifampin, trimethoprim-sulfamethoxazole, vancomycin, quinupristin/dalfopristin, and linezolid, whereas the ST22-MRSA-IV clone (EMRSA-15) showed susceptibility to these antibiotics, and finally, the ST36-MRSA-II clone (EMRSA-16) was resistant to clindamycin, erythromycin, and tobramycin and susceptible to the remaining antimicrobials. Similar observations would allow the early detection of changes in clonal epidemiology by analysis of antimicrobial susceptibility of the isolates within a single institution. PMID:25365597

  10. Effects of Subinhibitory Concentrations of Ceftaroline on Methicillin-Resistant Staphylococcus aureus (MRSA Biofilms.

    María Lázaro-Díez

    Full Text Available Ceftaroline (CPT is a novel cephalosporin with in vitro activity against Staphylococcus aureus. Ceftaroline exhibits a level of binding affinity for PBPs in S. aureus including PBP2a of methicillin-resistant S. aureus (MRSA. The aims of this study were to investigate the morphological, physiological and molecular responses of MRSA clinical strains and MRSA biofilms to sub-MICs (1/4 and 1/16 MIC of ceftaroline by using transmission, scanning and confocal microscopy. We have also used quantitative Real-Time PCR to study the effect of sub-MICs of ceftaroline on the expression of the staphylococcal icaA, agrA, sarA and sasF genes in MRSA biofilms. In one set of experiments, ceftaroline was able to inhibit biofilm formation in all strains tested at MIC, however, a strain dependent behavior in presence of sub-MICs of ceftaroline was shown. In a second set of experiments, destruction of preformed biofilms by addition of ceftaroline was evaluated. Ceftaroline was able to inhibit biofilm formation at MIC in all strains tested but not at the sub-MICs. Destruction of preformed biofilms was strain dependent because the biofilm formed by a matrix-producing strain was resistant to a challenge with ceftaroline at MIC, whereas in other strains the biofilm was sensitive. At sub-MICs, the impact of ceftaroline on expression of virulence genes was strain-dependent at 1/4 MIC and no correlation between ceftaroline-enhanced biofilm formation and gene regulation was established at 1/16 MIC. Our findings suggest that sub-MICs of ceftaroline enhance bacterial attachment and biofilm formation by some, but not all, MRSA strains and, therefore, stress the importance of maintaining effective bactericidal concentrations of ceftaroline to fight biofilm-MRSA related infections.

  11. Occurrence of methicillin-resistant Staphylococcus aureus in surface waters near industrial hog operation spray fields.

    Hatcher, S M; Myers, K W; Heaney, C D; Larsen, J; Hall, D; Miller, M B; Stewart, J R

    2016-09-15

    Industrial hog operations (IHOs) have been identified as a source of antibiotic-resistant Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). However, few studies have investigated the presence of antibiotic-resistant S. aureus in the environment near IHOs, specifically surface waters proximal to spray fields where IHO liquid lagoon waste is sprayed. Surface water samples (n=179) were collected over the course of approximately one year from nine locations in southeastern North Carolina and analyzed for the presence of presumptive MRSA using CHROMagar MRSA media. Culture-based, biochemical, and molecular tests, as well as matrix-assisted laser desorption/ionization-time of flight mass spectrometry were used to confirm that isolates that grew on CHROMagar MRSA media were S. aureus. Confirmed S. aureus isolates were then tested for susceptibility to 16 antibiotics and screened for molecular markers of MRSA (mecA, mecC) and livestock adaptation (absence of scn). A total of 12 confirmed MRSA were detected in 9 distinct water samples. Nine of 12 MRSA isolates were also multidrug-resistant (MDRSA [i.e., resistant to ≥3 antibiotic classes]). All MRSA were scn-positive and most (11/12) belonged to a staphylococcal protein A (spa) type t008, which is commonly associated with humans. Additionally, 12 confirmed S. aureus that were methicillin-susceptible (MSSA) were recovered, 7 of which belonged to spa type t021 and were scn-negative (a marker of livestock-adaptation). This study demonstrated the presence of MSSA, MRSA, and MDRSA in surface waters adjacent to IHO lagoon waste spray fields in southeastern North Carolina. To our knowledge, this is the first report of waterborne S. aureus from surface waters proximal to IHOs. PMID:27261430

  12. Methicillin-resistant Staphylococcus aureus in Ohio EMS Providers: A Statewide Cross-sectional Study.

    Orellana, Robert C; Hoet, Armando E; Bell, Christopher; Kelley, Christina; Lu, Bo; Anderson, Sarah E; Stevenson, Kurt B

    2016-01-01

    The objective was to determine the nasal carriage prevalence of methicillin-resistant Staphylococcus aureus (MRSA) among emergency medical service (EMS) personnel and the associated risk factors. A cross-sectional study was conducted among Ohio EMS personnel randomly sampled from 84 urban and rural agencies. Surveys assessing demographics, occupational history, health, cohabitation status, and hygiene practice were collected with nasal swabs from those who enrolled. Survey weight adjusted analysis was performed (1) to estimate MRSA nasal carriage prevalence of Ohio EMS providers, and (2) to identify variables associated with MRSA. MRSA was detected in 4.6% (13/280) EMS personnel sampled. After employing a survey-weighted analysis the following risk factors associated with MRSA carriage were identified: those who did not practice frequent hand hygiene after glove use (OR, 10.51; 95% CI, 2.54-43.45; P = 0.0012), living with someone with a recent staphylococcal infection (OR, 9.02; 95% CI, 1.03-78.98; P = 0.0470), and individuals with low frequency of hand washing (< 8 times per shift) (OR, 4.20; 95% CI 1.02-17.27; P = 0.0468). An additional risk factor identified through the logistic regression analysis on the study population was EMS workers with an open wound or skin infection (OR, 6.75; 95% CI, 1.25-36.36; P = 0.0262). However, this was not significant in the survey-weighted analysis. The high prevalence of MRSA in Ohio EMS personnel is both an occupational hazard and patient safety concern. Implementing methods to reinforce CDC guidelines for proper hygiene could decrease MRSA found in the EMS setting. Previous literature suggests that a reduction in MRSA colonization can lead to decreases in transmission and improved health for both patients and personnel. PMID:26516797

  13. Antibacterial Activity and Antibiotic-Enhancing Effects of Honeybee Venom against Methicillin-Resistant Staphylococcus aureus.

    Han, Sang Mi; Kim, Joung Min; Hong, In Pyo; Woo, Soon Ok; Kim, Se Gun; Jang, He Rye; Pak, Sok Cheon

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA), along with other antibiotic resistant bacteria, has become a significant social and clinical problem. There is thus an urgent need to develop naturally bioactive compounds as alternatives to the few antibiotics that remain effective. Here we assessed the in vitro activities of bee venom (BV), alone or in combination with ampicillin, penicillin, gentamicin or vancomycin, on growth of MRSA strains. The antimicrobial activity of BV against MRSA strains was investigated using minimum inhibitory concentrations (MIC), minimum bactericidal concentrations (MBC) and a time-kill assay. Expression of atl which encodes murein hydrolase, a peptidoglycan-degrading enzyme involved in cell separation, was measured by reverse transcription-polymerase chain reaction. The MICs of BV were 0.085 µg/mL and 0.11 µg/mL against MRSA CCARM 3366 and MRSA CCARM 3708, respectively. The MBC of BV against MRSA 3366 was 0.106 µg/mL and that against MRSA 3708 was 0.14 µg/mL. The bactericidal activity of BV corresponded to a decrease of at least 3 log CFU/g cells. The combination of BV with ampicillin or penicillin yielded an inhibitory concentration index ranging from 0.631 to 1.002, indicating a partial and indifferent synergistic effect. Compared to ampicillin or penicillin, both MRSA strains were more susceptible to the combination of BV with gentamicin or vancomycin. The expression of atl gene was increased in MRSA 3366 treated with BV. These results suggest that BV exhibited antibacterial activity and antibiotic-enhancing effects against MRSA strains. The atl gene was increased in MRSA exposed to BV, suggesting that cell division was interrupted. BV warrants further investigation as a natural antimicrobial agent and synergist of antibiotic activity. PMID:26771592

  14. Characterization of Fosfomycin Resistance Gene, fosB, in Methicillin-Resistant Staphylococcus aureus Isolates

    Chen, Chunhui; Guo, Yan; Ma, Ying; Yang, Yang; Hu, Fupin; Xu, Xiaogang; Wang, Minggui

    2016-01-01

    To investigate the prevalence, location and genetic environments of fosfomycin-resistance (fos) genes in methicillin-resistant Staphylococcus aureus (MRSA) clinical strains, 67 fosfomycin-resistant MRSA strains were isolated from the blood and cerebrospinal fluid samples at a teaching hospital in Shanghai. The presence of fos genes in these clinical strains was detected by PCR and sequencing. The locations of fos genes were determined by Southern blotting and genetic environments were analyzed by primer walking sequencing. Multiple locus sequence typing (MLST) was used to characterize genetic diversity. Conjugation was performed to evaluate the transferability of fos genes. Among 67 fosfomycin-resistant MRSA strains, nine high level fosfomycin resistant strains (≥128 μg/ml) were fosB-positive. Three new subtypes of fosB, designated as fosB4, fosB5, and fosB6, were identified. fosB1, fosB4 or fosB6 genes were located on small plasmids (ca. 2.5 kb) and flanked by an analogous replication gene (rep). Differently, the fosB5 gene was surrounded by a shorter rep gene and two copies of a transposon gene (tnp) that shared high identity with the IS257-like transposon. Four MLST types were found among the nine fosB-positive strains. Transconjugants with the fosB genes were resistant to fosfomycin with MIC 64 or 128 μg/ml. In conclusion, different subtypes and genetic environment of fosB genes indicate that gene heterogeneity for fosfomycin resistance in MRSA isolates. PMID:27144405

  15. Characterization of Fosfomycin Resistance Gene, fosB, in Methicillin-Resistant Staphylococcus aureus Isolates.

    Zhuyingjie Fu

    Full Text Available To investigate the prevalence, location and genetic environments of fosfomycin-resistance (fos genes in methicillin-resistant Staphylococcus aureus (MRSA clinical strains, 67 fosfomycin-resistant MRSA strains were isolated from the blood and cerebrospinal fluid samples at a teaching hospital in Shanghai. The presence of fos genes in these clinical strains was detected by PCR and sequencing. The locations of fos genes were determined by Southern blotting and genetic environments were analyzed by primer walking sequencing. Multiple locus sequence typing (MLST was used to characterize genetic diversity. Conjugation was performed to evaluate the transferability of fos genes. Among 67 fosfomycin-resistant MRSA strains, nine high level fosfomycin resistant strains (≥128 μg/ml were fosB-positive. Three new subtypes of fosB, designated as fosB4, fosB5, and fosB6, were identified. fosB1, fosB4 or fosB6 genes were located on small plasmids (ca. 2.5 kb and flanked by an analogous replication gene (rep. Differently, the fosB5 gene was surrounded by a shorter rep gene and two copies of a transposon gene (tnp that shared high identity with the IS257-like transposon. Four MLST types were found among the nine fosB-positive strains. Transconjugants with the fosB genes were resistant to fosfomycin with MIC 64 or 128 μg/ml. In conclusion, different subtypes and genetic environment of fosB genes indicate that gene heterogeneity for fosfomycin resistance in MRSA isolates.

  16. Contribution of Panton-Valentine leukocidin in community-associated methicillin-resistant Staphylococcus aureus pathogenesis.

    Binh An Diep

    Full Text Available Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA strains typically carry genes encoding Panton-Valentine leukocidin (PVL. We used wild-type parental and isogenic PVL-deletion (Delta pvl strains of USA300 (LAC and SF8300 and USA400 (MW2 to test whether PVL alters global gene regulatory networks and contributes to pathogenesis of bacteremia, a hallmark feature of invasive staphylococcal disease. Microarray and proteomic analyses revealed that PVL does not alter gene or protein expression, thereby demonstrating that any contribution of PVL to CA-MRSA pathogenesis is not mediated through interference of global gene regulatory networks. Inasmuch as a direct role for PVL in CA-MRSA pathogenesis remains to be determined, we developed a rabbit bacteremia model of CA-MRSA infection to evaluate the effects of PVL. Following experimental infection of rabbits, an animal species whose granulocytes are more sensitive to the effects of PVL compared with the mouse, we found a contribution of PVL to pathogenesis over the time course of bacteremia. At 24 and 48 hours post infection, PVL appears to play a modest, but measurable role in pathogenesis during the early stages of bacteremic seeding of the kidney, the target organ from which bacteria were not cleared. However, the early survival advantage of this USA300 strain conferred by PVL was lost by 72 hours post infection. These data are consistent with the clinical presentation of rapid-onset, fulminant infection that has been associated with PVL-positive CA-MRSA strains. Taken together, our data indicate a modest and transient positive effect of PVL in the acute phase of bacteremia, thereby providing evidence that PVL contributes to CA-MRSA pathogenesis.

  17. Methicillin-resistant Staphylococcus aureus associated with animals and its relevance to human health

    AnnalisaPantosti

    2012-04-01

    Full Text Available Staphylococcus aureus is a typical human pathogen. Some animal S. aureus lineages have derived from human strains following profound genetic adaptation determining a change in host specificity. Due to the close relationship of animals with the environmental microbioma and resistoma, animal staphylococcal strains also represent a source of resistance determinants. Methicillin-resistant S. aureus (MRSA emerged fifty years ago as a nosocomial pathogen but in the last decade it has also become a frequent cause of infections in the community. The recent finding that MRSA frequently colonizes animals, especially livestock, has been a reason for concern, as it has revealed an expanded reservoir of MRSA. While MRSA strains recovered from companion animals are generally similar to human nosocomial MRSA, MRSA strains recovered from food animals appear to be specific animal-adapted clones. Since 2005, MRSA belonging to ST398 was recognized as a colonizer of pigs and human subjects professionally exposed to pig farming. The “pig” MRSA was also found to colonize other species of farmed animals, including horses, cattle and poultry and was therefore designated livestock-associated (LA-MRSA. LA-MRSA ST398 can cause infections in humans in contact with animals, and can infect hospitalized people, although at the moment this occurrence is relatively rare. Other animal-adapted MRSA clones have been detected in livestock, such as ST1 and ST9. Recently, ST130 MRSA isolated from bovine mastitis has been found to carry a novel mecA gene that eludes detection by conventional PCR tests. Similar ST130 strains have been isolated from human infections in UK, Denmark and Germany at low frequency. It is plausible that the increased attention to animal MRSA will reveal other strains with peculiar characteristics that can pose a risk to human health.

  18. Antibacterial Activity and Antibiotic-Enhancing Effects of Honeybee Venom against Methicillin-Resistant Staphylococcus aureus

    Sang Mi Han

    2016-01-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA, along with other antibiotic resistant bacteria, has become a significant social and clinical problem. There is thus an urgent need to develop naturally bioactive compounds as alternatives to the few antibiotics that remain effective. Here we assessed the in vitro activities of bee venom (BV, alone or in combination with ampicillin, penicillin, gentamicin or vancomycin, on growth of MRSA strains. The antimicrobial activity of BV against MRSA strains was investigated using minimum inhibitory concentrations (MIC, minimum bactericidal concentrations (MBC and a time-kill assay. Expression of atl which encodes murein hydrolase, a peptidoglycan-degrading enzyme involved in cell separation, was measured by reverse transcription-polymerase chain reaction. The MICs of BV were 0.085 µg/mL and 0.11 µg/mL against MRSA CCARM 3366 and MRSA CCARM 3708, respectively. The MBC of BV against MRSA 3366 was 0.106 µg/mL and that against MRSA 3708 was 0.14 µg/mL. The bactericidal activity of BV corresponded to a decrease of at least 3 log CFU/g cells. The combination of BV with ampicillin or penicillin yielded an inhibitory concentration index ranging from 0.631 to 1.002, indicating a partial and indifferent synergistic effect. Compared to ampicillin or penicillin, both MRSA strains were more susceptible to the combination of BV with gentamicin or vancomycin. The expression of atl gene was increased in MRSA 3366 treated with BV. These results suggest that BV exhibited antibacterial activity and antibiotic-enhancing effects against MRSA strains. The atl gene was increased in MRSA exposed to BV, suggesting that cell division was interrupted. BV warrants further investigation as a natural antimicrobial agent and synergist of antibiotic activity.

  19. Differentiation of clonal complex 59 community-associated methicillin-resistant Staphylococcus aureus in Western Australia.

    Coombs, Geoffrey W; Monecke, Stefan; Ehricht, Ralf; Slickers, Peter; Pearson, Julie C; Tan, Hui-Leen; Christiansen, Keryn J; O'Brien, Frances G

    2010-05-01

    Clonal complex 59 (CC59) community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains were characterized using pulsed-field gel electrophoresis, spa typing, multilocus sequence typing, diagnostic DNA microarrays, and PCRs targeting staphylococcal cassette chromosome mec (SCCmec) elements and Panton-Valentine leukocidin (PVL). Six distinct groups within CC59 were characterized. At least seven different variants of SCCmec elements were identified (IVa [2B], IVb [2B], IVd [2B], IV variant [2B], IVa [2B&5], V variant [5C2], and V [5C2&5]). (The structural type is indicated by a Roman numeral, with a lowercase letter indicating the subtype, and the ccr complex and the mec complex are indicated by an Arabic numeral and an uppercase letter, respectively. Where there is an extra ccr element, this is indicated by "&" and an Arabic numeral designating the ccr type.) The first group is similar to the American sequence type 59 (ST59) MRSA-IV CA-MRSA strain USA1000. The second group includes a PVL-negative ST87 strain with an SCCmec element of subtype IVb (2B). The third group comprises PVL-variable ST59 MRSA-IV strains harboring multiple SCCmec IV subtypes. PVL-negative ST59 MRSA strains with multiple or composite SCCmec elements (IVa [2B&5]) form the fourth group. Group 5 corresponds to the internationally known "Taiwan clone," a PVL-positive strain with a variant SCCmec element (V [5C2&5]). This strain proved to be the most common CC59 MRSA strain isolated in Western Australia. Finally, group 6 encompasses the ST59 MRSA-V variant (5C2). The differentiation of CC59 into groups and strains indicates a rapid evolution and spread of SCCmec elements. Observed differences between groups of strains as well as intrastrain variability within a group facilitate the tracing of their spread. PMID:20211891

  20. Nasal carriage of methicillin-resistant Staphylococcus aureus among pediatricians in Taiwan.

    Yhu-Chering Huang

    Full Text Available BACKGROUND: Health care workers (HCWs are at the interface between hospitals and communities. The survey for methicillin-resistant Staphylococcus aureus (MRSA carriage among HCWs has mostly been conducted to investigate outbreaks or endemics. Community-associated MRSA are prevalent among children in Taiwan. We conducted this study to better understand the carriage rate of MRSA among pediatricians in non-outbreak situations in Taiwan,. METHODS: A total of 220 pediatricians from Taiwan who attended the annual meeting of Taiwan Pediatric Association in April, 2010 were recruited to participate in this study and were sampled from the nares for the detection of MRSA by polymerase chain reaction (PCR and further by culture. The following molecular analyses were performed, including pulsed-field gel electrophoresis (PFGE, multilocus sequence typing (MLST, typing of staphylococcal cassette chromosome mec (SCCmec and the presence of Panton-Valentine leukocidin (PVL genes. RESULTS: MRSA was detected from 15 attendees (6.8% by PCR. MRSA-colonized attendees had a significantly lower rate (0.041 of working in the medical center, while borderline significantly higher rate of working in the Regional Hospital (p=0.056, than those without MRSA colonization. From those 15 samples, 12 MRSA isolates were identified by culture and molecularly characterized. Three PFGE patterns, two sequence types (ST 59, ST 508, and two SCCmec types (IV and VT were identified, respectively. Five isolates, including three carrying SCCmec types VT, were PVL-positive. All 12 isolates were susceptible to vancomycin, teicoplanin, linezolid, fusidic acid, trimethoprim/sulfamethoxazole, and doxycyclin, and resistant to penicillin. CONCLUSION/SIGNIFICANCE: Around seven percent of pediatricians in Taiwan harbored CA-MRSA in their nares.

  1. Sampling, prevalence and characterization of methicillin-resistant Staphylococcus aureus on two Belgian pig farms

    Isabelle Dewaele

    2011-02-01

    Full Text Available This study investigated the spread of MRSA (methicillin-resistant Staphylococcus aureus on two Belgian pig farms. Pigs of different ages (from farrowing to slaughter age and sows as well as the barn environment were screened extensively on two occasions three months apart. A subset of MRSA isolates was tested for antimicrobial susceptibility to 16 antibiotics and was further characterized by pulsed-field gel electrophoresis. Ninety-five percent and 77% of the tested pigs on farm A and farm B, respectively, were colonized with MRSA. MRSA positive animals were detected in all age categories sampled on each sampling day. Piglets were already colonized in the farrowing unit with the same or other MRSA strains than their mother. The prevalence of MRSA colonized pigs increased significantly after weaning and decreased during the fattening period. Pigs carried MRSA mainly in the nares, followed by the perineum and skin and to a lesser degree the rectum. A pig could be contaminated or colonized with different MRSA strains at the same time. The barn environment was also found to be contaminated with different MRSA strains, including the air inlet and outlet. All isolates tested on both farms were resistant to both tetracycline and trimethoprim, while they were susceptible to rifampicin, mupirocin and linezolid. There was a significant difference in resistance prevalence between the two farms for the antibiotics gentamicin, kanamycin, tobramycin, tylosin, lincomycin and quinupristin/dalfopristin. Furthermore, several antibiotic resistance profiles were observed within one farm. This study clearly indicates that several MRSA strains circulate on one farm, from the nursery unit to the fattening unit. This is important to consider when attempts are made to remediate these farms.

  2. Molecular detection and characterization of methicillin-resistant Staphylococcus aureus (MRSA) isolates from dogs in Portugal.

    Coelho, Céline; Torres, Carmen; Radhouani, Hajer; Pinto, Luís; Lozano, Carmen; Gómez-Sanz, Elena; Zaragaza, Myriam; Igrejas, Gilberto; Poeta, Patrícia

    2011-06-01

    Fifty-four healthy dogs were screened in Portugal for the presence of nasal methicillin-resistant Staphylococcus aureus (MRSA) carriage. Sixteen MRSA isolates (one/sample) were recovered from nasal samples of dogs, and they were typed by molecular methods (S. aureus protein A [spa]-, multilocus sequence typing-, staphylococcal cassette chromosome mec-typing). MRSA isolates were investigated for their susceptibility to antimicrobial agents by disk-diffusion test. The presence of resistance genes and of the Panton-Valentine leukocidin gene (lukF-lukS) was analyzed by PCR. Four different spa-types were identified among our MRSA isolates (t032, t432, t747, and t4726), with t032 as the most frequently detected. The sequence-type ST22 was identified in four tested MRSA isolates with different spa-types. All 16 isolates presented the staphylococcal cassette chromosome mec type IV. Most of MRSA isolates were resistant to ciprofloxacin, erythromycin, and clindamycin (94%-100%), and no resistance was identified to chloramphenicol, mupirocin, and trimethoprim-sulfametoxazole. The ermC and tetM resistance genes were detected in all MRSA isolates. The amino acid changes Ser84Leu in GyrA protein and Ser80Phe in GrlA protein were the most prevalent ones in our MRSA isolates. None of the MRSA strains carried the lukF-lukS genes. The results presented in this study indicate that healthy dogs may be a reservoir of MRSA that could be transmitted to humans by direct contact. PMID:21254810

  3. Antimicrobial activity of zinc and titanium dioxide nanoparticles against biofilm-producing methicillin-resistant Staphylococcus aureus

    Jesline, A.; John, Neetu P.; Narayanan, P. M.; Vani, C.; Murugan, Sevanan

    2015-02-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major nosocomial pathogens responsible for a wide spectrum of infections and the emergence of bacterial resistance to antibiotics has lead to treatment drawbacks towards large number of drugs. Formation of biofilms is the main contributing factor to antibiotic resistance. The development of reliable processes for the synthesis of zinc oxide nanoparticles is an important aspect of nanotechnology today. Zinc oxide and titanium dioxide nanoparticles comprise well-known inhibitory and bactericidal effects. Emergence of antimicrobial resistance by pathogenic bacteria is a major health problem in recent years. This study was designed to determine the efficacy of zinc and titanium dioxide nanoparticles against biofilm producing methicillin-resistant S. aureus. Biofilm production was detected by tissue culture plate method. Out of 30 MRSA isolates, 22 isolates showed strong biofilm production and 2 showed weak and moderate biofilm formation. Two strong and weak biofilm-producing methicillin-resistant S. aureus isolates were subjected to antimicrobial activity using commercially available zinc and titanium dioxide nanoparticles. Thus, the nanoparticles showed considerably good activity against the isolates, and it can be concluded that they may act as promising, antibacterial agents in the coming years.

  4. Transmission Clusters of Methicillin-Resistant Staphylococcus Aureus in Long-Term Care Facilities Based on Whole-Genome Sequencing.

    Stine, O Colin; Burrowes, Shana; David, Sophia; Johnson, J Kristie; Roghmann, Mary-Claire

    2016-06-01

    OBJECTIVE To define how often methicillin-resistant Staphylococcus aureus (MRSA) is spread from resident to resident in long-term care facilities using whole-genome sequencing DESIGN Prospective cohort study SETTING A long-term care facility PARTICIPANTS Elderly residents in a long-term care facility METHODS Cultures for MRSA were obtained weekly from multiple body sites from residents with known MRSA colonization over 12-week study periods. Simultaneously, cultures to detect MRSA acquisition were obtained weekly from 2 body sites in residents without known MRSA colonization. During the first 12-week cycle on a single unit, we sequenced 8 MRSA isolates per swab for 2 body sites from each of 6 residents. During the second 12-week cycle, we sequenced 30 MRSA isolates from 13 residents with known MRSA colonization and 3 residents who had acquired MRSA colonization. RESULTS MRSA isolates from the same swab showed little genetic variation between isolates with the exception of isolates from wounds. The genetic variation of isolates between body sites on an individual was greater than that within a single body site with the exception of 1 sample, which had 2 unrelated strains among the 8 isolates. In the second cycle, 10 of 16 residents colonized with MRSA (63%) shared 1 of 3 closely related strains. Of the 3 residents with newly acquired MRSA, 2 residents harbored isolates that were members of these clusters. CONCLUSIONS Point prevalence surveys with whole-genome sequencing of MRSA isolates may detect resident-to-resident transmission more accurately than routine surveillance cultures for MRSA in long-term care facilities. Infect Control Hosp Epidemiol 2016;37:685-691. PMID:26941060

  5. Successful treatment of methicillin-resistant Staphylococcus aureus osteomyelitis with combination therapy using linezolid and rifampicin under therapeutic drug monitoring.

    Ashizawa, Nobuyuki; Tsuji, Yasuhiro; Kawago, Koyomi; Higashi, Yoshitsugu; Tashiro, Masato; Nogami, Makiko; Gejo, Ryuichi; Narukawa, Munetoshi; Kimura, Tomoatsu; Yamamoto, Yoshihiro

    2016-05-01

    Linezolid is an effective antibiotic against most gram-positive bacteria including drug-resistant strains such as methicillin-resistant Staphylococcus aureus. Although linezolid therapy is known to result in thrombocytopenia, dosage adjustment or therapeutic drug monitoring of linezolid is not generally necessary. In this report, however, we describe the case of a 79-year-old woman with recurrent methicillin-resistant S. aureus osteomyelitis that was successfully treated via surgery and combination therapy using linezolid and rifampicin under therapeutic drug monitoring for maintaining an appropriate serum linezolid concentration. The patient underwent surgery for the removal of the artificial left knee joint and placement of vancomycin-impregnated bone cement beads against methicillin-resistant S. aureus after total left knee implant arthroplasty for osteoarthritis. We also initiated linezolid administration at a conventional dose of 600 mg/h at 12-h intervals, but reduced it to 300 mg/h at 12-h intervals on day 9 because of a decrease in platelet count and an increase in serum linezolid trough concentration. However, when the infection exacerbated, we again increased the linezolid dose to 600 mg/h at 12-h intervals and performed combination therapy with rifampicin, considering their synergistic effects and the control of serum linezolid trough concentration via drug interaction. Methicillin-resistant S. aureus infection improved without reducing the dose of or discontinuing linezolid. The findings in the present case suggest that therapeutic drug monitoring could be useful for ensuring the therapeutic efficacy and safety of combination therapy even in patients with osteomyelitis who require long-term antibiotic administration. PMID:26732509

  6. Surgimiento y diseminación de Staphylococcus aureus meticilinorresistente Staphylococcus aureus methicillin-resistant: emergence and dissemination

    Maria Elena Velázquez-Meza

    2005-10-01

    Full Text Available Las infecciones nosocomiales ocasionadas por cepas de Staphylococcus aureus meticilinorresistentes (SAMR son un problema de salud importante en todo el mundo. Este microorganismo produce una gran variedad de infecciones incluyendo osteomielitis, endocarditis invasora, artritis séptica y septicemia. La multirresistencia es un factor que influye en la persistencia de los SAMR dentro del ámbito hospitalario. La introducción de técnicas de tipificación molecular dentro de las investigaciones epidemiológicas ha provisto nuevas herramientas para conocer el origen y las vías de diseminación de este microorganismo. Una de las conclusiones importantes que han surgido de este tipo de estudios es que un número pequeño de clonas son las responsables de las infecciones estafilocócicas en todo el mundo.Nosocomial infections due to methicillin-resistant Staphylococcus aureus (MRSA is an important health problem worldwide. This microorganism causes a variety of clinical infections, including osteomyelitis, invasive endocarditis, septic arthritis and septicemia. Antimicrobial resistance is a factor that influences the persistence of MRSA in the hospital environment. The introduction of molecular typing techniques in epidemiological investigations has provided new tools for identifying the microorganism's origin and routes of dissemination. One of the most important conclusions that have resulted from these types of studies is that a small number of clones are responsible for most of the staphylococcal infections throughout the world.

  7. Characterization of staphylococci in urban wastewater treatment plants in Spain, with detection of methicillin resistant Staphylococcus aureus ST398.

    Gómez, Paula; Lozano, Carmen; Benito, Daniel; Estepa, Vanesa; Tenorio, Carmen; Zarazaga, Myriam; Torres, Carmen

    2016-05-01

    The objective of this study was to determine the prevalence of Staphylococcus in urban wastewater treatment plants (UWTP) of La Rioja (Spain), and to characterize de obtained isolates. 16 wastewater samples (8 influent, 8 effluent) of six UWTPs were seeded on mannitol-salt-agar and oxacillin-resistance-screening-agar-base for staphylococci and methicillin-resistant Staphylococcus aureus recovery. Antimicrobial susceptibility profile was determined for 16 antibiotics and the presence of 35 antimicrobial resistance genes and 14 virulence genes by PCR. S. aureus was typed by spa, agr, and multilocus-sequence-typing, and the presence of immune-evasion-genes cluster was analyzed. Staphylococcus spp. were detected in 13 of 16 tested wastewater samples (81%), although the number of CFU/mL decreased after treatment. 40 staphylococci were recovered (1-5/sample), and 8 of them were identified as S. aureus being typed as (number of strains): spa-t011/agr-II/ST398 (1), spa-t002/agr-II/ST5 (2), spa-t3262/agr-II/ST5 (1), spa-t605/agr-II/ST126 (3), and spa-t878/agr-III/ST2849 (1). S. aureus ST398 strain was methicillin-resistant and showed a multidrug resistance phenotype. Virulence genes tst, etd, sea, sec, seg, sei, sem, sen, seo, and seu, were detected among S. aureus and only ST5 strains showed genes of immune evasion cluster. Thirty-two coagulase-negative Staphylococcus of 12 different species were recovered (number of strains): Staphylococcus equorum (7), Staphylococcus vitulinus (4), Staphylococcus lentus (4), Staphylococcus sciuri (4), Staphylococcus fleurettii (2), Staphylococcus haemolyticus (2), Staphylococcus hominis (2), Staphylococcus saprophyticus (2), Staphylococcus succinus (2), Staphylococcus capitis (1), Staphylococcus cohnii (1), and Staphylococcus epidermidis (1). Five presented a multidrug resistance phenotype. The following resistance and virulence genes were found: mecA, lnu(A), vga(A), tet(K), erm(C), msr(A)/(B), mph(C), tst, and sem. We found that

  8. Prevalence and antimicrobial susceptibility pattern of methicillin resistant Staphylococcus aureus isolates from Trinidad & Tobago

    Monteil Michele

    2006-07-01

    Full Text Available Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA has become increasingly prevalent worldwide since it was first reported in a British hospital. The prevalence however, varies markedly in hospitals in the same country, and from one country to another. We therefore sought to document comprehensively the prevalence and antimicrobial susceptibility pattern of MRSA isolates in Trinidad and Tobago. Methods All Staphylococcus aureus isolates encountered in routine clinical specimens received at major hospitals in the country between 2000 and 2001 were identified morphologically and biochemically by standard laboratory procedures including latex agglutination test (Staphaurex Plus; Murex Diagnostics Ltd; Dartford, England; tube coagulase test with rabbit plasma (Becton, Dickinson & Co; Sparks, MD, USA, and DNase test using DNase agar (Oxoid Ltd; Basingstoke, Hampshire, England. MRSA screening was performed using Mueller-Hinton agar containing 6 μg oxacillin and 4% NaCl, latex agglutination test (Denka Seiken Co. Ltd, Tokyo, Japan and E-test system (AB Biodisk, Solna, Sweden. Susceptibility to antimicrobial agents was determined by the modified Kirby Bauer disc diffusion method while methicillin MICs were determined with E-test system. Results Of 1,912 S. aureus isolates received, 12.8% were methicillin (oxacillin resistant. Majority of the isolates were recovered from wound swabs (86.9% and the least in urine (0.4% specimens. Highest number of isolates was encountered in the surgical (62.3% and the least from obstetrics and gynaecology (1.6% facilities respectively. Large proportions of methicillin sensitive isolates are >85% sensitive to commonly used and available antimicrobials in the country. All MRSA isolates were resistant to ceftriaxone, erythromycin, gentamicin and penicillin but were 100% sensitive to vancomycin, rifampin and chloramphenicol. Conclusion There is a progressive increase in MRSA prevalence in the country but

  9. Disorganization of cell division of methicillin-resistant Staphylococcus aureus by methanolic extract from Phyllanthus columnaris stem bark

    Adnalizawati, A. Siti Noor; Nazlina, I. [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Yaacob, W. A. [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2013-11-27

    The in vitro activity of methanolic extract from Phyllanthus columnaris stem bark was studied against Methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300 and MRSA BM1 (clinical strain) using time-kill curves in conjunction with scanning and transmission electron microscopy. The extract showed more markedly bactericidal activity in MRSA BM1 clinical strain within less than 4 h by 6.25-12.5 mg/mL and within 6 h by 1.56 mg/mL. Scanning electron microscopy of MRSA BM1 revealed distortion of cell whilst transmission electron microscopy revealed disruption in cell wall division.

  10. Cost-Effective Frozen Master Mix Modification of a Commercial Methicillin-Resistant Staphylococcus aureus PCR Assay▿

    Munson, Erik; Block, Timothy; Voegeli, Janet T.; Hryciuk, Jeanne E.; Schell, Ronald F.

    2009-01-01

    The expense inherent to molecular diagnostics may be an overriding concern for a variety of clinical laboratories in the development of PCR-based methicillin-resistant Staphylococcus aureus (MRSA) active surveillance programs. BD GeneOhm MRSA assay master mix was reconstituted, aliquoted into SmartCycler tubes in 25-μl volumes, and frozen at −70°C. One hundred percent of archival nasal swab lysates yielded the expected PCR results when incubated in master mix frozen for 1, 2, 3, and 4 weeks. ...

  11. Intensive Therapy with Ceftobiprole Medocaril of Experimental Foreign-Body Infection by Methicillin-Resistant Staphylococcus aureus

    Vaudaux, Pierre; Gjinovci, Asllan; Bento, Manuela; Li, Dongmei; Schrenzel, Jacques; Lew, Daniel P.

    2005-01-01

    The therapeutic activity of ceftobiprole medocaril, the water-soluble prodrug of ceftobiprole, was compared to that of vancomycin in a rat tissue cage model of chronic methicillin-resistant Staphylococcus aureus (MRSA) foreign-body infection. The MICs and MBCs of ceftobiprole and vancomycin in Mueller-Hinton broth for strain MRGR3 were 1 and 4 and 1 and 2 μg/ml, respectively. In vitro elimination rates of strain MRGR3 of 4 and 8 μg/ml of ceftobiprole or vancomycin were equivalent. After 2 wee...

  12. Label-free, electrochemical detection of methicillin-resistant staphylococcus aureus DNA with reduced graphene oxide-modified electrodes

    Wang, Zhijuan

    2011-05-01

    Reduced graphene oxide (rGO)-modified glassy carbon electrode is used to detect the methicillin-resistant Staphylococcus aureus (MRSA) DNA by using electrochemical impedance spectroscopy. Our experiments confirm that ssDNA, before and after hybridization with target DNA, are successfully anchored on the rGO surface. After the probe DNA, pre-adsorbed on rGO electrode, hybridizes with target DNA, the measured impedance increases dramatically. It provides a new method to detect DNA with high sensitivity (10-13M, i.e., 100 fM) and selectivity. © 2011 Elsevier B.V.

  13. The bactericidal effect of 470 nm light and hyperbaric oxygen on methicillin-resistant Staphylococcus aureus (MRSA)

    Bumah, Violet Vakunseh; Whelan, Harry Thomas; Masson-Meyers, Daniela Santos; Quirk, Brendan; Buchmann, Ellen; Enwemeka, Chukuka Samuel

    2015-01-01

    It has been shown that, in vitro, hyperbaric oxygen (HBO) suppresses 28% bacterial growth, while 470 nm blue light alone suppresses up to 92% methicillin resistant Staphylococcus aureus (MRSA) in one application in vitro. Therefore, we determined if combined 470 nm light (55 J/cm2) and HBO will yield 100% bacterial suppression in experimental simulation of mild, moderate or severe MRSA infection. We cultured MRSA at 3×106, 5×106, 7×106, 8×106 or 12×106 CFU/ml and treated each concentration in...

  14. Prevalence of nasal carriage of methicillin-resistant Staphylococcus aureus in children with diabetes mellitus: Trends between 2005 and 2013.

    Karadag-Oncel, Eda; Gonc, Nazli; Altay, Ozlem; Cengiz, Ali Bulent; Ozon, Alev; Pinar, Ahmet; Ceyhan, Mehmet; Alikasifoglu, Ayfer; Akyon, Yakut; Kandemir, Nurgun; Ozsurekci, Yasemin; Kara, Ates

    2015-09-01

    The aim of this prospective study was to establish the methicillin-resistant Staphylococcus aureus (MRSA) colonization rates in pediatric outpatients with type 1 diabetes mellitus, while also evaluating changes in colonization rates over time. There was no significant difference between 2005 and 2013 patients in terms of demographic and clinical findings. MRSA colonization rates were 0.7% (in 101 patients) and 0.9% (in 134 patients) (P = .84). Although increased MRSA colonization has become a significant problem worldwide, it does not seem to be a major issue in our diabetic outpatient population. PMID:26050099

  15. Disorganization of cell division of methicillin-resistant Staphylococcus aureus by methanolic extract from Phyllanthus columnaris stem bark

    Adnalizawati, A. Siti Noor; Nazlina, I.; Yaacob, W. A.

    2013-11-01

    The in vitro activity of methanolic extract from Phyllanthus columnaris stem bark was studied against Methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300 and MRSA BM1 (clinical strain) using time-kill curves in conjunction with scanning and transmission electron microscopy. The extract showed more markedly bactericidal activity in MRSA BM1 clinical strain within less than 4 h by 6.25-12.5 mg/mL and within 6 h by 1.56 mg/mL. Scanning electron microscopy of MRSA BM1 revealed distortion of cell whilst transmission electron microscopy revealed disruption in cell wall division.

  16. Disorganization of cell division of methicillin-resistant Staphylococcus aureus by methanolic extract from Phyllanthus columnaris stem bark

    The in vitro activity of methanolic extract from Phyllanthus columnaris stem bark was studied against Methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300 and MRSA BM1 (clinical strain) using time-kill curves in conjunction with scanning and transmission electron microscopy. The extract showed more markedly bactericidal activity in MRSA BM1 clinical strain within less than 4 h by 6.25-12.5 mg/mL and within 6 h by 1.56 mg/mL. Scanning electron microscopy of MRSA BM1 revealed distortion of cell whilst transmission electron microscopy revealed disruption in cell wall division

  17. Methicillin Resistant Staphylococcus aureus Carriage, Antibiotic Resistance and Molecular Pathogenicity among Healthy Individuals Exposed and Not Exposed to Hospital Environment

    Krishnamurthy, Veena; Renushri, Bhadravati Virupaksha; Nagaraj, Elkal Rajappa

    2014-01-01

    Background: Healthcare workers as well as healthy community-dwelling individuals may be colonised by methicillin-resistant Staphylococcus aureus (MRSA). Healthcare workers who carry MRSA may transmit it to patients, causing various nosocomial infections. Literature shows that the differences between MRSA isolated from healthcare settings and from community settings, with regard to multi-drug resistance (traditionally exhibited by the former) and possession of pvl genes (traditionally exhibited by the latter), is diminishing due to a large community reservoir and increasing influx of community harboured strains into the hospital. However, there is no literature on the current scenario in India. Aims and Objectives: This study examines the influence of exposure to hospital environment on MRSA carriage, antimicrobial resistance patterns of MRSA, and the presence of genes encoding five extracellular pathogenicity determinants (pvl, sea, seb, tsst-1 and hly a). Materials and Methods: Nasal, throat and palmar swabs were collected from 119 nursing students of the age group 18-23 years (exposed group) and 100 age matched pharmacy students (non-exposed group). S. aureus was identified and antibiogram obtained as per Clinical and Laboratory Standards Institute (CLSI) guidelines. MRSA was detected by cefoxitin disc diffusion test and by growth on oxacillin screen agar as per CLSI guidelines. Conventional PCR was performed for mecA, pvl, sea, seb, tsst-1 and hly a. Results: The differences in carrier rates, antibiotic resistance patterns and expression of extracellular pathogenicity determinants between MRSA isolates from the two study groups were not significant, and pvl was found in all the MRSA isolates. Conclusion: The nursing students carried MRSA strains similar to those carried by the non-exposed group. Our results suggest that healthcare workers could act as a link and transmit MRSA acquired from the community to patients. PMID:25177563

  18. Methicillin-Resistant Staphylococcus aureus nosocomial infection trends in Hospital universiti sains Malasia during 2002-2007

    Methicillin-resistant staphylococcus aureus (MRSA) is a major nosocomial pathogen that causes severe morbidity and mortality in many hospitals worldwide.The aim of the present study was to assess the burden of MRSA nosocomial infection,its association with factors of interest, and its antimicrobial susceptibility.This was a retrospective analysis of a database of all s aureus that were cultured from patients admitted to the defferent wards of hospital universiti sains malasia(HUSM) over a aperiod of 6 years.The MRSA infections rate was 10.0 Per 1000 hospital admissions.The incidence density rate of MRSA infections during the study period was 1.8 per 1000 patient-days,with annual rates ranging from 0.95 to 3.47 per 1000 patients-days.Duration of hospitalization,previous antibiotic use,and bedside invasive proceures of MRSa infections were found in orthopedic wards (25.3%) followed by surgical wards (18.2%) amd omtensive care units(ICU) (16.4%).All MRSA isolates were resistant to erythromycin (98.0%),co-trimoxazole (94.0%)and gentamicin (92.0%)clindamycin was the best antibiotic with only 6% resistance.All MRSA isolates were sensitive to vancomycin.The rate of the noscomial MRSA infection per 1000 admissions was higher than that in other studies.The three factors associated most signaficantly with acquired MRSA infections included duration of hospitalization,antibiotic use,and bedside invasive procedures.This study confirmed that vancomycin-resistant s aureus has not yet been established in HUSM (Author).

  19. Evaluation of Genotypic and Phenotypic Methods for Detection of Methicillin Resistant Staphylococcus aureus in a Tertiary Care Hospital of Eastern Odisha

    Panda, Rakesh Kumar; Mallick, Bandana; Chayani, Nirupama

    2016-01-01

    Introduction Methicillin resistant Staphylococcus aureus has emerged as an important pathogen in nosocomial and community acquired infections. Accurate and rapid identification of MRSA in clinical specimens is essential for timely decision of effective antimicrobial chemotherapy. Aim The present study was conducted to compare efficacy of four conventional phenotypic methods, with mec- A based polymerase chain reaction (PCR) for MRSA identification. Materials and Methods Methicillin resistance was determined in 200 S.aureus isolates by oxacillin disc diffusion, cefoxitin disc diffusion, Oxacillin Resistance Screening Agar and E-test. The results were compared with mec-A based PCR. Results Among 200 S.aureus isolates 62 (31%) were positive for mec-A gene by PCR. Cefoxitin disc diffusion, Oxacillin Resistance Screening Agar and E-test showed 100% specificity. Oxacillin disc diffusion had lowest sensitivity (82.5%) and specificity (98.5%) among all. The conventional methods take more time than PCR for diagnosing MRSA. Linezolid, Vancomycin & Dalfopristin were the highly sensitive drugs against MRSA isolates. Conclusion Cefoxitin disc diffusion, is rapid, simple and cheaper, hence can be used routinely as an alternative to PCR for detection of MRSA in resource constraint laboratories. PMID:27042463

  20. PREVALENCE AND ANTIMICROBIAL SUSCEPTIBILITY PATTERN OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS (MRSA ISOLATES IN A TERTIARY CARE HOSPITAL IN PUNJAB

    Satish

    2013-10-01

    Full Text Available ABSTRACT: BACKGROUND: Methicillin resistant Staphylococcus aureus (MRSA is an important cause of nosocomial infections worldwide. This prospective study was undertaken to know the prevalence of MRSA, to study antimicrobial susceptibility pattern and inducible clindamycin resistance in Staphylococcus aureus isolates obtained from the indoor patients of a tertiary care hospital in Punjab. MATERIALS AND METHODS : All the iso lates of Staphylococcus aureus obtained from various clinical specimens were identified by standard methods. MRSA was detected using 30ug cefoxitin disc by disc diffusion method as per CLSI guidelines, 2007. Each isolate was tested for other anti - staphyloc occal antibiotics by Kirby - Bauer disc diffusion method. Additionally, inducible clindamycin resistance was studied by disc induction test (D test. RESULTS : During a period of one year, a total of 252 isolates of Staphylococcus aureus were obtained. Eighty six (34.1% isolates were methicillin resistant Staphylococcus aureus (MRSA and the remaining 166 (65.8% isolates were methicillin sensitive Staphylococcus aureus (MSSA. MRSA isolates were significantly less sensitive to common anti - staphylococcal anti biotics as compared to MSSA isolates. However, MRSA isolates showed relatively better sensitivity to some of the antibiotics like netilmicin, levofloxacin, tetracycline and clindamycin. Susceptibility to ciprofloxacin was low in both MSSA (19.8% and MRSA (9.3%. None of the isolate of Staphylococcus aureus was resistant to vancomycin, linezolid and teicoplanin. Inducible clindamycin resistance was present in 17 (19.7% MRSA isolates as against 8 (4.8% MSSA isolates. CONCLUSION : Robust antimicrobial stewa rdship and strengthened infection control measures are required to prevent spread and reduce emergence of resistance

  1. Evaluation of ethyl N-(2-phenethyl) carbamate analogues as biofilm inhibitors of methicillin resistant Staphylococcus aureus.

    Stephens, Matthew D; Yodsanit, Nisakorn; Melander, Christian

    2016-07-12

    A small molecule library consisting of 45 compounds was synthesized based on the bacterial metabolite ethyl N-(2-phenethyl) carbamate. Screening of the compounds revealed a potent analogue capabale of inhibiting several strains of Methicillin Resistant S. aureus biofilms with low to moderate micromolar IC50 values. PMID:27341658

  2. Study of Antibiotic Resistance Pattern in Methicillin Resistant Staphylococcus Aureus with Special Reference to Newer Antibiotic.

    Kaur, Dardi Charan; Chate, Sadhana Sanjay

    2015-01-01

    The worldwide epidemic of antibiotic resistance is in danger of ending the golden age of antibiotic therapy. Resistance impacts on all areas of medicine, and is making successful empirical therapy much more difficult to achieve. Staphylococcus aureus demonstrates a unique ability to quickly respond to each new antibiotic with the development of a resistance mechanism, starting with penicillin, until the most recent, linezolid and daptomycin. Methicillin resistant S. aureus (MRSA) has become endemic today in hospitals worldwide. Resistance to the newer antimicrobial-agents - linezolid, vancomycin, teicoplanin, and daptomycin are been reported and also the fear of pandrug-resistance. This study was carried out to know the antimicrobial resistant pattern of MRSA to newer antibiotic, to know any isolates are extensively-drug resistant (XDR)/pandrug resistant (PDR), inducible macrolide-lincosamide streptogramin B (iMLSB), and mupirocin resistance. Thirty-six MRSA isolates resistant to the routinely tested antibiotic were further tested for list of antibiotic by a group of international experts. Isolates were tested for iMLSB and mupirocin resistance by the disk diffusion method. Of 385 MRSA, 36 (9.35%) isolates of MRSA were resistant to the routinely tested antibiotic. Among these 36 MRSA isolates, none of our isolates were XDR/PDR or showed resistant to anti-MRSA cephalosporins (ceftaroline), phosphonic acids, glycopeptides, glycylcyclines, and fucidanes. Lower resistance was seen in oxazolidinones (2.78%), streptogramins (5.56%), lipopeptide (5.56%). Thirty-four (94.44%) isolates showed constitutive MLSB (cMLSB) resistance and two (5.56%) iMLSB phenotypes. High- and low-level mupirocin resistance were seen in 13 (36.11%) and six (16.67%), respectively. In our study, none of our isolates were XDR or PDR. No resistance was observed to ceftaroline, telavancin, teicoplanin, and vancomycin; but the presence of linezolid resistance (1, 2.28%) and daptomycin resistance (2, 5

  3. Inhibition of methicillin-resistant Staphylococcus aureus by the compound Qingre granules

    YU Yi-yun; WANG Hong; ZHANG Shu-wen; WANG Bao-en

    2010-01-01

    Background The infection rate of methicillin-resistant Staphylococcus aureus (MRSA) is increasing yearly due to the overprescription of antibiotics. Traditional Chinese compound medicines are less inclined to induce bacterial resistance in the clinical setting because of their multi-acting mechanisms. However, most current research is limited to bacteriostasis in vitro using single extracts or formulations. Plasma pharmacology is an in vitro method, using what is called "medicine serum". The aim of this study was to investigate whether the medicine serum of compound Qingre granules (QRKL) alone or in combination with antibiotics may treat MRSA infection in the clinic.Methods An animal model of MRSA resistance was created by injecting rabbits with the standard strain of MRSA ATCC43300. Infected rabbits were treated with QRKL by intragastric administration. Sixty minutes after the last intragastric administration, serum was obtained from the rabbits by heart puncture to obtain what is termed "medicine serum". The minimum inhibitory concentration (MIC) of QRKL, medicine serum alone, or serum combined with antibiotics was assessed by agar dilution. Results were compared with the growth of sixteen isolates of MRSA. Results The MIC of QRKL to the standard strain ATCC43300 was 10.00 mg/ml. The MIC_(90)of vancomycin was 1.00 ug/ml, which, when combined with QRKL, dropped to 0.50 μg/ml. The MIC_(90) of cefuroxime alone was 512.00 μg/ml- This level also decreased to 256.00 μ g/ml when combined with QRKL. The addition of QRKL thus significantly reduced the MIC of both cefuroxime and vancomycin compared with antibiotics alone (P <0.01). The MIC90 of vancomycin with medicine serum decreased to 0.50 μ g/ml, and the MIC of vancomycin with medicine serum also descended compared with using vancomycin alone (P<0.01).Conclusions The growth of MRSA can be inhibited by QRKL or medicine serum of QRKL in vitro. The addition of QRKL results in increased sensitivity of MRSA to

  4. Methicillin-Resistant Staphylococcus aureus in Saarland, Germany: The Long-Term Care Facility Study

    Nillius, Dorothea; von Müller, Lutz; Wagenpfeil, Stefan; Klein, Renate; Herrmann, Mathias

    2016-01-01

    Background Multiresistant organisms pose a threat for patients and care recipients. Control interventions need to be tailored to region, the type of institution considered, and risk factors. The German state of Saarland is ideally suited to study colonisation epidemiology throughout its various health and care institutions. After conclusion of a large admission prevalence study in acute care hospitals, we now performed a methicillin-resistant Staphylococcus aureus (MRSA) point prevalence study in Saarland long term care facilities (LTCF), allowing for a direct comparison with respect of MRSA prevalence and associated risk factors between these two institutional types located within a confined region. Methodology and Principal Findings Of all LTCF of the region, 65/136 participated in the study performed between 09/2013 and 07/2014. Overall, complete microbiological specimen and questionnaires of 2,858 of 4,275 (66.8%) LTCF residents were obtained. 136/2,858 (4.8%) screened residents revealed MRSA carrier status. Multivariate risk factor analysis yielded ulcer/deep soft tissue infection, urinary tract catheter, and MRSA history with multiple MRSA decolonisation cycles to be independently associated with MRSA carrier status. Conclusion As already known from previous studies, colonisation with MRSA is common in LTCF residents even in an area with relatively low MRSA prevalence. This found prevalence can now be related to the acute care admission prevalence (2.2%) as well as to the admission prevalence in acute care geriatric departments (7.6%). The common clonal attribution (spa type) of MRSA isolates prevalent in the LTCF population as well as in the acute care admission population points towards a close relationship between both types of institutions. However, the ostensible absence of risk factors such as “previous hospitalisation” in conjunction with newly identified factors such as “multiple decolonisation cycles” refers to MRSA colonisation risks

  5. The Effectiveness of Bacteriophages against Methicillin-Resistant Staphylococcus aureus ST398 Nasal Colonization in Pigs

    Duim, Birgitta; Fluit, Ad C; Carney, Jennifer; van Nes, Arie; Wagenaar, Jaap A

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an important colonizer in animals and an opportunistic pathogen in humans. In humans, MRSA can cause infections that might be difficult to treat because of antimicrobial resistance. The use of bacteriophages has been suggested as a potential approach for the control of MRSA colonization to minimize the—often occupational—exposure of humans. The aim of this study was to assess the efficacy of bacteriophage treatment on porcine nasal colonization with MRSA in vitro, in vivo, and ex vivo. The effectiveness of a bacteriophage combination of phage K*710 and P68 was assessed in vitro by incubating them with MRSA V0608892/1 (ST398) measuring the OD600 hourly. To study the in vivo effect, bacteriophages were administered in a gel developed for human application, which contain 109 plaque-forming units (pfu)/mL (K and P68 in a 19.25:1 ratio) for 5 days to piglets (N = 8) that were experimentally colonized with the MRSA strain. Eight piglets experimentally colonized were used as a negative control. The MRSA strain was also used to colonize porcine nasal mucosa explants and bacteriophages were applied to assess the ex vivo efficacy of treatment. Bacteriophages were effective in vitro. In vivo, sixteen piglets were colonized with MRSA but the number of CFU recovered after the application of the bacteriophages in 8 piglets was not reduced compared to the control animals (approx. 105 CFU/swab). In the ex vivo model, 108 CFU were used to establish colonization with MRSA; a reduction of colonization was not observed after application of bacteriophages. However, application of mupirocin both in vivo and ex vivo resulted in a near eradication of MRSA. In conclusion: i) The MRSA strain was killed in the presence of the bacteriophages phage K*710 and P68 in vitro. ii) Bacteriophages did not reduce porcine nasal colonization in vivo or ex vivo. Physiological in vivo and ex vivo conditions may explain these observations. Efficacy

  6. Heavy metal and disinfectant resistance genes among livestock-associated methicillin-resistant Staphylococcus aureus isolates.

    Argudín, M Angeles; Lauzat, Birgit; Kraushaar, Britta; Alba, Patricia; Agerso, Yvonne; Cavaco, Lina; Butaye, Patrick; Porrero, M Concepción; Battisti, Antonio; Tenhagen, Bernd-Alois; Fetsch, Alexandra; Guerra, Beatriz

    2016-08-15

    Livestock associated methicillin-resistant Staphylococcus aureus (LA-MRSA) has emerged in animal production worldwide. Most LA-MRSA in Europe belong to the clonal complex (CC) 398. The reason for the LA-MRSA emergence is not fully understood. Besides antimicrobial agents used for therapy, other substances with antimicrobial activity applied in animal feed, including metal-containing compounds might contribute to their selection. Some of these genes have been found in various novel SCCmec cassettes. The aim of this study was to assess the occurrence of metal-resistance genes among a LA-S. aureus collection [n=554, including 542 MRSA and 12 methicillin-susceptible S. aureus (MSSA)] isolated from livestock and food thereof. Most LA-MRSA isolates (76%) carried at least one metal-resistance gene. Among the LA-MRSA CC398 isolates (n=456), 4.8%, 0.2%, 24.3% and 71.5% were positive for arsA (arsenic compounds), cadD (cadmium), copB (copper) and czrC (zinc/cadmium) resistance genes, respectively. In contrast, among the LA-MRSA non-CC398 isolates (n=86), 1.2%, 18.6% and 16.3% were positive for the cadD, copB and czrC genes, respectively, and none were positive for arsA. Of the LA-MRSA CC398 isolates, 72% carried one metal-resistance gene, and the remaining harboured two or more in different combinations. Differences between LA-MRSA CC398 and non-CC398 were statistically significant for arsA and czrC. The czrC gene was almost exclusively found (98%) in the presence of SCCmec V in both CC398 and non-CC398 LA-MRSA isolates from different sources. Regarding the LA-MSSA isolates (n=12), some (n=4) were also positive for metal-resistance genes. This study shows that genes potentially conferring metal-resistance are frequently present in LA-MRSA. PMID:27374912

  7. Complete genome sequence of Staphylococcus aureus strain M1, a unique t024-ST8-IVa Danish methicillin-resistant S. aureus clone

    Larner-Svensson, Hanna; Worning, Peder; Bartels, Mette;

    2013-01-01

    We report the genome sequence, in five contigs, of a methicillin-resistant Staphylococcus aureus isolate designated M1. This clinical isolate was from the index patient of a methicillin-resistant Staphylococcus aureus (MRSA) outbreak in Copenhagen, Denmark, that started in 2003. This strain is...

  8. Fermentation of Propionibacterium acnes, a commensal bacterium in the human skin microbiome, as skin probiotics against methicillin-resistant Staphylococcus aureus.

    Muya Shu

    Full Text Available Bacterial interference creates an ecological competition between commensal and pathogenic bacteria. Through fermentation of milk with gut-friendly bacteria, yogurt is an excellent aid to balance the bacteriological ecosystem in the human intestine. Here, we demonstrate that fermentation of glycerol with Propionibacterium acnes (P. acnes, a skin commensal bacterium, can function as a skin probiotic for in vitro and in vivo growth suppression of USA300, the most prevalent community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA. We also promote the notion that inappropriate use of antibiotics may eliminate the skin commensals, making it more difficult to fight pathogen infection. This study warrants further investigation to better understand the role of fermentation of skin commensals in infectious disease and the importance of the human skin microbiome in skin health.

  9. First Reported Case of Methicillin-Resistant Staphylococcus aureus Vertebral Osteomyelitis with Multiple Spinal and Paraspinal Abscesses Associated with Acupuncture

    Sandeep Singh Lubana

    2015-01-01

    Full Text Available Acupuncture is one of the oldest medical procedures in the world and originated in China about 2,000 years ago. Acupuncture is a form of complementary medicine and has gained popularity worldwide in the last few decades. It is mainly used for the treatment of chronic pain. Acupuncture is usually considered a safe procedure but has been reported to cause serious complications including death. It has been associated with transmission of many viruses and bacteria. Two cases of Methicillin-Resistant Staphylococcus aureus have been reported recently following acupuncture therapy. We are reporting a case of a 57-year-old Korean female who developed vertebral osteomyelitis and intraspinal and paraspinal abscesses as a complication of acupuncture. Blood cultures, skin lesion culture, and body fluid culture yielded Methicillin-Resistant Staphylococcus aureus (MRSA. Good anatomical and medical knowledge, good hygiene standards, and proper acupuncture techniques should be followed to prevent the complications. Acupuncturists should consistently review the infection control guidelines to acupuncture. This case should raise awareness of such condition and hazards of presumably benign procedures such as acupuncture.

  10. Identification of methicillin-resistant Staphylococcus aureus within the Nation’s Veterans Affairs Medical Centers using natural language processing

    Jones Makoto

    2012-07-01

    Full Text Available Abstract Background Accurate information is needed to direct healthcare systems’ efforts to control methicillin-resistant Staphylococcus aureus (MRSA. Assembling complete and correct microbiology data is vital to understanding and addressing the multiple drug-resistant organisms in our hospitals. Methods Herein, we describe a system that securely gathers microbiology data from the Department of Veterans Affairs (VA network of databases. Using natural language processing methods, we applied an information extraction process to extract organisms and susceptibilities from the free-text data. We then validated the extraction against independently derived electronic data and expert annotation. Results We estimate that the collected microbiology data are 98.5% complete and that methicillin-resistant Staphylococcus aureus was extracted accurately 99.7% of the time. Conclusions Applying natural language processing methods to microbiology records appears to be a promising way to extract accurate and useful nosocomial pathogen surveillance data. Both scientific inquiry and the data’s reliability will be dependent on the surveillance system’s capability to compare from multiple sources and circumvent systematic error. The dataset constructed and methods used for this investigation could contribute to a comprehensive infectious disease surveillance system or other pressing needs.

  11. Molecular characterisation of methicillin-susceptible and methicillin-resistant Staphylococcus aureus in inpatients and outpatients in Bosnia and Herzegovina.

    Uzunović-Kamberović, Selma; Rijnders, Michelle I A; Stobberingh, Ellen E; Ibrahimagić, Amir; Kamberović, Farah; Ille, Tatjana

    2013-01-01

    The aim of this study was to investigate the genetic background of methicillin-susceptible (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) obtained from clinical specimens of inpatients and outpatients. Methicillin resistance was confirmed by the presence of the mecA gene by PCR. The genetic characterisation was performed using spa typing and the algorithm based upon repeat pattern (BURP). Staphylococcus aureus was isolated from 68 and 79 inpatient and outpatient samples, 31 (46 %) and 14 (18 %) of which were MRSA, respectively. Among 37 inpatients and 65 outpatients with MSSA, 22 and 38 spa types were clustered into seven and eight spa-CCs, respectively. The main MSSA spa-CC of inpatients and outpatients was spa-CC015 (multilocus sequence typing (MLST) CC45). Most MRSA were associated with spa-CC355/595 (MLST CC152). MRSA-related background was found in 32 % of inpatients and 43 % of outpatients with MSSA, suggesting that MRSA did not arise from predominant MSSA clones. PMID:23053564

  12. Comparison of in vitro efficacy of linezolid and vancomycin by determining their minimum inhibitory concentrations against methicillin resistant Staphylococcus aureus (MRSA)

    Objectives: To compare the in vitro activities of vancomycin and linezolid against methicillin resistant Staphyloccus aureus in our set up to help in formulating a better empirical treatment and reduce the emergence of vancomycin resistant Staphylococcus aureus. Methods: The study was conducted over a period of 6 months(July 1, 2009 - Dec 1, 2009). Fifty Methicillin resistant Staphylococcus aureus isolated from the clinical isolates of Military Hospital Rawalpindi were subjected to the determination of Minimum inhibitory concentrations of linezolid and vancomycin using E-strips. Results: All the isolated organisms were uniformly susceptible to both the antibiotics. Vancomycin showed higher minimum inhibitory concentrations (MICs) as compared to linezolid MICs. Conclusion: This study suggests that linezolid and vancomycin have similar in vitro efficacy for methicillin resistant Staphyloccus aureus infections. (author)

  13. Comparative genomics and drug resistance of a geographic variant of ST239 methicillin-resistant Staphylococcus aureus emerged in Russia.

    Tatsuo Yamamoto

    Full Text Available Two distinct classes of methicillin-resistant Staphylococcus aureus (MRSA are spreading in hospitals (as hospital-acquired MRSA, HA-MRSA and in the community (as community-acquired MRSA, CA-MRSA. Multilocus sequence type (ST 239 MRSA, one of the most worldwide-disseminated lineages, has been noted as a representative HA-MRSA. Here, we isolated ST239 MRSA (spa type 3 [t037] and staphylococcal cassette chromosome mec [SCCmec] type III.1.1.1 and its novel variant with ST239/spa351 (t030/SCCmecIII.1.1.4 (SCCmecIII(R not only from hospitals but also from patients with urethritis in the community in Russia. The Russian variant (strain 16K possessed a hybrid genome consisting of CC8 and CC30, similar to the ST239/spa3/SCCmecIII.1.1.1 HA-MRSA (TW20 genome, but with marked diversity. The 16K' CC30 section had SCCmecIII(R carrying the dcs-carrying unit (which corresponded to the SCCmecIVc J3 joining region of ST30 CA-MRSA, lacked SCCmercury, and possessed a novel mobile element structure (MES16K carrying the ccrC-carrying unit (with the recombinase gene ccrC1 allele 3 and drug resistance tranposons. The Russian variant included strains with a high ability to transfer its multiple drug resistance by conjugation; e.g., for strain 16K, the transfer frequency of a chloramphenicol resistance plasmid (p16K-1 with 2.9 kb in size reached 1.4×10(-2, followed by Tn554 conjugative transfer at 3.6×l0(-4. The Russian variant, which has been increasing recently, included divergent strains with different plasmid patterns and pulsed field gel electrophoresis profiles. The data demonstrate the alternative nature of ST239 MRSA as CA-MRSA and also as a drug resistance disseminator, and its micro but dynamic evolution in Russia.

  14. Recombinations in staphylococcal cassette chromosome mec elements compromise the molecular detection of methicillin resistance in Staphylococcus aureus

    Hill-Cawthorne, Grant A.

    2014-06-27

    Clinical laboratories are increasingly using molecular tests for methicillin-resistant Staphylococcus aureus (MRSA) screening. However, primers have to be targeted to a variable chromosomal region, the staphylococcal cassette chromosome mec (SCCmec). We initially screened 726 MRSA isolates from a single UK hospital trust by recombinase polymerase amplification (RPA), a novel, isothermal alternative to PCR. Undetected isolates were further characterised using multilocus sequence, spa typing and whole genome sequencing. 96% of our tested phenotypically MRSA isolates contained one of the six orfX-SCCmec junctions our RPA test and commercially available molecular tests target. However 30 isolates could not be detected. Sequencing of 24 of these isolates demonstrated recombinations within the SCCmec element with novel insertions that interfered with the RPA, preventing identification as MRSA. This result suggests that clinical laboratories cannot rely solely upon molecular assays to reliably detect all methicillin-resistance. The presence of significant recombinations in the SCCmec element, where the majority of assays target their primers, suggests that there will continue to be isolates that escape identification. We caution that dependence on amplification-based molecular assays will continue to result in failure to diagnose a small proportion (?4%) of MRSA isolates, unless the true level of SCCmec natural diversity is determined by whole genome sequencing of a large collection of MRSA isolates. © 2014 Hill-Cawthorne et al.

  15. Antimicrobial resistance in methicillin susceptible and methicillin resistant Staphylococcus pseudintermedius of canine origin: literature review from 1980 to 2013.

    Moodley, Arshnee; Damborg, Peter; Nielsen, Søren Saxmose

    2014-07-16

    Staphylococcus pseudintermedius is a commensal and a common opportunistic pathogen causing mainly infections of the integumentary system in dogs. The recent emergence of multidrug-resistant S. pseudintermedius isolates, in particular methicillin-resistant strains (MRSP) is a threat to small animal health and highlights the need for antimicrobial resistance surveillance to detect trends and potentially perform timeous interventions. We systematically reviewed 202 published articles to investigate temporal changes in antimicrobial resistance in clinical and commensal S. pseudintermedius isolated from dogs in 27 countries between 1980 and 2013. Resistance to the most common antimicrobials tested for in published studies and important for the treatment of staphylococcal infections in dogs were assessed separately for methicillin resistant (MRSP) and methicillin susceptible (MSSP) isolates. Stratified by MSSP and MRSP, no significant increases in antimicrobial resistance were observed over time, except for the penicillinase-labile penicillins (penicillin and ampicillin) among MSSP. However, in recent years, a few studies have reported higher-level of resistance to amikacin, gentamicin and enrofloxacin amongst MSSP. The review highlights inconsistencies between studies as a result of several factors, for example the use of different antimicrobial susceptibility testing methods and interpretation criteria. We recommend that data on susceptibility in important companion animal pathogens are collected and presented in a more harmonized way to allow more precise comparison of susceptibility patterns between studies. One way to accomplish this would be through systematic surveillance either at the country-level or at a larger scale across countries e.g. EU level. PMID:24613081

  16. Recombinations in staphylococcal cassette chromosome mec elements compromise the molecular detection of methicillin resistance in Staphylococcus aureus.

    Grant A Hill-Cawthorne

    Full Text Available Clinical laboratories are increasingly using molecular tests for methicillin-resistant Staphylococcus aureus (MRSA screening. However, primers have to be targeted to a variable chromosomal region, the staphylococcal cassette chromosome mec (SCCmec. We initially screened 726 MRSA isolates from a single UK hospital trust by recombinase polymerase amplification (RPA, a novel, isothermal alternative to PCR. Undetected isolates were further characterised using multilocus sequence, spa typing and whole genome sequencing. 96% of our tested phenotypically MRSA isolates contained one of the six orfX-SCCmec junctions our RPA test and commercially available molecular tests target. However 30 isolates could not be detected. Sequencing of 24 of these isolates demonstrated recombinations within the SCCmec element with novel insertions that interfered with the RPA, preventing identification as MRSA. This result suggests that clinical laboratories cannot rely solely upon molecular assays to reliably detect all methicillin-resistance. The presence of significant recombinations in the SCCmec element, where the majority of assays target their primers, suggests that there will continue to be isolates that escape identification. We caution that dependence on amplification-based molecular assays will continue to result in failure to diagnose a small proportion (∼4% of MRSA isolates, unless the true level of SCCmec natural diversity is determined by whole genome sequencing of a large collection of MRSA isolates.

  17. Risk Factors for Infection and Colonization with Community-Associated Methicillin-Resistant Staphylococcus aureus in the Los Angeles County Jail: A Case-Control Study

    Maree, Cynthia L.; Eells, Samantha J.; Tan, Jennifer; Bancroft, Elizabeth A.; Malek, Mark; Harawa, Nina T; Lewis, Martha J.; Santana, Elaine; Miller, Loren G.

    2010-01-01

    Background. Community-associated methicillin-resistant Staphylococcus aureus (MRSA) infections and outbreaks occur in correctional facilities, such as jails and prisons. Spread of these infections can be extremely difficult to control. Development of effective prevention protocols requires an understanding of MRSA risk factors in incarcerated persons.

  18. First report on methicillin-resistant Staphylococcus aureus of Spa type T037, Sequence type 239, SCCmec type III/IIIA in Malaysia

    V. Neela (Vasanthakumari); H. Ghasemzadeh Moghaddam (Hamed); A.F. van Belkum (Alex); D. Horst-Kreft (Deborah); N.S. Mariana (Nor Shamsudin); E. Ghaznavi Rad (Ehsanollah)

    2010-01-01

    textabstractMethicillin-resistant Staphylococcus aureus (MRSA) from Malaysia were shown to possess staphylococcal cassette chromosome mec (SCCmec)-III and IIIA. Spa sequencing and multi-locus sequence typing (MLST) documented t037 and ST 239 (CC8) for 83.3% of the isolates. This confirms observation

  19. Development of a Multiplex PCR Method for Detection of the Genes Encoding 16S rRNA, Coagulase, Methicillin Resistance and Enterotoxins in Staphylococcus aureus

    A multiplex PCR method was developed for simultaneous detection of the genes encoding methicillin resistance (mecA), staphylococcal enterotoxins A, B and C (sea, seb and sec), coagulase (coa) and 16S rRNA. The primers for amplification of the 16S rRNA gene were specific for Staphylococcus spp., and ...

  20. Evaluation of ceftiofur and cefquinome for phenotypic detection of methicillin resistance in Staphylococcus aureus using disk diffusion testing and MIC-determinations

    Aarestrup, Frank Møller; Skov, R. L.

    2010-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) have emerged in animals. Testing 98 mecA negative and 71 mecA positive S. aureus we compared the usefulness of ceftiofur and cefquinome to cefoxitin, for detection of MRSA and found that these cephalosporins are not as efficient as cefoxitin....

  1. Population-Based Estimates of Methicillin-Resistant "Staphylococcus aureus" (MRSA) Infections among High School Athletes--Nebraska, 2006-2008

    Buss, Bryan F.; Mueller, Shawn W.; Theis, Max; Keyser, Alison; Safranek, Thomas J.

    2009-01-01

    Methicillin-resistant "Staphylococcus aureus" (MRSA) is an emerging cause of skin and soft-tissue infections among athletes. To determine statewide incidence among high school athletes, we surveyed all 312 Nebraska high schools regarding sport programs offered, program-specific participation numbers, number of athletes with physician-diagnosed…

  2. Surveillance of Physician-Diagnosed Skin and Soft Tissue Infections Consistent With Methicillin-Resistant "Staphylococcus aureus" (MRSA) among Nebraska High School Athletes, 2008-2012

    Buss, Bryan F.; Connolly, Susan

    2014-01-01

    Though historically confined to hospital settings, methicillin-resistant Staphylococcus aureus (MRSA) has received increasing attention in the wider community, particularly among athletes. A 2007-2008 investigation in Nebraska concluded that MRSA skin infections were an emerging problem among the state's student athletes. Statewide…

  3. Cloning and Occurrence of czrC, a Gene Conferring Cadmium and Zinc Resistance in Methicillin-Resistant Staphylococcus aureus CC398 Isolates

    Cavaco, L. M.; Hasman, H.; Stegger, M.; Andersen, P. S.; Skov, R.; Fluit, A. C.; Ito, T.; Aarestrup, F. M.

    2010-01-01

    We recently reported a phenotypic association between reduced susceptibility to zinc and methicillin resistance in Staphylococcus aureus CC398 isolates from Danish swine (F. M. Aarestrup, L. M. Cavaco, and H. Hasman, Vet. Microbiol. 142: 455-457, 2009). The aim of this study was to identify the gene

  4. Efficacy of quinupristin/dalfopristin versus vancomycin, alone or in combination with rifampicin, against methicillin-resistant Staphylococcus aureus in a rabbit arthritis model.

    Hamel, Antoine; Caillon, Jocelyne; Jacqueline, Cédric; Batard, Eric; Potel, Gilles

    2008-02-01

    We compared the efficacy of quinupristin/dalfopristin versus vancomycin, alone or in combination with rifampicin, in a rabbit model of methicillin-resistant Staphylococcus aureus-induced arthritis. Vancomycin, alone or in combination with rifampicin, and quinupristin/dalfopristin+rifampicin were significantly more effective than quinupristin/dalfopristin alone. PMID:18006281

  5. Increasing Prevalence of Methicillin-Resistant Staphylococcus aureus Causing Nosocomial Infections at a University Hospital in Taiwan from 1986 to 2001

    Hsueh, Po-Ren; Teng, Lee-Jene; Chen, Wen-Hwei; Pan, Huei-Ju; Chen, Mei-Lin; Chang, Shan-Chwen; Luh, Kwen-Tay; Lin, Fang-Yue

    2004-01-01

    A rapid emergence of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection (from 26.3% in 1986 to 77% in 2001) was found. The susceptibility of 200 nonduplicate blood isolates of MRSA and 100 MRSA isolates causing refractory bacteremia to 22 antimicrobial agents disclosed that glycopeptides, quinupristin-dalfopristin, and linezolid remained the most active agents.

  6. DNA microarray genotyping and virulence and antimicrobial resistance gene profiling of methicillin-resistant Staphylococcus aureus bloodstream isolates from renal patients.

    McNicholas, Sinead

    2012-02-01

    Thirty-six methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from renal patients were genetically characterized by DNA microarray analysis and spa typing. The isolates were highly clonal, belonging mainly to ST22-MRSA-IV. The immune evasion and enterotoxin gene clusters were found in 29\\/36 (80%) and 33\\/36 (92%) isolates, respectively.

  7. 5 years of experience implementing a methicillin-resistant Staphylococcus aureus search and destroy policy at the largest university medical center in the Netherlands

    M.C. Vos (Margreet); M.D. Behrendt (Myra); D.C. Melles (Damian); F.P.N. Mollema (Femke); W. de Groot (Woutrinus); G. Parlevliet (Gerard); A. Ott (Alewijn); D. Horst-Kreft (Deborah); A.F. van Belkum (Alex); H.A. Verbrugh (Henri)

    2009-01-01

    textabstractOBJECTIVE: To evaluate the effectiveness of a rigorous search and destroy policy for controlling methicillin-resistant Staphylococcus aureus (MRSA) infection or colonization. DESIGN: Hospital-based observational follow-up study. SETTING: Erasmus University Medical Center Rotterdam, a 1,2

  8. DNA microarray genotyping and virulence and antimicrobial resistance gene profiling of methicillin-resistant Staphylococcus aureus bloodstream isolates from renal patients.

    McNicholas, Sinead

    2011-12-01

    Thirty-six methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from renal patients were genetically characterized by DNA microarray analysis and spa typing. The isolates were highly clonal, belonging mainly to ST22-MRSA-IV. The immune evasion and enterotoxin gene clusters were found in 29\\/36 (80%) and 33\\/36 (92%) isolates, respectively.

  9. Prevalence of USA300 Colonization or Infection and Associated Variables During an Outbreak of Community-Associated Methicillin-Resistant Staphylococcus aureus in a Marginalized Urban Population

    Mark Gilbert

    2007-01-01

    Full Text Available BACKGROUND: In 2004, an outbreak of the USA300 strain of methicillin-resistant Staphylococcus aureus (MRSA was identified in persons with histories of homelessness, illicit drug use or incarceration in the Calgary Health Region (Calgary, Alberta. A prevalence study was conducted to test the hypotheses for factors associated with USA300 colonization or infection.

  10. Evaluation of Two New Chromogenic Media, CHROMagar MRSA and S. aureus ID, for Identifying Staphylococcus aureus and Screening Methicillin-Resistant S. aureus

    Hedin, Göran; Fang, Hong

    2005-01-01

    Thirty-nine methicillin-resistant Staphylococcus aureus (MRSA) isolates with diverse genetic backgrounds and two reference strains were correctly identified as S. aureus on CHROMagar MRSA and S. aureus ID media. Growth inhibition on CHROMagar MRSA was noted. A combination of cefoxitin disk and S. aureus ID was found suitable for rapid MRSA screening.

  11. Cost Comparison of Linezolid Versus Vancomycin for Treatment of Complicated Skin and Skin-Structure Infection Caused by Methicillin-Resistant Staphylococcus aureus in Quebec

    Martine Pettigrew

    2012-01-01

    Full Text Available BACKGROUND: In Canada, complicated skin and skin-structure infection (cSSSI caused by methicillin-resistant Staphylococcus aureus (MRSA is usually treated with antibiotics in hospital, with a follow-up course at home for stable patients. The cost implications of using intravenous and oral linezolid instead of intravenous vancomycin in Canadian clinical practice have not been examined.

  12. Comparison of Chromogenic Media to BD GeneOhm Methicillin-Resistant Staphylococcus aureus (MRSA) PCR for Detection of MRSA in Nasal Swabs▿

    Bischof, Larry J.; Lapsley, Linda; Fontecchio, Karen; Jacosalem, Dollie; Young, Carol; Hankerd, Rosemary; Newton, Duane W.

    2009-01-01

    To select a method for detecting methicillin-resistant Staphylococcus aureus (MRSA) in nasal swabs, we compared BD GeneOhm MRSA PCR and various culture media (mannitol salt agar with cefoxitin, MRSASelect, CHROMagar MRSA, and Spectra MRSA). While PCR detection of MRSA was more rapid, MRSASelect and Spectra MRSA demonstrated performance equivalent to that of PCR with maximal detection at 24 h.

  13. Staphylococcus aureus resistentes à meticilina: disseminação emergente na comunidade Methicillin-resistant Staphylococcus aureus: emerging community dissemination

    Luciane Cristina Gelatti

    2009-10-01

    Full Text Available Staphylococcus aureus é uma bactéria responsável por uma ampla variedade de enfermidades infecciosas. A grande preocupação está relacionada, principalmente, com os isolados resistentes à meticilina (MRSA, que, tradicionalmente, estavam limitados aos hospitais. Nos últimos anos, infecções causadas por MRSA associadas ou adquiridas na comunidade (CA-MRSA têm sido relatadas com frequência crescente em todo o mundo. Algumas características fenotípicas e genéticas são distintas entre a forma de infecção hospitalar e a comunitária. Atualmente, verifica-se um perfil de sensibilidade reduzido para diferentes antimicrobianos; sendo assim faz-se necessário um alerta aos profissionais da saúde, particularmente aos dermatologistas, para a importância da distinção entre as formas de infecções, evitando uma terapia empírica incorreta e sem sucesso.Staphylococcus aureus is responsible for a broad variety of infectious diseases. The main concern is about methicillin-resistant isolates (MRSA, which are usually limited to hospitals. In recent years, community associated or acquired MRSA infections (CA-MRSA have been frequently reported and emerged in the world. Some phenotypic and genotypic characteristics are distinct between hospital and community infection. Currently, there is reduced sensibility profile to different antimicrobials, reason why it is necessary to issue an alert to healthcare professionals, dermatologists in particular, about the importance of knowing the differences between the infections, preventing wrong and unsuccessful empirical therapy.

  14. Random amplified polymorphic DNA assay is less discriminant than pulsed-field gel electrophoresis for typing strains of methicillin-resistant Staphylococcus aureus.

    Saulnier, P; Bourneix, C; Prévost, G; Andremont, A

    1993-04-01

    Twenty-six strains of methicillin-resistant Staphylococcus aureus with different pulsed-field gel electrophoresis fingerprints were tested by random amplified polymorphic DNA assay with three primers, resulting in 15 to 20 different random amplified polymorphic DNA fingerprints. By summing the results for the three primers, the number of different fingerprints increased to 25, but two strains could not be differentiated. We conclude that pulsed-field gel electrophoresis remains the best method of typing methicillin-resistant S. aureus strains. PMID:8463406

  15. Antimicrobial resistance in methicillin susceptible and methicillin resistant Staphylococcus pseudintermedius of canine origin

    Moodley, Arshnee; Damborg, Peter Panduro; Nielsen, Søren Saxmose

    2014-01-01

    from dogs in 27 countries between 1980 and 2013. Resistance to the most common antimicrobials tested for in published studies and important for the treatment of staphylococcal infections in dogs were assessed separately for methicillin resistant (MRSP) and methicillin susceptible (MSSP) isolates...... are collected and presented in a more harmonized way to allow more precise comparison of susceptibility patterns between studies. One way to accomplish this would be through systematic surveillance either at the country-level or at a larger scale across countries e.g. EU level....

  16. Studies of the in Vitro Antibacterial Activities of Several Polyphenols against Clinical Isolates of Methicillin-Resistant Staphylococcus aureus

    Yanli Su

    2014-08-01

    Full Text Available In this study, we report the antibacterial activities of six polyphenols (i.e., luteolin, quercetin, scutellarin, apigenin, chlorogenic acid, and resveratrol against 29 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA, and in vitro antibacterial activities of two-drug combinations. All of the MRSA strains evaluated were clinical isolates from patients with MRSA bacteremia. The antibacterial activities were determined by agar dilution method, and the two-drug antibacterial activities were determined by the checkerboard agar dilution method. It was found that luteolin, quercetin and resveratrol show obvious antibacterial activities against MRSA, and the results of two-drug antibacterial activity show either synergy or additivity, without evidences of antagonistic effects.

  17. The effectiveness of methicillin-resistant Staphylococcus aureus colonisation screening in asymptomatic healthcare workers in an Irish orthopaedic unit.

    Edmundson, S P

    2012-01-31

    Methicillin-resistant Staphylococcus aureus (MRSA) infections are associated with increased mortality, costs and length of stay compared to non-MRSA infections. This observational 4-year study analyses the impact of screening and treating orthopaedic healthcare workers for MRSA colonisation. A total of 1,011 swabs were taken from 566 healthcare workers. Positive healthcare workers were treated with topical mupirocin to both anterior nares. The prevalence of MRSA colonisation on initial testing was 4.77%. The rate of positive MRSA colonisation of those tested on more than one occasion fell from 5.88% to 2.71% (p = 0.055) on subsequent screening. All healthcare workers receiving treatment were successfully cleared of colonisation; however, some required more than one course of treatment. These results show that there could be a role for screening and treating orthopaedic staff for MRSA colonisation as part of a strategy to reduce the prevalence of MRSA infections in orthopaedic units.

  18. Transmission of methicillin-resistant Staphylococcus aureus infection through solid organ transplantation: confirmation via whole genome sequencing.

    Wendt, J M; Kaul, D; Limbago, B M; Ramesh, M; Cohle, S; Denison, A M; Driebe, E M; Rasheed, J K; Zaki, S R; Blau, D M; Paddock, C D; McDougal, L K; Engelthaler, D M; Keim, P S; Roe, C C; Akselrod, H; Kuehnert, M J; Basavaraju, S V

    2014-11-01

    We describe two cases of donor-derived methicillin-resistant Staphylococcus aureus (MRSA) bacteremia that developed after transplantation of organs from a common donor who died from acute MRSA endocarditis. Both recipients developed recurrent MRSA infection despite appropriate antibiotic therapy, and required prolonged hospitalization and hospital readmission. Comparison of S. aureus whole genome sequence of DNA extracted from fixed donor tissue and recipients' isolates confirmed donor-derived transmission. Current guidelines emphasize the risk posed by donors with bacteremia from multidrug-resistant organisms. This investigation suggests that, particularly in the setting of donor endocarditis, even a standard course of prophylactic antibiotics may not be sufficient to prevent donor-derived infection. PMID:25250717

  19. Antibacterial activity of Rosmarinus officinalis L. alone and in combination with cefuroxime against methicillin-resistant Staphylococcus aureus

    Naser Jarrar; Awni Abu-Hijleh; Kamel Adwan

    2010-01-01

    Objective: To determine the antimicrobial activity of rosemary (Rosmarinus officinalis L.) and to investigate the synergistic effects of this extract combined with ceforuxime against methicillin-resistantStaphylococcus aureus (MRSA).Methods: The inhibitory and bactericidal activities of rosemary ethanol extract, alone and in combination with cefuroxime, were studied.Results: The minimum inhibitory concentrations (MICs) of the ethanol extract of rosemary were in the range of 0.39-3.13 mg/mL. The minimum bactericidal concentrations (MBCs) were usually equal to or double that MICs. The antimicrobial activity of combinations of the ethanol extract of rosemary and cefuroxime indicated their synergistic effects against all MRSAs.Conclusions: The present work clearly demonstrates that rosemary has a key role in the elevation of susceptibility toβ-lactams.

  20. Vertebral osteomyelitis caused by vancomycin-tolerant methicillin-resistant Staphylococcus aureus bacteremia: Experience with teicoplanin plus fosfomycin combination therapy.

    Lee, Wen-Sen; Chen, Yen-Chuo; Chen, Hung-Ping; Chen, Tso-Hsiao; Cheng, Chung-Yi

    2016-08-01

    An 85-year-old female presented with fever and consciousness disturbance for 3 days. The patient's blood culture subsequently revealed persistent methicillin-resistant Staphylococcus aureus (MRSA) bacteremia despite the administration of vancomycin or teicoplanin monotherapy. Gallium inflammation scan and magnetic resonance image of the spine disclosed osteomyelitis and discitis at the level of L4-5. Surgical debridement was not feasible in this debilitated patient. Because of the creeping minimal inhibitory concentration of vancomycin of the causative isolate (1.5 μg/mL) and clinical failure with glycopeptide monotherapy, we changed the antibiotic therapy to a fosfomycin and teicoplanin combination therapy. The patient showed improved clinical response in terms of her enhanced consciousness as well as subsidence of persisted bacteremia. Despite the potential side effects of fosfomycin (such as diarrhea and hypernatremia), it combined with a glycopeptide may be an alternative therapy for invasive refractory MRSA infections. PMID:24269007

  1. Optimizing Host-Pathogen In-Flight Assays for C.Elegans and Methicillin-Resistant Staphylococcus Aureus

    Hammond, Timothy G.; Birdsall, Holly H.; Hammond, Jeffrey S.; Allen, Patricia L.

    2013-02-01

    This study addresses controls for an assay of bacterial virulence that has been optimized for space flight studies. Caenorhabditis elegans (C. elegans) worms ingest microorganisms, but are also killed by virulent bacteria. Virulence is assessed by the number of bacteria surviving in co-culture with C. elegans , as measured by optical density at 620 nm. Co -cultures of Methicillin-resistant Staphylococcus aureus (MRSA) with C. elegans have a higher OD620 than MRSA grown alone, which could reflect debris from dead worms and/or enhanced growth of the MRSA in response to worm-derived factors. The use of media conditioned by pre-incubation with worms demonstrated the presence of temperature-stable factors that change MRSA growth in a strain-dependent manner. Some sources of deionized water contain an undefined antibacterial activity present in conditioned, but not fresh untreated media.

  2. Carriage frequency, diversity and methicillin resistance of Staphylococcus aureus in Danish small ruminants

    Eriksson, Jacob; Gongora, Carmen Espinosa; Stamphøj, Inga;

    2013-01-01

    The ecology of Staphylococcus aureus in animals has recently gained attention by the research community due to the emergence of livestock-associated methicillin-resistant strains (MRSA). We investigated carriage frequency and clonal diversity of S. aureus in 179 sheep and 17 goats in Denmark using...... spa typing and MLST. S. aureus was detected in 74 sheep (41%) and 11 goats (64%). The isolates belonged to 26 spa types (including six novel spa types) and 12 STs (including three novel STs). The most common lineage was ST133, which was found in 65% sheep and 55% goats. MRSA was found in three animals...... study provides novel data about the occurrence of S. aureus in small ruminants, revealing high carriage frequency and diversity in these animals. The finding of mecC in ovine ST130 isolates suggests that sheep may be a reservoir of this new emerging MRSA clone of suspected animal origin. Inclusion of...

  3. Characterization of methicillin-resistant Staphylococcus aureus isolates from pig carcasses in Hong Kong

    Ho, J.; O'Donoghue, M.; Guardabassi, Luca;

    2012-01-01

    This study describes the isolation and characterization of methicillin-resistant Staphylococcus aureus (MRSA) from slaughtered pigs sampled from local markets in Hong Kong. The nares of 400 slaughtered pigs were cultured and MRSA isolates characterized for the presence of antibiotic-resistance...... predominant, with only 5/170 isolates displaying closely related types (t4474, t1939, t2922 and t5390). PFGE with sma1 and MLST confirmed the strains as ST9. Most isolates were multidrug resistant. Tetracycline resistance (97%) was mainly attributable to tet(K) with only 3% of isolates additionally harbouring...... tet(M). Resistance to erythromycin (89%) and chloramphenicol (71%) was associated with the presence of erm(C), and fex(A), respectively. No strains carried cfr and there was no resistance to linezolid, although minimum inhibitory concentration (MICs) were close to the resistance break point...

  4. A genomic portrait of the emergence, evolution, and global spread of a methicillin-resistant Staphylococcus aureus pandemic

    Holden, Matthew T G; Hsu, Li-Yang; Kurt, Kevin;

    2013-01-01

    to analyze the genome sequences for 193 S. aureus isolates, we were able to show that the current pandemic population of EMRSA-15 descends from a health-care-associated MRSA epidemic that spread throughout England in the 1980s, which had itself previously emerged from a primarily community......The widespread use of antibiotics in association with high-density clinical care has driven the emergence of drug-resistant bacteria that are adapted to thrive in hospitalized patients. Of particular concern are globally disseminated methicillin-resistant Staphylococcus aureus (MRSA) clones...... that cause outbreaks and epidemics associated with health care. The most rapidly spreading and tenacious health-care-associated clone in Europe currently is EMRSA-15, which was first detected in the UK in the early 1990s and subsequently spread throughout Europe and beyond. Using phylogenomic methods...

  5. Antimicrobial activity and synergism of Sami-Hyanglyun-Hwan with ciprofloxacin against methicillin-resistant Staphylococcus aureus

    Jang-Gi; Choi; Ji-Young; Choi; Su-Hyun; Mun; Ok-Hwa; Kang; Preeti; Bharaj; Dong-Won; Shin; Myong-Soo; Chong; Dong-Yeul; Kwon

    2015-01-01

    Objective: To investigate the antibacterial activity of SHHextracted with either water or ethanol against methicillin-resistant Staphylococcus aureus(MRSA) and combinatory antimicrobial effect with ciprofloxacin(CIP) by time kill assay and checkerboard dilution test. Methods: The antibacterial activity determined by broth dilution method indicated that the antibacterial activity of Sami-Hyanglyun-Hwan(SHH) water extract(SHHW) and SHH ethanol extract(SHHE) ranged from 250 to 2000 μg/m L and 125 to 1000 μg/m L against MRSA, respectively. Results: In the checkerboard method, the combinations of SHHE with CIP had a partial synergistic or synergistic effect against MRSA. The time-kill curves showed that a combined SHHE and CIP treatment reduced the bacterial counts dramatically after 24 h. Conclusions: The present study demonstrates the therapeutic ability of SHHE against MRSA infections.

  6. Radiolabeling, biological evaluation and molecular docking of delafloxacin. A novel methicillin-resistant Staphylococcus aureus infection radiotracer

    Labeling of delafloxacin with technetium-99m (99mTc) and its characterization in terms of in vitro stability and in vitro binding with methicillin-resistant Staphylococcus aureus (MRSA) were explored. Optimum amounts of reactants were 2.5 mg delafloxacin, 125 µg stannous chloride dihydrate and ∼125 MBq pertechnetate. The 99mTc-delafloxacin was stable up to 6 h. Molecular modeling and docking studies showed that the complex will stabilize the DNA-topoisomerase IIA cleavage complex and inhibit strands separation. The in vivo evaluation showed highest specific accumulation in the live MRSA model (8 %) compared to other models. All gathered data supported the usefulness of 99mTc-delafloxacin as a MRSA radiotracer. (author)

  7. In Vitro Antibacterial and Antibiotic Resistance Modifying Effect of Bioactive Plant Extracts on Methicillin-Resistant Staphylococcus epidermidis

    Romana Chovanová

    2013-01-01

    Full Text Available The crude extracts of plants from Asteraceae and Lamiaceae family and essential oils from Salvia officinalis and Salvia sclarea were studied for their antibacterial as well as antibiotic resistance modifying activity. Using disc diffusion and broth microdilution assays we determined higher antibacterial effect of three Salvia spp. and by evaluating the leakage of 260 nm absorbing material we detected effect of extracts and, namely, of essential oils on the disruption of cytoplasmic membrane. The evaluation of in vitro interactions between plant extracts and oxacillin described in terms of fractional inhibitory concentration (FIC indices revealed synergistic or additive effects of plant extracts and clearly synergistic effects of essential oil from Salvia officinalis with oxacillin in methicillin-resistant Staphylococcus epidermidis.

  8. Relatedness of strains of methicillin-resistant coagulase-negative Staphylococcus colonizing hospital personnel and producing bacteremias in a neonatal intensive care unit.

    Patrick, C H; John, J F; Levkoff, A H; Atkins, L M

    1992-11-01

    The emergence of methicillin-resistant coagulase-negative Staphylococcus as a major bacterial pathogen in neonatal intensive care units has stimulated interest in the epidemiology of spread of the organism. During a 12-month "epidemic" of bacteremias with methicillin-resistant coagulase-negative Staphylococcus we compared the characteristics of bacteremic and personnel nasally-carried strains by traditional and biomolecular methods. Sixty-two percent of neonatal intensive care unit nurses were colonized with methicillin-resistant coagulase-negative Staphylococcus with similar speciation to bacteremic strains. Inspection of plasmid profiles revealed a moderate degree of similarity between bacteremic and colonizing strains although genomic DNA restriction patterns showed diversity. Ribotype patterns were highly conserved (90%) in personnel strains. A 2.6-kilobase plasmid DNA probe hybridized to similarly sized plasmids and larger plasmids in one-half of the strains. We hypothesize that related methicillin-resistant strains may be transferred among personnel and neonates in the neonatal intensive care unit. Epidemiologic studies of coagulase-negative staphylococci should consider multiple molecular techniques to relate strains. PMID:1454435

  9. In-vitro activity of tigecycline against methicillin-resistant Staphylococcus aureus Isolated from wounds of burn patients in Tripoli-Libya

    Abdulazziz Zorgani; Omar Elahmer; Hisham Ziglam; Khalifa Sifaw Ghenghesh

    2012-01-01

    Objectives: Tigecycline is a new glycylcycline group antibiotic with broad-spectrum activity. In the present study wereport on in vitro activity of tigecycline as well as the comparator antimicrobials linezolid and quinupristin/dalfopristinagainst methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin resistant Staphylococcus aureus (MRSA)strains isolated from burn wounds in Tripoli-Libya.Materials and methods: Included in the study 155 MSSA and 144 MRSA isolates from wounds of ...

  10. In-vitro Activity of Tigecycline against Methicillin-Resistant Staphylococcus aureus Isolated from Wounds of Burn Patients in Tripoli-Libya

    Zorgani, Abdulazziz; Elahmer, Omar; Ziglam, Hisham; Ghenghesh, Khalifa Sifaw

    2012-01-01

    Objectives: Tigecycline is a new glycylcycline group antibiotic with broad-spectrum activity. In the present study we report on in vitro activity of tigecycline as well as the comparator antimicrobials linezolid and quinupristin/dalfopristin against methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin resistant Staphylococcus aureus (MRSA) strains isolated from burn wounds in Tripoli-Libya. Materials and methods: Included in the study 155 MSSA and 144 MRSA ...

  11. High Rate of qacA- and qacB-Positive Methicillin-Resistant Staphylococcus aureus Isolates from Chlorhexidine-Impregnated Catheter-Related Bloodstream Infections

    Ho, Cheng-Mao; Li, Chi-Yuan; Ho, Mao-Wang; Lin, Chien-Yu; Liu, Shu-Hui; Lu, Jang-Jih

    2012-01-01

    Chlorhexidine has been widely used for infection control. Although the use of chlorhexidine-impregnated catheters has reduced catheter-related infections, chlorhexidine-resistant Staphylococcus aureus has emerged. The correlation between the existence of the chlorhexidine-resistant genes qacA and qacB (qacA/B) in methicillin-resistant Staphylococcus aureus (MRSA) isolates and the effectiveness of chlorhexidine-impregnated catheters in the prevention of MRSA infections is unknown. Sixty methic...

  12. Presentación atípica de piomiositis tropical difusa de psoas por Staphylococcus aureus meticilino resistente Atypical presentation of diffuse tropical pyomiositis of the psoas due to methicillin resistant Staphylococcus aureus

    Ray Ticse

    2012-03-01

    Full Text Available La piomiositis tropical difusa primaria es una enfermedad de presentación infrecuente en nuestro medio, con pocos casos asociados a Staphylococcus aureus meticilino resistente, adquirido en la comunidad (MRSA-AC. Se presenta el caso de un paciente de 70 años, con tratamiento irregular para diabetes mellitus tipo 2, que fue hospitalizado por presentar un cuadro de diez días de evolución, con dolor lumbar irradiado a miembro inferior izquierdo, fiebre y flexión forzada de la cadera derecha por dolor a la movilización. El diagnóstico de piomiositis difusa de ambos psoas se realizó con resonancia magnética. Del cultivo de una colección paravertebral posterior se aisló Staphylococcus aureus resistente a oxacilina, penicilina y dicloxacilina.Diffuse tropical primary pyomyositis is an infrequent entity in our country, with few cases associated to communityacquired Methicillin- resistant Staphylococcus aureus. There are no reported cases of Community-Acquired Methicillin- Resistant Staphylococcus aureus (CA- MRSA in Peru. We present the case of a 70 year old male with a previous diagnosis of type 2 diabetes mellitus, receiving irregular treatment, who was admitted to the hospital with a history of 10 days of low back pain radiating to the left leg, fever and forced flexion of the right hip due to pain during movement. The diagnosis of diffuse pyomyositis of both psoas muscles was performed with MRI and culture of a posterior paravertebral collection, from which Staphylococcus aureus resistant to oxacillin, penicillin and dicloxacillin was isolated.

  13. Shedding of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus from adult and pediatric bathers in marine waters

    Sinigalliano Christopher D

    2011-01-01

    Full Text Available Abstract Background Staphylococcus aureus including methicillin resistant S. aureus, MRSA, are human colonizing bacteria that commonly cause opportunistic infections primarily involving the skin in otherwise healthy individuals. These infections have been linked to close contact and sharing of common facilities such as locker rooms, schools and prisons Waterborne exposure and transmission routes have not been traditionally associated with S. aureus infections. Coastal marine waters and beaches used for recreation are potential locations for the combination of high numbers of people with close contact and therefore could contribute to the exposure to and infection by these organisms. The primary aim of this study was to evaluate the amount and characteristics of the shedding of methicillin sensitive S. aureus, MSSA and MRSA by human bathers in marine waters. Results Nasal cultures were collected from bathers, and water samples were collected from two sets of pools designed to isolate and quantify MSSA and MRSA shed by adults and toddlers during exposure to marine water. A combination of selective growth media and biochemical and polymerase chain reaction analysis was used to identify and perform limited characterization of the S. aureus isolated from the water and the participants. Twelve of 15 MRSA isolates collected from the water had identical genetic characteristics as the organisms isolated from the participants exposed to that water while the remaining 3 MRSA were without matching nasal isolates from participants. The amount of S. aureus shed per person corresponded to 105 to 106 CFU per person per 15-minute bathing period, with 15 to 20% of this quantity testing positive for MRSA. Conclusions This is the first report of a comparison of human colonizing organisms with bacteria from human exposed marine water attempting to confirm that participants shed their own colonizing MSSA and MRSA into their bathing milieu. These findings clearly

  14. Methicillin-resistant Staphylococcus aureus (MRSA): identification and susceptibility testing techniques.

    Reygaert, Wanda

    2009-01-01

    Many traditional techniques are useful for identification of MRSA strains, including techniques for detection of penicillin-resistance, such as the nitrocefin disk. Techniques for assessing methicillin-resistance vary from growth on special media or at a lower temperature, to detection of the mecA gene by manual (latex agglutination) and automated (PCR) methods. Technique development is now geared toward making MRSA identification more rapid. Real-time PCR has sped MRSA detection, but can be costly. Resistance to other drugs is also an issue. Clindamycin resistance may need to be induced, so a special disk diffusion test can be performed. Vancomycin resistance is becoming an issue, so alternative drugs need to be identified. Drugs that are currently available for MRSA infections include: daptomycin, linezolid, quinupristin/dalfopristin, and tigecycline. Drugs that are in the development phase include: ceftobiprole, dalbavancin, oritavancin, and telavancin. These drugs provide a promising arsenal against MRSA. PMID:19534447

  15. Postoperative infection of an abdominal mesh due to methicillin resistant Staphylococcus Aureus - A case report

    Ashok R

    2004-01-01

    Full Text Available Methicillin resistant Stephylococcus aureus (MRSA infection has now become a major problem in hospitals. We present a case of postoperative infection MRSA where the primary source of the infection was found to be an abdominal mesh that was used to reinforce the abdominal wall. After one year of surgery, the patient developed wound dehiscence and discharge. MRSA was isolated from the wound, mesh, external nares, throat and axilla. Initially she was started on clindamycin and discharged from the hospital. After 5 months, patient came back to the hospital with infection at the same site. The patient was then treated with vancomycin and MRSA clearance. She responded to the treatment with complete healing of the wound and clearance of MRSA.

  16. Diversity of antimicrobial resistance and virulence genes in methicillin-resistant non-Staphylococcus aureus staphylococci from veal calves.

    Argudín, M Angeles; Vanderhaeghen, Wannes; Butaye, Patrick

    2015-04-01

    In this study we determined whether methicillin-resistant non-Staphylococcus aureus (MRNAS) from veal calves may be a potential reservoir of antimicrobial-resistance and virulence genes. Fifty-eight MRNAS were studied by means of DNA-microarray and PCR for detection of antimicrobial resistance and virulence genes. The isolates carried a variety of antimicrobial-resistance genes [aacA-aphD, aadD, aph3, aadE, sat, spc, ampA, erm(A), erm(B), erm(C), erm(F), erm(T), lnu(A), msr(A)-msr(B), vga(A), mph(C), tet(K), tet(M), tet(L), cat, fexA, dfrA, dfrD, dfrG, dfrK, cfr, fusB, fosB, qacA, qacC, merA-merB]. Some isolates carried resistance genes without showing the corresponding resistance phenotype. Most MRNAS carried typical S. aureus virulence factors like proteases (sspP) and enterotoxins (seg) genes. Most Staphylococcus epidermidis isolates carried the arginine catabolic element, and nearly 40% of the Staphylococcus sciuri isolates carried leukocidins, and/or fibronectin-binding protein genes. MRNAS were highly multi-resistant and represent an important reservoir of antimicrobial resistance and virulence genes. PMID:25637268

  17. In-vitro and In-vivo Evaluation of Silymarin Nanoliposomes against Isolated Methicillin-resistant Staphylococcus aureus.

    Faezizadeh, Zohreh; Gharib, Amir; Godarzee, Masoud

    2015-01-01

    Staphylococcus aureus is an opportunistic pathogen and remains a common cause of burn wound infections. Different studies have shown that entrapment of plant-derived compounds into liposomes could increase their anti-Staphylococcus aureus activity. Silymarin is the bioactive extract from the known plant Silybum marianum L. The objective of this study was to evaluate efficacy of silymarin in free and nanoliposomal forms against isolated methicillin-resistant Staphylococcus aureus (MRSA) strain. Silymarin-loaded nanoliposomes were prepared by extrusion method. The minimum inhibitory concentrations (MICs) of silymarin in free and nanoliposomal forms against MRSA were determined by broth dilution method. The killing rate of free and nanoliposomal forms of silymarin were analyzed. Ultimately, in-vivo therapeutic efficacy of nanoliposomes in burned mice infected by isolated MRSA was examined. The MICs of free and nanoliposomal forms of silymarin against isolated strain were 500 and 125 mg/L, respectively. The killing rate of silymarin-loaded nanoliposomes was higher than those of free silymarin. Topically treatment by silymarin in free and nanoliposomal forms resulted in almost 20 and 100% survival rates, respectively. The results suggest that silymarin-loaded nanoliposomes may provide a basis for future treatment of MRSA infections. PMID:25901172

  18. Rapid detection of methicillin-resistant Staphylococcus aureus directly from clinical samples: methods, effectiveness and cost considerations

    Stürenburg, Enno

    2009-07-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA isolates is a serious public health problem whose ever-increasing rate is commensurate with the pressure it is exerting on the healthcare system. At present, more than 20% of clinical S. aureus isolates in German hospitals are methicillin resistant. Strategies from low-prevalence countries show that this development is not necessarily inevitable. In the Scandinavian countries and the Netherlands, thanks to a rigorous prevention programme, MRSA prevalence has been kept at an acceptably low level (<1–3%. Central to these ‘search and destroy’ control strategies is an admission screening using several MRSA swabs taken from mucocutaneous colonisation sites of high-risk patients (‘MRSA surveillance’. It has also been reported that the speed with which MRSA carriage is detected has an important role to play, as it is a key component of any effective strategy to prevent the pathogen from spreading. Since MRSA culturing involves a 2–3 day delay before the final results are available, rapid detection techniques (commonly referred to as ‘MRSA rapid tests’ using PCR methods and, most recently, rapid culturing methods have been developed. The implementation of rapid tests reduces the time of detection of MRSA carriers from 48–72 to 2–5 h. Clinical evaluation data have shown that MRSA can thus be detected with very high sensitivity. Specificity however is sometimes impaired due to false-positive PCR signals occurring in mixed flora specimens. In order to rule out any false-positive PCR results, a culture screen must always be carried out simultaneously.The data provide preliminary evidence that a PCR assay can reduce nosocomial MRSA transmission in high-risk patients or high-risk areas, whereas an approach that screens all patients admitted to the hospital is probably not effective. Information concerning the cost-effectiveness of rapid MRSA tests is still sparse and thus the issue remains

  19. Zinc oxide therapy increases prevalence and persistence of methicillin-resistant Staphylococcus aureus in pigs: a randomized controlled trial.

    Slifierz, M J; Friendship, R; Weese, J S

    2015-06-01

    There is concern that therapeutic use of zinc oxide (ZnO) in swine production may select for methicillin-resistant Staphylococcus aureus (MRSA) due to co-location of the zinc resistance gene (czrC) and methicillin resistance gene (mecA) within the staphylococcal cassette chromosome mec (SCCmec). The objective of this investigation was to determine whether MRSA carriage in pigs is influenced by exposure to therapeutic doses of in-feed ZnO (3000 mg/kg) when compared to the recommended dietary levels (100 mg/kg). A randomized controlled trial was completed using 110 pigs that were naturally colonized with czrC-positive MRSA. The pigs were followed from birth to weaning (21 d), at which point they were randomized into 8 pens and exposed to either a control feed (100 mg ZnO/kg feed; n = 49 pigs) or a treatment feed (3000 mg ZnO/kg feed; n = 50 pigs); neither feed contained additional antimicrobials. MRSA carriage was monitored weekly in each group for 4 weeks post-weaning. The prevalence of MRSA was significantly higher in the treatment group at 1-week (OR = 18.1; P post-weaning when compared to the control group, but there was no difference later in the nursery phase. Persistent MRSA carriage (testing positive ≥2 times post-weaning) was observed in 2% (1/49) of control pigs and 22% (11/50) of treated pigs (P zinc. These findings demonstrate that the prevalence and persistence of MRSA in nursery pigs can be affected by high levels of in-feed ZnO in the absence of antibiotics. PMID:25209545

  20. Molecular study on methicillin-resistant Staphylococcus aureus strains isolated from dogs and associated personnel in Jordan

    Yaser; Hamadeh; Tarazi; Ahmed; Mahmoud; Almajali; Mustafa; Mohammad; Kheer; Ababneh; Humam; Shawket; Ahmed; Adnan; Saleem; Jaran

    2015-01-01

    Objective: To determine the prevalence, genetic relatedness, and pattern of antimicrobial susceptibility in methicillin-resistant Staphylococcus aureus(S. aureus)(MRSA) isolated from household dogs, farm dogs, and stray dogs, compared to isolates from their associated personnel.Methods: MRSA was isolated from 250 nasal swabs(150 swabs from dogs and 100 swabs from humans). PCR assays were used to detect the presence of both the nuc and mec A genes,which con firmed the identity of S. aureus isolates and the presence of methicillin resistance,respectively. Disk diffusion was used to determine the antibiotic susceptibility against 15 antimicrobial agents along with an E-test that determined the minimum inhibitory concentration for oxacillin. Pulsed field gel electrophoresis was conducted to determine the genetic relatedness of MRSA isolates from dogs to those from associated and unassociated personnel.Results: The prevalence of S. aureus in dogs and humans was 12.7% and 10.0%respectively, while the prevalence of MRSA isolates in dogs and humans was 5.3% and5.0%, respectively. The prevalence of MRSA isolates in household dogs, farm dogs, and stray dogs was 7.8%, 4.7%, and 0.0%, respectively. MRSA isolates demonstrated a significantly higher rate of multi-resistance against three or more antimicrobial agents than methicillin-susceptible S. aureus(MSSA). Trimethoprim-sulphamethoxazole and chloramphenicol were the most effective antibiotics against all MRSA isolates. Pulsed field gel electrophoresis revealed a strong association between dog MRSA isolates and MRSA isolates from strongly associated personnel.Conclusions: MRSA is prevalent in house dogs, as well as in dog rearing centers and among their strongly associated personnel. A strong association was found between the MRSA isolates from dogs and those from humans who are in close contact. In addition,MRSA isolates showed a high rate of multi-resistance compared to MSSA isolates.

  1. Molecular study on methicillin-resistant Staphylococcus aureus strains isolated from dogs and associated personnel in Jordan

    Yaser Hamadeh Tarazi; Ahmed Mahmoud Almajali; Mustafa Mohammad Kheer Ababneh; Humam Shawket Ahmed; Adnan Saleem Jaran

    2015-01-01

    Objective:To determine the prevalence, genetic relatedness, and pattern of antimicrobial susceptibility in methicillin-resistant Staphylococcus aureus (S. aureus) (MRSA) isolated from household dogs, farm dogs, and stray dogs, compared to isolates from their associated personnel. Methods: MRSA was isolated from 250 nasal swabs (150 swabs from dogs and 100 swabs from humans). PCR assays were used to detect the presence of both the nuc and mecA genes, which confirmed the identity of S. aureus isolates and the presence of methicillin resistance, respectively. Disk diffusion was used to determine the antibiotic susceptibility against 15 antimicrobial agents along with an E-test that determined the minimum inhibitory concentration for oxacillin. Pulsed field gel electrophoresis was conducted to determine the genetic relatedness of MRSA isolates from dogs to those from associated and unassociated personnel. Results:The prevalence of S. aureus in dogs and humans was 12.7%and 10.0%respectively, while the prevalence of MRSA isolates in dogs and humans was 5.3%and 5.0%, respectively. The prevalence of MRSA isolates in household dogs, farm dogs, and stray dogs was 7.8%, 4.7%, and 0.0%, respectively. MRSA isolates demonstrated a significantly higher rate of multi-resistance against three or more antimicrobial agents than methicillin-susceptible S. aureus (MSSA). Trimethoprim-sulphamethoxazole and chloramphenicol were the most effective antibiotics against all MRSA isolates. Pulsed field gel electrophoresis revealed a strong association between dog MRSA isolates and MRSA isolates from strongly associated personnel. Conclusions:MRSA is prevalent in house dogs, as well as in dog rearing centers and among their strongly associated personnel. A strong association was found between the MRSA isolates from dogs and those from humans who are in close contact. In addition, MRSA isolates showed a high rate of multi-resistance compared to MSSA isolates.

  2. COMPARISON OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS IN HEALTHY COMMUNITY HOSPITAL VISITORS[CA-MRSA] AND HOSPITAL STAFF [HA-MRSA

    Nirmal A Pathare

    2015-10-01

    Full Text Available Background: The prevalence of community associated methicillin resistant Staphylococcus aureus [CA-MRSA] in unknown in Oman. Methods: Nasal and cell phones swabs were collected from hospital visitors and health-care workers on sterile polyester swabs and directly inoculated onto a mannitol salt agar containing oxacillin, allowing growth of methicillin-resistant microorganisms. Antibiotic susceptibility tests were performed using Kirby Bauer’s disc diffusion method on the isolates. A brief survey questionnaire was requested be filled to ascertain the exposure to known risk factors for CA-MRSA carriage. Results: Overall, nasal colonization with CA-MRSA was seen in 34 individuals (18%, 95% confidence interval [CI] =12.5%-23.5%, whereas, CA-MRSA was additionally isolated from the cell phone surface in 12 participants (6.3%, 95% CI =5.6%-6.98%. Nasal colonization prevalence with HA-MRSA was seen in 16 individuals (13.8%, 95% confidence interval [CI] =7.5%-20.06%, whereas, HA-MRSA was additionally isolated from the cell phone surface in 3 participants (2.6%, 95% CI =1.7-4.54.  Antibiotic sensitivity was 100% to linezolid and rifampicin in the CA-MRSA isolates. Antibiotic resistance to vancomycin and clindamycin varied between 9-11 % in the CA-MRSA isolates.  There was no statistically significant correlation between CA-MRSA nasal carriage and the risk factors (P>0.05, Chi-square test. Conclusions: The prevalence of CA-MRSA in the healthy community hospital visitors was 18 % (95% CI, 12.5% to 23.5% as compared to 13.8% [HA-MRSA] in the hospital health-care staff. In spite of a significant prevalence of CA-MRSA, these strains were mostly sensitive. Recommendation the universal techniques of hand washing, personal hygiene and sanitation are thus warranted.

  3. Eradication of methicillin-resistant Staphylococcus aureus and of Enterobacteriaceae expressing extended-spectrum beta-lactamases on a model pig farm.

    Schmithausen, Ricarda Maria; Kellner, Sophia Ricarda; Schulze-Geisthoevel, Sophia Veronika; Hack, Sylvia; Engelhart, Steffen; Bodenstein, Isabel; Al-Sabti, Nahed; Reif, Marion; Fimmers, Rolf; Körber-Irrgang, Barbara; Harlizius, Jürgen; Hoerauf, Achim; Exner, Martin; Bierbaum, Gabriele; Petersen, Brigitte; Bekeredjian-Ding, Isabelle

    2015-11-01

    Colonization of livestock with bacteria resistant to antibiotics is considered a risk for the entry of drug-resistant pathogens into the food chain. For this reason, there is a need for novel concepts to address the eradication of drug-resistant commensals on farms. In the present report, we evaluated the decontamination measures taken on a farm contaminated with methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae expressing extended-spectrum β-lactamases (ESBL-E). The decontamination process preceded the conversion from piglet breeding to gilt production. Microbiological surveillance showed that the decontamination measures eliminated the MRSA and ESBL-E strains that were detected on the farm before the complete removal of pigs, cleaning and disinfection of the stable, and construction of an additional stable meeting high-quality standards. After pig production was restarted, ESBL-E remained undetectable over 12 months, but MRSA was recovered from pigs and the environment within the first 2 days. However, spa (Staphylococcus aureus protein A gene) typing revealed acquisition of an MRSA strain (type t034) that had not been detected before decontamination. Interestingly, we observed that a farmworker who had been colonized with the prior MRSA strain (t2011) acquired the new strain (t034) after 2 months. In summary, this report demonstrates that decontamination protocols similar to those used here can lead to successful elimination of contaminating MRSA and ESBL-E in pigs and the stable environment. Nevertheless, decontamination protocols do not prevent the acquisition of new MRSA strains. PMID:26341200

  4. 一起缅甸输入霍乱疫情的调查处置%Progress in research of nosocomial infection of methicillin-resistant Staphylococcus aureus

    李琼芬; 余建兴; 杨建斌

    2012-01-01

    2010年12月14日,云南省德宏州中缅边境的潞西市轩岗乡户弄村发生1起缅甸输入O1群稻叶型霍乱疫情,患者经云南省德宏州人民医院规范治疗7d,症状消失,两次采样,实验室检测结果为阴性,痊愈出院,病例未出现重症及死亡.%The wide use of antibiotics and development of new broad-spectrum antibiotics have resulted in serious drug resistance of bacteria, which is one of the important public health problems in the globe. Nosocomial infection of methicillin-resistant Staphylococcus aureus (MRSA) is common and duo to its multi drug resistance and proneness to spread f the treatment of MRSA infection is difficult. Not only the nosocomial infection of MRSA infection is seriuos, but also the community acquired infection of MRSA is in increase. Vancomycin-resistant Staphylococcus aureus (VRSA) has emerged in foreign countries, which is called super-bacteria (Superbug) or silent killer- This paper summerizes the progress in the research of the nosocomial infection of MRSA and in the prevetnion and treatment of MRSA infection.

  5. A Double-Blind, Randomized, Controlled Trial of Topical Polysporin Triple Compound Versus Topical Mupirocin for the Eradication of Colonization with Methicillin-Resistant Staphylococcus aureus in a Complex Continuing Care Population

    S O’Grady

    2009-01-01

    Full Text Available BACKGROUND: Intranasal mupirocin or Polysporin Triple (PT ointment (polymyxin B, bacitracin, gramicidin, in combination with chlorhexidine body washes, have been used for eradicating methicillin-resistant Staphylococcus aureus (MRSA, but no comparative studies have been done.

  6. Potentiating activity of luteolin on membrane permeabilizing agent and ATPase inhibitor against methicillin-resistant Staphylococcus aureus

    Dae-Ki Joung; Dong-Won Shin; Dong-Yeul Kwon; Young-Seob Lee; Sin-Hee Han; Sang-Won Lee; Seon-Woo Cha; Su-Hyun Mun; Ryong Kong; Ok-Hwa Kang; Ho-Jun Song

    2016-01-01

    Objective: To investigate the mechanism of antibacterial activity of luteolin (LUT) against methicillin-resistant Staphylococcus aureus (MRSA). Methods: The mechanism of anti-MRSA activity of LUT was analyzed by the viability assay in membrane permeabilizing agent, ATPase inhibitors, and peptidoglycan (PGN) derived from Staphylococcus aureus (S. aureus). Also, transmission electron microscopy was used to monitor survival characteristics and changes in S. aureus morphology. Results: Compared to the LUT alone, the optical density of suspensions treated with the combination of 125 μg/mL Tris and 250 μg/mL DCCD were reduced to 60%and 46%, respectively. PGN (15.6 μg/mL) gradually impeded the activity of LUT, and PGN (62.5 μg/mL) completely blocked the activity of LUT on S. aureus. Conclusions: Increased susceptibility to LUT with the Tris and DCCD combinations is evident in all tested MRSA isolates. The results indicate LUT synergy in increasing cytoplasmic membrane permeability and inhibiting ATPase. S. aureus PGN directly blocks the antibacterial activity of LUT, suggesting the direct binding of LUT with PGN. These findings may be validated for the development of antibacterial agent for low MRSA resistance.

  7. Occupational determinants of methicillin-resistant Staphylococcus aureus colonization among healthcare workers: a longitudinal study in a rehabilitation center.

    Legrand, J; Temime, L; Lawrence, C; Herrmann, J L; Boelle, P Y; Guillemot, D

    2015-07-01

    BACKGROUND Staphylococcus aureus carriage among healthcare workers (HCWs) is a concern in hospital settings, where it may provide a reservoir for later infections in both patients and staff. Earlier studies have shown that the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage in HCWs is highly variable, depending notably on location, hospital department type, MRSA prevalence among patients, and type of contacts with patients. However, MRSA incidence in HCWs and its occupational determinants have seldom been studied. METHODS A prospective, observational cohort study was conducted between May and October 2009 in a French rehabilitation center hospital. HCWs and patients were screened weekly for S. aureus nasal carriage. Methicillin-susceptible S. aureus and MRSA prevalence and incidence were estimated and factors associated with MRSA acquisition were identified using generalized estimating equation regression methods. RESULTS Among 343 HCWs included in the analysis, the average prevalence was 27% (95% CI, 24%-29%) for methicillin-susceptible S. aureus and 10% (8%-11%) for MRSA. We observed 129 MRSA colonization events. According to the multivariable analysis, high MRSA prevalence level among patients and HCW occupation were significantly associated with MRSA acquisition in HCWs, with assistant nurses being more at risk than nurses (odds ratio, 2.2; 95% CI, 1.4-3.6). CONCLUSIONS Our findings may help further our understanding of the transmission dynamics of MRSA carriage acquisition in HCWs, suggesting that it is notably driven by carriage among patients and by the type of contact with patients. PMID:25785501

  8. Modified PAP method to detect heteroresistance to vancomycin among methicillin resistant Staphylococcus aureus isolates at a tertiary care hospital

    Iyer R

    2008-01-01

    Full Text Available This study was an attempt at developing, establishing, validating and comparing the modified PAP method for detection of hetero-vancomycin resistant Staphylococcus aureus (h-VRSA with the routine antimicrobial susceptibility testing (using the BSAC standardized disc diffusion method, minimum inhibitory concentrations of vancomycin using standard E-test methodology and the Hiramatsu′s screening method. A total of 50 methicillin resistant Staphylococcus aureus obtained from various clinical specimens, along with the Mu 3 and Mu 50 strains as controls, were studied. No VRSA isolates were obtained. However, four of the test strains were positive by the Hiramatsu′s screening method, of which only one isolate could be confirmed by the modified PAP analysis method. This isolate was a coloniser from the drain fluid of a liver transplant recipient. The sensitivity, specificity, positive predictive value and the overall efficiency of the Hiramatsu′s screening method with the modified PAP analysis as the gold standard were found to be 100, 93.8, 25 and 94%, respectively. It is very essential for clinical laboratories to screen for h-VRSA, given the increasing use of glycopeptide antibiotics in therapy and the potential for failed therapy in patients infected with these strains.

  9. Methicillin-resistant Staphylococcus aureus colonization and disease severity in atopic dermatitis: A cross-sectional study from South India

    Soumya Jagadeesan

    2014-01-01

    Full Text Available Background: Colonization by methicillin-resistant Staphylococcus aureus (MRSA in atopic dermatitis is little studied but has therapeutic implications. It may have a role in disease severity given the additional virulence factors associated. Aims: Our aims were to record the proportion of patients with MRSA colonization in atopic dermatitis and to ascertain if any association exists between MRSA colonization and disease severity. Methods: An observational cross-sectional study involving children aged≤12 years with atopic dermatitis attending the outpatient department of Government Medical College, Kottayam was conducted. Socio-demographic data, exacerbating factors and risk factors for hospital care-associated MRSA were documented. Extent of atopic dermatitis was recorded using a standardized scale (Eczema Area Severity Index, EASI. Skin swabs were taken from anterior nares and the worst affected atopic dermatitis sites for culture and sensitivity. Results: Of the 119 subjects recruited during the study period (November 2009-April 2011, Staphylococcus aureus was isolated from 110 (92.4% patients and MRSA from 30 (25.21% patients. A total of 18 patients with MRSA had risk factors for healthcare associated-MRSA. The patients whose cultures grew MRSA were found to have significantly higher EASI score when compared to those patients colonized with methicillin sensitive Staphylococcus aureus (P < 0.01. Presence of Staphylococcus aureus, early age of onset, presence of food allergies, seasonal exacerbation and inadequate breastfeeding did not seem to influence disease severity. Conclusions: There is a high degree of prevalence of MRSA (25.2% in atopic dermatitis and presence of MRSA is associated with increased disease severity. Further studies are needed to validate these findings.

  10. Clinical course and management of postoperative methicillin-resistant Staphylococcus aureus keratitis in immunocompromised patients: two case reports

    Prabhu SP

    2011-12-01

    Full Text Available Timothy Y Chou1, Sujata P Prabhu21Department of Ophthalmology, State University of New York Stony Brook, Stony Brook, NY, 2Shiley Eye Center, University of California San Diego, La Jolla, CA, USAAbstract: We describe the clinical course and successful treatment of two cases of methicillin-resistant Staphylococcus aureus (MRSA keratitis. In case 1, MRSA keratitis occurred 5 days after cataract extraction, associated with endophthalmitis; in case 2, diagnosis was made 19 months after penetrating keratoplasty. Treatment in both cases consisted of topical fortified vancomycin and fortified bacitracin. A third topical antibiotic, polymyxin B-trimethoprim, was added to the therapeutic regimen in case 2, one month into the treatment. Oral doxycycline was prescribed to reduce collagenase activity and treat blepharitis. Mupirocin nasal ointment and skin antiseptics were used to decrease and eliminate potential MRSA colonization. Topical prednisolone acetate 1% was applied conservatively to mitigate inflammation in both cases. In case 2, topical cyclosporine A was also used for similar purposes. Keratitis may have worsened while on these immune-modulating drops, especially in case 2, and eradication of infection may have been slowed. Eventually both patients achieved full resolution of infection. Duration of keratitis was 3 and 1.5 months, respectively. Polyantimicrobial therapy is effective in eradicating MRSA-related postoperative keratitis. Topical fortified vancomycin and fortified bacitracin were used in both cases, with a third topical antibiotic, polymyxin B-trimethoprim, also required in case 2. Oral doxycycline, nasal mupirocin, and antiseptic soap may be useful adjuncts in management. Treatment time to achieve full resolution may be prolonged relative to other types of bacterial keratitis. Alterations in immune status may have lengthened the time of treatment. Our two patients were immune compromised and were also susceptible to endophthalmitis

  11. Induction of systemic and mucosal immunity against methicillin-resistant Staphylococcus aureus infection by a novel nanoemulsion adjuvant vaccine

    Sun HW

    2015-12-01

    Full Text Available HongWu Sun,1,* Chao Wei,1,* BaoShuai Liu,1 HaiMing Jing,1 Qiang Feng,2 YaNan Tong,1 Yun Yang,1 LiuYang Yang,1 QianFei Zuo,1 Yi Zhang,1 QuanMing Zou,1 Hao Zeng1 1National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University of Chinese PLA, 2Department of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, People’s Republic of China *These authors contributed equally to this work Abstract: The Gram-positive bacterial pathogen methicillin-resistant Staphylococcus aureus (MRSA can cause infections in the bloodstream, endocardial tissue, respiratory tract, culture-confirmed skin, or soft tissue. There are currently no effective vaccines, and none are expected to become available in the near future. An effective vaccine capable of eliciting both systemic and mucosal immune responses is also urgently needed. Here, we reported a novel oil-in-water nanoemulsion adjuvant vaccine containing an MRSA recombination protein antigen, Cremophor EL-35® as a surfactant, and propylene glycol as a co-surfactant. This nanoemulsion vaccine, whose average diameter was 31.34±0.49 nm, demonstrated good protein structure integrity, protein specificity, and good stability at room temperature for 1 year. The intramuscular systemic and nasal mucosal immune responses demonstrated that this nanoemulsion vaccine could improve the specific immune responses of immunoglobulin (IgG and related subclasses, such as IgG1, IgG2a, and IgG2b, as well as IgA, in the serum after Balb/c mice intramuscular immunization and C57 mice nasal immunization. Furthermore, this nanoemulsion vaccine also markedly enhanced the interferon-γ and interleukin-17A cytokine cell immune response, improved the survival ratio, and reduced bacterial colonization. Taken together, our results show that this novel nanoemulsion vaccine has great potential and is a

  12. Presence, Distribution, and Molecular Epidemiology of Methicillin-Resistant Staphylococcus aureus in a Small Animal Teaching Hospital: A Year-Long Active Surveillance Targeting Dogs and Their Environment

    van Balen, Joany; Kelley, Christina; Nava-Hoet, Rocio C; Bateman, Shane; Hillier, Andrew; Dyce, Jonathan; Wittum, Thomas E.; Hoet, Armando E

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is known to be present in small animal veterinary clinical environments. However, a better understanding of the ecology and dynamics of MRSA in these environments is necessary for the development of effective infectious disease prevention and control programs. To achieve this goal, a yearlong active MRSA surveillance program was established at The Ohio State University (OSU) Veterinary Medical Center to describe the spatial and molecular epid...

  13. Cell wall monoglycine cross-bridges and methicillin hypersusceptibility in a femAB null mutant of methicillin-resistant Staphylococcus aureus.

    Strandén, A M; Ehlert, K; Labischinski, H.; Berger-Bächi, B.

    1997-01-01

    The femAB operon is involved in the formation of the characteristic pentaglycine side chain of the staphylococcal peptidoglycan. Allele replacement of the femAB operon with the tetracycline resistance determinant tetK in a methicillin-resistant Staphylococcus aureus strain resulted in impaired growth, methicillin hypersusceptibility, and lysostaphin resistance. The usual pentaglycine cross-bridges were replaced by monoglycine bridges exclusively, and cross-linking of the peptidoglycan strands...

  14. Co-Therapy Using Lytic Bacteriophage and Linezolid: Effective Treatment in Eliminating Methicillin Resistant Staphylococcus aureus (MRSA) from Diabetic Foot Infections

    Chhibber, Sanjay; Kaur, Tarsem; Sandeep Kaur

    2013-01-01

    Background Staphylococcus aureus remains the predominant pathogen in diabetic foot infections and prevalence of methicillin resistant S.aureus (MRSA) strains further complicates the situation. The incidence of MRSA in infected foot ulcers is 15–30% and there is an alarming trend for its increase in many countries. Diabetes acts as an immunosuppressive state decreasing the overall immune functioning of body and to worsen the situation, wounds inflicted with drug resistant strains represent a m...

  15. Persistence of Livestock-Associated Methicillin-Resistant Staphylococcus aureus in Field Workers after Short-Term Occupational Exposure to Pigs and Veal Calves

    Cleef, van, B.A.G.L.; Graveland, H.; Haenen, A.P.J.; van de Giessen, A. W.; Heederik, D.; Wagenaar, J. A.; Kluijtmans, J.A.J.W.

    2011-01-01

    The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage in pig and veal calf farmers in the Netherlands is estimated at 25 to 35%. However, no information is available about MRSA carriage in humans after short-term occupational exposure to pigs or veal calves. This study examines the prevalence and duration of MRSA acquisition after short-term intensive exposure to pigs or veal calves for persons not exposed to livestock on a daily basis. The study was performed with fie...

  16. Characterization of Resistance to Aminoglycosides in Methicillin-Resistant Staphylococcus aureus Strains Isolated From a Tertiary Care Hospital in Tehran, Iran

    Rahimi, Fateh

    2016-01-01

    Background: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common nosocomial pathogens which can cause a broad spectrum of infections. Objectives: The current study aimed to describe the frequency and antibiotic susceptibility patterns of clonal groups of gentamicin-resistant strains of MRSA isolated from a tertiary care hospital in Tehran, Iran. Materials and Methods: A total of 301 S. aureus isolates were collected during January to November 2012. All of the isolates ...

  17. Cloning and Occurrence of czrC, a Gene Conferring Cadmium and Zinc Resistance in Methicillin-Resistant Staphylococcus aureus CC398 Isolates

    Cavaco, L.M.; Hasman, H.; Stegger, M.; Andersen, P S; Skov, R.; Fluit, A. C.; Ito, T.; Aarestrup, F. M.

    2010-01-01

    We recently reported a phenotypic association between reduced susceptibility to zinc and methicillin resistance in Staphylococcus aureus CC398 isolates from Danish swine (F. M. Aarestrup, L. M. Cavaco, and H. Hasman, Vet. Microbiol. 142:455-457, 2009). The aim of this study was to identify the genetic determinant causing zinc resistance in CC398 and examine its prevalence in isolates of animal and human origin. Based on the sequence of the staphylococcal cassette chromosome mec (SCCmec) eleme...

  18. An economic model to compare linezolid and vancomycin for the treatment of confirmed methicillin-resistant Staphylococcus aureus nosocomial pneumonia in Germany

    Stephens, Jennifer

    2014-01-01

    Dipen A Patel,1 Andre Michel,2 Jennifer Stephens,1 Bertram Weber,3 Christian Petrik,4 Claudie Charbonneau5 1Health Economic and Outcomes Research, Pharmerit International, Bethesda, MD, USA; 2Klinikum Hanau GmbH, Hanau, Germany; 3Health Technology Assessment and Outcomes Research, 4Anti-infectives, Pfizer, Berlin, Germany; 5Pfizer International Operations, Pfizer France, Paris, France Background: Across Europe, methicillin-resistant Staphylococcus aureus (MRSA) is considered to be the primar...

  19. Staphylococcal Cassette Chromosome mec (SCCmec) Typing of Methicillin-Resistant Staphylococcus aureus Strains Isolated in 11 Asian Countries: a Proposal for a New Nomenclature for SCCmec Elements

    Chongtrakool, Piriyaporn; Ito, Teruyo; Ma, Xiao Xue; Kondo, Yoko; Trakulsomboon, Suwanna; Tiensasitorn, Chuntima; Jamklang, Mantana; Chavalit, Tavinun; Song, Jae-Hoon; Hiramatsu, Keiichi

    2006-01-01

    A description of staphylococcal cassette chromosome mec (SCCmec) elements carried by 615 methicillin-resistant Staphylococcus aureus (MRSA) strains isolated in 11 Asian countries is reported, and a novel nomenclatural system based on their structures is proposed. The 615 strains were classified as type 3A (370 strains), type 2A (207 strains), type 2B (32 strains), type 1B (1 strain), and nontypeable (5 strains). The previously reported type III SCCmec (DDBJ/EMBL/GenBank accession no. AB037671...

  20. Relationship of In Vitro Synergy and Treatment Outcome with Daptomycin plus Rifampin in Patients with Invasive Methicillin-Resistant Staphylococcus aureus Infections

    Rose, Warren E.; Berti, Andrew D.; Hatch, Jacob B.; Maki, Dennis G.

    2013-01-01

    We report the findings of a study examining the relationship between in vitro daptomycin-rifampin synergy and the therapeutic outcome of 12 patients with complex deep methicillin-resistant Staphylococcus aureus (MRSA) infections treated for prolonged periods with this combination. Checkerboard synergy was found in nine cases and was 100% predictive of therapeutic success; absence of synergy was found in three cases, two of which were therapeutic failures (P = 0.045). No relationship was obser...

  1. Comparison of Levofloxacin, Alatrofloxacin, and Vancomycin for Prophylaxis and Treatment of Experimental Foreign-Body-Associated Infection by Methicillin-Resistant Staphylococcus aureus

    Vaudaux, Pierre; Francois, Patrice; Bisognano, Carmelo; Schrenzel, Jacques; Lew, Daniel P.

    2002-01-01

    The prophylactic and therapeutic activities of two fluoroquinolones, levofloxacin and alatrofloxacin (the l-Ala-l-Ala prodrug of trovafloxacin), were compared to those of vancomycin in two different experimental models of foreign-body-associated infections caused by methicillin-resistant but quinolone-susceptible Staphylococcus aureus (MRSA) isolates. In a guinea pig model of prophylaxis, subcutaneously implanted tissue cages were infected with 103 CFU of MRSA, which was a 100% infectious dos...

  2. The effect of rapid screening for methicillin-resistant Staphylococcus aureus (MRSA) on the identification and earlier isolation of MRSA-positive patients.

    Creamer, Eilish

    2010-04-01

    (1) To determine whether rapid screening with polymerase chain reaction (PCR) assays leads to the earlier isolation of patients at risk for methicillin-resistant Staphylococcus aureus (MRSA) colonization, (2) to assess compliance with routine MRSA screening protocols, (3) to confirm the diagnostic accuracy of the Xpert MRSA real-time PCR assay (Cepheid) by comparison with culture, and (4) to compare turnaround times for PCR assay results with those for culture results.

  3. Novel Multiplex PCR Assay for Characterization and Concomitant Subtyping of Staphylococcal Cassette Chromosome mec Types I to V in Methicillin-Resistant Staphylococcus aureus

    Zhang, Kunyan; McClure, Jo-Ann; Elsayed, Sameer; Louie, Thomas; Conly, John M

    2005-01-01

    Staphylococcal cassette chromosome mec (SCCmec) typing is essential for understanding the molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA). SCCmec elements are currently classified into types I to V based on the nature of the mec and ccr gene complexes, and are further classified into subtypes according to their junkyard region DNA segments. Previously described traditional SCCmec PCR typing schemes require multiple primer sets and PCR experiments, while a previous...

  4. SDS-PAGE and gel IEF – tool for differentiation of methicillin-resistant and methicillin-sensitive strains of Staphylococcus aureus

    Tesařová, Marie; Horká, Marie; Moravcová, Dana; Svojanovská, Lenka; Mlynariková, K.; Růžička, F.

    2016-01-01

    Roč. 72, č. 3 (2016), s. 315-320. ISSN 0343-8651 R&D Projects: GA MV VG20112015021 Institutional support: RVO:68081715 Keywords : methicillin-resistant and methicillin-sensitive Staphylococcus aureus * sodium dodecylsulphate polyacrylamide gel electrophoresis * gel isoelectric focusing * precipitated proteins Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.423, year: 2014 http://hdl.handle.net/11104/0251069

  5. Random amplified polymorphic DNA assay is less discriminant than pulsed-field gel electrophoresis for typing strains of methicillin-resistant Staphylococcus aureus.

    Saulnier, P; Bourneix, C; Prévost, G; Andremont, A

    1993-01-01

    Twenty-six strains of methicillin-resistant Staphylococcus aureus with different pulsed-field gel electrophoresis fingerprints were tested by random amplified polymorphic DNA assay with three primers, resulting in 15 to 20 different random amplified polymorphic DNA fingerprints. By summing the results for the three primers, the number of different fingerprints increased to 25, but two strains could not be differentiated. We conclude that pulsed-field gel electrophoresis remains the best metho...

  6. Assessments of Thioridazine as a Helper Compound to Dicloxacillin against Methicillin-Resistant Staphylococcus aureus: In Vivo Trials in a Mouse Peritonitis Model

    Michael Stenger; Kristoffer Hendel; Peter Bollen; Licht, Peter B.; Hans Jørn Kolmos; Klitgaard, Janne K.

    2015-01-01

    Introduction The rise in antimicrobial resistance is a major global concern and requires new treatment strategies. The use of helper compounds, such as thioridazine (TDZ), an antipsychotic drug, in combination with traditional antibiotics must be investigated. Objectives The aim of this study was to investigate the efficacy of TDZ as a helper compound for dicloxacillin (DCX) against methicillin-resistant Staphylococcus aureus (MRSA) in vivo, and compare the combination treatment of DCX+TDZ wi...

  7. 2-D GEL ELECTROPHORESIS MAP OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS TREATED WITH QUERCUS INFECTORIA GALL EXTRACT

    Dayang Fredalina Basri; Lee Seng Aik; Radhiah Khairon; Mariati Abdul Rahman

    2013-01-01

    The widespread outbreak of Methicillin-Resistant Staphylococcus Aureus (MRSA) has caused clinical and epidemiological concern in hospital environment. The emergence of Vancomycin-Intermediate S. Aureus (VISA) and, more recently, Vancomycin-Resistant S. Aureus (VRSA) has further alarmed clinician and scientist worlwide. The objective of this study is to determine the optimum concentration of sample protein from MRSA after treatment with acetone extract from Quercus infectoria gall. Comparison ...

  8. Methicillin-Resistant Staphylococcus aureus in a Canadian Intensive Care Unit: Delays in Initiating Effective Therapy Due to the Low Prevalence of Infection

    Wendy Sligl; Geoffrey Taylor; RT Noel Gibney; Robert Rennie; Linda Chui

    2007-01-01

    INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) infection in intensive care units (ICUs) has increased dramatically in prevalence in recent years, and is associated with increased morbidity, mortality and cost of care. The aim of the present study was to describe the epidemiology and outcomes of MRSA infection in the general systems ICU at the University of Alberta Hospital in Edmonton, Alberta.METHODS: A retrospective cohort analysis of patients infected with MRSA in a gener...

  9. A retrospective analysis of practice patterns in the treatment of methicillin-resistant Staphylococcus aureus skin and soft tissue infections at three Canadian tertiary care centres

    John M Conly; Stiver, H. Grant; Weiss, Karl A.; Becker, Debbie L; Rosner, Andrew J; Miller, Elizabeth

    2003-01-01

    BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) infections are increasingly being encountered and pose an increasing burden to the health care system in Canada.OBJECTIVE: To elucidate and characterize the factors influencing the current MRSA treatment patterns in patients with skin and soft tissue infections (SSTIs) before linezolid became available on the Canadian market.METHODS: A retrospective study collected demographic, treatment and resource use data on patients hospitali...

  10. Cost comparison of linezolid versus vancomycin for treatment of complicated skin and skin-structure infection caused by methicillin-resistant Staphylococcus aureus in Quebec

    Martine Pettigrew; Daniel JG Thirion; Michael Libman; Giovanni Zanotti

    2012-01-01

    BACKGROUND: In Canada, complicated skin and skin-structure infection (cSSSI) caused by methicillin-resistant Staphylococcus aureus (MRSA) is usually treated with antibiotics in hospital, with a follow-up course at home for stable patients. The cost implications of using intravenous and oral linezolid instead of intravenous vancomycin in Canadian clinical practice have not been examined.OBJECTIVES: To evaluate the potential treatment cost impact for the Quebec health care system of linezolid v...

  11. Nasal Carriage of Multi-Drug Resistant Panton-Valentine Leucocidin-Positive Methicillin-Resistant Staphylococcus aureus in Children in Tripoli-Libya

    Al-haddad, Omaima H.; Zorgani, Abdulaziz; Sifaw Ghenghesh, Khalifa

    2014-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) colonized children are at an increased risk of developing infections than methicillin-sensitive S. aureus colonized children. Nasal specimens from inpatient children, mothers of inpatient children, healthcare workers, and outpatient children at Tripoli Children Hospital (TCH) were examined for MRSA by chromogenic MRSA ID medium. Susceptibility of MRSA isolates to antibiotics was determined by the disc diffusion method. The nasal carriage rate...

  12. Comparison of BD GeneOhm Methicillin-Resistant Staphylococcus aureus (MRSA) PCR versus the CHROMagar MRSA Assay for Screening Patients for the Presence of MRSA Strains▿

    Boyce, John M.; Havill, Nancy L.

    2007-01-01

    We compared the BD GeneOhm methicillin-resistant Staphylococcus aureus (MRSA) real-time PCR assay with the CHROMagar MRSA assay for the detection of MRSA in 286 nasal surveillance specimens. Compared with the CHROMagar MRSA assay, PCR had sensitivity, specificity, positive predictive value, and negative predictive values of 100%, 98.6%, 95.8%, and 100%, respectively. The mean PCR turnaround time was 14.5 h.

  13. Epidemiology of Emerging Methicillin-Resistant Staphylococcus aureus (MRSA) in Denmark: a Nationwide Study in a Country with Low Prevalence of MRSA Infection

    Faria, Nuno A.; Oliveira, Duarte C.; Westh, Henrik; Monnet, Dominique L.; Larsen, Anders R.; Skov, Robert; de Lencastre, Hermínia

    2005-01-01

    Strict infection control measures introduced during the 1970s have kept the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections extremely low in Denmark. Nevertheless, similarly to other countries, MRSA infections began to appear in the community in the late 1990s. A nationwide surveillance program has collected and stored all MRSA isolates since 1988 and, since 1999, clinical information has been also recorded. We used this information and isolates in a detailed epidem...

  14. Comparison of Community-Associated and Health Care-Associated Methicillin-Resistant Staphylococcus aureus in Canada: Results from CANWARD 2007

    Nichol, Kimberly A.; McCracken, Melissa; DeCorby, Melanie R.; Thompson, Kristjan; Mulvey, Michael R; Karlowsky, James A.; Hoban, Daryl J.; Zhanel, George G

    2009-01-01

    BACKGROUND: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) differ from health care-associated MRSA (HA-MRSA) in their genotypic and phenotypic characteristics. The purpose of the present study was to compare the demographics, antimicrobial susceptibilities and molecular epidemiology of CA-MRSA and HA-MRSA in Canada. METHODS: In 2007, 385 MRSA isolates were collected from Canadian patients attending hospital clinics, emergency rooms, medical/ surgical wards and inte...

  15. Incidence of methicillin-resistant Staphylococcus aureus infection in a children's hospital in the Washington metropolitan area of the United States, 2003 – 2010

    Song, Xiaoyan; Cogen, Jonathan; Singh, Nalini

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major public health threat. In this retrospective cohort study, we included patients with laboratory-confirmed MRSA infections treated at Children's National Medical Center in Washington, District of Columbia between July 2003 and December 2010. The secular trends in the incidence rates of skin/soft tissue and invasive MRSA infections were assessed. Molecular analyses were performed on a subset of patients with invasive infec...

  16. Nine years′ review on preseptal and orbital cellulitis and emergence of community-acquired methicillin-resistant Staphylococus aureus in a tertiary hospital in India

    Datta G Pandian

    2011-01-01

    Full Text Available Context: Preseptal cellulitis is the commonest orbital disease which frequently needs to be differentiated from orbital cellulitis. Prompt diagnosis and treatment with appropriate antibiotics can prevent vision loss and life-threatening complications of orbital cellulitis. Aims: To describe the clinical profile of cases with preseptal and orbital cellulitis admitted to a tertiary care hospital during a period of nine years. The causative organisms and the clinical outcome were analyzed. Settings and Design : Retrospective descriptive case study done in a tertiary care hospital in South India. Material and Methods: The in-patient records of patients with preseptal and orbital cellulitis were reviewed from 1998 to 2006. The factors reviewed included ocular findings aiding in the distinction of the two clinical conditions, the duration of symptoms, the duration of hospital stay, microbiological culture report of pus or wound swab, blood culture, drugs used for treatment, the response to therapy and complications. Statistical Analysis Used: Descriptive analysis. Results: One hundred and ten cases, 77 patients with preseptal cellulitis and 33 patients with orbital cellulitis were reviewed. Five percent of children and 21% of adults presented with cutaneous anthrax contributing to preseptal cellulitis. Thirty-nine percent cases with orbital cellulitis were caused by methicillin-resistant Staphylococcus aureus (MRSA. Conclusions: This study has helped in identifying organisms which cause orbital infections, especially community-acquired MRSA. It indicates the need for modifying our empirical antimicrobial therapy, especially in orbital cellulitis.

  17. Whole genome analysis of a community-associated methicillin-resistant Staphylococcus aureus ST59 isolate from a case of human sepsis and severe pneumonia in China.

    Tingting Qu

    Full Text Available We report a case of necrotizing pneumonia in a young patient caused by community acquired-methicillin resistant Staphylococcus aureus (CA-MRSA in a teaching hospital in the People's Republic of China. The patient had a typical clinical presentation and was successfully treated with antibiotics and intravenous immunoglobulin. A CA-MRSA strain, named SA268, was isolated from the blood of the patient. The isolate was susceptible to most antimicrobial agents, except cephalosporins, penicillins, and β-lactamase inhibitor combinations. Multi-locus sequence typing (MLST assigned SA268 to ST59, a clone widely spread in eastern Asia. The strain was positive for Panton Valentine Leukocidin (PVL-encoding genes and SCCmec type V. We sequenced the complete genome of the SA268 isolate. The genome of SA268 was almost identical to that of the Taiwanese ST59 CA-MRSA strains M013 and SA957. However, we observed several differences in gene composition, which included differences in the SCCmec element and several lipoprotein genes that were present in the Taiwanese strains but absent from SA268.

  18. Medical and household characteristics associated with methicillin resistant Staphylococcus aureus nasal carriage among patients admitted to a rural tertiary care hospital.

    Leah Schinasi

    Full Text Available BACKGROUND: Methicillin resistant Staphylococcus aureus (MRSA poses a threat to patient safety and public health. Understanding how MRSA is acquired is important for prevention efforts. This study investigates risk factors for MRSA nasal carriage among patients at an eastern North Carolina hospital in 2011. METHODS: Using a case-control design, hospitalized patients ages 18 - 65 years were enrolled between July 25, 2011 and December 15, 2011 at Vidant Medical Center, a tertiary care hospital that screens all admitted patients for nasal MRSA carriage. Cases, defined as MRSA nasal carriers, were age and gender matched to controls, non-MRSA carriers. In-hospital interviews were conducted, and medical records were reviewed to obtain information on medical and household exposures. Multivariable conditional logistic regression was used to derive odds ratio (OR estimates of association between MRSA carriage and medical and household exposures. RESULTS: In total, 117 cases and 119 controls were recruited to participate. Risk factors for MRSA carriage included having household members who took antibiotics or were hospitalized (OR: 3.27; 95% Confidence Interval (CI: 1.24-8.57 and prior hospitalization with a positive MRSA screen (OR: 3.21; 95% CI: 1.12-9.23. A lower proportion of cases than controls were previously hospitalized without a past positive MRSA screen (OR: 0.40; 95% CI: 0.19-0.87. CONCLUSION: These findings suggest that household exposures are important determinants of MRSA nasal carriage in hospitalized patients screened at admission.

  19. Antimicrobial activity of PVP from an Antarctic bacterium, Janthinobacterium sp. Ant5-2, on multi-drug and methicillin resistant Staphylococcus aureus

    Huang, Jonathan P.

    2012-04-11

    Multiple drug resistant (MDR) and methicillin-resistant Staphylococcus aureus (MRSA) have become increasingly prevalent as a community acquired infection. As a result limited treatment options are available with conventional synthetic antibiotics. Bioprospecting natural products with potent antimicrobial activity show promise for developing new drugs against this pathogen. In this study, we have investigated the antimicrobial activity of a purple violet pigment (PVP) from an Antarctic bacterium, Janthinobacterium sp. Ant5-2 on 15 clinical MDR and MRSA strains. The colorimetric resazurin assay was employed to determine the minimum inhibitory concentration (MIC90) of PVP against MDR and MRSA. The MIC90 ranged between 1.57 µg/mL and 3.13 µg/mL, which are significantly lower than many antimicrobials tested from natural sources against this pathogen. The spectrophotometrically determined growth analysis and total microscopic counts using Live/dead® BacLight™ fluorescent stain exhibited a steady decrease in viability of both MDR and MRSA cultures following treatment with PVP at the MIC levels. In silico predictive molecular docking study revealed that PVP could be a DNA-targeting minor groove binding antimicrobial compound. The continued development of novel antimicrobials derived from natural sources with the combination of a suite of conventional antibiotics could stem the rising pandemic of MDR and MRSA along with other deadly microbial pathogens.

  20. Biofilm Formation and Detection of IcaAB Genes in Clinical Isolates of Methicillin Resistant Staphylococcus aureus

    Fereshteh Eftekhar

    2011-03-01

    Full Text Available Objective(sMethicillin-resistant Staphylococcus aureus (MRSA is an important cause of nosocomial and community infections. Biofilm formation, mediated by a polysaccharide intercellular adhesin (PIA and encoded by the ica operon, is considered to be an important virulence factor in both S. epidermidis and S. aureus. However, the clinical impact of the ica locus and PIA production is less well described in S. aureus. We studied biofilm formation in clinical isolates of MRSA in relation to the presence of the ica operon. Materials and MethodsForty five MRSA were studied for biofilm formation by colony morphology on Congo red agar (CRA and the microtitre plate assay (MtP. Presence of the ica genes was detected by PCR and specific primers. ResultsThe results showed that 53.3% of the isolates had the potential to form biofilm by colony morphology of which, 75% carried the ica operon. Weak biofilm production was observed in the MtP assay by 57.8%, of which 53.8% harbored the ica operon. However, about 70% of biofilm non-producers also carried the ica operon. ConclusionOverall, there was no agreement between the icaAB gene carriage and biofilm phenotype by either of the two phenotypic methods. However, 91% of biofilm formers on CRA also produced biofilm in the MtP assay.

  1. Methicillin-resistant Staphylococcus aureus colonization in HIV-infected outpatients is common and detection is enhanced by groin culture.

    Peters, P J; Brooks, J T; Limbago, B; Lowery, H K; McAllister, S K; Mindley, R; Fosheim, G; Gorwitz, R J; Guest, J L; Hageman, J; Fridge, J; Rimland, D

    2011-07-01

    SUMMARYAlthough high rates of clinical infection with methicillin-resistant Staphylococcus aureus (MRSA) have been reported in HIV-infected adults, data on MRSA colonization are limited. We enrolled HIV-infected adults receiving care at the Atlanta VA Medical Center. Swabs from each participant's nares and groin were cultured with broth enrichment for S. aureus. Of 600 HIV-infected adults, 79 (13%) were colonized with MRSA and 180 (30%) with methicillin-susceptible S. aureus. MRSA pulsed-field gel electrophoresis types USA300 (n=44, 54%) and USA500/Iberian (n=29, 35%) predominated. Inclusion of groin swabs increased MRSA detection by 24% and USA300 detection by 38%. In multivariate analysis, MRSA colonization compared to no MRSA colonization was associated with a history of MRSA clinical infection, rarely or never using condoms, and contact with prisons and jails. In summary, the prevalence of MRSA colonization was high in this study of HIV-infected adults and detection of USA300 was enhanced by groin culture. PMID:20843384

  2. Community-Associated Methicillin-Resistant Staphylococcus aureus Lacking PVL, as a Cause of Severe Invasive Infection Treated with Linezolid

    Catarina Gouveia

    2013-01-01

    Full Text Available Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA is an emerging public health problem worldwide. Severe invasive infections have been described, mostly associated with the presence of Panton-Valentine leukocidin (PVL. In Portugal limited information exists regarding CA-MRSA infections. In this study we describe the case of a previously healthy 12-year-old female, sport athlete, who presented to the hospital with acetabulofemoral septic arthritis, myositis, fasciitis, acetabulum osteomyelitis, and pneumonia. The MRSA isolated from blood and synovial fluid was PVL negative and staphylococcal enterotoxin type P (SEP and type L (SEL positive, with a vancomycin MIC of 1.0 mg/L and resistant to clindamycin and ciprofloxacin. The patient was submitted to multiple surgical drainages and started on vancomycin, rifampicin, and gentamycin. Due to persistence of fever and no microbiological clearance, linezolid was started with improvement. This is one of the few reported cases of severe invasive infection caused by CA-MRSA in Portugal, which was successfully treated with linezolid. In spite of the severity of infection, the MRSA isolate did not produce PVL.

  3. Subtyping of Chilean Methicillin-Resistant Staphylococcus aureus strains carrying the staphylococcal cassette chromosome mec type I

    Gustavo Medina

    2012-09-01

    Full Text Available The cassette chromosome mec (SCCmec present in methicillin-resistant Staphylococcus aureus (MRSA has two essential components, the ccr gene complex and the mec gene complex. Additionally, SCCmec has non-essential components called J regions which are used for MRSA subtyping. This study was performed to determine subtypes MRSA strains carrying SCCmec type I based on polymorphism of regions located downstream of the mecA gene. A total of 98 MRSA strains carrying SCCmec type I isolated from patients hospitalized at the County Hospital of Valdivia (Chile between May 2007 and May 2008, were analyzed by multiplex PCR designed to amplify the mecA gene and 7 DNA hypervariable regions located around the mecA gene. MRSA strains were classified into seventeen genotypes accordingly to amplification patterns of DNA hypervariable regions. Five genotypes showed amplification patterns previously described. The remaining twelve genotypes showed new amplification patterns. Genotypes 18 and Genotype 19 were the most frequently detected. Regions HVR, Ins117 and pI258 stand out as being present in more than 60% of tested isolates. The acquisition of hypervariable regions by MRSA is a continuous horizontal transfer process through which the SCCmec have been preserved intact, or even may give rise to new types and subtypes of SCCmec. Therefore it is possible to infer that most MRSA strains isolated at the County Hospital of Valdivia (Chile were originated from two local clones which correspond to Genotype 18 and Genotype 19.

  4. Efficacy of Linezolid and Fosfomycin in Catheter-Related Biofilm Infection Caused by Methicillin-Resistant Staphylococcus aureus

    Dong Chai

    2016-01-01

    Full Text Available As long-standing clinical problems, catheter-related infections and other chronic biofilm infections are more difficult to treat due to the high antibiotic resistance of biofilm. Therefore, new treatments are needed for more effective bacteria clearance. In this study, we evaluated the antibacterial activities of several common antibiotics alone and their combinations against biofilm-embedded methicillin-resistant staphylococcus aureus (MRSA infections, both in vitro and in vivo. In brief, fosfomycin, levofloxacin, and rifampin alone or in combination with linezolid were tested in vitro against planktonic and biofilm-embedded MRSA infection in three MRSA stains. The synergistic effects between linezolid and the other three antibiotics were assessed by fractional inhibitory concentration index (FICI and time-kill curves, where the combination of linezolid plus fosfomycin showed the best synergistic effect in all strains. For further evaluation in vivo, we applied the combination of linezolid and fosfomycin in a catheter-related biofilm rat model and found that viable bacteria counts in biofilm were significantly reduced after treatment (P<0.05. In summary, we have shown here that the combination of linezolid and fosfomycin treatment had improved therapeutic effects on biofilm-embedded MRSA infection both in vitro and in vivo, which provided important basis for new clinical therapy development.

  5. Antibacterial and synergistic effects of Smallanthus sonchifolius leaf extracts against methicillin-resistant Staphylococcus aureus under light intensity.

    Joung, Hee; Kwon, Dong-Yeul; Choi, Jang-Gi; Shin, Dong-Young; Chun, Soon-Sil; Yu, Young-Beob; Shin, Dong-Won

    2010-04-01

    Smallanthus sonchifolius (yacon) is a perennial plant mostly cultivated in South America, primarily for use of the tubers as a food crop and the leaves as fodder for livestock. The antibacterial activities of the methanol extract of yacon leaves (S. sonchifolius) and its n-hexane, ethyl acetate, n-butanol and water fractions were evaluated against 6 strains of methicillin-resistant Staphylococcus aureus (MRSA) and 1 standard methicillin-susceptible S. aureus (MSSA) strain by using the disc diffusion method and minimal inhibitory concentrations (MICs) assay in the presence and absence of light. No activity was detected when the two methods were performed without light; however, under illumination at 4000 lux, the n-hexane fraction of yacon (HFY) had a MIC of 15.6 microg/ml. HFYL, prepared by exposure of HFY to 4000 lux for 18 h, was more effective than HFY in terms of antimicrobial activity against the 6 MRSA strains and 1 standard MSSA strain. HFYL mixed with ampicillin or oxacillin showed a synergistic effect with all fractional inhibitory concentrations values being below 0.5. The present study demonstrates the enhancement and antimicrobial activity of yacon leaves against MRSA in the presence of light. PMID:20119720

  6. Low incidence of livestock-associated methicillin-resistant Staphylococcus aureus bacteraemia in The Netherlands in 2009.

    Brigitte A G L van Cleef

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA is a worldwide problem in both hospitals and communities all over the world. In 2003, a new MRSA clade emerged with a reservoir in pigs and veal calves: livestock-associated MRSA (LA-MRSA. We wanted to estimate the incidence of bacteraemias due to LA-MRSA using national surveillance data from 2009 in the Netherlands. We found a low incidence of LA-MRSA and MRSA bacteraemia episodes, compared to bacteraemias caused by all S. aureus (0.04, 0.18 and 19.3 episodes of bacteraemia per 100,000 inhabitants per year, respectively. LA-MRSA and MRSA were uncommon compared to numbers from other countries as well. MRSA in general and LA-MRSA in specific does not appear to be a public health problem in the Netherlands now. The low incidence of LA-MRSA bacteraemia episodes may best be explained by differences in the populations affected by LA-MRSA versus other MRSA. However, reduced virulence of the strain involved, and the effectiveness of the search and destroy policy might play a role as well.

  7. Biofilm-Forming Methicillin-Resistant Staphylococcus aureus Survive in Kupffer Cells and Exhibit High Virulence in Mice

    Takuto Oyama

    2016-06-01

    Full Text Available Although Staphylococcus aureus is part of the normal body flora, heavy usage of antibiotics has resulted in the emergence of methicillin-resistant strains (MRSA. MRSA can form biofilms and cause indwelling foreign body infections, bacteremia, soft tissue infections, endocarditis, and osteomyelitis. Using an in vitro assay, we screened 173 clinical blood isolates of MRSA and selected 20 high-biofilm formers (H-BF and low-biofilm formers (L-BF. These were intravenously administered to mice and the general condition of mice, the distribution of bacteria, and biofilm in the liver, lung, spleen, and kidney were investigated. MRSA count was the highest in the liver, especially within Kupffer cells, which were positive for acid polysaccharides that are associated with intracellular biofilm. After 24 h, the general condition of the mice worsened significantly in the H-BF group. In the liver, bacterial deposition and aggregation and the biofilm-forming spot number were all significantly greater for H-BF group than for L-BF. CFU analysis revealed that bacteria in the H-BF group survived for long periods in the liver. These results indicate that the biofilm-forming ability of MRSA is a crucial factor for intracellular persistence, which could lead to chronic infections.

  8. Rhamnolipids as emulsifying agents for essential oil formulations: antimicrobial effect against Candida albicans and methicillin-resistant Staphylococcus aureus.

    Haba, Ester; Bouhdid, Samira; Torrego-Solana, Noelia; Marqués, A M; Espuny, M José; García-Celma, M José; Manresa, Angeles

    2014-12-10

    This work examines the influence of essential oil composition on emulsification with rhamnolipids and their use as therapeutic antimicrobial agents against two opportunistic pathogens, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. Rhamnolipids, produced by Pseudomonas aeruginosa, with waste frying oil as the carbon source, were composed of eight rhamnolipid homologues. The rhamnolipid mixture was used to produce emulsions containing essential oils (EOs) of Melaleuca alternifolia, Cinnamomum verum, Origanum compactum and Lavandula angustifolia using the titration method. Ternary phase diagrams were designed to evaluate emulsion stability, which differed depending on the essential oil. The in vitro antimicrobial activity of the EOs alone and the emulsions was evaluated. The antimicrobial activity presented by the essential oils alone increased with emulsification. The surface properties of rhamnolipids contribute to the positive dispersion of EOs and thus increase their availability and antimicrobial activity against C. albicans and S. aureus. Therefore, rhamnolipid-based emulsions represent a promising approach to the development of EO delivery systems. PMID:25269010

  9. Impact of admission screening for methicillin-resistant Staphylococcus aureus on the length of stay in an emergency department.

    Gilligan, P

    2010-06-01

    Preventing and controlling methicillin-resistant Staphylococcus aureus (MRSA) includes early detection and isolation. In the emergency department (ED), such measures have to be balanced with the requirement to treat patients urgently and transfer quickly to an acute hospital bed. We assessed, in a busy and overcrowded ED, the contribution made to a patient\\'s stay by previous MRSA risk group identification and by selective rescreening of those patients who were previously documented in the research hospital as being MRSA positive. Patients with a previous diagnosis of MRSA colonisation were flagged automatically as \\'risk group\\' (RG) on their arrival in the ED and were compared with \\'non-risk group\\' (NRG), i.e. not previously demonstrated in the research hospital to be infected or colonised with MRSA. Over an 18 month period, there were 16 456 admissions via the ED, of which 985 (6%) were RG patients. The expected median times to be admitted following a request for a ward bed for NRG and RG patients were 10.4 and 12.9h, respectively. Female sex, age >65 years, and RG status all independently predicted a statistically significantly longer stay in the ED following a request for a hospital bed. We consider that national and local policies for MRSA need to balance the welfare of patients in the ED with the need to comply with best practice, when there are inadequate ED and inpatient isolation facilities. Patients with MRSA requiring emergency admission must have a bed available for them.

  10. Synergistic Antibacterial Effect and Antibacterial Action Mode of Chitosan-Ferulic Acid Conjugate against Methicillin-Resistant Staphylococcus aureus.

    Eom, Sung-Hwan; Kang, Shin-Kook; Lee, Dae-Sung; Myeong, Jeong-In; Lee, Jinhwan; Kim, Hyun-Woo; Kim, Kyoung-Ho; Je, Jae-Young; Jung, Won-Kyo; Kim, Young-Mog

    2016-04-28

    We evaluated the synergistic antibacterial effect in combination with the chitosan-ferulic acid conjugate (CFA) and β-lactam antibiotics, such as ampicillin, penicillin, and oxacillin, against methicillin-resistant Staphylococcus aureus (MRSA) using fractional inhibitory concentration (FIC) indices. CFA clearly reversed the antibacterial activity of ampicillin, penicillin, and oxacillin against MRSA in the combination mode. Among these antibiotics, the combination of oxacillin-CFA resulted in a ∑FICmin range of 0.250 and ∑FICmax of 0.563, suggesting that the oxacillin-CFA combination resulted in an antibacterial synergy effect against MRSA. In addition, we determined that CFA inhibited the mRNA expression of gene mecA and the production of PBP2a, which is a key determinant for β-lactam antibiotic resistance, in a dosedependent manner. Thus, the results obtained in this study supported the idea on the antibacterial action mechanism that oxacillin will restore the antibacterial activity against MRSA through the suppression of PBP2a production by CFA. PMID:26718468

  11. Synergy of β-Lactams with Vancomycin against Methicillin-Resistant Staphylococcus aureus: Correlation of Disk Diffusion and Checkerboard Methods.

    Sy, Cheng Len; Huang, Tsi-Shu; Chen, Chii Shiang; Chen, Yao-Shen; Tsai, Hung-Chin; Wann, Shue-Renn; Wu, Kuan-Sheng; Chen, Jui-Kuang; Lee, Susan Shin-Jung; Liu, Yung-Ching

    2016-03-01

    Modified disk diffusion (MDD) and checkerboard tests were employed to assess the synergy of combinations of vancomycin and β-lactam antibiotics for 59 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Mu50 (ATCC 700699). Bacterial inocula equivalent to 0.5 and 2.0 McFarland standard were inoculated on agar plates containing 0, 0.5, 1, and 2 μg/ml of vancomycin. Oxacillin-, cefazolin-, and cefoxitin-impregnated disks were applied to the surface, and the zones of inhibition were measured at 24 h. The CLSI-recommended checkerboard method was used as a reference to detect synergy. The MICs for vancomycin were determined using the Etest method, broth microdilution, and the Vitek 2 automated system. Synergy was observed with the checkerboard method in 51% to 60% of the isolates when vancomycin was combined with any β-lactam. The fractional inhibitory concentration indices were significantly lower in MRSA isolates with higher vancomycin MIC combinations (P oxacillin, 45.1% and 52.4% for cefazolin, and 43.1% and 52.4% for cefoxitin when combined with 0.5 and 2 μg/ml of vancomycin, respectively. Based on our study, the simple MDD method is not recommended as a replacement for the checkerboard method to detect synergy. However, it may serve as an initial screening method for the detection of potential synergy when it is not feasible to perform other labor-intensive synergy tests. PMID:26677253

  12. Prevalence, antimicrobial resistance, and molecular characterization of methicillin-resistant Staphylococcus aureus from bulk tank milk of dairy herds.

    Kreausukon, K; Fetsch, A; Kraushaar, B; Alt, K; Müller, K; Krömker, V; Zessin, K-H; Käsbohrer, A; Tenhagen, B-A

    2012-08-01

    It was the objective of the study to estimate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in bulk tank milk from German dairy herds and to characterize isolates from bulk tank milk with respect to their Staph. aureus protein A (spa) and staphylococcal cassette chromosome mec (SCCmec) type, their phenotypic antimicrobial resistance and resistance- resp. virulence-associated genes using broth microdilution and a microarray for Staph. aureus. Bulk tank milk samples (25 mL) were tested for MRSA using a 2-step selective enrichment protocol. Presumptive MRSA were confirmed by PCR. Thirty-six isolates collected from bulk tank milk of dairy herds in 2009 and 2010 were included in the characterization. All isolates displayed spa-types assigned to the clonal complex CC398. Based on the epidemiological cut-off values for the interpretation of minimum inhibitory concentrations isolates were resistant to tetracycline (100%), clindamycin (58%), erythromycin (52%), quinupristin/dalfopristin (36%), and kanamycin (27%). Isolates did not carry genes associated with typical virulence factors for Staph. aureus such as the Panton-Valentine leukocidin. However, they did carry hemolysin genes. Livestock-associated MRSA of CC398 does occur in German dairy herds and the strains have similar properties as described for strains from pigs. PMID:22818451

  13. Molecular Detection of Methicillin-Resistant Staphylococcus aureus by Non-Protein Coding RNA-Mediated Monoplex Polymerase Chain Reaction

    Soo Yean, Cheryl Yeap; Selva Raju, Kishanraj; Xavier, Rathinam; Subramaniam, Sreeramanan; Gopinath, Subash C. B.; Chinni, Suresh V.

    2016-01-01

    Non-protein coding RNA (npcRNA) is a functional RNA molecule that is not translated into a protein. Bacterial npcRNAs are structurally diversified molecules, typically 50–200 nucleotides in length. They play a crucial physiological role in cellular networking, including stress responses, replication and bacterial virulence. In this study, by using an identified npcRNA gene (Sau-02) in Methicillin-resistant Staphylococcus aureus (MRSA), we identified the Gram-positive bacteria S. aureus. A Sau-02-mediated monoplex Polymerase Chain Reaction (PCR) assay was designed that displayed high sensitivity and specificity. Fourteen different bacteria and 18 S. aureus strains were tested, and the results showed that the Sau-02 gene is specific to S. aureus. The detection limit was tested against genomic DNA from MRSA and was found to be ~10 genome copies. Further, the detection was extended to whole-cell MRSA detection, and we reached the detection limit with two bacteria. The monoplex PCR assay demonstrated in this study is a novel detection method that can replicate other npcRNA-mediated detection assays. PMID:27367909

  14. Methicillin-resistant Staphylococcus epidermidis isolation from the vitrectomy specimen four hours after initial treatment with vancomycin and ceftazidime

    Golnaz Javey

    2010-02-01

    Full Text Available Golnaz Javey1, Stephen G Schwartz2, Andrew A Moshfeghi2, Sanjay Asrani3, Harry W Flynn Jr21Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX, USA; 2Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA; 3Department of Ophthalmology, Duke University Medical Center, Durham, NC, USAAbstract: A patient presented with acute-onset, postoperative endophthalmitis and visual acuity of light perception. Because of a time delay in arranging a pars plana vitrectomy (PPV, the patient was treated with a prompt vitreous tap for culture an injection of vancomycin and ceftazidime. Four hours later, the PPV was performed and additional antibiotics were injected. The cultures from both the initial needle tap and the subsequent PPV isolated methicillin-resistant Staphylococcus epidermidis sensitive to vancomycin, but resistant to fourth-generation fluoroquinolones. The patient eventually recovered a visual acuity of 20/80 before developing retinal detachment. This case illustrates the time lag necessary to sterilize the vitreous cavity, and suggests a possible two-step staged treatment strategy for situations in which access to PPV equipment and support staff may be limited.Keywords: endophthalmitis, pars plana vitrectomy, tap and inject

  15. Methicillin-Resistant Staphylococcus aureus in the Community in Luanda, Angola: Blurred Boundaries with the Hospital Setting.

    Conceição, Teresa; Coelho, Céline; Santos Silva, Isabel; de Lencastre, Hermínia; Aires-de-Sousa, Marta

    2016-01-01

    Although the nosocomial prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in Angola is over 60% and one of the highest in Africa, the extent of MRSA in the community is unknown. To fill this gap, we conducted a hospital-based study in which 158 children attending the emergency ward and ambulatory services of a pediatric hospital in Luanda, the capital of Angola, were screened for S. aureus nasal colonization. Overall, 70 (44.3%) individuals were colonized with S. aureus, of which 20 (28.6%) carried MRSA, resulting in a prevalence of 12.7% (20/158) of MRSA in the population screened. Molecular characterization by pulsed-field gel electrophoresis (PFGE), spa typing, multilocus sequence typing, and SCCmec typing distributed the isolates into two major MRSA clones and one dominant methicillin-susceptible S. aureus (MSSA) lineage, corresponding to the main clones circulating in hospitals in Luanda. The MRSA isolates mainly belonged to clones A (PFGE type A, spa type t105, ST5-IVa-65%) and B (PFGE B, t3869, ST88-IVa-30%), while MSSA isolates mainly belonged to clone L (PFGE type L, t861, ST508-42%). S. aureus isolates showed resistance to penicillin (96%), rifampin (87%), and trimethoprim-sulfamethoxazole (21%). In conclusion, the prevalence of MRSA among children in the community in Luanda is high and seems to originate from hospitals, warranting continuous monitoring and implementation of additional infection control measures. PMID:26505094

  16. Methicillin-resistant Staphylococcus aureus: laboratory detection methods in use in the Republic of Ireland and Northern Ireland.

    Humphreys, H

    2002-01-01

    There is no universally agreed laboratory protocol for the detection of methicillin-resistant Staphylococcus aureus (MRSA) and hence a variety of approaches are used. As part of an all-island survey of MRSA in the Republic of Ireland (the South) and Northern Ireland (the North), a questionnaire was circulated to 14 participating laboratories in the North and 49 in the South, to determine the methods used to isolate MRSA from clinical specimens, identify S. aureus and test for susceptibility to methicillin. Almost two-thirds (64%) of laboratories in the North but only 16% of laboratories in the South use enrichment culture. There is heavy reliance on commercial kits to confirm the identification of S. aureus in the South but all laboratories in the North use the staphylocoagulase test. More than 90% of all laboratories use a disc method for susceptibility testing and 71% of laboratories in the North supplement this with the E-test; however, a range of methicillin disk concentrations are in use. There is a need to review current laboratory methods used to detect MRSA, with follow-up audit on their implementation. Additional resources may be needed in some laboratories to comply with revised guidelines, and reference facilities are required to assess new commercially available techniques and to confirm the identification of unusual or difficult strains.

  17. Efficacy of Linezolid and Fosfomycin in Catheter-Related Biofilm Infection Caused by Methicillin-Resistant Staphylococcus aureus.

    Chai, Dong; Liu, Xu; Wang, Rui; Bai, Yan; Cai, Yun

    2016-01-01

    As long-standing clinical problems, catheter-related infections and other chronic biofilm infections are more difficult to treat due to the high antibiotic resistance of biofilm. Therefore, new treatments are needed for more effective bacteria clearance. In this study, we evaluated the antibacterial activities of several common antibiotics alone and their combinations against biofilm-embedded methicillin-resistant staphylococcus aureus (MRSA) infections, both in vitro and in vivo. In brief, fosfomycin, levofloxacin, and rifampin alone or in combination with linezolid were tested in vitro against planktonic and biofilm-embedded MRSA infection in three MRSA stains. The synergistic effects between linezolid and the other three antibiotics were assessed by fractional inhibitory concentration index (FICI) and time-kill curves, where the combination of linezolid plus fosfomycin showed the best synergistic effect in all strains. For further evaluation in vivo, we applied the combination of linezolid and fosfomycin in a catheter-related biofilm rat model and found that viable bacteria counts in biofilm were significantly reduced after treatment (P fosfomycin treatment had improved therapeutic effects on biofilm-embedded MRSA infection both in vitro and in vivo, which provided important basis for new clinical therapy development. PMID:27366751

  18. Potentiation activity of multiple antibacterial agents by Salvianolate from the Chinese medicine Danshen against methicillin-resistant Staphylococcus aureus (MRSA).

    Liu, Qing-Qing; Han, Jun; Zuo, Guo-Ying; Wang, Gen-Chun; Tang, Hua-Shu

    2016-05-01

    Salvianolate (SAL) is a prescribed medicine from the Chinese herb Danshen (Salvia miltiorrhiza Bunge). It has been widely used in treatment of coronary and other diseases with significant effects. The in vitro antimicrobial activities of SAL against infectious pathogens were assayed and its combined effects on 10 clinical isolates of SCCmec III type methicillin-resistant Staphylococcus aureus (MRSA) with ten antibiotics were evaluated. Susceptibility to each agent alone was tested using a broth microdilution method, and the chequerboard and time-kill experiments were used for the combined activities. The results showed MIC was 128-256 mg/L for SAL used alone against MRSA. Significant synergies were observed for SAL/Ampicillin (Fosfomycin, Erythromycin, Piperacillin-tazobactam or Clindamycin) combination against over half of the isolates, with their MICs reduced by times of dilution (TOD) to 4-32 (FICIs 0.375-0.5), respectively. SAL/AMP combination showed the best combined effect of synergy on bacteriostatic and bactericidal activities, while SAL/AMK combination reversed the resistance of MRSA to AMK. The results demonstrated that SAL enhanced widely the in vitro anti-MRSA efficacy of the ten antibacterial agents, which had potential for combinatory therapy of patients infected with MRSA and warrants further investigations. PMID:26639445

  19. Evaluation of rep-PCR/DiversiLab versus PFGE and spa typing in genotyping methicillin-resistant Staphylococcus aureus (MRSA).

    Aguadero, V; González Velasco, C; Vindel, A; Gonzalez Velasco, M; Moreno, J J

    2015-01-01

    Pulsed-field gel electrophoresis (PFGE) is the 'gold standard' for genotyping of methicillin-resistant Staphylococcus aureus (MRSA); however, the DiversiLab (DL) system, based on rep-PCR, is faster, simpler and could be better adapted to daily routine hospital work. We genotyped 100 MRSA isolates using PFGE, DL, and spa typing, and evaluated the discriminatory power of each technique and the correlation between them by Simpson's index(SI) and adjusted Rand coefficient (ARI), respectively. The isolates were from clinical samples from eight hospitals in Extremadura (Spain) during 2010. DL separated the 100 MRSA into 18 patterns, with 69% of the isolates grouped into four predominant patterns. spa typing reported 17 spa types, classifying 69% of MRSA into two major types (t067 and t002). PFGE revealed the existence of 27 patterns, gathering 54% of MRSA into three pulse types (E8a, E7a and E7b). SI values were 0.819, 0.726, 0.887 and 0.460 for DL, spa typing, PFGE and CC-BURP, respectively. ARI values of DL over PFGE, spa typing and CC-BURP were 0.151, 0.321 and 0.071, respectively. DL has less discriminatory power than PFGE but more than spa typing. The concordance of DL with PFGE is low, primarily because DL does not discriminate between the three predominant MRSA pulse types in our environment. PMID:26510268

  20. Methicillin-resistant Staphylococcus aureus nasal cariage among hospitalized patients and healthcare workers in the Clinical center of Serbia

    Ćirković Ivana

    2014-01-01

    Full Text Available The aim of the present study was to provide the first comprehensive analysis of methicillin-resistant Staphylococcus aureus (MRSA carriage among patients and healthcare workers (HCWs in the largest healthcare facility in Serbia. Specimens from anterior nares obtained from 195 hospitalized patients and 105 HCWs were inoculated after broth enrichment onto chromogenic MRSA-ID medium. In total, 21 of 300 specimens yielded MRSA. Among hospitalized patients, 7.7% were colonized with MRSA, and 5.7% HCWs were colonized with MRSA. Five out of 21 (23.8% tested MRSA strains were classified as community-associated MRSA (CA-MRSA, and four of them were isolated from HCWs. The remaining 16 MRSA strains had characteristics of healthcare-associated MRSA (HA-MRSA, and two of them were isolated from HCWs. The HA-MRSA strains isolated from HCWs were indistinguishable from HA-MRSA of the same cluster isolated from patients. This finding reveals the circulation of HA-MRSA strains between patients and HCWs in the Clinical Center of Serbia. [Projekat Ministarstva nauke Republike Srbije, br. ON 175039