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Sample records for invasive staphylococcus aureus

  1. Staphylococcus aureus

    Science.gov (United States)

    Arduino, Jean Marie; Kaye, Keith S; Reed, Shelby D; Peter, Senaka A; Sexton, Daniel J; Chen, Luke F; Hardy, N Chantelle; Tong, Steven Yc; Smugar, Steven S; Fowler, Vance G; Anderson, Deverick J

    2015-01-01

    Staphylococcus aureus is the most common and most important pathogen following knee and hip arthroplasty procedures. Understanding the epidemiology of invasive S. aureus infections is important to quantify this serious complication. This nested retrospective cohort analysis included adult patients who had undergone insertion of knee or hip prostheses with clean or clean-contaminated wound class at 11 hospitals between 2003-2006. Invasive S. aureus infections, non-superficial incisional surgical site infections (SSIs) and blood stream infections (BSIs), were prospectively identified following each procedure. Prevalence rates, per 100 procedures, were estimated. 13,719 prosthetic knee (62%) and hip (38%) insertion procedures were performed. Of 92 invasive S. aureus infections identified, SSIs were more common (80%) than SSI and BSI (10%) or BSI alone (10%). The rate of invasive S. aureus infection/100 procedures was 0.57 [95% CI: 0.43-0.73] for knee insertion and 0.83 [95% CI: 0.61-1.08] for hip insertion. More than half (53%) were methicillin-resistant. Median time-to-onset of infection was 34 and 26 days for knee and hip insertion, respectively. Infection was associated with higher National Healthcare Safety Network risk index (p ≤ 0.0001). Post-operative invasive S. aureus infections were rare, but difficult-to-treat methicillin-resistant infections were relatively common. Optimizing preventative efforts may greatly reduce the healthcare burden associated with S. aureus infections.

  2. Invasive Staphylococcus aureus infection in an African adolescent ...

    African Journals Online (AJOL)

    Staphylococcus aureus remains an important cause of mortality, in the community and health care set-ups. S. aureus strains with genes encoding lethal toxins and culture negative sepsis augment the diagnostic challenge in resource limited settings. With a growing rate of resistance to the causative bacteria and atypical ...

  3. Systemic Staphylococcus aureus infection mediated by Candida albicans hyphal invasion of mucosal tissue

    NARCIS (Netherlands)

    Schlecht, L.M.; Peters, B.M.; Krom, B.P.; Freiberg, J.A.; Hänsch, G.M.; Filler, S.G.; Jabra-Rizk, M.A.; Shirtliff, M.E.

    2015-01-01

    Candida albicans and Staphylococcus aureus are often co-isolated in cases of biofilm-associated infections. C. albicans can cause systemic disease through morphological switch from the rounded yeast to the invasive hyphal form. Alternatively, systemic S. aureus infections arise from seeding through

  4. Heterologously expressed Staphylococcus aureus fibronectin-binding proteins are sufficient for invasion of host cells

    NARCIS (Netherlands)

    Sinha, B; Francois, P; Que, Y A; Hussain, M; Heilmann, C; Moreillon, P; Lew, D; Krause, K H; Peters, Georg; Herrmann, M

    2000-01-01

    Staphylococcus aureus invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, critically depends on fibronectin bridging between S. aureus fibronectin-binding proteins (FnBPs) and the host fibronectin receptor integrin alpha(5)beta(1) (B. Sinha et al., Cell.

  5. Staphylococcus aureus

    Science.gov (United States)

    Pietrocola, Giampiero; Nobile, Giulia; Rindi, Simonetta; Speziale, Pietro

    2017-01-01

    Neutrophils, complement system and skin collectively represent the main elements of the innate immune system, the first line of defense of the host against many common microorganisms. Bacterial pathogens have evolved strategies to counteract all these defense activities. Specifically, Staphylococcus aureus , a major human pathogen, secretes a variety of immune evasion molecules including proteases, which cleave components of the innate immune system or disrupt the integrity of extracellular matrix and intercellular connections of tissues. Additionally, S. aureus secretes proteins that can activate host zymogens which, in turn, target specific defense components. Secreted proteins can also inhibit the anti-bacterial function of neutrophils or complement system proteases, potentiating S. aureus chances of survival. Here, we review the current understanding of these proteases and modulators of host proteases in the functioning of innate immunity and describe the importance of these mechanisms in the pathology of staphylococcal diseases.

  6. Staphylococcus aureus

    Science.gov (United States)

    Balamurugan, P; Praveen Krishna, V; Bharath, D; Lavanya, Raajaraam; Vairaprakash, Pothiappan; Adline Princy, S

    2017-01-01

    Staphylococcus aureus is a widely acknowledged Gram-positive pathogen for forming biofilm and virulence gene expressions by quorum sensing (QS), a cell to cell communication process. The quorum regulator SarA of S. aureus up-regulates the expression of many virulence factors including biofilm formation to mediate pathogenesis and evasion of the host immune system in the late phases of growth. Thus, inhibiting the production or blocking SarA protein might influence the down-regulation of biofilm and virulence factors. In this context, here we have synthesized 2-[(Methylamino)methyl]phenol, which was specifically targeted toward the quorum regulator SarA through in silico approach in our previous study. The molecule has been evaluated in vitro to validate its antibiofilm activity against clinical S. aureus strains. In addition, antivirulence properties of the inhibitor were confirmed with the observation of a significant reduction in the expression of representative virulence genes like fnbA, hla and hld that are governed under S. aureus QS. Interestingly, the SarA targeted inhibitor showed negligible antimicrobial activity and markedly reduced the minimum inhibitory concentration of conventional antibiotics when used in combination making it a more attractive lead for further clinical tests.

  7. A Prophage in Diabetic Foot Ulcer-Colonizing Staphylococcus aureus Impairs Invasiveness by Limiting Intracellular Growth.

    Science.gov (United States)

    Rasigade, Jean-Philippe; Dunyach-Rémy, Catherine; Sapin, Anaïs; Messad, Nourredine; Trouillet-Assant, Sophie; Dupieux, Céline; Lavigne, Jean-Philippe; Laurent, Frédéric

    2016-11-15

    The mechanisms that drive the transition from commensality to invasiveness in Staphylococcus aureus are poorly understood. We recently reported that >50% of S. aureus isolates from uninfected diabetic foot ulcers in French patients harbor a prophage, ROSA-like, that is absent from invasive isolates from diabetic foot infections, including osteomyelitis. Here we show that the ROSA-like insertion abolishes the ability of S. aureus to replicate within osteoblasts, the bone-forming cells, greatly reducing damage to infected cells. These results unravel an important mechanism by which particular S. aureus strains are maintained in a commensal state in diabetic foot ulcers. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  8. Adhesion, invasion and evasion: the many functions of the surface proteins of Staphylococcus aureus

    Science.gov (United States)

    Foster, Timothy J.; Geoghegan, Joan A.; Ganesh, Vannakambadi K.; Höök, Magnus

    2014-01-01

    Staphylococcus aureus is an important opportunistic pathogen and persistently colonizes about 20% of the human population. Its surface is ‘decorated’ with proteins that are covalently anchored to the cell wall peptidoglycan. Structural and functional analysis has identified four distinct classes of surface proteins, of which microbial surface component recognizing adhesive matrix molecules (MSCRAMMs) are the largest class. These surface proteins have numerous functions, including adhesion to and invasion of host cells and tissues, evasion of immune responses and biofilm formation. Thus, cell wall-anchored proteins are essential virulence factors for the survival of S. aureus in the commensal state and during invasive infections, and targeting them with vaccines could combat S. aureus infections. PMID:24336184

  9. Inhibition of Staphylococcus aureus invasion into bovine mammary epithelial cells by contact with live Lactobacillus casei.

    Science.gov (United States)

    Bouchard, Damien S; Rault, Lucie; Berkova, Nadia; Le Loir, Yves; Even, Sergine

    2013-02-01

    Staphylococcus aureus is a major pathogen that is responsible for mastitis in dairy herds. S. aureus mastitis is difficult to treat and prone to recurrence despite antibiotic treatment. The ability of S. aureus to invade bovine mammary epithelial cells (bMEC) is evoked to explain this chronicity. One sustainable alternative to treat or prevent mastitis is the use of lactic acid bacteria (LAB) as mammary probiotics. In this study, we tested the ability of Lactobacillus casei strains to prevent invasion of bMEC by two S. aureus bovine strains, RF122 and Newbould305, which reproducibly induce acute and moderate mastitis, respectively. L. casei strains affected adhesion and/or internalization of S. aureus in a strain-dependent manner. Interestingly, L. casei CIRM-BIA 667 reduced S. aureus Newbould305 and RF122 internalization by 60 to 80%, and this inhibition was confirmed for two other L. casei strains, including one isolated from bovine teat canal. The protective effect occurred without affecting bMEC morphology and viability. Once internalized, the fate of S. aureus was not affected by L. casei. It should be noted that L. casei was internalized at a low rate but survived in bMEC cells with a better efficiency than that of S. aureus RF122. Inhibition of S. aureus adhesion was maintained with heat-killed L. casei, whereas contact between live L. casei and S. aureus or bMEC was required to prevent S. aureus internalization. This first study of the antagonism of LAB toward S. aureus in a mammary context opens avenues for the development of novel control strategies against this major pathogen.

  10. Inhibition of Staphylococcus aureus Invasion into Bovine Mammary Epithelial Cells by Contact with Live Lactobacillus casei

    Science.gov (United States)

    Bouchard, Damien S.; Rault, Lucie; Berkova, Nadia; Le Loir, Yves

    2013-01-01

    Staphylococcus aureus is a major pathogen that is responsible for mastitis in dairy herds. S. aureus mastitis is difficult to treat and prone to recurrence despite antibiotic treatment. The ability of S. aureus to invade bovine mammary epithelial cells (bMEC) is evoked to explain this chronicity. One sustainable alternative to treat or prevent mastitis is the use of lactic acid bacteria (LAB) as mammary probiotics. In this study, we tested the ability of Lactobacillus casei strains to prevent invasion of bMEC by two S. aureus bovine strains, RF122 and Newbould305, which reproducibly induce acute and moderate mastitis, respectively. L. casei strains affected adhesion and/or internalization of S. aureus in a strain-dependent manner. Interestingly, L. casei CIRM-BIA 667 reduced S. aureus Newbould305 and RF122 internalization by 60 to 80%, and this inhibition was confirmed for two other L. casei strains, including one isolated from bovine teat canal. The protective effect occurred without affecting bMEC morphology and viability. Once internalized, the fate of S. aureus was not affected by L. casei. It should be noted that L. casei was internalized at a low rate but survived in bMEC cells with a better efficiency than that of S. aureus RF122. Inhibition of S. aureus adhesion was maintained with heat-killed L. casei, whereas contact between live L. casei and S. aureus or bMEC was required to prevent S. aureus internalization. This first study of the antagonism of LAB toward S. aureus in a mammary context opens avenues for the development of novel control strategies against this major pathogen. PMID:23183972

  11. Prevalence of clonal complexes and virulence genes among commensal and invasive Staphylococcus aureus isolates in Sweden.

    Directory of Open Access Journals (Sweden)

    Gunlög Rasmussen

    Full Text Available Staphylococcus aureus encodes a remarkable number of virulence factors which may contribute to its pathogenicity and ability to cause invasive disease. The main objective of this study was to evaluate the association between S. aureus invasiveness and bacterial genotype, in terms of the presence of virulence genes and affiliation to clonal complexes. Also, the significance of different virulence genes, mainly adhesins, for the development of infective endocarditis was investigated. DNA microarray technology was used to analyze 134 S. aureus isolates, all methicillin-susceptible, derived from three groups of clinically well-characterized patients: nasal carriers (n=46, bacteremia (n=55, and bacteremia with infective endocarditis (n=33. Invasive isolates were dominant in four of the major clonal complexes: 5, 8, 15, and 25. Of the 170 virulence genes examined, those encoding accessory gene regulator group II (agr II, capsule polysaccharide serotype 5 (cap5, and adhesins such as S. aureus surface protein G (sasG and fibronectin-binding protein B (fnbB were found to be associated with invasive disease. The same was shown for the leukocidin genes lukD/lukE, as well as the genes encoding serine protease A and B (splA/splB, staphylococcal complement inhibitor (scn and the staphylococcal exotoxin-like protein (setC or selX. In addition, there was a trend of higher prevalence of certain genes or gene clusters (sasG, agr II, cap5 among isolates causing infective endocarditis compared to other invasive isolates. In most cases, the presence of virulence genes was linked to clonal complex affiliation. In conclusion, certain S. aureus clonal lineages harboring specific sets of virulence genes seem to be more successful in causing invasive disease.

  12. Biofilm formation in invasive Staphylococcus aureus isolates is associated with the clonal lineage.

    Science.gov (United States)

    Naicker, Preneshni R; Karayem, Karayem; Hoek, Kim G P; Harvey, Justin; Wasserman, Elizabeth

    2016-01-01

    The contribution of the genetic background of Staphylococcus aureus to biofilm formation is poorly understood. We investigated the association between the genetic background and the biofilm forming ability of clinical invasive S. aureus isolates. Secondary objectives included investigating any correlation with biofilm formation and methicillin resistance or the source of bacteraemia. The study was conducted at a 1300-bed tertiary hospital in Cape Town, South Africa. S. aureus isolates obtained from blood cultures between January 2010 and January 2012 were included. Genotypic characterization was performed by PFGE, spa typing, SCCmec typing and MLST. Thirty genotypically unique strains were assessed for phenotypic biofilm formation with the microtitre plate assay. All isolates were tested in triplicate and an average optical density, measured at a wavelength of 490 nm, was determined. The biofilm forming ability of isolates with A490 ≤ 0.17 were considered non-adherent, A490 > 0.17 'weak positive' and A490 > 0.34 'strong positive'. Fifty seven percent of isolates formed biofilms. Weak biofilm formation occurred in 40% (n = 12) and strong biofilm formation in 17% (n = 5) of isolates. All 5 isolates capable of strong biofilm formation belong to one spa clonal complex (spa-CC 064). Strains from spa-CC 064 were capable of higher biofilm formation than other spa clonal complexes (p = 0.00002). These 5 strains belonged to MLST CC5 and CC8. Biofilm formation correlates with the spa clonal lineage in our population of invasive S. aureus strains. Biofilm formation did not correlate with methicillin resistance and was not related to the source of bacteraemia. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Geographic distribution of Staphylococcus aureus causing invasive infections in Europe: a molecular-epidemiological analysis.

    Directory of Open Access Journals (Sweden)

    Hajo Grundmann

    2010-01-01

    Full Text Available Staphylococcus aureus is one of the most important human pathogens and methicillin-resistant variants (MRSAs are a major cause of hospital and community-acquired infection. We aimed to map the geographic distribution of the dominant clones that cause invasive infections in Europe.In each country, staphylococcal reference laboratories secured the participation of a sufficient number of hospital laboratories to achieve national geo-demographic representation. Participating laboratories collected successive methicillin-susceptible (MSSA and MRSA isolates from patients with invasive S. aureus infection using an agreed protocol. All isolates were sent to the respective national reference laboratories and characterised by quality-controlled sequence typing of the variable region of the staphylococcal spa gene (spa typing, and data were uploaded to a central database. Relevant genetic and phenotypic information was assembled for interactive interrogation by a purpose-built Web-based mapping application. Between September 2006 and February 2007, 357 laboratories serving 450 hospitals in 26 countries collected 2,890 MSSA and MRSA isolates from patients with invasive S. aureus infection. A wide geographical distribution of spa types was found with some prevalent in all European countries. MSSA were more diverse than MRSA. Genetic diversity of MRSA differed considerably between countries with dominant MRSA spa types forming distinctive geographical clusters. We provide evidence that a network approach consisting of decentralised typing and visualisation of aggregated data using an interactive mapping tool can provide important information on the dynamics of MRSA populations such as early signalling of emerging strains, cross border spread, and importation by travel.In contrast to MSSA, MRSA spa types have a predominantly regional distribution in Europe. This finding is indicative of the selection and spread of a limited number of clones within health care

  14. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

    NARCIS (Netherlands)

    A.F. Brown (Aisling F.); A.G. Murphy (Alison G.); S.J. Lalor (Stephen J.); J.M. Leech (John M.); K.M. O’Keeffe (Kate M.); M. Mac Aogáin (Micheál); D.P. O’Halloran (Dara P.); K.A. Lacey (Keenan A.); M. Tavakol (Mehri); C.H. Hearnden (Claire H.); D. Fitzgerald-Hughes (Deirdre); H. Humphreys (Hilary); J.P. Fennell (Jérôme P.); W.J.B. van Wamel (Willem); T.J. Foster (Timothy J.); J.A. Geoghegan (Joan A.); E.C. Lavelle (Ed C.); T.R. Rogers (Thomas R.); R.M. McLoughlin (Rachel M.)

    2015-01-01

    textabstractMechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we

  15. Inhibition of Staphylococcus aureus Invasion into Bovine Mammary Epithelial Cells by Contact with Live Lactobacillus casei

    OpenAIRE

    Bouchard, Damien S.; Rault, Lucie; Berkova, Nadia; Le Loir, Yves; Even, Sergine

    2013-01-01

    Staphylococcus aureus is a major pathogen that is responsible for mastitis in dairy herds. S. aureus mastitis is difficult to treat and prone to recurrence despite antibiotic treatment. The ability of S. aureus to invade bovine mammary epithelial cells (bMEC) is evoked to explain this chronicity. One sustainable alternative to treat or prevent mastitis is the use of lactic acid bacteria (LAB) as mammary probiotics. In this study, we tested the ability of Lactobacillus casei strains to prevent...

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

    Science.gov (United States)

    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.

  17. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

    Science.gov (United States)

    Lalor, Stephen J.; Leech, John M.; O’Keeffe, Kate M.; Mac Aogáin, Micheál; O’Halloran, Dara P.; Lacey, Keenan A.; Tavakol, Mehri; Hearnden, Claire H.; Fitzgerald-Hughes, Deirdre; Humphreys, Hilary; Fennell, Jérôme P.; van Wamel, Willem J.; Foster, Timothy J.; Geoghegan, Joan A.; Lavelle, Ed C.; Rogers, Thomas R.; McLoughlin, Rachel M.

    2015-01-01

    Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans. PMID:26539822

  18. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection.

    LENUS (Irish Health Repository)

    Brown, Aisling F

    2015-01-01

    Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans.

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

    Directory of Open Access Journals (Sweden)

    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. Fibrinogen and fibronectin binding cooperate for valve infection and invasion in Staphylococcus aureus experimental endocarditis

    NARCIS (Netherlands)

    Que, Yok-Ai; Haefliger, Jacques-Antoine; Piroth, Lionel; François, Patrice; Widmer, Eleonora; Entenza, José M; Sinha, Bhanu; Herrmann, Mathias; Francioli, Patrick; Vaudaux, Pierre; Moreillon, Philippe

    2005-01-01

    The expression of Staphylococcus aureus adhesins in Lactococcus lactis identified clumping factor A (ClfA) and fibronectin-binding protein A (FnBPA) as critical for valve colonization in rats with experimental endocarditis. This study further analyzed their role in disease evolution. Infected

  1. Staphylococcus aureus keratinocyte invasion is dependent upon multiple high-affinity fibronectin-binding repeats within FnBPA.

    Directory of Open Access Journals (Sweden)

    Andrew M Edwards

    2011-04-01

    Full Text Available Staphylococcus aureus is a commensal organism and a frequent cause of skin and soft tissue infections, which can progress to serious invasive disease. This bacterium uses its fibronectin binding proteins (FnBPs to invade host cells and it has been hypothesised that this provides a protected niche from host antimicrobial defences, allows access to deeper tissues and provides a reservoir for persistent or recurring infections. FnBPs contain multiple tandem fibronectin-binding repeats (FnBRs which bind fibronectin with varying affinity but it is unclear what selects for this configuration. Since both colonisation and skin infection are dependent upon the interaction of S. aureus with keratinocytes we hypothesised that this might select for FnBP function and thus composition of the FnBR region. Initial experiments revealed that S. aureus attachment to keratinocytes is rapid but does not require FnBRs. By contrast, invasion of keratinocytes was dependent upon the FnBR region and occurred via similar cellular processes to those described for endothelial cells. Despite this, keratinocyte invasion was relatively inefficient and appeared to include a lag phase, most likely due to very weak expression of α(5β(1 integrins. Molecular dissection of the role of the FnBR region revealed that efficient invasion of keratinocytes was dependent on the presence of at least three high-affinity (but not low-affinity FnBRs. Over-expression of a single high-affinity or three low-affinity repeats promoted invasion but not to the same levels as S. aureus expressing an FnBPA variant containing three high-affinity repeats. In summary, invasion of keratinocytes by S. aureus requires multiple high-affinity FnBRs within FnBPA, and given the importance of the interaction between these cell types and S. aureus for both colonisation and infection, may have provided the selective pressure for the multiple binding repeats within FnBPA.

  2. Impact of sub-inhibitory antibiotics on fibronectin-mediated host cell adhesion and invasion by Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Rasigade Jean

    2011-12-01

    Full Text Available Abstract Background Staphylococcus aureus is a well-armed pathogen prevalent in severe infections such as endocarditis and osteomyelitis. Fibronectin-binding proteins A and B, encoded by fnbA/B, are major pathogenesis determinants in these infections through their involvement in S. aureus adhesion to and invasion of host cells. Sub-minimum inhibitory concentrations (sub-MICs of antibiotics, frequently occurring in vivo because of impaired drug diffusion at the infection site, can alter S. aureus phenotype. We therefore investigated their impact on S. aureus fibronectin-mediated adhesiveness and invasiveness. Methods After in vitro challenge of S. aureus 8325-4 and clinical isolates with sub-MICs of major anti-staphylococcal agents, we explored fnbA/B transcription levels, bacterial adhesiveness to immobilised human fibronectin and human osteoblasts in culture, and bacterial invasion of human osteoblasts. Results Oxacillin, moxifloxacin and linezolid led to the development of a hyper-adhesive phenotype in the fibronectin adhesion assay that was consistent with an increase in fnbA/B transcription. Conversely, rifampin treatment decreased fibronectin binding in all strains tested without affecting fnbA/B transcription. Gentamicin and vancomycin had no impact on fibronectin binding or fnbA/B transcription levels. Only oxacillin-treated S. aureus displayed a significantly increased adhesion to cultured osteoblasts, but its invasiveness did not differ from that of untreated controls. Conclusion Our findings demonstrate that several antibiotics at sub-MICs modulate fibronectin binding in S. aureus in a drug-specific fashion. However, hyper- and hypo- adhesive phenotypes observed in controlled in vitro conditions were not fully confirmed in whole cell infection assays. The relevance of adhesion modulation during in vivo infections is thus still uncertain and requires further investigations.

  3. Staphylococcus aureus Transcriptome Architecture

    DEFF Research Database (Denmark)

    Mäder, Ulrike; Nicolas, Pierre; Depke, Maren

    2016-01-01

    Staphylococcus aureus is a major pathogen that colonizes about 20% of the human population. Intriguingly, this Gram-positive bacterium can survive and thrive under a wide range of different conditions, both inside and outside the human body. Here, we investigated the transcriptional adaptation of...

  4. Antimicrobial resistant coagulase positive Staphylococcus aureus ...

    African Journals Online (AJOL)

    Staphylococcus aureus is an Important agent of food poisoning. In many countries, it is the main bacterial organism responsible for diseases caused by exotoxin production and direct invasion with systemic dissemination. In poultry, S. aureus is associated with many clinical syndromes including tenosynovitis, omphalitis, ...

  5. Staphylococcus aureus host cell invasion and virulence in sepsis is facilitated by the multiple repeats within FnBPA.

    Directory of Open Access Journals (Sweden)

    Andrew M Edwards

    2010-06-01

    Full Text Available Entry of Staphylococcus aureus into the bloodstream can lead to metastatic abscess formation and infective endocarditis. Crucial to the development of both these conditions is the interaction of S. aureus with endothelial cells. In vivo and in vitro studies have shown that the staphylococcal invasin FnBPA triggers bacterial invasion of endothelial cells via a process that involves fibronectin (Fn bridging to alpha(5beta(1 integrins. The Fn-binding region of FnBPA usually contains 11 non-identical repeats (FnBRs with differing affinities for Fn, which facilitate the binding of multiple Fn molecules and may promote integrin clustering. We thus hypothesized that multiple repeats are necessary to trigger the invasion of endothelial cells by S. aureus. To test this we constructed variants of fnbA containing various combinations of FnBRs. In vitro assays revealed that endothelial cell invasion can be facilitated by a single high-affinity, but not low-affinity FnBR. Studies using a nisin-inducible system that controlled surface expression of FnBPA revealed that variants encoding fewer FnBRs required higher levels of surface expression to mediate invasion. High expression levels of FnBPA bearing a single low affinity FnBR bound Fn but did not invade, suggesting that FnBPA affinity for Fn is crucial for triggering internalization. In addition, multiple FnBRs increased the speed of internalization, as did higher expression levels of FnBPA, without altering the uptake mechanism. The relevance of these findings to pathogenesis was demonstrated using a murine sepsis model, which showed that multiple FnBRs were required for virulence. In conclusion, multiple FnBRs within FnBPA facilitate efficient Fn adhesion, trigger rapid bacterial uptake and are required for pathogenesis.

  6. Methicillin-resistant Staphylococcus aureus as a cause of invasive infections in Central Africa: a case report and review of the literature

    NARCIS (Netherlands)

    Huson, M. A. M.; Kalkman, R.; Remppis, J.; Beyeme, J. O.; Kraef, C.; Schaumburg, F.; Alabi, A. S.; Grobusch, M. P.

    2014-01-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) colonization and infection are increasingly being reported worldwide and are associated with severe illness. The vast majority of MRSA infections are skin and soft tissue infections, while invasive disease remains rare. In

  7. Effects of vitamin D and its metabolites on cell viability and Staphylococcus aureus invasion in bovine mammary epithelial cells

    DEFF Research Database (Denmark)

    Yue, Yuan; Hymøller, Lone; Jensen, Søren Krogh

    2017-01-01

    and D3 compounds on bovine mammary epithelial cell proliferation and Staphylococcus aureus (S. aureus) invasion.. Results showed that 1,25-dihydroxyvitamin D2 have an anti-proliferation activity comparable to 1,25-dihydroxyvitamin D3, while D2 and 25-hydroxyvitamin D2 (25(OH)D2) was slightly more potent......, and E-cadherin did not change. Additionally, the induction of CYP24A1 expression by 25(OH)D3 was higher than that of 25(OH)D2, which may contribute to the differences in anti-proliferation activity. S. aureus invaded into MAC-T cells and universally inhibited gene expressions. MAC-T cells pre......Vitamin D has been found have various biological effects that may be potent in preventing bovine mastitis. Two forms of vitamin D, vitamin D2 (D2) and vitamin D3 (D3), can be hydroxylated to functional metabolites in cattle. The objectives of the present study were to investigate the effects of D2...

  8. The evolution of Staphylococcus aureus

    NARCIS (Netherlands)

    Deurenberg, Ruud H; Stobberingh, Ellen E

    2008-01-01

    A broad variety of infections, ranging from minor infections of the skin to post-operative wound infections can be caused by Staphylococcus aureus. The adaptive power of S. aureus to antibiotics leaded, in the early 1960s, to the emergence of methicillin-resistant S. aureus (MRSA). The cause of

  9. Community-Associated Methicillin-Resistant Staphylococcus aureus Lacking PVL, as a Cause of Severe Invasive Infection Treated with Linezolid

    Directory of Open Access Journals (Sweden)

    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.

  10. Hospital and provider patient volumes, cesarean section rates, and early postpartum invasive methicillin-resistant Staphylococcus aureus infection.

    Science.gov (United States)

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

    2014-02-01

    We sought to examine whether hospital and provider volumes and cesarean section rates influenced early postpartum invasive methicillin-resistant Staphylococcus aureus (MRSA) infection. We used data from the Nationwide Inpatient Sample, a representative sample of US community hospitals. Multivariate hierarchical regression models were used to estimate odds ratios adjusted for hospital total discharges, nurse:patient ratio, urbanicity, teaching status, bed size, ownership, and geographic region and patient age, race, expected payer, and comorbidities. The total sample size for the hospital analysis was 3,487,350 deliveries, which included 555 cases of MRSA infection. The total sample size for the provider analysis was 1,186,703 deliveries, with 221 cases of MRSA infection. Hospital and provider patient (deliveries) volumes and cesarean section rates were not associated with early postpartum invasive MRSA infection. Barring major bias in our estimates, our results suggest that transmission from providers may not be a predominant route of postpartum MRSA infection in US hospitals. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  11. Socioeconomic Factors Explain Racial Disparities in Invasive Community-Associated Methicillin-Resistant Staphylococcus aureus Disease Rates.

    Science.gov (United States)

    See, Isaac; Wesson, Paul; Gualandi, Nicole; Dumyati, Ghinwa; Harrison, Lee H; Lesher, Lindsey; Nadle, Joelle; Petit, Susan; Reisenauer, Claire; Schaffner, William; Tunali, Amy; Mu, Yi; Ahern, Jennifer

    2017-03-01

    Invasive community-associated methicillin-resistant Staphylococcus aureus (MRSA) incidence in the United States is higher among black persons than white persons. We explored the extent to which socioeconomic factors might explain this racial disparity. A retrospective cohort was based on the Centers for Disease Control and Prevention's Emerging Infections Program surveillance data for invasive community-associated MRSA cases (isolated from a normally sterile site of an outpatient or on hospital admission day ≤3 in a patient without specified major healthcare exposures) from 2009 to 2011 in 33 counties of 9 states. We used generalized estimating equations to determine census tract-level factors associated with differences in MRSA incidence and inverse odds ratio-weighted mediation analysis to determine the proportion of racial disparity mediated by socioeconomic factors. Annual invasive community-associated MRSA incidence was 4.59 per 100000 among whites and 7.60 per 100000 among blacks (rate ratio [RR], 1.66; 95% confidence interval [CI], 1.52-1.80). In the mediation analysis, after accounting for census tract-level measures of federally designated medically underserved areas, education, income, housing value, and rural status, 91% of the original racial disparity was explained; no significant association of black race with community-associated MRSA remained (RR, 1.05; 95% CI, .92-1.20). The racial disparity in invasive community-associated MRSA rates was largely explained by socioeconomic factors. The specific factors that underlie the association between census tract-level socioeconomic measures and MRSA incidence, which may include modifiable social (eg, poverty, crowding) and biological factors (not explored in this analysis), should be elucidated to define strategies for reducing racial disparities in community-associated MRSA rates.

  12. Necrotizing fasciitis caused by Staphylococcus aureus.

    Science.gov (United States)

    Regev, A; Weinberger, M; Fishman, M; Samra, Z; Pitlik, S D

    1998-02-01

    Two patients with rapidly progressive necrotizing fasciitis of a lower extremity due to Staphylococcus aureus as a single pathogen are described. In both patients the portal of entry was attributed to needle puncture (intra-articular injection and intravenous catheter, respectively), followed by bacteremia. Necrotizing fasciitis occurred in a site remote from the needle puncture, suggesting metastatic infection. One patient developed toxic shock syndrome and the other a sunburn-like rash and erythematous mucosae with strawberry tongue. One patient died, and the other required above-knee amputation due to secondary infectious complications. Staphylococcus aureus may mimic the presentation of invasive group A streptococcal infections. A history of needle puncture should alert the physician to the possibility of Staphylococcus aureus infection.

  13. 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

    OpenAIRE

    Yonezawa, Ryuta; Kuwana, Tsukasa; Kawamura, Kengo; Inamo, Yasuji

    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...

  14. Binary typing of staphylococcus aureus

    NARCIS (Netherlands)

    W.B. van Leeuwen (Willem)

    2002-01-01

    textabstractThis thesis describes the development. application and validation of straindifferentiating DNA probes for the characterization of Staphylococcus aureus strains in a system. that yields a binary output. By comparing the differential hybridization of these DNA probes to staphylococcal

  15. Whole-Genome Sequencing for Routine Pathogen Surveillance in Public Health: a Population Snapshot of Invasive Staphylococcus aureus in Europe

    Directory of Open Access Journals (Sweden)

    David M. Aanensen

    2016-05-01

    Full Text Available The implementation of routine whole-genome sequencing (WGS promises to transform our ability to monitor the emergence and spread of bacterial pathogens. Here we combined WGS data from 308 invasive Staphylococcus aureus isolates corresponding to a pan-European population snapshot, with epidemiological and resistance data. Geospatial visualization of the data is made possible by a generic software tool designed for public health purposes that is available at the project URL (http://www.microreact.org/project/EkUvg9uY?tt=rc. Our analysis demonstrates that high-risk clones can be identified on the basis of population level properties such as clonal relatedness, abundance, and spatial structuring and by inferring virulence and resistance properties on the basis of gene content. We also show that in silico predictions of antibiotic resistance profiles are at least as reliable as phenotypic testing. We argue that this work provides a comprehensive road map illustrating the three vital components for future molecular epidemiological surveillance: (i large-scale structured surveys, (ii WGS, and (iii community-oriented database infrastructure and analysis tools.

  16. Evaluation of non-invasive biological samples to monitor Staphylococcus aureus colonization in great apes and lemurs.

    Directory of Open Access Journals (Sweden)

    Frieder Schaumburg

    Full Text Available Reintroduction of endangered animals as part of conservational programs bears the risk of importing human pathogens from the sanctuary to the natural habitat. One bacterial pathogen that serves as a model organism to analyze this transmission is Staphylococcus aureus as it can colonize and infect both humans and animals. The aim of this study was to evaluate the utility of various biological samples to monitor S. aureus colonization in great apes and lemurs.Mucosal swabs from wild lemurs (n=25, Kirindy, Madagascar, feces, oral and genital swabs from captive chimpanzees (n=58, Ngamba and Entebbe, Uganda and fruit wadges and feces from wild chimpanzees (n=21, Taï National Parc, Côte d'Ivoire were screened for S. aureus. Antimicrobial resistance and selected virulence factors were tested for each isolate. Sequence based genotyping (spa typing, multilocus sequence typing was applied to assess the population structure of S. aureus.Oro-pharyngeal carriage of S. aureus was high in lemurs (72%, n=18 and captive chimpanzees (69.2%, n=27 and 100%, n=6, respectively. Wild chimpanzees shed S. aureus through feces (43.8, n=7 and fruit wadges (54.5, n=12. Analysis of multiple sampling revealed that two samples are sufficient to detect those animals which shed S. aureus through feces or fruit wadges. Genotyping showed that captive animals are more frequently colonized with human-associated S. aureus lineages.Oro-pharyngeal swabs are useful to screen for S. aureus colonization in apes and lemurs before reintroduction. Duplicates of stool and fruit wadges reliably detect S. aureus shedding in wild chimpanzees. We propose to apply these sampling strategies in future reintroduction programs to screen for S. aureus colonization. They may also be useful to monitor S. aureus in wild populations.

  17. Staphylococcus aureus Bacteraemia

    Directory of Open Access Journals (Sweden)

    James Price

    2010-01-01

    Full Text Available Staphylococcus aureus bacteraemia (SAB is commonly complicated by metastatic infection or relapse after treatment. Objectives. The study aim was to determine the role of bacterial, host, and management factors in development of complicated SAB. Methods. A prospectively-conducted observational study gathered data on predisposition, management and outcome of 100 consecutive SAB cases. Antibiotic susceptibilities and genetic lineage of bacterial isolates were determined. Further clinical and microbiological data were gathered on two retrospective series from 1999–2000 (n=57 and 2004 (n=116. Results. In the prospective cases, 27% met our definition of complicated disease. Expressed as RR and 95% CI, complicated disease was associated with diabetes (1.58, 1.00–2.48, injecting-drug use (5.48, 0.88–33.49, community-onset of symptoms (1.4, 1.02–1.92, and symptom duration ≥48 hours prior to starting effective antibiotic therapy (2.10, 1.22–3.61. Uncomplicated disease was associated with the presence of a central line (0.69, 0.55–0.88 and prompt removal of a primary focus (0.71, 0.57–0.90. Neither methicillin resistance nor genetic lineage was associated with complicated disease, but methicillin resistance was associated with higher mortality. Conclusions. This study demonstrates that clinical rather than microbial factors are the major determinants of SAB outcome and underscores the importance of early treatment.

  18. Beta-lactam Resistance and Novel Therapeutics for Staphylococcus aureus

    OpenAIRE

    Chan, Liana

    2014-01-01

    Abstractβ-Lactam Resistance and Novel Therapeutics for Staphylococcus aureus byLiana Celene ChanDoctor of Philosophy in Infectious Diseases & ImmunityUniversity of California, BerkeleyProfessor George Sensabaugh, Chair Staphylococcus aureus is an important human pathogen capable of causing disease in otherwise healthy individuals. It causes mostly skin and soft tissue infections but can cause more invasive diseases. Treatment for S. aureus has become a problem due to increasing resistanc...

  19. Improving Diagnosis and Treatment of Staphylococcus aureus Infections : Experimental Studies

    NARCIS (Netherlands)

    S. van den Berg (Sanne)

    2015-01-01

    markdownabstract__Abstract__ Staphylococcus aureus is an opportunistic pathogen that causes a variety of infections, ranging from mild skin infections like furuncles and impetigo, to severe, lifethreatening infections including endocarditis, osteomyelitis and pneumonia. Invasive infections are

  20. Antibiotic susceptibility of Staphylococcus aureus in suppurative ...

    African Journals Online (AJOL)

    1299, p<0.05) and Methicillin resistance was confirmed by PCR. Conclusion: Staphylococcus aureus is highly prevalent and more resistant in inpatients. There is a higher risk of acquiring drug resistant staphylococcus aureus infection in ...

  1. Methicillin-resistant Staphylococcus aureus (MRSA)

    Science.gov (United States)

    Methicillin-resistant Staphylococcus aureus; Hospital-acquired MRSA (HA-MRSA); Staph - MRSA; Staphylococcal - MRSA ... Centers for Disease Control and Prevention website. Methicillin-resistant Staphylococcus aureus (MRSA). www.cdc.gov/mrsa/index.html . Updated ...

  2. Antimicrobial resistant coagulase positive Staphylococcus aureus ...

    African Journals Online (AJOL)

    ADEYEYE

    Isolates of coagulase positive S. aureus resistance to 10 antimicrobials was determined by disc diffusion method. Staphylococcus .... Table 1: Antimicrobial resistance of coagulase positive Staphylococcus. aureus isolates from chickens in Maiduguri,. Nigeria. Antimicrobials .... on Danish poultry and pig farms. Preventive.

  3. Stress Responses in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Frees, Dorte; Ingmer, Hanne

    2016-01-01

    Staphylococcus aures are prominent members of the normal flora of humans and animals, but are also a major cause of mild and severe infections. To persist and disseminate in the human host, and to survive in environmental settings, such as hospitals, S. aureus have developed a plethora of cellular...

  4. Effects of vitamin D and its metabolites on cell viability and Staphylococcus aureus invasion into bovine mammary epithelial cells.

    Science.gov (United States)

    Yue, Yuan; Hymøller, Lone; Jensen, Søren K; Lauridsen, Charlotte; Purup, Stig

    2017-05-01

    Vitamin D has been found have various biological effects that may be potent in preventing bovine mastitis. Two forms of vitamin D, vitamin D 2 (D 2 ) and vitamin D 3 (D 3 ), can be hydroxylated to functional metabolites in cattle. The objectives of the present study were to investigate the potential of vitamin D compounds for controlling bovine mastitis using in vitro cell models, and to compare the differences between D 2 and D 3 compounds. Results showed that D 2 compounds have comparable effects to their D 3 analogues on inhibiting MAC-T cell viability in vitro. S. aureus growth was inhibited by high concentrations of D 2 , D 3 , 25(OH)D 2 and 25(OH)D 3 . 25(OH)D 2 and 25(OH)D 3 induced CYP24A1 expression but reduced VDR mRNA expression, whereas the expression of CYP27B1, occludin, and E-cadherin did not change. Additionally, the induction of CYP24A1 expression by 25(OH)D 3 was higher than that of 25(OH)D 2 , which may contribute to their differences in inhibiting cell viability. S. aureus invaded into MAC-T cells and universally inhibited gene expressions. Pre-treat MAC-T cells with 25(OH)D 2 reduced S. aureus adhesion while pre-treatment with 25(OH)D 3 inhibited S. aureus invasion, but neither of the compounds attenuated the S. aureus-induced gene expression reduction. In conclusion, the present study shows that D 2 compounds have comparable effects on inhibiting cell viability and S. aureus invasion to their D 3 analogues in vitro, suggesting that D 2 and its metabolites have potential in controlling bovine mastitis. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Mammary Gland Pathology Subsequent to Acute Infection with Strong versus Weak Biofilm Forming Staphylococcus aureus Bovine Mastitis Isolates: A Pilot Study Using Non-Invasive Mouse Mastitis Model.

    Science.gov (United States)

    Gogoi-Tiwari, Jully; Williams, Vincent; Waryah, Charlene Babra; Costantino, Paul; Al-Salami, Hani; Mathavan, Sangeetha; Wells, Kelsi; Tiwari, Harish Kumar; Hegde, Nagendra; Isloor, Shrikrishna; Al-Sallami, Hesham; Mukkur, Trilochan

    2017-01-01

    Biofilm formation by Staphylococcus aureus is an important virulence attribute because of its potential to induce persistent antibiotic resistance, retard phagocytosis and either attenuate or promote inflammation, depending upon the disease syndrome, in vivo. This study was undertaken to evaluate the potential significance of strength of biofilm formation by clinical bovine mastitis-associated S. aureus in mammary tissue damage by using a mouse mastitis model. Two S. aureus strains of the same capsular phenotype with different biofilm forming strengths were used to non-invasively infect mammary glands of lactating mice. Biofilm forming potential of these strains were determined by tissue culture plate method, ica typing and virulence gene profile per detection by PCR. Delivery of the infectious dose of S. aureus was directly through the teat lactiferous duct without invasive scraping of the teat surface. Both bacteriological and histological methods were used for analysis of mammary gland pathology of mice post-infection. Histopathological analysis of the infected mammary glands revealed that mice inoculated with the strong biofilm forming S. aureus strain produced marked acute mastitic lesions, showing profuse infiltration predominantly with neutrophils, with evidence of necrosis in the affected mammary glands. In contrast, the damage was significantly less severe in mammary glands of mice infected with the weak biofilm-forming S. aureus strain. Although both IL-1β and TNF-α inflammatory biomarkers were produced in infected mice, level of TNF-α produced was significantly higher (pmastitis model, and offers an opportunity for the development of novel strategies for reduction of mammary tissue damage, with or without use of antimicrobials and/or anti-inflammatory compounds for the treatment of bovine mastitis.

  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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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.

    Science.gov (United States)

    Yonezawa, Ryuta; Kuwana, Tsukasa; Kawamura, Kengo; Inamo, Yasuji

    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 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.

  8. The Novel Transcriptional Regulator SA1804 Is Involved in Mediating the Invasion and Cytotoxicity of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    JUNSHU eYANG

    2015-03-01

    Full Text Available The two-component regulatory system, SaeRS, controls expression of important virulence factors, including toxins and invasins, which contribute to the pathogenicity of Staphylococcus aureus. Previously, we conducted a transcriptomics study for identification of SaeRS regulon and found that inactivation of SaeRS dramatically enhances the transcription of a novel transcriptional regulator (SA1804. This led us to question whether SA1804 is involved in bacterial pathogenicity by regulating the expression of virulence factors. To address this question, we created sa1804, saeRS, and sa1804/saeRS double deletion mutants in a USA300 community-acquired MRSA strain, 923, and determined their impact on the pathogenicity. The deletion of sa1804 dramatically increased the cytotoxicity and enhanced the capacity of bacteria to invade into the epithelial cells (A549, whereas the deletion of saeRS eliminated the cytotoxicity and abolished the bacterial ability to invade into the epithelial cells. Moreover, the double deletions of sa1804 and saeRS appeared a similar phenotype with the saeRS null mutation. Furthermore, we determined the regulatory mechanism of SA1804 using qPCR and gel-shift approaches. Our data indicate that the novel virulence repressor SA1804 is dependent on the regulation of SaeRS. This study sheds light on the regulatory mechanism of virulence factors and allows for us further elucidate the molecular pathogenesis of S. aureus.

  9. Susceptibility trends including emergence of linezolid resistance among coagulase-negative staphylococci and meticillin-resistant Staphylococcus aureus from invasive infections.

    Science.gov (United States)

    Decousser, Jean-Winoc; Desroches, Marine; Bourgeois-Nicolaos, Nadège; Potier, Julien; Jehl, François; Lina, Gérard; Cattoir, Vincent; Vandenesh, François; Doucet-Populaire, Florence

    2015-12-01

    Multiresistance in staphylococci constitutes a major challenge for the antimicrobial chemotherapy of invasive infections such as bacteraemia or bone and joint infections (BJIs). A nationwide prospective study was performed to detect antimicrobial resistance trends among staphylococci causing invasive infections. Between October 2011 and February 2012, 367 meticillin-resistant Staphylococcus aureus (MRSA) and 695 coagulase-negative staphylococci (CoNS) were collected from 37 French hospitals, mainly from bacteraemia (59.9%) and osteoarticular infections (29.0%). Minimum inhibitory concentrations (MICs) were determined by broth microdilution, and specific screening and confirmation tests were performed to detect heterogeneous vancomycin-intermediate S. aureus (hVISA). Staphylococcal isolates exhibiting a linezolid MIC>4 mg/L were further characterised to determinate their clonal relationships and the mechanism of resistance. MRSA exhibited additional resistances, including levofloxacin (82% associated resistance), gentamicin (13.6%), fusidic acid (13.6%) and rifampicin (6.5%), compromising oral step-down therapy in BJIs. Only two hVISA strains (0.5%) were identified. Among the CoNS, mainly Staphylococcus epidermidis (506/695; 72.8%), resistance to first- and second-line agents was more common. Linezolid resistance was identified in 10 CoNS (1.4%). The most frequent linezolid resistance mechanism was the G2576T mutation in 23S rDNA (9/10). For the first time in France, the cfr gene was found in five related sequence type 2 (ST2) S. epidermidis from two different hospitals, in association with ribosomal RNA and L3 ribosomal protein mutations. These national data must be considered when selecting empirical treatment for invasive staphylococcal infections. Moreover, the emergence and spread of linezolid-resistant CoNS carrying the cfr gene is of concern. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  10. Nasal carriage of Meticillin resistance Staphylococcus aureus ...

    African Journals Online (AJOL)

    Gemeda

    BACKGROUND: Staphylococcus aureus is one of the major causes of community and hospital acquired infections. The emergence of methicillin resistant strains of. Staphylococcus aureus in the hospitals and the community is a serious health problem. The aim of this study was to determine the nasal carriage and ...

  11. Nasal Carriage of Methicillin Resistant Staphylococcus aureus ...

    African Journals Online (AJOL)

    BACKGROUND: Staphylococcus aureus is one of the major causes of community and hospital acquired infections. The emergence of methicillin resistant strains of Staphylococcus aureus in the hospitals and the community is a serious health problem. The aim of this study was to determine the nasal carriage and ...

  12. METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS (MRSA ...

    African Journals Online (AJOL)

    Nosocomial infections caused by methicillin-resistant strains of Staphylococcus aureus often pose therapeutic dilemma to the clinicians because of the multi resistant nature of these strains of Staphylococcus aureus. Outbreaks of both nosocomial and community acquired infections are also frequent and difficult to control.

  13. Transmission of Staphylococcus aureus between mothers and infants in an African setting

    NARCIS (Netherlands)

    Schaumburg, F.; Alabi, A. S.; Mombo-Ngoma, G.; Kaba, H.; Zoleko, R. M.; Diop, D. A.; Mackanga, J.-R.; Basra, A.; Gonzalez, R.; Menendez, C.; Grobusch, M. P.; Kremsner, P. G.; Köck, R.; Peters, G.; Ramharter, M.; Becker, K.

    2014-01-01

    Staphylococcus aureus colonization is a risk factor for invasive disease. There is a need to understand S. aureus colonization in infancy as the burden of S. aureus infections in infants is high. We aimed to investigate the transmission of S. aureus between mothers and their newborns during the

  14. A Caenorhabditis elegans Host Model Correlates with Invasive Disease Caused by Staphylococcus aureus Recovered during an Outbreak in Neonatal Intensive Care

    Directory of Open Access Journals (Sweden)

    Kaiyu Wu

    2012-01-01

    Full Text Available BACKGROUND: Caenorhabditis elegans has previously been used as a host model to determine the virulence of clinical methicillin-resistant Staphylococcus aureus isolates. In the present study, methicillin-susceptible S aureus (MSSA strains associated with an outbreak in a neonatal intensive care unit (NICU were investigated using the C elegans model.

  15. Distribution of the serine-aspartate repeat protein-encoding sdr genes among nasal-carriage and invasive Staphylococcus aureus strains.

    NARCIS (Netherlands)

    Sabat, Artur; Melles, Damian C; Martirosian, Gayane; Grundmann, Hajo; Belkum, Alex van; Hryniewicz, Waleria

    2006-01-01

    The sdr locus was found in all 497 investigated Staphylococcus aureus strains, although in 29 strains it contained only the sdrC gene (sdrD negative, sdrE negative). The sdrC-positive, sdrD-negative, sdrE-negative gene profile was exclusive to methicillin-sensitive S. aureus (MSSA) strains (Fisher's

  16. Staphylococcus aureus and hand eczema severity

    DEFF Research Database (Denmark)

    Haslund, P; Bangsgaard, N; Jarløv, J O

    2009-01-01

    BACKGROUND: The role of bacterial infections in hand eczema (HE) remains to be assessed. OBJECTIVES: To determine the prevalence of Staphylococcus aureus in patients with HE compared with controls, and to relate presence of S. aureus, subtypes and toxin production to severity of HE. METHODS......: Bacterial swabs were taken at three different visits from the hand and nose in 50 patients with HE and 50 controls. Staphylococcus aureus was subtyped by spa typing and assigned to clonal complexes (CCs), and isolates were tested for exotoxin-producing S. aureus strains. The Hand Eczema Severity Index...... was used for severity assessment. RESULTS: Staphylococcus aureus was found on the hands in 24 patients with HE and four controls (P aureus was found to be related to increased severity of the eczema (P aureus types on the hands...

  17. Staphylococcus aureus transmission : clinical and molecular aspects

    NARCIS (Netherlands)

    Bloemendaal, A.L.A.

    2010-01-01

    Staphylococcus aureus is a major pathogen in nosocomial infections. Up to 30% of UCI related infections are caused by S. aureus. In this thesis we explore both clinical and molecular aspects of patient-to-patient transmission of S. aureus. We performed a European ICU study exploring infection

  18. Vancomycin Sensitivity of Staphylococcus aureus isolates from ...

    African Journals Online (AJOL)

    Methicillin-resistant Staphylococcus aureus (S. aureus) (MRSA), resistant to all antibiotics including Vancomycin, has been reported in Japan, USA, Canada and Brazil. Hence, the main objective of this study was to evaluate the possible presence of Vancomycin resistant or intermediate S.aureus in Karachi. A total of 850 ...

  19. Prevalence of methicillin resistant Staphylococcus aureus and ...

    African Journals Online (AJOL)

    Staphylococcus aureus is the leading overall cause otf nosocomial infections with increasing resistance to β lactam antibiotics. This study was carried out to study the current resistant/susceptibility pattern of S. aureus to β lactam antibiotics and prevalence of Methicillin Resistant S. aureus (MRSA) in the studied population.

  20. Exfoliative Toxins of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michal Bukowski

    2010-05-01

    Full Text Available Staphylococcus aureus is an important pathogen of humans and livestock. It causes a diverse array of diseases, ranging from relatively harmless localized skin infections to life-threatening systemic conditions. Among multiple virulence factors, staphylococci secrete several exotoxins directly associated with particular disease symptoms. These include toxic shock syndrome toxin 1 (TSST-1, enterotoxins, and exfoliative toxins (ETs. The latter are particularly interesting as the sole agents responsible for staphylococcal scalded skin syndrome (SSSS, a disease predominantly affecting infants and characterized by the loss of superficial skin layers, dehydration, and secondary infections. The molecular basis of the clinical symptoms of SSSS is well understood. ETs are serine proteases with high substrate specificity, which selectively recognize and hydrolyze desmosomal proteins in the skin. The fascinating road leading to the discovery of ETs as the agents responsible for SSSS and the characterization of the molecular mechanism of their action, including recent advances in the field, are reviewed in this article.

  1. [Staphylococcus aureus and antibiotic resistance].

    Science.gov (United States)

    Sancak, Banu

    2011-07-01

    After the report of first case of methicillin-resistant Staphylococcus aureus (MRSA) in 1961, MRSA become a major problem worldwide. Over the last decade MRSA strains have emerged as serious pathogens in nosocomial and community settings. Glycopeptides (vancomycin and teicoplanin) are still the current mainstay of therapy for infections caused by MRSA. In the last decade dramatic changes have occurred in the epidemiology of MRSA infections. The isolates with reduced susceptibility and in vitro resistance to vancomycin have emerged. Recently, therapeutic alternatives such as quinupristin/dalfopristin, linezolid, tigecycline and daptomycin have been introduced into clinical practice for treating MRSA infections. Nevertheless, these drugs are only approved for certain indication and resistance has already been reported. In this review, the new information on novel drugs for treating MRSA infections and the resistance mechanisms of these drugs were discussed.

  2. Prevalence and resistance of commensal Staphylococcus aureus, including meticillin-resistant Staphylococcus aureus: a European cross-sectional study.

    NARCIS (Netherlands)

    Heijer, C.D.J. den; Bijnen, E.M.E. van; Paget, W.J.; Pringle, M.; Goossen, H.; Bruggeman, C.A.; Schellevis, F.G.; Stobberingh, E.E.

    2014-01-01

    Background: Information on the prevalence of Staphylococcus aureus resistance has mainly been obtained from invasive strains, although the commensal flora is considered an important reservoir of resistance. Within ‘The Appropriateness of prescribing antibiotics in primary health care in Europe with

  3. Immunopathogenesis of Staphylococcus aureus pulmonary infection

    Science.gov (United States)

    Parker, Dane; Prince, Alice

    2013-01-01

    Staphylococcus aureus is a common human pathogen highly evolved as both a component of the commensal flora and as a major cause of invasive infection. Severe respiratory infection due to staphylococci has been increasing due to the prevalence of more virulent USA300 CA-MRSA strains in the general population. The ability of S. aureus to adapt to the milieu of the respiratory tract has facilitated its emergence as a respiratory pathogen. Its metabolic versatility, the ability to scavenge iron, coordinate gene expression, and the horizontal acquisition of useful genetic elements have all contributed to its success as a component of the respiratory flora, in hospitalized patients, as a complication of influenza and in normal hosts. The expression of surface adhesins facilitates its persistence in the airways. In addition, the highly sophisticated interactions of the multiple S. aureus virulence factors, particularly the α-hemolysin and protein A, with diverse immune effectors in the lung such as ADAM10, TNFR1, EGFR, immunoglobulin, and complement all contribute to the pathogenesis of staphylococcal pneumonia. PMID:22037948

  4. Staphylococcus aureus resistente a vancomicina.

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Rodríguez

    2005-12-01

    Full Text Available Objetivo. Revisar la evolución y mecanismos moleculares de la resistencia de Staphylococcus aureus a vancomicina. Fuente de los datos. Se consultó la base de datos MEDLINE y se seleccionaron artículos tipo reportes de caso, estudios bioquímicos, de microscopía electrónica y biología molecular pertinentes. Síntesis. Después de casi 40 años de eficacia ininterrumpida de la vancomicina, en 1997 se reportaron los primeros casos de fracaso terapéutico debido a cepas de Staphylococcus aureus con resistencia intermedia, denominadas VISA (concentración inhibitoria mínima, CIM, 8 a 16 ?g/ml, así como a cepas con resistencia heterogénea hVISA (CIM global = 4 ?g/ml, pero con subpoblaciones VISA, en las cuales la resistencia está mediada por engrosamiento de la pared celular y disminución de su entrecruzamiento, lo que afecta la llegada del antibiótico al blanco principal, los monómeros del peptidoglicano en la membrana plasmática. En 2002 se aisló la primera de las 3 cepas reportadas hasta la fecha con resistencia total al antibiótico, denominadas VRSA (CIM>32 ?g/ml, en las que se encontró el transposón Tn1546 proveniente de Enterococcus spp, responsable del reemplazo de la terminación D-Ala-D-Ala por D-Ala-Dlactato en los precursores de la pared celular con pérdida de la afinidad por el glicopéptido. Conclusiones. La resistencia a vancomicina es una realidad en S. aureus, mediada en el caso de VISA por alteraciones en la pared celular que atrapan el antibiótico antes de llegar al sitio de acción, y en el caso de VRSA, por transferencia desde Enterococcus spp. de genes que llevan a la modificación del blanco molecular.

  5. Comparative Efficacy of Ceftaroline with Linezolid against Staphylococcus aureus and Methicillin Resistant Staphylococcus aureus.

    Science.gov (United States)

    Hafeez, Amira; Munir, Tehmina; Rehman, Sabahat; Najeeb, Sara; Gilani, Mehreen; Latif, Mahwish; Ansari, Maliha; Saad, Nadia

    2015-04-01

    To compare the in vitro antimicrobial efficacy of ceftaroline with linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. Quasi-experimental study. Microbiology Department, Army Medical College, Rawalpindi, from January to December 2013. 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 (30 μg) and the isolates were considered methicillin resistant if the zone of inhibition around cefoxitin disc was ≤ 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 °C aerobically for 18 - 24 hours. Diameters of inhibition zone were measured and interpretated as per Clinical and Laboratory Standards Institute (CLSI) guidelines. 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. Ceftaroline is equally effective as linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus.

  6. Population structure of Staphylococcus aureus in China

    NARCIS (Netherlands)

    Yan, Xiaomei

    2015-01-01

    The present PhD research was aimed at analysing the population structure of Staphylococcus aureus in China. Between 2000 and 2005 we found that patients from a single Chinese hospital showed increasing trends in antimicrobial resistance. Among methicillin-resistant S. aureus (MRSA), resistance

  7. Immunogenicity of toxins during Staphylococcus aureus infection

    NARCIS (Netherlands)

    N.J. Verkaik (Nelianne); O. Dauwalder (Olivier); K. Antri (Kenza); I. Boubekri (Ilhem); C.P. de Vogel (Corné); C. Badiou (Cédric); M. Bes (Michèle); F. Vandenesch (François); M. Tazir (Mohammed); H. Hooijkaas (Herbert); H.A. Verbrugh (Henri); A.F. van Belkum (Alex); J. Etienne (Jerome); G. Lina (Gérard); N. Ramdani-Bouguessa (Nadjia); W.J.B. van Wamel (Willem)

    2010-01-01

    textabstractAB - BACKGROUND: Toxins are important Staphylococcus aureus virulence factors, but little is known about their immunogenicity during infection. Here, additional insight is generated. METHODS: Serum samples from 206 S. aureus-infected patients and 201 hospital-admitted control subjects

  8. Staphylococcus aureus transmission : clinical and molecular aspects

    OpenAIRE

    Bloemendaal, A.L.A.

    2010-01-01

    Staphylococcus aureus is a major pathogen in nosocomial infections. Up to 30% of UCI related infections are caused by S. aureus. In this thesis we explore both clinical and molecular aspects of patient-to-patient transmission of S. aureus. We performed a European ICU study exploring infection prevention measures and their influence on transmission. We developed a experimental transmission model in animals, showing a difference in spread and colonization persistence between MSSA and MRSA. Next...

  9. Population structure of Staphylococcus aureus in China

    OpenAIRE

    Yan, Xiaomei

    2015-01-01

    The present PhD research was aimed at analysing the population structure of Staphylococcus aureus in China. Between 2000 and 2005 we found that patients from a single Chinese hospital showed increasing trends in antimicrobial resistance. Among methicillin-resistant S. aureus (MRSA), resistance against rifampicin doubled to 68%. Staphylococcal food poisoning (SFP) is frequent in China. Two predominant S. aureus lineages, ST6 and ST943, were identified causing outbreaks of SFP in Southern China...

  10. 9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Staphylococcus Aureus Bacterin-Toxoid... REQUIREMENTS Inactivated Bacterial Products § 113.115 Staphylococcus Aureus Bacterin-Toxoid. Staphylococcus... Staphylococcus aureus which has been inactivated and is nontoxic. Each serial of biological product containing...

  11. An uncommon presentation for a severe invasive infection due to methicillin-resistant Staphylococcus aureus clone USA300 in Italy: a case report

    Directory of Open Access Journals (Sweden)

    Tronci Mirella

    2008-04-01

    Full Text Available Abstract Background Methicillin resistant Staphylococcus aureus (MRSA has been considered for many years a typical nosocomial pathogen. Recently MRSA has emerged as a frequent cause of infections in the community. More commonly, community-acquired (CA-MRSA is a cause of infections of the skin and soft-tissues, but life-threatening infections such as necrotizing pneumonia and sepsis can occasionally occur. Case presentation This report describes an uncommon presentation of invasive CA-MRSA infection in an adolescent without known risk factors. The presentation was typical for bacterial meningitis, but the clinical findings also revealed necrotizing pneumonia. Following the development of deep venous thrombosis, the presence of an inherited trombophilic defect (factor V Leiden was detected. The patient was successfully treated with an antibiotic combination including linezolid and with anticoagulant therapy. CA-MRSA was isolated from both cerebrospinal fluid and blood. The isolates were resistant to oxacillin and other beta-lactam antibiotics and susceptible to the other antibiotics tested including erythromycin. Molecular typing revealed that the strains contained the Panton-Valentine leukocidin genes and type IV SCCmec, and were ST8, spa type t008, and agr type 1. This genetic background is identical to that of the USA300 clone. Conclusion This report highlights that meningitis can be a new serious presentation of CA-MRSA infection. CA-MRSA strains with the genetic background of the USA300 clone are circulating in Italy and are able to cause severe infections.

  12. Transfer of Antibiotic Resistance in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Haaber, Jakob; Penadés, José R; Ingmer, Hanne

    2017-01-01

    Staphylococcus aureus is a serious human pathogen with remarkable adaptive powers. Antibiotic-resistant clones rapidly emerge mainly by acquisition of antibiotic-resistance genes from other S. aureus strains or even from other genera. Transfer is mediated by a diverse complement of mobile genetic...... of plasmids that can be transferred by conjugation and the efficiency with which transduction occurs. Here, we review the main routes of antibiotic resistance gene transfer in S. aureus in the context of its biology as a human commensal and a life-threatening pathogen. Staphylococcus aureus cells...... are effective in exchanging mobile genetic elements, including antibiotic-resistance genes.During colonization or infection of host organisms, the exchange appears to be particularly effective.Bacteriophage-mediated transfer involves both transduction and autotransduction, which may enable lysogenic S. aureus...

  13. Distribution of the serine-aspartate repeat protein-encoding sdr genes among nasal-carriage and invasive Staphylococcus aureus strains.

    OpenAIRE

    Sabat, Artur; Melles, Damian C; Martirosian, Gayane; Grundmann, Hajo; Belkum, Alex van; Hryniewicz, Waleria

    2006-01-01

    The sdr locus was found in all 497 investigated Staphylococcus aureus strains, although in 29 strains it contained only the sdrC gene (sdrD negative, sdrE negative). The sdrC-positive, sdrD-negative, sdrE-negative gene profile was exclusive to methicillin-sensitive S. aureus (MSSA) strains (Fisher's exact test; P = 0.0005) and was not found in the strains collected from bone infections (P = 0.0019). We also found a strong association between the presence of the sdrD gene and methicillin-resis...

  14. Community-associated Staphylococcus aureus infections: pneumonia

    OpenAIRE

    Marios Karvouniaris; Demosthenes Makris; Epaminondas Zakynthinos

    2010-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emerging health problem with distinct epidemiology. CA-MRSA colonization and infection is associated with risk factors different from healthcare-associated methicillin-resistant S. aureus infection. CA-MRSA strains pre­sent different characteristics to healthcare associated strains in terms of microbiology as well. Moreover, infection as a result of CA-MRSA may be associated with severe infections, in particular ...

  15. Distribution of the serine-aspartate repeat protein-encoding sdr genes among nasal-carriage and invasive Staphylococcus aureus strains.

    Science.gov (United States)

    Sabat, Artur; Melles, Damian C; Martirosian, Gayane; Grundmann, Hajo; van Belkum, Alex; Hryniewicz, Waleria

    2006-03-01

    The sdr locus was found in all 497 investigated Staphylococcus aureus strains, although in 29 strains it contained only the sdrC gene (sdrD negative, sdrE negative). The sdrC-positive, sdrD-negative, sdrE-negative gene profile was exclusive to methicillin-sensitive S. aureus (MSSA) strains (Fisher's exact test; P = 0.0005) and was not found in the strains collected from bone infections (P = 0.0019). We also found a strong association between the presence of the sdrD gene and methicillin-resistant S. aureus strains (P < 0.0001). Our findings suggest that MSSA strains with the newly uncovered sdrC-positive, sdrD-negative, sdrE-negative gene profile have a substantially decreased potential to establish bone infection.

  16. Characterisation of Staphylococcus aureus bacteraemia at Tygerberg hospital

    NARCIS (Netherlands)

    Orth, H.; Dreyer, Z.S.; Makgotlho, E.; Oosthuysen, W.; Sinha, B.; Wasserman, E.

    2013-01-01

    To elucidate the local epidemiology of Staphylococcus aureus bacteraemia, we characterised blood culture isolates using molecular methods and prospectively collected clinical data to determine the occurrence of community-acquired, methicillinresistant S. aureus (MRSA). Consecutive S. aureus blood

  17. The T Cell Response to Staphylococcus aureus

    Science.gov (United States)

    Bröker, Barbara M.; Mrochen, Daniel; Péton, Vincent

    2016-01-01

    Staphylococcus aureus (S. aureus) is a dangerous pathogen and a leading cause of both nosocomial and community acquired bacterial infection worldwide. However, on the other hand, we are all exposed to this bacterium, often within the first hours of life, and usually manage to establish equilibrium and coexist with it. What does the adaptive immune system contribute toward lifelong control of S. aureus? Will it become possible to raise or enhance protective immune memory by vaccination? While in the past the S. aureus-specific antibody response has dominated this discussion, the research community is now coming to appreciate the role that the cellular arm of adaptive immunity, the T cells, plays. There are numerous T cell subsets, each with differing functions, which together have the ability to orchestrate the immune response to S. aureus and hence to tip the balance between protection and pathology. This review summarizes the state of the art in this dynamic field of research. PMID:26999219

  18. Maternal-neonatal outcome with Staphylococcus aureus rectovaginal colonization.

    Science.gov (United States)

    Ghanim, Nibal; Alchyib, Omrou; Morrish, Donald; Tompkins, David; Julliard, Kell; Visconti, Ernest; Hoskins, Iffath A

    2011-01-01

    To estimate prevalence of rectovaginal colonization by Staphylococcus aureus among pregnant women with group B streptococcus (GBS) screening results and its association with maternal and infant outcomes. Cultures that detected both group B streptococcus (GBS) and S. aureus were obtained at > or = 35 weeks of gestation. Computerized database search and chart review determined invasive neonatal infection and maternal outcomes at the time of delivery through 6 months postpartum. A total of 6,626 GBS screening cultures met study criteria, and 769 (11.6%) GBS isolates and 67 (1.0%) S. aureus were identified. No maternal S. aureus-related outcomes were found. The rate of maternal methicillin-resistant S. aureus colonization was 0.1% (7 in 6,626). GBS-positive patients were twice as likely to be colonized with methicillin-susceptible S. aureus than GBS-negative patients. GBS-positive culture rates differed significantly by primary language: Spanish 10.0%, English 13.7%, Russian 26.9%, Cantonese 13.2%, Mandarin 11.5%, Arabic 15.9%, and other 17.8%. In our population, S. aureus colonization percentage (1.0%) was lower than the 7.5-8.2% reported by other medical centers, as was overall GBS carriage rate. S. aureus did not predispose to maternal or infant morbidity or mortality up to 6 months postpartum.

  19. Antimicrobial resistant coagulase positive Staphylococcus aureus ...

    African Journals Online (AJOL)

    ADEYEYE

    ISSN 2315-6201). Suleiman/Sokoto Journal of Veterinary Sciences (2013). 11(1): 51-55. http://dx.doi.org/10.4314/sokjvs.v11i1.8. Antimicrobial resistant coagulase positive Staphylococcus aureus from chickens in Maiduguri,Nigeria. A Suleiman.

  20. Fibronectin enhances transfection of Staphylococcus aureus.

    OpenAIRE

    Thompson, N E; Bergdoll, M S; Pattee, P A

    1985-01-01

    The factor in normal sera primarily responsible for the enhancement of transfection (and transformation) of Staphylococcus aureus was identified as fibronectin. Serum samples which were depleted of fibronectin by affinity chromatography showed a marked decrease in enhancing activity. Fibronectin isolated from sera of several animal species demonstrated enhancing activity.

  1. METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS (MRSA ...

    African Journals Online (AJOL)

    The methicillin disc diffusion method for the detection of methicillin resistance and the Kirby-Bauer disc diffusion for antibiotic susceptibility tests, were used. The MRSA prevalence rate was 34.7% (51/147) of all Staphylococcus aureus isolates. Forty-five isolates were associated with infections and 6 were colonizing strains.

  2. Meticillineresistente Staphylococcus aureus (MRSA) in de gemeenschap

    NARCIS (Netherlands)

    Vonk, A. G.; Vandenbroucke-Grauls, C. M. J. E.

    2007-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections have been confined to healthcare centres for decades. However, MRSA infections are increasingly seen in young healthy individuals with no exposure to healthcare centres. These community-acquired MRSA (CA-MRSA) strains differ from

  3. Staphylococcus aureus resistente a la meticilina (SARM)

    Centers for Disease Control (CDC) Podcasts

    2007-10-22

    Datos importantes sobre las infecciones por SARM en Estados Unidos, en las escuelas y los entornos médicos. (Title: Methicillin-resistant Staphylococcus aureus (MRSA)Created: 10/2007).  Created: 10/22/2007 by National Center for Preparedness, Detection, and Control of Infectious Diseases.   Date Released: 11/9/2007.

  4. Methicillin-resistant Staphylococcus aureus transmission

    DEFF Research Database (Denmark)

    Andersen, Leif Percival; Nielsen, Xiaohui

    2015-01-01

    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...

  5. Topography of Distinct Staphylococcus aureus Types in Chronic Wounds of Patients with Epidermolysis Bullosa

    NARCIS (Netherlands)

    van der Kooi-Pol, Magdalena M.; Sadaghian Sadabad, Mehdi; Duipmans, Jose C.; Sabat, Artur J.; Stobernack, Tim; Omansen, Till F.; Westerhout-Pluister, Gerlinde N.; Jonkman, Marcel F.; Harmsen, Hermie J. M.; van Dijl, Jan Maarten

    2013-01-01

    The opportunistic pathogen Staphylococcus aureus is known to interfere with wound healing and represents a significant risk factor for wound infections and invasive disease. It is generally assumed that one individual is predominantly colonized by one S. aureus type. Nevertheless, patients with the

  6. ESCHERICHIA COLI AND STAPHYLOCOCCUS AUREUS

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. The bio-effects of the ethanol extracts from the leaf and stem of Momordica charantia were studied with the view to ascertain the medical usefulness ascribed to the plant by the locals. The plant parts, stem and leaf, revealed remarkable activity against Escherichia coli and Staphlococcus aureus. The leaves ...

  7. [Resistance to antibiotics of Staphylococcus aureus responsible of osteoarticular infections].

    Science.gov (United States)

    Raymond, J; Bergeret, M

    2007-10-01

    Osteo-articular infections represent the majority of invasive Staphylococcus aureus infections in children. It is demonstrated that, independently of the resistance or susceptibility to methicillin, the production of Panton-Valentine leukocidin (PVL) by S. aureus enhanced the severity of the disease. However, an increase of the rate of community acquired methicillin-resistant S. aureus (CA-MRSA) has been reported in osteo-articular infections. These CA-MRSA are the most often susceptible to the other antibiotics. SCCmec elements of type IV or V associated with the PVL coding genes seem to be molecular markers of CA-MRSA. The risk factors of acquisition of these strains are the young age of children and the overcrowding. It is now established that CA-MRSA are pathogens present all over the world. It thus became necessary to look after the epidemiology of these virulent strains.

  8. Meticillin-resistant Staphylococcus aureus (MRSA)

    DEFF Research Database (Denmark)

    Stefani, Stefania; Chung, Doo Ryeon; Lindsay, Jodi A

    2012-01-01

    This article reviews recent findings on the global epidemiology of healthcare-acquired/associated (HA), community-acquired/associated (CA) and livestock-associated (LA) meticillin-resistant Staphylococcus aureus (MRSA) and aims to reach a consensus regarding the harmonisation of typing methods...... health. Continuous efforts to understand the changing epidemiology of S. aureus infection in humans and animals are therefore necessary, not only for appropriate antimicrobial treatment and effective infection control but also to monitor the evolution of the species. The group made several consensus...

  9. Nasal carriage of methicillin-resistant Staphylococcus aureus by ...

    African Journals Online (AJOL)

    Strains of Staphylococcus aureus were isolated from the anterior nares of healthy pupils and their antibiotic susceptibility patterns were determined. 116 isolates of Staphylococcus aureus (100%) were biochemically characterized as coagulase positive S. aureus. Susceptibility profile of the isolates revealed that 15(14.85%) ...

  10. The sensitivity status of community-acquired Staphylococcus aureus ...

    African Journals Online (AJOL)

    Community acquired Staphylococcus aureus was isolated from various infectious sites in two private laboratories in Kano-city, Nigeria. A total of 247 (11%) Staphylococcu aureus isolates were recovered from all infectious sites except cerebro-spinal fluid. The least Staphylococcus aureus isolates were found in urine ...

  11. Relationship and susceptibility profile of Staphylococcus aureus infection diabetic foot ulcers with Staphylococcus aureus nasal carriage.

    Science.gov (United States)

    Taha, Aza Bahadeen

    2013-03-01

    Staphylococcus aureus is the main cause of diabetic foot infection with the patient's endogenous flora as the principal source. Nasal carriage of S. aureus has been identified as an important risk factor for the acquisition of diabetic foot infections. The study assessment the associations of S. aureus with methicillin resistant S. aureus were isolation from diabetic foot infection and nasal carriage of the same patients and their antibiotic susceptibility profile. Diagnosis of S. aureus and methicillin resistant S. aureus were carried out by using standard procedures. Antibiotic sensitivity profiles were determent by breakpoint dilution method. Out of 222 S. aureus isolation, 139 (62.61%) were isolated from the diabetic foot and 83 (37.39%) from the nasal carriage. Seventy one (30.87%) of the patients were S. aureus infection diabetic foot with nasal carriage. Among diabetic foot infection and nasal carriage patients, 40.85% of S. aureus were considered as methicillin resistant S. aureus. Rifampicin (96.40%) and Levofloxacin (91.44%) were active against S. aureus. Patients at strong risk for methicillin resistant S. aureus nasal carriage and subsequent diabetic foot infection with high resistance to antibiotics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Staphylococcus lugdunensis, a serious pathogen in periprosthetic joint infections: comparison to Staphylococcus aureus and Staphylococcus epidermidis

    Directory of Open Access Journals (Sweden)

    J. Lourtet-Hascoët

    2016-10-01

    Conclusion: S. lugdunensis is an emerging pathogen with a pathogenicity quite similar to that of S. aureus. This coagulase-negative Staphylococcus must be identified precisely in PJI, in order to select the appropriate surgical treatment and antibiotics .

  13. [Change in drug resistance of Staphylococcus aureus].

    Science.gov (United States)

    Lin, Yan; Liu, Yan; Luo, Yan-Ping; Liu, Chang-Ting

    2013-11-01

    To analyze the change in drug resistance of Staphylococcus aureus (SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications. The SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards (NCCLS) guidelines. SAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillin-resistant Staphylococcus aureus (MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive Staphylococcus aureus (MSSA) (P resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years. Drug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.

  14. Silkworm Apolipophorin Protein Inhibits Staphylococcus aureus Virulence*

    Science.gov (United States)

    Hanada, Yuichi; Sekimizu, Kazuhisa; Kaito, Chikara

    2011-01-01

    Silkworm hemolymph inhibits hemolysin production by Staphylococcus aureus. We purified a factor in the silkworm hemolymph responsible for this inhibitory activity. The final fraction with the greatest specific activity contained 220- and 74-kDa proteins. Determination of the N-terminal amino acid sequence revealed that the 220- and 74-kDa proteins were apolipophorin I and apolipophorin II, respectively, indicating that the factor was apolipophorin (ApoLp). The purified ApoLp fraction showed decreased expression of S. aureus hla encoding α-hemolysin, hlb encoding β-hemolysin, saeRS, and RNAIII, which activate the expression of these hemolysin genes. Injection of an anti-ApoLp antibody into the hemolymph increased the sensitivity of silkworms to the lethal effect of S. aureus. Hog gastric mucin, a mammalian homologue of ApoLp, decreased the expression of S. aureus hla and hlb. These findings suggest that ApoLp in the silkworm hemolymph inhibits S. aureus virulence and contributes to defense against S. aureus infection and that its activity is conserved in mammalian mucin. PMID:21937431

  15. Pathogenesis of Staphylococcus aureus Bloodstream Infections

    Science.gov (United States)

    Thomer, Lena; Schneewind, Olaf; Missiakas, Dominique

    2016-01-01

    Staphylococcus aureus , a Gram-positive bacterium colonizing nares, skin, and the gastrointestinal tract, frequently invades the skin, soft tissues, and bloodstreams of humans. Even with surgical and antibiotic therapy, bloodstream infections are associated with significant mortality. The secretion of coagulases, proteins that associate with and activate the host hemostatic factor prothrombin, and the bacterial surface display of agglutinins, proteins that bind polymerized fibrin, are key virulence strategies for the pathogenesis of S. aureus bloodstream infections, which culminate in the establishment of abscess lesions. Pathogen-controlled processes, involving a wide spectrum of secreted factors, are responsible for the recruitment and destruction of immune cells, transforming abscess lesions into purulent exudate, with which staphylococci disseminate to produce new infectious lesions or to infect new hosts. Research on S. aureus bloodstream infections is a frontier for the characterization of protective vaccine antigens and the development of immune therapeutics aiming to prevent disease or improve outcomes. PMID:26925499

  16. Staphylococcus aureus pathogenesis in diverse host environments

    Science.gov (United States)

    Balasubramanian, Divya; Harper, Lamia; Shopsin, Bo; Torres, Victor J.

    2017-01-01

    Abstract Staphylococcus aureus is an eminent human pathogen that can colonize the human host and cause severe life-threatening illnesses. This bacterium can reside in and infect a wide range of host tissues, ranging from superficial surfaces like the skin to deeper tissues such as in the gastrointestinal tract, heart and bones. Due to its multifaceted lifestyle, S. aureus uses complex regulatory networks to sense diverse signals that enable it to adapt to different environments and modulate virulence. In this minireview, we explore well-characterized environmental and host cues that S. aureus responds to and describe how this pathogen modulates virulence in response to these signals. Lastly, we highlight therapeutic approaches undertaken by several groups to inhibit both signaling and the cognate regulators that sense and transmit these signals downstream. PMID:28104617

  17. Staphylococcus aureus spa type t437

    DEFF Research Database (Denmark)

    Glasner, C; Pluister, G; Westh, H

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) belonging to the multilocus sequence type clonal complex 59 (MLST CC59) is the predominant community-associated MRSA clone in Asia. This clone, which is primarily linked with the spa type t437, has so far only been reported in low numbers among...... included. Most isolates were shown to be monophyletic with 98% of the isolates belonging to the single MLVA complex 621, to which nearly all included isolates from China also belonged. More importantly, all MLST-typed isolates belonged to CC59. Our study implies that the European S. aureus t437 population...... large epidemiological studies in Europe. Nevertheless, the overall numbers identified in some Northern European reference laboratories have increased during the past decade. To determine whether the S. aureus t437 clone is present in other European countries, and to assess its genetic diversity across...

  18. Prevalence of infective endocarditis in patients with Staphylococcus aureus bacteraemia

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Høst, Ulla; Arpi, Magnus

    2011-01-01

    Aims Staphylococcus aureus infective endocarditis (IE) is a critical medical condition associated with a high morbidity and mortality. In the present study, we prospectively evaluated the importance of screening with echocardiography in an unselected S. aureus bacteraemia (SAB) population. Methods...

  19. Mode of action of Buddleja cordata verbascoside against Staphylococcus aureus.

    Science.gov (United States)

    Avila, J G; de Liverant, J G; Martínez, A; Martínez, G; Muñoz, J L; Arciniegas, A; Romo de Vivar, A

    1999-07-01

    We evaluate the mode of action of verbascoside obtained from Buddleja cordata against Staphylococcus aureus by killing kinetics and incorporation of precursors methods. Verbascoside induced lethal effect on S. aureus, by affecting protein synthesis and inhibiting leucine incorporation.

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

    DEFF Research Database (Denmark)

    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.......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....

  1. Methicillin-resistant Staphylococcus aureus in Zimbabwe.

    Science.gov (United States)

    Mauchaza, Kathrine; Madzimbamuto, Farai D; Waner, Seymour

    2016-06-01

    The prevalence of Methicillin Resistant Staphylococcus aureus (MRSA) in Africa is sparsely documented. In Zimbabwe there is no routine patient or specimen screening for MRSA. The aim of this study was to document the presence and epidemiology of MRSA in Zimbabwe. The study was done in one private sector laboratory with a national network that serves both public and private hospitals. The sample population included in-patients and outpatients, all ages, both genders, all races and only one positive specimen per patient was counted. Specimens testing positive for Staphylococcus aureus in this laboratory were further tested for MRSA using cefoxitin, by standard laboratory procedures. Data was collected from 1(st) June 2013 to 31(st) May 2014. MRSA was positive in 30 of 407 [7.0%] cases of Stapylococcus aureus reported from the laboratory. All age groups were affected from neonates to geriatrics. All specimens had similar antibiotic susceptibility pattern. Resistance was high for most widely used drugs in Zimbabwe with high sensitivity to vancomycin, linezolid and teicoplanin. Although there are no recent reports in the literature of the presence of MRSA in Zimbabwe, this study documented a 7.0% prevalence. Resistance to common antibiotics is high and antibiotic oversight is required to control the emergence of resistance to these few expensive drugs. Study was supported by Department of Anaesthesia and Critical Care funds.

  2. Revisiting Methicillin-Resistant Staphylococcus aureus Infections.

    Science.gov (United States)

    Waness, Abdelkarim

    2010-01-01

    Within less than 50 years, methicillin-resistant Staphylococcus aureus (MRSA) made a tremendous impact worldwide. It is not limited to medical facilities and healthcare institutions anymore. Indeed since two decades, cases of MRSA infections arising from the community among apparently healthy individuals are increasing. In this paper, I will present a case of community-associated MRSA sepsis followed by a comprehensive review about the history, pathogenesis, epidemiology, clinical presentations, diagnostic modalities, therapeutic options, contributing factors, growing cost and other pertinent elements of this newly evolving epidemic of MRSA infections.

  3. Revisiting methicillin-resistant Staphylococcus aureus infections

    Directory of Open Access Journals (Sweden)

    Waness Abdelkarim

    2010-01-01

    Full Text Available Within less than 50 years, methicillin-resistant Staphylococcus aureus (MRSA made a tremendous impact worldwide. It is not limited to medical facilities and healthcare institutions anymore. Indeed since two decades, cases of MRSA infections arising from the community among apparently healthy individuals are increasing. In this paper, I will present a case of community-associated MRSA sepsis followed by a comprehensive review about the history, pathogenesis, epidemiology, clinical presentations, diagnostic modalities, therapeutic options, contributing factors, growing cost and other pertinent elements of this newly evolving epidemic of MRSA infections.

  4. The prevalence and resistivity pattern of Staphylococcus Aureus ...

    African Journals Online (AJOL)

    Based on reported cases of increased multi-antibiotic resistance of Staphylococcus aureus, this study investigates the prevalence and resistivity pattern of Staphylococcus aureus isolates from ear and nasal swabs of apparently healthy students. A total of 100 samples comprising 50 nasal and 50 ear swabs, were collected ...

  5. Toxicity test and bacteriophage typing of Staphylococcus aureus ...

    African Journals Online (AJOL)

    Toxicity test and bacteriophage typing of Staphylococcus aureus isolates from food contact surfaces and foods prepared by families in Zaria, Nigeria. ... contamination of products by toxigenic strains of organisms. Keywords: Staphylococcus aureus, enterotoxin production, phage typing, haemolysis and food poisoning ...

  6. Nasal carriage of Methicillin resistant Staphylococcus aureus with ...

    African Journals Online (AJOL)

    Nasal carriage of Methicillin resistant Staphylococcus aureus with reduced Vancomycin susceptibility (MRSA-RVS) by healthy adults in Zaria, Nigeria. ... Abstract. Staphylococcus aureus isolates were collected from anterior nares of fifty healthy adults in Zaria and their antibiotic susceptibility patterns determined. 72% of the ...

  7. Staphylococcus aureus bacteraemia in children: a formidable foe ...

    African Journals Online (AJOL)

    Staphylococcus aureus remains one of the most common causes of bacteraemia in children. In order to evade and overcome the immune responses of its host and any antimicrobial therapies aimed at destroying it, this organism, through various mechanisms, continues to evolve. Staphylococcus aureus bacteraemia is a ...

  8. Brands Of Ampiclox Against Clinical Strains Of Staphylococcus aureus

    African Journals Online (AJOL)

    ... relevant factor in the antibiotic resistance of Staphylococcus aureus. Consequently the antibiogram and susceptibility of 20 clinical strains and a control strain (NCTC 6571) of Staphylococcus aureus to 10 different brands of ampiclox were determined by disk diffusion and tube broth dilution methods. The control strain was

  9. A Survey of Antibiotic Resistant Staphylococcus Aureus Strains from ...

    African Journals Online (AJOL)

    A survey of antibiotic resistant Staphylococcus aureus strains from clinical specimens was carried out. A total of 100 different clinical specimens were investigated with a yield of 48 Staphylococcus aureus isolates. A high resistance of 95.8% to penicillin, 89.6% to ampicillin, 87.5% to tetracycline, and 75.0% to ...

  10. Prevalence and risk factors for Staphylococcus aureus and ...

    African Journals Online (AJOL)

    Prevalence and risk factors for Staphylococcus aureus and methicillin‑resistant Staphylococcus aureus nasal carriage inpatients in a tertiary care hospital's chest clinic in Turkey. ... of the participants and risk factors for carriage. Fisher's exact test, univariate and multivariate logistic regression analysis were used. A P < 0.05 ...

  11. Prevalence of Methicillin-Resistant Staphylococcus aureus among ...

    African Journals Online (AJOL)

    Purpose: To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in apparently healthy ... treatment failures is vital. Keywords: Methicillin-resistant Staphylococcus aureus, Nasal swabs, Multidrug resistance, Rational .... defined as resistance to three or more classes of antibiotics other than the ...

  12. Prevalence of Staphylococcus aureus and methicillin resistant Staphylococcus aureus (MRSA) in the oral cavity.

    Science.gov (United States)

    Koukos, Georgios; Sakellari, Dimitra; Arsenakis, Minas; Tsalikis, Lazaros; Slini, Theodora; Konstantinidis, Antonios

    2015-09-01

    To assess the prevalence of Staphylococcus aureus and methicillin resistant Staphylococcus aureus (MRSA) in plaque and tongue samples from systemically healthy subjects with periodontal health, gingivitis or chronic periodontitis. After screening 720 potentially eligible subjects, 154 systemically healthy participants were ultimately enrolled in the current study. Subgingival samples were taken from the first molars and the tongue and analyzed for the presence of S. aureus and MRSA by polymerase chain reaction (PCR), using primers and conditions previously described in the literature. In addition, samples were taken from deep periodontal pockets of chronic periodontitis patients. Statistical analysis was performed by applying non-parametric tests (Kruskal-Wallis for clinical parameters, and z-test with Bonferroni corrections for distributions of assessed parameters). All comparisons were set at the 0.05 significance level. S. aureus was detected in 18% of all participants and in 10% of the samples tested. No significant differences were found in its distribution among the three investigated groups (z-test for proportions with Bonferroni corrections, p>0.05). The mecA gene was not present in any of the S. aureus found. S. aureus can be found in the oral environment regardless of the periodontal conditions and therefore should be considered as a member of the transient flora not participating in periodontal pathology. Subgingival sites and tongue surfaces seem to be an unusual habitat of MRSA. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Survival of Staphylococcus aureus on fomites.

    Science.gov (United States)

    Cuesta, Alicia; Nastri, Natalia; Bernat, Maria; Brusca, Maria; Turcot, Liliana; Nastri, Maria; Rosa, Alcira C

    2008-01-01

    The aim of this study was to evaluate duration of survival of Staphylococcus aureus on contaminated standardized fomites, such as sterilization paper (SP) and polyester previously sterilized in a steam autoclave, and to determine the potential inhibitory effects of the substrates (fabrics used to manufacture garments and special wrapping paper used in the dental setting) using the bacteriostasis test. The test was performed on two types of sterile standardized samples (T1 and T2). Sterility of the samples was validated following the protocol in use at the Department of Microbiology, after which the samples were inoculated with 50 microl of a calibrated suspension of Staphylococcus aureus (reference strain ATCC 25923) in the exponential growth phase, in a final concentration of 10(7) cfu/ml and 10(6) cfu/ml). The samples were incubated at 27 degrees C and survival and concentration of microorganisms attached to the surface of the substrates was determined at the following experimental time points: immediately post-contamination, and 3 hours, 24 hours, 3 days, and 7 days post-contamination. Recovery was determined and expressed as a percentage; the bacteriostasis test was performed and showed negative results. Our results suggest that the quantity of recovered microorganisms varies according to the type of substrate and that there is a relation between survival and incubation time of the inoculated substrate serving as an artificial niche.

  14. Prevalence and resistance of commensal Staphylococcus aureus, including meticillin-resistant S aureus, in nine European countries: a cross-sectional study.

    NARCIS (Netherlands)

    Heijer, C.D.J. den; Bijnen, E.M.E. van; Paget, W.J.; Pringle, M.; Goossen, H.; Bruggeman, C.A.; Schellevis, F.G.; Stobberingh, E.E.

    2013-01-01

    Background: Information about the prevalence of Staphylococcus aureus resistance to antimicrobial drugs has mainly been obtained from invasive strains, although the commensal microbiota is thought to be an important reservoir of resistance. We aimed to compare the prevalence of nasal S aureus

  15. Transfer of resistance plasmids from Staphylococcus epidermidis to Staphylococcus aureus: evidence for conjugative exchange of resistance.

    OpenAIRE

    Forbes, B A; Schaberg, D R

    1983-01-01

    The ability of Staphylococcus epidermidis to transfer antimicrobial resistance to Staphylococcus aureus was tested by mixed culture on filter membranes. Two of six clinical isolates examined were able to transfer resistance to S. aureus strains 879R4RF, RN450RF, and UM1385RF. Subsequent S.aureus transconjugants resulting from matings with S. epidermidis donors were able to serve as donors to other S. aureus strains at similar frequencies. Cell-free and mitomycin C-induced filtrates of donors ...

  16. A pig model of acute Staphylococcus aureus induced pyemia

    DEFF Research Database (Denmark)

    Nielsen, O. L.; Iburg, T.; Aalbæk, B.

    2009-01-01

    Background: Sepsis caused by Staphylococcus aureus constitutes an important cause of morbidity and mortality in humans, and the incidence of this disease-entity is increasing. In this paper we describe the initial microbial dynamics and lesions in pigs experimentally infected with S. aureus....... aureus isolated from man and an extension of the timeframe aiming at inducing sepsis, severe sepsis and septic shock....

  17. Multidrug-Resistant Staphylococcus aureus in US Meat and Poultry.

    Science.gov (United States)

    Waters, Andrew E; Contente-Cuomo, Tania; Buchhagen, Jordan; Liu, Cindy M; Watson, Lindsey; Pearce, Kimberly; Foster, Jeffrey T; Bowers, Jolene; Driebe, Elizabeth M; Engelthaler, David M; Keim, Paul S; Price, Lance B

    2011-05-01

    We characterized the prevalence, antibiotic susceptibility profiles, and genotypes of Staphylococcus aureus among US meat and poultry samples (n = 136). S. aureus contaminated 47% of samples, and multidrug resistance was common among isolates (52%). S. aureus genotypes and resistance profiles differed significantly among sample types, suggesting food animal-specific contamination.

  18. Methicillin-Susceptible, Vancomycin-Resistant Staphylococcus aureus, Brazil

    OpenAIRE

    Panesso , Diana; Planet , Paul J.; Diaz , Lorena; Hugonnet , Jean-Emannuel; Tran , Truc T.; Narechania , Apurva; Munita , José M.; Rincon , Sandra; Carvajal , Lina P.; Reyes , Jinnethe; Londono , Alejandra; Smith , Hannah; Sebra , Robert; Deikus , Gintaras; Weinstock , George M

    2015-01-01

    International audience; We report characterization of a methicillin-susceptible, vancomycin-resistant bloodstream isolate of Staphylococcus aureus recovered from a patient in Brazil. Emergence of vancomycin resistance in methicillin-susceptible S. aureus would indicate that this resistance trait might be poised to disseminate more rapidly among S. aureus and represents a major public health threat.

  19. Aspartate inhibits Staphylococcus aureus biofilm formation.

    Science.gov (United States)

    Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

    2015-04-01

    Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Staphylococcus lugdunensis, a serious pathogen in periprosthetic joint infections: comparison to Staphylococcus aureus and Staphylococcus epidermidis.

    Science.gov (United States)

    Lourtet-Hascoët, J; Bicart-See, A; Félicé, M P; Giordano, G; Bonnet, E

    2016-10-01

    The aim of this study was to assess the characteristics of periprosthetic joint infection (PJI) due to Staphylococcus lugdunensis and to compare these to the characteristics of PJI due to Staphylococcus aureus and Staphylococcus epidermidis. A retrospective multicentre study including all consecutive cases of S. lugdunensis PJI (2000-2014) was performed. Eighty-eight cases of staphylococcal PJI were recorded: 28 due to S. lugdunensis, 30 to S. aureus, and 30 to S. epidermidis, as identified by Vitek 2 or API Staph (bioMérieux). Clinical symptoms were more often reported in the S. lugdunensis group, and the median delay between surgery and infection was shorter for the S. lugdunensis group than for the S. aureus and S. epidermidis groups. Regarding antibiotic susceptibility, the S. lugdunensis strains were susceptible to antibiotics and 61% of the patients could be treated with levofloxacin + rifampicin. The outcome of the PJI was favourable for 89% of patients with S. lugdunensis, 83% with S. aureus, and 97% with S. epidermidis. S. lugdunensis is an emerging pathogen with a pathogenicity quite similar to that of S. aureus. This coagulase-negative Staphylococcus must be identified precisely in PJI, in order to select the appropriate surgical treatment and antibiotics . Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  1. Diabetes and early postpartum methicillin-resistant Staphylococcus aureus infection in US hospitals

    NARCIS (Netherlands)

    Parriott, Andrea M.; Arah, Onyebuchi A.

    2013-01-01

    The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) infection in postpartum women is not well characterized. Because diabetes is a risk factor for some infections, we sought to characterize the relationship between diabetes and invasive MRSA infections in women admitted to US

  2. Future challenges and treatment of Staphylococcus aureus bacteremia with emphasis on MRSA

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Fowler, Vance G; Skov, Robert

    2011-01-01

    Staphylococcus aureus bacteremia (SAB) is an urgent medical problem due to its growing frequency and its poor associated outcome. As healthcare delivery increasingly involves invasive procedures and implantable devices, the number of patients at risk for SAB and its complications is likely to gro...

  3. SDS Interferes with SaeS Signaling of Staphylococcus aureus Independently of SaePQ

    NARCIS (Netherlands)

    Makgotlho, Phuti E.; Marincola, Gabriella; Schaefer, Daniel; Liu, Qian; Bae, Taeok; Geiger, Tobias; Wasserman, Elizabeth; Wolz, Christiane; Ziebuhr, Wilma; Sinha, Bhanu

    2013-01-01

    The Staphylococcus aureus regulatory saePQRS system controls the expression of numerous virulence factors, including extracellular adherence protein (Eap), which amongst others facilitates invasion of host cells. The saePQRS operon codes for 4 proteins: the histidine kinase SaeS, the response

  4. Antimicrobial peptide exposure selects for Staphylococcus aureus resistance to human defence peptides

    DEFF Research Database (Denmark)

    Kubicek-Sutherland, Jessica Z.; Lofton, Hava; Vestergaard, Martin

    2017-01-01

    of sepsis. Results: AMP-resistant Staphylococcus aureus mutants often displayed little to no fitness cost and caused invasive disease in mice. Further, this phenotype coincided with diminished susceptibility to both clinically prescribed antibiotics and human defence peptides. Conclusions: These findings...

  5. Molecular coordination of Staphylococcus aureus cell division

    Science.gov (United States)

    Cotterell, Bryony E; Walther, Christa G; Fenn, Samuel J; Grein, Fabian; Wollman, Adam JM; Leake, Mark C; Olivier, Nicolas; Cadby, Ashley; Mesnage, Stéphane; Jones, Simon

    2018-01-01

    The bacterial cell wall is essential for viability, but despite its ability to withstand internal turgor must remain dynamic to permit growth and division. Peptidoglycan is the major cell wall structural polymer, whose synthesis requires multiple interacting components. The human pathogen Staphylococcus aureus is a prolate spheroid that divides in three orthogonal planes. Here, we have integrated cellular morphology during division with molecular level resolution imaging of peptidoglycan synthesis and the components responsible. Synthesis occurs across the developing septal surface in a diffuse pattern, a necessity of the observed septal geometry, that is matched by variegated division component distribution. Synthesis continues after septal annulus completion, where the core division component FtsZ remains. The novel molecular level information requires re-evaluation of the growth and division processes leading to a new conceptual model, whereby the cell cycle is expedited by a set of functionally connected but not regularly distributed components. PMID:29465397

  6. Fibronectin-binding protein acts as Staphylococcus aureus invasin via fibronectin bridging to integrin alpha5beta1

    NARCIS (Netherlands)

    Sinha, B; François, P P; Nüsse, O; Foti, M; Hartford, O M; Vaudaux, P; Foster, T J; Lew, D P; Herrmann, M; Krause, K H

    The ability of Staphylococcus aureus to invade mammalian cells may explain its capacity to colonize mucosa and to persist in tissues after bacteraemia. To date, the underlying molecular mechanisms of cellular invasion by S. aureus are unknown, despite its high prevalence and difficulties in

  7. Methicillin-resistant Staphylococcus aureus: the superbug.

    Science.gov (United States)

    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. Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  8. Food poisoning and Staphylococcus aureus enterotoxins.

    Science.gov (United States)

    Argudín, María Ángeles; Mendoza, María Carmen; Rodicio, María Rosario

    2010-07-01

    Staphylococcus aureus produces a wide variety of toxins including staphylococcal enterotoxins (SEs; SEA to SEE, SEG to SEI, SER to SET) with demonstrated emetic activity, and staphylococcal-like (SEl) proteins, which are not emetic in a primate model (SElL and SElQ) or have yet to be tested (SElJ, SElK, SElM to SElP, SElU, SElU2 and SElV). SEs and SEls have been traditionally subdivided into classical (SEA to SEE) and new (SEG to SElU2) types. All possess superantigenic activity and are encoded by accessory genetic elements, including plasmids, prophages, pathogenicity islands, vSa genomic islands, or by genes located next to the staphylococcal cassette chromosome (SCC) implicated in methicillin resistance. SEs are a major cause of food poisoning, which typically occurs after ingestion of different foods, particularly processed meat and dairy products, contaminated with S. aureus by improper handling and subsequent storage at elevated temperatures. Symptoms are of rapid onset and include nausea and violent vomiting, with or without diarrhea. The illness is usually self-limiting and only occasionally it is severe enough to warrant hospitalization. SEA is the most common cause of staphylococcal food poisoning worldwide, but the involvement of other classical SEs has been also demonstrated. Of the new SE/SEls, only SEH have clearly been associated with food poisoning. However, genes encoding novel SEs as well as SEls with untested emetic activity are widely represented in S. aureus, and their role in pathogenesis may be underestimated.

  9. Curcumin Reverse Methicillin Resistance in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Su-Hyun Mun

    2014-11-01

    Full Text Available 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 action of curcumin was analyzed by the viability assay in the presence of detergents, ATPase inhibitors and peptidoglycan (PGN from S. aureus, and the PBP2a protein level was analyzed by western blotting. The morphological changes in the curcumin-treated MRSA strains were investigated by transmission electron microscopy (TEM. We analyzed increased susceptibility to MRSA isolates in the presence of curcumin. The optical densities at 600 nm (OD600 of the suspensions treated with the combinations of curcumin with triton X-100 and Tris were reduced to 63% and 59%, respectively, compared to curcumin without treatment. N,N'-dicyclohexylcarbodiimide (DCCD and sodium azide (NaN3 were reduced to 94% and 55%, respectively. When peptidoglycan (PGN from S. aureus was combined with curcumin, PGN (0–125 μg/mL gradually blocked the antibacterial activity of curcumin (125 μg/mL; however, at a concentration of 125 µg/mL PGN, it did not completely block curcumin. Curcumin has a significant effect on the protein level of PBP2a. The TEM images of MRSA showed damage of the cell wall, disruption of the cytoplasmic contents, broken cell membrane and cell lysis after the treatment of curcumin. These data indicate a remarkable antibacterial effect of curcumin, with membrane permeability enhancers and ATPase inhibitors, and curcumin did not directly bind to PGN on the cell wall. Further, the antimicrobial action of curcumin involved in the PBP2a-mediated resistance mechanism was

  10. Staphylococcus aureus: resistance pattern and risk factors

    Directory of Open Access Journals (Sweden)

    Mohammad Naghavi-Behzad

    2015-03-01

    Full Text Available Introduction: Methicillin resistant Staphylococcus aureus (MRSA has emerged as a nosocomial pathogen of major worldwide importance and is an increasingly frequent cause of community-acquired infections. In this study, different risk factors and MRSA resistance pattern were investigated. Methods: In a 24 months period, all of the patients who were confined to bed in the surgery ward were included in the study. Then they were assessed to find out as if they had MRSA infection when hospitalized and once when they were discharged. Almost 48 h after admission, when patients were discharged, social and medical histories were acquired. Acquired samples were examined. Results: During the present study of 475 patients, 108 patients (22.8% had S. aureus. About frequency of antibiotic resistance among collected S. aureus colonies, erythromycin resistance, was the most frequent antibiotic resistance, also resistance to vancomycin was 0.4% that was the least. Only hospitalization duration had statistically significant correlation with antibiotic resistance, also resistance to erythromycin had statistically significant relation with history of surgery and alcohol consumption. Of all 34 MRSA species, 22 (64.7% samples were resistant to erythromycin, 17 (50.0% resistant to cefoxitin, 5 (14.7% resistant to mupirocin, 1 (2.9% resistant to vancomycin and 1 (2.9% resistant to linezolid. Conclusion: The results of the current study show that among hospitalized patients, there is resistance against methicillin. Since based on results of the study there is resistance against oxacillin and erythromycin in most cases, administering appropriate antibiotics have an important role in minimizing the resistance burden among bacterial species.

  11. Methicillin resistant Staphylococcus aureus in Ethiopia: a meta-analysis.

    Science.gov (United States)

    Eshetie, Setegn; Tarekegn, Fentahun; Moges, Feleke; Amsalu, Anteneh; Birhan, Wubet; Huruy, Kahsay

    2016-11-21

    The burden of methicillin resistant Staphylococcus aureus is a major public health concern worldwide; however the overall epidemiology of multidrug resistant strains is neither coordinated nor harmonized, particularly in developing countries including Ethiopia. Therefore, the aim of this meta-analysis was to assess the burden of methicillin resistant Staphylococcos aureus and its antibiotic resistance pattern in Ethiopia at large. PubMed, Google Scholar, and lancet databases were searched and a total of 20 studies have been selected for meta-analysis. Six authors have independently extracts data on the prevalence of methicillin resistant Staphylococcus aureus among clinical isolates of Staphylococcus aureus. Statistical analysis was achieved by using Open meta-analyst (version 3.13) and Comprehensive meta-analysis (version 3.3) softwares. The overall prevalence of methicillin resistant Staphylococcus aureus and its antibiotic resistance pattern were pooled by using the forest plot, table and figure with 95% CI. The pooled prevalence of methicillin resistant Staphylococcus aureus was 32.5% (95% CI, 24.1 to 40.9%). Moreover, methicillin resistant Staphylococcus aureus strains were found to be highly resistant to penicillin, ampicillin, erythromycin, and amoxicillin, with a pooled resistance ratio of 99.1, 98.1, 97.2 and 97.1%, respectively. On the other hand, comparably low levels of resistance ratio were noted to vancomycin, 5.3%. The overall burden of methicillin resistant Staphylococcus aureus is considerably high, besides these strains showed extreme resistance to penicillin, ampicillin, erythromycin and amoxicillin. In principle, appropriate use of antibiotics, applying safety precautions are the key to reduce the spread of multidrug resistant strains, methicillin resistant Staphylococcus aureus in particular.

  12. Surgimiento y diseminación de Staphylococcus aureus meticilinorresistente Staphylococcus aureus methicillin-resistant: emergence and dissemination

    Directory of Open Access Journals (Sweden)

    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.

  13. Beta-hemolysin promotes skin colonization by Staphylococcus aureus.

    Science.gov (United States)

    Katayama, Yuki; Baba, Tadashi; Sekine, Miwa; Fukuda, Minoru; Hiramatsu, Keiichi

    2013-03-01

    Colonization by Staphylococcus aureus is a characteristic feature of several inflammatory skin diseases and is often followed by epidermal damage and invasive infection. In this study, we investigated the mechanism of skin colonization by a virulent community-acquired methicillin-resistant S. aureus (CA-MRSA) strain, MW2, using a murine ear colonization model. MW2 does not produce a hemolytic toxin, beta-hemolysin (Hlb), due to integration of a prophage, Sa3mw, inside the toxin gene (hlb). However, we found that strain MW2 bacteria that had successfully colonized murine ears included derivatives that produced Hlb. Genome sequencing of the Hlb-producing colonies revealed that precise excision of prophage Sa3mw occurred, leading to reconstruction of the intact hlb gene in their chromosomes. To address the question of whether Hlb is involved in skin colonization, we constructed MW2-derivative strains with and without the Hlb gene and then subjected them to colonization tests. The colonization efficiency of the Hlb-producing mutant on murine ears was more than 50-fold greater than that of the mutant without hlb. Furthermore, we also showed that Hlb toxin had elevated cytotoxicity for human primary keratinocytes. Our results indicate that S. aureus Hlb plays an important role in skin colonization by damaging keratinocytes, in addition to its well-known hemolytic activity for erythrocytes.

  14. Investigational drugs to treat methicillin-resistant Staphylococcus aureus

    Science.gov (United States)

    Vuong, Cuong; Yeh, Anthony J; Cheung, Gordon YC; Otto, Michael

    2016-01-01

    Introduction Staphylococcus aureus remains one of the leading causes of morbidity and mortality worldwide. This is to a large extent due to antibiotic-resistant strains, in particular methicillin-resistant S. aureus (MRSA). While the toll of invasive MRSA infections appears to decrease in U.S. hospitals, the rate of community-associated MRSA infections remains constant and there is a surge of MRSA in many other countries. This situation calls for continuing if not increased efforts to find novel strategies to combat MRSA infections. Areas covered This review will provide an overview of current investigational antibiotics in clinical development (up to phase II), and of therapeutic antibodies and alternative drugs against S. aureus in preclinical and clinical development, including a short description of the mechanism of action and a presentation of microbiological and clinical data. Expert opinion Increased recent antibiotic development efforts and results from pathogenesis research have led to several new antibiotics and alternative drugs, as well as a more informed selection of targets for vaccination efforts against MRSA. This developing portfolio of novel anti-staphylococcal drugs will hopefully provide us with additional and more efficient ways to combat MRSA infections in the near future and prevent us from running out of treatment options, even if new resistances arise. PMID:26536498

  15. Host- and tissue-specific pathogenic traits of Staphylococcus aureus.

    NARCIS (Netherlands)

    W.B. van Leeuwen (Willem); D.C. Melles (Damian); A. Alaidan (Alwaleed); M. Al-Ahdal (Mohammed); H.A.M. Boelens (Hélène); S.V. Snijders (Susan); H.F.L. Wertheim (Heiman); E. van Duijkeren (Engeline); J.K. Peeters (Justine); P.J. van der Spek (Peter); R.F.J. Gorkink (Raymond); G. Simons (Guus); H.A. Verbrugh (Henri); A.F. van Belkum (Alex)

    2005-01-01

    textabstractComparative genomics were used to assess genetic differences between Staphylococcus aureus strains derived from infected animals versus colonized or infected humans. A total of 77 veterinary isolates were genetically characterized by high-throughput amplified fragment length polymorphism

  16. A Closer Look at the Transcriptome of Staphylococcus aureus

    NARCIS (Netherlands)

    Smits, N.J.P.

    2012-01-01

    Tight regulation of genes upon changing environments is important in establishing and maintaining infections by pathogens. In Staphylococcus aureus, gene expression and particularly controlled expression of various groups of genes dependent on growth and environmental conditions is essential for

  17. Strategies for Prevention of Methicillin Resistant Staphylococcus aureus (MRSA) Infections and Decolonization.

    Science.gov (United States)

    Kaushik, Ashlesha; Wagner, Cassie; Consoer, Hollie; Chatterjee, Archana

    2016-12-01

    Methicillin resistant Staphylococcus aureus (MRSA) invasive infections can be severe in the pediatric population with high morbidity and mortality. MRSA colonization can predispose to recurrent skin and soft tissue infections and invasive MRSA disease and is a frequent challenge faced by clinicians. This article reviews the importance of MRSA as a pathogen, MRSA colonization and various MRSA decolonization strategies. Copyright© South Dakota State Medical Association.

  18. An Improved Medium for Growing Staphylococcus aureus Biofilm

    Science.gov (United States)

    2012-04-19

    Note An improved medium for growing Staphylococcus aureus biofilm Ping Chen, Johnathan J. Abercrombie, Nicole R. Jeffrey, Kai P. Leung ⁎ Microbiology...Branch, US Army Dental and Trauma Research Detachment, Institute of Surgical Research, Fort Sam Houston, TX 78234, United States a b s t r a c ta r t...Keywords: Staphylococcus aureus Biofilm Human plasma Microfluidic A medium (Brain Heart Infusion plus 10% human plasma) was developed, tested, and

  19. Future challenges and treatment of Staphylococcus aureus bacteremia with emphasis on MRSA

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Fowler, Vance G; Skov, Robert

    2011-01-01

    Staphylococcus aureus bacteremia (SAB) is an urgent medical problem due to its growing frequency and its poor associated outcome. As healthcare delivery increasingly involves invasive procedures and implantable devices, the number of patients at risk for SAB and its complications is likely to grow....... Compounding this problem is the growing prevalence of methicillin-resistant S. aureus (MRSA) and the dwindling efficacy of vancomycin, long the treatment of choice for this pathogen. Despite the recent availability of several new antibiotics for S. aureus, new strategies for treatment and prevention...

  20. Root cause analysis of methicillin resistant Staphylococcus aureus bacteraemia.

    Science.gov (United States)

    Aslam, Nadia; Mehdi, Naima; Izhar, Mateen

    2015-10-01

    To find the important risk factors and sources of bacteraemia in patients suffering from methicillin-resistant staphylococcus aureus bacteraemia. The descriptive study was carried out at Shaikh Zayed Hospital, Lahore, from October 2010 to August 2011. Blood cultures were processed to isolate methicillin-resistant staphylococcus aureus. A questionnaire was completed by the participating patients suffering from bacteraemia. Information about risk factors present at the time and risk factors that served as the source of bacteraemia were noted. Total 4058 blood cultures were processed and 669(16.5%) were positive. Of them, 194(29%) cultures were found to be positive for staphylococci. Out of these 194 blood cultures, coagulase-negative staphylococci were isolated from 117(60%), and 77(40%) were positive for S. aureus. Out of these 77 samples, 26(34%) were found to be methicillin-sensitive staphylococcus aureus and 51(66%) were methicillin-resistant staphylococcus aureus. The overall frequency of methicillin-resistant staphylococcus aureus was 1.25%; 7.62% out of positive blood culture; 26.28% out of total staphylococci; and 66% out of total S. aureus. As for the source of infection, central venous pressure line 11(21.6%), post-influenza pneumonia 9(17.6%), peripheral intravenous line 8(15.7%) and dialysis line 7(13.7%) were major reasons. Taking care of aseptic measures while insertion, frequent change and early removal of the central venous and dialysis lines is of critical significance.

  1. Staphylococcus aureus Hijacks a Skin Commensal to Intensify Its Virulence: Immunization Targeting β-Hemolysin and CAMP Factor

    OpenAIRE

    Lo, Chih-Wei; Lai, Yiu-Kay; Liu, Yu-Tsueng; Gallo, Richard L.; Huang, Chun-Ming

    2010-01-01

    The need for a new anti-Staphylococcus aureus therapy that can effectively cripple bacterial infection, neutralize secretory virulence factors, and lower the risk of creating bacterial resistance is undisputed. Here, we propose what is, to our knowledge, a previously unreported infectious mechanism by which S. aureus may commandeer Propionibacterium acnes, a key member of the human skin microbiome, to spread its invasion and highlight two secretory virulence factors (S. aureus β-hemolysin and...

  2. Intercenter reproducibility of binary typing for Staphylococcus aureus

    NARCIS (Netherlands)

    van Leeuwen, Willem B.; Snoeijers, Sandor; van der Werken-Libregts, Christel; Tuip, Anita; van der Zee, Anneke; Egberink, Diane; de Proost, Monique; Bik, Elisabeth; Lunter, Bjorn; Kluytmans, Jan; Gits, Etty; van Duyn, Inge; Heck, Max; van der Zwaluw, Kim; Wannet, Wim; Noordhoek, Gerda T.; Mulder, Sije; Renders, Nicole; Boers, Miranda; Zaat, Sebastiaan; van der Riet, Daniëlle; Kooistra, Mirjam; Talens, Adriaan; Dijkshoorn, Lenie; van der Reyden, Tanny; Veenendaal, Dick; Bakker, Nancy; Cookson, Barry; Lynch, Alisson; Witte, Wolfgang; Cuny, Christa; Blanc, Dominique; Vernez, Isabelle; Hryniewicz, Waleria; Fiett, Janusz; Struelens, Marc; Deplano, Ariane; Landegent, Jim; Verbrugh, Henri A.; van Belkum, Alex

    2002-01-01

    The reproducibility of the binary typing (BT) protocol developed for epidemiological typing of Staphylococcus aureus was analyzed in a biphasic multicenter study. In a Dutch multicenter pilot study, 10 genetically unique isolates of methicillin-resistant S. aureus (MRSA) were characterized by the BT

  3. Virulence potential of Staphylococcus aureus isolates from Buruli ulcer patients

    NARCIS (Netherlands)

    Amissah, Nana Ama; Chlebowicz, Monika A.; Ablordey, Anthony; Tetteh, Caitlin S.; Prah, Isaac; van der Werf, Tjip S.; Friedrich, Alex W.; van Dijl, Jan Maarten; Stienstra, Ymkje; Rossen, John W.

    Buruli ulcer (BU) is a necrotizing infection of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. BU wounds may also be colonized with other microorganisms including Staphylococcus aureus. This study aimed to characterize the virulence factors of S. aureus isolated from BU patients.

  4. Nasal carriage of Methicillin resistant Staphylococcus aureus with ...

    African Journals Online (AJOL)

    Staphylococcus aureus isolates were collected from anterior nares of fifty healthy adults in Zaria and their antibiotic susceptibility patterns determined. 72% of the isolates were methicillin-resistant S. aureus. The isolates were generally resistant to multiple antibiotics including Chloramphenicol (78% resistance), Penicillin ...

  5. Detection of some virulence factors in Staphylococcus aureus ...

    African Journals Online (AJOL)

    pathogens that can cause mastitis, Staphylococcus aureus is probably the most lethal agent because it causes chronic and deep infection in the mammary glands that is extremely difficult to be cured. The present study was to detect some of the virulence factors in the S. aureus isolated from 360 mastitis milk samples in ...

  6. Toxins and adhesion factors associated with Staphylococcus aureus ...

    African Journals Online (AJOL)

    Staphylococcus aureus is a causative agent of acute and infectious diarrhoea. In Africa, there is no sufficient information on the virulence and the degree of factors produced by its diarrhoea-isolated strains. Clinical features and virulence factors produced by S. aureus isolated from diarrhoeal-patients admitted at the ...

  7. Nasal carriage of multi-drug resistant Staphylococcus aureus in ...

    African Journals Online (AJOL)

    Background: Nasal Staphylococcus aureus is a major source of community and hospital associated staphylococcal infections. This study determined the prevalence of nasal S. aureus isolates and investigated their antimicrobial resistance profile in healthy volunteers. Methods: Nasal specimens of healthy volunteers in ...

  8. Nasal carriage of methicilli-resistant staphylococcus aureus with ...

    African Journals Online (AJOL)

    Staphylococcus aureus isolates were collected from anterior nares of fifty healthy adults in Zaria and their antibiotic susceptibility patterns determined. Seventy-two percent (72%) of the isolates were methicillin-resistant S. aureus, while 20% were methicillin-susceptible. The isolates were generally resistant to multiple ...

  9. Detection and identification of Staphylococcus aureus in raw milk by ...

    African Journals Online (AJOL)

    Staphylococcus aureus causes foodborne diseases if consumed in contaminated milk products. Rapid detection and characterization of foodborne pathogen S. aureus is crucial for epidemiological investigations and food safety surveillance. It is still a challenge to detect and identify bacterial pathogens quickly and ...

  10. Beta Lactamase production by Staphylococcus aureus from children ...

    African Journals Online (AJOL)

    Isolates of Staphylococcus aureus from children aged 5 years and below with sporadic diarrhoea were tested for their ability to produce beta-lactamase enzyme. Of the 95 isolates tested 79 (83.2%) were beta-lactamase-producing strains. The study confirms that majority of clinical isolates of S. aureus from diarrhoeic ...

  11. Pneumonia and new methicillin-resistant Staphylococcus aureus clone.

    NARCIS (Netherlands)

    Garnier, Fabien; Tristan, Anne; François, Bruno; Etienne, Jerome; Delage-Corre, Manuella; Martin, Christian; Liassine, Nadia; Wannet, Wim; Denis, François; Ploy, Marie-Cécile

    2006-01-01

    Necrotizing pneumonia caused by Staphylococcus aureus strains carrying the Panton-Valentin leukocidin gene is a newly described disease entity. We report a new fatal case of necrotizing pneumonia. An S. aureus strain with an agr1 allele and of a new sequence type 377 was recovered, representing a

  12. Prevalence of Methicillin–Resistant Staphylococcus aureus (MRSA ...

    African Journals Online (AJOL)

    Staphylococcus aureus is a major bacterial pathogen that causes different community and hospital-acquired infections. Over time, strains of S. aureus have become resistant to different antibiotics including penicillinase-resistant penicillins. Having data on the local antimicrobial susceptibility pattern of this pathogen is ...

  13. Antibiotic resistant Staphylococcus aureus in Abia State of Nigeria ...

    African Journals Online (AJOL)

    The S. aureus. isolates varied in their antibiotic susceptibility pattern when tested for their sensitivity to 16 antibiotics. Eighty percent of the isolates were resistant to more than one antimicrobial agent. All the isolates showed resistance to nalidixic acid and 100% sensitivity to rifampicin. Key words: Staphylococcus aureus, ...

  14. Staphylococcus aureus ST398 from slaughter pigs in northeast China

    NARCIS (Netherlands)

    Yan, Xiaomei; Yu, Xiaojie; Tao, Xiaoxia; Zhang, Jianfeng; Zhang, Binghua; Dong, Rui; Xue, Chengyu; Grundmann, Hajo; Zhang, Jianzhong

    To describe the prevalence and population structure of Staphylococcus aureus bacteria that colonize pigs at slaughterhouses in northeastern China, nose swabs were collected from pigs in two slaughterhouses in Harbin, Heilongjiang Province, China in 2009.S. aureus isolates were characterized by

  15. Distribution of capsular and surface polysaccharide serotypes of Staphylococcus aureus

    NARCIS (Netherlands)

    von Eiff, Christof; Taylor, Kimberly L; Mellmann, Alexander; Fattom, Ali I; Friedrich, Alexander W.; Peters, Georg; Becker, Karsten

    Because of its ability to cause serious and fatal infections, Staphylococcus aureus remains one of the most feared microorganisms. Methicillin-resistant S. aureus (MRSA) has long been a common pathogen in healthcare facilities, but within the past decade, it has emerged as a problematic pathogen in

  16. Staphylococcus aureus from the German general population is highly diverse

    NARCIS (Netherlands)

    Becker, Karsten; Schaumburg, Frieder; Fegeler, Christian; Friedrich, Alexander W.; Kock, Robin

    Objectives: This prospective cohort study evaluates colonization dynamics and molecular characteristics of methicillin-susceptible and - resistant Staphylococcus aureus (MSSA/MRSA) in a German general population. Methods: Nasal swabs of 1878 non-hospitalized adults were screened for S. aureus.

  17. Prevalence and risk factors for Staphylococcus aureus and ...

    African Journals Online (AJOL)

    2015-09-05

    Sep 5, 2015 ... factors for colonization with methicillin‑resistant Staphylococcus aureus at the time of hospital admission. Infect Control Hosp Epidemiol 2003;24:409‑14. 16. Lu PL, Chin LC, Peng CF, Chiang YH, Chen TP, Ma L, et al. Risk factors and molecular analysis of community methicillin‑resistant Staphylococcus ...

  18. Whole Genome Sequencing of Danish Staphylococcus argenteus Reveals a Genetically Diverse Collection with Clear Separation from Staphylococcus aureus

    DEFF Research Database (Denmark)

    Hansen, Thomas A.; Bartels, Mette D.; Hogh, Silje V.

    2017-01-01

    Staphylococcus argenteus (S. argenteus) is a newly identified Staphylococcus species that has been misidentified as Staphylococcus aureus (S. aureus) and is clinically relevant. We identified 25 S. argenteus genomes in our collection of whole genome sequenced S. aureus. These genomes were compare...

  19. Evaluating vancomycin susceptibility in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Mimica MJ

    2016-09-01

    Full Text Available Marcelo J Mimica, Alessandra Navarini Department of Pathology, Division of Microbiology, Santa Casa de São Paulo School of Medicine, São Paulo, BrazilWe read the report by Phillips et al1 with great interest and would like to discuss it in comparison with our previous published data on the subject.2,3We have also studied a number of Staphylococcus aureus clinical isolates (n=125, comparing different vancomycin susceptibility tests, including microdilution, Etest® (bio-Mérieux, Marcy-l’Étoile, France, and brain heart infusion vancomycin screening plates. We found only one isolate with reduced susceptibility with a minimum inhibitory concentration (MIC =4 mg/L when tested with Etest and 2 mg/L when tested with microdilution.2,3 Our results showed a tendency of higher lethality when higher MICs were present, even within the susceptible range,3 as some previous studies have shown.4,5Concordant to Phillips et al1 and other authors,6,7 we also reported a poor correlation between different tests. Comparing Etest and microdilution (approximating an Etest MIC value between two twofold dilutions up to the highest value, 58% of the isolates had similar MICs, whereas 38% had an MIC by Etest one dilution higher than microdilution. One isolate had an Etest MIC twofold higher and four isolates an Etest MIC onefold lower than microdilution.2However, in our study, a brain heart infusion screening plate with 2.0 mg/L of vancomycin showed a sensitivity of 100% to detect isolates with an MIC ≥2.0 by Etest and 91% to detect an MIC ≥2.0 by microdilution, making this test an interesting option for initial screening of S. aureus isolates for reduced vancomycin susceptibility. Specificities were 63% and 38%, respectively, which would still make necessary the further testing with an MIC method, but in a much smaller number of isolates.2 This approach would be suitable for a large number of laboratories throughout the world where the routine MIC testing of all

  20. Methicillin-resistant Staphylococcus aureus fomite survival.

    Science.gov (United States)

    Williams, Christa; Davis, Diane L

    2009-01-01

    To assess survival of methicillin-resistant Staphylococcus aureus (MRSA) on fomites encountered by health students. Three suspensions of MRSA were made to mimic lab splashes: a 0.5 McFarland trypticase soy broth, whole blood with 50 colony forming units/mL and body fluid/serum with 2000 colony forming units/mL. These were seeded onto three environmental surfaces (glass, vinyl floor tile, and countertop) and wet swabbed for 60 days. High touch areas of student stethoscopes were also wet swabbed. MRSA selective CHROMagar was used to identify organism survival. Salisbury University, Salisbury MD PARTICIPANTS: Salisbury University nursing and respiratory therapy students who volunteered to have their stethoscopes swabbed anonymously. Detection of pink colonies on MRSA-selective CHROMagar. MRSA in 0.5 McFarland broth lived for > or =60 days on all surfaces. MRSA in blood was undetectable on any surface, and MRSA in serum survived 41 days on glass, 45 days on tile, and > or =60 days on countertop. Five of thirty-three stethoscopes (15%) tested were positive for MRSA. Previous studies showed fomite survival of MRSA for about two weeks using contact plate sampling and MRSA on 7.4% of stethoscopes. We showed longer MRSA survival times by wet swab sampling and a higher stethoscope contamination rate. As expected, higher organism loads survived longer.

  1. Predictors of Mortality in Staphylococcus aureus Bacteremia

    Science.gov (United States)

    Jensen, Slade O.; Vaska, Vikram L.; Espedido, Björn A.; Paterson, David L.; Gosbell, Iain B.

    2012-01-01

    Summary: Staphylococcus aureus bacteremia (SAB) is an important infection with an incidence rate ranging from 20 to 50 cases/100,000 population per year. Between 10% and 30% of these patients will die from SAB. Comparatively, this accounts for a greater number of deaths than for AIDS, tuberculosis, and viral hepatitis combined. Multiple factors influence outcomes for SAB patients. The most consistent predictor of mortality is age, with older patients being twice as likely to die. Except for the presence of comorbidities, the impacts of other host factors, including gender, ethnicity, socioeconomic status, and immune status, are unclear. Pathogen-host interactions, especially the presence of shock and the source of SAB, are strong predictors of outcomes. Although antibiotic resistance may be associated with increased mortality, questions remain as to whether this reflects pathogen-specific factors or poorer responses to antibiotic therapy, namely, vancomycin. Optimal management relies on starting appropriate antibiotics in a timely fashion, resulting in improved outcomes for certain patient subgroups. The roles of surgery and infectious disease consultations require further study. Although the rate of mortality from SAB is declining, it remains high. Future international collaborative studies are required to tease out the relative contributions of various factors to mortality, which would enable the optimization of SAB management and patient outcomes. PMID:22491776

  2. Pharmacotherapeutic options for treating Staphylococcus aureus bacteremia.

    Science.gov (United States)

    Gudiol, Carlota; Cuervo, Guillermo; Shaw, Evelyn; Pujol, Miquel; Carratalà, Jordi

    2017-12-01

    Case-fatality rates for Staphylococcus aureus bacteremia (SAB) remain unacceptably high and have improved only modestly in recent decades. Treatment of SAB is still a clinical challenge, especially if methicillin-resistant strains are involved. New drugs with anti-staphylococcal activity are currently available, and their role as alternatives to standard therapies is being investigated. Areas covered: In this review, we give an update of the current available antibiotics for the treatment of SAB. We provide information regarding the pharmacological characteristics, the accepted indications, and the most important adverse events of the old and new anti-staphylococcal agents, as well as the existing evidence on their use for the treatment of SAB. Expert opinion: The management of patients with SAB is very complex and needs a multidisciplinary approach. There are currently new available options for the treatment of methicillin-resistant SAB. However, more data from clinical trials are needed to assign specific roles to each antibiotic and to include them in the new antibacterial armamentarium. The role of combination therapy for the treatment of increasingly complex patients with SAB deserves thorough investigation.

  3. METICILIN REZISTENTNI STAPHYLOCOCCUS AUREUS (MRSA (in bosnian

    Directory of Open Access Journals (Sweden)

    Jasmin Dizdarević

    2017-03-01

    Full Text Available Zbog visokog stepena adaptibilnosti i postojanja velikog broja vrsta, stafilokoke spadaju u grupu široko rasprostranjenih mikroorganizama. Ove bakterije se gotovo redovno mogu naći na koži, krznu i dlaci, te sluznicama nosne šupljine i ždrijela različitih životinja i ljudi. Pojava otpornosti stafilokoka na različite grupe antibiotika, kao i potreba za boljim razumjevanjem mehanizma stafilokokne antibiotske rezistencije, predstavljaju ozbiljan izazov za efikasniju borbu sa ovim globalnim problemom. Meticilin-oksacilin rezistencija danas predstavlja poseban problem u veterinarskoj i humanoj medicini. Ekonomski gubici izazvani stafilokoknim infekcijama u stočarskoj proizvodnji širom svijeta, jedan su od najvažnijih veterinarskih problema. Visok stepen morbiditeta i dugotrajna liječenja oboljelih životinja, dodatno intenziviraju i aktualiziraju ovu problematiku. Posebnu grupu meticilin-oksacilin rezistentnih stafilokoka predstavljaju stafilokokni sojevi povezani sa stokom LA-MRSA (eng. Livestock-associated Methicillin-resistant Staphylococcus aureus. Zbog činjenice da je moguć prenos ovih mikroorganizama sa životinja na ljude, ali i obratno, koagulaza pozitivne stafilokoke zauzimaju posebno mjesto u javnom zdravstvu općenito.

  4. Nasal Staphylococcus aureus and methicillin-resistant Staphylococcus aureus carriage among college student athletes in northern Taiwan

    Directory of Open Access Journals (Sweden)

    Hong-Kai Wang

    2017-08-01

    Full Text Available Of 259 college students in northern Taiwan surveyed, nasal carriage rate of Staphylococcus aureus and methicillin-resistant S. aureus (MRSA was 22.4% and 1.54%, respectively and no significant difference was found between athlete students and non-athlete students. Three of four MRSA isolates belonged to sequence type 59, the endemic community clone.

  5. The complex biology and contribution of Staphylococcus aureus in atopic dermatitis, current and future therapies.

    Science.gov (United States)

    Hepburn, L; Hijnen, D J; Sellman, B R; Mustelin, T; Sleeman, M A; May, R D; Strickland, I

    2017-07-01

    Atopic dermatitis (AD) is a complex, chronic inflammatory skin disorder affecting more than 10% of U.K. children and is a major cause of occupation-related disability. A subset of patients, particularly those with severe AD, are persistently colonized with Staphylococcus aureus and exacerbation of disease is commonly associated with this bacterium by virtue of increased inflammation and allergic sensitization, aggravated by skin barrier defects. Understanding the complex biology of S. aureus is an important factor when developing new drugs to combat infection. Staphylococcus aureus generates exoproteins that enable invasion and dissemination within the host skin but can also damage the skin and activate the host immune system. Antibiotics are often used by dermatologists to aid clearance of S. aureus; however, these are becoming less effective and chronic usage is discouraged with the emergence of multiple antibiotic-resistant strains. New ways to target S. aureus using monoclonal antibodies and vaccines are now being developed. This review will attempt to evaluate the key biology of S. aureus, current treatment of S. aureus infections in AD and recent advances in developing new anti-S. aureus therapies that have potential in severe AD. © 2016 British Association of Dermatologists.

  6. Selective biosensing of Staphylococcus aureus using chitosan quantum dots

    Science.gov (United States)

    Abdelhamid, Hani Nasser; Wu, Hui-Fen

    2018-01-01

    Selective biosensing of Staphylococcus aureus (S. aureus) using chitosan modified quantum dots (CTS@CdS QDs) in the presence of hydrogen peroxide is reported. The method is based on the intrinsic positive catalase activity of S. aureus. CTS@CdS quantum dots provide high dispersion in aqueous media with high fluorescence emission. Staphylococcus aureus causes a selective quenching of the fluorescence emission of CTS@CdS QDs in the presence of H2O2 compared to other pathogens such as Escherichia coli and Pseudomonas aeruginosa. The intrinsic enzymatic character of S. aureus (catalase positive) offers selective and fast biosensing. The present method is highly selective for positive catalase species and requires no expensive reagents such as antibodies, aptamers or microbeads. It could be extended for other species that are positive catalase.

  7. A porcine model of haematogenous brain infectionwith staphylococcus aureus

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Agerholm, Jørgen Steen; Nielsen, Ole Lerberg

    2012-01-01

    A PORCINE MODEL OF HAEMATOGENOUS BRAIN INFECTION WITH STAPHYLOCOCCUS AUREUS Astrup Lærke1, Agerholm Jørgen1, Nielsen Ole1, Jensen Henrik1, Leifsson Páll1, Iburg Tine2. 1: Faculty of Health and Medical Sciences, University of Copenhagen, Denmark boye@life.ku.dk 2: National Veterinary Institute......, Uppsala, Sweden Introduction Staphylococcus aureus (S.aureus) is a common cause of sepsis and brain abscesses in man and a frequent cause of porcine pyaemia. Here we present a porcine model of haematogenous S. aureus-induced brain infection. Materials and Methods Four pigs had two intravenous catheters...... inserted surgically, one in a. carotis communis and one in v. jugularis externa. All pigs received 106 CFU/kg body weight S. aureus through the arterial catheter. Bacteria were either suspended in isotonic saline infused at constant flow for 60 minutes (two pigs) or given as a bolus injection of autologoue...

  8. Prevalence of mupirocin resistance among invasive coagulase-negative staphylococci and methicillin-resistant Staphylococcus aureus (MRSA) in France: emergence of a mupirocin-resistant MRSA clone harbouring mupA.

    Science.gov (United States)

    Desroches, Marine; Potier, Julien; Laurent, Frédéric; Bourrel, Anne-Sophie; Doucet-Populaire, Florence; Decousser, Jean-Winoc

    2013-08-01

    Mupirocin is the cornerstone of decolonization regimens, a successful strategy to prevent healthcare-associated staphylococcal infections. Several recent studies have reported alarming results: (i) an extending reservoir of mupA, the ancestral mobile resistance gene, among coagulase-negative staphylococci (CoNS); (ii) the emergence of a new resistance gene (mupB); and (iii) a growing number of mupirocin-resistant methicillin-resistant Staphylococcus aureus (MRSA), including highly pathogenic clones. We performed a nationwide prospective study in France to detect such trends among invasive staphylococci. Between October 2011 and February 2012, 367 MRSA and 708 CoNS invasive isolates were collected from 37 hospitals and analysed centrally. Mupirocin MICs were determined using the broth microdilution method. mupA/B PCR was performed for resistant isolates (MIC >1 mg/L). Genetic relatedness between mupirocin-resistant MRSA isolates was determined by PFGE analysis and related isolates were tested by microarray. Among MRSA isolates 2.2% (n = 8) were classified as mupirocin resistant; 1.4% (n = 5) showing low-level resistance (MIC ≤256 mg/L) and 0.8% (n = 3) high-level resistance (MIC >256 mg/L). Only the latter isolates carried mupA. A clonal relationship was identified between two mupA-negative MRSA from the same hospital and three mupA-positive MRSA from three distant towns; these three isolates belonged to the Lyon clone. Mupirocin resistance was identified in 10.3% of CoNS, mainly highly resistant mupA-positive isolates (5.6%). The mupB gene was not detected in mupirocin-resistant MRSA or CoNS. This first large national study indicates the need for thorough epidemiological monitoring and a stewardship programme to prevent and detect mupirocin resistance in staphylococci.

  9. Comparative genomic analysis of the genus Staphylococcus including Staphylococcus aureus and its newly described sister species Staphylococcus simiae

    Science.gov (United States)

    2012-01-01

    Background Staphylococcus belongs to the Gram-positive low G + C content group of the Firmicutes division of bacteria. Staphylococcus aureus is an important human and veterinary pathogen that causes a broad spectrum of diseases, and has developed important multidrug resistant forms such as methicillin-resistant S. aureus (MRSA). Staphylococcus simiae was isolated from South American squirrel monkeys in 2000, and is a coagulase-negative bacterium, closely related, and possibly the sister group, to S. aureus. Comparative genomic analyses of closely related bacteria with different phenotypes can provide information relevant to understanding adaptation to host environment and mechanisms of pathogenicity. Results We determined a Roche/454 draft genome sequence for S. simiae and included it in comparative genomic analyses with 11 other Staphylococcus species including S. aureus. A genome based phylogeny of the genus confirms that S. simiae is the sister group to S. aureus and indicates that the most basal Staphylococcus lineage is Staphylococcus pseudintermedius, followed by Staphylococcus carnosus. Given the primary niche of these two latter taxa, compared to the other species in the genus, this phylogeny suggests that human adaptation evolved after the split of S. carnosus. The two coagulase-positive species (S. aureus and S. pseudintermedius) are not phylogenetically closest but share many virulence factors exclusively, suggesting that these genes were acquired by horizontal transfer. Enrichment in genes related to mobile elements such as prophage in S. aureus relative to S. simiae suggests that pathogenesis in the S. aureus group has developed by gene gain through horizontal transfer, after the split of S. aureus and S. simiae from their common ancestor. Conclusions Comparative genomic analyses across 12 Staphylococcus species provide hypotheses about lineages in which human adaptation has taken place and contributions of horizontal transfer in pathogenesis. PMID

  10. Prevention of Healthcare Associated Staphylococcus aureus Infections

    NARCIS (Netherlands)

    L.G.M. Bode (Lonneke)

    2014-01-01

    markdownabstract__Abstract__ S. aureus colonizes the skin and mucosae of a proportion of the human population. Carriers of S. aureus are at increased risk of developing infections with this pathogen. The aim of this thesis was to add to the prevention of healthcare associated S. aureus

  11. Population structure and antimicrobial profile of Staphylococcus aureus strains associated with bovine mastitis in China.

    Science.gov (United States)

    Zhang, Lili; Li, Yuchen; Bao, Hongduo; Wei, Ruicheng; Zhou, Yan; Zhang, Hui; Wang, Ran

    2016-08-01

    Staphylococcus aureus is a significant bacterial pathogen associated with bovine mastitis. The aim of the present study was to investigate and characterize of S. aureus strains isolated from the milk of cows suffering from mastitis in the mid-east of China. Among the 200 milk samples analyzed, 58 were positive for S. aureus, of these isolates, 11 isolates were methicillin-resistant Staphylococcus aureus (MRSA). All of the 58 S. aureus strains were classified in agr group I, while seven different sequence type (ST) patterns were identified and among them the most common was ST630 followed by ST188. All of the S. aureus isolates belonging to ST630 were resistant to more than four antimicrobials, and 22.2% of isolates belonging to ST188 were resistant to eight antimicrobials. Interestingly, while strong biofilm producers demonstrated higher resistance to multiple antimicrobials, they exhibited lower intracellular survival rates. The results of this study illustrated the distribution, antimicrobial susceptibility profiles, genotype, and the ability of biofilm production and mammary epithelial cells invasion of these S. aureus isolates. This study can provide the basis for the development of a disease prevention program in dairy farms to reduce the potential risk in both animal and human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Molecular and mathematical epidemiology of Staphylococcus aureus and Streptococcus uberis mastitis in dairy herds

    NARCIS (Netherlands)

    Zadoks, Ruth Nicolet

    2002-01-01

    Mastitis is the most common and costly production disease affecting dairy cows. Staphylococcus aureus and Streptococcus uberis are two major mastitis-causing pathogens. Staphylococcus aureus is traditionally classified as contagious pathogen, while Streptococcus uberis is classified as environmental

  13. In vitro mecA gene transfer among Staphylococcus aureus in ...

    African Journals Online (AJOL)

    AJL

    2012-01-05

    resistant Staphylococcus aureus. (MRSA). INTRODUCTION. Staphylococcus aureus has been recognized as a bacterium that can cause a broad spectrum of diseases and is a major cause of hospital-acquired infections worldwide.

  14. Antimicrobial resistance of Staphylococcus aureus isolates from dairy cows and genetic diversity of resistant isolates

    Science.gov (United States)

    Staphylococcus aureus is a frequent and major contagious mastitis bacterial pathogen. The antibiotic treatment cure rates vary considerably from 4% to 92%. Staphylococcus aureus readily becomes resistant to antibiotics, resulting in persistent noncurable intramammary infection that usually results i...

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

    NARCIS (Netherlands)

    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.

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

    NARCIS (Netherlands)

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

    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

  17. One-year mortality in coagulase-negative Staphylococcus and Staphylococcus aureus infective endocarditis

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Snygg-Martin, Ulrika; Olaison, Lars

    2009-01-01

    The aim of this study was to investigate in-hospital mortality and 12-month mortality in patients with coagulase-negative Staphylococcus (CoNS) compared to Staphylococcus aureus (S. aureus) infective endocarditis (IE). We used a prospective cohort study of 66 consecutive CoNS and 170 S. aureus IE...... patients, collected at 2 tertiary university hospitals in Copenhagen (Denmark) and at 1 tertiary university hospital in Gothenburg (Sweden). Median (range) C-reactive protein at admission was higher in patients with S. aureus IE (150 mg/l (1-521) vs 94 mg/l (6-303); p...% of patients with S. aureus IE (p =0.05). In conclusion, CoNS IE was associated with a long diagnostic delay and high in-hospital mortality, whereas post-discharge prognosis was better in this group of patients compared to patients with IE due to S. aureus....

  18. Magnetic nanoparticle targeted hyperthermia of cutaneous Staphylococcus aureus infection

    Science.gov (United States)

    Kim, Min-Ho; Yamayoshi, Itsukyo; Mathew, Steven; Liln, Hubert; Nayfach, Joseph; Simon, Scott I.

    2013-01-01

    The incidence of wound infections that do not adequately respond to standard-of-care antimicrobial treatment has been increasing. To address this challenge, a novel antimicrobial magnetic thermotherapy platform has been developed in which a high-amplitude, high-frequency, alternating magnetic field (AMF) is used to rapidly heat magnetic nanoparticles that are bound to Staphylococcus aureus (S. aureus). The antimicrobial efficacy of this platform was evaluated in the treatment of both an in vitro culture model of S. aureus biofilm and a mouse model of cutaneous S. aureus infection. We demonstrated that an antibody-targeted magnetic nanoparticle bound to S. aureus was effective at thermally inactivating S. aureus and achieving accelerated wound healing without causing tissue injury. PMID:23149904

  19. Topography of distinct Staphylococcus aureus types in chronic wounds of patients with epidermolysis bullosa.

    Science.gov (United States)

    van der Kooi-Pol, Magdalena M; Sadaghian Sadabad, Mehdi; Duipmans, José C; Sabat, Artur J; Stobernack, Tim; Omansen, Till F; Westerhout-Pluister, Gerlinde N; Jonkman, Marcel F; Harmsen, Hermie J M; van Dijl, Jan Maarten

    2013-01-01

    The opportunistic pathogen Staphylococcus aureus is known to interfere with wound healing and represents a significant risk factor for wound infections and invasive disease. It is generally assumed that one individual is predominantly colonized by one S. aureus type. Nevertheless, patients with the genetic blistering disease epidermolysis bullosa (EB) often carry multiple S. aureus types. We therefore investigated whether different S. aureus types are present in individual wounds of EB patients and, if so, how they are spatially distributed. The staphylococcal topography in chronic wounds was mapped by replica-plating of used bandages and subsequent typing of S. aureus isolates. Individual chronic wounds of five patients contained up to six different S. aureus types. Unexpectedly, distinct S. aureus types formed micro-colonies that were located in close proximity and sometimes even overlapped. While some adjacent S. aureus isolates were closely related, others belonged to distinct molecular complexes. We conclude that the general assumption that one individual is predominantly colonized by one type of S. aureus does not apply to chronic wounds of EB patients. We consider this observation important, not only for EB patients, but also for other patients with chronic wounds in view of the potential risk for severe staphylococcal infections.

  20. Acute phase proteins in bovine milk in an experimental model of Staphylococcus aureus subclinical mastitis

    DEFF Research Database (Denmark)

    Eckersall, P D; Young, F J; Nolan, A M

    2006-01-01

    -SAA3 in mammary tissues was determined using immunocytochemistry. Increases of M-SAA3 and Hp in milk occurred within 12 h of Staphylococcus aureus infusion, with peak concentrations occurring 3 d after infusion of the bacteria. The increase of acute phase proteins in milk (15 h) preceded the increase......, may play a significant role in the early response to invasion of mammary tissues by pathogenic bacteria....

  1. Staphylococcus aureus sternal osteomyelitis: a rare cause of chest pain

    Directory of Open Access Journals (Sweden)

    Kaur M

    2015-10-01

    Full Text Available Chest pain is a common presenting symptom with a broad differential. Life-threatening cardiac and pulmonary etiologies of chest pain should be evaluated first. However, it is critical to perform a thorough assessment for other sources of chest pain in order to limit morbidity and mortality from less common causes. We present a rare case of a previously healthy 45 year old man who presented with focal, substernal, reproducible chest pain and Staphylococcus aureus bacteremia who was later found to have primary Staphylococcus aureus sternal osteomyelitis.

  2. Methicillin-resistant Staphylococcus aureus in a neonatal alpaca

    OpenAIRE

    Stull, Jason W.; Kenney, Daniel G.; Slavić, Durda; Weese, J. Scott

    2012-01-01

    A 6-hour-old alpaca was presented for evaluation of respiratory difficulty. As part of routine surveillance, methicillin-resistant Staphylococcus aureus (MRSA) was identified from a nasal swab taken upon admission to the hospital. No signs of MRSA infection were noted. The MRSA strain recovered was a human epidemic clone that has been associated with horses. Methicillin-resistant S. aureus colonization can occur in camelids, and the potential animal and public health risks require consideration.

  3. Photoreactivation of ultraviolet-irradiation damage in Staphylococcus aureus

    International Nuclear Information System (INIS)

    Adkins, B. Jr.; Allen, W.E.

    1982-01-01

    This study reports the capacity of Staphylococcus aureus strain 7 - 8 to undergo photoenzymatic repair of UV-irradiation induced damage and compares it to the photoreactivation (PR) response of Escherichia coli strain B. Staphylococcus aureaus showed greater inhibition by UV irradiation than E. coli, consistent with its higher adenine and thymine content of DNA. Staphylococcus aureus showed an enhanced rate of photoreactivation with no lag in initiation of the PR response at low PR doses compared to E. coli. Maximum PR capacity of both cultures was about equal and occurred in cultures incubated at 23 - 25 0 . The PR responses at 11 - 12 and 35 - 37 0 for S. aureus and E. coli differed although both were capable of PR at each of these temperatures. The PR response of E. coli was directly related to the dosage of PR light (J/m 2 ); however, the photoenzymatic capacity of S. aureus was not directly responsive to continued decrease in light intensity. The capacity of S. aureus to undergo liquid holding recovery (LHR) occurred at 23 - 25 0 (not at 11 - 12 0 or 35 - 37 0 ), whereas E. coli underwent LHR at 11 - 12 0 and 23 - 25 0 but not at 35 - 37 0 . The LHR response of S. aureus was somewhat more effective than E. coli and did not show the direct response to increased liquid-holding period as did E. coli. (author)

  4. Stilbenes reduce Staphylococcus aureus hemolysis, biofilm formation, and virulence.

    Science.gov (United States)

    Lee, Kayeon; Lee, Jin-Hyung; Ryu, Shi Yong; Cho, Moo Hwan; Lee, Jintae

    2014-09-01

    Stilbenoids have a broad range of beneficial health effects. On the other hand, the emergence of antibiotic-resistant Staphylococcus aureus presents a worldwide problem that requires new antibiotics or nonantibiotic strategies. S. aureus produces α-hemolysin (a pore-forming cytotoxin) that has been implicated in the pathogenesis of sepsis and pneumonia. Furthermore, the biofilms formed by S. aureus constitute a mechanism of antimicrobial resistance. In this study, we investigated the hemolytic and antibiofilm activities of 10 stilbene-related compounds against S. aureus. trans-Stilbene and resveratrol at 10 μg/mL were found to markedly inhibit human blood hemolysis by S. aureus, and trans-stilbene also inhibited S. aureus biofilm formation without affecting its bacterial growth. Furthermore, trans-stilbene and resveratrol attenuated S. aureus virulence in vivo in the nematode Caenorhabditis elegans, which is normally killed by S. aureus. Transcriptional analysis showed that trans-stilbene repressed the α-hemolysin hla gene and the intercellular adhesion locus (icaA and icaD) in S. aureus, and this finding was in line with observed reductions in virulence and biofilm formation. In addition, vitisin B, a stilbenoid tetramer, at 1 μg/mL was observed to significantly inhibit human blood hemolysis by S. aureus.

  5. Genetic diversity of Staphylococcus aureus in Buruli ulcer.

    Directory of Open Access Journals (Sweden)

    Nana Ama Amissah

    2015-02-01

    Full Text Available Buruli ulcer (BU is a necrotizing skin disease caused by Mycobacterium ulcerans. Previous studies have shown that wounds of BU patients are colonized with M. ulcerans and several other microorganisms, including Staphylococcus aureus, which may interfere with wound healing. The present study was therefore aimed at investigating the diversity and topography of S. aureus colonizing BU patients during treatment.We investigated the presence, diversity, and spatio-temporal distribution of S. aureus in 30 confirmed BU patients from Ghana during treatment. S. aureus was isolated from nose and wound swabs, and by replica plating of wound dressings collected bi-weekly from patients. S. aureus isolates were characterized by multiple-locus variable number tandem repeat fingerprinting (MLVF and spa-typing, and antibiotic susceptibility was tested.Nineteen (63% of the 30 BU patients tested positive for S. aureus at least once during the sampling period, yielding 407 S. aureus isolates. Detailed analysis of 91 isolates grouped these isolates into 13 MLVF clusters and 13 spa-types. Five (26% S. aureus-positive BU patients carried the same S. aureus genotype in their anterior nares and wounds. S. aureus isolates from the wounds of seven (37% patients were distributed over two different MLVF clusters. Wounds of three (16% patients were colonized with isolates belonging to two different genotypes at the same time, and five (26% patients were colonized with different S. aureus types over time. Five (17% of the 30 included BU patients tested positive for methicillin-resistant S. aureus (MRSA.The present study showed that the wounds of many BU patients were contaminated with S. aureus, and that many BU patients from the different communities carried the same S. aureus genotype during treatment. This calls for improved wound care and hygiene.

  6. Comparison of five tests for identification of Staphylococcus aureus from clinical samples

    NARCIS (Netherlands)

    A. Luijendijk (Ad); A.F. van Belkum (Alex); J.A.J.W. Kluytmans (Jan); H.A. Verbrugh (Henri)

    1996-01-01

    textabstractFive different laboratory tests for the identification of Staphylococcus aureus were compared. Analyses of 271 presumptive S. aureus strains, supplemented with 59 well-defined methicillin-resistant S. aureus (MRSA) isolates, were performed. Only the

  7. Staphylococcus aureus and the ecology of the nasal microbiome

    DEFF Research Database (Denmark)

    Liu, Cindy M; Price, Lance B; Hungate, Bruce A

    2015-01-01

    The human microbiome can play a key role in host susceptibility to pathogens, including in the nasal cavity, a site favored by Staphylococcus aureus. However, what determines our resident nasal microbiota-the host or the environment-and can interactions among nasal bacteria determine S. aureus......, their negative interactions depend on thresholds of absolute abundance. These findings demonstrate that nasal microbiota is not fixed by host genetics and opens the possibility that nasal microbiota may be manipulated to prevent or eliminate S. aureus colonization....

  8. Simple method for correct enumeration of Staphylococcus aureus

    DEFF Research Database (Denmark)

    Haaber, J.; Cohn, M. T.; Petersen, A.

    2016-01-01

    culture. When grown in such liquid cultures, the human pathogen Staphylococcus aureus is characterized by its aggregation of single cells into clusters of variable size. Here, we show that aggregation during growth in the laboratory standard medium tryptic soy broth (TSB) is common among clinical...... and laboratory S. aureus isolates and that aggregation may introduce significant bias when applying standard enumeration methods on S. aureus growing in laboratory batch cultures. We provide a simple and efficient sonication procedure, which can be applied prior to optical density measurements to give...

  9. Staphylococcus aureus: nuevos y antiguos antimicrobianos Staphylococcus aureus: new and old antimicrobial agents

    Directory of Open Access Journals (Sweden)

    B. Perazzi

    2010-09-01

    Full Text Available El objetivo del trabajo fue evaluar la sensibilidad a antiguos y nuevos antimicrobianos de aislamientos de Staphylococcus aureus resistentes a la oxacilina, de origen hospitalario (SAOR-H y adquiridos en la comunidad (SAOR-AC, y también en aislamientos sensibles a la oxacilina (SAOS. Se estudió en forma prospectiva la concentración inhibitoria mínima a diversos antimicrobianos en 118 aislamientos consecutivos por dilución seriada en agar según las indicaciones del CLSI. En los aislamientos de SAOR sin resistencia acompañante se determinó la presencia de los genes mec A, leucocidina de Panton Valentine (LPV y γ-hemolisina por PCR, y del cassette SCC mec por PCR múltiple. De los 118 aislamientos estudiados, 44 fueron SAOR-H, 16 SAOR-AC y 58 SAOS. Los aislamientos de SAOR-H presentaron resistencia simultánea a eritromicina, clindamicina, gentamicina, ciprofloxacina, levofloxacina y moxifloxacina, y todos fueron sensibles a tigeciclina (TIG, vancomicina, teicoplanina y linezolid (LZD. Los aislamientos de SAOR-AC fueron resistentes solamente a OXA y sensibles a todos los antimicrobianos ensayados. En todos ellos se detectaron los genes mec A, LPV, γ-hemolisina y el cassette SCC mec IV. En SAOS y en SAOR-AC todos los antimicrobianos no ß-lactámicos ensayados presentaron excelente actividad in vitro, mientras que en SAOR-H sólo los antiguos antimicrobianos como glucopéptidos, doxiciclina, rifampicina y trimetoprima-sulfametoxazol presentaron buena actividad in vitro, al igual que LZD y TIG entre los nuevos antimicrobianos. El fenotipo de SAOR sin resistencia acompañante fue altamente predictivo de SAOR-AC, ya que fue confirmado por presentar el cassette SCC mec IV.The objective of the study was to evaluate the susceptibility to old and new antimicrobial agents against hospital-acquired oxacillin-resistant Staphylococcus aureus (HA-ORSA, community-acquired oxacillin-resistant S. aureus (CA-ORSA, and oxacillin-susceptible S. aureus (OSSA

  10. Staphylococcus aureus vs. Osteoblast: Relationship and Consequences in Osteomyelitis

    Science.gov (United States)

    Josse, Jérôme; Velard, Frédéric; Gangloff, Sophie C.

    2015-01-01

    Bone cells, namely osteoblasts and osteoclasts work in concert and are responsible for bone extracellular matrix formation and resorption. This homeostasis is, in part, altered during infections by Staphylococcus aureus through the induction of various responses from the osteoblasts. This includes the over-production of chemokines, cytokines and growth factors, thus suggesting a role for these cells in both innate and adaptive immunity. S. aureus decreases the activity and viability of osteoblasts, by induction of apoptosis-dependent and independent mechanisms. The tight relationship between osteoclasts and osteoblasts is also modulated by S. aureus infection. The present review provides a survey of the relevant literature discussing the important aspects of S. aureus and osteoblast interaction as well as the ability for antimicrobial peptides to kill intra-osteoblastic S. aureus, hence emphasizing the necessity for new anti-infectious therapeutics. PMID:26636047

  11. Staphylococcus aureus shifts towards commensalism in response to Corynebacterium species

    Directory of Open Access Journals (Sweden)

    Matthew M Ramsey

    2016-08-01

    Full Text Available Staphylococcus aureus–human interactions result in a continuum of outcomes from commensalism to pathogenesis. S. aureus is a clinically important pathogen that asymptomatically colonizes ~25% of humans as a member of the nostril and skin microbiota, where it resides with other bacteria including commensal Corynebacterium species. Commensal Corynebacterium spp. are also positively correlated with S. aureus in chronic polymicrobial diabetic foot infections, distinct from acute monomicrobial S. aureus infections. Recent work by our lab and others indicates that microbe-microbe interactions between S. aureus and human skin/nasal commensals, including Corynebacterium species, affect S. aureus behavior and fitness. Thus, we hypothesized that S. aureus interactions with Corynebacterium spp. diminish S. aureus virulence. We tested this by assaying for changes in S. aureus gene expression during in vitro mono- versus coculture with Corynebacterium striatum, a common skin and nasal commensal. We observed a broad shift in S. aureus gene transcription during in vitro growth with C. striatum, including increased transcription of genes known to exhibit increased expression during human nasal colonization and decreased transcription of virulence genes. S. aureus uses several regulatory pathways to transition between commensal and pathogenic states. One of these, the quorum signal accessory gene regulator (agr system, was strongly inhibited in response to Corynebacterium spp. Phenotypically, S. aureus exposed to C. striatum exhibited increased adhesion to epithelial cells, reflecting a commensal state, and decreased hemolysin activity, reflecting an attenuation of virulence. Consistent with this, S. aureus displayed diminished fitness in experimental in vivo coinfection with C. striatum when compared to monoinfection. These data support a model in which S. aureus shifts from virulence towards a commensal state when exposed to commensal Corynebacterium species.

  12. Staphylococcus aureus Shifts toward Commensalism in Response to Corynebacterium Species

    Science.gov (United States)

    Ramsey, Matthew M.; Freire, Marcelo O.; Gabrilska, Rebecca A.; Rumbaugh, Kendra P.; Lemon, Katherine P.

    2016-01-01

    Staphylococcus aureus–human interactions result in a continuum of outcomes from commensalism to pathogenesis. S. aureus is a clinically important pathogen that asymptomatically colonizes ~25% of humans as a member of the nostril and skin microbiota, where it resides with other bacteria including commensal Corynebacterium species. Commensal Corynebacterium spp. are also positively correlated with S. aureus in chronic polymicrobial diabetic foot infections, distinct from acute monomicrobial S. aureus infections. Recent work by our lab and others indicates that microbe–microbe interactions between S. aureus and human skin/nasal commensals, including Corynebacterium species, affect S. aureus behavior and fitness. Thus, we hypothesized that S. aureus interactions with Corynebacterium spp. diminish S. aureus virulence. We tested this by assaying for changes in S. aureus gene expression during in vitro mono- versus coculture with Corynebacterium striatum, a common skin and nasal commensal. We observed a broad shift in S. aureus gene transcription during in vitro growth with C. striatum, including increased transcription of genes known to exhibit increased expression during human nasal colonization and decreased transcription of virulence genes. S. aureus uses several regulatory pathways to transition between commensal and pathogenic states. One of these, the quorum signal accessory gene regulator (agr) system, was strongly inhibited in response to Corynebacterium spp. Phenotypically, S. aureus exposed to C. striatum exhibited increased adhesion to epithelial cells, reflecting a commensal state, and decreased hemolysin activity, reflecting an attenuation of virulence. Consistent with this, S. aureus displayed diminished fitness in experimental in vivo coinfection with C. striatum when compared to monoinfection. These data support a model in which S. aureus shifts from virulence toward a commensal state when exposed to commensal Corynebacterium species. PMID:27582729

  13. The therapeutic effect of Chlorogenic acid against Staphylococcus aureus infection through Sortase A inhibition

    Directory of Open Access Journals (Sweden)

    Lin eWang

    2015-10-01

    Full Text Available The emergence and wide spread of multi-drug resistant Staphylococcus aureus (S. aureus requires the development of new therapeutic agents with alternative modes of action. Anti-virulence strategies are hoped to meet that need. Sortase A (SrtA has attracted great interest as a potential drug target to treat infections caused by S. aureus, as many of the surface proteins displayed by SrtA function as virulence factors by mediating bacterial adhesion to specific organ tissues, invasion of host cells, and evasion of the host-immune responses. It has been suggested that inhibitors of SrtA might be promising candidates for the treatment and/or prevention of S. aureus infections. In this study, we report that Chlorogenic acid (CHA, a natural compound that lacks significant anti–S. aureus activity, inhibit the activity of SrtA in vitro (IC50=33.86±5.55μg/ml and the binding of S. aureus to fibrinogen (Fg. Using molecular dynamics simulations and mutagenesis assays, we further demonstrate that CHA binds to the binding sites of C184 and G192 in the SrtA. In vivo studies demonstrated that CHA prevent mice from S. aureus-induced renal abscess, resulting in a significant survival advantage. These findings indicate that CHA is a promising therapeutic compound against SrtA during S. aureus infections.

  14. Staphylococcus aureus bacteriuria as a prognosticator for outcome of Staphylococcus aureus bacteremia: a case-control study

    Directory of Open Access Journals (Sweden)

    Weinstein Robert A

    2010-07-01

    Full Text Available Abstract Background When Staphylococcus aureus is isolated in urine, it is thought to usually represent hematogenous spread. Because such spread might have special clinical significance, we evaluated predictors and outcomes of S. aureus bacteriuria among patients with S. aureus bacteremia. Methods A case-control study was performed at John H. Stroger Jr. Hospital of Cook County among adult inpatients during January 2002-December 2006. Cases and controls had positive and negative urine cultures, respectively, for S. aureus, within 72 hours of positive blood culture for S. aureus. Controls were sampled randomly in a 1:4 ratio. Univariate and multivariable logistic regression analyses were done. Results Overall, 59% of patients were African-American, 12% died, 56% of infections had community-onset infections, and 58% were infected with methicillin-susceptible S. aureus (MSSA. Among 61 cases and 247 controls, predictors of S. aureus bacteriuria on multivariate analysis were urological surgery (OR = 3.4, p = 0.06 and genitourinary infection (OR = 9.2, p = 0.002. Among patients who died, there were significantly more patients with bacteriuria than among patients who survived (39% vs. 17%; p = 0.002. In multiple Cox regression analysis, death risks in bacteremic patients were bacteriuria (hazard ratio 2.9, CI 1.4-5.9, p = 0.004, bladder catheter use (2.0, 1.0-4.0, p = 0.06, and Charlson score (1.1, 1.1-1.3, p = 0.02. Neither length of stay nor methicillin-resistant Staphylococcus aureus (MRSA infection was a predictor of S. aureus bacteriuria or death. Conclusions Among patients with S. aureus bacteremia, those with S. aureus bacteriuria had 3-fold higher mortality than those without bacteriuria, even after adjustment for comorbidities. Bacteriuria may identify patients with more severe bacteremia, who are at risk of worse outcomes.

  15. Impact of oral gut decontamination on Staphylococcus aureus colonisation in patients undergoing allogeneic haematopoietic stem cell transplantation.

    Science.gov (United States)

    Wilk, C Matthias; Weber, Isabel; Seidl, Kati; Rachmühl, Carole; Holzmann-Bürgel, Anne; Müller, Antonia M S; Kuster, Stefan P; Schanz, Urs; Zinkernagel, Annelies S

    2017-12-01

    Recipients of allogeneic haematopoietic stem cell transplantation (allo-HSCT) are severely immunocompromised and are at increased risk of infection. In this prospective, observational, single-centre study including 110 allo-HSCT recipients, the rate of Staphylococcus aureus colonisation was reduced from 11.8% to 0% (P <0.001) following peritransplant oral gut decontamination. No invasive S. aureus infections were observed. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  16. A study of Staphylococcus aureus nasal carriage, antibacterial ...

    African Journals Online (AJOL)

    2014-12-30

    Dec 30, 2014 ... Aim: This study was to determine the virulence encoding genes, and the antibiotic resistance patterns of the. Staphylococcus aureus isolates, which .... Gram stain, catalase activity, tube coagulase test). All. S. aureusisolates were tested for ... with the use of lysozyme (20 mg/ml, Sigma) in the cell lysis step.

  17. Nasal carriage of Staphylococcus aureus among food handlers and ...

    African Journals Online (AJOL)

    Food handlers have been recognized to play a major role in the transmission of food borne diseases; contributing significantly to the global incidence and burden of the diseases. This study therefore, assesses the nasal carriage of staphylococcus aureus among food handlers and restaurant workers in Ekpoma, Edo State, ...

  18. Efficacy of extended cefquinome treatment of clinical Staphylococcus aureus mastitis

    NARCIS (Netherlands)

    Swinkels, J. M.; Cox, P.; Schukken, Y. H.; Lam, T. J G M|info:eu-repo/dai/nl/14686820X

    2013-01-01

    Clinical Staphylococcus aureus mastitis is difficult to cure. Extended antimicrobial treatment is often advocated as a practical approach to improve cure rates; however, scientific evidence of this hypothesis is lacking. A multi-centered, nonblinded, randomized, positive-controlled clinical trial

  19. Microstructures as IR-sensors with Staphylococcus aureus bacteria

    Science.gov (United States)

    Baikova, T. V.; Danilov, P. A.; Gonchukov, S. A.; Yermachenko, V. M.; Ionin, A. A.; Khmelnitskii, R. A.; Kudryashov, S. I.; Nguyen, T. T. H.; Rudenko, A. A.; Saraeva, I. N.; Svistunova, T. S.; Zayarny, D. A.

    2017-09-01

    Using a micro-hole grating in a supported silver film as a laser-fabricated novel optical platform for surface-enhanced IR absoprtion/reflection spectroscopy, characteristic absorption bands of Staphylococcus aureus, especially - its buried carotenoid fragments - were detected in FT-IR spectra with 10-fold analytical enhancement, paving the way to spectral express-identification of the pathogenic microorganisms.

  20. Detection and identification of Staphylococcus aureus in raw milk by ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-04-12

    Apr 12, 2010 ... bacterial pathogens, S. aureus probe, Staphylococcus spp. probe, nucleic acid fixture positive controls and positive experimental control ... bacterial pathogens by which raw milk is contaminated in most cases, can result in ... benign skin infections to life-threatening endocarditis and toxic shock syndrome ...

  1. [Staphylococcus aureus methicillin-resistant community acquired neonatal orbital cellulitis].

    Science.gov (United States)

    Pérez, M Guadalupe; Castro, Graciela; Mansilla, Celeste; Kaldzielski, Carina; Salas, Gisela; Rosanova, María Teresa; Berberian, Griselda

    2013-04-01

    Orbital cellulitis typically occurs in older children, but it can occasionally affect infants and neonates. Staphylococcus aureus is the main pathogen isolated. Outcome depends on an adequate initial approach. We report three neonates with orbital cellulitis caused by community-associated MRSA.

  2. Methicillin-resistant Staphylococcus aureus in pork production shower facilities.

    Science.gov (United States)

    Leedom Larson, Kerry R; Harper, Abby L; Hanson, Blake M; Male, Michael J; Wardyn, Shylo E; Dressler, Anne E; Wagstrom, Elizabeth A; Tendolkar, Shaliesh; Diekema, Daniel J; Donham, Kelley J; Smith, Tara C

    2011-01-01

    As methicillin-resistant Staphylococcus aureus (MRSA) has been found in pigs, we sought to determine if MRSA is present in pork production shower facilities. In two production systems tested, 3% and 26% of shower samples were positive for MRSA. spa types identified included t034, t189, t753, and t1746.

  3. Surveillance for methicillin-resistant Staphylococcus aureus in Battambang, Cambodia.

    Science.gov (United States)

    Fishbain, Joel T; Viscount, Helen B

    2002-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA) and humanitarian missions are increasing worldwide. The prevalence of MRSA in the populations served may be unknown. A BRAVA (Blast Resuscitlation and Victim Assistance) mission was conducted at Battambang, Cambodia that included microbiology support. No MRSA was detected in our patients despite the reported increase in MRSA in Asia. Continued investigation is warranted for future missions.

  4. Methicillin-Resistant Staphylococcus aureus (MRSA) carriage and ...

    African Journals Online (AJOL)

    Objectives: To determine Methicillin-Resistant Staphylococcus aureus (MRSA) carriage and antibiotic susceptibility patterns in patients admitted to critical care units in a central hospital in Harare Zimbabwe. Design: A cross sectional study of patients admitted to Critical Care Units (CCUs), to determine the ...

  5. co-occurrence of candida albicans and staphylococcus aureus in ...

    African Journals Online (AJOL)

    2014-01-31

    Jan 31, 2014 ... Mcloughlin, R.M. (2013). Staphylococcus aureus colonisation: modulation of host immune response and impact on human vaccine design. Front. Immunol.; 4:507. Cannon, R.D., Holmes, A.R., Mason, A.B. and. Monk, B.C. (1995). Oral Candida: clearance, colonization, or candidiasis? J. Dent. Res.; 74: 1152 ...

  6. Detection of some virulence factors in Staphylococcus aureus ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... region gene, 22 samples contained X region coding gene protein A, 3 sample contained Toxic shock syndrome toxin gene (tst), ..... Vandenesch F, Moghazeh S (1995). The agr P2 operon: an autocatalytic sensory transduction system in Staphylococcus aureus. Mol. Gen. Genet. 248: 446-458. Novick RP ...

  7. Prevalence of methicillin-resistant Staphylococcus aureus nasal ...

    African Journals Online (AJOL)

    Background. There is little information regarding the presence and characteristics of methicillin-resistant Staphylococcus aureus (MRSA), an important nosocomial pathogen, in rural African hospitals. Objectives. To determine the prevalence of MRSA colonisation in patients admitted to a rural hospital with tuberculosis (TB) ...

  8. An Interdisciplinary Experiment: Azo-Dye Metabolism by "Staphylococcus Aureus"

    Science.gov (United States)

    Brocklesby, Kayleigh; Smith, Robert; Sharp, Duncan

    2012-01-01

    An interdisciplinary and engaging practical is detailed which offers great versatility in the study of a qualitative and quantitative metabolism of azo-dyes by "Staphylococcus aureus". This practical has broad scope for adaptation in the number and depth of variables to allow a focused practical experiment or small research project. Azo-dyes are…

  9. A study of Staphylococcus aureus nasal carriage, antibacterial ...

    African Journals Online (AJOL)

    Aim: This study was to determine the virulence encoding genes, and the antibiotic resistance patterns of the Staphylococcus aureus isolates, which were isolated from the nasal samples of chest clinic patients. Materials and Methods: The nasal samples of the in‑patients (431) and out‑patients (1857) in Kayseri Training and ...

  10. The Pre - Eminence of Staphylococcus Aureus as The Causative ...

    African Journals Online (AJOL)

    A range of infections is caused by Staphylococcal organisms prominent among them are nosocomial superficial infections manifesting as abscesses, furuncles, and wound infections. The study objective is to determine the degree to which Staphylococcus aureus is a cause of such lesions in a tertiary health care institution ...

  11. Increased risk of arterial thromboembolic events after Staphylococcus aureus bacteremia

    DEFF Research Database (Denmark)

    Mejer, N; Gotland, N; Uhre, M L

    2015-01-01

    OBJECTIVES: An association between infection and arterial thromboembolic events (ATE) has been suggested. Here we examined the risk of myocardial infarction (MI), stroke and other ATE after Staphylococcus aureus bacteremia (SAB). METHODS: Danish register-based nation-wide observational cohort study...

  12. Antibiotic sensitivity pattern of Staphylococcus aureus from clinical ...

    African Journals Online (AJOL)

    Background: The importance of Staphylococcus aureus as a persistent nosocomial and community acquired pathogen has become a global health concern. It has a remarkable capability of evolving different mechanisms of resistance to most antimicrobial agents. The aim of the present study is to establish the incidence of ...

  13. Enterotoxicity of Staphylococcus aureus isolated from beans pudding

    African Journals Online (AJOL)

    36 samples of beans pudding from selected sources were analysed for Staphylococcus aureus and Bacillus cereus using standard protocols aimed at assessing its bacteriological quality. Samples obtained from restaurant showed slightly lower value for total plate count (1.3 x 104 - 1.6 x 106 cfu/gm) compared to samples ...

  14. Pyrazole Based Inhibitors against Enzymes of Staphylococcus aureus

    DEFF Research Database (Denmark)

    Jagadeesan, G.; Vijayakuma, Vinodhkumar; Palayam, Malathy

    2015-01-01

    agents. The current study focuses on molecular docking and dynamics studies of pyrazole derivatives against Nucleosidase and DNA gyrase B of Staphylococcus aureus. Molecular docking and dynamics studies reveal that some of these derivatives show better binding abilities than some of the current drugs...

  15. Pitfalls in the routine diagnosis of Staphylococcus aureus | Bello ...

    African Journals Online (AJOL)

    Two hundred isolates of Presumed Staphylococcus aureus from routine clinical specimens, collected from two government hospitals in Abha, Saudi Arabia, had their identity verified. We used the tube coagulase test as our gold standard. Twenty (10%) of the isolates were mis-identified. Reliance by the two laboratories on ...

  16. Methicilin-resistant Staphylococcus aureus (MRSA) at Jos University ...

    African Journals Online (AJOL)

    A prospective surveillance of Methicillin resistant staphylococcus aureus (MRSA) was carried out at Jos University Teaching Hospital, Nigeria, over a one year period. This study highlights the continuos importance of MRSA in causing both hospital and to a less extent community acquired infections. Out of the 180 ...

  17. Genetic variation and relationship in Staphylococcus aureus isolates ...

    African Journals Online (AJOL)

    ... into two major groups, the first comprises of mildly and weakly virulence, while the other group are the highly virulence Staphylococci. The results demonstrated that the RAPD technique may be of great use in the classification of Staphylococcus aureus. African Journal of Biotechnology Vol. 4 (7), pp. 611-614, 2005 ...

  18. Occurrence of Methicilin-resistant Staphylococcus aureus in a ...

    African Journals Online (AJOL)

    VO Ogunleye, AO Ogunleye, ATP Ajuwape, KA Akande, AI Adetosoye ... Taking into consideration the danger associated with methicillin resistant Staphylococcus aureus, the findings from this study underscores the need for public enlightenment of both the hospital workers and the general public on the risk associated with ...

  19. antibacterial properties of mangifera indica on staphylococcus aureus.

    African Journals Online (AJOL)

    boaz

    activity. Keywords: Staphylococcus aureus, antimicrobial activity, MIC, Phytochemical screening, MBC. INTRODUCTION. Plant derived products like gums, oils and extracts have been used for therapeutic purpose before the introduction of modern drugs (1; 2) and continues to provide health coverage for over eighty percent.

  20. Methicillin-resistant Staphylococcus aureus in Dutch soccer team.

    NARCIS (Netherlands)

    Huijsdens, Xander W; Lier, Ans M C van; Kregten, Eric van; Verhoef, Liesbeth; Santen-Verheuvel, Marga G van; Spalburg, Emile; Wannet, Wim J B

    2006-01-01

    An outbreak of community-acquired methicillin-resistant Staphylococcus aureus occurred among members and close contacts of a soccer team. Typing of the isolates showed the outbreak was caused by the well-known European ST80-IV strain. To our knowledge, this is the first report of an outbreak of this

  1. spa typing for epidemiological surveillance of Staphylococcus aureus

    NARCIS (Netherlands)

    Hallin, Marie; Friedrich, Alexander W; Struelens, Marc J; Caugant, Dominique A.

    2009-01-01

    The spa typing method is based on sequencing of the polymorphic X region of the protein A gene (spa), present in all strains of Staphylococcus aureus. The X region is constituted of a variable number of 24-bp repeats flanked by well-conserved regions. This single-locus sequence-based typing method

  2. Staphylococcus aureus in mastitic crossbreed cows and its ...

    African Journals Online (AJOL)

    The occurrence of bovine mastitis associated with Staphylococcus aureus varied significantly (p<0.05) between breed, lactation stage, parity and age. It was higher (n= 49, 56.9%) in Zebu-Jersey than Zebu-Holstein Frisian (n= 25, 37.3%) crossbred cows. Staphyloccocal mastitis is a major health problem in dairy farm of ...

  3. Incidence of staphylococcus aureus in locally produced fresh milk ...

    African Journals Online (AJOL)

    This paper investigates the incidence of the bacterial organism Staphylococcus, aureus in locally produced fresh milk (nono). The fresh milk was obtained from the Damaturu main market, Yobe state of Nigeria. Petri dishes were washed and allowed to dry. They were then sterilized in hot air oven at 130°C for two hours and ...

  4. Prevalence of methicillin-resistant Staphylococcus aureus (MRSA ...

    African Journals Online (AJOL)

    One of each duplicate swab sample was inoculated directly onto chocolate agar, incubated for 24 hours at 37oc while the other swab was used to make a smear for Gram staining. All isolates were identified using standard microbiological methods. Staphylococcus aureus isolates were screened for methicillin resistance ...

  5. Psoriasis and staphylococcus aureus skin colonization in Moroccan ...

    African Journals Online (AJOL)

    Psoriatic lesions are rarely complicated by recurrent infections. The aim of our study is to determine skin colonisation and nasal carriage of Staphylococcus aureus in patients with psoriasis and in healthy persons. Patients and methods: a comparative study that include 33 patients with psoriasis and 33 healthy persons.

  6. Prevalence of methicillin-resistant Staphylococcus aureus and ...

    African Journals Online (AJOL)

    Wound colonization by microorganisms is most frequently polymicrobial and incidences of high level resistance among bacterial isolates from wounds have been reported. Methicillin-resistant Staphylococcus aureus (MRSA) and extendedspectrum beta-lactamase (ESBL) producing Gram-negative bacteria both constitute ...

  7. Methicillin resistance in Staphylococcus aureus : a review of the ...

    African Journals Online (AJOL)

    Methicillin resistance in Staphylococcus aureus : a review of the molecular epidemiology, clinical significance and laboratory detection methods. ... Added to this burden is the emergence of more virulent strains of community-associated MRSA (CAMRSA) which at the turn of the century, has been increasingly reported to ...

  8. Methicillin-resistant Staphylococcus aureus isolates from Iranian ...

    African Journals Online (AJOL)

    Methicillin-resistant Staphylococcus aureus isolates from Iranian restaurant food samples: Panton-Valentine Leukocidin, SCCmec phenotypes and antimicrobial resistance. ... TetK (80.72 %), linA (67.46 %), aadA1 (62.65 %), and msrA (55.42 %) were the most frequently identified resistance genes. SCCmec V (57.83%) ...

  9. Methicillin-resistant Staphylococcus aureus in Pig Farming

    OpenAIRE

    Voss, Andreas; Loeffen, Frans; Bakker, Judith; Klaassen, Corne; Wulf, Mireille

    2005-01-01

    We conducted a study among a group of 26 regional pig farmers to determine the methicillin-resistant Staphylococcus aureus prevalence rate and found it was >760 times greater than the rate of patients admitted to Dutch hospitals. While spa-type t108 is apparently a more widespread clone among pig farmers and their environment, we did find other spa-types.

  10. Transmission of methicillin-resistant Staphylococcus aureus to household contacts

    NARCIS (Netherlands)

    F.P.N. Mollema (Femke); J.H. Richardus (Jan Hendrik); M.D. Behrendt (Myra); N. Vaessen (Norbert); W. Lodder; W. Hendriks; H.A. Verbrugh (Henri); A. Voss (Andreas)

    2010-01-01

    textabstractThe frequency of and risk factors for methicillin-resistant Staphylococcus aureus (MRSA) transmission from a MRSA index person to household contacts were assessed in this prospective study. Between January 2005 and December 2007, 62 newly diagnosed MRSA index persons (46 patients and 16

  11. Staphylococcus aureus in mastitic crossbreed cows and its ...

    African Journals Online (AJOL)

    A cross sectional study was conducted in dairy farms of Addis Ababa city from. November 2011 to April 2012 to estimate the prevalence of Staphylococcus aureus and its associated risk factors in mastitic dairy cows. Milk samples were collected from 153 (50 clinical and 103 subclinical) mastitic lactating crossbred cows and.

  12. Multiple drug resistance Staphylococcus aureus isolated in foods of ...

    African Journals Online (AJOL)

    Background: StaphylococcuS. aureus is the most important agent, which is known to cause a wide range of diseases in both human and animals. Extended use and misuse of antibiotics in agriculture, stock farming and in the treatment of human diseases, has contributed to the rapid increase of the number of bacteria that ...

  13. Antibiotic sensitivity pattern of Staphylococcus aureus from clinical

    African Journals Online (AJOL)

    raoul

    2011-01-26

    Jan 26, 2011 ... Table 3 shows the antibiotic sensitivity and resistance pattern of Staphylococcus aureus to various antibiotics. The highest frequency of sensitivity was observed with Levofloxacin 150(100%) followed by Ciprofloxacin 90(78.9%). The least was observed with Penicillin 6(7.1%). The number of strains tested ...

  14. Survival of Esherichia coli 0157:H7, Staphylococcus aureus ...

    African Journals Online (AJOL)

    The survival or inhibition of foodborne pathogens in different fermented products are well documented. This prompted the study to evaluate survival of Esherichia coli O157:H7, Staphylococcus aureus, Shigella flexneri and Salmonella spp. in two Ethiopian traditional fermented low-alcohol beverages, Shamita and Borde.

  15. Evaluation of approaches to monitor Staphylococcus aureus virulence factor expression during human disease.

    Directory of Open Access Journals (Sweden)

    Wouter Rozemeijer

    Full Text Available Staphylococcus aureus is a versatile pathogen of medical significance, using multiple virulence factors to cause disease. A prophylactic S. aureus 4-antigen (SA4Ag vaccine comprising capsular polysaccharide (types 5 and 8 conjugates, clumping factor A (ClfA and manganese transporter C (MntC is under development. This study was designed to characterize S. aureus isolates recovered from infected patients and also to investigate approaches for examining expression of S. aureus vaccine candidates and the host response during human infection. Confirmation of antigen expression in different disease states is important to support the inclusion of these antigens in a prophylactic vaccine. Hospitalized patients with diagnosed S. aureus wound (27 or bloodstream (24 infections were enrolled. Invasive and nasal carriage S. aureus isolates were recovered and characterized for genotypic diversity. S. aureus antigen expression was evaluated directly by real-time, quantitative, reverse-transcriptase PCR (qRT-PCR analysis and indirectly by serology using a competitive Luminex immunoassay. Study isolates were genotypically diverse and all had the genes encoding the antigens present in the SA4Ag vaccine. S. aureus nasal carriage was detected in 55% of patients, and in those subjects 64% of the carriage isolates matched the invasive strain. In swab samples with detectable S. aureus triosephosphate isomerase housekeeping gene expression, RNA transcripts encoding the S. aureus virulence factors ClfA, MntC, and capsule polysaccharide were detected by qRT-PCR. Antigen expression was indirectly confirmed by increases in antibody titer during the course of infection from acute to convalescent phase. Demonstration of bacterial transcript expression together with immunological response to the SA4Ag antigens in a clinically relevant patient population provides support for inclusion of these antigens in a prophylactic vaccine.

  16. Clinical implications of methicillin-resistant Staphylococcus aureus in pregnancy.

    Science.gov (United States)

    Beigi, Richard H

    2011-04-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has become an increasingly aggressive and prevalent pathogen in medicine. This pattern has also been noted in obstetrics. This review will delineate the epidemiology and clinical implications of MRSA during pregnancy. Investigations have focused on prevalence of MRSA colonization in obstetrics and the associated morbidity. In addition, some attention has been focused on the neonatal implications of maternal colonization. Overall, the rates of maternal MRSA colonization noted in the United States have been low, in the range of 0.5-4%. The clinical impact of MRSA colonization among pregnant women has also been estimated to be modest. Roughly 357 invasive MRSA infections per 100,000 live births in the United States occur on an annual basis. It is however important to note that published estimates likely underestimate the full scope of MRSA in pregnancy given the lack of formal reporting, importance of related neonatal colonization and morbidity, the complicated treatment implications in pregnant women, the recognized high pathogenicity of MRSA infections, and propensity for recurrent infections among community-acquired MRSA strains. MRSA is an increasingly important pathogen in modern healthcare and in the obstetric population. Continued surveillance and research remains a top priority.

  17. Proportions of Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus in Patients with Surgical Site Infections in Mainland China: A Systematic Review and Meta-Analysis

    OpenAIRE

    Yang, Zhirong; Wang, Jing; Wang, Weiwei; Zhang, Yuelun; Han, Lizhong; Zhang, Yuan; Nie, Xiaolu; Zhan, Siyan

    2015-01-01

    Background Sufficient details have not been specified for the epidemiological characteristics of Staphylococcus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA) among surgical site infections (SSIs) in mainland China. This systematic review aimed to estimate proportions of S. aureus and MRSA in SSIs through available published studies. Methods PubMed, Embase and four Chinese electronic databases were searched to identify relevant primary studies published between 2007...

  18. Incidence, trends and demographics of Staphylococcus aureus infections in Auckland, New Zealand, 2001–2011

    Science.gov (United States)

    2013-01-01

    Background New Zealand has a higher incidence of Staphylococcus aureus disease than other developed countries, with significant sociodemographic variation in incidence rates. In contrast to North America, the majority of disease is due to methicillin-susceptible S. aureus (MSSA), although relatively little is known about the comparative demographics of MSSA and methicillin-resistant S. aureus (MRSA) infections in New Zealand. Methods Our objectives were to describe the trends, incidence and patient demographics of all S. aureus infections in patients presenting to our institution between 2001 and 2011, and compare the epidemiology of MSSA and MRSA infections. We identified all patients with S. aureus infections over the study period. A unique S. aureus infection was defined as the first positive S. aureus culture taken from the same patient within a thirty-day period. Standard definitions were used to classify episodes into community- or healthcare-associated S. aureus infection. Results There were 16,249 S. aureus infections over the study period. The incidence increased significantly over the study period from 360 to 412 per 100,000 population (P < 0.001), largely driven by an increase in community-associated non-invasive MSSA infections. When compared with MSSA infections, patients with non-multiresistant MRSA infections were more likely to be older, have hospital-onset infections and be Māori or Pacific Peoples. Conclusions Our work provides valuable baseline data on the epidemiology and trends of S. aureus infections in New Zealand. The significant increase in community-associated S. aureus infections is of public health importance. Future studies should investigate the reasons underlying this concerning trend. PMID:24299298

  19. Staphylococcus aureus strategies to evade the host acquired immune response.

    Science.gov (United States)

    Goldmann, Oliver; Medina, Eva

    2017-09-15

    Staphylococcus aureus poses a significant public-health problem. Infection caused by S. aureus can manifest as acute or long-lasting persistent diseases that are often refractory to antibiotic and are associated with significant morbidity and mortality. To develop more effective strategies for preventing or treating these infections, it is crucial to understand why the immune response is incapable to eradicate the bacterium. When S. aureus first infect the host, there is a robust activation of the host innate immune responses. Generally, S. aureus can survive this initial interaction due to the expression of a wide array of virulence factors that interfere with the host innate immune defenses. After this initial interaction the acquired immune response is the arm of the host defenses that will try to clear the pathogen. However, S. aureus is capable of maintaining infection in the host even in the presence of a robust antigen-specific immune response. Thus, understanding the mechanisms underlying the ability of S. aureus to escape immune surveillance by the acquired immune response will help uncover potentially important targets for the development of immune-based adjunctive therapies and more efficient vaccines. There are several lines of evidence that lead us to believe that S. aureus can directly or indirectly disable the acquired immune response. This review will discuss the different immune evasion strategies used by S. aureus to modulate the different components of the acquired immune defenses. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Beta-lactamase detection in Staphylococcus aureus and coagulase-negative Staphylococcus isolated from bovine mastitis

    Directory of Open Access Journals (Sweden)

    Bruno F. Robles

    2014-04-01

    Full Text Available The objectives of the study were to evaluate the presence/production of beta-lactamases by both phenotypic and genotypic methods, verify whether results are dependent of bacteria type (Staphylococcus aureus versus coagulase-negative Staphylococcus - CNS and verify the agreement between tests. A total of 200 bacteria samples from 21 different herds were enrolled, being 100 CNS and 100 S. aureus. Beta-lactamase presence/detection was performed by different tests (PCR, clover leaf test - CLT, Nitrocefin disk, and in vitro resistance to penicillin. Results of all tests were not dependent of bacteria type (CNS or S. aureus. Several S. aureus beta-lactamase producing isolates were from the same herd. Phenotypic tests excluding in vitro resistance to penicillin showed a strong association measured by the kappa coefficient for both bacteria species. Nitrocefin and CLT are more reliable tests for detecting beta-lactamase production in staphylococci.

  1. A porcine model of haematogenous brain infectionwith staphylococcus aureus

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Agerholm, Jørgen Steen; Nielsen, Ole Lerberg

    2012-01-01

    thromboemboli (two pigs). The venous catheter was used for blood sampling before, during and after inoculation. The pigs were euthanized either 24 or 48 hours after inoculation. The brains were collected and examined histologically. Results We describe unifocal suppurative encephalitis 48 hours after......, Uppsala, Sweden Introduction Staphylococcus aureus (S.aureus) is a common cause of sepsis and brain abscesses in man and a frequent cause of porcine pyaemia. Here we present a porcine model of haematogenous S. aureus-induced brain infection. Materials and Methods Four pigs had two intravenous catheters...... inserted surgically, one in a. carotis communis and one in v. jugularis externa. All pigs received 106 CFU/kg body weight S. aureus through the arterial catheter. Bacteria were either suspended in isotonic saline infused at constant flow for 60 minutes (two pigs) or given as a bolus injection of autologoue...

  2. Truncated Autoinducing Peptide Conjugates Selectively Recognize and Kill Staphylococcus aureus.

    Science.gov (United States)

    Tsuchikama, Kyoji; Shimamoto, Yasuhiro; Anami, Yasuaki

    2017-06-09

    The accessory gene regulator (agr) of Staphylococcus aureus coordinates various pathogenic events and is recognized as a promising therapeutic target for virulence control. S. aureus utilizes autoinducing peptides (AIPs), cyclic-peptide signaling molecules, to mediate the agr system. Despite the high potency of synthetic AIP analogues in agr inhibition, the potential of AIP molecules as a delivery vehicle for antibacterial agents remains unexplored. Herein, we report that truncated AIP scaffolds can be fused with fluorophore and cytotoxic photosensitizer molecules without compromising their high agr inhibitory activity, binding affinity to the receptor AgrC, or cell specificity. Strikingly, a photosensitizer-AIP conjugate exhibited 16-fold greater efficacy in a S. aureus cell-killing assay than a nontargeting analogue. These findings highlight the potential of truncated AIP conjugates as useful chemical tools for in-depth biological studies and as effective anti-S. aureus agents.

  3. Nickel allergy and relationship with Staphylococcus aureus in atopic dermatitis

    DEFF Research Database (Denmark)

    Anna, Bogdali M.; Grazyna, Antoszczyk; Wojciech, Dyga

    2016-01-01

    Background: The increase of nickel air pollution is supposed to frequent side effects of nickel action related to virulence potential of Staphylococcus aureus in patients with nickel allergy in atopic dermatitis. The goal was to investigate the relationship between nickel allergy and infection by S....... aureus in atopic dermatitis. Methods: Nickel allergy was confirmed in atopic patients and excluded in healthy volunteers using patch testing. Infection by S. aureus was tested in atopic patients and healthy volunteers by use of API Staph system. The specific IgE for staphylococcal enterotoxin A and B...... were measured. Secretion of IFN-g, IL-2, IL-13 by PBMC under nickel sulfate and the enterotoxins A and B stimulations were studied with ELISpot. Results: We found the increased number of infections by S. aureus in atopic patients with nickel allergy in comparison to atopic patients and healthy...

  4. Intracellular Staphylococcus aureus: Live-in and let die

    Directory of Open Access Journals (Sweden)

    Martin eFraunholz

    2012-04-01

    Full Text Available Staphylococcus aureus uses a plethora of virulence factors to accomodate a diversity of niches in its human host. Aside from the classical manifestations of S. aureus-induced diseases, the pathogen also invades and survives within mammalian host cells. The survival strategies of the pathogen are as diverse as strains or host cell types used. S. aureus is able to replicate in the phagosome or freely in the cytoplasm of its host cells. It escapes the phagosome of professional and non-professional phagocytes, subverts autophagy, induces cell death mechanisms such as apoptosis and pyronecrosis, and even can induce anti-apoptotic programs in phagocytes. The focus of this review is to present a guide to recent research outlining the variety of intracellular fates of S. aureus.

  5. Incidence, Risk Factors, and Outcomes of Panton-Valentine Leukocidin-Positive Methicillin-Susceptible Staphylococcus aureus Infections in Auckland, New Zealand ▿

    OpenAIRE

    Muttaiyah, S.; Coombs, G.; Pandey, S.; Reed, P.; Ritchie, S.; Lennon, D.; Roberts, S.

    2010-01-01

    Panton-Valentine leukocidin (PVL) has been linked to invasive community-acquired methicillin-resistant Staphylococcus aureus infections. However, the association between disease and PVL-positive methicillin-susceptible Staphylococcus aureus (MSSA) has not been widely reported. We aimed to examine the epidemiology of PVL in clinical MSSA isolates from patients presenting to Auckland City Hospital. Four hundred eleven MSSA clinical isolates and 93 nasal carriage isolates were collected and test...

  6. Polyclonal antibodies production against Staphylococcus aureus ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... why the detection and the counting of S. aureus or of the. Staphylococuses with a positive coagulase, keep their interest in alimentary microbiology and the enterotoxins staphylococcies dried dosage remains the unique means to define the food innocuousness. The standard methods of cultivation used to ...

  7. Misidentification of methicillinresistant Staphylococcus aureus (MRSA)

    African Journals Online (AJOL)

    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 ...

  8. OCCURRENCE AND ANTIBIOGRAM OF Staphylococcus aureus IN ...

    African Journals Online (AJOL)

    User

    ABSTRACT. A total of 160 dairy products comprising of 80 each of fresh milk and 'Nono' (Fermented and defatted) were collected. The samples were cultured and identified by routine bacteriological methods. Prevalence of S.aureus (8.75%) in the products was; for fresh milk 3.75% and 'Nono'. 5%. The susceptibility profile ...

  9. Resistance patterns of Staphylococcus aureus and Pseudomonas ...

    African Journals Online (AJOL)

    Two hundred (200) strains of S. aureus and P. aeruginosa were isolated from clinical samples collected from patients in Murtala Muhammad Specialist Hospital and Infectious Diseases Hospital, Kano. The confirmed isolates were tested for resistance to quinolones by the agar disk diffusion susceptibility test and the agar ...

  10. Human Staphylococcus aureus lineages among Zoological Park ...

    African Journals Online (AJOL)

    The genes mecA, mecC, lukF/lukS-PV (encoding Panton- Valentine leukocidin, PVL) and tst (toxic shock syndrome toxin-1) were investigated by PCR. Clones were defined by Multilocus Sequence Typing (MLST), spa type and Pulsed-Field Gel Electrophoresis (PFGE). Seven S. aureus isolates were recovered from four ...

  11. Characterization of Staphylococcus aureus nasal colonization rates ...

    African Journals Online (AJOL)

    Methicillin-resistant S. aureus (MRSA) colonization was 9% and it was only isolated from clinical students and HCWs. Antimicrobial susceptibility testing showed that 90.5% of the 63 strains isolated from all volunteers were ampicillin resistant. Three multi-resistant strains to three antibiotics or more were identified; two from ...

  12. Epic Immune Battles of History: Neutrophils vs. Staphylococcus aureus

    Science.gov (United States)

    Guerra, Fermin E.; Borgogna, Timothy R.; Patel, Delisha M.; Sward, Eli W.; Voyich, Jovanka M.

    2017-01-01

    Neutrophils are the most abundant leukocytes in human blood and the first line of defense after bacteria have breached the epithelial barriers. After migration to a site of infection, neutrophils engage and expose invading microorganisms to antimicrobial peptides and proteins, as well as reactive oxygen species, as part of their bactericidal arsenal. Ideally, neutrophils ingest bacteria to prevent damage to surrounding cells and tissues, kill invading microorganisms with antimicrobial mechanisms, undergo programmed cell death to minimize inflammation, and are cleared away by macrophages. Staphylococcus aureus (S. aureus) is a prevalent Gram-positive bacterium that is a common commensal and causes a wide range of diseases from skin infections to endocarditis. Since its discovery, S. aureus has been a formidable neutrophil foe that has challenged the efficacy of this professional assassin. Indeed, proper clearance of S. aureus by neutrophils is essential to positive infection outcome, and S. aureus has developed mechanisms to evade neutrophil killing. Herein, we will review mechanisms used by S. aureus to modulate and evade neutrophil bactericidal mechanisms including priming, activation, chemotaxis, production of reactive oxygen species, and resolution of infection. We will also highlight how S. aureus uses sensory/regulatory systems to tailor production of virulence factors specifically to the triggering signal, e.g., neutrophils and defensins. To conclude, we will provide an overview of therapeutic approaches that may potentially enhance neutrophil antimicrobial functions. PMID:28713774

  13. Molecular typing of antibiotic-resistant Staphylococcus aureus in Nigeria.

    Science.gov (United States)

    O'Malley, S M; Emele, F E; Nwaokorie, F O; Idika, N; Umeizudike, A K; Emeka-Nwabunnia, I; Hanson, B M; Nair, R; Wardyn, S E; Smith, T C

    2015-01-01

    Antibiotic-resistant Staphylococcus aureus including methicillin-resistant strains (MRSA) are a major concern in densely populated urban areas. Initial studies of S. aureus in Nigeria indicated existence of antibiotic-resistant S. aureus strains in clinical and community settings. 73 biological samples (40 throat, 23 nasal, 10 wound) were collected from patients and healthcare workers in three populations in Nigeria: Lagos University Teaching Hospital, Nigerian Institute of Medical Research, and Owerri General Hospital. S. aureus was isolated from 38 of 73 samples (52%). Of the 38 S. aureus samples, 9 (24%) carried the Panton-Valentine leukocidin gene (PVL) while 16 (42%) possessed methicillin resistance genes (mecA). Antibiotic susceptibility profiles indicated resistance to several broad-spectrum antibiotics. Antibiotic-resistant S. aureus isolates were recovered from clinical and community settings in Nigeria. Insight about S. aureus in Nigeria may be used to improve antibiotic prescription methods and minimize the spread of antibiotic-resistant organisms in highly populated urban communities similar to Lagos, Nigeria. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  14. Silver nanoparticles for the inhibition of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Ortiz-Gila

    2015-01-01

    Full Text Available Existe un gran ecosistema microbiano en la cavidad oral donde Staphylococcus aureus ( S. aureus se puede encontrar, causando patologías orales tales como quelitis angular, las paperas y la mucositis estafilocócica. Estas enfermedades producidas por S. aureus en la cavidad oral son consecuencia de los factores de virulencia, toxinas y multiresistencia a los antibióticos, lo que contribuye a la infección. La colonización en la cavidad oral por S. aureus en pacientes sanos es de 24% a 36%. Sin embargo, la incidencia aumenta a 48% en pacientes con prótesis debido a la formación de biofilms en la superficie de las dentaduras postizas. Actualmente, no existe ningún tratamiento para infecciones orales sin el uso de antibióticos. Investigaciones recientes indican que las nanopartículas de plata (AgNPs son un material o estrategia para eliminar S. aureus debido a su efecto antibacteriano. Sin embargo, el mecanismo del efecto inhibidor de los iones de Ag sobre S. aureus es sólo parcialmente conocida y muy poco se ha informado. Por lo tanto, el propósito de la presente revisión sistemática es determinar las estrategias y retos de la utilización de biomateriales antimicrobianos con AgNPs frente a las infecciones orales de S. aureus.

  15. The changing epidemiology of Staphylococcus aureus bloodstream infection

    DEFF Research Database (Denmark)

    Laupland, K.B.; Lyytikäinen, O.; Søgaard, Mette

    2013-01-01

    Clin Microbiol Infect ABSTRACT: Although the epidemiology of Staphylococcus aureus bloodstream infection (BSI) has been changing, international comparisons are lacking. We sought to determine the incidence of S. aureus BSI and assess trends over time and by region. Population-based surveillance...... episodes of S. aureus BSI were identified. The overall annual incidence rate for S. aureus BSI was 26.1 per 100 000 population, and those for methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) were 24.2 and 1.9 per 100 000, respectively. Although the overall incidence...... of community-onset MSSA BSI (15.0 per 100 000) was relatively similar across regions, the incidence rates of hospital-onset MSSA (9.2 per 100 000), community-onset MRSA (1.0 per 100 000) and hospital-onset MRSA (0.8 per 100 000) BSI varied substantially. Whereas the overall incidence of S. aureus BSI did...

  16. Staphylococcus aureus isolated from tonsillectomized adult patients with recurrent tonsillitis.

    Science.gov (United States)

    Katkowska, Marta; Garbacz, Katarzyna; Stromkowski, Józef

    2017-01-01

    The aim of this study was to analyze the prevalence and antibiotic resistance of Staphylococcus aureus strains from 118 tonsillectomized adults due to recurrent tonsillitis (RT). The study included strains isolated from the tonsillar surface prior to tonsillectomy, recovered from the tonsillar core at the time of surgery, and from the posterior throat 2-4 weeks after the procedure. Susceptibility of isolates to 19 antibiotics was tested in line with the Clinical and Laboratory Standards Institute recommendations. Irrespective of the stage, the most commonly isolated bacteria were gram-positive cocci, and among them S. aureus. The tonsillar core was the most common site of S. aureus isolation (30.5%), followed by the tonsillar surface (10.8%) and the posterior pharynx (5.9%). This difference turned out to be statistically significant (p Staphylococcus aureus seems to be the most common pathogen isolated from patients tonsillectomized due to RT. Staphylococcal isolates associated with RT are present mostly within the tonsillar core and susceptible to most antibiotics. They are typically isolated from patients between 21 and 30 years of age. Tonsillectomy results in less frequent isolation of S. aureus strains. © 2016 APMIS. Published by John Wiley & Sons Ltd.

  17. Staphylococcus aureus screening and decolonization in orthopaedic surgery and reduction of surgical site infections.

    Science.gov (United States)

    Chen, Antonia F; Wessel, Charles B; Rao, Nalini

    2013-07-01

    Staphylococcus aureus is the most common organism responsible for orthopaedic surgical site infections (SSIs). Patients who are carriers for methicillin-sensitive S. aureus or methicillin-resistant S. aureus (MRSA) have a higher likelihood of having invasive S. aureus infections. Although some have advocated screening for S. aureus and decolonizing it is unclear whether these efforts reduce SSIs. The purposes of this study were to determine (1) whether S. aureus screening and decolonization reduce SSIs in orthopaedic patients and (2) if implementing this protocol is cost-effective. Studies for this systematic review were identified by searching PubMed, which includes MEDLINE (1946-present), EMBASE.com (1974-present), and the Cochrane Library's (John Wiley & Sons) Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database (HTAD), and the NHS Economic Evaluation Database (NHSEED). Comprehensive literature searches were developed using EMTREE, MeSH, and keywords for each of the search concepts of decolonization, MRSA, and orthopedics/orthopedic surgery. Studies published before 1968 were excluded. We analyzed 19 studies examining the ability of the decolonization protocol to reduce SSIs and 10 studies detailing the cost-effectiveness of S. aureus screening and decolonization. All 19 studies showed a reduction in SSIs or wound complications by instituting a S. aureus screening and decolonization protocol in elective orthopaedic (total joints, spine, and sports) and trauma patients. The S. aureus screening and decolonization protocol also saved costs in orthopaedic patients when comparing the costs of screening and decolonization with the reduction of SSIs. Preoperative screening and decolonization of S. aureus in orthopaedic patients is a cost-effective means to reduce SSIs. Level IV, systematic review of Level I-IV studies. See the

  18. Capturing of staphylococcus aureus onto an interface containing graft chains

    International Nuclear Information System (INIS)

    Lee, W.; Furusaki, Shintaro; Saito, Kyoichi; Sugo, Takanobu; Makuuchi, Keizo.

    1995-01-01

    A microbial-cell-capturing material was prepared by radiation-induced grafting of glycidyl methacrylate onto a polyethylene-based fiber before the introduction of diethylamine. The prepared fiber was tested against a Staphylococcus aureus and Escherichia coli solution. The results showed that the grafted-type fiber had a capturing rate constant 1000-fold higher than the commercial crosslinked-type bead for S. aureus and that an activation energy of 39 kJ/mol was obtained for the microbial-cell-capturing action. (author)

  19. Multidrug efflux pumps in Staphylococcus aureus and their clinical implications.

    Science.gov (United States)

    Jang, Soojin

    2016-01-01

    Antibiotic resistance is rapidly spreading among bacteria such as Staphylococcus aureus, an opportunistic bacterial pathogen that causes a variety of diseases in humans. For the last two decades, bacterial multidrug efflux pumps have drawn attention due to their potential association with clinical multidrug resistance. Numerous researchers have demonstrated efflux-mediated resistance in vitro and in vivo and found novel multidrug transporters using advanced genomic information about bacteria. This article aims to provide a concise summary of multidrug efflux pumps and their important clinical implications, focusing on recent findings concerning S. aureus efflux pumps.

  20. Substituted dihydronaphthalenes as efflux pump inhibitors of Staphylococcus aureus

    DEFF Research Database (Denmark)

    Thota, Niranjan; Reddy, Mallepally V; Kumar, Ashwani

    2010-01-01

    A new series of 3-(substituted-3,4-dihydronaphthyl)-2-propenoic acid amides has been prepared through convergent synthetic strategies and tested in combination with ciprofloxacin against NorA overexpressing Staphylococcus aureus 1199B as test strain for potentiating of the drug activity. Out of 24...... compounds evaluated, 12 compounds potentiated the activity of ciprofloxacin and resulted in 2-16 fold reduction in the MIC (4-0.5 microg/mL) of the drug. The failure of these efflux pump inhibitors (EPIs) to potentiate the activity of ciprofloxacin when tested against NorA knock out S. aureus SA-K1758...

  1. Brain infection following experimental Staphylococcus aureus sepsis in pigs

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Iburg, Tine Moesgaard; Nielsen, Ole Lerberg

    2010-01-01

    Introduction: Sepsis is a major problem in humans and both the incidence and mortality is increasing. Multiple microabcesses can be found in the brain of septic patients. Staphylococcus aureus is one of the most common causes of sepsis and brain abscesses. S. aureus is also a frequent cause...... pigs were kept as controls. The pigs were euthanized in groups of four at either 6, 12, 24 or 48 h post infection. The brain was collected from all the animals and examined histologically. Results: All the inoculated pigs developed sepsis and 7 out of 12 animals had microabscesses in the prosencephalon...

  2. Sensitivity test of staphylococcus aureus against extract tinospora crispa

    OpenAIRE

    Lucia Ratna Winata Muslimin

    2017-01-01

    A bacterium such as Staphylococcus aureus ( S.aureus) produces a kind of toxic protein which can disrupt intestinal wall. Livestock reacts to these toxins by pumping lots of water into the intestine in order to rinse or flush these toxins. As a result, the livestock have diarrhea as a body response to remove the toxin in the digestive system. In the presence of these problems, farmers take a measure such as using antibiotics freely. Among farmers, antibiotics are often used freely without kn...

  3. Is methicillin-resistant Staphylococcus aureus replacing methicillin-susceptible S. aureus?

    Science.gov (United States)

    Mostofsky, Elizabeth; Lipsitch, Marc; Regev-Yochay, Gili

    2011-01-01

    Despite extensive research on the emergence of and treatments for methicillin-resistant Staphylococcus aureus (MRSA), prior studies have not rigorously evaluated the impact of methicillin resistance on the overall incidence of S. aureus infections. Yet, there are direct clinical and research implications of determining whether methicillin-susceptible S. aureus (MSSA) infection rates remain stable in the face of increasing MRSA prevalence or whether MSSA will be replaced over time. A synthesis of prior studies indicates that the emergence of healthcare-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) has led to an increase in the overall incidence of S. aureus infections, with MRSA principally adding to, rather than replacing, MSSA. However, colonization with CA-MRSA may at least partially replace colonization with MSSA. So far, evidence indicates that MSSA still accounts for many infections. Therefore, eradication of MRSA alone is not sufficient to address the public health burden of S. aureus. PMID:21737459

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

    DEFF Research Database (Denmark)

    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...

  5. Evaluation of Two New Chromogenic Media, CHROMagar MRSA and S. aureus ID, for Identifying Staphylococcus aureus and Screening Methicillin-Resistant S. aureus

    OpenAIRE

    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.

  6. Protective activity of the CnaBE3 domain conserved among Staphylococcus aureus Sdr proteins.

    Science.gov (United States)

    Becherelli, Marco; Prachi, Prachi; Viciani, Elisa; Biagini, Massimiliano; Fiaschi, Luigi; Chiarot, Emiliano; Nosari, Sarah; Brettoni, Cecilia; Marchi, Sara; Biancucci, Marco; Fontana, Maria Rita; Montagnani, Francesca; Bagnoli, Fabio; Barocchi, Michèle A; Manetti, Andrea G O

    2013-01-01

    Staphylococcus aureus is an opportunistic pathogen, commensal of the human skin and nares, but also responsible for invasive nosocomial as well as community acquired infections. Staphylococcus aureus adheres to the host tissues by means of surface adhesins, such as SdrC, SdrD, and SdrE proteins. The Sdr family of proteins together with a functional A domain, contain respectively two, three or five repeated sequences called B motifs which comprise the CnaB domains. SdrD and SdrE proteins were reported to be protective in animal models against invasive diseases or lethal challenge with human clinical S. aureus isolates. In this study we identified a 126 amino acid sequence containing a CnaB domain, conserved among the three Sdr proteins. The three fragments defined here as CnaBC2, D5 and E3 domains even though belonging to phylogenetically distinct strains, displayed high sequence similarity. Based on the sequence conservation data, we selected the CnaBE3 domain for further analysis and characterization. Polyclonal antibodies raised against the recombinant CnaBE3 domain recognized SdrE, SdrC and SdrD proteins of different S. aureus lineages. Moreover, we demonstrated that the CnaBE3 domain was expressed in vivo during S. aureus infections, and that immunization of this domain alone significantly reduces the bacterial load in mice challenged with S. aureus. Furthermore, we show that the reduction of bacteria by CnaBE3 vaccination is due to functional antibodies. Finally, we demonstrated that the region of the SdrE protein containing the CnaBE3 domain was resistant to trypsin digestion, a characteristic often associated with the presence of an isopeptide bond.

  7. Protective activity of the CnaBE3 domain conserved among Staphylococcus aureus Sdr proteins.

    Directory of Open Access Journals (Sweden)

    Marco Becherelli

    Full Text Available Staphylococcus aureus is an opportunistic pathogen, commensal of the human skin and nares, but also responsible for invasive nosocomial as well as community acquired infections. Staphylococcus aureus adheres to the host tissues by means of surface adhesins, such as SdrC, SdrD, and SdrE proteins. The Sdr family of proteins together with a functional A domain, contain respectively two, three or five repeated sequences called B motifs which comprise the CnaB domains. SdrD and SdrE proteins were reported to be protective in animal models against invasive diseases or lethal challenge with human clinical S. aureus isolates. In this study we identified a 126 amino acid sequence containing a CnaB domain, conserved among the three Sdr proteins. The three fragments defined here as CnaBC2, D5 and E3 domains even though belonging to phylogenetically distinct strains, displayed high sequence similarity. Based on the sequence conservation data, we selected the CnaBE3 domain for further analysis and characterization. Polyclonal antibodies raised against the recombinant CnaBE3 domain recognized SdrE, SdrC and SdrD proteins of different S. aureus lineages. Moreover, we demonstrated that the CnaBE3 domain was expressed in vivo during S. aureus infections, and that immunization of this domain alone significantly reduces the bacterial load in mice challenged with S. aureus. Furthermore, we show that the reduction of bacteria by CnaBE3 vaccination is due to functional antibodies. Finally, we demonstrated that the region of the SdrE protein containing the CnaBE3 domain was resistant to trypsin digestion, a characteristic often associated with the presence of an isopeptide bond.

  8. Intracellular persisting Staphylococcus aureus is the major pathogen in recurrent tonsillitis.

    Directory of Open Access Journals (Sweden)

    Andreas E Zautner

    Full Text Available BACKGROUND: The two major indications for tonsillectomy are recurrent tonsillitis (RT and peritonsillar abscess (PTA. Unlike PTAs, which are primarily treated surgically, RT is often cured by tonsillectomy only after a series of failed drug therapy attempts. Although the bacteriological background of RT has been studied, the reason for the lack of success of conservative therapeutic approaches is not well understood. METHODS: In a prospective study, tonsil specimens from 130 RT patients and 124 PTA patients were examined for the presence of extra- and intracellular bacteria using antibiotic protection assays. Staphylococcus aureus isolates from RT patients were characterized by pulsed-field gel electrophoresis (PFGE, spa-typing and MSCRAMM-gene-PCR. Their ability for biofilm formation was tested and their cell invasiveness was confirmed by a flow cytometric invasion assay (FACS, fluorescent in situ hybridization (FISH and immunohistochemistry. FINDINGS: S. aureus was the predominant species (57.7% in RT patients, whereas Streptococcus pyogenes was most prevalent (20.2% in PTA patients. Three different assays (FACS, FISH, antibiotic protection assay showed that nearly all RT-associated S. aureus strains were located inside tonsillar cells. Correspondingly, the results of the MSCRAMM-gene-PCRs confirmed that 87% of these S. aureus isolates were invasive strains and not mere colonizers. Based upon PFGE analyses of genomic DNA and on spa-gene typing the vast majority of the S. aureus isolates belonged to different clonal lineages. CONCLUSIONS: Our results demonstrate that intracellular residing S. aureus is the most common cause of RT and indicate that S. aureus uses this location to survive the effects of antibiotics and the host immune response. A German translation of the Abstract is provided as supplementary material (Abstract S1.

  9. Colonization, Pathogenicity, Host Susceptibility and Therapeutics for Staphylococcus aureus: What is the Clinical Relevance?1

    Science.gov (United States)

    Tong, Steven Y.C.; Chen, Luke F.; Fowler, Vance G.

    2011-01-01

    Staphylococcus aureus is a human commensal that can also cause a broad spectrum of clinical disease. Factors associated with clinical disease are myriad and dynamic and include pathogen virulence, antimicrobial resistance and host susceptibility. Additionally, infection control measures aimed at the environmental niches of S. aureus and therapeutic advances continue to impact upon the incidence and outcomes of staphylococcal infections. This review article focuses on the clinical relevance of advances in our understanding of staphylococcal colonization, virulence, host susceptibility and therapeutics. Over the past decade key developments have arisen. First, rates of nosocomial methicillin-resistant S. aureus (MRSA) infections have significantly declined in many countries. Second, we have made great strides in our understanding of the molecular pathogenesis of S. aureus in general and community-associated MRSA in particular. Third, host risk factors for invasive staphylococcal infections, such as advancing age, increasing numbers of invasive medical interventions, and a growing proportion of patients with healthcare contact, remain dynamic. Finally, several new antimicrobial agents active against MRSA have become available for clinical use. Humans and S. aureus co-exist and the dynamic interface between host, pathogen and our attempts to influence these interactions will continue to rapidly change. Although progress has been made in the past decade, we are likely to face further surprises such as the recent waves of community-associated MRSA. PMID:22160374

  10. Neutrophil evasion strategies by Streptococcus pneumoniae and Staphylococcus aureus.

    Science.gov (United States)

    Lewis, Megan L; Surewaard, Bas G J

    2018-03-01

    Humans are well equipped to defend themselves against bacteria. The innate immune system employs diverse mechanisms to recognize, control and initiate a response that can destroy millions of different microbes. Microbes that evade the sophisticated innate immune system are able to escape detection and could become pathogens. The pathogens Streptococcus pneumoniae and Staphylococcus aureus are particularly successful due to the development of a wide variety of virulence strategies for bacterial pathogenesis and they invest significant efforts towards mechanisms that allow for neutrophil evasion. Neutrophils are a primary cellular defense and can rapidly kill invading microbes, which is an indispensable function for maintaining host health. This review compares the key features of Streptococcus pneumoniae and Staphylococcus aureus in epidemiology, with a specific focus on virulence mechanisms utilized to evade neutrophils in bacterial pathogenesis. It is important to understand the complex interactions between pathogenic bacteria and neutrophils so that we can disrupt the ability of pathogens to cause disease.

  11. Cataract surgery during active methicillin-resistant Staphylococcus aureus infection

    Directory of Open Access Journals (Sweden)

    Mansour AM

    2014-04-01

    Full Text Available Ahmad M Mansour,1,2 Haytham I Salti11Department of Ophthalmology, American University of Beirut, 2Rafic Hariri University Hospital, Beirut, LebanonAbstract: We present two patients with active, foul-smelling, methicillin-resistant ­Staphylococcus aureus (MRSA wounds of the forehead and sternum following craniotomy or open heart surgery. Both had debilitating cataracts and were told by the infectious diseases team that cataract surgery is very risky. Both underwent sequential bilateral phacoemulsification with no sign of infection. Patients with active MRSA wound infections may safely undergo cataract surgery with additional precautions observed intraoperatively (good wound construction and postoperatively (topical antibiotics and close observation. Banning such surgeries can unnecessarily jeopardize the lifestyles of such patients.Keywords: cataract, infection, methicillin-resistant Staphylococcus aureus, phacoe­mulsification

  12. Transmission of Staphylococcus aureus from mothers to newborns.

    Science.gov (United States)

    Leshem, Eyal; Maayan-Metzger, Ayala; Rahav, Galia; Dolitzki, Mordechai; Kuint, Jacob; Roytman, Yulia; Goral, Aviva; Novikov, Ilya; Fluss, Ronen; Keller, Nathan; Regev-Yochay, Gili

    2012-04-01

    The study objective was to define the risk factors and the route of Staphylococcus aureus transmission between mother and newborn. Women at late pregnancy were screened for nasal and vaginal S. aureus colonization. Newborns were screened for nasal, auricular, umbilical, and rectal colonization at birth and before discharge. Carrier mothers and their newborns were rescreened at 1 month. Pulse-field gel electrophoresis was used to assess strain genetic relatedness. Of the 208 women screened, 34% were colonized with S. aureus. Overall, by 72-100 hours after birth, the cumulative incidence of S. aureus acquisition was 42.6/100 newborns of carrier mothers versus 7.4/100 newborns of noncarrier mothers (adjusted risk ratio = 5.7; 95% confidence interval [CI], 2.3-13.9). The risk to acquire a maternal strain was significantly higher than nonmaternal strain (adjusted risk ratio = 1.5; 95% CI, 1.3-1.9); Newborns to carrier mothers were also at a risk to acquire nonmaternal S. aureus strains compared with newborns to noncarrier mothers (adjusted risk ratio = 2.9; 95% CI, 1.6-5.4). The cumulative incidence of S. aureus acquisition was similar among newborns delivered by cesarean versus vaginal delivery (24.5 vs. 23.0/100 cases). At 1-month follow-up, the cumulative incidence of S. aureus acquisition reached 69.7/100 newborns of carrier mothers.Genetically identical strains were isolated in 32/40 (80%) mother-newborn pairs, among these, the source of the newborn strain was a maternal nasal strain in 29/32 (90%). Newborns of carrier mothers are at risk to acquire S. aureus colonization. Most newborns of carrier mothers are colonized within the first month of life. Horizontal transmission from the mother is probably the major source for S. aureus carriage in newborns.

  13. Methicillin-resistant Staphylococcus aureus infection in the obstetric setting.

    Science.gov (United States)

    Kriebs, Jan M

    2008-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an increasingly prevalent pathogen, both in the community and in hospitalized patients. The virulence of MRSA, coupled with its resistance to many frequently prescribed antibiotics, requires increased vigilance in the assessment and diagnosis of skin and soft tissue infections. This article reviews the epidemiology of MRSA and focuses on treatment of MRSA when it is diagnosed during pregnancy.

  14. Staphylococcus aureus in locally produced white cheese in Tirana market

    OpenAIRE

    ELVIRA BELI; RENIS MAÇI; SONILA ÇOÇOLI; HALIT MEMOÇI

    2014-01-01

    Cheese has nutritional value, its consumption is very common in Albania, but is also excellent medium for bacterial growth, source of bacterial infection, particularly when it is produced from raw poor quality or unpasteurized milk. Microbial safety of cheeses may be enhanced by usage good quality raw milk, pasteurized milk, following GMP in aim to prevent cross-contamination. The aim of this study was to evaluate the presence and amount of Staphylococcus aureus in white cheeses, as an Albani...

  15. Methicillin-resistant Staphylococcus aureus survival on hospital fomites.

    Science.gov (United States)

    Huang, Robert; Mehta, Sanjay; Weed, Diane; Price, Connie Savor

    2006-11-01

    We examined the duration of survival of 2 strains of methicillin-resistant Staphylococcus aureus (MRSA) on 3 types of hospital fomites. MRSA survived for 11 days on a plastic patient chart, more than 12 days on a laminated tabletop, and 9 days on a cloth curtain. Irregular surfaces may help harbor organisms in the environment. In addition to contact precautions, MRSA containment during an outbreak should include concurrent environmental decontamination.

  16. Fatal pneumoni med Panton-Valentine-leukocidinproducerende Staphylococcus aureus

    DEFF Research Database (Denmark)

    Rabøl, Peter Hedelund; Dessau, Ram Benny; Warnecke, Mads

    2010-01-01

    We describe a case of fatal pneumonia in a previously healthy 14-year-old boy. The patient was severely affected at the time of admission with high fever, tachypnea, tachycardia and peripheral cyanosis. The condition worsened despite treatment with antibiotics as well as respiratory and pressure ...... support. Acidosis and critical leucopenia supervened and the patient died just short of 24 hours after admission. Subsequent bacterial cultivation showed Panton-Valentine Leucocidin-producing Staphylococcus aureus....

  17. Prevalence of Staphylococcus aureus colonization in renal transplant patients

    OpenAIRE

    Lamblet,Luiz Carlos Ribeiro; Barbosa,Dulce Aparecida

    2014-01-01

    Objective to evaluate the prevalence of Staphylococcus aureus nasal colonization in renal transplant patients and to identify the related risk factors. Method Swabs were used to collect nasal samples from 160 patients who had undergone a transplant within the previous year at the Kidney and Hypertension Hospital. The ‘National Committee for Clinical Laboratory Standards’ norms were followed for the collection, isolation, identification and sensitivity measurements. Results The...

  18. Diversity of Staphylococcus aureus Isolates in European Wildlife.

    Science.gov (United States)

    Monecke, Stefan; Gavier-Widén, Dolores; Hotzel, Helmut; Peters, Martin; Guenther, Sebastian; Lazaris, Alexandros; Loncaric, Igor; Müller, Elke; Reissig, Annett; Ruppelt-Lorz, Antje; Shore, Anna C; Walter, Birgit; Coleman, David C; Ehricht, Ralf

    2016-01-01

    Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST). The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963) were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock-associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation.

  19. Staphylococcus aureus phage types and their correlation to antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Mehndiratta P

    2010-10-01

    Full Text Available Context: Staphylococcus aureus is one of the most devastating human pathogen. The organism has a differential ability to spread and cause outbreak of infections. Characterization of these strains is important to control the spread of infection in the hospitals as well as in the community. Aim: To identify the currently existing phage groups of Staphylococcus aureus, their prevalence and resistance to antibiotics. Materials and Methods: Study was undertaken on 252 Staphylococcus aureus strains isolated from clinical samples. Strains were phage typed and their resistance to antibiotics was determined following standard microbiological procedures. Statistical Analysis: Chi square test was used to compare the antibiotic susceptibility between methicillin resistant Staph. aureus (MRSA and methicillin sensitive S. aureus (MSSA strains. Results: Prevalence of MRSA and MSSA strains was found to be 29.36% and 70.65% respectively. Of these 17.56% of MRSA and 40.44% of MSSA strains were community acquired. All the MSSA strains belonging to phage type 81 from the community were sensitive to all the antibiotics tested including clindamycin and were resistant to penicillin. Forty five percent strains of phage group III and 39% of non-typable MRSA strains from the hospital were resistant to multiple antibiotics. Conclusion: The study revealed that predominant phage group amongst MRSA strains was phage group III and amongst MSSA from the community was phage group NA (phage type 81. MSSA strains isolated from the community differed significantly from hospital strains in their phage type and antibiotic susceptibility. A good correlation was observed between community acquired strains of phage type 81 and sensitivity to gentamycin and clindamycin.

  20. Diversity of Staphylococcus aureus Isolates in European Wildlife

    Science.gov (United States)

    Monecke, Stefan; Gavier-Widén, Dolores; Hotzel, Helmut; Peters, Martin; Guenther, Sebastian; Lazaris, Alexandros; Loncaric, Igor; Müller, Elke; Reissig, Annett; Ruppelt-Lorz, Antje; Shore, Anna C.; Walter, Birgit; Coleman, David C.; Ehricht, Ralf

    2016-01-01

    Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST). The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963) were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock-associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation. PMID:27992523

  1. Prevalence of Staphylococcus aureus colonization in renal transplant patients

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Ribeiro Lamblet

    2014-10-01

    Full Text Available Objective to evaluate the prevalence of Staphylococcus aureus nasal colonization in renal transplant patients and to identify the related risk factors. Method Swabs were used to collect nasal samples from 160 patients who had undergone a transplant within the previous year at the Kidney and Hypertension Hospital. The ‘National Committee for Clinical Laboratory Standards’ norms were followed for the collection, isolation, identification and sensitivity measurements. Results There was a 9.4% (15 prevalence of Staphylococcus aureus nasal colonization, of which one (6.7% was resistant to oxacillin. It was possible to identify as an associated risk factor a wait of more than one year for accessing dialysis prior to the transplant (p=0.029. Conclusion Given the high morbidity and mortality rates that this microorganism causes in the target population, other studies should be carried out, and pre- and post-transplant screening should occur in order to develop strategies that improve the prevention and control of the spread of Staphylococcus aureus.

  2. Nickel allergy and relationship with Staphylococcus aureus in atopic dermatitis.

    Science.gov (United States)

    Bogdali, Anna M; Anna, Bogdali M; Grazyna, Antoszczyk; Wojciech, Dyga; Aleksander, Obtulowicz; Anna, Bialecka; Andrzej, Kasprowicz; Zofia, Magnowska; Krystyna, Obtulowicz

    2016-01-01

    The increase of nickel air pollution is supposed to frequent side effects of nickel action related to virulence potential of Staphylococcus aureus in patients with nickel allergy in atopic dermatitis. The goal was to investigate the relationship between nickel allergy and infection by S. aureus in atopic dermatitis. Nickel allergy was confirmed in atopic patients and excluded in healthy volunteers using patch testing. Infection by S. aureus was tested in atopic patients and healthy volunteers by use of API Staph system. The specific IgE for staphylococcal enterotoxin A and B were measured. Secretion of IFN-g, IL-2, IL-13 by PBMC under nickel sulfate and the enterotoxins A and B stimulations were studied with ELISpot. We found the increased number of infections by S. aureus in atopic patients with nickel allergy in comparison to atopic patients and healthy volunteers without nickel allergy. The elevated secretion of IL-2 under nickel sulfate stimulation in vitro was exclusively found in atopic patients with nickel allergy infected by S. aureus. Our data suggest that nickel allergy and infection by S. aureus are linked in atopic dermatitis. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Pheno- and Genotyping of Staphylococcus aureus Isolates of Sheep Origin

    Directory of Open Access Journals (Sweden)

    Jana Mašlanková

    2009-01-01

    Full Text Available The aim of the study was to determine the prevalence of genes encoding virulence factors in Staphylococcus aureus strains isolated from raw sheep milk, sheep cheese and Bryndza cheese. Genes encoding staphylococcal enterotoxin (sea, seb, sec, sed and see, toxic shock syndrome toxin-1 (tst, exfoliative toxins (eta and etb and collagen-binding protein (cna were detected. In a total of 79 S. aureus isolates all assessed toxins encoding genes were found, except for see, eta and etb. Overall, 75.9% of S. aureus isolates were found to be positive for one or more toxin genes. The sec gene was found most frequently (24.1%, followed by tst (22.8%, seb (13.9%, sed (10.1% and sea (5.1%. The cna gene was detected in 55.7% of S. aureus isolates. Based on tandem repeats in coa gene, five coa types were observed, further divided into 16 subtypes based on their RFLP pattern. Similarly tandem repeats in spa gene divided S. aureus isolates into 7 types. In the parallel antibiotic resistance study, 69.6% isolates were resistant to at least one of the 11 tested antibiotics. The pheno- and genotyping of S. aureus isolates of sheep origin presented in this work update the epidemiological data in Slovakia.

  4. Resistance to Antimicrobials Mediated by Efflux Pumps in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Isabel Couto

    2013-03-01

    Full Text Available Resistance mediated by efflux has been recognized in Staphylococcus aureus in the last few decades, although its clinical relevance has only been recognized recently. The existence of only a few studies on the individual and overall contribution of efflux to resistance phenotypes associated with the need of well-established methods to assess efflux activity in clinical isolates contributes greatly to the lack of solid knowledge of this mechanism in S. aureus. This study aims to provide information on approaches useful to the assessment and characterization of efflux activity, as well as contributing to our understanding of the role of efflux to phenotypes of antibiotic resistance and biocide tolerance in S. aureus clinical isolates. The results described show that efflux is an important contributor to fluoroquinolone resistance in S. aureus and suggest it as a major mechanism in the early stages of resistance development. We also show that efflux plays an important role on the reduced susceptibility to biocides in S. aureus, strengthening the importance of this long neglected resistance mechanism to the persistence and proliferation of antibiotic/biocide-resistant S. aureus in the hospital environment.

  5. What’s in a Name? Is Methicillin-Resistant Staphylococcus aureus Just Another S aureus When Treated with Vancomycin

    Science.gov (United States)

    1989-12-01

    of test to detect methicilin - resistant strains of Staphylococcus aureua. J Clin their longer hospitalizations and more severe injuries, had Microbiot...10u f DMRMM STAUXN PLIPoove to lo pu~bi~c releaseB - - 1 C6 01 In SWhat’s in a Name? Is Methicillin- Resistant <Staphylococcus aureus Just Another S... resistant Staphylococcus aureus (MRSA) strains, hospital and the community, infections caused by these new principally resistant to penicilllnase

  6. Immuno-targeting of Staphylococcus aureus via surface remodeling complexes.

    Science.gov (United States)

    Sabulski, Mary J; Pidgeon, Sean E; Pires, Marcos M

    2017-10-01

    Agents with novel mechanisms of action are needed to complement traditional antibiotics. Towards these goals, we have exploited the surface-homing properties of vancomycin to tag the surface of Gram-positive pathogens with immune cell attractants in two unique modes. First, vancomycin was conjugated to the small molecule hapten 2,4-dinitrophenol (DNP) to promote bacterial opsonization. Second, we built on these results by improving the tagging specificity and mechanism of incorporation by coupling it to a sortase A substrate peptide. We demonstrated, for the first time, that the surface of Staphylococcus aureus ( S. aureus ) can be metabolically labeled in live Caenorhabditis elegans hosts. These constructs represent a class of promising narrow-spectrum agents that target S. aureus for opsonization and establish a new surface labeling modality in live host organisms, which should be a powerful tool in dissecting features of host-pathogen interactions.

  7. Bats are rare reservoirs of Staphylococcus aureus complex in Gabon.

    Science.gov (United States)

    Held, Jana; Gmeiner, Markus; Mordmüller, Benjamin; Matsiégui, Pierre-Blaise; Schaer, Juliane; Eckerle, Isabella; Weber, Natalie; Matuschewski, Kai; Bletz, Stefan; Schaumburg, Frieder

    2017-01-01

    The colonization of afro-tropical wildlife with Staphylococcus aureus and the derived clade Staphylococcus schweitzeri remains largely unknown. A reservoir in bats could be of importance since bats and humans share overlapping habitats. In addition, bats are food sources in some African regions and can be the cause of zoonotic diseases. Here, we present a cross-sectional survey employing pharyngeal swabs of captured and released bats (n=133) in a forest area of Gabon. We detected low colonization rates of S. aureus (4-6%) and S. schweitzeri (4%) in two out of four species of fruit bats, namely Rousettus aegyptiacus and Micropteropus pusillus, but not in insectivorous bats. Multilocus sequence typing showed that S. aureus from Gabonese bats (ST2984, ST3259, ST3301, ST3302) were distinct from major African human associated clones (ST15, ST121, ST152). S. schweitzeri from bats (ST1697, ST1700) clustered with S. schweitzeri from other species (bats, monkeys) from Nigeria and Côte d'Ivoire. In conclusion, colonization rates of bats with S. aureus and S. schweitzeri were low in our study. Phylogenetic analysis supports an intense geographical dispersal of S. schweitzeri among different mammalian wildlife hosts. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Methicillin-resistant Staphylococcus aureus has greater risk of transmission in the operating room than methicillin-sensitive S aureus.

    Science.gov (United States)

    Loftus, Randy W; Dexter, Franklin; Robinson, Alysha D M

    2018-01-04

    Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogenic S aureus strain characteristic associated with increased patient morbidity and mortality. The health care system needs to understand MRSA transmissibility in all settings to improve basic preventive measures to generate sustained reductions in invasive MRSA infections. Our primary aim was to compare intraoperative transmissibility of MRSA versus methicillin-sensitive S aureus (MSSA) isolates. S aureus isolates (N = 173) collected from 274 randomly selected operating room environments (first and second case of the day in each operating room, a case pair) at 3 hospitals underwent systematic-phenotypic and genomic processing to identify clonally related transmission events. Confirmed transmission events were defined as at least 2 S aureus isolates obtained from ≥2 distinct intraoperative reservoirs sampled within or between cases in a study unit that were epidemiologically and clonally related. We explored the relationship between clonal transmission and methicillin resistance with Poisson regression analysis. We identified 58 clonal transmission events. MRSA isolates were associated with increased risk of clonal transmission compared with MSSA isolates (adjusted incidence risk ratio [IRR], 1.68; 95% confidence interval [CI], 1.13-2.49; P = .010; unadjusted IRR, 1.85; 95% CI, 1.23-2.77; P = .003, respectively). MRSA isolates are associated with increased risk of intraoperative transmission. Future work should examine the impact of the attenuation of intraoperative MRSA transmission on the incidence of invasive MRSA infections. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  9. Effect of Substance P in Staphylococcus aureus and Staphylococcus epidermidis virulence: Implication for skin homeostasis

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    Awa eNdiaye

    2016-04-01

    Full Text Available Staphylococcus aureus and Staphylococcus epidermidis are two major skin associated bacteria, and Substance P (SP is a major skin neuropeptide. Since bacteria are known to sense and response to many human hormones, we investigated the effects of SP on Staphylococci virulence in reconstructed human epidermis model and HaCaT keratinocytes. We show that SP is stimulating the virulence of Staphylococcus aureus and Staphylococcus epidermidis in a reconstructed human epidermis model. qRT-PCR array analysis of 64 genes expressed by keratinocytes in the response to bacterial infection revealed a potential link between the action of SP on Staphylococci and skin physiopathology. qRT-PCR and direct assay of cathelicidin and human β-defensin 2 secretion also provided that demonstration that the action of SP on bacteria is independent of antimicrobial peptide expression by keratinocytes. Considering an effect of SP on S. aureus and S. epidermidis, we observed that SP increases the adhesion potential of both bacteria on keratinocytes. However, SP modulates the virulence of S. aureus and S. epidermidis through different mechanisms. The response of S. aureus is associated with an increase in Staphylococcal Enterotoxin C2 (SEC2 production and a reduction of exolipase processing whereas in S. epidermidis the effect of SP appears mediated by a rise in biofilm formation activity. The Thermo unstable ribosomal Elongation factor Ef-Tu was identified as the SP-interacting protein in S. aureus and S. epidermidis. SP appears as an inter-kingdom communication factor involved in the regulation of bacterial virulence and essential for skin microflora homeostasis.

  10. PREVALENCIA DE Staphylococcus epidermidis Y Staphylococcus aureus EN PACIENTES CON CONJUNTIVITIS

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    P. Hernández-Rodríguez

    2005-12-01

    Full Text Available Con el fin de establecer la prevalencia de Staphylococcus epidermidis y Staphylococcus aureus en pacientes con conjuntivitis, se evaluaron clínica y bacteriológicamente 131 pacientes con diagnóstico clínico presuntivo de conjuntivitis. A cada participante se le tomó muestra de secreción ocular, para la coloración de Gram y cultivo; además, se probó la susceptibilidad de los aislamientos frente a Oxacilina (Ox, Gentamicina (GM, Vancomicina (Va, Trimetoprim Sulfamethoxazole (SXT, Tetraciclina (Te, Cefalothin (CF, Ceftriaxone (CRO y Ciprofloxacina (CIP. El 53% de los cultivos bacteriológicos fueron positivos, donde el 87% de los aislamientos correspondieron a Gram positivos, siendo los más frecuentes Staphylococcus epidermidis (43%, Staphylococcus aureus (30%, Streptococcus sp. (15%, Enterococcus (7%, Corynebacterium sp. 5%. Se observó multirresistencia frente a 3 ó más antibióticos en S. epidermidis (44% y S.aureus (42%. La alta frecuencia de estos microorganismos y la multirresistencia encontrada en este estudio, determinan la importancia que tienen, como posibles patógenos oculares, y la necesidad de implementar las pruebas de susceptibilidad bacteriana en el ámbito oftalmológico. Este es el primer estudio publicado en Colombia sobre la prevalencia de Staphylococcus epidermidis y Staphylococcus aureus en pacientes con conjuntivitis, el cual seguramente originará la iniciación de posteriores investigaciones, encaminadas a determinar el verdadero papel de estos microorganismos, en el proceso infeccioso ocular.

  11. Staphylococcus aureus in the community: colonization versus infection.

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    Maureen Miller

    Full Text Available BACKGROUND: Antibiotic-resistant Staphylococcus aureus infections have increased dramatically in the community, yet S. aureus nasal colonization has remained stable. The objectives of this study were to determine if S. aureus colonization is a useful proxy measure to study disease transmission and infection in community settings, and to identify potential community reservoirs. METHODOLOGY/PRINCIPAL FINDINGS: Randomly selected households in Northern Manhattan, completed a structured social network questionnaire and provided nasal swabs that were typed by pulsed field gel electrophoresis to identify S. aureus colonizing strains. The main outcome measures were: 1 colonization with S. aureus; and 2 recent serious skin infection. Risk factor analyses were conducted at both the individual and the household levels; logistic regression models identified independent risks for household colonization and infection. RESULTS: 321 surveyed households contained 914 members. The S. aureus prevalence was 25% and MRSA was 0.4%. More than 40% of households were colonized. Recent antibiotic use was the only significant correlate for household colonization (p = .002. Seventy-eight (24% households reported serious skin infection. In contrast with colonization, five of the six risk factors that increased the risk of skin infection in the household at the univariate level remained independently significant in multivariable analysis: international travel, sports participation, surgery, antibiotic use and towel sharing. S. aureus colonization was not significantly associated with serious skin infection in any analysis. Among multiperson households with more than one person colonized, 50% carried the same strain. CONCLUSIONS/SIGNIFICANCE: The lack of association between S. aureus nasal colonization and serious skin infection underscores the need to explore alternative venues or body sites that may be crucial to transmission. Moreover, the magnitude of colonization and

  12. Bovine Staphylococcus aureus: Subtyping, evolution, and zoonotic transfer.

    Science.gov (United States)

    Boss, R; Cosandey, A; Luini, M; Artursson, K; Bardiau, M; Breitenwieser, F; Hehenberger, E; Lam, Th; Mansfeld, M; Michel, A; Mösslacher, G; Naskova, J; Nelson, S; Podpečan, O; Raemy, A; Ryan, E; Salat, O; Zangerl, P; Steiner, A; Graber, H U

    2016-01-01

    Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies using ribosomal spacer (RS)-PCR, however, demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infections are genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. Furthermore, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. In addition to RS-PCR, other methods for subtyping Staph. aureus are known, including spa typing and multilocus sequence typing (MLST). They are based on sequencing the spa and various housekeeping genes, respectively. The aim of the present study was to compare the 3 analytic methods using 456 strains of Staph. aureus isolated from milk of bovine intramammary infections and bulk tanks obtained from 12 European countries. Furthermore, the phylogeny of animal Staph. aureus was inferred and the zoonotic transfer of Staph. aureus between cattle and humans was studied. The analyzed strains could be grouped into 6 genotypic clusters, with CLB, CLC, and CLR being the most prominent ones. Comparing the 3 subtyping methods, RS-PCR showed the highest resolution, followed by spa typing and MLST. We found associations among the methods but in many cases they were unsatisfactory except for CLB and CLC. Cluster CLB was positive for clonal complex (CC)8 in 99% of the cases and typically positive for t2953; it is the cattle-adapted form of CC8. Cluster CLC was always positive for tbl 2645 and typically positive for CC705. For CLR and the remaining subtypes, links among the 3 methods were generally poor. Bovine Staph. aureus is highly clonal and a few clones predominate. Animal Staph. aureus always evolve from human strains, such that every human strain may be the ancestor of a novel animal-adapted strain. The zoonotic transfer of IMI- and milk-associated strains

  13. Mupirocin prophylaxis against nosocomial Staphylococcus aureus infections in nonsurgical patients: a randomized study

    NARCIS (Netherlands)

    M.C. Vos (Margreet); A. Ott (Alewijn); A. Voss (Andreas); J.A.J.W. Kluytmans (Jan); C.M.J.E. Vandenbroucke-Grauls (Christina); M.H.M. Meester (Marlene); P.H.J. van Keulen (Peter); H.A. Verbrugh (Henri); H.F.L. Wertheim (Heiman)

    2004-01-01

    textabstractBACKGROUND: Staphylococcus aureus nasal carriage is a major risk factor for nosocomial S. aureus infection. Studies show that intranasal mupirocin can prevent nosocomial surgical site infections. No data are available on the efficacy of mupirocin in nonsurgical

  14. External quality assessment of the molecular diagnostics and genotyping of meticillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    R. te Witt (René); A.F. van Belkum (Alex); W.G. MacKay (William); P.S. Wallace; W.B. van Leeuwen (Willem)

    2010-01-01

    textabstractTwo multicentre external quality assessments (EQA) for the molecular detection and genotyping of meticillin-resistant Staphylococcus aureus (MRSA) were arranged. Firstly, 11 samples containing various amounts of inactivated MRSA strains, meticillin-susceptible S. aureus (MSSA),

  15. ANTISTAPHYBASE: database of antimicrobial peptides (AMPs) and essential oils (EOs) against methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus.

    Science.gov (United States)

    Zouhir, Abdelmajid; Taieb, Malek; Lamine, Mohamed Ashraf; Cherif, Ammar; Jridi, Taoufik; Mahjoubi, Basma; Mbarek, Sarra; Fliss, Ismail; Nefzi, Adel; Sebei, Khaled; Ben Hamida, Jeannette

    2017-03-01

    Staphylococcus aureus and methicillin-resistant S. aureus are major pathogens. The antimicrobial peptides and essential oils (EOs) display narrow- or broad-spectrum activity against bacteria including these strains. A centralized resource, such as a database, designed specifically for anti-S. aureus/anti-methicillin-resistant S. aureus antimicrobial peptides and EOs is therefore needed to facilitate the comprehensive investigation of their structure/activity associations and combinations. The database ANTISTAPHYBASE is created to facilitate access to important information on antimicrobial peptides and essential peptides against methicillin-resistant S. aureus and S. aureus. At the moment, the database contains 596 sequences of antimicrobial peptides produced by diverse organisms and 287 essential oil records. It permits a quick and easy search of peptides based on their activity as well as their general, physicochemical properties and literature data. These data are very useful to perform further bioinformatic or chemometric analysis and would certainly be useful for the development of new drugs for medical use. The ANTISTAPHYBASE database is freely available at: https://www.antistaphybase.com/ .

  16. Gastrointestinal dissemination and transmission of Staphylococcus aureus following bacteremia.

    Science.gov (United States)

    Kernbauer, Elisabeth; Maurer, Katie; Torres, Victor J; Shopsin, Bo; Cadwell, Ken

    2015-01-01

    Mutations that alter virulence and antibiotic susceptibility arise and persist during Staphylococcus aureus bacteremia. However, an experimental system demonstrating transmission following bacteremia has been lacking, and thus implications of within-host adaptation for between-host transmission are unknown. We report that S. aureus disseminates to the gastrointestinal tract of mice following intravenous injection and readily transmits to cohoused naive mice. Both intestinal dissemination and transmission were linked to the production of virulence factors based on gene deletion studies of the sae and agr two-component systems. Furthermore, antimicrobial selection for antibiotic-resistant S. aureus displaced susceptible S. aureus from the intestine of infected hosts, which led to the preferential transmission and dominance of antibiotic-resistant bacteria among cohoused untreated mice. These findings establish an animal model to investigate gastrointestinal dissemination and transmission of S. aureus and suggest that adaptation during the course of systemic infection has implications beyond the level of a single host. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  17. Prevalence of Staphylococcus aureus in Shrimps in Tehran during 2013

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    Mohammad Mehdi Soltan Dallal

    2016-02-01

    Full Text Available Background During fishing and transport, preservation and quality of fish products are importantas well as storage to prevent the growth of pathogenic and toxin producing bacteria.Staphylococcus aureus is one of the most common causes of sea food-borne diseases worldwidedue to contamination of food by preformed enterotoxins. The aim of this study was to compare theprevalence and contamination of S. aureus in marine and farmed shrimps in Tehran fishery center.Methods: A total of 300 samples, including 150 marine, 150 farmed shrimps were selected duringSeptember 2013 to December 2014. Isolation and identification of S. aureus from isolated sampleswere carried out according to conventional methods, and antibiotic susceptibility test wasperformed by modified Kirby-Bauer disc diffusion method.Results: The results of this study showed that 30% of marine and 20% off armed shrimps werecontaminated with S. aureus. The highest resistance was observed with penicillin and ampicillin,whereas 100% were sensitive to vancomycin, clindamycin, ciprofloxacin, and rifampin.Conclusions: Due to relatively high contamination of shrimp by S. aureus more attention shouldbe given during processing and manufacturing.

  18. Prevalence of Staphylococcus aureus in Shrimps in Tehran during 2013

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Soltan Dallal

    2015-12-01

    Full Text Available Background During fishing and transport, preservation and quality of fish products are importantas well as storage to prevent the growth of pathogenic and toxin producing bacteria.Staphylococcus aureus is one of the most common causes of sea food-borne diseases worldwidedue to contamination of food by preformed enterotoxins. The aim of this study was to compare theprevalence and contamination of S. aureus in marine and farmed shrimps in Tehran fishery center.Methods: A total of 300 samples, including 150 marine, 150 farmed shrimps were selected duringSeptember 2013 to December 2013. Isolation and identification of S. aureus from isolated sampleswere carried out according to conventional methods, and antibiotic susceptibility test wasperformed by modified Kirby-Bauer disc diffusion methodResults: The results of this study showed that 30% of marine and 20% off armed shrimps werecontaminated with S. aureus. The highest resistance was observed with penicillin and ampicillin,whereas 100% were sensitive to vancomycin, clindamycin, ciprofloxacin, and rifampin.Conclusions: Due to relatively high contamination of shrimp by S. aureus more attention shouldbe given during processing and manufacturing.

  19. Role of nasal carriage of Staphylococcus aureus in chronic urticaria

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    Ashimav Deb Sharma

    2012-01-01

    Full Text Available Aim: To evaluate the role of nasal carriage of Staphylococcus aureus in patients suffering from chronic urticaria. Method: All total 82 patients were included for this study. Study group comprised 57 patients with chronic urticaria and the control group comprised 25 healthy volunteers. Nasal swab specimens were taken from all the 82 patients for bacterial culture and antimicrobial sensitivity. Patients with chronic urticaria who had positive growth for S. aureus were treated with sensitive antimicrobial agent. Nasal swab specimens were taken again from all the patients who received antimicrobial therapy to ensure complete eradication of S. aureus. All patients were followed up for a period of 6 weeks after the treatment. Urticarial activity was measured with the help of urticarial activity score. Results: S. aureus was detected in swab specimens from the nasal cavity in 32 patients in the study group and 7 patients in the control group. In the study group, after the antimicrobial treatment, 9 patients (28.12% had complete recovery from urticaria during the follow-up period; 4 patients (12.5% showed partial recovery from urticaria while the remaining patients (59.37% continued to suffer from urticaria. Conclusion: This study showed that nasal carriage of S. aureus can act as an etiological factor in chronic urticaria.

  20. The Bicomponent Pore-Forming Leucocidins of Staphylococcus aureus

    Science.gov (United States)

    Alonzo, Francis

    2014-01-01

    SUMMARY The ability to produce water-soluble proteins with the capacity to oligomerize and form pores within cellular lipid bilayers is a trait conserved among nearly all forms of life, including humans, single-celled eukaryotes, and numerous bacterial species. In bacteria, some of the most notable pore-forming molecules are protein toxins that interact with mammalian cell membranes to promote lysis, deliver effectors, and modulate cellular homeostasis. Of the bacterial species capable of producing pore-forming toxic molecules, the Gram-positive pathogen Staphylococcus aureus is one of the most notorious. S. aureus can produce seven different pore-forming protein toxins, all of which are believed to play a unique role in promoting the ability of the organism to cause disease in humans and other mammals. The most diverse of these pore-forming toxins, in terms of both functional activity and global representation within S. aureus clinical isolates, are the bicomponent leucocidins. From the first description of their activity on host immune cells over 100 years ago to the detailed investigations of their biochemical function today, the leucocidins remain at the forefront of S. aureus pathogenesis research initiatives. Study of their mode of action is of immediate interest in the realm of therapeutic agent design as well as for studies of bacterial pathogenesis. This review provides an updated perspective on our understanding of the S. aureus leucocidins and their function, specificity, and potential as therapeutic targets. PMID:24847020

  1. Virulence potential of Staphylococcus aureus isolates from Buruli ulcer patients.

    Science.gov (United States)

    Amissah, Nana Ama; Chlebowicz, Monika A; Ablordey, Anthony; Tetteh, Caitlin S; Prah, Isaac; van der Werf, Tjip S; Friedrich, Alex W; van Dijl, Jan Maarten; Stienstra, Ymkje; Rossen, John W

    2017-06-01

    Buruli ulcer (BU) is a necrotizing infection of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. BU wounds may also be colonized with other microorganisms including Staphylococcus aureus. This study aimed to characterize the virulence factors of S. aureus isolated from BU patients. Previously sequenced genomes of 21 S. aureus isolates from BU patients were screened for the presence of virulence genes. The results show that all S. aureus isolates harbored on their core genomes genes for known virulence factors like α-hemolysin, and the α- and β-phenol soluble modulins. Besides the core genome virulence genes, mobile genetic elements (MGEs), i.e. prophages, genomic islands, pathogenicity islands and a Staphylococcal cassette chromosome (SCC) were found to carry different combinations of virulence factors, among them genes that are known to encode factors that promote immune evasion, superantigens and Panton-Valentine Leucocidin. The present observations imply that the S. aureus isolates from BU patients harbor a diverse repertoire of virulence genes that may enhance bacterial survival and persistence in the wound environment and potentially contribute to delayed wound healing. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

  2. Ocorrência de Staphylococcus aureus em queijo tipo "frescal" Occurrence of Staphylococcus aureus in cheese made in Brazil

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    Edvaldo Sampaio de Almeida Filho

    2000-12-01

    Full Text Available OBJETIVO: Verificar a ocorrência de Staphylococcus aureus em uma amostra de queijo tipo Minas "frescal" comercializado na cidade de Poços de Caldas, MG, de modo a obter subsídios que permitam avaliar o risco potencial que este produto pode representar para a saúde da população consumidora. MÉTODOS: Foi investigada a presença e o número de cepas de Staphylococcus aureus em 80 amostras de queijo tipo Minas "frescal" produzido artesanalmente e comercializado na cidade de Poços de Caldas, MG, Brasil. RESULTADOS: Os resultados obtidos evidenciaram a presença de S. aureus em 40 (50,0% amostras, cujas contagens revelaram valores médios em torno de 10(5/g. CONCLUSÕES: Tais achados parecem ser extremamente preocupantes, pois além de se situarem acima do limite máximo de 10³/g estabelecido pelo Ministério da Saúde, estes valores mostraram-se muito próximos dos requeridos para a produção de enterotoxinas em quantidades suficientes para a ocorrência de surtos de intoxicação alimentar estafilocócica.OBJECTIVE: To verify the occurrence of Staphylococcus aureus in a sample of cheese sold in a city of the Southeastern region of Brazil and assess the potential risk for the consumers. METHODS: Eighty samples of homemade cheese sold in a city of the southern region of Brazil were evaluated for the presence and the most probable number of Staphylococcus aureus agents. RESULTS: The study revealed the presence of S. aureus in 40 samples (50.0%, with a mean count of 10(5/g. CONCLUSION: These results are worrisome because the Health Ministry has established a safety threshold of 10³/g, and the values obtained are close to the number of bacteria able to produce enough enterotoxins to cause a foodborne disease outbreak.

  3. Staphylococcus aureus small colony variants in diabetic foot infections

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    Estrella Cervantes-García

    2015-03-01

    Full Text Available Background: Staphylococcus aureus (S. aureus is one of the major pathogens causing chronic infections. The ability of S. aureus to acquire resistance to a diverse range of antimicrobial compounds results in limited treatment options, particularly in methicillin-resistant S. aureus (MRSA. A mechanism by which S. aureus develops reduced susceptibility to antimicrobials is through the formation of small colony variants (SCVs. Infections by SCVs of S. aureus are an upcoming problem due to difficulties in laboratory diagnosis and resistance to antimicrobial therapy. Methods: A prospective study was performed on 120 patients diagnosed with both type 2 diabetes mellitus and infected diabetic foot ulcers. The study was carried out from July 2012 to December 2013 in Hospital General de Mexico. The samples were cultured in blood agar, mannitol salt agar, and MacConkey agar media, and incubated at 37°C in aerobic conditions. Results: We describe the first known cases of diabetic foot infections caused by MRSA-SCVs in patients diagnosed with type 2 diabetes mellitus and infected diabetic foot ulcers. In all of our cases, the patients had not received any form of gentamicin therapy. Conclusions: The antibiotic therapy commonly used in diabetic patients with infected diabetic foot ulcers fails in the case of MRSA-SCVs because the intracellular location protects S. aureus-SCVs from the host's defenses and also helps them resist antibiotics. The cases studied in this article add to the spectrum of persistent and relapsing infections attributed to MRSA-SCVs and emphasizes that these variants may also play a relevant role in diabetic foot infections.

  4. Staphylococcus aureus from the German general population is highly diverse.

    Science.gov (United States)

    Becker, Karsten; Schaumburg, Frieder; Fegeler, Christian; Friedrich, Alexander W; Köck, Robin

    2017-01-01

    This prospective cohort study evaluates colonization dynamics and molecular characteristics of methicillin-susceptible and - resistant Staphylococcus aureus (MSSA/MRSA) in a German general population. Nasal swabs of 1878 non-hospitalized adults were screened for S. aureus. Participants were screened thrice in intervals of 6-8 months. Isolates were characterized by spa and agr typing, mecA and mecC possession, respectively, and PCRs targeting virulence factors. 40.9% of all participants carried S. aureus at least once while 0.7% of the participants carried MRSA (mainly spa t011). MSSA isolates (n=1359) were associated with 331 different spa types; t084 (7.7%), t091 (6.1%) and t012 (71, 5.2%) were predominant. Of 206 participants carrying S. aureus at all three sampling time points, 14.1% carried the same spa type continuously; 5.3% carried different spa types with similar repeat patterns, but 80.6% carried S. aureus with unrelated spa types. MSSA isolates frequently harboured genes encoding enterotoxins (sec: 16.6%, seg: 63.1%, sei: 64.5%) and toxic shock syndrome toxin (tst: 17.5%), but rarely Panton-Valentine leukocidin (lukS-PV/lukF-PV: 0.2%). MSSA colonizing human nares in the community are clonally highly diverse. Among those constantly carrying S. aureus, clonal lineages changed over time. The proportion of persistent S. aureus carriers was lower than reported elsewhere. Copyright © 2016 Elsevier GmbH. All rights reserved.

  5. Lugol's solution eradicates Staphylococcus aureus biofilm in vitro.

    Science.gov (United States)

    Grønseth, Torstein; Vestby, Lene K; Nesse, Live L; Thoen, Even; Habimana, Olivier; von Unge, Magnus; Silvola, Juha T

    2017-12-01

    The aim of the study was to evaluate the antibacterial efficacy of Lugol's solution, acetic acid, and boric acid against Staphylococcus aureus biofilm. The efficacy of Lugol's solution 1%, 0.1%, and 0.05%, acetic acid 5% or boric acid 4.7% for treatment of Staphylococcus aureus biofilm in vitro was tested using 30 clinical strains. Susceptibility in the planktonic state was assessed by disk diffusion test. Antiseptic effect on bacteria in biofilm was evaluated by using a Biofilm-oriented antiseptic test (BOAT) based on metabolic activity, a biofilm bactericidal test based on culturing of surviving bacteria and confocal laser scanning microscopy combined with LIVE/DEAD staining. In the planktonic state, all tested S. aureus strains were susceptible to Lugol's solution and acetic acid, while 27 out of 30 tested strains were susceptible to boric acid. In biofilm the metabolic activity was significantly reduced following exposure to Lugol's solution and 5% acetic acid, while boric acid exposure led to no significant changes in metabolic activities. In biofilm, biocidal activity was observed for Lugol's solution 1% (30/30), 0.1% (30/30), and 0.05% (26/30). Acetic acid and boric acid showed no bactericidal activity in this test. Confocal laser scanning microscopy, assessed in 4/30 strains, revealed significantly fewer viable biofilm bacteria with Lugol's solution (1% p Lugol's solution 1.0% and 0.1% effectively eradicated S. aureus in biofilm and could be an alternative to conventional topical antibiotics where S. aureus biofilm is suspected such as external otitis, pharyngitis and wounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Staphylococcus aureus hijacks a skin commensal to intensify its virulence: immunization targeting β-hemolysin and CAMP factor.

    Science.gov (United States)

    Lo, Chih-Wei; Lai, Yiu-Kay; Liu, Yu-Tsueng; Gallo, Richard L; Huang, Chun-Ming

    2011-02-01

    The need for a new anti-Staphylococcus aureus therapy that can effectively cripple bacterial infection, neutralize secretory virulence factors, and lower the risk of creating bacterial resistance is undisputed. Here, we propose what is, to our knowledge, a previously unreported infectious mechanism by which S. aureus may commandeer Propionibacterium acnes, a key member of the human skin microbiome, to spread its invasion and highlight two secretory virulence factors (S. aureus β-hemolysin and P. acnes CAMP (Christie, Atkins, Munch-Peterson) factor) as potential molecular targets for immunotherapy against S. aureus infection. Our data demonstrate that the hemolysis and cytolysis by S. aureus were noticeably augmented when S. aureus was grown with P. acnes. The augmentation was significantly abrogated when the P. acnes CAMP factor was neutralized or β-hemolysin of S. aureus was mutated. In addition, the hemolysis and cytolysis of recombinant β-hemolysin were markedly enhanced by recombinant CAMP factor. Furthermore, P. acnes exacerbated S. aureus-induced skin lesions in vivo. The combination of CAMP factor neutralization and β-hemolysin immunization cooperatively suppressed the skin lesions caused by coinfection of P. acnes and S. aureus. These observations suggest a previously unreported immunotherapy targeting the interaction of S. aureus with a skin commensal.

  7. Ocorrência de Staphylococcus aureus em queijo tipo "frescal"

    Directory of Open Access Journals (Sweden)

    Almeida Filho Edvaldo Sampaio de

    2000-01-01

    Full Text Available OBJETIVO: Verificar a ocorrência de Staphylococcus aureus em uma amostra de queijo tipo Minas "frescal" comercializado na cidade de Poços de Caldas, MG, de modo a obter subsídios que permitam avaliar o risco potencial que este produto pode representar para a saúde da população consumidora. MÉTODOS: Foi investigada a presença e o número de cepas de Staphylococcus aureus em 80 amostras de queijo tipo Minas "frescal" produzido artesanalmente e comercializado na cidade de Poços de Caldas, MG, Brasil. RESULTADOS: Os resultados obtidos evidenciaram a presença de S. aureus em 40 (50,0% amostras, cujas contagens revelaram valores médios em torno de 10(5/g. CONCLUSÕES: Tais achados parecem ser extremamente preocupantes, pois além de se situarem acima do limite máximo de 10³/g estabelecido pelo Ministério da Saúde, estes valores mostraram-se muito próximos dos requeridos para a produção de enterotoxinas em quantidades suficientes para a ocorrência de surtos de intoxicação alimentar estafilocócica.

  8. Nanoscale Plasma Coating Inhibits Formation of Staphylococcus aureus Biofilm.

    Science.gov (United States)

    Xu, Yuanxi; Jones, John E; Yu, Haiqing; Yu, Qingsong; Christensen, Gordon D; Chen, Meng; Sun, Hongmin

    2015-12-01

    Staphylococcus aureus commonly infects medical implants or devices, with devastating consequences for the patient. The infection begins with bacterial attachment to the device, followed by bacterial multiplication over the surface of the device, generating an adherent sheet of bacteria known as a biofilm. Biofilms resist antimicrobial therapy and promote persistent infection, making management difficult to futile. Infections might be prevented by engineering the surface of the device to discourage bacterial attachment and multiplication; however, progress in this area has been limited. We have developed a novel nanoscale plasma coating technology to inhibit the formation of Staphylococcus aureus biofilms. We used monomeric trimethylsilane (TMS) and oxygen to coat the surfaces of silicone rubber, a material often used in the fabrication of implantable medical devices. By quantitative and qualitative analysis, the TMS/O2 coating significantly decreased the in vitro formation of S. aureus biofilms; it also significantly decreased in vivo biofilm formation in a mouse model of foreign-body infection. Further analysis demonstrated TMS/O2 coating significantly changed the protein adsorption, which could lead to reduced bacterial adhesion and biofilm formation. These results suggest that TMS/O2 coating can be used to effectively prevent medical implant-related infections. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Predictors of Staphylococcus aureus Colonization and Results after Decolonization

    Directory of Open Access Journals (Sweden)

    Tennison L. Malcolm

    2016-01-01

    Full Text Available Protocols for the screening and decolonization of Staphylococcus aureus prior to total joint arthroplasty (TJA have become widely adopted. The goals of this study were to determine: (1 whether implementation of a screening protocol followed by decolonization with mupirocin/vancomycin and chlorhexidine reduces the risk of revision compared with no screening protocol (i.e., chlorhexidine alone and (2 whether clinical criteria could reliably predict colonization with MSSA and/or MRSA. Electronic medical records of primary patients undergoing TJA that were screened (n=3,927 and were not screened (n=1,751 for Staphylococcus aureus at least 4 days prior to surgery, respectively, were retrospectively reviewed. All patients received chlorhexidine body wipes preoperatively. Patients carrying MSSA and MRSA were treated preoperatively with mupirocin and vancomycin, respectively, along with the standard preoperative antibiotics and chlorhexidine body wipes. Screened patients were 50% less likely to require revision due to prosthetic joint infection compared to those not screened (p=0.04. Multivariate regression models were poorly accurate in predicting colonization with MSSA (AUC = 0.58 and MRSA (AUC = 0.62. These results support the routine screening and decolonization of S. aureus prior to TJA.

  10. [Genotypic and phenotypic analysis of hemolysis in foodborne Staphylococcus aureus].

    Science.gov (United States)

    Wei, Peinan; Lü, Guoping; Xu, Baohong

    2012-11-01

    To establish a multiplex PCR method for detecting genes of (alpha-hemolysin (hla), beta-hemolysin (hlb), hemolysin and 16S rDNA, and to learn the distribution of three hemolysin genes and the characteristics of hemolytic phenotype in 148 foodborne Staphylococcus aureus strains, and to classify the strains with cluster analysis. The multiplex PCR method was established and used to detect the genes of alpha-hemolysin, beta-hemolysin, hemolysin and 16S rDNA. The blood agar method was used to detect the characteristics of hemolytic phenotype. The experiment data was analyed with SPSS16.0. 131 strains were positive for hla gene (88.51%), 90 hlb gene (60.81%), 28 hemolysin gene (18.92%). 131 strains had the characteristics of hemolysis (88.51%), while the hemolysis were negative in 17 strains (11.49%). With the clustering factors of the hemolysin genotype and hemolytic phenotype, 148 strains were classified into 12 types from type A to type L with 100% similarity. Among them, type A contained 58 strains (39.19%), type B 37 (25.00%), type C 18 (12.16%). This multiplex PCR method is fast, convenient and specific, and could be used for high-throughput screening of hemolysin genes in S. aureus. Most of the foodborne Staphylococcus aureus strains carrying the hla gene mainly belong to type A and type B.

  11. Ocorrência de Staphylococcus aureus em queijo tipo "frescal"

    Directory of Open Access Journals (Sweden)

    Edvaldo Sampaio de Almeida Filho

    2000-12-01

    Full Text Available OBJETIVO: Verificar a ocorrência de Staphylococcus aureus em uma amostra de queijo tipo Minas "frescal" comercializado na cidade de Poços de Caldas, MG, de modo a obter subsídios que permitam avaliar o risco potencial que este produto pode representar para a saúde da população consumidora. MÉTODOS: Foi investigada a presença e o número de cepas de Staphylococcus aureus em 80 amostras de queijo tipo Minas "frescal" produzido artesanalmente e comercializado na cidade de Poços de Caldas, MG, Brasil. RESULTADOS: Os resultados obtidos evidenciaram a presença de S. aureus em 40 (50,0% amostras, cujas contagens revelaram valores médios em torno de 10(5/g. CONCLUSÕES: Tais achados parecem ser extremamente preocupantes, pois além de se situarem acima do limite máximo de 10³/g estabelecido pelo Ministério da Saúde, estes valores mostraram-se muito próximos dos requeridos para a produção de enterotoxinas em quantidades suficientes para a ocorrência de surtos de intoxicação alimentar estafilocócica.

  12. Distinctive cytokines as biomarkers predicting fatal outcome of severe Staphylococcus aureus bacteremia in mice.

    Science.gov (United States)

    van den Berg, Sanne; Laman, Jon D; Boon, Louis; ten Kate, Marian T; de Knegt, Gerjo J; Verdijk, Rob M; Verbrugh, Henri A; Nouwen, Jan L; Bakker-Woudenberg, Irma A J M

    2013-01-01

    Invasive Staphylococcus aureus infections are frequently associated with bacteraemia. To support clinical decisions on antibiotic therapy, there is an urgent need for reliable markers as predictors of infection outcome. In the present study in mice, bacteraemia was established by intravenous inoculation of a clinical S. aureus isolate at the LD50 inoculum. As potential biomarkers for fatal outcome, blood culture (qualitative and quantitative), serum levels of C-reactive protein (CRP), as well as 31 selected cytokines and chemokines were assessed during the first three days of infection. A positive S. aureus blood culture, the quantitative blood culture, CRP levels, and levels of eight cytokines were indicative for the presence of S. aureus bacteraemia. However, only tumor necrosis factor (TNF) α, interleukin (IL) 1α, and keratinocyte chemoattractant (KC; a functional homologue of human IL-8) were each significantly elevated in eventually non-surviving infected mice versus eventually surviving infected mice. In severe S. aureus bacteraemia in mice, TNF-α, IL-1α, and KC are biomarkers predicting fatal outcome of infection. KC was a biomarker elevated irrespective the progression of infection, which is very interesting regarding clinical application in view of the heterogeneity of patients experiencing bacteraemia in this respect.

  13. High Prevalence of Methicillin-Resistant Staphylococcus aureus among Patients with Septic Arthritis Caused by Staphylococcus aureus.

    Science.gov (United States)

    Lin, Wei-Ting; Wu, Chung-Da; Cheng, Shun-Chien; Chiu, Chong-Chi; Tseng, Chi-Chou; Chan, Huan-Tee; Chen, Po-Yih; Chao, Chien-Ming

    2015-01-01

    This study investigated the clinical characteristics of patients with septic arthritis caused by Staphylococcus aureus and tried to identify the risk factors for methicillin-resistant S. aureus (MRSA) arthritis. Between January 2008 and December 2011, patients with septic arthritis caused by S. aureus were identified from the computerized databases of a regional hospital and a medical center in southern Taiwan. The medical records of these patients were retrospectively reviewed. A total of 93 patients with S. aureus arthritis were identified, and MRSA arthritis was found in 38 (40.9%) cases. The mean age of the patients was 58 years, and 86 (92.5%) episodes were classified as community-acquired infections. Diabetes mellitus (n = 41, 44.1%) was the most common underlying disease, followed by chronic kidney disease and liver cirrhosis. Patients with MRSA arthritis were more frequently elderly and found in the setting of healthcare-associated infection than patients with methicillin-susceptible S. aureus (MSSA) infections. No other significant differences in clinical manifestations and outcomes were noted between these two groups of patients. Overall, the in-hospital mortality rate was 5.4%, and diabetes mellitus was the only risk factor for mortality. MRSA is emerging in the setting of community-acquired septic arthritis. MRSA septic arthritis is more likely to develop in the elderly and in healthcare-associated infections than MSSA septic arthritis.

  14. Nasal Carriage of Staphylococcus aureus among Children in the Ashanti Region of Ghana.

    Directory of Open Access Journals (Sweden)

    Daniel Eibach

    Full Text Available Nasal carriage with Staphylococcus aureus is a common risk factor for invasive infections, indicating the necessity to monitor prevalent strains, particularly in the vulnerable paediatric population. This surveillance study aims to identify carriage rates, subtypes, antimicrobial susceptibilities and virulence markers of nasal S. aureus isolates collected from children living in the Ashanti region of Ghana.Nasal swabs were obtained from children < 15 years of age on admission to the Agogo Presbyterian Hospital between April 2014 and January 2015. S. aureus isolates were characterized by their antimicrobial susceptibility, the presence of genes encoding for Panton-Valentine leukocidin (PVL and toxic shock syndrome toxin-1 (TSST-1 and further differentiated by spa-typing and multi-locus-sequence-typing.Out of 544 children 120 (22.1% were colonized with S. aureus, with highest carriage rates during the rainy seasons (27.2%; p = 0.007, in females aged 6-8 years (43.7% and males aged 8-10 years (35.2%. The 123 isolates belonged to 35 different spa-types and 19 sequence types (ST with the three most prevalent spa-types being t355 (n = 25, t84 (n = 18, t939 (n = 13, corresponding to ST152, ST15 and ST45. Two (2% isolates were methicillin-resistant S. aureus (MRSA, classified as t1096 (ST152 and t4454 (ST45, and 16 (13% were resistant to three or more different antimicrobial classes. PVL and TSST-1 were detected in 71 (58% and 17 (14% isolates respectively.S. aureus carriage among Ghanaian children seems to depend on age, sex and seasonality. While MRSA rates are low, the high prevalence of PVL is of serious concern as these strains might serve not only as a source for severe invasive infections but may also transfer genes, leading to highly virulent MRSA clones.

  15. Biofilm-forming ability profiling of Staphylococcus aureus and Staphylococcus epidermidis mastitis isolates

    DEFF Research Database (Denmark)

    Oliveira, M; Bexiga, R; Nunes, S F

    2006-01-01

    Biofilm-forming ability has been increasingly recognized as an important virulence factor in Staphylococci, facilitating their persistence in the host, evading its defences and allowing bacterial survival at high antimicrobial concentrations. Staphylococcus aureus remains a major pathogen...... of chronic mastitis, but in the last years Staphylococcus epidermidis has emerged as a relevant mastitis pathogen. The present work aimed at the evaluation of the biofilm-forming ability of Staphylococci field isolates from bovine subclinical mastitis and at the development of a fluorescent in situ...... hybridisation (FISH) protocol that would allow the direct observation of biofilm formation in milk samples. The analysis of phenotypic expression in Congo Red Agar (CRA) and by FISH, showed that 37.5% of the S. aureus isolates produced biofilm, while by optical density measurement only 18.75% isolates revealed...

  16. New epidemiology of Staphylococcus aureus infection in Asia.

    Science.gov (United States)

    Chen, C-J; Huang, Y-C

    2014-07-01

    Not only is Asia the most populous region in the world, but inappropriate therapy, including self-medication with over-the-counter antimicrobial agents, is a common response to infectious diseases. The high antibiotic selective pressure among the overcrowded inhabitants creates an environment that is suitable for the rapid development and efficient spread of numerous multidrug-resistant pathogens. Indeed, Asia is among the regions with the highest prevalence rates of healthcare-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) and community-associated methicillin-resistant S. aureus (CA-MRSA) in the world. Most hospitals in Asia are endemic for multidrug-resistant methicillin-resistant S. aureus (MRSA), with an estimated proportion from 28% (in Hong Kong and Indonesia) to >70% (in Korea) among all clinical S. aureus isolates in the early 2010s. Isolates with reduced susceptibility or a high level of resistance to glycopeptides have also been increasingly identified in the past few years. In contrast, the proportion of MRSA among community-associated S. aureus infections in Asian countries varies markedly, from 35%. Two pandemic HA-MRSA clones, namely multilocus sequence type (ST) 239 and ST5, are disseminated internationally in Asia, whereas the molecular epidemiology of CA-MRSA in Asia is characterized by clonal heterogeneity, similar to that in Europe. In this review, the epidemiology of S. aureus in both healthcare facilities and communities in Asia is addressed, with an emphasis on the prevalence, clonal structure and antibiotic resistant profiles of the MRSA strains. The novel MRSA strains from livestock animals have been considered to constitute a public health threat in western countries. The emerging livestock-associated MRSA strains in Asia are also included in this review. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

  17. UJI BIOAKTIVITAS FORBAZOL E TERHADAP HAMBATAN PERTUMBUHAN PADA STAPHYLOCOCCUS AUREUS

    Directory of Open Access Journals (Sweden)

    Ni Putu Ristiati

    2015-05-01

    Full Text Available Forbazol E dapat disintesis dari 1-(p-tosil pirol-2-karbonil klorida dan fenasil amonium klorida dengan rendeman cukup tinggi melalui empat tahap reaksi yaitu : pertama, reaksi penggabungan; kedua, siklodehidrasi; ketiga,hidrolisis; dan keempat, klorinasi. Staphylococcus aureus merupakan bakteri gram positif. Untuk itu perlu diteliti : (a forbazol E dapat menghambat pertumbuhan S. aureus ; (b konsentrasi forbazol E 75 mg/L akan menimbulkan hambatan pertumbuhan S. aureus lebih tinggi dari konsentrasi 37,5 mg/L. Penelitian eksperimental ini menggunakan rancangan the randomized- posttest-only control group design dan melibatkan 9 sampel pada kelompok kontrol, 9 sampel pada kelompok perlakuan I dan 9 sampel pada perlakuan II. Data yang diperoleh dianalisis dengan menggunakan uji anova pada taraf signifikansi 5%. Hasil penelitian membuktikan forbazol E dapat menghambat pertumbuhan, pemberian  forbazol E pada  pada kelompok perlakuan II dengan konsentrasi 75 mg/L menimbulkan    hambatan     pertumbuhan    S. aureus lebih    tinggi dibandingkan dengan kelompok perlakuan I dengan konsentrasi 37,5 mg/L (p<0,05, uji lanjutan dengan uji beda nyata terkecil (BNT pada taraf  signifikansi  5% diperoleh  bahwa  hambatan  pertumbuhan S. aureus pada kelompok perlakuan II (75 mg/L berbeda bermakna dengan kelompok perlakuan I (37,5 mg/L (p<0,05. Bertolak dari pembahasan di atas dapat disimpulkan bahwa bioaktivitas forbazol E dapat menghambat pertumbuhan   S. aureus.

  18. Colonization of nursing professionals by Staphylococcus aureus La colonización de los profesionales de enfermería por Staphylococcus aureus A colonização dos profissionais de enfermagem por Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Josely Pinto de Moura

    2011-04-01

    Full Text Available This cross-sectional study aimed to investigate the presence of Staphylococcus aureus in the saliva of the nursing team of a teaching hospital in the interior of São Paulo State. Three saliva samples were collected from 351 individuals with an interval of two months between each collection. All ethical aspects were considered. In 867 (82.3% cultures there was no identification of Staphylococcus aureus in the saliva, in 88 (17.7% cultures Staphylococcus aureus was isolated, 26 (2.5% of which were resistant to methicillin. The prevalence of professionals colonized by Staphylococcus aureus was 41.0% (144/351, of which 7.1% (25/351 were characterized as methicillin-resistant Staphylococcus aureus. Transient carriers represented 81.2% and persistent carriers 18.8%. Resistance to mupirocin was 73.1% of MRSA and 9.3% of MSSA. The results demonstrate that it is the nurse and nursing technician that are the professional categories most susceptible to MRSA. Broader discussion on the thematic and interventions are needed.Se trata de un estudio transversal que tuvo como objetivo investigar la presencia de Staphylococcus aureus en la saliva del equipo de enfermería de un hospital escuela del interior del estado de Sao Paulo. Fueron recolectadas tres muestras de saliva de 351 individuos con intervalo de dos meses. Todos los aspectos éticos fueron contemplados. En 867 (82,3% culturas no hubo identificación de Staphylococcus aureus en la saliva, en 88 (17,7% culturas fue aislado Staphylococcus aureus, siendo 26 (2,5% resistentes a la meticilina. La prevalencia de profesionales colonizados por Staphylococcus aureus fue de 41,0% (144/351, de los cuales 7,1% (25/351 fueron caracterizados como Staphylococcus aureus resistentes a la meticilina. Los portadores transitorios representaron 81,2% y los persistentes 18,8%. La resistencia a la mupirocina fue de 73,1% entre los resistentes a la meticilina y 9,3% en los sensibles a la meticilina. Los resultados

  19. Staphylococcus aureus detection in the mouth of housekeepers Detección de Staphylococcus aureus en la boca de trabajadores de la limpieza hospitalaria Detecção de Staphylococcus aureus na boca de trabalhadores da limpeza hospitalar

    Directory of Open Access Journals (Sweden)

    Elaine Drehmer de Almeida Cruz

    2011-02-01

    Full Text Available This study assessed the prevalence of colonization by Staphylococcus aureus in hospital housekeepers, and their knowledge and beliefs regarding this problem. Three saliva samples were collected and a questionnaire regarding knowledge and beliefs was applied. Of the 92 workers, 63 (68.5% participated in the study; 20 were not and 43 were colonized; 13 by methicillin resistant Staphylococcus aureus and 30 by methicillin sensitive Staphylococcus aureus. Persistent carrier status of methicillin resistant Staphylococcus aureus was detected in 15.4% of cases. Low knowledge and perception of occupational risk were observed. The mouth was identified as an important reservoir of methicillin resistant Staphylococcus aureus. Analyzing knowledge and beliefs, as well as the state of carrier, is an important strategy to be added to educational actions for the prevention of workers' colonization.Este estudio evaluó la prevalencia de la colonización por Staphylococcus aureus en trabajadores de limpieza hospitalaria, y su conocimiento y creencias acerca de la problemática. Fueron recolectadas tres muestras de saliva y aplicado un cuestionario referente al conocimiento y creencias. De 92 trabajadores, 63 (68,5% participaron del estudio; 20 se presentaron no colonizados y 43 colonizados; 13 para Staphylococcus aureus resistente a la meticilina y 30 para Staphylococcus aureus sensibles a la meticilina. El estado de portador persistente por Staphylococcus aureus resistente a la meticilina fue detectado en 15,4% de los casos. Bajo conocimiento y percepción del riesgo ocupacional fueron observados. La boca fue identificada como importante reservatorio de Staphylococcus aureus resistente a la meticilina. Analizar el conocimiento y creencias juntamente con la investigación del estado de portador es una importante estrategia a ser agregada a las acciones educativas para la prevención de la colonización de trabajadores.Este estudo avaliou a prevalência da coloniza

  20. Low efficacy of tobramycin in experimental Staphylococcus aureus endocarditis

    DEFF Research Database (Denmark)

    Lerche, C. J.; Christophersen, L. J.; Trøstrup, H.

    2015-01-01

    The empiric treatment of infective endocarditis (IE) varies widely and, in some places, a regimen of penicillin in combination with an aminoglycoside is administered. The increasing incidence of Staphylococcus aureus IE, poor tissue penetration by aminoglycosides and low frequency of penicillin...... into untreated (n = 22) or tobramycin-treated (n = 13) groups. The treatment group received tobramycin once-daily. Animals were evaluated at 1 day post infection (DPI), 2 DPI or 3 DPI. Quantitative bacteriology and cytokine expression were measured for valves, myocardium and serum. A decrease of bacterial load...... was observed at 2 DPI (p ≤ 0.001) but not at 3 DPI. Tobramycin as functional monotherapy only reduced bacterial load and inflammation transiently, and was insufficient in most cases of S. aureus IE....

  1. Treatment of methicillin-resistant Staphylococcus aureus in Latin America

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    Carlos M Luna

    Full Text Available The global spread of methicillin-resistant Staphylococcus aureus (MRSA means it is now a pathogen of worldwide public health concern. Within Latin America, MRSA is highly prevalent, with the proportion of S. aureus isolates that are methicillin-resistant on the rise, yet resources for managing the infection are limited. While several guidelines exist for the treatment of MRSA infections, many are written for the North American or European setting and need adaptation for use in Latin America. In this article, we aim to emphasize the importance of appropriate treatment of MRSA in the healthcare and community settings of Latin America. We present a summary of the available guidelines and antibiotics, and discuss particular considerations for clinicians treating MRSA in Latin America

  2. Staphylococcus aureus Infections: Epidemiology, Pathophysiology, Clinical Manifestations, and Management

    Science.gov (United States)

    Davis, Joshua S.; Eichenberger, Emily; Holland, Thomas L.

    2015-01-01

    SUMMARY Staphylococcus aureus is a major human pathogen that causes a wide range of clinical infections. It is a leading cause of bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device-related infections. This review comprehensively covers the epidemiology, pathophysiology, clinical manifestations, and management of each of these clinical entities. The past 2 decades have witnessed two clear shifts in the epidemiology of S. aureus infections: first, a growing number of health care-associated infections, particularly seen in infective endocarditis and prosthetic device infections, and second, an epidemic of community-associated skin and soft tissue infections driven by strains with certain virulence factors and resistance to β-lactam antibiotics. In reviewing the literature to support management strategies for these clinical manifestations, we also highlight the paucity of high-quality evidence for many key clinical questions. PMID:26016486

  3. Methicillin-resistant Staphylococcus aureus, Hawaii, 2000–2002

    Science.gov (United States)

    Park, Sarah Y.; Ayers, Tracy L.; Miller, F. DeWolfe; MacFadden, Ralph; Nakata, Michele; Lee, Myra Ching; Effler, Paul V.

    2005-01-01

    The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has generated considerable concern among medical and public health professionals. We used a statewide, population-based antimicrobial resistance surveillance system to examine epidemiologic trends for MRSA from outpatients and inpatients in Hawaii. Pediatric and adult patient populations were compared to assess characteristics of MRSA isolates specific for each group. From 2000 to 2002, 8,206 (26%) of 31,482 total S. aureus isolates were MRSA. During this period, the proportion of MRSA isolates increased in both outpatient and inpatient clinical settings (p0.05). Although MRSA isolates from adults demonstrated high resistance to most non–β-lactams, most MRSA isolates from pediatric outpatients remained susceptible to most non–β-lactams. PMID:16102308

  4. Cavity Forming Pneumonia Due to Staphylococcus aureus Following Dengue Fever.

    Science.gov (United States)

    Miyata, Nobuyuki; Yoshimura, Yukihiro; Tachikawa, Natsuo; Amano, Yuichiro; Sakamoto, Yohei; Kosuge, Youko

    2015-11-01

    While visiting Malaysia, a 22-year-old previously healthy Japanese man developed myalgia, headache, and fever, leading to a diagnosis of classical dengue fever. After improvement and returning to Japan after a five day hospitalization, he developed productive cough several days after defervescing from dengue. Computed tomography (CT) thorax scan showed multiple lung cavities. A sputum smear revealed leukocytes with phagocytized gram-positive cocci in clusters, and grew an isolate Staphylococcus aureus sensitive to semi-synthetic penicillin; he was treated successfully with ceftriaxone and cephalexin. This second reported case of pneumonia due to S. aureus occurring after dengue fever, was associated both with nosocomial exposure and might have been associated with dengue-associated immunosuppression. Clinicians should pay systematic attention to bacterial pneumonia following dengue fever to establish whether such a connection is causally associated. © The American Society of Tropical Medicine and Hygiene.

  5. Community-Associated Methicillin-Resistant Staphylococcus aureus Case Studies

    Science.gov (United States)

    Sowash, Madeleine G.; Uhlemann, Anne-Catrin

    2014-01-01

    Over the past decade, the emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has changed the landscape of S. aureus infections around the globe. Initially recognized for its ability to cause disease in young and healthy individuals without healthcare exposures as well as for its distinct genotype and phenotype, this original description no longer fully encompasses the diversity of CA-MRSA as it continues to expand its niche. Using four case studies, we highlight a wide range of the clinical presentations and challenges of CA-MRSA. Based on these cases we further explore the globally polygenetic background of CA-MRSA with a special emphasis on generally less characterized populations. PMID:24085688

  6. Methicillin-resistant Staphylococcus aureus in human milk

    Directory of Open Access Journals (Sweden)

    FR Novak

    2000-01-01

    Full Text Available We collected and analyzed 500 samples of human milk, from five Brazilian cities (100 from each to detect methicillin-resistant strains of Staphylococcus aureus (MRSA producing enterotoxins. We found 57 strains of MRSA, and the mecA gene, responsible for resistance, was detected in all of them using a specific molecular probe. We examined 40 strains for the presence of four enterotoxins, after selecting a subset that included all strains from each region, except for the largest sample, from which 10 were randomly selected. Among these two presented enterotoxin B, and growth in human colostrum and trypicase soy broth. After 5 h of incubation at 37°C, population sizes were already higher than 9.4 x 105 UFC/ml and enterotoxin was released into culture medium and colostrum. Our results stress the importance of hygiene, sanitary measures, and appropriate preservation conditions to avoid the proliferation of S. aureus in human milk.

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

    DEFF Research Database (Denmark)

    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...... outbreaks and is endemic in 10 nursing homes. Five staff members from nursing homes have been infected with MRSA. MRSA commonly causes skin and soft tissue infections (76%), but serious infections such as septicaemia and pneumonia are also found. CONCLUSION: Treatment of MRSA-infected patients is costly due...

  8. Staphylococcus aureus redirects central metabolism to increase iron availability.

    Directory of Open Access Journals (Sweden)

    David B Friedman

    2006-08-01

    Full Text Available Staphylococcus aureus pathogenesis is significantly influenced by the iron status of the host. However, the regulatory impact of host iron sources on S. aureus gene expression remains unknown. In this study, we combine multivariable difference gel electrophoresis and mass spectrometry with multivariate statistical analyses to systematically cluster cellular protein response across distinct iron-exposure conditions. Quadruplicate samples were simultaneously analyzed for alterations in protein abundance and/or post-translational modification state in response to environmental (iron chelation, hemin treatment or genetic (Deltafur alterations in bacterial iron exposure. We identified 120 proteins representing several coordinated biochemical pathways that are affected by changes in iron-exposure status. Highlighted in these experiments is the identification of the heme-regulated transport system (HrtAB, a novel transport system which plays a critical role in staphylococcal heme metabolism. Further, we show that regulated overproduction of acidic end-products brought on by iron starvation decreases local pH resulting in the release of iron from the host iron-sequestering protein transferrin. These findings reveal novel strategies used by S. aureus to acquire scarce nutrients in the hostile host environment and begin to define the iron and heme-dependent regulons of S. aureus.

  9. Coordination of Chromosome Segregation and Cell Division in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Amy L. Bottomley

    2017-08-01

    Full Text Available Productive bacterial cell division and survival of progeny requires tight coordination between chromosome segregation and cell division to ensure equal partitioning of DNA. Unlike rod-shaped bacteria that undergo division in one plane, the coccoid human pathogen Staphylococcus aureus divides in three successive orthogonal planes, which requires a different spatial control compared to rod-shaped cells. To gain a better understanding of how this coordination between chromosome segregation and cell division is regulated in S. aureus, we investigated proteins that associate with FtsZ and the divisome. We found that DnaK, a well-known chaperone, interacts with FtsZ, EzrA and DivIVA, and is required for DivIVA stability. Unlike in several rod shaped organisms, DivIVA in S. aureus associates with several components of the divisome, as well as the chromosome segregation protein, SMC. This data, combined with phenotypic analysis of mutants, suggests a novel role for S. aureus DivIVA in ensuring cell division and chromosome segregation are coordinated.

  10. Mechanisms of resistance to daptomycin in Staphylococcus aureus.

    Science.gov (United States)

    Gómez Casanova, N; Siller Ruiz, M; Muñoz Bellido, J L

    2017-12-01

    Daptomycin is a cyclic lipopeptide active against multidrug-resistant Gram-positives, including methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus with reduced susceptibility to vancomycin. It is 4-8 fold as active as vancomycin against methicillin-susceptible S. aureus (MSSA) and MRSA, and retains most of this activity against S. aureus with reduced susceptibility to vancomycin. The mechanism of action of daptomycin is not fully understood. Daptomycin binds to the bacterial cytoplasmic membrane, leading to depolarization due to the loss of potassium ions from the cytoplasm. Daptomycin non-susceptibility is unusual in the clinical setting. Different mechanisms have been proposed to explain daptomycin-resistance, most of them associated to changes in composition, charge and fluidity of the cell wall. The mprF mutations, which lead to an increase in the lysyl-phosphatidyl glycerol production, and rpoB and rpoC mutations (rpo genes encode for bacterial RNA polymerase subunits) have been proposed as associated to daptomycin-resistance, but a number of mutations in other genes ( walK, cls, ggrA…) have been proposed.

  11. Vaccine Protection of Leukopenic Mice against Staphylococcus aureus Bloodstream Infection

    Science.gov (United States)

    Rauch, Sabine; Gough, Portia; Kim, Hwan Keun; Schneewind, Olaf

    2014-01-01

    The risk for Staphylococcus aureus bloodstream infection (BSI) is increased in immunocompromised individuals, including patients with hematologic malignancy and/or chemotherapy. Due to the emergence of antibiotic-resistant strains, designated methicillin-resistant S. aureus (MRSA), staphylococcal BSI in cancer patients is associated with high mortality; however, neither a protective vaccine nor pathogen-specific immunotherapy is currently available. Here, we modeled staphylococcal BSI in leukopenic CD-1 mice that had been treated with cyclophosphamide, a drug for leukemia and lymphoma patients. Cyclophosphamide-treated mice were highly sensitive to S. aureus BSI and developed infectious lesions lacking immune cell infiltrates. Virulence factors of S. aureus that are key for disease establishment in immunocompetent hosts—α-hemolysin (Hla), iron-regulated surface determinants (IsdA and IsdB), coagulase (Coa), and von Willebrand factor binding protein (vWbp)—are dispensable for the pathogenesis of BSI in leukopenic mice. In contrast, sortase A mutants, which cannot assemble surface proteins, display delayed time to death and increased survival in this model. A vaccine with four surface antigens (ClfA, FnBPB, SdrD, and SpAKKAA), which was identified by genetic vaccinology using sortase A mutants, raised antigen-specific immune responses that protected leukopenic mice against staphylococcal BSI. PMID:25183728

  12. Architecture of a Species: Phylogenomics of Staphylococcus aureus.

    Science.gov (United States)

    Planet, Paul J; Narechania, Apurva; Chen, Liang; Mathema, Barun; Boundy, Sam; Archer, Gordon; Kreiswirth, Barry

    2017-02-01

    A deluge of whole-genome sequencing has begun to give insights into the patterns and processes of microbial evolution, but genome sequences have accrued in a haphazard manner, with biased sampling of natural variation that is driven largely by medical and epidemiological priorities. For instance, there is a strong bias for sequencing epidemic lineages of methicillin-resistant Staphylococcus aureus (MRSA) over sensitive isolates (methicillin-sensitive S. aureus: MSSA). As more diverse genomes are sequenced the emerging picture is of a highly subdivided species with a handful of relatively clonal groups (complexes) that, at any given moment, dominate in particular geographical regions. The establishment of hegemony of particular clones appears to be a dynamic process of successive waves of replacement of the previously dominant clone. Here we review the phylogenomic structure of a diverse range of S. aureus, including both MRSA and MSSA. We consider the utility of the concept of the 'core' genome and the impact of recombination and horizontal transfer. We argue that whole-genome surveillance of S. aureus populations could lead to better forecasting of antibiotic resistance and virulence of emerging clones, and a better understanding of the elusive biological factors that determine repeated strain replacement. Copyright © 2016. Published by Elsevier Ltd.

  13. Human Staphylococcus aureus lineages among Zoological Park residents in Greece

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    E. Drougka

    2015-10-01

    Full Text Available Staphylococcus aureus is a part of the microbiota flora in many animal species. The clonal spread of S. aureus among animals and personnel in a Zoological Park was investigated. Samples were collected from colonized and infected sites among 32 mammals, 11 birds and eight humans. The genes mecA, mecC, lukF/lukS-PV (encoding Panton-Valentine leukocidin, PVL and tst (toxic shock syndrome toxin-1 were investigated by PCR. Clones were defined by Multilocus Sequence Typing (MLST, spa type and Pulsed-Field Gel Electrophoresis (PFGE. Seven S. aureus isolates were recovered from four animals and one from an employee. All were mecA, mecC and tst–negative, whereas, one carried the PVL genes and was isolated from an infected Squirrel monkey. Clonal analysis revealed the occurrence of seven STs, eight PFGE and five spa types including ones of human origin. Even though a variety of genotypes were identified among S. aureus strains colonizing zoo park residents, our results indicate that colonization with human lineages has indeed occurred.

  14. Analisis Cemaran Staphylococcus aureus pada Gelas, Darah Segar, dan Jamu dengan Ramuan Darah Ular Kobra Jawa (Naja sputatrix

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    Roza Azizah Primatika

    2017-01-01

    rerata cemaran Staphylococcus aureus menunjukkan tidak ada perbedaan antara swab gelas, darah dan ramuan darah ular kobra. Walaupun demikian, jamu yang mengandung darah ular kobra berpotensi mengandung Staphylococcus aureus yang membahayakan konsumen.

  15. Differentiation between Staphylococcus aureus and Staphylococcus epidermidis strains using Raman spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Rebrošová, K.; Šiler, Martin; Samek, Ota; Růžička, F.; Bernatová, Silvie; Ježek, Jan; Zemánek, Pavel; Holá, V.

    2017-01-01

    Roč. 12, č. 10 (2017), s. 881-890 ISSN 1746-0913 R&D Projects: GA ČR(CZ) GA15-20645S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : Raman spectroscopy * rapid diagnostics * Staphylococcus epidermidis * Staphyococcus aureus Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 3.374, year: 2016

  16. Monitoring of abdominal Staphylococcus aureus infection using magnetic resonance imaging

    DEFF Research Database (Denmark)

    Kromrey, M L; Göhler, A; Friedrich, N

    2017-01-01

    To establish a routine workflow for in vivo magnetic resonance imaging (MRI) of mice infected with bacterial biosafety level 2 pathogens and to generate a mouse model for systemic infection with Staphylococcus aureus suitable for monitoring by MRI. A self-contained acrylic glass animal bed...... visualized using a standard T2-weighted scan. Infection monitoring was performed for each animal by measurements at 1, 3, and 7 days after infection. Intravenous pathogen application led to a dose-dependent decrease in survival probability (p = 0.03). In the group with the highest infectious dose the 7-day...

  17. Antibacterial activity of alimentary plants against Staphylococcus aureus growth.

    Science.gov (United States)

    Pérez, C; Anesini, C

    1994-01-01

    Alimentary plants were screened for antibacterial activity against a penicillin G resistant strain of Staphylococcus aureus. Twenty-five samples of plant material corresponding to 21 species from 13 families were used. Both aqueous and ethanol extracts were obtained from them. Antibacterial activity was determined by the agar-well diffusion method, using cephazolin as a standard antibiotic. Seventeen ethanol extracts were found active. Eugenia caryophyllata (clavo de olor*) flowers, Myristica fragans (nuez moscada*) seeds, Theobroma cacao (cacao*) seed bark, Triticum sp (trigo*) fruit, Zea mays (maíz*) fruit and Piper nigrum (pimienta*) ripe fruit produced some of the more active extracts (* = Argentine vulgar names).

  18. Serious infections caused by methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Boucher, Helen; Miller, Loren G; Razonable, Raymund R

    2010-09-15

    Although first identified just >4 decades ago, methicillin-resistant Staphylococcus aureus (MRSA) has undergone rapid evolutionary changes and epidemiologic expansion to become a major cause of nosocomial and community-acquired infections worldwide. Increasing resistance to vancomycin among MRSA strains in conjunction with availability of new antibiotics, including daptomycin and linezolid, have increased treatment choices but made clinical treatment decisions more challenging. This article describes the clinical features and management issues of 2 challenging-to-treat manifestations of MRSA infection, bacteremia and/or endocarditis and osteomyelitis. It also presents a brief review of community-associated MRSA infections and preventive strategies directed against MRSA.

  19. Molecular mechanisms of methicillin resistance in Staphylococcus aureus.

    Science.gov (United States)

    Domínguez, M A; Liñares, J; Martín, R

    1997-09-01

    Methicillin-resistant Staphylococcus aureus (MRSA) strains are among the most common nosocomial pathogens. The most significant mechanism of resistance to methicillin in this-species is the acquisition of a genetic determinant (mecA gene). However, resistance seems to have a more complex molecular basis, since additional chromosomal material is involved in such resistance. Besides, overproduction of penicillinase and/or alterations in the PBPs can contribute to the formation of resistance phenotypes. Genetic and environmental factors leading to MRSA are reviewed.

  20. Methicillin-resistant Staphylococcus aureus in North-east Croatia

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    Tajana Pastuović

    2015-05-01

    Full Text Available Objective. The aim of this 5-year study was to determine the frequency and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA-related infections at Osijek Clinical Hospital. Materials and methods. A total of 1987 staphylococci-infected clinical isolates were collected and analysed at the Microbiology Department of the Public Health Institute of Osijek-Baranja County. Results. Between 2008 and 2012, the average rate of MRSA-related infections in staphylococci-infected patients was 27.4%. The proportion of MRSArelated infections on all Staphylococcus aureus (S. aureus isolates from clinical specimens showed a decreasing trend, from 32.6% in 2008 to 25.5% in 2012. MRSA-related infections were mostly detected in wound swabs (50.6% and aspirates (28.8% of patients hospitalized in the surgical (49.8% and intensive care units (27.9%. MRSA-related infection showed an increase compared to S. aureus-infections in samples of wounds and aspirates in 2011 and 2012 (57.9%/34.9% and 35.2%/16.3%, respectively. The majority of strains of MRSA-related infections were resistant to several antibiotics, including erythromycin and clindamycin, where susceptibility were less than 10%. All MRSA isolates were susceptible to vancomycin, teicoplanin and linezolid. Therefore, antibiotic therapies for MRSA infections include vancomycin, teicoplanin and linezolid, but microbiological diagnostics need to be performed in order to know when the use of glycopeptides and oxazolidinones is indicated. Conclusion. Our results suggest that appropriate prevention measures, combined with the more rational use of antibiotics are crucial to reduce the spread of MRSA-related infection in healthcare settings. Further monitoring is necessary of the incidence and antibiotic susceptibility of MRSA-related infections in our community.

  1. Methicillin-resistant Staphylococcus aureus in North-east Croatia.

    Science.gov (United States)

    Pastuović, Tajana; Perić, Magdalena; Bošnjak, Zinka; Ružman, Nataša; Majić, Patricia Reisz; Talapko, Jasminka; Atalić, Vlasta; Loci-Zvocak, Snježana; Vuković, Dubravka

    2015-01-01

    The aim of this 5-year study was to determine the frequency and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA)-related infections at Osijek Clinical Hospital. A total of 1987 staphylococci-infected clinical isolates were collected and analysed at the Microbiology Department of the Public Health Institute of Osijek-Baranja County. Between 2008 and 2012, the average rate of MRSA-related infections in staphylococci-infected patients was 27.4%. The proportion of MRSA-related infections on all Staphylococcus aureus (S. aureus) isolates from clinical specimens showed a decreasing trend, from 32.6% in 2008 to 25.5% in 2012. MRSA-related infections were mostly detected in wound swabs (50.6%) and aspirates (28.8%) of patients hospitalized in the surgical (49.8%) and intensive care units (27.9%). MRSA-related infection showed an increase compared to S. aureus-infections in samples of wounds and aspirates in 2011 and 2012 (57.9%/34.9% and 35.2%/16.3%, respectively). The majority of strains of MRSA-related infections were resistant to several antibiotics, including erythromycin and clindamycin, where susceptibility were less than 10%. All MRSA isolates were susceptible to vancomycin, teicoplanin and linezolid. Therefore, antibiotic therapies for MRSA infections include vancomycin, teicoplanin and linezolid, but microbiological diagnostics need to be performed in order to know when the use of glycopeptides and oxazolidinones is indicated. Our results suggest that appropriate prevention measures, combined with the more rational use of antibiotics are crucial to reduce the spread of MRSA-related infection in healthcare settings. Further monitoring is necessary of the incidence and antibiotic susceptibility of MRSA-related infections in our community. Copyright © 2015 by Academy of Sciences and Arts of Bosnia and Herzegovina.

  2. In silico analysis for identifying potential vaccine candidates against Staphylococcus aureus

    OpenAIRE

    Delfani, Somayeh; Imani Fooladi, Abbas Ali; Mobarez, Ashraf Mohabati; Emaneini, Mohammad; Amani, Jafar; Sedighian, Hamid

    2015-01-01

    Purpose Staphylococcus aureus is one of the most important causes of nosocomial and community-acquired infections. The increasing incidence of multiple antibiotic-resistant S. aureus strains and the emergence of vancomycin resistant S. aureus strains have placed renewed interest on alternative means of prevention and control of infection. S. aureus produces a variety of virulence factors, so a multi-subunit vaccine will be more successful for preventing S. aureus infections than a mono-subuni...

  3. Transmission of Staphylococcus aureus between mothers and infants in an African setting.

    Science.gov (United States)

    Schaumburg, F; Alabi, A S; Mombo-Ngoma, G; Kaba, H; Zoleko, R M; Diop, D A; Mackanga, J-R; Basra, A; Gonzalez, R; Menendez, C; Grobusch, M P; Kremsner, P G; Köck, R; Peters, G; Ramharter, M; Becker, K

    2014-06-01

    Staphylococcus aureus colonization is a risk factor for invasive disease. There is a need to understand S. aureus colonization in infancy as the burden of S. aureus infections in infants is high. We aimed to investigate the transmission of S. aureus between mothers and their newborns during the first year after delivery in an African setting. In a longitudinal cohort study, colonization of Gabonese mother-infant pairs was assessed at delivery and after 1, 9 and 12 months. Swabs were taken from mothers (nares, mammillae) and infants (nares and throat). Isolates were characterized and risk factors for colonization were assessed using a standardized questionnaire. We recruited 311 mothers and 318 infants including seven sets of twins. Maternal and infant colonization rates declined synchronously following a peak after 1 month at 40% (mothers) and 42% (infants). Maternal colonization was a risk factor for S. aureus carriage in infants. Based on spa typing, direct mother-to-infant transmission was evident in 5.6%. Of all methicillin-resistant isolates (n = 9), 44.4% were related to the USA300 clone; 56.7% (n = 261) of all S. aureus carried Panton-Valentine leukocidin encoding genes. Direct mother-to-infant transmission was rare and cannot explain the increase of carriage in infants within the first month. A transmission from external sources is likely and challenges the S. aureus infection control in newborns and infants in an African setting. The detection of USA300-related MRSA fuels the concern about the spread of this clone in Central Africa. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

  4. Staphylococcus aureus complex from animals and humans in three remote African regions

    NARCIS (Netherlands)

    Schaumburg, Frieder; Pauly, Maude; Anoh, Etile; Mossoun, Arsene; Wiersma, Lidewij; Schubert, Grit; Flammen, Arnaud; Alabi, Abraham S.; Muyembe-Tamfum, Jean-Jacques; Grobusch, Martin P.; Karhemere, Stomy; Akoua-Koffi, Chantal; Couacy-Hymann, Emmanuel; Kremsner, Peter G.; Mellmann, Alexander; Becker, Karsten; Leendertz, Fabian H.; Peters, Georg

    2015-01-01

    Staphylococcus schweitzeri has been recently considered to be a highly divergent Staphylococcus aureus clade and usually colonises nonhuman primates and bats in sub-Saharan Africa. Its transmissibility to humans remains unclear. We therefore investigated the transmission of S. aureus and S.

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

    Science.gov (United States)

    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…

  6. Characterization of Staphylococcus aureus Strains Associated with Food Poisoning in Shenzhen, China

    NARCIS (Netherlands)

    Yan, Xiaomei; Wang, Bing; Tao, Xiaoxia; Hu, Qinghua; Cui, Zhigang; Zhang, Jianzhong; Lin, Yiman; You, Yuanhai; Shi, Xiaolu; Grundmann, Hajo

    To characterize isolates of Staphylococcus aureus that were associated with staphylococcal food poisoning between 2006 and 2009 in Shenzhen, Southern China, a total of 52 Staphylococcus aureus isolates from 11 outbreaks were analyzed by using multilocus sequence typing (MLST), spa typing, and

  7. Analysis of the genetic diversity of vancomycin-resistant Staphylococcus aureus Análise da diversidade genética do Staphylococcus aureus resistente à vancomicina

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    Geraldo B. Melo

    2005-06-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA and methicillin-resistant coagulase-negative staphylococci (MRCoNS are among the most frequent causes of hospital infections worldwide, thus justifying the increasing use of vancomycin. In this study, we evaluated the presence of glycopeptide-resistant staphylococci, in 41 patients hospitalized in the Clinical Hospital of the Federal University of Uberlândia in Uberlândia, MG, who were being treated with vancomycin. All isolates were plated on Mueller-Hinton agar containing vancomycin. Vancomycin resistance was confirmed by surface growth after incubation for 24-48 h at 35ºC. Heteroresistance was evaluated by plating with a large inoculum (10(8 CFU/mL. One patient with nephritis who was on a hemodialysis program was diagnosed with the phenotype isolate of vancomycin-intermediate Staphylococcus aureus (VISA (CIM = 8 mug/mL and in eight patients, strains of heteroresistant Staphylococcus corresponding to the hVISA phenotype were isolated. In addition to the extended use of vancomycin, other risk factors associated with the presence of these microorganisms included the use of three or more antimicrobial agents, surgery, and three or more invasive procedures. Molecular analysis by randon amplified polymorphic DNA polymerase chain reaction (RAPD-PCR showed two clusters involving two samples each one of them, in surgical patients, with temporal and spatial relationship and isolates similarity concerning the susceptibility range to antimicrobial agents.Staphylococcus aureus resistente à meticilina (MRSA e Staphylococcus coagulase negativo resistente à meticilina (MRCoNS são os agentes mais freqüentes em infecções hospitalares mundialmente, justificando o incremento no uso de vancomicina. Neste estudo avaliamos a presença de Staphylococcus resistentes aos glicopeptideos em 41 pacientes, em uso de vancomicina, hospitalizados no Hospital de Clínicas da Universidade Federal de Uberlândia em

  8. Methicillin-resistant Staphylococcus aureus in palliative care: A prospective study of Methicillin-resistant Staphylococcus aureus prevalence in a hospital-based palliative care unit.

    Science.gov (United States)

    Schmalz, Oliver; Strapatsas, Tobias; Alefelder, Christof; Grebe, Scott Oliver

    2016-07-01

    Methicillin-resistant Staphylococcus aureus is a common organism in hospitals worldwide and is associated with morbidity and mortality. However, little is known about the prevalence in palliative care patients. Furthermore, there is no standardized screening protocol or treatment for patients for whom therapy concentrates on symptom control. Examining the prevalence of methicillin-resistant Staphylococcus aureus in palliative care patients as well as the level of morbidity and mortality. We performed a prospective study where methicillin-resistant Staphylococcus aureus screening was undertaken in 296 consecutive patients within 48 h after admission to our palliative care unit. Medical history was taken, clinical examination was performed, and the Karnofsky Performance Scale and Palliative Prognostic Score were determined. Prevalence of Methicillin-resistant Staphylococcus aureus was compared to data of general hospital patients. In total, 281 patients were included in the study having a mean age of 69.7 years (standard deviation = 12.9 years) and an average Karnofsky Performance Scale between 30% and 40%. The mean length of stay was 9.7 days (standard deviation = 7.6 days). A total of 24 patients were methicillin-resistant Staphylococcus aureus positive on the first swab. Median number of swabs was 2. All patients with a negative methicillin-resistant Staphylococcus aureus swab upon admission remained Methicillin-resistant Staphylococcus aureus negative in all subsequent swabs. Our study suggests that the prevalence of Methicillin-resistant Staphylococcus aureus among patients in an in-hospital palliative care unit is much higher than in other patient populations. © The Author(s) 2016.

  9. Staphylococcus aureus and Community-Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) in and Around Therapeutic Whirlpools in College Athletic Training Rooms

    Science.gov (United States)

    Kahanov, Leamor; Kim, Young Kyun; Eberman, Lindsey; Dannelly, Kathleen; Kaur, Haninder; Ramalinga, A.

    2015-01-01

    Context: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a leading cause of skin and soft tissue infection in the nonhospitalized community. Care of the athletes in athletic training rooms is specifically designed with equipment tailored to the health care needs of the athletes, yet recent studies indicate that CA-MRSA is still prevalent in athletic facilities and that cleaning methods may not be optimal. Objective: To investigate the prevalence of Staphylococcus aureus and CA-MRSA in and around whirlpools in the athletic training room. Design: Cross-sectional study. Setting: National Collegiate Athletic Association Division I university. Patients or Other Participants: Student-athletes (n = 109) consisting of 46 men (42%) and 63 women (58%) representing 6 sports. Main Outcome Measure(s): Presence of MRSA and Staphylococcus aureus in and around the whirlpool structures relative to sport and number of athletes using the whirlpools. Results: We identified Staphylococcus aureus in 22% (n = 52/240) of the samples and MRSA in 0.8% (n = 2/240). A statistically significant difference existed between the number of athletes using the whirlpool and the presence of Staphylococcus aureus in and around the whirlpools (F2,238 = 2.445, P = .007). However, Staphylococcus aureus was identified regardless of whether multiple athletes used a whirlpool or no athletes used a whirlpool. We did not identify a relationship between the number of athletes who used a whirlpool and Staphylococcus aureus or MRSA density (P = .134). Conclusions: Staphylococcus aureus and MRSA were identified in and around the whirlpools. Transmission of the bacteria can be reduced by following the cleaning and disinfecting protocols recommended by the Centers for Disease Control and Prevention. Athletic trainers should use disinfectants registered by the Environmental Protection Agency to sanitize all whirlpools between uses. PMID:25710853

  10. Staphylococcus aureus and community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in and around therapeutic whirlpools in college athletic training rooms.

    Science.gov (United States)

    Kahanov, Leamor; Kim, Young Kyun; Eberman, Lindsey; Dannelly, Kathleen; Kaur, Haninder; Ramalinga, A

    2015-04-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a leading cause of skin and soft tissue infection in the nonhospitalized community. Care of the athletes in athletic training rooms is specifically designed with equipment tailored to the health care needs of the athletes, yet recent studies indicate that CA-MRSA is still prevalent in athletic facilities and that cleaning methods may not be optimal. To investigate the prevalence of Staphylococcus aureus and CA-MRSA in and around whirlpools in the athletic training room. Cross-sectional study. National Collegiate Athletic Association Division I university. Student-athletes (n = 109) consisting of 46 men (42%) and 63 women (58%) representing 6 sports. Presence of MRSA and Staphylococcus aureus in and around the whirlpool structures relative to sport and number of athletes using the whirlpools. We identified Staphylococcus aureus in 22% (n = 52/240) of the samples and MRSA in 0.8% (n = 2/240). A statistically significant difference existed between the number of athletes using the whirlpool and the presence of Staphylococcus aureus in and around the whirlpools (F(2,238) = 2.445, P = .007). However, Staphylococcus aureus was identified regardless of whether multiple athletes used a whirlpool or no athletes used a whirlpool. We did not identify a relationship between the number of athletes who used a whirlpool and Staphylococcus aureus or MRSA density (P = .134). Staphylococcus aureus and MRSA were identified in and around the whirlpools. Transmission of the bacteria can be reduced by following the cleaning and disinfecting protocols recommended by the Centers for Disease Control and Prevention. Athletic trainers should use disinfectants registered by the Environmental Protection Agency to sanitize all whirlpools between uses.

  11. Response of Staphylococcus Aureus to a Spaceflight Analogue

    Science.gov (United States)

    Castro, S. L.; Ott, C. M.

    2010-01-01

    The decreased gravity of the spaceflight environment creates quiescent, low fluid shear conditions. This environment can impart considerable effects on the physiology of microorganisms as well as their interactions with potential hosts. Using the rotating wall vessel (RWV), as a spaceflight analogue, the consequence of low fluid shear culture on microbial pathogenesis has provided a better understanding of the risks to the astronaut crew from infectious microorganisms. While the outcome of low fluid shear culture has been investigated for several bacterial pathogens, little has been done to understand how this environmental factor affects Staphylococcus aureus. S. aureus is an opportunistic human pathogen which presents a high level of infection risk to the crew, as it has been isolated from both the space shuttle and International Space Station. Given that approximately forty percent of the population are carriers of the bacteria, eradication of this organism from in flight environments is impractical. These reasons have lead to us to assess the response of S. aureus to a reduced fluid shear environment. Culture in the RWV demonstrated that S. aureus grown under the low-shear condition had lower cell concentrations after 10 hours when compared to the control culture. Furthermore, the low-shear cultured bacteria displayed a reduction in carotenoid production, pigments responsible for their yellow/gold coloration. When exposed to various environmental stressors, post low-shear culture, a decrease in the ability to survive oxidative assault was observed compared to control cultures. The low fluid shear environment also resulted in a decrease in hemolysin secretion, a staphylococcal toxin responsible for red blood cell lysis. When challenged by the immune components present in human whole blood, low-shear cultured S. aureus demonstrated significantly reduced survival rates as compared to the control culture. Assays to determine the duration of these alterations

  12. Staphylococcus aureus Keratitis: A Review of Hospital Cases

    Science.gov (United States)

    Ong, Sherine Jue; Huang, Yhu-Chering; Tan, Hsin-Yuan; Ma, David H. K.; Lin, Hsin-Chiung; Yeh, Lung-Kun; Chen, Phil Y. F.; Chen, Hung-Chi; Chuang, Chih-Chun; Chang, Chee-Jen; Hsiao, Ching-Hsi

    2013-01-01

    Background Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important public health issue. The study aimed to characterize the patient demographics, clinical features, antibiotic susceptibility, and clinical outcomes of keratitis caused by S. aureus, and to make a comparison between MRSA and methicillin-sensitive S. aureus (MSSA) isolates. Methodology/Principal findings Patients (n = 59) with culture-proven S. aureus keratitis treated in Chang Gung Memorial Hospital between January 1, 2006, and December 31, 2010, were included in our study. Patients' demographic and clinical data were retrospectively reviewed. Twenty-six MRSA (44%) and 33 MSSA (56%) isolates were collected. The MRSA keratitis was significantly more common among the patients with healthcare exposure (P = 0.038), but 46.2% (12/26) of patients with MRSA keratitis were considered to have community-associated infections. All isolates were susceptible to vancomycin. MRSA isolates were significantly more resistant to clindamycin, erythromycin, and sulfamethoxazole/trimethoprim. Ocular surface disease was a significant risk factor for MRSA keratitis (P = 0.011). Visual outcome did not differ significantly between the MRSA and MSSA groups. However, age (B = 0.01, P = 0.035, 95% confidence interval [CI]: 0.001–0.019) and visual acuity at presentation (B = 0.749, Pkeratitis, especially for MRSA infections. Advanced age and poor visual acuity at presentation are important prognostic indicators for poor visual outcome in S. aureus keratitis. Oxacillin resistance may not be a significant prognostic indicator. PMID:24244625

  13. In vitro activity of ivermectin against Staphylococcus aureus clinical isolates

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    Shoaib Ashraf

    2018-02-01

    Full Text Available Abstract Background Ivermectin is an endectocide against many parasites. Though being a macrocyclic lactone, its activity against bacteria has been less known, possibly due to the fact that micromolar concentrations at tissue levels are required to achieve a therapeutic effect. Among pathogenic bacteria of major medical significance, Staphylococcus aureus cause a number of diseases in a wide variety of hosts including humans and animals. It has been attributed as one of the most pathogenic organisms. The emergence of methicillin resistance has made the treatment of S. aureus even more difficult as it is now resistant to most of the available antibiotics. Thus, search for alternate anti-staphylococcal agents requires immediate attention. Methods Twenty-one clinical isolates of S. aureus were isolated from bovine milk collected from Lahore and Faisalabad Pakistan. Different anthelmintics including levamisole, albendazole and ivermectin were tested against S. aureus to determine their minimum inhibitory concentrations. This was followed-up by growth curve analysis, spot assay and time-kill kinetics. Results The results showed that ivermectin but not levamisole or albendazole exhibited a potent anti-staphylococcal activity at the concentrations of 6.25 and 12.5 μg/ml against two isolates. Interestingly, one of the isolate was sensitive while the other was resistant to methicillin/cefoxitin. Conclusions Our novel findings indicate that ivermectin has an anti-bacterial effect against certain S. aureus isolates. However, to comprehend why ivermectin did not inhibit the growth of all Staphylococci needs further investigation. Nevertheless, we have extended the broad range of known pharmacological effects of ivermectin. As pharmacology and toxicology of ivermectin are well known, its further development as an anti-staphylococcal agent is potentially appealing.

  14. Characterization of a mouse-adapted Staphylococcus aureus strain.

    Directory of Open Access Journals (Sweden)

    Silva Holtfreter

    Full Text Available More effective antibiotics and a protective vaccine are desperately needed to combat the 'superbug' Staphylococcus aureus. While in vivo pathogenicity studies routinely involve infection of mice with human S. aureus isolates, recent genetic studies have demonstrated that S. aureus lineages are largely host-specific. The use of such animal-adapted S. aureus strains may therefore be a promising approach for developing more clinically relevant animal infection models. We have isolated a mouse-adapted S. aureus strain (JSNZ which caused a severe outbreak of preputial gland abscesses among male C57BL/6J mice. We aimed to extensively characterize this strain on a genomic level and determine its virulence potential in murine colonization and infection models. JSNZ belongs to the MLST type ST88, rare among human isolates, and lacks an hlb-converting phage encoding human-specific immune evasion factors. Naive mice were found to be more susceptible to nasal and gastrointestinal colonization with JSNZ than with the human-derived Newman strain. Furthermore, naïve mice required antibiotic pre-treatment to become colonized with Newman. In contrast, JSNZ was able to colonize mice in the absence of antibiotic treatment suggesting that this strain can compete with the natural flora for space and nutrients. In a renal abscess model, JSNZ caused more severe disease than Newman with greater weight loss and bacterial burden. In contrast to most other clinical isolates, JSNZ can also be readily genetically modified by phage transduction and electroporation. In conclusion, the mouse-adapted strain JSNZ may represent a valuable tool for studying aspects of mucosal colonization and for screening novel vaccines and therapies directed at preventing colonization.

  15. Heme Recognition By a Staphylococcus Aureus IsdE

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, J.C.; Vermeiren, C.L.; Heinrichs, D.E.; Murphy, M.E.P.

    2009-06-03

    Staphylococcus aureus is a Gram-positive bacterial pathogen and a leading cause of hospital acquired infections. Because the free iron concentration in the human body is too low to support growth, S. aureus must acquire iron from host sources. Heme iron is the most prevalent iron reservoir in the human body and a predominant source of iron for S. aureus. The iron-regulated surface determinant (Isd) system removes heme from host heme proteins and transfers it to IsdE, the cognate substrate-binding lipoprotein of an ATP-binding cassette transporter, for import and subsequent degradation. Herein, we report the crystal structure of the soluble portion of the IsdE lipoprotein in complex with heme. The structure reveals a bi-lobed topology formed by an N- and C-terminal domain bridged by a single {alpha}-helix. The structure places IsdE as a member of the helical backbone metal receptor superfamily. A six-coordinate heme molecule is bound in the groove established at the domain interface, and the heme iron is coordinated in a novel fashion for heme transporters by Met{sup 78} and His{sup 229}. Both heme propionate groups are secured by H-bonds to IsdE main chain and side chain groups. Of these residues, His{sup 299} is essential for IsdE-mediated heme uptake by S. aureus when growth on heme as a sole iron source is measured. Multiple sequence alignments of homologues from several other Gram-positive bacteria, including the human pathogens pyogenes, Bacillus anthracis, and Listeria monocytogenes, suggest that these other systems function equivalently to S. aureus IsdE with respect to heme binding and transport.

  16. Antibacterial mechanism of soybean isoflavone on Staphylococcus aureus.

    Science.gov (United States)

    Wang, Qian; Wang, Haitao; Xie, Mingjie

    2010-11-01

    Effects of different flavonoids on various bacterial strains have been extensively reported; however, the mechanism(s) of their action on bacterial cells remain largely elusive. In this study, the antibacterial mechanism of soybean isoflavone (SI) on Staphylococcus aureus is systematically investigated using 4'6-diamidino-2-phenylindole (DAPI) staining, pBR322DNA decatenation experiment mediated by topoisomerase and agarose gel electrophoresis for direct decatenation. The results of fluorescence microscopy and fluorescence spectrophotometer indicated that DAPI was integrated in Staphylococcus aureus. Additionally, the quantity of both DNA and RNA reduced to 66.47 and 60.18%, respectively, after treated with SI for 28 h. Effects of SI on topoisomerase I and II were also investigated. SI completely inhibited the pBR322DNA unwinding mediated by topoisomerase I and topoisomerase II at the concentration of 6.4 mg/ml and could denature the plasmid DNA at the concentration of 12.8 mg/ml. These results indicate that topoisomerase I and II are the most important targets by SI to restrain bacterial cell division.

  17. Bioactive Compounds Produced by Hypoxylon fragiforme against Staphylococcus aureus Biofilms

    Directory of Open Access Journals (Sweden)

    Kamila Tomoko Yuyama

    2017-12-01

    Full Text Available Treating infections organized in biofilms is a challenge due to the resistance of the pathogens against antibiotics and host immune cells. Many fungi grow in a wet environment, favorable for the growth of bacterial biofilms, and we speculated that fungi possess some strategies to control these bacterial biofilms. A fungus identified as Hypoxylon fragiforme, was collected in the Harz Mountains, Germany, and its mycelial culture was fermented in different culture media for 67 days to test its biological potential against bacterial biofilms. Sclerin, sclerin diacid and its 3-methyl monoester (methyl 1-(5-hydroxy-6-carboxylic-2,3,4-trimethylphenyl propionate are here described for the first time from this fungus. Sclerin and its diacid interfered with the biofilm formation of the pathogen Staphylococcus aureus, inhibiting 86% and 80% of the biofilm at 256 μg mL−1, respectively, but not killing the bacterium. Interestingly, the monomethylester of sclerin diacid was inactive. Although these compounds did not possess any activity against a pre-formed biofilm, they prevented its formation at subtoxic concentrations. Furthermore, sclerin and its diacid displayed a high specificity against Staphylococcus aureus, indicating a good strategy against pathogenic biofilms when combined with antibiotics.

  18. Pharmacotherapy for methicillin-resistant Staphylococcus aureus nosocomial pneumonia.

    Science.gov (United States)

    Segarra-Newnham, Marisel; Church, Timothy J

    2012-12-01

    To review the evidence for pharmacologic agents available in the treatment of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) pneumonia. A search of PubMed (1975-July 2012) was conducted using a combination of the terms methicillin-resistant Staphylococcus aureus, pneumonia, nosocomial, vancomycin, linezolid, telavancin, ceftaroline, tigecycline, and quinupristin/dalfopristin. Randomized comparative clinical trials, meta-analyses, and review articles published in English were included. A manual review of the bibliographies of available literature was conducted and all relevant information was included. Observational and in vitro studies were incorporated as indicated. Pharmacotherapy for the treatment of nosocomial MRSA pneumonia is limited. Vancomycin has been the treatment of choice for several years. Linezolid has demonstrated similar efficacy to vancomycin in randomized clinical trials and recent data have suggested that it may be superior in some cases, although there are limitations to this conclusion. Telavancin has also demonstrated similar clinical efficacy to vancomycin; however, the drug is not commercially available in the US. Other agents with MRSA activity include ceftaroline, clindamycin, quinupristin/dalfopristin, and tigecycline, although the evidence for their use in nosocomial pneumonia is limited. Based on the currently available evidence and cost-effectiveness, vancomycin should continue to be the drug of choice for most patients with nosocomial MRSA pneumonia. Linezolid is a reasonable alternative for patients with treatment failure while receiving vancomycin, isolates with vancomycin minimum inhibitory concentrations over 2 μg/mL, allergic reactions, or vancomycin-induced nephrotoxicity.

  19. Antimicrobial blue light inactivation of Methicillin-resistant Staphylococcus aureus

    Science.gov (United States)

    Wang, Yucheng; Dai, Tianhong; Gu, Ying

    2016-10-01

    Background: With the increasing emergence of multidrug-resistant (MDR) bacterial strains, there is a pressing need for the development of alternative treatment for infections. Antimicrobial blue light (aBL) has provided a simple and effective approach. Methods: We first investigated the effectiveness of aBL (415 nm) inactivation of USA300 LAClux (a communityacquired Methicillin-resistant Staphylococcus aureus strain) both in the planktonic and biofilm forms. The survival of the bacteria in suspensions was determined by serial dilution and that of the biofilm-embedded bacteria was determined by bioluminescence quantification. Using a mouse model of thermal burn infected with USA300 LAClux, we further assessed the effectiveness of aBL for treating localized infections. Bioluminescence imaging was performed to monitor in real time bacterial viability in vivo. Results: In vitro study showed that, for the planktonic counterpart of the bacteria or the 24-h-old biofilms, an irradiance of 55 mW/cm2 for 60 min resulted in a 4.61 log10 or 2.56 log10 inactivation, respectively. In vivo study using infected mouse burns demonstrated that a 2.56-log10 inactivation was achieved after 100-mW/cm2 irradiation for 62 min. Conclusions: aBL is a potential alternative approach for treating Methicillin-resistant Staphylococcus aureus infections.

  20. Methicillin-resistant staphylococcus aureus (MRSA) carriage in a dermatology unit

    Science.gov (United States)

    Pacheco, Renata L.; Lobo, Renata D.; Oliveira, Maura S.; Farina, Elthon F.; Santos, Cleide R.; Costa, Silvia F.; Padoveze, Maria Clara; Garcia, Cilmara P.; Trindade, Priscila A.; Quitério, Ligia M.; Rivitti, Evandro A.; Mamizuka, Elsa M.; Levin, Anna S.

    2011-01-01

    OBJECTIVE: The aim of this study was to characterize Staphylococcus aureus (MRSA) carriage in a dermatology unit. METHODS: This was a prospective and descriptive study. Over the course of 26 weeks, surveillance cultures were collected weekly from the anterior nares and skin of all patients hospitalized in a 20-bed dermatology unit of a tertiary-care hospital. Samples from healthcare workers (HCWS) were cultured at the beginning and end of the study. Colonized patients were put under contact precautions, and basic infection control measures were enforced. Staphylococcus aureus colonization pressure was determined monthly. Colonized and non-colonized patients were compared, and isolates were evaluated for antimicrobial susceptibility, SCCmec type, virulence factors, and type. RESULTS: Of the 142 patients evaluated, 64 (45%) were colonized by MRSA (39% hospital acquired; 25% community acquired; 36% indeterminate). Despite isolation precautions, hospital-acquired Staphylococcus aureus occurred in addition to the continuous entry of Staphylococcus aureus from the community. Colonization pressure increased from 13% to 59%, and pemphigus and other bullous diseases were associated with MRSA colonization. Eleven out of 71 HCWs (15%) were Staphylococcus aureus carriers, although only one worker carried a persistent clone. Of the hospital-acquired MRSA cases, 14/28 (50%) were SCCmec type IV (3 PFGE types), 13 were SCCmec type III (46%), and one had an indeterminate type. These types were also present among the community-acquired Staphylococcus aureus isolates. SSCmec type IV isolates were shown to be more susceptible than type III isolates. There were two cases of bloodstream infection, and the pvl and tst virulence genes were absent from all isolates. CONCLUSIONS: Dermatology patients were colonized by community- and hospital-acquired Staphylococcus aureus. Half of the nosocomial Staphylococcus aureus isolates were SCCmec type IV. Despite the identification of colonized

  1. Staphylococcus aureus entrance into the dairy chain: Tracking S. aureus from dairy cow to cheese

    Directory of Open Access Journals (Sweden)

    Judith Kümmel

    2016-10-01

    Full Text Available Staphylococcus aureus is one of the most important contagious mastitis pathogens in dairy cattle. Due to its zoonotic potential, control of S. aureus is not only of great economic importance in the dairy industry but also a significant public health concern. The aim of this study was to decipher the potential of bovine udder associated S. aureus as reservoir for S. aureus contamination in dairy production and processing. From 18 farms, delivering their milk to an alpine dairy plant for the production of smeared semi-hard and hard cheese. 1176 quarter milk (QM samples of all cows in lactation (n = 294 and representative samples form bulk tank milk (BTM of all farms were surveyed for coagulase positive (CPS and coagulase negative Staphylococci (CNS. Furthermore, samples from different steps of the cheese manufacturing process were tested for CPS and CNS. As revealed by chemometric-assisted FTIR spectroscopy and molecular subtyping (spa typing and multi locus sequence typing, dairy cattle represent indeed an important, yet underreported, entrance point of S. aureus into the dairy chain. Our data clearly show that certain S. aureus subtypes are present in primary production as well as in the cheese processing at the dairy plant. However, although a considerable diversity of S. aureus subtypes was observed in QM and BTM at the farms, only certain S. aureus subtypes were able to enter and persist in the cheese manufacturing at the dairy plant and could be isolated from cheese until day fourteen of ripening. Farm strains belonging to the FTIR cluster B1 and B3, which show genetic characteristics (t2953, ST8, enterotoxin profile: sea/sed/sej of the recently described S. aureus genotype B, most successfully contaminated the cheese production at the dairy plant. Thus our study fosters the hypothesis that genotype B S. aureus represent a specific challenge in control of S. aureus in the dairy chain that requires effective clearance strategies and hygienic

  2. Anti-alpha-hemolysin monoclonal antibodies mediate protection against Staphylococcus aureus pneumonia.

    Science.gov (United States)

    Ragle, Brook E; Bubeck Wardenburg, Juliane

    2009-07-01

    Staphylococcus aureus pneumonia is one of the most common invasive diseases caused by this human pathogen. S. aureus alpha-hemolysin, a pore-forming cytotoxin, is an essential virulence factor in the pathogenesis of pneumonia. Vaccine-based targeting of this toxin provides protection against lethal staphylococcal pneumonia in a murine model system, suggesting that a monoclonal antibody-based therapy may likewise prove to be efficacious for prevention and treatment of this disease. We report the generation of two distinct anti-alpha-hemolysin monoclonal antibodies that antagonize toxin activity, preventing human lung cell injury in vitro and protecting experimental animals against lethal S. aureus pneumonia. Each of these two monoclonal antibodies recognized an epitope within the first 50 amino acid residues of the mature toxin and blocked the formation of a stable alpha-hemolysin oligomer on the target cell surface. Active immunization with the first 50 amino acids of the toxin also conferred protection against S. aureus pneumonia. Together, these data reveal passive and active immunization strategies for prevention or therapy of staphylococcal pneumonia and highlight the potential role that a critical epitope may play in defining human susceptibility to this deadly disease.

  3. Staphylococcus aureus aggregation and coagulation mechanisms, and their function in host-pathogen interactions

    Science.gov (United States)

    Crosby, Heidi A.; Kwiecinski, Jakub; Horswill, Alexander R.

    2017-01-01

    The human commensal bacterium Staphylococcus aureus can cause a wide range of infections ranging from skin and soft tissue infections to invasive diseases like septicemia, endocarditis, and pneumonia. Muticellular organization almost certainly contributes to S. aureus pathogenesis mechanisms. While there has been considerable focus on biofilm formation and its role in colonizing prosthetic joints and indwelling devices, less attention has been paid to non-surface attached group behavior like aggregation and clumping. S. aureus is unique in its ability to coagulate blood, and it also produces multiple fibrinogen-binding proteins that facilitate clumping. Formation of clumps, which are large, tightly-packed groups of cells held together by fibrin(ogen), has been demonstrated to be important for S. aureus virulence and immune evasion. Clumps of cells are able to avoid detection by the host’s immune system due to a fibrin(ogen) coat that acts as a shield, and the size of the clumps facilitates evasion of phagocytosis. In addition, clumping could be an important early step in establishing infections that involve tight clusters of cells embedded in host matrix proteins, such as soft tissue abscesses and endocarditis. In this review we discuss clumping mechanisms and regulation, as well as what is known about how clumping contributes to immune evasion. PMID:27565579

  4. Investigation of biofilm formation in clinical isolates of Staphylococcus aureus.

    Science.gov (United States)

    Cassat, James E; Lee, Chia Y; Smeltzer, Mark S

    2007-01-01

    As with many other bacterial species, the most commonly used method to assess staphylococcal biofilm formation in vitro is the microtiter plate assay. This assay is particularly useful for comparison of multiple strains including large-scale screens of mutant libraries. When such screens are applied to the coagulase-negative staphylococci in general, and Staphylococcus epidermidis in particular, they are relatively straightforward by comparison with microtiter plate assays used to assess biofilm formation in other bacterial species. However, in the case of clinical isolates of Staphylococcus aureus, including methicillin-resistant S. aureus, we have found it necessary to employ specific modifications including precoating of the wells of the microtiter plate with plasma proteins and supplementation of the medium with both salt and glucose. In this chapter, we describe the microtiter plate assay in the specific context of clinical isolates of S. aureus and the use of these modifications. A second in vitro method, which also is generally dependent on coating with plasma proteins and supplementation of the growth medium, is the use of flow cells. In this method, bacteria are allowed to attach to a surface and then monitored with respect to their ability to remain attached to the substrate and differentiate into mature biofilms under the constant pressure of fluid shear force. Although flow cells are not applicable to large-scale screens, we have found that they provide a more reproducible and accurate assessment of the capacity of S. aureus clinical isolates to form a biofilm. They also provide a means of analyzing structural differences in biofilm architecture and isolating bacteria and/or spent media for analysis of physiological and metabolic changes associated with the adaptive response to growth in a biofilm. While a primary focus of this chapter is on the use of in vitro assays to assess biofilm formation in clinical isolates of S. aureus, it is important to

  5. Individual predisposition to Staphylococcus aureus colonization in pigs based on quantification, carriage dynamics and serological profiles

    DEFF Research Database (Denmark)

    Gongora, Carmen Espinosa; Dahl, Jan; Elvstrøm, Anders

    2015-01-01

    Previous research on Staphylococcus aureus in pigs focused on livestock-associated methicillin-resistant S. aureus (MRSA) and had qualitative cross-sectional design. This study aimed to elucidate frequency, load and stability of S. aureus nasal carriage in pigs over time and investigated possible...

  6. Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium

    NARCIS (Netherlands)

    Tulinski, P.; Duim, B.; Wittink, F.R.; Jonker, M.J.; Breit, T.M.; van Putten, J.P.; Wagenaar, J.A.; Fluit, A.C.

    2014-01-01

    Background: Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig

  7. Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium

    NARCIS (Netherlands)

    Tulinski, P.; Duim, B.; Wittink, F.R.; Jonker, M.J.; Breit, T.M.; Van Putten, J.P.; Wagenaar, J.A.; Fluit, A.C.

    2014-01-01

    Background Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig

  8. Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium

    NARCIS (Netherlands)

    Tulinski, Pawel; Duim, Birgitta; Wittink, Floyd R; Jonker, Martijs J; Breit, Timo M; van Putten, Jos P; Wagenaar, Jaap A; Fluit, Ad C

    2014-01-01

    BACKGROUND: Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig

  9. Long-term cortisol levels are not associated with nasal carriage of Staphylococcus aureus

    NARCIS (Netherlands)

    L. Manenschijn (Laura); A.M. Jetten; W.J.B. van Wamel (Willem); M. Tavakol (Mehri); E.L.T. van den Akker (Erica); J.W. Koper (Jan); A.F. van Belkum (Alex); E.F.C. van Rossum (Liesbeth)

    2012-01-01

    textabstractStaphylococcus aureus (S. aureus) colonizes the anterior nares in part of the population and the persistent carrier state is associated with increased infection risk. Knowledge concerning the determinants of S. aureus nasal carriage is limited. Previously, we found that glucocorticoid

  10. Staphylococcus aureus nasopharyngeal carriage in rural and urban northern Vietnam.

    Science.gov (United States)

    Van Nguyen, Kinh; Zhang, Tianying; Thi Vu, Bich Ngoc; Dao, Trinh Tuyet; Tran, Toan Khanh; Thi Nguyen, Diep Ngoc; Thi Tran, Huong Kieu; Thi Nguyen, Chuc Kim; Fox, Annette; Horby, Peter; Wertheim, Heiman

    2014-12-01

    Staphylococcus aureus is a common human pathogen that can colonise the respiratory tract and cause infection. Here we investigate the risk factors associated with nasopharyngeal carriage of S. aureus (including methicillin-resistant S. aureus [MRSA]) in Vietnam. Between February and June 2012, nasal and pharyngeal swabs for S. aureus culture, and demographic and socioeconomic data were taken from 1016 participants in urban and rural northern Vietnam, who were randomly selected from pre-specified age strata. Overall S. aureus prevalence was 303/1016 (29.8%; adjusted for age: 33.8%). Carriage in the main cohort was found to be associated with younger age (≤5 years [OR 3.13, CI 1.62-6.03]; 6-12 [OR 6.87, CI 3.95-11.94]; 13-19 [OR 6.47, CI 3.56-11.74]; 20-29 [OR 4.73, CI 2.40-9.31]; 30-59 [OR 1.74, CI 1.04-2.92); with ≥60 as reference), living in an urban area (OR 1.36, CI 1.01-1.83) and antibiotics use (OR 0.69, CI 0.49-0.96). MRSA was detected in 80/1016 (7.9%). Being aged ≤5 years (OR 4.84, CI 1.47-15.97); 6-12 (OR 10.21, CI 3.54-29.50); 20-29 (OR 4.01, CI 1.09-14.77) and wealth (>3/5 wealth index, OR 1.63 CI 1.01-2.62) were significant risk factors for MRSA carriage. Nasopharyngeal carriage of S. aureus is present in one-third of the Vietnamese population, and is more prevalent among children. Pharyngeal carriage is more common than nasal carriage. Risk factors for S. aureus (including MRSA) carriage are identified in the community. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

  11. Persister formation in Staphylococcus aureus is associated with ATP depletion

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, Brian P.; Rowe, Sarah E.; Gandt, Autumn Brown; Nuxoll, Austin S.; Donegan, Niles P.; Zalis, Eliza A.; Clair, Geremy; Adkins, Joshua N.; Cheung, Ambrose L.; Lewis, Kim

    2016-04-18

    Persisters are dormant phenotypic variants of bacterial cells that are tolerant to killing by antibiotics1. Persisters are associated with chronic bacterial infection and antibiotic treatment failure. In Escherichia coli, toxin/antitoxin (TA) modules are responsible for persister formation. The mechanism of persister formation in Gram positive bacteria is unknown. Staphylococcus aureus is a major human pathogen, responsible for a variety of chronic and relapsing infections such as osteomyelitis, endocarditis and infections of implanted devices. Deleting TA modules in S. aureus did not affect the level of persisters. Here we show that S. aureus persisters are produced due to a stochastic entrance to stationary phase accompanied by a drop in intracellular ATP. Cells expressing stationary state markers are present throughout the growth phase, increasing in frequency with cell density. Cell sorting revealed that expression of stationary markers was associated with a 100-1000 fold increased likelihood of survival to antibiotic challenge. We find that the antibiotic tolerance of these cells is due to a drop in intracellular ATP. The ATP level of the cell is predictive of bactericidal antibiotic efficacy and explains bacterial tolerance to antibiotic treatment.

  12. Severe Rhabdomyolysis Associated with Staphylococcus aureus Acute Endocarditis Requiring Surgery.

    Science.gov (United States)

    Ravry, Céline; Fedou, Anne-Laure; Dubos, Maria; Denes, Éric; Etchecopar, Caroline; Barraud, Olivier; Vignon, Philippe; François, Bruno

    2015-12-01

    Rhabdomyolysis has multiple etiologies with unclear mechanisms; however, rhabdomyolysis caused by Staphylococcus aureus infection is rare. A case report of severe rhabdomyolysis in a patient who presented with endocarditis caused by methicillin-susceptible S. aureus and review of relevant literature. The patient had a history of cardiac surgery for tetralogy of Fallot. He was admitted to the hospital because of fever and digestive symptoms. Respiratory and hemodynamic status deteriorated rapidly, leading to admission to the intensive care unit (ICU) for mechanical ventilation and vasopressor support. Laboratory tests disclosed severe rhabdomyolysis with a serum concentration of creatine kinase that peaked at 49,068 IU/L; all blood cultures grew methicillin-susceptible S. aureus. Antibiotic therapy was amoxicillin-clavulanic acid, ciprofloxacin, and gentamicin initially and was changed subsequently to oxacillin, clindamycin, and gentamicin. Transesophageal echocardiography showed vegetation on the pulmonary valve, thus confirming the diagnosis of acute endocarditis. Viral testing and computed tomography (CT) scan ruled out any obvious alternative etiology for rhabdomyolysis. Bacterial analysis did not reveal any specificity of the staphylococcal strain. The patient improved with antibiotics and was discharged from the ICU on day 26. He underwent redux surgery for valve replacement on day 53. Staphylococcal endocarditis should be suspected in cases of severe unexplained rhabdomyolysis with acute infectious symptoms.

  13. Chalcone AttenuatesStaphylococcus aureusVirulence by Targeting Sortase A and Alpha-Hemolysin.

    Science.gov (United States)

    Zhang, Bing; Teng, Zihao; Li, Xianhe; Lu, Gejin; Deng, Xuming; Niu, Xiaodi; Wang, Jianfeng

    2017-01-01

    Staphylococcus aureus ( S .aureus) resistance, considered a dilemma for the clinical treatment of this bacterial infection, is becoming increasingly intractable. Novel anti-virulence strategies will undoubtedly provide a path forward in combating these resistant bacterial infections. Sortase A (SrtA), an enzyme responsible for anchoring virulence-related surface proteins, and alpha-hemolysin (Hla), a pore-forming cytotoxin, have aroused great scientific interest, as they have been regarded as targets for promising agents against S. aureus infection. In this study, we discovered that chalcone, a natural small compound with little anti- S. aureus activity, could significantly inhibit SrtA activity with an IC 50 of 53.15 μM and Hla hemolysis activity with an IC 50 of 17.63 μM using a fluorescence resonance energy transfer (FRET) assay and a hemolysis assay, respectively. In addition, chalcone was proven to reduce protein A (SpA) display in intact bacteria, binding to fibronectin, formation of biofilm and S. aureus invasion. Chalcone could down-regulate the transcriptional levels of the hla gene and the agrA gene, thus leading to a reduction in the expression of Hla and significant protection against Hla-mediated A549 cell injury; more importantly, chalcone could also reduce mortality in infected mice. Additionally, molecular dynamics simulations and mutagenesis assays were used to identify the mechanism of chalcone against SrtA, which implied that the inhibitory activity lies in the bond between chalcone and SrtA residues Val168, Ile182, and Arg197. Taken together, the in vivo and in vitro experiments suggest that chalcone is a potential novel therapeutic compound for S. aureus infection via targeting SrtA and Hla.

  14. Staphylococcus aureus Colonization: Modulation of Host Immune Response and Impact on Human Vaccine Design

    Science.gov (United States)

    Brown, Aisling F.; Leech, John M.; Rogers, Thomas R.; McLoughlin, Rachel M.

    2014-01-01

    In apparent contrast to its invasive potential Staphylococcus aureus colonizes the anterior nares of 20–80% of the human population. The relationship between host and microbe appears particularly individualized and colonization status seems somehow predetermined. After decolonization, persistent carriers often become re-colonized with their prior S. aureus strain, whereas non-carriers resist experimental colonization. Efforts to identify factors facilitating colonization have thus far largely focused on the microorganism rather than on the human host. The host responds to S. aureus nasal colonization via local expression of anti-microbial peptides, lipids, and cytokines. Interplay with the co-existing microbiota also influences colonization and immune regulation. Transient or persistent S. aureus colonization induces specific systemic immune responses. Humoral responses are the most studied of these and little is known of cellular responses induced by colonization. Intriguingly, colonized patients who develop bacteremia may have a lower S. aureus-attributable mortality than their non-colonized counterparts. This could imply a staphylococcal-specific immune “priming” or immunomodulation occurring as a consequence of colonization and impacting on the outcome of infection. This has yet to be fully explored. An effective vaccine remains elusive. Anti-S. aureus vaccine strategies may need to drive both humoral and cellular immune responses to confer efficient protection. Understanding the influence of colonization on adaptive response is essential to intelligent vaccine design, and may determine the efficacy of vaccine-mediated immunity. Clinical trials should consider colonization status and the resulting impact of this on individual patient responses. We urgently need an increased appreciation of colonization and its modulation of host immunity. PMID:24409186

  15. Chalcone Attenuates Staphylococcus aureus Virulence by Targeting Sortase A and Alpha-Hemolysin

    Directory of Open Access Journals (Sweden)

    Bing Zhang

    2017-09-01

    Full Text Available Staphylococcus aureus (S.aureus resistance, considered a dilemma for the clinical treatment of this bacterial infection, is becoming increasingly intractable. Novel anti-virulence strategies will undoubtedly provide a path forward in combating these resistant bacterial infections. Sortase A (SrtA, an enzyme responsible for anchoring virulence-related surface proteins, and alpha-hemolysin (Hla, a pore-forming cytotoxin, have aroused great scientific interest, as they have been regarded as targets for promising agents against S. aureus infection. In this study, we discovered that chalcone, a natural small compound with little anti-S. aureus activity, could significantly inhibit SrtA activity with an IC50 of 53.15 μM and Hla hemolysis activity with an IC50 of 17.63 μM using a fluorescence resonance energy transfer (FRET assay and a hemolysis assay, respectively. In addition, chalcone was proven to reduce protein A (SpA display in intact bacteria, binding to fibronectin, formation of biofilm and S. aureus invasion. Chalcone could down-regulate the transcriptional levels of the hla gene and the agrA gene, thus leading to a reduction in the expression of Hla and significant protection against Hla-mediated A549 cell injury; more importantly, chalcone could also reduce mortality in infected mice. Additionally, molecular dynamics simulations and mutagenesis assays were used to identify the mechanism of chalcone against SrtA, which implied that the inhibitory activity lies in the bond between chalcone and SrtA residues Val168, Ile182, and Arg197. Taken together, the in vivo and in vitro experiments suggest that chalcone is a potential novel therapeutic compound for S. aureus infection via targeting SrtA and Hla.

  16. In Vitro Antibacterial Activity of Unconjugated and Conjugated Bile Salts on Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Thippeswamy H. Sannasiddappa

    2017-08-01

    Full Text Available Bile salts are potent antimicrobial agents and are an important component of innate defenses in the intestine, giving protection against invasive organisms. They play an important role in determining microbial ecology of the intestine and alterations in their levels can lead to increased colonization by pathogens. We have previously demonstrated survival of the opportunistic pathogen Staphylococcus aureus in the human colonic model. Thus investigating the interaction between S. aureus and bile salts is an important factor in understanding its ability to colonize in the host intestine. Harnessing bile salts may also give a new avenue to explore in the development of therapeutic strategies to control drug resistant bacteria. Despite this importance, the antibacterial activity of bile salts on S. aureus is poorly understood. In this study, we investigated the antibacterial effects of the major unconjugated and conjugated bile salts on S. aureus. Several concentration-dependent antibacterial mechanisms were found. Unconjugated bile salts at their minimum inhibitory concentration (cholic and deoxycholic acid at 20 and 1 mM, respectively killed S. aureus, and this was associated with increased membrane disruption and leakage of cellular contents. Unconjugated bile salts (cholic and deoxycholic acid at 8 and 0.4 mM, respectively and conjugated bile salts (glycocholic and taurocholic acid at 20 mM at their sub inhibitory concentrations were still able to inhibit growth through disruption of the proton motive force and increased membrane permeability. We also demonstrated that unconjugated bile salts possess more potent antibacterial action on S. aureus than conjugated bile salts.

  17. Absence of patient-to-patient intrahospital transmission of Staphylococcus aureus as determined by whole-genome sequencing.

    Science.gov (United States)

    Long, S Wesley; Beres, Stephen B; Olsen, Randall J; Musser, James M

    2014-10-07

    Nosocomial transmission of pathogens is a major health care challenge. The increasing spread of antibiotic-resistant strains represents an ongoing threat to public health. Previous Staphylococcus aureus transmission studies have focused on transmission of S. aureus between asymptomatic carriers or used low-resolution typing methods such as multilocus sequence typing (MLST) or spa typing. To identify patient-to-patient intrahospital transmission using high-resolution genetic analysis, we sequenced the genomes of a consecutive set of 398 S. aureus isolates from sterile-site infections. The S. aureus strains were collected from four hospitals in the Houston Methodist Hospital System over a 6-month period. Importantly, we discovered no evidence of transmission of S. aureus between patients with sterile-site infections. The lack of intrahospital transmission may reflect a fundamental difference between day-to-day transmission events in the hospital setting and the more frequently studied outbreak scenarios. Importance: Previous studies have suggested that nosocomial transmission of S. aureus is common. Our data revealed an unexpected lack of evidence for intrahospital transmission of S. aureus between patients with invasive infections. This finding has important implications for hospital infection control and public health efforts. In addition, our data demonstrate that highly related pools of S. aureus strains exist in the community which may complicate outbreak investigations. Copyright © 2014 Long et al.

  18. The molecular changing mechanism of Ampicillin-Sulbactam resistant Staphylococcus aureus towards Methicillin resistant Staphylococcus aureus

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    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.

  19. [Genotyping and drug resistance of methicillin-resistant Staphylococcus aureus].

    Science.gov (United States)

    Yao, Ming; Guan, Lifeng; Jia, Wei; Wang, Linlin; Li, Gang; Wu, Xuejun; Sun, Tao

    2014-10-01

    To investigate the genotype of staphylococcal chromosomal cassette mec (SCCmec) in methicillin-resistant Staphylococcus aureus (MRSA) isolated from burn wards and its current status of drug resistance. One hundred and seventy-nine strains of Staphylococcus aureus were isolated from wound excretion, blood, and sputum samples of patients that were admitted to ICU or public wards of our Department of Burns and Plastic Surgery from September 2012 to September 2013. Among them, 68 strains were from ICU and 111 strains from public wards. The MRSA phenotype of Staphylococcus aureus was detected with cefoxitin K-B disk diffusion method, and the isolation rates of MRSA in ICU and public wards were compared. Genotyping of SCCmec was performed by PCR in strains of MRSA. In the meantime, the identification result of MRSA by K-B method was verified through detecting methicillin-resistant determinant mecA. The antimicrobial resistance of MRSA and methicillin-sensitive Staphylococcus aureus (MSSA) to 23 kinds of commonly used antibiotics in clinic were detected by K-B disk diffusion method. Except for the antibiotics to which the resistant rates of MRSA were 100.0% or 0, the resistant rates of SCCmecIII MRSA and non-SCCmec III MRSA to the rest of antibiotics were compared. Data were processed with Pearson chi-square test or corrected chi-square test. One hundred and forty-eight strains out of the 179 Staphylococcus aureus were identified as MRSA (accounting for 82.7%), among which 62 were originated from ICU and 86 from public wards. The rest 31 strains of Staphylococcus aureus were MSSA, accounting for 17.3%. The percentage of MRSA in the isolated Staphylococcus aureus was 91.2% (62/68) in ICU, which was significantly higher than that in the public wards [77.5% (86/111), χ2 = 5.526, P = 0.019]. PCR detection showed that the 148 strains of MRSA harbored the mecA gene, out of which 106 strains were SCCmec III positive, accounting for 71.6%. The percentages of SCCmec III type MRSA

  20. Novel rat tail discitis model using bioluminescent Staphylococcus aureus.

    Science.gov (United States)

    Bostian, Phillip A; Karnes, Jonathan M; Cui, Shari; Robinson, Lisa J; Daffner, Scott D; Witt, Michelle R; Emery, Sanford E

    2017-09-01

    Management of spondylodiscitis is a challenging clinical problem requiring medical and surgical treatment strategies. The purpose of this study was to establish a rat model of spondylodiscitis that utilizes bioluminescent Staphylococcus aureus (S. aureus), thus permitting in vivo surveillance of infection intensity. Inocula of the bioluminescent S. aureus strain XEN36 were created in concentrations of 10 2 CFU/0.1 ml, 10 4  CFU/0.1 ml, and 10 6  CFU/0.1 ml. Three groups of rats were injected with the bacteria in the most proximal intervertebral tail segment. The third most proximal tail segment was injected with saline as a control. Bioluminescence was measured at baseline, 3 days, and weekly for a total of 6 weeks. Detected bioluminescence for each group peaked at day 3 and returned to baseline in 21 days. The average intensity was highest for the experimental group injected with the most concentrated bacterial solution (10 6  CFU/0.1 ml). Radiographic analysis revealed loss of intervertebral disc space and evidence of osseous bridging. Saline-injected spaces exhibited no decrease in intervertebral spacing as compared to distal sites. Histologic analysis revealed neutrophilic infiltrates, destruction of the annulus fibrosus and nucleus pulposus, destruction of vertebral endplates, and osseous bridging. Saline-injected discs exhibited preserved annulus fibrosus and nucleus pulposus on histology. This study demonstrates that injection of bioluminescent S. aureus into the intervertebral disc of a rat tail is a viable animal model for spondylodiscitis research. This model allows for real-time, in vivo quantification of infection intensity, which may decrease the number of animals required for infection studies of the intervertebral disc. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2075-2081, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  1. Applying Convergent Immunity to Innovative Vaccines Targeting Staphylococcus aureus

    Science.gov (United States)

    Yeaman, Michael R.; Filler, Scott G.; Schmidt, Clint S.; Ibrahim, Ashraf S.; Edwards, John E.; Hennessey, John P.

    2014-01-01

    Recent perspectives forecast a new paradigm for future “third generation” vaccines based on commonalities found in diverse pathogens or convergent immune defenses to such pathogens. For Staphylococcus aureus, recurring infections and a limited success of vaccines containing S. aureus antigens imply that native antigens induce immune responses insufficient for optimal efficacy. These perspectives exemplify the need to apply novel vaccine strategies to high-priority pathogens. One such approach can be termed convergent immunity, where antigens from non-target organisms that contain epitope homologs found in the target organism are applied in vaccines. This approach aims to evoke atypical immune defenses via synergistic processes that (1) afford protective efficacy; (2) target an epitope from one organism that contributes to protective immunity against another; (3) cross-protect against multiple pathogens occupying a common anatomic or immunological niche; and/or (4) overcome immune subversion or avoidance strategies of target pathogens. Thus, convergent immunity has a potential to promote protective efficacy not usually elicited by native antigens from a target pathogen. Variations of this concept have been mainstays in the history of viral and bacterial vaccine development. A more far-reaching example is the pre-clinical evidence that specific fungal antigens can induce cross-kingdom protection against bacterial pathogens. This trans-kingdom protection has been demonstrated in pre-clinical studies of the recombinant Candida albicans agglutinin-like sequence 3 protein (rAls3) where it was shown that a vaccine containing rAls3 provides homologous protection against C. albicans, heterologous protection against several other Candida species, and convergent protection against several strains of S. aureus. Convergent immunity reflects an intriguing new approach to designing and developing vaccine antigens and is considered here in the context of vaccines to target S

  2. Applying Convergent Immunity to Innovative Vaccines Targeting Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michael R Yeaman

    2014-09-01

    Full Text Available Recent perspectives forecast a new paradigm for future 3rd generation vaccines based on commonalities found in diverse pathogens or convergent immune defenses to such pathogens. For Staphylococcus aureus, recurring infections and a limited success of vaccines containing S. aureus antigens imply that native antigens induce immune responses insufficient for optimal efficacy. These perspectives exemplify the need to apply novel vaccine strategies to high priority pathogens. One such approach can be termed convergent immunity, where antigens from non-target organisms that contain epitope homologues found in the target organism are applied in vaccines. This approach aims to evoke atypical immune defenses via synergistic processes that 1 afford protective efficacy; 2 target an epitope from one organism that contributes to protective immunity against another; 3 cross-protect against multiple pathogens occupying a common anatomic or immunologic niche; and/or 4 overcome immune subversion or avoidance strategies of target pathogens. Thus, convergent immunity has a potential to promote protective efficacy not usually elicited by native antigens from a target pathogen. Variations of this concept have been mainstays in the history of viral and bacterial vaccine development. A more far-reaching example is the pre–clinical evidence that specific fungal antigens can induce cross-kingdom protection against bacterial pathogens. This trans-kingdom protection has been demonstrated in preclinical studies of the recombinant Candida albicans agglutinin-like sequence 3 protein (rAls3 where it was shown that a vaccine containing rAls3 provides homologous protection against C. albicans, heterologous protection against several other Candida species, and convergent protection against several strains of S. aureus. Convergent immunity reflects an intriguing new approach to designing and developing vaccine antigens and is considered here in the context of vaccines to target

  3. Applying Convergent Immunity to Innovative Vaccines Targeting Staphylococcus aureus.

    Science.gov (United States)

    Yeaman, Michael R; Filler, Scott G; Schmidt, Clint S; Ibrahim, Ashraf S; Edwards, John E; Hennessey, John P

    2014-01-01

    Recent perspectives forecast a new paradigm for future "third generation" vaccines based on commonalities found in diverse pathogens or convergent immune defenses to such pathogens. For Staphylococcus aureus, recurring infections and a limited success of vaccines containing S. aureus antigens imply that native antigens induce immune responses insufficient for optimal efficacy. These perspectives exemplify the need to apply novel vaccine strategies to high-priority pathogens. One such approach can be termed convergent immunity, where antigens from non-target organisms that contain epitope homologs found in the target organism are applied in vaccines. This approach aims to evoke atypical immune defenses via synergistic processes that (1) afford protective efficacy; (2) target an epitope from one organism that contributes to protective immunity against another; (3) cross-protect against multiple pathogens occupying a common anatomic or immunological niche; and/or (4) overcome immune subversion or avoidance strategies of target pathogens. Thus, convergent immunity has a potential to promote protective efficacy not usually elicited by native antigens from a target pathogen. Variations of this concept have been mainstays in the history of viral and bacterial vaccine development. A more far-reaching example is the pre-clinical evidence that specific fungal antigens can induce cross-kingdom protection against bacterial pathogens. This trans-kingdom protection has been demonstrated in pre-clinical studies of the recombinant Candida albicans agglutinin-like sequence 3 protein (rAls3) where it was shown that a vaccine containing rAls3 provides homologous protection against C. albicans, heterologous protection against several other Candida species, and convergent protection against several strains of S. aureus. Convergent immunity reflects an intriguing new approach to designing and developing vaccine antigens and is considered here in the context of vaccines to target S

  4. Methicillin resistant Staphylococcus aureus (MRSA in India: Prevalence & susceptibility pattern

    Directory of Open Access Journals (Sweden)

    Indian Network for Surveillance of Antimicrobial Resistance (INSAR group, India

    2013-01-01

    Full Text Available Background & objectives: Methicillin resistant Staphylococcus aureus (MRSA is endemic in India and is a dangerous pathogen for hospital acquired infections. This study was conducted in 15 Indian tertiary care centres during a two year period from January 2008 to December 2009 to determine the prevalence of MRSA and susceptibility pattern of S. aureus isolates in India. Methods: All S. aureus isolates obtained during the study period in the participating centres were included in the study. Each centre compiled their data in a predefined template which included data of the antimicrobial susceptibility pattern, location of the patient and specimen type. The data in the submitted templates were collated and analysed. Results: A total of 26310 isolates were included in the study. The overall prevalence of methicillin resistance during the study period was 41 per cent. Isolation rates for MRSA from outpatients, ward inpatients and ICU were 28, 42 and 43 per cent, respectively in 2008 and 27, 49 and 47 per cent, respectively in 2009. The majority of S. aureus isolates was obtained from patients with skin and soft tissue infections followed by those suffering from blood stream infections and respiratory infections. Susceptibility to ciprofloxacin was low in both MSSA (53% and MRSA (21%. MSSA isolates showed a higher susceptibility to gentamicin, co-trimoxazole, erythromycin and clindamycin as compared to MRSA isolates. No isolate was found resistant to vancomycin or linezolid. Interpretation & conclusions: The study showed a high level of MRSA in our country. There is a need to study epidemiology of such infections. Robust antimicrobial stewardship and strengthened infection control measures are required to prevent spread and reduce emergence of resistance.

  5. Antibiotic resistance and molecular epidemiology of Staphylococcus aureus in Nigeria

    Directory of Open Access Journals (Sweden)

    Oyedara Omotayo

    2011-05-01

    Full Text Available Abstract Background Staphylococcus aureus is an important pathogen causing a wide range of infections in the hospital and community setting. In order to have adequate information for treatment of S. aureus infections, it is crucial to understand the trends in the antibiotic-resistance patterns. In addition, the occurrence and changes in types of S. aureus, clonal identities, and their geographic spread is essential for the establishment of adequate infection control programmes. In this study, 68 S. aureus isolates obtained from clinical and non-clinical sources in Nigeria between January and April 2009 were characterized using phenotypic and molecular methods. Results All the S. aureus isolates were susceptible to teicoplanin, vancomycin, phosphomycin, fusidic acid, rifampicin, daptomycin, mupirocin, linezolid and tigecycline. Sixteen percent of the isolates were resistant to oxacillin, while 55% and 72% of isolates were resistant to tetracycline and trimethoprim/sulphamethoxazole (cotrimoxazole, respectively (Table 1. There was excellent correlation between the broth microdilution assay and detection of antibiotic resistance genes by the multiplex PCR, in the determination of S. aureus resistance to erythromycin, gentamicin, methicillin and tetracycline. A total of 28 spa types were identified in the study, and the predominant spa type among the methicillin-susceptible S. aureus (MSSA isolates was t084 (13 isolates. The t037-ST241-SCCmecIII type was the only clone identified in Maiduguri (North-East Nigeria while in South-West Nigeria, diversity among the MRSA isolates (t451-ST8-SCCmecV; t008-ST94-SCCmecIV; t002-ST5-SCCmecV; t064-ST8-SCCmecV was observed. The toxin genes seh and etd were detected in isolates affiliated with clonal complexes CC1, CC80 and sequence type ST25, respectively. The proportion of PVL-positive isolates among MSSA was high (40%. Most of the PVL-positive MSSA isolates were obtained from wound infections and associated

  6. Shedding of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus from adult and pediatric bathers in marine waters

    Directory of Open Access Journals (Sweden)

    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

  7. Escherichia coli and Staphylococcus aureus : bad news and good news from the European Antimicrobial Resistance Surveillance Network (EARS-Net, formerly EARSS), 2002 to 2009

    NARCIS (Netherlands)

    Gagliotti, C.; Balode, A.; Baquero, F.; Degener, J.; Grundmann, H.; Gur, D.; Jarlier, V.; Kahlmeter, G.; Monen, J.; Monnet, D. L.; Rossolini, G. M.; Suetens, C.; Weist, K.; Heuer, O.

    2011-01-01

    Based on data collected by the European Antimicrobial Resistance Surveillance Network (EARS-Net) and the former EARSS, the present study describes the trends in antimicrobial susceptibility patterns and occurrence of invasive infections caused by Escherichia coli and Staphylococcus aureus in the

  8. Staphylococcus epidermidis ΔSortase A strain elicits protective immunity against Staphylococcus aureus infection.

    Science.gov (United States)

    Tan, Chao; Wang, Jun; Hu, Yifang; Wang, Peng; Zou, Lili

    2017-01-01

    Staphylococcus aureus and Staphylococcus epidermidis are two of the most significant opportunistic human pathogens, causing medical implant and nosocomial infections worldwide. These bacteria contain surface proteins that play crucial roles in multiple biological processes. It has become apparent that they have evolved a number of unique mechanisms by which they can immobilise proteins on their surface. Notably, a conserved cell membrane-anchored enzyme, sortase A (SrtA), can catalyse the covalent attachment of precursor bacterial cell wall-attached proteins to peptidoglycan. Considering its indispensable role in anchoring substrates to the cell wall and its effects on virulence, SrtA has attracted great attention. In this study, a 549-bp gene was cloned from a pathogenic S. epidermidis strain, YC-1, which shared high identity with srtA from other Staphylococcus spp. A mutant strain, YC-1ΔsrtA, was then constructed by allelic exchange mutagenesis. The direct survival rate assay suggested that YC-1ΔsrtA had a lower survival capacity in healthy mice blood compare with the wild-type strain, indicating that the deletion of srtA affects the virulence and infectious capacity of S. epidermidis YC-1. YC-1ΔsrtA was then administered via intraperitoneal injection and it provided a relative percent survival value of 72.7 % in mice against S. aureus TC-1 challenge. These findings demonstrate the possbility that YC-1ΔsrtA might be used as a live attenuated vaccine to produce cross-protection against S. aureus.

  9. Severe Staphylococcus aureus Endocarditis Presenting as Peripartum Thrombotic Thrombocytopenic Purpura.

    Science.gov (United States)

    Quinn, Kieran L; Osmond, Mark; Badiwala, Mitesh; Sermer, Mathew; Lapinsky, Stephen E

    2016-11-01

    Thrombotic thrombocytopenic purpura (TTP) is a life-threatening illness that occurs in both pregnant and non-pregnant women. Several other conditions can mimic the disease, which makes the diagnosis challenging. We describe a case of severe Staphylococcus aureus endocarditis that initially presented as peripartum TTP in a 39-year-old woman at 29+6 weeks' gestation. We give an overview of the diagnostic considerations and management of thrombocytopenia in pregnancy and review the literature related to TTP and peripartum infective endocarditis. Given the significant differences in definitive therapies for the spectrum of thrombocytopenic conditions that occur in pregnancy, timely and accurate diagnosis of TTP is critical for optimal management. Copyright © 2016 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.

  10. Pancreatic Abscess in a cat due to Staphylococcus aureus infection.

    Science.gov (United States)

    Nemoto, Yuki; Haraguchi, Tomoya; Shimokawa Miyama, Takako; Kobayashi, Kosuke; Hama, Kaori; Kurogouchi, Yosuke; Fujiki, Noriyuki; Baba, Kenji; Okuda, Masaru; Mizuno, Takuya

    2017-07-07

    A 16-year-old spayed female American Shorthair cat was presented with lethargy, anorexia, and wamble. Physical and blood examination did not reveal any remarkable findings. Abdominal ultrasonography identified the presence of a localized anechoic structure with a thick wall in contact with the small intestine and adjacent to the liver. Ultrasound-guided fine-needle aspiration of the structure revealed fluid containing numerous cocci and neutrophils. Two days after antibiotic treatment, exploratory laparotomy was performed and the content of the structure was removed before multiple lavages. The pathological and bacteriological examination results supported a confirmatory diagnosis of pancreatic abscess due to Staphylococcus aureus infection, making this the first such report in a cat. The cat remained healthy thereafter with no disease recurrence.

  11. Methicillin-resistant Staphylococcus Aureus Lip Infection Mimicking Angioedema.

    Science.gov (United States)

    Lucerna, Alan R; Espinosa, James; Darlington, Anne M

    2015-07-01

    It is rare for angioedema to be misidentified by the experienced clinician or for it to mimic another disease process. As an Emergency Physician, it is important to recognize and treat angioedema immediately. Of equal importance is the recognition and initiation of treatment of facial cellulitis. A case report follows that illustrates methicillin-resistant Staphylococcus aureus (MRSA) lip infection mimicking angioedema. Here, we describe a case of a 21-year-old man who presented with a swollen lower lip, initially diagnosed as angioedema. Further investigation revealed the cause of his lip swelling was actually a MRSA abscess and surrounding cellulitis, an unusual presentation for lip infection, which we discuss below. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Misidentifying MRSA lip infection for angioedema, with a delay in proper treatment, could result in serious morbidity or mortality. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Quorum sensing inhibitors of Staphylococcus aureus from Italian medicinal plants.

    Science.gov (United States)

    Quave, Cassandra L; Plano, Lisa R W; Bennett, Bradley C

    2011-01-01

    Morbidity and mortality estimates due to methicillin-resistant Staphylococcus aureus (MRSA) infections continue to rise. Therapeutic options are limited by antibiotic resistance. Anti-pathogenic compounds, which inhibit quorum sensing (QS) pathways, may be a useful alternative to antibiotics. Staphylococcal QS is encoded by the AGR locus and is responsible for the production of δ-hemolysin. Quantification of δ-hemolysin found in culture supernatants permits the analysis of AGR activity at the translational rather than transcriptional level. We employed reversed phase high performance chromatographic (RP-HPLC) techniques to investigate the anti-QS activity of 168 extracts from 104 Italian plants through quantification of δ-hemolysin. Extracts from three medicinal plants (Ballota nigra, Castanea sativa, and Sambucus ebulus) exhibited a dose-dependent response in the production of δ-hemolysin, indicating anti-QS activity in a pathogenic MRSA isolate. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Bilateral sudden sensorineural hearing loss in Staphylococcus aureus endocarditis.

    Science.gov (United States)

    Lau, Joanne Wai Ling; Ceranic, Borka; Harris, Robert; Timehin, Elwina

    2015-09-14

    This case highlights the diagnostic challenges in patients presenting with bilateral sudden sensorinueral hearing loss (SNHL). The aetiology of bilateral sudden SNHL may span several medical disciplines. Therefore, clinicians should be mindful of such presentations, and consider aetiologies beyond otological and neurological causes. We present a case of a previously healthy 51-year-old woman who presented with coryzal symptoms and sudden audiovestibular failure. Examination revealed fever, tachycardia, bilateral profound hearing loss and nystagmus. Following investigations, an initial working diagnosis of vasculitis was made. Later, blood cultures revealed methicillin-sensitive Staphylococcus aureus (MSSA) and a transoesophageal echocardiogram confirmed endocarditis. The patient made a good recovery, but the hearing loss was permanent and managed with a cochlear implant. 2015 BMJ Publishing Group Ltd.

  14. Global initiative for meticillin-resistant Staphylococcus aureus pneumonia (GLIMP)

    DEFF Research Database (Denmark)

    Aliberti, Stefano; Reyes, Luis F; Faverio, Paola

    2016-01-01

    BACKGROUND: Antibiotic resistance is a major global health problem and pathogens such as meticillin-resistant Staphylococcus aureus (MRSA) have become of particular concern in the management of lower respiratory tract infections. However, few data are available on the worldwide prevalence and risk...... with pneumonia who had microbiological tests taken within 24 h of presentation. We recruited investigators from 222 hospitals in 54 countries to gather point-prevalence data for all patients admitted with these characteristics during 4 days randomly selected during the months of March, April, May, and June...... in 2015. We assessed prevalence of MRSA pneumonia and associated risk factors through logistic regression analysis. FINDINGS: 3702 patients hospitalised with pneumonia were enrolled, with 3193 patients receiving microbiological tests within 24 h of admission, forming the patient population. 1173 (37%) had...

  15. Methicillin-resistant Staphylococcus aureus pneumonia in adults.

    Science.gov (United States)

    Woods, Christian; Colice, Gene

    2014-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has become one of the leading etiologies of nosocomial pneumonia as a result of an increase in staphylococcal infections caused by methicillin-resistant strains paired with extended ventilatory support of critically, and often, chronically ill patients. The prevalence of community-acquired MRSA pneumonia, which historically affects younger patients and is often preceded by an influenza-like illness, is also increasing. A high index of suspicion and early initiation of appropriate antibiotics are key factors for the successful treatment of this disease. Even with early diagnosis and appropriate treatment, MRSA pneumonia still carries an unacceptably high mortality rate. This article will review historical differences between hospital-acquired and community-acquired MRSA pneumonia, as well as, clinical features of, diagnosis and treatment of MRSA pneumonia.

  16. Pneumonia caused by methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Rubinstein, Ethan; Kollef, Marin H; Nathwani, Dilip

    2008-06-01

    A recent increase in staphylococcal infections caused by methicillin-resistant Staphylococcus aureus (MRSA), combined with frequent, prolonged ventilatory support of an aging, often chronically ill population, has resulted in a large increase in cases of MRSA pneumonia in the health care setting. In addition, community-acquired MRSA pneumonia has become more prevalent. This type of pneumonia historically affects younger patients, follows infection with influenza virus, and is often severe, requiring hospitalization and causing the death of a significant proportion of those affected. Ultimately, hospital-acquired MRSA and community-acquired MRSA are important causes of pneumonia and present diagnostic and therapeutic challenges. Rapid institution of appropriate antibiotic therapy, including linezolid as an alternative to vancomycin, is crucial. Respiratory infection-control measures and de-escalation of initial broad-spectrum antibiotic regimens to avoid emergence of resistant organisms are also important. This article reviews the clinical features of, diagnosis of, and therapies for MRSA pneumonia.

  17. Reversal of methicillin resistance in Staphylococcus aureus by thioridazine

    DEFF Research Database (Denmark)

    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....... mecA and the protein level of the encoded protein PBP2a. Methods Viability of MRSA was determined in liquid media in the presence of oxacillin or thioridazine alone or in combination. Transcription of mecA was analysed by primer extension, and the protein level of PBP2a was analysed by western...

  18. Karakterisasi Faktor-faktor Virulensi Staphylococcus aureus Asal Susu Kambing Peranakan Ettawa secara Fenotip dan Genotip

    Directory of Open Access Journals (Sweden)

    Khusnan Khusnan

    2017-02-01

    85,7% hydrophil. Staphylococcus aureus (85,7% isolates abled to aglutinated sheep blood cells. Based on genotypic analysis of Staphylococcus aureus could be detected coa gene (92,8%, clf gene (64,3%, fnbA gene (78,6%, and fnbB gene (64,3%. Based on the phenotypic and genotypic characters, it can be concluded that Staphylococcus aureus are virulent strains. This information can be used as the basis for control mastitis in PE goats

  19. Treatment of infections due to resistant Staphylococcus aureus.

    Science.gov (United States)

    Anstead, Gregory M; Cadena, Jose; Javeri, Heta

    2014-01-01

    This chapter reviews data on the treatment of infections caused by drug-resistant Staphylococcus aureus, particularly methicillin-resistant S. aureus (MRSA). This review covers findings reported in the English language medical literature up to January of 2013. Despite the emergence of resistant and multidrug-resistant S. aureus, we have seven effective drugs in clinical use for which little resistance has been observed: vancomycin, quinupristin-dalfopristin, linezolid, tigecycline, telavancin, ceftaroline, and daptomycin. However, vancomycin is less effective for infections with MRSA isolates that have a higher MIC within the susceptible range. Linezolid is probably the drug of choice for the treatment of complicated MRSA skin and soft tissue infections (SSTIs); whether it is drug of choice in pneumonia remains debatable. Daptomycin has shown to be non-inferior to either vancomycin or β-lactams in the treatment of staphylococcal SSTIs, bacteremia, and right-sided endocarditis. Tigecycline was also non-inferior to comparator drugs in the treatment of SSTIs, but there is controversy about whether it is less effective than other therapeutic options in the treatment of more serious infections. Telavancin has been shown to be non-inferior to vancomycin in the treatment of SSTIs and pneumonia, but has greater nephrotoxicity. Ceftaroline is a broad-spectrum cephalosporin with activity against MRSA; it is non-inferior to vancomycin in the treatment of SSTIs. Clindamycin, trimethoprim-sulfamethoxazole, doxycycline, rifampin, moxifloxacin, and minocycline are oral anti-staphylococcal agents that may have utility in the treatment of SSTIs and osteomyelitis, but the clinical data for their efficacy is limited. There are also several drugs with broad-spectrum activity against Gm-positive organisms that have reached the phase II and III stages of clinical testing that will hopefully be approved for clinical use in the upcoming years: oritavancin, dalbavancin, omadacycline

  20. Antimicrobial activity of essential oils against Staphylococcus aureus biofilms.

    Science.gov (United States)

    Vázquez-Sánchez, Daniel; Cabo, Marta L; Rodríguez-Herrera, Juan J

    2015-12-01

    The present study was aimed to evaluate the potential of essential oils to remove the foodborne pathogen Staphylococcus aureus from food-processing facilities. The effectiveness of 19 essential oils against planktonic cells of S. aureus was firstly assessed by minimal inhibitory concentration. Planktonic cells showed a wide variability in resistance to essential oils, with thyme oil as the most effective, followed by lemongrass oil and then vetiver oil. The eight essential oils most effective against planktonic cells were subsequently tested against 48-h-old biofilms formed on stainless steel. All essential oils reduced significantly (p oils were the most effective, but high concentrations were needed to achieve logarithmic reductions over 4 log CFU/cm(2) after 30 min exposure. Alternatively, the use of sub-lethal doses of thyme oil allowed to slow down biofilm formation and to enhance the efficiency of thyme oil and benzalkonium chloride against biofilms. However, some cellular adaptation to thyme oil was detected. Therefore, essential oil-based treatments should be based on the rotation and combination of different essential oils or with other biocides to prevent the emergence of antimicrobial-resistant strains. © The Author(s) 2014.

  1. Staphylococcus aureus infections: transmission within households and the community.

    Science.gov (United States)

    Knox, Justin; Uhlemann, Anne-Catrin; Lowy, Franklin D

    2015-07-01

    Staphylococcus aureus, both methicillin susceptible and resistant, are now major community-based pathogens worldwide. The basis for this is multifactorial and includes the emergence of epidemic clones with enhanced virulence, antibiotic resistance, colonization potential, or transmissibility. Household reservoirs of these unique strains are crucial to their success as community-based pathogens. Staphylococci become resident in households, either as colonizers or environmental contaminants, increasing the risk for recurrent infections. Interactions of household members with others in different households or at community sites, including schools and daycare facilities, have a critical role in the ability of these strains to become endemic. Colonization density at these sites appears to have an important role in facilitating transmission. The integration of research tools, including whole-genome sequencing (WGS), mathematical modeling, and social network analysis, has provided additional insight into the transmission dynamics of these strains. Thus far, interventions designed to reduce recurrent infections among household members have had limited success, likely due to the multiplicity of potential sources for recolonization. The development of better strategies to reduce the number of household-based infections will depend on greater insight into the different factors that contribute to the success of these uniquely successful epidemic clones of S. aureus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Multidrug Efflux Pumps in Staphylococcus aureus: an Update

    Science.gov (United States)

    Costa, Sofia Santos; Viveiros, Miguel; Amaral, Leonard; Couto, Isabel

    2013-01-01

    The emergence of infections caused by multi- or pan-resistant bacteria in the hospital or in the community settings is an increasing health concern. Albeit there is no single resistance mechanism behind multiresistance, multidrug efflux pumps, proteins that cells use to detoxify from noxious compounds, seem to play a key role in the emergence of these multidrug resistant (MDR) bacteria. During the last decades, experimental data has established their contribution to low level resistance to antimicrobials in bacteria and their potential role in the appearance of MDR phenotypes, by the extrusion of multiple, unrelated compounds. Recent studies suggest that efflux pumps may be used by the cell as a first-line defense mechanism, avoiding the drug to reach lethal concentrations, until a stable, more efficient alteration occurs, that allows survival in the presence of that agent. In this paper we review the current knowledge on MDR efflux pumps and their intricate regulatory network in Staphylococcus aureus, a major pathogen, responsible from mild to life-threatening infections. Particular emphasis will be given to the potential role that S. aureus MDR efflux pumps, either chromosomal or plasmid-encoded, have on resistance towards different antimicrobial agents and on the selection of drug - resistant strains. We will also discuss the many questions that still remain on the role of each specific efflux pump and the need to establish appropriate methodological approaches to address all these questions. PMID:23569469

  3. Characterization of transcription within sdr region of Staphylococcus aureus.

    Science.gov (United States)

    Sitkiewicz, Izabela; Babiak, Ireneusz; Hryniewicz, Waleria

    2011-02-01

    Staphylococcus aureus is an opportunistic pathogen responsible for various infections in humans and animals. It causes localized and systemic infections, such as abscesses, impetigo, cellulitis, sepsis, endocarditis, bone infections, and meningitis. S. aureus virulence factors responsible for the initial contact with host cells (MSCRAMMs-microbial surface components recognizing adhesive matrix molecules) include three Sdr proteins. The presence of particular sdr genes is correlated with putative tissue specificity. The transcriptional organization of the sdr region remains unclear. We tested expression of the sdrC, sdrD, or sdrE genes in various in vitro conditions, as well as after contact with human blood. In this work, we present data suggesting a separation of the sdr region into three transcriptional units, based on their differential reactions to the environment. Differential reaction of the sdrD transcript to environmental conditions and blood suggests dissimilar functions of the sdr genes. SdrE has been previously proposed to play role in bone infections, whilst our results can indicate that sdrD plays a role in the interactions between the pathogen and human immune system, serum or specifically reacts to nutrients/other factors present in human blood.

  4. Expression of Four Methionine Sulfoxide Reductases in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Kuldeep Singh

    2012-01-01

    Full Text Available Staphylococcus aureus possesses three MsrA enzymes (MsrA1, MsrA2, MsrA3 that reduce the S-epimer of methionine sulfoxide (MetO and an MsrB enzyme that reduces R-MetO. The four msr genes are expressed from three different promoters. The msrA1/msrB genes are coexpressed. To determine the expression pattern of msr genes, three independent reporter strains were constructed where msr promoter was cloned in front of a promoterless lacZ and the resulting construct was integrated in the chromosome. Using these strains, it was determined that the msrA1/B expression is significantly higher in S. aureus compared to msrA2 or msrA3. Expression of msrA1/B was highest during stationary phase growth, but the expression of msrA2 and msrA3 was highest during the early to midexponential growth phase. Expression of msrA1/B was induced by oxacillin and the expression of msrA3 was upregulated by salt. Expression of msrA2 remained unchanged under all tested conditions.

  5. METHICILLIN - RESISTANT STAPHYLOCOCCUS AUREUS IN PIG PRODUCTION CHAIN

    Directory of Open Access Journals (Sweden)

    M. Conter

    2012-08-01

    Full Text Available The aims of this study were (i to estimate the prevalence of Staphylococcus aureus (S.a in pig farm environments; (ii to evaluate the presence of S.a in pork processing environments (iii to detect the presence of methicillin-resistant (MRSA among isolated strains. Samples of pig stool, farm environment and pork processing environment were collected. These samples were submitted to detection of S.a following the international method: UNI EN ISO 6888-2 and the Minimum Inhibitory Concentrations (MIC tests were performed by using the automated VITEK 2 system. In addition, a PCR for the detection of the mecA gene was applied. Overall, S. aureus were more frequently detected from pig farms than from pork processing environments. Among the n.51 isolated strains, n. 49 (96% were methicillin resistant (MRSA and only n.2 strains were methicillin sensitive (MSSA. The results of the present study highlighted that further studies are needed to elucidate transmission routes of MRSA in pig production chain.

  6. Adhesion force of staphylococcus aureus on various biomaterial surfaces.

    Science.gov (United States)

    Alam, Fahad; Balani, Kantesh

    2017-01-01

    Staphylococcus comprises of more than half of all pathogens in orthopedic implant infections and they can cause major bone infection which can result in destruction of joint and bone. In the current study, adhesion force of bacteria on the surface of various biomaterial surfaces is measured using atomic force microscope (AFM). Staphylococcus aureus was immobilized on an AFM tipless cantilever as a force probe to measure the adhesion force between bacteria and biomaterials (viz. ultra-high molecular weight poly ethylene (UHMWPE), stainless steel (SS), Ti-6Al-4V alloy, hydroxyapatite (HA)). At the contact time of 10s, UHMWPE shows weak adhesion force (~4nN) whereas SS showed strong adhesion force (~15nN) due to their surface energy and surface roughness. Bacterial retention and viability experiment (3M™ petrifilm test, agar plate) dictates that hydroxyapatite shows the lowest vaibility of bacteria, whereas lowest bacterial retention is observed on UHMWPE surface. Similar results were obtained from live/dead staining test, where HA shows 65% viability, whereas on UHMWPE, SS and Ti-6Al-4V, the bacterial viability is 78%, 94% and 97%, respectively. Lower adhesion forces, constrained pull-off distance (of bacterial) and high antibacterial resistance of bioactive-HA makes it a potential biomaterial for bone-replacement arthroplasty. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Emerging drugs on methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Liapikou, Adamantia; Torres, Antoni

    2013-09-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has proven to be a prominent pathogen in hospitals and in the community, which is capable of causing a variety of severe infections. Until now, there has been a limited antimicrobial armamentarium for use against MRSA, of which glycopeptides and linezolid are the main agents used. This review assesses current treatment and the agents being developed for MRSA infections. A search was conducted in PubMed for English-language references published from 2000 to 2013, using combinations of the following terms: 'MRSA', 'MRSA therapy', 'gram (+) infections therapy', 'new antibiotics', 'vancomycin', 'staphylococcus resistance', 'oritavancin', 'ceftaroline', 'linezolid' and 'tigecycline'. The clinicalTrials website was also searched with keywords regarding the new antibiotic agents against MRSA infections. There are a number of new agents, the place of which in therapeutic regimens is yet to emerge. New glycopeptides, such as dalbavancin and oritavancin, with long half-lives, enabling once-weekly dosing, and oral agents, such as iclaprim, may provide a treatment approach for outpatient therapy. A decision must be made regarding the most suitable agent for an individual patient, the site of infection and the place of therapy.

  8. Staphylococcus aureus α-Toxin: Nearly a Century of Intrigue

    Science.gov (United States)

    Berube, Bryan J.; Bubeck Wardenburg, Juliane

    2013-01-01

    Staphylococcus aureus secretes a number of host-injurious toxins, among the most prominent of which is the small β-barrel pore-forming toxin α-hemolysin. Initially named based on its properties as a red blood cell lytic toxin, early studies suggested a far greater complexity of α-hemolysin action as nucleated cells also exhibited distinct responses to intoxication. The hemolysin, most aptly referred to as α-toxin based on its broad range of cellular specificity, has long been recognized as an important cause of injury in the context of both skin necrosis and lethal infection. The recent identification of ADAM10 as a cellular receptor for α-toxin has provided keen insight on the biology of toxin action during disease pathogenesis, demonstrating the molecular mechanisms by which the toxin causes tissue barrier disruption at host interfaces lined by epithelial or endothelial cells. This review highlights both the historical studies that laid the groundwork for nearly a century of research on α-toxin and key findings on the structural and functional biology of the toxin, in addition to discussing emerging observations that have significantly expanded our understanding of this toxin in S. aureus disease. The identification of ADAM10 as a proteinaceous receptor for the toxin not only provides a greater appreciation of truths uncovered by many historic studies, but now affords the opportunity to more extensively probe and understand the role of α-toxin in modulation of the complex interaction of S. aureus with its human host. PMID:23888516

  9. Repurposing salicylanilide anthelmintic drugs to combat drug resistant Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Rajmohan Rajamuthiah

    Full Text Available Staphylococcus aureus is a Gram-positive bacterium that has become the leading cause of hospital acquired infections in the US. Repurposing Food and Drug Administration (FDA approved drugs for antimicrobial therapy involves lower risks and costs compared to de novo development of novel antimicrobial agents. In this study, we examined the antimicrobial properties of two commercially available anthelmintic drugs. The FDA approved drug niclosamide and the veterinary drug oxyclozanide displayed strong in vivo and in vitro activity against methicillin resistant S. aureus (minimum inhibitory concentration (MIC: 0.125 and 0.5 μg/ml respectively; minimum effective concentration: ≤ 0.78 μg/ml for both drugs. The two drugs were also effective against another Gram-positive bacteria Enterococcus faecium (MIC 0.25 and 2 μg/ml respectively, but not against the Gram-negative species Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter aerogenes. The in vitro antimicrobial activity of niclosamide and oxyclozanide were determined against methicillin, vancomycin, linezolid or daptomycin resistant S. aureus clinical isolates, with MICs at 0.0625-0.5 and 0.125-2 μg/ml for niclosamide and oxyclozanide respectively. A time-kill study demonstrated that niclosamide is bacteriostatic, whereas oxyclozanide is bactericidal. Interestingly, oxyclozanide permeabilized the bacterial membrane but neither of the anthelmintic drugs exhibited demonstrable toxicity to sheep erythrocytes. Oxyclozanide was non-toxic to HepG2 human liver carcinoma cells within the range of its in vitro MICs but niclosamide displayed toxicity even at low concentrations. These data show that the salicylanilide anthelmintic drugs niclosamide and oxyclozanide are suitable candidates for mechanism of action studies and further clinical evaluation for treatment of staphylococcal infections.

  10. Repurposing salicylanilide anthelmintic drugs to combat drug resistant Staphylococcus aureus.

    Science.gov (United States)

    Rajamuthiah, Rajmohan; Fuchs, Beth Burgwyn; Conery, Annie L; Kim, Wooseong; Jayamani, Elamparithi; Kwon, Bumsup; Ausubel, Frederick M; Mylonakis, Eleftherios

    2015-01-01

    Staphylococcus aureus is a Gram-positive bacterium that has become the leading cause of hospital acquired infections in the US. Repurposing Food and Drug Administration (FDA) approved drugs for antimicrobial therapy involves lower risks and costs compared to de novo development of novel antimicrobial agents. In this study, we examined the antimicrobial properties of two commercially available anthelmintic drugs. The FDA approved drug niclosamide and the veterinary drug oxyclozanide displayed strong in vivo and in vitro activity against methicillin resistant S. aureus (minimum inhibitory concentration (MIC): 0.125 and 0.5 μg/ml respectively; minimum effective concentration: ≤ 0.78 μg/ml for both drugs). The two drugs were also effective against another Gram-positive bacteria Enterococcus faecium (MIC 0.25 and 2 μg/ml respectively), but not against the Gram-negative species Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter aerogenes. The in vitro antimicrobial activity of niclosamide and oxyclozanide were determined against methicillin, vancomycin, linezolid or daptomycin resistant S. aureus clinical isolates, with MICs at 0.0625-0.5 and 0.125-2 μg/ml for niclosamide and oxyclozanide respectively. A time-kill study demonstrated that niclosamide is bacteriostatic, whereas oxyclozanide is bactericidal. Interestingly, oxyclozanide permeabilized the bacterial membrane but neither of the anthelmintic drugs exhibited demonstrable toxicity to sheep erythrocytes. Oxyclozanide was non-toxic to HepG2 human liver carcinoma cells within the range of its in vitro MICs but niclosamide displayed toxicity even at low concentrations. These data show that the salicylanilide anthelmintic drugs niclosamide and oxyclozanide are suitable candidates for mechanism of action studies and further clinical evaluation for treatment of staphylococcal infections.

  11. Staphylococcus aureus α-Toxin: Nearly a Century of Intrigue

    Directory of Open Access Journals (Sweden)

    Bryan J. Berube

    2013-06-01

    Full Text Available Staphylococcus aureus secretes a number of host-injurious toxins, among the most prominent of which is the small β-barrel pore-forming toxin α-hemolysin. Initially named based on its properties as a red blood cell lytic toxin, early studies suggested a far greater complexity of α-hemolysin action as nucleated cells also exhibited distinct responses to intoxication. The hemolysin, most aptly referred to as α-toxin based on its broad range of cellular specificity, has long been recognized as an important cause of injury in the context of both skin necrosis and lethal infection. The recent identification of ADAM10 as a cellular receptor for α-toxin has provided keen insight on the biology of toxin action during disease pathogenesis, demonstrating the molecular mechanisms by which the toxin causes tissue barrier disruption at host interfaces lined by epithelial or endothelial cells. This review highlights both the historical studies that laid the groundwork for nearly a century of research on α-toxin and key findings on the structural and functional biology of the toxin, in addition to discussing emerging observations that have significantly expanded our understanding of this toxin in S. aureus disease. The identification of ADAM10 as a proteinaceous receptor for the toxin not only provides a greater appreciation of truths uncovered by many historic studies, but now affords the opportunity to more extensively probe and understand the role of α-toxin in modulation of the complex interaction of S. aureus with its human host.

  12. Clinical Risk Factors for Infective Endocarditis in Staphylococcus aureus Bacteremia.

    Science.gov (United States)

    Salvador, Vincent Bryan D; Chapagain, Bikash; Joshi, Astha; Brennessel, Debra J

    2017-02-01

    Crucial to the management of staphylococcal bacteremia is an accurate evaluation of associated endocarditis, which has both therapeutic and prognostic implications. Because the clinical presentation of endocarditis can be nonspecific, the judicious use of echocardiography is important in distinguishing patients at high risk of developing endocarditis. In the presence of high-risk clinical features, an early transesophageal echocardiogram is warranted without prior transthoracic echocardiography. The purpose of this study was to investigate the clinical risk factors for staphylococcal infective endocarditis that might warrant earlier transesophageal echocardiography and to describe the incidence of endocarditis in cases of methicillin-resistant and methicillin-sensitive Staphylococcus aureus bacteremia. A retrospective case-control study was conducted by means of chart review of 91 patients consecutively admitted to a community hospital from January 2009 through January 2013. Clinical risk factors of patients with staphylococcal bacteremia were compared with risk factors of patients who had definite diagnoses of infective endocarditis. There were 69 patients with bacteremia alone (76%) and 22 patients with endocarditis (24%), as verified by echocardiography. Univariate analysis showed that diabetes mellitus ( P =0.024), the presence of an automatic implantable cardioverter-defibrillator/pacemaker ( P =0.006) or a prosthetic heart valve ( P =0.003), and recent hospitalization ( P =0.048) were significantly associated with developing infective endocarditis in patients with S. aureus bacteremia. The incidence of methicillin-resistant and methicillin-sensitive S. aureus bacteremia was similar in the bacteremia and infective-endocarditis groups ( P =0.437). In conclusion, identified high-risk clinical factors in the presence of bacteremia can suggest infective endocarditis. Early evaluation with transesophageal echocardiography might well be warranted.

  13. Mobilization of Genomic Islands of Staphylococcus aureus by Temperate Bacteriophage

    Science.gov (United States)

    Moon, Bo Youn; Park, Joo Youn; Robinson, D. Ashley; Thomas, Jonathan C.; Park, Yong Ho; Thornton, Justin A.; Seo, Keun Seok

    2016-01-01

    The virulence of Staphylococcus aureus, in both human and animal hosts, is largely influenced by the acquisition of mobile genetic elements (MGEs). Most S. aureus strains carry a variety of MGEs, including three genomic islands (νSaα, νSaβ, νSaγ) that are diverse in virulence gene content but conserved within strain lineages. Although the mobilization of pathogenicity islands, phages and plasmids has been well studied, the mobilization of genomic islands is poorly understood. We previously demonstrated the mobilization of νSaβ by the adjacent temperate bacteriophage ϕSaBov from strain RF122. In this study, we demonstrate that ϕSaBov mediates the mobilization of νSaα and νSaγ, which are located remotely from ϕSaBov, mostly to recipient strains belonging to ST151. Phage DNA sequence analysis revealed that chromosomal DNA excision events from RF122 were highly specific to MGEs, suggesting sequence-specific DNA excision and packaging events rather than generalized transduction by a temperate phage. Disruption of the int gene in ϕSaBov did not affect phage DNA excision, packaging, and integration events. However, disruption of the terL gene completely abolished phage DNA packing events, suggesting that the primary function of temperate phage in the transfer of genomic islands is to allow for phage DNA packaging by TerL and that transducing phage particles are the actual vehicle for transfer. These results extend our understanding of the important role of bacteriophage in the horizontal transfer and evolution of genomic islands in S. aureus. PMID:26953931

  14. Methicillin-resistant Staphylococcus aureus: a controversial food-borne pathogen.

    Science.gov (United States)

    Sergelidis, D; Angelidis, A S

    2017-06-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of severe healthcare-associated (HA) infections. Although during the last decade the incidence of HA invasive infections has dropped, the incidence of community-associated MRSA (CA-MRSA) infections has risen among the general population. Moreover, CA-MRSA, livestock-associated MRSA (LA-MRSA) and HA-MRSA (HA-MRSA) can be found in foods intended for human consumption. Several studies from different geographical areas have reported the presence of enterotoxin genes in several MRSA food isolates. Molecular typing studies have revealed genetic relatedness of these enterotoxigenic isolates with isolates incriminated in human infections. The contamination sources for foods, especially animal-origin foods, may be livestock as well as humans involved in animal husbandry and food-processing. Under favourable environmental conditions for growth and enterotoxin production, enterotoxigenic S. aureus isolates present in foods can cause staphylococcal food poisoning (SFP), irrespective of the contamination origin. Owing to the typically moderate clinical manifestations of SFP, the S. aureus strains responsible for SFP (cases or outbreaks) are frequently either not identified or not further characterized. Antimicrobial susceptibility testing is rarely performed, because administration of antimicrobial therapy is not required in the vast majority of cases. Staphylococcal food poisoning is the result of consumption of foods with preformed enterotoxins. Hence, similar to methicillin-sensitive enterotoxigenic S. aureus, enterotoxigenic MRSA can also act as food-borne pathogens upon favourable conditions for growth and enterotoxin production. The severity of the intoxication is not related to the antimicrobial resistance profile of the causative S. aureus strain and therefore MRSA food-borne outbreaks are not expected to be more severe. This review evaluates the potential of methicillin-resistant Staphylococcus

  15. Relationship between Vancomycin-Resistant Staphylococcus aureus, Vancomycin-Intermediate S. aureus, High Vancomycin MIC, and Outcome in Serious S. aureus Infections

    OpenAIRE

    Holmes, Natasha E.; Johnson, Paul D. R.; Howden, Benjamin P.

    2012-01-01

    Vancomycin has been used successfully for over 50 years for the treatment of Staphylococcus aureus infections, particularly those involving methicillin-resistant S. aureus. It has proven remarkably reliable, but its efficacy is now being questioned with the emergence of strains of S. aureus that display heteroresistance, intermediate resistance, and, occasionally, complete vancomycin resistance. More recently, an association has been established between poor outcome and infections with strain...

  16. Secretome analysis defines the major role of SecDF in Staphylococcus aureus virulence.

    Directory of Open Access Journals (Sweden)

    Chantal Quiblier

    Full Text Available The Sec pathway plays a prominent role in protein export and membrane insertion, including the secretion of major bacterial virulence determinants. The accessory Sec constituent SecDF has been proposed to contribute to protein export. Deletion of Staphylococcus aureus secDF has previously been shown to reduce resistance, to alter cell separation, and to change the expression of certain virulence factors. To analyse the impact of the secDF deletion in S. aureus on protein secretion, a quantitative secretome analysis was performed. Numerous Sec signal containing proteins involved in virulence were found to be decreased in the supernatant of the secDF mutant. However, two Sec-dependent hydrolases were increased in comparison to the wild type, suggesting additional indirect, regulatory effects to occur upon deletion of secDF. Adhesion, invasion, and cytotoxicity of the secDF mutant were reduced in human umbilical vein endothelial cells. Virulence was significantly reduced using a Galleria mellonella insect model. Altogether, SecDF is a promising therapeutic target for controlling S. aureus infections.

  17. Antibiotic-mediated selection of quorum-sensing-negative Staphylococcus aureus

    DEFF Research Database (Denmark)

    Paulander, Wilhelm Erik Axel; Varming, Anders Nissen; Bæk, Kristoffer Torbjørn

    2012-01-01

    -acquired S. aureus infections and suggest that the adaptability of S. aureus to antibiotics involves the agr locus. IMPORTANCE: Staphylococcus aureus is the most frequently isolated pathogen in intensive care units and a common cause of nosocomial infections, resulting in a high degree of morbidity......Staphylococcus aureus is a human commensal that at times turns into a serious bacterial pathogen causing life-threatening infections. For the delicate control of virulence, S. aureus employs the agr quorum-sensing system that, via the intracellular effector molecule RNAIII, regulates virulence gene...... increases the agr-mediated fitness cost by inducing the expression of RNAIII. Thus, the extensive use of antibiotics in hospitals may explain why agr-negative variants are frequently isolated from hospital-acquired S. aureus infections but rarely found among community-acquired S. aureus strains. Importantly...

  18. Genomic organization of a vancomycin-resistant staphylococcus aureus

    International Nuclear Information System (INIS)

    Mirani, A.Z.; Jamil, N.

    2013-01-01

    Objective: To study the genomic organization of vancomycin resistance in a local isolate of vancomycin resistant Staphylococcus aureus (VRSA). Study Design: Experimental study. Place and Duration of Study: Department of Microbiology, University of Karachi, January 2008 through December 2010. Methodology: A vancomycin-resistant Staphylococcus aureus (VRSA-CP2) isolate (MIC 16 mu g/ml) was isolated from a local hospital of Karachi. Species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc gene. The vancomycin MIC was re-confirmed by E-test. For the genetic determination of vancomycin resistance, in-vitro amplification of vanA cassette was performed by using plasmid DNA of CP2, CP2's transformant as template on MWG Thermo-Cycler. Amplified products of vanR, vanS, vanH, vanA, vanY, orf2, orf1D, orf2E, orf-Rev and IS element genes were subjected to Sanger's electrophoresis based sequence determination using specific primers. The Basic Local Alignment Search Tool (BLAST) algorithm was used to identify sequences in GenBank with similarities to the vanA cassette genes. Results: The vancomycin-resistant isolate CP2 was found to be resistant to oxacillin, chloramphenicol, erythromycin, rifampicin, gentamicin, tetracycline and ciprofloxacin, as well. The isolate CP2 revealed four bands: one of large molecular size approx 56.4 kb and three of small size approx 6.5 kb, approx 6.1 kb and approx 1.5 kb by agarose gel electrophoresis indicating the presence of 3 plasmids. The plasmid DNA of isolate CP2 was analyzed by PCR for the presence of the van cassettes with each of the vanA , vanB and vanC specific primers. It carried vanA cassette, which comprises of vanR, vanS, vanH, vanA, vanY, and orf2. The vanA cassette of isolate CP2 also carried an insertion element (IS). However, it did not show the PCR product for orf1. Vancomycin resistance was successfully transferred from the donor CP2 to a vancomycin-sensitive recipient S

  19. Occurrence and antimicrobial resistance of Staphylococcus aureus in bulk tank milk and milk filters

    Directory of Open Access Journals (Sweden)

    Kateřina Bogdanovičová

    2014-02-01

    Full Text Available This work is focused on the monitoring of Staphylococcus aureus prevalence in raw milk and milk filters, its antibiotic resistance and detection of methicillin resistant Staphylococcus aureus (MRSA. Samples of raw cow´s milk and milk filters were collected in the period from 2012 till 2014, from 50 dairy farms in the Czech Republic. The total of 261 samples (164 samples of raw milk and 97 milk filters were cultivated on Baird-Parker agar. Both the typical and atypical colonies were examined by plasmacoagulase test and PCR method was used for detection of species specific fragment SA442 and mecA gene. Standard disk diffusion method was used to determinate resistance to antimicrobial agents. The bacterium Staphylococcus aureus was detected on 25 farms (50%. The antimicrobial resistance showed differences between the farms. Total of 58 samples were positive for Staphylococcus aureus, of which were 37 (14.2% isolated from raw milk samples and 21 (8.1% from milk filters. From these samples we isolated 62 Staphylococcus aureus strains, 41 isolates bacteria S. aureus from raw milk (66.1% and 21 isolates S. aureus from milk filters (33.9%. The presence of antibiotic resistance in Staphylococcus aureus isolates was low, most of them were resistant to amoxicilin. According to the results obtained by the PCR method for the methicillin - resistant S. aureus (MRSA, the mecA gene was present in 6 strains (9.7%, 4 isolates obtained from milk samples (6.5% and 2 isolates from milk filters (3.2%.  These isolates can be considered as a possible source of resistance genes, which can be spread through the food chain. Nowadays, a globally unfavourable increasing trend of prevalence of methicillin resistant staphylococci strains especially Staphylococcus aureus is being observed worldwide. The improper hygiene and poor farm management practices contributed to the presence of S. aureus in the milk. This may have contributed to the high level of S. aureus isolated

  20. Clinical significance of Staphylococcus aureus bacteriuria in a nationwide study of adults with S. aureus bacteraemia.

    Science.gov (United States)

    Asgeirsson, Hilmir; Kristjansson, Mar; Kristinsson, Karl G; Gudlaugsson, Olafur

    2012-01-01

    To evaluate the clinical significance of Staphylococcus aureus bacteriuria (SABU) in adults with S. aureus bacteraemia (SAB). All individuals ≥18 years old diagnosed with SAB in Iceland between December 1st 2003 and November 30th 2008 were retrospectively identified. Data was collected from medical records. Concomitant SABU was defined as growth of S. aureus in a urine sample taken within 24 h of the index blood culture. SABU was seen in 27 of 166 (16.3%) SAB patients having urine cultured before administration of antibiotics, but after excluding those with SAB of urinary tract origin SABU was seen in 16 of 152 (10.5%). In this latter cohort SABU was independently associated with having endocarditis (RR 6.68; 95% CI 1.53-17.3) and admission to intensive-care unit (RR 2.84; 95% CI 1.25-4.44), while for having complicated SAB the RR was 1.56 (95% CI 0.96-1.80). No correlation was seen with mortality or relapse rates. SABU appears to be secondary to SAB in some cases while it is the primary infection causing SAB in others. In patients with SAB of non-urinary tract origin SABU should probably be regarded as distant haematogenous seeding and a marker of deep tissue dissemination, thus affecting general management and treatment duration. Copyright © 2011 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  1. Concomitant genotyping revealed diverse spreading between methicillin-resistant Staphylococcus aureus and methicillin-susceptible Staphylococcus aureus in central Taiwan.

    Science.gov (United States)

    Ho, Cheng-Mao; Lin, Chien-Yu; Ho, Mao-Wang; Lin, Hsiao-Chuan; Peng, Ching-Tien; Lu, Jang-Jih

    2016-06-01

    Staphylococcus aureus is a versatile bacterium, which can lead to various infectious diseases. Various molecular typing methods are applied to the evolution and epidemiology surveys of S. aureus, mostly for methicillin-resistant S. aureus (MRSA). However, methicillin-susceptible S. aureus (MSSA) is still an important pathogen, but their molecular typing is evaluated infrequently. Pulsed-field gel electrophoresis (PFGE), spa typing, and detection of five virulent genes for 95 MRSA and 56 MSSA isolates (July-December 2008 and July 2008-December 2009, respectively) during an overlapping period were performed. More diversity was found in MSSA isolates (23 pulsotypes and 25 spa types, excluding 4 new-type and 1 nontypable isolates for spa typing) than in MRSA isolates (19 pulsotypes and 16 spa types, excluding 1 new-type and 1 nontypable isolates for spa typing). By spa typing, t002 (n = 30), t037 (n = 23), t437 (n = 21), t234 (n = 3), t1081 (n = 3), and t1094 (n = 3) were the six major MRSA clones. For MSSA isolates, t189 (n = 13), t437 (n = 4), t084 (n = 3), t213 (n = 3), t701 (n = 3), and t7200 (n = 3) were the six major types. Combining PFGE and spa typing, there were five combinations (pulsotype + spa type) that contained both MRSA and MSSA isolates (pulsotype 9-t437, pulsotype 15-t037, pulsotype 19-t002, pulsotype 21-t002, and pulsotype 28-t1081). For all 151 S. aureus or 95 MRSA isolates, the PFGE typing had more discrimination power, but spa typing had larger discrimination index for 56 MSSA isolates. In conclusion, there were different predominant MRSA and MSSA clones clinically. Continuing longitudinal tracking of molecular typing is necessary for elucidating the evolution of this important clinical pathogen. Copyright © 2014. Published by Elsevier B.V.

  2. ASSOCIATION OF CHRONIC NASAL CARRIAGE OF STAPHYLOCOCCUS-AUREUS AND HIGHER RELAPSE RATES IN WEGENER GRANULOMATOSIS

    NARCIS (Netherlands)

    Stegeman, Coen; Tervaert, J.W.C.; Sluiter, W.J.; Manson, W.L.; DEJONG, P.E.; Kallenberg, Cees

    1994-01-01

    Objective: To examine possible risk factors for relapse, including chronic nasal carriage of Staphylococcus aureus and serial antineutrophil cytoplasmic antibody (ANCA) determinations in patients with Wegener granulomatosis. Design: Observational cohort study. Setting: Outpatient clinic at a

  3. Transmission of Methicillin-Resistant Staphylococcus aureus between Human and Hamster▿

    OpenAIRE

    Ferreira, Jorge Pinto; Fowler, Vance G.; Correa, Maria T.; Lyman, Roberta; Ruffin, Felicia; Anderson, Kevin L.

    2011-01-01

    Transmission of methicillin-resistant Staphylococcus aureus (MRSA) between humans and animals is increasingly recognized. We newly document that the transmission of MRSA between human and hamster is possible.

  4. Transmission of methicillin-resistant Staphylococcus aureus between human and hamster.

    Science.gov (United States)

    Ferreira, Jorge Pinto; Fowler, Vance G; Correa, Maria T; Lyman, Roberta; Ruffin, Felicia; Anderson, Kevin L

    2011-04-01

    Transmission of methicillin-resistant Staphylococcus aureus (MRSA) between humans and animals is increasingly recognized. We newly document that the transmission of MRSA between human and hamster is possible.

  5. Transmission of methicillin-resistant Staphylococcus aureus from food production animals to humans: a review

    NARCIS (Netherlands)

    Broens, E.M.; Cleef, van B.A.G.L.; Graat, E.A.M.; Kluytmans, J.A.J.W.

    2008-01-01

    International surveillance of antimicrobial use in food animal production shows that methicillinresistant Staphylococcus aureus (MRSA), traditionally a human pathogen associated with hospitals, has emerged in the community and animals. Since 1961, MRSA has been causing human infections in hospitals

  6. Nasopharyngeal co-colonization with Staphylococcus aureus and Streptococcus pneumoniae in children is bacterial genotype independent.

    NARCIS (Netherlands)

    Melles, D.C.; Bogaert, D.; Gorkink, R.F.; Peeters, J.K.; Moorhouse, M.J.; Ott, A.; Leeuwen, W.B. van; Simons, G.; Verbrugh, H.A.; Hermans, P.W.M.; Belkum, A. van

    2007-01-01

    Bacterial interference between Staphylococcus aureus and Streptococcus pneumoniae in the nasopharynx has been observed during colonization, which might have important clinical implications for the widespread use of pneumococcal conjugate vaccine in young children. This study aimed to determine

  7. Natural population dynamics and expansion of pathogenic clones of Staphylococcus aureus

    NARCIS (Netherlands)

    D.C. Melles (Damian); R.F.J. Gorkink (Raymond); H.A.M. Boelens (Hélène); S.V. Snijders (Susan); J.K. Peeters (Justine); M.J. Moorhouse (Michael); P.J. van der Spek (Peter); W.B. van Leeuwen (Willem); G. Simons (Guus); H.A. Verbrugh (Henri); A.F. van Belkum (Alex)

    2004-01-01

    textabstractThe population structure of Staphylococcus aureus carried by healthy humans was determined using a large strain collection of nonclinical origin (n = 829). High-throughput amplified fragment length polymorphism (AFLP) analysis revealed 3 major and 2 minor genetic

  8. The Lytic SA Phage Demonstrate Bactericidal Activity against Mastitis Causing Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Hamza Ameer

    2016-01-01

    Full Text Available Staphylococcus aureus is the major causative agent of mastitis among dairy animals as it causes intramammary gland infection. Due to antibiotic resistance and contamination of antibiotics in the milk of diseased animals; alternative therapeutic agents are required to cure mastitis. Lytic bacteriophages and their gene products can be potential therapeutic agents against bacteria as they are host specific and less harmful than antibiotics. In this study, Staphylococcus aureus were isolated from milk samples of the infected animals and identified biochemically. SA phage was isolated from sewage water showing lytic activity against Staphylococcus aureus isolates. The highest lytic activity of bacteriophages was observed at 37°C and pH 7, and the most suitable storage condition was at 4°C. SA phage efficiently reduced bacterial growth in the bacterial reduction assay. The characterization and bacterial growth reduction activity of the bacteriophages against Staphylococcus aureus signifies their underlying potential of phage therapy against mastitis.

  9. Prevention of meticillin-resistant Staphylococcus aureus bloodstream infections in European hospitals: moving beyond policies

    NARCIS (Netherlands)

    Borg, M.A.; Hulscher, M.; Scicluna, E.A.; Richards, J.; Azanowsky, J.M.; Xuereb, D.; Huis, A. van; Moro, M.L.; Maltezou, H.C.; Frank, U.

    2014-01-01

    BACKGROUND: There is evidence that meticillin-resistant Staphylococcus aureus (MRSA) bacteraemia can be reduced with improved infection control and antibiotic stewardship. AIM: To survey infection control and antibiotic stewardship practices within European hospitals and to identify initiatives that

  10. Linear peptidomimetics as potent antagonists of Staphylococcus aureus agr quorum sensing

    DEFF Research Database (Denmark)

    Karathanasi, Georgia; Bojer, Martin Saxtorph; Baldry, Mara

    2018-01-01

    Staphylococcus aureus is an important pathogen causing infections in humans and animals. Increasing problems with antimicrobial resistance has prompted the development of alternative treatment strategies, including antivirulence approaches targeting virulence regulation such as the agr quorum...

  11. Classification of Epidemic Community-Acquired Methicillin-Resistant Staphylococcus aureus by Anatomical Site of Isolation

    Directory of Open Access Journals (Sweden)

    Jill C. Roberts

    2014-01-01

    Full Text Available Methicillin-resistant Staphylococcus aureus contributes significantly to cost, morbidity, and mortality due to infectious disease. We surveyed community-associated MRSA isolates to determine which strains were present within anatomical sites of interest. The most likely sources of MRSA among anatomic sites swabbed were wounds followed by the nasal cavity. The USA 300 MRSA strain was most commonly isolated among wound infections while nasal swabs largely yielded USA 100 MRSA. The frequency of isolation of USA 100 amongst community-associated strains is clinically significant as this strain is often correlated with invasive disease, exhibits broad antibiotic resistance, and has been considered to be hospital associated. The potential of USA 100 to cause serious disease and the frequency of its isolation suggest an important reservoir for opportunistic infection. These data demonstrate that MRSA epidemic clones are widespread among the community.

  12. Preoperative Staphylococcus Aureus Screening and Targeted Decolonization in Cardiac Surgery.

    Science.gov (United States)

    Saraswat, Manoj K; Magruder, Jonathan T; Crawford, Todd C; Gardner, Julia M; Duquaine, Damon; Sussman, Marc S; Maragakis, Lisa L; Whitman, Glenn J

    2017-10-01

    We assessed the impact of preoperative Staphylococcus aureus screening and targeted decolonization on the incidence of postoperative methicillin-resistant S aureus (MRSA) colonization, intensive care unit MRSA transmission, and surgical site infections in cardiac surgery patients. We reviewed medical records for all adult patients during two periods: preintervention (January 2007 to April 2010) and intervention (January 2011 to December 2014). In the intervention period, we performed nasal screening for methicillin-sensitive S aureus and MRSA using polymerase chain reaction within 30 days of the operation. Colonized patients received intranasal mupirocin twice daily and chlorhexidine baths daily for 5 days; patients colonized with MRSA also received prophylactic vancomycin plus cefazolin with contact isolation precautions. Nasal surveillance for MRSA was performed on intensive care unit admission and weekly thereafter. Multivariable logistic regression models were constructed to determine risk factors for postoperative MRSA colonization, and surgical site infections and the impact of our screening program was assessed in these models. Poisson regression was used to assess MRSA transmission. Comparing 2,826 preintervention and 4,038 intervention patients, cases differed in age, diabetes mellitus, preoperative infection, preoperative length of stay, and bypass time (all p ≤ 0.03). Intervention patients had risk-adjusted reductions in MRSA colonization (odds ratio 0.53, 95% confidence interval [CI]: 0.37 to 0.76, p transmission (incidence rate ratio 0.29, 95% CI: 0.13 to 0.65, p = 0.002), and surgical site infections (odds ratio 0.58, 95% CI: 0.40 to 0.86, p = 0.007). Increased duration of preoperative decolonization therapy was associated with decreased postoperative MRSA colonization (odds ratio 0.73, 95% CI: 0.53 to 1.00, p = 0.05). Preoperative S aureus screening with targeted decolonization was associated with reduced MRSA colonization, transmission, and

  13. Local circulating clones of Staphylococcus aureus in Ecuador.

    Science.gov (United States)

    Zurita, Jeannete; Barba, Pedro; Ortega-Paredes, David; Mora, Marcelo; Rivadeneira, Sebastián

    The spread of pandemic Staphylococcus aureus clones, mainly methicillin-resistant S. aureus (MRSA), must be kept under surveillance to assemble an accurate, local epidemiological analysis. In Ecuador, the prevalence of the USA300 Latin American variant clone (USA300-LV) is well known; however, there is little information about other circulating clones. The aim of this work was to identify the sequence types (ST) using a Multiple-Locus Variable number tandem repeat Analysis 14-locus genotyping approach. We analyzed 132 S. aureus strains that were recovered from 2005 to 2013 and isolated in several clinical settings in Quito, Ecuador. MRSA isolates composed 46.97% (62/132) of the study population. Within MRSA, 37 isolates were related to the USA300-LV clone (ST8-MRSA-IV, Panton-Valentine Leukocidin [PVL] +) and 10 were related to the Brazilian clone (ST239-MRSA-III, PVL-). Additionally, two isolates (ST5-MRSA-II, PVL-) were related to the New York/Japan clone. One isolate was related to the Pediatric clone (ST5-MRSA-IV, PVL-), one isolate (ST45-MRSA-II, PVL-) was related to the USA600 clone, and one (ST22-MRSA-IV, PVL-) was related to the epidemic UK-EMRSA-15 clone. Moreover, the most prevalent MSSA sequence types were ST8 (11 isolates), ST45 (8 isolates), ST30 (8 isolates), ST5 (7 isolates) and ST22 (6 isolates). Additionally, we found one isolate that was related to the livestock associated S. aureus clone ST398. We conclude that in addition to the high prevalence of clone LV-ST8-MRSA-IV, other epidemic clones are circulating in Quito, such as the Brazilian, Pediatric and New York/Japan clones. The USA600 and UK-EMRSA-15 clones, which were not previously described in Ecuador, were also found. Moreover, we found evidence of the presence of the livestock associated clone ST398 in a hospital environment. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

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

    OpenAIRE

    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...

  15. Formulasi Salep Ekstrak Etanol Cacing Tanah (Peryonix sp.) dan Uji Aktivitasnya Terhadap Bakteri Staphylococcus Aureus

    OpenAIRE

    Lubis, Aji Muhiddin

    2016-01-01

    Infectious diseases of the skin still is one of the most disease suffered by people in developing countries. One cause of the skin infection disease is a bacterial such as Staphylococcus aureus. Earthworms have traditionally been widely used to treat diseases caused by bacteria. Earthworms Peryonix sp have been studied have anti-infection activity against Staphylococcus aureus that commonly found on the skin surface. The purpose of this research was to create a suitable ointment formulations ...

  16. Long-term mortality after Staphylococcus aureus spondylodiscitis

    DEFF Research Database (Denmark)

    Aagaard, Theis; Roed, Casper; Larsen, Anders R

    2014-01-01

    Patients diagnosed with Staphylococcus aureus spondylodiscitis have increased long-term mortality compared with the background population mainly due to infectious, endocrine, cardiovascular, gastrointestinal and alcohol and drug abuse-related diseases.......Patients diagnosed with Staphylococcus aureus spondylodiscitis have increased long-term mortality compared with the background population mainly due to infectious, endocrine, cardiovascular, gastrointestinal and alcohol and drug abuse-related diseases....

  17. Evaluation of fusidic acid in therapy of experimental Staphylococcus aureus meningitis

    DEFF Research Database (Denmark)

    Østergaard, Christian; Yieng-Kow, Runa Vavia; Knudsen, Jenny Dahl

    2003-01-01

    Combination therapy that includes fusidic acid, an antimicrobial agent highly active against staphylococci, has been recommended in the treatment of patients with Staphylococcus aureus meningitis. The aim of this study was to evaluate the pharmacokinetic, CSF bactericidal and anti-inflammatory pr......Combination therapy that includes fusidic acid, an antimicrobial agent highly active against staphylococci, has been recommended in the treatment of patients with Staphylococcus aureus meningitis. The aim of this study was to evaluate the pharmacokinetic, CSF bactericidal and anti...

  18. Development of the immune response in pneumonia due to Staphylococcus aureus (part 2

    Directory of Open Access Journals (Sweden)

    A.E. Abaturov

    2017-04-01

    Full Text Available The article analyzes the role of pattern-recognition receptors involved in recognition of pathogen-associated molecular patterns of Staphylococcus aureus. There are shown the basic operation of macrophage and monocyte NLRP3, NLRC5, NLRP7, AIM2 inflammasomes that form the active forms of pro-inflammatory cytokines IL-1-beta and IL-18 du-ring the development of pneumonia caused by Staphylococcus aureus.

  19. First isolation of methicillin-resistant Staphylococcus aureus from pigs’ clinical samples in Serbia

    Directory of Open Access Journals (Sweden)

    Milenko Zutic

    2012-01-01

    Full Text Available Methicillin-resistant Staphylococcus aureus is a highly important human pathogen that is also a significant concern in veterinary medicine. Despite the high prevalence of colonization, clinical infections with methicillin-resistant Staphylococcus aureus appear to be rare in pigs. Methicillin-resistant Staphylococcus aureus was isolated from a sow with endometritis and her five piglets with dermatitis originating from a Serbian farm. Identification of the strains was done by automated system and confirmed by polymerase chain reaction for mecA and nuc genes. Detection of Staphylococcal Cassette Chromosome mec type was performed by multiplex polymerase chain reaction. Antimicrobial susceptibility testing on erythromycin, clindamycin, gentamicin, kanamycin, tobramycin, ciprofloxacin, tetracycline, trimethoprim/sulfamethoxazole and vancomycin was done by disc diffusion method. Six isolated strains from the infected sow and her piglets showed resistance only to tetracycline beside resistance to all beta-lactam antibiotics. In the tested methicillin-resistant Staphylococcus aureus isolates, Staphylococcal Cassette Chromosome mec type V was present. To our knowledge, this finding is the first documented detection of methicillin-resistant Staphylococcus aureus from pigs’ clinical samples in Serbia. The results of our study indicate the emergence of methicillin-resistant Staphylococcus aureus in a pig farm in Serbia highlighting the threat of this antibiotic-resistant microorganism as a pathogen causing both animal and human infections.

  20. Biochemical and Molecular Analysis of Staphylococcus aureus Clinical Isolates from Hospitalized Patients

    Directory of Open Access Journals (Sweden)

    Amit Karmakar

    2016-01-01

    Full Text Available Staphylococcus aureus is opportunistic human as well as animal pathogen that causes a variety of diseases. A total of 100 Staphylococcus aureus isolates were obtained from clinical samples derived from hospitalized patients. The presumptive Staphylococcus aureus clinical isolates were identified phenotypically by different biochemical tests. Molecular identification was done by PCR using species specific 16S rRNA primer pairs and finally 100 isolates were found to be positive as Staphylococcus aureus. Screened isolates were further analyzed by several microbiological diagnostics tests including gelatin hydrolysis, protease, and lipase tests. It was found that 78%, 81%, and 51% isolates were positive for gelatin hydrolysis, protease, and lipase activities, respectively. Antibiogram analysis of isolated Staphylococcus aureus strains with respect to different antimicrobial agents revealed resistance pattern ranging from 57 to 96%. Our study also shows 70% strains to be MRSA, 54.3% as VRSA, and 54.3% as both MRSA and VRSA. All the identified isolates were subjected to detection of mecA, nuc, and hlb genes and 70%, 84%, and 40% were found to harbour mecA, nuc, and hlb genes, respectively. The current investigation is highly important and informative for the high level multidrug resistant Staphylococcus aureus infections inclusive also of methicillin and vancomycin.

  1. Are Nasal Carriers of Staphylococcus aureus More Likely To Become Colonized or Infected with Methicillin-Resistant Staphylococcus aureus on Admission to a Hospital?▿

    OpenAIRE

    Krebes, Juliane; Al-Ghusein, Hasan; Feasey, Nick; Breathnach, Aodhan; Lindsay, Jodi A.

    2010-01-01

    Of 840 patients at hospital admission, 2.7% were positive for methicillin-resistant Staphylococcus aureus (MRSA) and 22.3% were positive for methicillin-susceptible S. aureus (MSSA). During the next 8 months, 4.8% of the MSSA-positive patients acquired MRSA with no lineage association. A total of 5.2% of noncarriers acquired MRSA. We find no evidence that colonized hosts are more susceptible to acquiring MRSA.

  2. Livestock-associated Staphylococcus aureus on Polish pig farms

    Science.gov (United States)

    Mroczkowska, Aneta; Żmudzki, Jacek; Marszałek, Natalia; Orczykowska-Kotyna, Monika; Komorowska, Iga; Nowak, Agnieszka; Grzesiak, Anna; Czyżewska-Dors, Ewelina; Dors, Arkadiusz; Pejsak, Zygmunt; Hryniewicz, Waleria; Wyszomirski, Tomasz; Empel, Joanna

    2017-01-01

    Background Livestock-associated Staphylococcus aureus (LA-SA) draws increasing attention due to its particular ability to colonize farm animals and be transmitted to people, which in turn leads to its spread in the environment. The aim of the study was to determine the dissemination of LA-SA on pig farms selected throughout Poland, characterize the population structure of identified S. aureus, and assess the prevalence of LA-SA carriage amongst farmers and veterinarians being in contact with pigs. Methods and findings The study was conducted on 123 pig farms (89 farrow-to-finish and 34 nucleus herds), located in 15 out of 16 provinces of Poland. Human and pig nasal swabs, as well as dust samples were analyzed. S. aureus was detected on 79 (64.2%) farms from 14 provinces. Amongst these farms LA-SA-positive farms dominated (71/79, 89.9%, 95% CI [81.0%, 95.5%]). The prevalence of LA-MRSA-positive farms was lower than LA-MSSA-positive (36.6% of LA-SA-positive farms, 95% CI [25.5%, 48.9%] vs. 74.6%, 95% CI [62.9%, 84.2%]). In total, 190 S. aureus isolates were identified: 72 (38%) MRSA and 118 (62%) methicillin-susceptible S. aureus (MSSA), of which 174 (92%) isolates were classified to three livestock-associated lineages: CC398 (73%), CC9 (13%), and CC30/ST433 (6%). All CC398 isolates belonged to the animal clade. Four LA-MRSA clones were detected: ST433-IVa(2B) clone (n = 8, 11%), described to the best of our knowledge for the first time, and three ST398 clones (n = 64, 89%) with the most prevalent being ST398-V(5C2&5)c, followed by ST398-V(5C2), and ST398-IVa(2B). Nasal carriage of LA-SA by pig farmers was estimated at 13.2% (38/283), CC398 carriage at 12.7% (36/283) and ST398-MRSA carriage at 3.2% (9/283), whereas by veterinarians at 21.1% (8/38), 18.4% (7/38) and 10.5% (4/38), respectively. Conclusions The prevalence of LA-MRSA-positive pig farms in Poland has increased considerably since 2008, when the first MRSA EU baseline survey was conducted in Europe. On

  3. Livestock-associated Staphylococcus aureus on Polish pig farms.

    Science.gov (United States)

    Mroczkowska, Aneta; Żmudzki, Jacek; Marszałek, Natalia; Orczykowska-Kotyna, Monika; Komorowska, Iga; Nowak, Agnieszka; Grzesiak, Anna; Czyżewska-Dors, Ewelina; Dors, Arkadiusz; Pejsak, Zygmunt; Hryniewicz, Waleria; Wyszomirski, Tomasz; Empel, Joanna

    2017-01-01

    Livestock-associated Staphylococcus aureus (LA-SA) draws increasing attention due to its particular ability to colonize farm animals and be transmitted to people, which in turn leads to its spread in the environment. The aim of the study was to determine the dissemination of LA-SA on pig farms selected throughout Poland, characterize the population structure of identified S. aureus, and assess the prevalence of LA-SA carriage amongst farmers and veterinarians being in contact with pigs. The study was conducted on 123 pig farms (89 farrow-to-finish and 34 nucleus herds), located in 15 out of 16 provinces of Poland. Human and pig nasal swabs, as well as dust samples were analyzed. S. aureus was detected on 79 (64.2%) farms from 14 provinces. Amongst these farms LA-SA-positive farms dominated (71/79, 89.9%, 95% CI [81.0%, 95.5%]). The prevalence of LA-MRSA-positive farms was lower than LA-MSSA-positive (36.6% of LA-SA-positive farms, 95% CI [25.5%, 48.9%] vs. 74.6%, 95% CI [62.9%, 84.2%]). In total, 190 S. aureus isolates were identified: 72 (38%) MRSA and 118 (62%) methicillin-susceptible S. aureus (MSSA), of which 174 (92%) isolates were classified to three livestock-associated lineages: CC398 (73%), CC9 (13%), and CC30/ST433 (6%). All CC398 isolates belonged to the animal clade. Four LA-MRSA clones were detected: ST433-IVa(2B) clone (n = 8, 11%), described to the best of our knowledge for the first time, and three ST398 clones (n = 64, 89%) with the most prevalent being ST398-V(5C2&5)c, followed by ST398-V(5C2), and ST398-IVa(2B). Nasal carriage of LA-SA by pig farmers was estimated at 13.2% (38/283), CC398 carriage at 12.7% (36/283) and ST398-MRSA carriage at 3.2% (9/283), whereas by veterinarians at 21.1% (8/38), 18.4% (7/38) and 10.5% (4/38), respectively. The prevalence of LA-MRSA-positive pig farms in Poland has increased considerably since 2008, when the first MRSA EU baseline survey was conducted in Europe. On Polish pig farms CC398 of the animal clade

  4. Fresh garlic extract inhibits Staphylococcus aureus biofilm formation under chemopreventive and chemotherapeutic conditions

    Directory of Open Access Journals (Sweden)

    Panan Ratthawongjirakul

    2016-08-01

    Full Text Available Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA are the leading aetiological pathogens of nosocomial infections worldwide. These bacteria form biofilms on both biotic and abiotic surfaces causing biofilm-associated infections. Within the biofilm, these bacteria might develop persistent and antimicrobial resistant characteristics resulting in chronic infections and treatment failures. Garlic exhibits broad pharmaceutical properties and inhibitory activities against S. aureus. We investigated the effects of aqueous fresh garlic extract on biofilm formation in S. aureus ATCC25923 and MRSA strains under chemopreventive and chemotherapeutic conditions. The viable bacteria and biofilm levels were quantified through colony count and crystal violet staining, respectively. The use of fresh garlic extract under both conditions significantly inhibited biofilm formation in S. aureus strains ATCC25923 and MRSA. Garlic could be developed as either a prophylactic or therapeutic agent to manage S. aureus biofilm-associated infections.

  5. Human-associated methicillin-resistant Staphylococcus aureus from a subtropical recreational marine beach

    Science.gov (United States)

    Reports of Staphylococcus aureus detected in marine environments have occurred since the early 1990’s. This investigation sought to isolate and characterize S. aureus from marine waters and sand at a subtropical recreational beach, with and without bathers present, in order to investigate possible s...

  6. Neonatal colonization with Staphylococcus aureus is not associated with development of atopic dermatitis

    DEFF Research Database (Denmark)

    Skov, L; Halkjaer, L B; Agner, T

    2009-01-01

    BACKGROUND: Staphylococcus aureus in atopic skin has been associated with exacerbation of eczema. Objectives To investigate a possible association between neonatal colonization with S. aureus and the risk of atopic dermatitis (AD) during the first 3 years of life. MATERIALS AND METHODS: The study...

  7. High genetic diversity of Staphylococcus aureus strains colonizing patients with epidermolysis bullosa

    NARCIS (Netherlands)

    van der Kooi-Pol, Magdalena M.; Veenstra-Kyuchukova, Yanka K.; Duipmans, Jose C.; Pluister, Gerlinde N.; Schouls, Leo M.; de Neeling, Albert J.; Grundmann, Hajo; Jonkman, Marcel F.; van Dijl, Jan Maarten

    Patients with the blistering disease, epidermolysis bullosa (EB), frequently suffer from chronic wounds that become colonized by pathogenic bacteria, such as Staphylococcus aureus. To determine S.similar to aureus colonization rates in patients with EB, swabs were collected from the anterior nares,

  8. Molecular Characterization of Staphylococcus aureus Isolates Transmitted between Patients with Buruli Ulcer

    NARCIS (Netherlands)

    Amissah, Nana Ama; Chlebowicz, Monika A.; Ablordey, Anthony; Sabat, Artur J.; Tetteh, Caitlin S.; Prah, Isaac; van der Werf, Tjip S.; Friedrich, Alex W.; van Dijl, Jan Maarten; Rossen, John W.; Stienstra, Ymkje

    Background Buruli ulcer (BU) is a skin infection caused by Mycobacterium ulcerans. The wounds of most BU patients are colonized with different microorganisms, including Staphylococcus aureus. Methodology This study investigated possible patient-to-patient transmission events of S. aureus during

  9. Natural Antibodies in Normal Human Serum Inhibit Staphylococcus aureus Capsular Polysaccharide Vaccine Efficacy

    OpenAIRE

    Skurnik, David; Kropec, Andrea; Roux, Damien; Theilacker, Christian; Huebner, Johannes; Pier, Gerald B.

    2012-01-01

    Antibodies to Staphylococcus aureus capsular polysaccharides (CP) and poly-N-acetyl glucosamine (PNAG) antigens interfere in protection. Active immunization of mice failed to overcome interference. Natural nonprotective antibodies to PNAG in normal human serum may prevent effective vaccination against S. aureus CP antigens.

  10. Clonal structure of Staphylococcus aureus colonizing children with sickle cell anaemia and healthy controls

    NARCIS (Netherlands)

    Schaumburg, F.; Biallas, B.; Alabi, A. S.; Grobusch, M. P.; Feugap, E. N.; Lell, B.; Mellmann, A.; Peters, G.; Kremsner, P. G.; Becker, K.; Adegnika, A. A.

    2013-01-01

    Children with sickle cell anaemia (SCA) might carry hospital-associated bacterial lineages due to frequent hospital stays and antibiotic treatments. In this study we compared Staphylococcus aureus from SCA patients (n=73) and healthy children (n=143) in a cross-sectional study in Gabon. S. aureus

  11. Community-associated methicillin-resistant Staphylococcus aureus causing orbital cellulitis in Australian children.

    Science.gov (United States)

    Vaska, Vikram L; Grimwood, Keith; Gole, Glen A; Nimmo, Graeme R; Paterson, David L; Nissen, Michael D

    2011-11-01

    Community-associated methicillin-resistant Staphylococcus aureus has only emerged recently as a cause of serious ocular infections in several different countries. At a tertiary pediatric hospital in Brisbane, Australia, community-associated methicillin-resistant S. aureus orbital cellulitis was first noted in 2009. Since then, it has caused 4 of 9 such infections.

  12. In vitro characterization of representative clinical South African Staphylococcus aureus isolates from various clonal lineages

    NARCIS (Netherlands)

    Oosthuysen, W F; Orth, H; Lombard, C. J.; Sinha, B; Wasserman, E

    Data concerning the virulence and pathogenesis of South African strains of Staphylococcus aureus are limited. We investigated host-pathogen interactions of randomly selected clinical S. aureus isolates representing various clones. We characterized the ability of isolates to adhere to fibronectin,

  13. Influence of antibiotic pressure on bacterial bioluminescence, with emphasis on Staphylococcus aureus

    NARCIS (Netherlands)

    Daghighi, Seyedmojtaba; Sjollema, Jelmer; Harapanahalli, Akshay; Dijkstra, Rene J. B.; van der Mei, Henny C.; Busscher, Henk J.

    2015-01-01

    Bioluminescence imaging is used for longitudinal evaluation of bacteria in live animals. Clear relations exist between bacterial numbers and their bioluminescence. However, bioluminescence images of Staphylococcus aureus Xen29, S. aureus Xen36 and Escherichia coli Xen14 grown on tryptone soy agar in

  14. Nigribactin, a Novel Siderophore from Vibrio nigripulchritudo, Modulates Staphylococcus aureus Virulence Gene Expression

    DEFF Research Database (Denmark)

    Nielsen, Anita; Månsson, Maria; Wietz, Matthias

    2012-01-01

    Staphylococcus aureus is a serious human pathogen that employs a number of virulence factors as part of its pathogenesis. The purpose of the present study was to explore marine bacteria as a source of compounds that modulate virulence gene expression in S. aureus. During the global marine Galathe...

  15. Host adaptation of bovine Staphylococcus aureus seems associated with bacteriological cure after lactational antimicrobial treatment

    NARCIS (Netherlands)

    Borne, van den B.H.P.; Nielen, M.; Schaik, van G.; Melchior, M.B.; Lam, T.J.G.M.; Zadoks, R.N.

    2010-01-01

    Staphylococcus aureus causes a wide range of diseases in multiple species. Some sequence types (ST) are observed in a variety of hosts, whereas other strains are mainly associated with bovine mastitis, suggesting host adaptation. We propose that host adaptation of Staph. aureus may influence

  16. Mupirocin prophylaxis against nosocomial Staphylococcus aureus infections in nonsurgical patients: a randomized study.

    NARCIS (Netherlands)

    Wertheim, H.F.; Vos, A.M.C.; Ott, A.; Voss, A.; Kluytmans, J.A.J.W.; Vandenbroucke-Grauls, C.M.; Meester, M.; Keulen, P.H. van; Verbrugh, H.A.

    2004-01-01

    BACKGROUND: Staphylococcus aureus nasal carriage is a major risk factor for nosocomial S. aureus infection. Studies show that intranasal mupirocin can prevent nosocomial surgical site infections. No data are available on the efficacy of mupirocin in nonsurgical patients. OBJECTIVE: To assess the

  17. Mupirocin prophylaxis against nosocomial Staphylococcus aureus infections in nonsurgical patients: a randomized study

    NARCIS (Netherlands)

    Wertheim, Heiman F. L.; Vos, Margreet C.; Ott, Alewijn; Voss, Andreas; Kluytmans, Jan A. J. W.; Vandenbroucke-Grauls, Christina M. J. E.; Meester, Marlene H. M.; van Keulen, Peter H. J.; Verbrugh, Henri A.

    2004-01-01

    BACKGROUND: Staphylococcus aureus nasal carriage is a major risk factor for nosocomial S. aureus infection. Studies show that intranasal mupirocin can prevent nosocomial surgical site infections. No data are available on the efficacy of mupirocin in nonsurgical patients. OBJECTIVE: To assess the

  18. The adhesive and immunomodulating properties of the multifunctional Staphylococcus aureus protein Eap

    NARCIS (Netherlands)

    Harraghy, Niamh; Hussain, Muzaffar; Haggar, Axana; Chavakis, Triantafyllos; Sinha, Bhanu; Herrmann, Mathias; Flock, Jan-Ingmar

    2003-01-01

    Adherence of Staphylococcus aureus to the host tissue is an important step in the initiation of pathogenesis. At least 10 adhesins produced by S. aureus have been described and it is becoming clear that the expression of these adhesins and their interactions with eukaryotic cells involve complex

  19. Nosocomial Staphylococcus Aureus Bacterimia among Nasal Carriers of Methicillin- Resistant and Methicillin-Susceptible Strains

    NARCIS (Netherlands)

    M. Pujol (Miquel); C. Pena; R. Pallares (Roman); J. Ariza (Javier); J. Ayats (Josefina); M.A. Dominguez; F. Gudiol (Francesc)

    1996-01-01

    textabstractObjectives To determine the relevance of nasal carriage of Staphylococcus aureus, either methicillin-sensitive (MSSA) or methicillinresistant (MRSA), as a risk factor for the development of nosocomial S aureus bacteremia during an MRSA outbreak. patients and methods: In this prospective

  20. The molecular evolution of hospital- and community-associated methicillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    Deurenberg, Ruud H; Stobberingh, Ellen E

    Staphylococcus aureus can cause a wide variety of infections, ranging from minor skin infections to post-operative wound infections. Its adaptive power to antibiotics has resulted in the emergence of methicillin-resistant S. aureus (MRSA) in the beginning of the 1960s. Resistance to methicillin and

  1. Patients with Methicillin-Resistant Staphylococcus aureus (MRSA) Infection – 21st Century Lepers

    OpenAIRE

    Mozzillo, Kristin L.; Ortiz, Nancy; Miller, Loren G.

    2010-01-01

    In the recent past, there has been a dramatic increase in the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections, especially community-associated methicillin-resistant S. aureus (CA-MRSA) infections. Many media descriptions of MRSA are sensational and focus on its potential for severe disease and contagiousness.

  2. Requirement of the agr Locus for Colony Spreading of Staphylococcus aureus

    NARCIS (Netherlands)

    Tsompanidou, Eleni; Sibbald, Mark J. J. B.; Chlebowicz, Monika A.; Dreisbach, Annette; Back, Jaap Willem; van Dijl, Jan Maarten; Buist, Girbe; Denham, Emma L.

    The important human pathogen Staphylococcus aureus is known to spread on soft agar plates. Here, we show that colony spreading of S. aureus involves the agr quorum-sensing system. This finding can be related to the agr-dependent expression of biosurfactants, such as phenol-soluble modulins,

  3. Development of a Standard Test to Assess the Resistance of Staphylococcus aureus Biofilm Cells to Disinfectants

    NARCIS (Netherlands)

    Luppens, S.B.I.; Reij, M.W.; Heijden, van der R.W.; Rombouts, F.M.; Abee, T.

    2002-01-01

    A standardized disinfectant test for Staphylococcus aureus cells in biofilms was developed. Two disinfectants, the membrane-active compound benzalkonium chloride (BAC) and the oxidizing agent sodium hypochlorite, were used to evaluate the biofilm test. S. aureus formed biofilms on glass, stainless

  4. A systematic review and meta-analysis on Staphylococcus aureus carriage in psoriasis, acne and rosacea

    NARCIS (Netherlands)

    J. Totté (Joan); W.T. van der Feltz; L.G.M. Bode (Lonneke); A.F. van Belkum (Alex); E.J. Van Zuuren; S.G.M.A. Pasmans (Suzanne)

    2016-01-01

    textabstractStaphylococcus aureus might amplify symptoms in chronic inflammatory skin diseases. This study evaluates skin and mucosal colonization with S. aureus in patients with psoriasis, acne and rosacea. A systematic literature search was conducted. Both odds ratios (OR) for colonization in

  5. Non-spa-typeable clinical Staphylococcus aureus strains are naturally occurring protein A mutants

    DEFF Research Database (Denmark)

    Baum, Cathrin; Haslinger-Löffler, Bettina; Westh, Henrik

    2009-01-01

    Staphylococcus aureus is a major human pathogen responsible for increasing the prevalence of community- and hospital-acquired infections. Protein A (SpA) is a key virulence factor of S. aureus and is highly conserved. Sequencing of the variable-number tandem-repeat region of SpA (spa typing) prov...

  6. Triple-acting antimicrobial treatment for drug-resistant and intracellular Staphylococcus aureus.

    Science.gov (United States)

    Multi-drug resistant bacteria are a persistent problem in modern health care, food safety and animal health. There is a need for new antimicrobials to replace over-used conventional antibiotics. Staphylococcus aureus (S. aureus) is a notorious pathogen for both animal and human health with multi-d...

  7. Draft genome sequences of 14 Staphylococcus aureus ST5 isolates from California, USA

    Science.gov (United States)

    Staphylococcus aureus is a bacteria that can cause disease in humans and animals. S. aureus bacteria can transfer or exchange segments of genetic material with other bacteria. These segments are known as mobile genetic elements and in some instances they can encode for factors that increase the abil...

  8. Complete genome sequences of two Staphylococcus aureus ST5 isolates from California, USA

    Science.gov (United States)

    Staphylococcus aureus is a bacteria that can cause disease in humans and animals. S. aureus bacteria can transfer or exchange segments of genetic material with other bacteria. These segments are known as mobile genetic elements and in some instances they can encode for factors that increase the abil...

  9. Physicochemical characterization of Staphylococcus aureus-lysing LysK enzyme in complexes with polycationic

    Science.gov (United States)

    Staphylococcus aureus causes many serious visceral, skin, and respiratory diseases. About 90% of clinical strains are multi-drug resistant, but the use of bacteriophage lytic enzymes offers a viable alternative to antibiotic therapy. LysK, the phage K endolysin can lyse S. aureus when purified and ...

  10. High genetic diversity among community-associated Staphylococcus aureus in Europe

    DEFF Research Database (Denmark)

    Rolo, Joana; Miragaia, Maria; Turlej-Rogacka, Agata

    2012-01-01

    Several studies have addressed the epidemiology of community-associated Staphylococcus aureus (CA-SA) in Europe; nonetheless, a comprehensive perspective remains unclear. In this study, we aimed to describe the population structure of CA-SA and to shed light on the origin of methicillin-resistant S....... aureus (MRSA) in this continent....

  11. Methicillin-Resistant "Staphylococcus aureus" on Campus: A New Challenge to College Health

    Science.gov (United States)

    Weiner, H. Richard

    2008-01-01

    As new drugs to control bacterial pathogens are developed, the organisms evolve to survive. "Staphylococcus aureus", a common organism, has steadily developed resistance to antibiotics. For more than 40 years, resistant "S. aureus" presented a formidable problem to hospitalized patients; in the past decade, however, it has begun to appear outside…

  12. Methicillin-resistant and -susceptible Staphylococcus aureus sequence type 398 in pigs and humans.

    NARCIS (Netherlands)

    Belkum, A. van; Melles, D.C.; Peeters, J.K.; Leeuwen, W.B. van; Duijkeren, E. van; Huijsdens, X.W.; Spalburg, E.; Neeling, A.J. de; Verbrugh, H.A.

    2008-01-01

    Methicillin-resistant Staphylococcus aureus sequence type 398 (ST398 MRSA) was identified in Dutch pigs and pig farmers. ST398 methicillin-susceptible S. aureus circulates among humans at low frequency (0.2%) but was isolated in 3 human cases of bacteremia (2.1%; p = 0.026). Although its natural

  13. Carriage frequency, diversity and methicillin resistance of Staphylococcus aureus in Danish small ruminants

    DEFF Research Database (Denmark)

    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...

  14. Emergence of methicillin-resistant Staphylococcus aureus (MRSA) in different animal species

    NARCIS (Netherlands)

    Cuny, Christiane; Friedrich, Alexander; Kozytska, Svetlana; Layer, Franziska; Nübel, Ulrich; Ohlsen, Knut; Strommenger, Birgit; Walther, Birgit; Wieler, Lothar; Witte, Wolfgang

    The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in animals such as horses, pet animals and productive livestock has raised questions of a probable human origin and in more general of host specificity of S. aureus. Particular clonal lineages are obviously specific for humans (e.g.

  15. Unraveling the dynamics of community-associated methicillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    Bootsma, M.C.; Bonten, M.J.M.

    2013-01-01

    Since the first description of the community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strain USA300 [1] in the 1990s, this pathogen has emerged worldwide [2]. Within a decade, USA300 has become the most prevalent cause of community-acquired S. aureus infections in many

  16. Distinct Roles of Phenol-Soluble Modulins in Spreading of Staphylococcus aureus on Wet Surfaces

    NARCIS (Netherlands)

    Tsompanidou, Eleni; Denham, Emma L.; Becher, Doerte; de Jong, Anne; Buist, Girbe; van Oosten, Marleen; Manson, Willem L.; Back, Jaap Willem; van Dijl, Jan Maarten; Dreisbach, Annette

    The human pathogen Staphylococcus aureus is renowned for the rapid colonization of contaminated wounds, medical implants, and food products. Nevertheless, little is known about the mechanisms that allow S. aureus to colonize the respective wet surfaces. The present studies were therefore aimed at

  17. Virulence and antimicrobial resistance of Staphylococcus aureus isolated from bloodstream infections and pneumonia in Southern Poland

    NARCIS (Netherlands)

    Pomorska-Wesolowska, Monika; Chmielarczyk, Agnieszka; Chlebowicz, Monika; Ziolkowski, Grzegorz; Szczypta, Anna; Natkaniec, Joanna; Romaniszyn, Dorota; Pobiega, Monika; Dzikowska, Miroslawa; Krawczyk, Lech; Koziol, Joanna; Wojkowska-Mach, Jadwiga

    2017-01-01

    Objectives: Staphylococcus aureus remains the most important cause of infections in hospitals and long-term care facilities. The aim of this study was to analyse the resistance, virulence, and epidemiological and genetic relationships of S. aureus from bloodstream infections (BSIs) and pneumonia

  18. Polymorphism, genetic exchange and intragenic recombination of the aureolysin gene among Staphylococcus aureus strains

    NARCIS (Netherlands)

    Sabat, Artur J.; Wladyka, Benedykt; Kosowska-Shick, Klaudia; Grundmann, Hajo; van Dijl, Jan Maarten; Kowal, Julia; Appelbaum, Peter C.; Dubin, Adam; Hryniewicz, Waleria

    2008-01-01

    Background: Staphylococcus aureus expresses several proteases, which are thought to contribute to the virulence of this bacterium. Here we focus on aureolysin, the major thermolysin-like metalloprotease. Despite the importance of aureolysin in the physiology and pathogenesis of S. aureus, relatively

  19. Norlichexanthone Reduces Virulence Gene Expression and Biofilm Formation in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Baldry, Mara; Nielsen, Anita; Bojer, Martin S.

    2016-01-01

    Staphylococcus aureus is a serious human pathogen and antibiotic resistant, community-associated strains, such as the methicillin resistant S. aureus (MRSA) strain USA300, continue to spread. To avoid resistance, anti-virulence therapy has been proposed where toxicity is targeted rather than...

  20. Global changes in Staphylococcus aureus gene expression in human blood.

    Directory of Open Access Journals (Sweden)

    Natalia Malachowa

    2011-04-01

    Full Text Available Staphylococcus aureus is a leading cause of bloodstream infections worldwide. In the United States, many of these infections are caused by a strain known as USA300. Although progress has been made, our understanding of the S. aureus molecules that promote survival in human blood and ultimately facilitate metastases is incomplete. To that end, we analyzed the USA300 transcriptome during culture in human blood, human serum, and trypticase soy broth (TSB, a standard laboratory culture media. Notably, genes encoding several cytolytic toxins were up-regulated in human blood over time, and hlgA, hlgB, and hlgC (encoding gamma-hemolysin subunits HlgA, HlgB, and HlgC were among the most highly up-regulated genes at all time points. Compared to culture supernatants from a wild-type USA300 strain (LAC, those derived from an isogenic hlgABC-deletion strain (LACΔhlgABC had significantly reduced capacity to form pores in human neutrophils and ultimately cause neutrophil lysis. Moreover, LACΔhlgABC had modestly reduced ability to cause mortality in a mouse bacteremia model. On the other hand, wild-type and LACΔhlgABC strains caused virtually identical abscesses in a mouse skin infection model, and bacterial survival and neutrophil lysis after phagocytosis in vitro was similar between these strains. Comparison of the cytolytic capacity of culture supernatants from wild-type and isogenic deletion strains lacking hlgABC, lukS/F-PV (encoding PVL, and/or lukDE revealed functional redundancy among two-component leukotoxins in vitro. These findings, along with a requirement of specific growth conditions for leukotoxin expression, may explain the apparent limited contribution of any single two-component leukotoxin to USA300 immune evasion and virulence.

  1. Response of methicillin-resistant Staphylococcus aureus to amicoumacin A.

    Directory of Open Access Journals (Sweden)

    Amrita Lama

    Full Text Available Amicoumacin A exhibits strong antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA, hence we sought to uncover its mechanism of action. Genome-wide transcriptome analysis of S. aureus COL in response to amicoumacin A showed alteration in transcription of genes specifying several cellular processes including cell envelope turnover, cross-membrane transport, virulence, metabolism, and general stress response. The most highly induced gene was lrgA, encoding an antiholin-like product, which is induced in cells undergoing a collapse of Δψ. Consistent with the notion that LrgA modulates murein hydrolase activity, COL grown in the presence of amicoumacin A showed reduced autolysis, which was primarily caused by lower hydrolase activity. To gain further insight into the mechanism of action of amicoumacin A, a whole genome comparison of wild-type COL and amicoumacin A-resistant mutants isolated by a serial passage method was carried out. Single point mutations generating codon substitutions were uncovered in ksgA (encoding RNA dimethyltransferase, fusA (elongation factor G, dnaG (primase, lacD (tagatose 1,6-bisphosphate aldolase, and SACOL0611 (a putative glycosyl transferase. The codon substitutions in EF-G that cause amicoumacin A resistance and fusidic acid resistance reside in separate domains and do not bring about cross resistance. Taken together, these results suggest that amicoumacin A might cause perturbation of the cell membrane and lead to energy dissipation. Decreased rates of cellular metabolism including protein synthesis and DNA replication in resistant strains might allow cells to compensate for membrane dysfunction and thus increase cell survivability.

  2. Paediatric Staphylococcus aureus bacteraemia: A single-centre retrospective cohort.

    Science.gov (United States)

    Roediger, Jessica C; Outhred, Alexander C; Shadbolt, Bruce; Britton, Philip N

    2017-02-01

    We aimed to describe the clinical epidemiology of Staphylococcus aureus bacteraemia (SAB) at a large, tertiary/quaternary children's hospital in Australia. We performed a retrospective chart review of SAB cases at the Children's Hospital at Westmead (CHW) over 5 years; 2006-2011. We compared frequency, clinical profile and outcomes of SAB with published data from CHW; 1994-1998. We compared health-care associated with community-associated (HCA-SAB and CA-SAB; defined epidemiologically) and methicillin-resistant with methicillin susceptible S. aureus (MRSA and MSSA). We identified 174 episodes of paediatric SAB with an average annual admission rate of 1.3/1000 which has not increased compared with a decade earlier. Half of the cases (49%) were CA-SAB; 18% were MRSA. The proportion of CA-MRSA bacteraemia (22%) has increased. The proportion of SAB associated with central venous access devices (CVADs; 40%) has increased. CA-SAB cases were more likely to present with a tissue focus of disease (e.g. osteo-articular, pneumonia) and often required surgery. HCA-SAB less frequently required surgery, a minority is MRSA, and vascular device intervention (removal, sterilisation) is common. Six cases (4%) of infective endocarditis (IE) were identified; three with a history of congenital heart disease, two with CVADs in situ. There were no deaths in this cohort. Over an 18-year period, the proportion of SAB due to CA-MRSA and SAB associated with CVADs has increased. Categorisation of SAB as HCA and CA reveals two broad phenotypes of paediatric SAB. SAB in children is infrequently associated with IE. The health-care burden of paediatric SAB is considerable', but mortality is low. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  3. Action of disinfectant quaternary ammonium compounds against Staphylococcus aureus.

    Science.gov (United States)

    Ioannou, Christopher J; Hanlon, Geoff W; Denyer, Stephen P

    2007-01-01

    Mode-of-action studies concluded that alkyldimethylbenzylammonium chloride (ADBAC) (a blend of C(12), C(14) and C(16) alkyl homologues) and didecyldimethylammonium chloride (DDAC) are both membrane-active agents, possessing subtly different modes of action reflecting early cell interactions against Staphylococcus aureus. ADBAC and DDAC exhibited similar MIC behaviors from 0.4 ppm to 1.8 ppm over an inoculum range of 1 x 10(5) to 1 x 10(9) CFU/ml at 35 degrees C. For ADBAC and DDAC, an increased rapidity of killing against S. aureus (final concentration, 2 x 10(9) CFU/ml) was observed at 35 degrees C compared to 25 degrees C. Concentration exponents (eta) for killing were <2.5 for both agents, and temperature influenced the eta value. Examination of leakage and kill data suggested that a single leakage marker was not indicative of cell death. ADBAC and DDAC possessed Langmuir (L4) and high-affinity (H3/4) uptake isotherms, respectively. ADBAC molecules formed a single monolayer of coverage of cells at the end of primary uptake, and DDAC formed a double monolayer. Rapid cell leakage occurred at bactericidal concentrations, with total depletion of the intracellular potassium and 260-nm-absorbing pools released in this strict order. Autolysis was observed for ADBAC and DDAC at concentrations of 9 mug/ml (0.0278 mM and 0.0276 mM, respectively) and above, together with the depletion of approximately 30% of the internal potassium pool. Autolysis contributed to ADBAC and DDAC lethality, although high biocide concentrations may have inhibited autolytic enzyme activity.

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

    DEFF Research Database (Denmark)

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

    2007-01-01

    In Copenhagen, methicillin-resistant Staphylococcus aureus (MRSA) accounted for ... 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...

  5. Sigma Factor SigB Is Crucial to Mediate Staphylococcus aureus Adaptation during Chronic Infections.

    Directory of Open Access Journals (Sweden)

    Lorena Tuchscherr

    2015-04-01

    Full Text Available Staphylococcus aureus is a major human pathogen that causes a range of infections from acute invasive to chronic and difficult-to-treat. Infection strategies associated with persisting S. aureus infections are bacterial host cell invasion and the bacterial ability to dynamically change phenotypes from the aggressive wild-type to small colony variants (SCVs, which are adapted for intracellular long-term persistence. The underlying mechanisms of the bacterial switching and adaptation mechanisms appear to be very dynamic, but are largely unknown. Here, we analyzed the role and the crosstalk of the global S. aureus regulators agr, sarA and SigB by generating single, double and triple mutants, and testing them with proteome analysis and in different in vitro and in vivo infection models. We were able to demonstrate that SigB is the crucial factor for adaptation in chronic infections. During acute infection, the bacteria require the simultaneous action of the agr and sarA loci to defend against invading immune cells by causing inflammation and cytotoxicity and to escape from phagosomes in their host cells that enable them to settle an infection at high bacterial density. To persist intracellularly the bacteria subsequently need to silence agr and sarA. Indeed agr and sarA deletion mutants expressed a much lower number of virulence factors and could persist at high numbers intracellularly. SigB plays a crucial function to promote bacterial intracellular persistence. In fact, ΔsigB-mutants did not generate SCVs and were completely cleared by the host cells within a few days. In this study we identified SigB as an essential factor that enables the bacteria to switch from the highly aggressive phenotype that settles an acute infection to a silent SCV-phenotype that allows for long-term intracellular persistence. Consequently, the SigB-operon represents a possible target to develop preventive and therapeutic strategies against chronic and therapy

  6. Amino Acid Catabolism in Staphylococcus aureus and the Function of Carbon Catabolite Repression

    Directory of Open Access Journals (Sweden)

    Cortney R. Halsey

    2017-02-01

    Full Text Available Staphylococcus aureus must rapidly adapt to a variety of carbon and nitrogen sources during invasion of a host. Within a staphylococcal abscess, preferred carbon sources such as glucose are limiting, suggesting that S. aureus survives through the catabolism of secondary carbon sources. S. aureus encodes pathways to catabolize multiple amino acids, including those that generate pyruvate, 2-oxoglutarate, and oxaloacetate. To assess amino acid catabolism, S. aureus JE2 and mutants were grown in complete defined medium containing 18 amino acids but lacking glucose (CDM. A mutation in the gudB gene, coding for glutamate dehydrogenase, which generates 2-oxoglutarate from glutamate, significantly reduced growth in CDM, suggesting that glutamate and those amino acids generating glutamate, particularly proline, serve as the major carbon source in this medium. Nuclear magnetic resonance (NMR studies confirmed this supposition. Furthermore, a mutation in the ackA gene, coding for acetate kinase, also abrogated growth of JE2 in CDM, suggesting that ATP production from pyruvate-producing amino acids is also critical for growth. In addition, although a functional respiratory chain was absolutely required for growth, the oxygen consumption rate and intracellular ATP concentration were significantly lower during growth in CDM than during growth in glucose-containing media. Finally, transcriptional analyses demonstrated that expression levels of genes coding for the enzymes that synthesize glutamate from proline, arginine, and histidine are repressed by CcpA and carbon catabolite repression. These data show that pathways important for glutamate catabolism or ATP generation via Pta/AckA are important for growth in niches where glucose is not abundant, such as abscesses within skin and soft tissue infections.

  7. Differential induction of innate defense antimicrobial peptides in primary nasal epithelial cells upon stimulation with inflammatory cytokines, Th17 cytokines or bacterial conditioned medium from Staphylococcus aureus isolates.

    Science.gov (United States)

    Burgey, Christine; Kern, Winfried V; Römer, Winfried; Rieg, Siegbert

    2016-01-01

    To date it is incompletely understood why half of the human population is intrinsically resistant to Staphylococcus aureus colonization whereas the other half is intermittently or permanently colonized. Nasal colonization represents the primary niche for S. aureus. We therefore investigated whether primary nasal epithelial cells (HNEC) express antimicrobial peptides (AMPs) upon stimulation by inflammatory cytokines or bacterial conditioned medium (BCM) of different colonizing and invasive staphylococci. Stimulation with classical cytokines (IL-1β, TNF-α, IFN-γ) potently induced hBD-3 and RNase7 in HNEC. Th17 cytokines (IL-17A, IL-17F, IL-22) yielded comparably weak hBD-3 and RNase7 induction and no synergistic effects with classical cytokines. BCM of S. aureus and Staphylococcus epidermidis isolates moderately induced hBD3 and RNase7 mRNA expression without significant differences when comparing colonizing vs. invasive isolates. Our results indicate that HNEC contribute to the innate defense by secretion of an AMP-containing chemical defense shield along the nasal mucosa i.e. within the primary colonization niche of S. aureus. Further studies are needed to investigate whether a deficient AMP expression in the nasal mucosa may be related to different S. aureus carrier states. AMPs or AMP-inducing agents may be promising candidates for future topical decolonization regimens that aim to prevent invasive S. aureus infections. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Genotypic characterisation of Staphylococcus aureus isolates causing bacteraemia at Tygerberg hospital, western cape province, South Africa

    NARCIS (Netherlands)

    Orth, H.; Salaam-Dreyer, Z.; Makgotlho, E.; Sinha, B.; Wasserman, E.

    2011-01-01

    Objectives: There is a paucity of studies on the genotypic characterisation of invasive S. aureus strains and the incidence of communityacquired methicillin resistant S. aureus (CA-MRSA) infections in South Africa. In this study we characterized S. aureus isolates from bacteraemia episodes using

  9. Effect of temperature on antibacterial activity of lidocaine to Staphylococcus aureus and Pseudomonas aeruginosa.

    Science.gov (United States)

    Taki, Y; Seki, K; Ikigai, H; Nishihara, S; Ueno, H; Murota, K; Masuda, S

    1988-01-01

    The effect of temperature on the antibacterial activity of lidocaine to Staphylococcus aureus and Pseudomonas aeruginosa was investigated in vitro. At 10 C at which S. aureus organisms do not grow and might be metabolically inactive, the antibacterial activity of lidocaine to S. aureus was not observed in a concentration of 1%, which was quite antibacterial to S. aureus at 37 C. On the other hand, at 40 C a conspicuously increased antibacterial activity to S. aureus of lidocaine was observed in a concentration of 0.25% which was not antibacterial to S. aureus organisms at 37 C. Similar results were obtained when P. aeruginosa organisms were examined in place of S. aureus, although P. aeruginosa was found to be less susceptible to lidocaine than S. aureus. The clinical significance of the thermal effect on the antibacterial activity of lidocaine was discussed in brief.

  10. The combination of osthole with baicalin protects mice from Staphylococcus aureus pneumonia.

    Science.gov (United States)

    Liu, Shui; Liu, Bowen; Luo, Zhao-Qing; Qiu, Jiaming; Zhou, Xuan; Li, Gen; Zhang, Bing; Deng, Xuming; Yang, Zhenguo; Wang, Jianfeng

    2017-01-01

    We reported the inhibition of α-Hemolysin (Hla) production in methicillin-resistant Staphylococcus aureus USA300 by osthole and further investigated the combination of osthole and baicalin in the treatment of staphylococcal pneumonia. Using cytotoxicity assays and a mouse model of intranasal lung infection, we evaluated the effect of combined therapy. Our results suggest that the combination of osthole and baicalin alleviated S. aureus-mediated A549 cell injury and protected mice from S. aureus pneumonia.

  11. Epidemiology of Streptococcus pneumoniae and Staphylococcus aureus colonization in healthy Venezuelan children

    OpenAIRE

    Quintero, B.; Araque, M.; van der Gaast-de Jongh, C.; Escalona, F.; Correa, M.; Morillo-Puente, S.; Vielma, S.; Hermans, P. W. M.

    2010-01-01

    Streptococcus pneumoniae and Staphylococcus aureus cause significant morbidity and mortality worldwide. We investigated both the colonization and co-colonization characteristics for these pathogens among 250 healthy children from 2 to 5?years of age in Merida, Venezuela, in 2007. The prevalence of S. pneumoniae colonization, S. aureus colonization, and S. pneumoniae?S. aureus co-colonization was 28%, 56%, and 16%, respectively. Pneumococcal serotypes 6B (14%), 19F (12%), 23F (12%), 15 (9%), 6...

  12. Application of molecular techniques in the study of Staphylococcus aureus clonal evolution - A Review

    Directory of Open Access Journals (Sweden)

    Adriana Marcos Vivoni

    2005-11-01

    Full Text Available Staphylococcus aureus is an important agent of healthcare-associated and community-acquired infections. A major characteristic of this microorganism is the ability to develop resistance to antimicrobial agents. Several molecular techniques have been applied for the characterization of S. aureus in epidemiological studies. In the present review, we discuss the application of molecular techniques for typing S. aureus strains and describe the nomenclature and evolution of epidemic clones of this important pathogen.

  13. Hospitalizations and Deaths Caused by Methicillin-Resistant Staphylococcus aureus, United States, 1999?2005

    OpenAIRE

    Klein, Eili; Smith, David L.; Laxminarayan, Ramanan

    2007-01-01

    Hospital-acquired infections with Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA) infections, are a major cause of illness and death and impose serious economic costs on patients and hospitals. However, the recent magnitude and trend of these infections have not been reported. We used national hospitalization and resistance data to estimate the annual number of hospitalizations and deaths associated with S. aureus and MRSA from 1999 through 2005. During this period, t...

  14. Myricetin protects Galleria mellonella against Staphylococcus aureus infection and inhibits multiple virulence factors

    DEFF Research Database (Denmark)

    Nogueira-Silva, L; Da Hora, G. C.A.; Soares, Goncalo Teofilo Afonso Pinheiro

    2017-01-01

    Staphylococcus aureus is an opportunistic pathogen related to a variety of life-threatening infections but for which antimicrobial resistance is liming the treatment options. We report here that myricetin, but not its glycosylated form, can remarkably decrease the production of several S. aureus ...... in the Galleria mellonella model. The present findings reveal the potential of Myr as an alternative multi-target antivirulence candidate to control S. aureus pathogenicity....

  15. Staphylococcus aureus-induced G2/M phase transition delay in host epithelial cells increases bacterial infective efficiency.

    Directory of Open Access Journals (Sweden)

    Ludmila Alekseeva

    Full Text Available Staphylococcus aureus is a highly versatile, opportunistic pathogen and the etiological agent of a wide range of infections in humans and warm-blooded animals. The epithelial surface is its principal site of colonization and infection. In this work, we investigated the cytopathic effect of S. aureus strains from human and animal origins and their ability to affect the host cell cycle in human HeLa and bovine MAC-T epithelial cell lines. S. aureus invasion slowed down cell proliferation and induced a cytopathic effect, resulting in the enlargement of host cells. A dramatic decrease in the number of mitotic cells was observed in the infected cultures. Flow cytometry analysis revealed an S. aureus-induced delay in the G2/M phase transition in synchronous HeLa cells. This delay required the presence of live S. aureus since the addition of the heat-killed bacteria did not alter the cell cycle. The results of Western blot experiments showed that the G2/M transition delay was associated with the accumulation of inactive cyclin-dependent kinase Cdk1, a key inducer of mitosis entry, and with the accumulation of unphosphorylated histone H3, which was correlated with a reduction of the mitotic cell number. Analysis of S. aureus proliferation in asynchronous, G1- and G2-phase-enriched HeLa cells showed that the G2 phase was preferential for bacterial infective efficiency, suggesting that the G2 phase delay may be used by S. aureus for propagation within the host. Taken together, our results divulge the potential of S. aureus in the subversion of key cellular processes such as cell cycle progression, and shed light on the biological significance of S. aureus-induced host cell cycle alteration.

  16. Pathophysiological mechanisms of Staphylococcus non-aureus bone and joint infection: interspecies homogeneity and specific behaviour of S. pseudintermedius

    Directory of Open Access Journals (Sweden)

    Yousef Maali

    2016-07-01

    Full Text Available Implicated in more than 60% of bone and joint infections (BJIs, Staphylococci have a particular tropism for osteoarticular tissue and lead to difficult-to-treat clinical infections. To date, Staphylococcus aureus internalization in non-professional phagocytic cells (NPPCs is a well-explored virulence mechanism involved in BJI chronicity. Conversely, the pathophysiological pathways associated with Staphylococcus non-aureus (SNA BJIs have scarcely been studied despite their high prevalence. In this study, fifteen reference strains from 15 different SNA species were compared in terms of (i adhesion to human fibronectin based on adhesion microplate assays and (ii internalization ability, intracellular persistence and cytotoxicity based on an in vitro infection model using human osteoblasts. Compared to S. aureus, Staphylococcus pseudintermedius was the only species that significantly adhered to human fibronectin. This species was also associated with high (even superior to S. aureus internalization ability, intracellular persistence and cytotoxicity. These findings were confirmed using a panel of 17 different S. pseudintermedius isolates. Additionally, S. pseudintermedius internalization by osteoblasts was completely abolished in β1 integrin-deficient murine osteoblasts. These results suggest the involvement of β1 integrin in the invasion process, although this mechanism was previously restricted to S. aureus. In summary, our results suggest that internalization into NPPCs is not a classical pathophysiologic mechanism of SNA BJIs. S. pseudintermedius appears to be an exception, and its ability to invade and subsequently induce cytotoxicity in NPPCs could explain its severe and necrotic forms of infection, notably in dogs, which exhibit a high prevalence of S. pseudintermedius infection.

  17. Transmission dynamics of methicillin-resistant Staphylococcus aureus in pigs

    Directory of Open Access Journals (Sweden)

    Florence eCrombé

    2013-03-01

    Full Text Available From the mid-2000s on, numerous studies have shown that methicillin-resistant Staphylococcus aureus (MRSA, renowned as human pathogen, has a reservoir in pigs and other livestock. In Europe and North America, clonal complex (CC 398 appears to be the predominant lineage involved. Especially worrisome is its capacity to contaminate humans in close contact with affected animals. Indeed, the typical multi-resistant phenotype of MRSA CC398 and its observed ability of easily acquiring genetic material suggests that MRSA CC398 strains with an increased virulence potential may emerge, for which few therapeutic options would remain. This questions the need to implement interventions to control the presence and spread of MRSA CC398 among pigs. MRSA CC398 shows a high but not fully understood transmission potential in the pig population and is able to persist within that population. Although direct contact is probably the main route for MRSA transmission between pigs, also environmental contamination, the presence of other livestock, the herd size and farm management are factors that may be involved in the dissemination of MRSA CC398. The current review aims at summarizing the research that has so far been done on the transmission dynamics and risk factors for introduction and persistence of MRSA CC398 in farms.

  18. Methicillin-resistant Staphylococcus aureus transmission: unrecognised patient MRSA carriage.

    Science.gov (United States)

    Andersen, Leif Percival; Nielsen, Xiaohui

    2015-04-01

    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. In this study, we describe four cases of nosocomial transmission of MRSA in a hospital with a low MRSA incidence. In one case, a multi-traumatic patient arrived from a hospital in a foreign country and the primary surveillance swaps were negative for MRSA. The second case was a child with burn wounds who was referred from a Danish hospital. The third case was a multi-traumatic patient from Denmark. The fourth case was a new-born child in the neonate unit. In none of the cases, the index patient was known to have MRSA on admission and no specific precautions were taken to prevent transmission. In all cases there was intensive contact between the patient and the staff which may 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 transmission of MRSA, no further transmissions were observed. not relevant. The data in this study are included in the routine surveillance of MRSA at Rigshospitalet and do not form part of a trial.

  19. Blue Light Phototherapy Kills Methycillin Resistant Staphylococcus Aureus (MRSA)

    Science.gov (United States)

    Enwemeka, Chukuka S.; Williams, Debora; Enwemeka, Sombiri K.; Hollosi, Steve; Yens, David

    2010-05-01

    Background: Methycillin resistant staphylococcus aureus (MRSA) bacteria continue to defy most available antibiotics. As a result infections with MRSA remain a growing public health concern. As a paradigm shift and a significant departure from the on-going trend to develop stronger drug-based therapies, we studied the effect of 405 nm and 470 nm wavelengths of blue light on two strains of MRSA—US-300 strain of CA-MRSA and the IS853 strain of HA-MRSA—in vitro. Methods: We cultured and plated each strain, following which bacteria colonies were irradiated with 0, 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 25, 30, 35, 40, 45, 50, 55, or 60 Jcm-2 energy densities—just once. Specimens were incubated at 35° C for 24 h. Then, digital images obtained were quantified to obtain colony counts and the aggregate area occupied by bacteria colonies. Results: Each wavelength produced a statistically significant dose-dependent reduction in both the number and the aggregate area of colonies formed by each bacteria strain (Peffect was non-linear as increases of energy densities between 1.0 and 15 J cm-2 resulted in more bacteria death than similar increases between 15 J cm-2 and 60 J cm-2. Conclusion: At low doses, blue light photo-destroys HA-MRSA and CA-MRSA in vitro; raising the prospect that phototherapy may be an effective clinical tool in the on-going effort to stem MRSA infections.

  20. New pharmacological treatments for methicillin-resistant Staphylococcus aureus infections.

    Science.gov (United States)

    Burke, Stuart L; Rose, Warren E

    2014-03-01

    Despite available treatment options for methicillin-resistant Staphylococcus aureus (MRSA), the morbidity and mortality attributed to the diverse infection manifestations of this pathogen remain high. More anti-MRSA agents are needed as options for treatment of these infections. Ideally, these new agents would be rapidly bactericidal for bloodstream clearance in septic patients, have few toxicities, be active against MRSA in biofilms, be easy to administer, and have oral bioavailability. This review focuses on MRSA agents in Phase III trials or antibiotics currently in the market, which are being studied for new indications. For each agent, the antimicrobial potency against MRSA, pharmacokinetic and pharmacodynamic considerations and approved and potential new indications are presented. The role of novel combination therapies is also introduced. The new lipoglycopeptides oritavancin, telavancin and dalbavancin have the potential to make a large impact on the treatment of MRSA due to unique pharmacokinetic/pharmacodynamic properties and proposed dosing regimens. Other new agents (omadacycline and tedizolid) as well as revisited older agents (fosfomycin and fusidic acid) appear promising but require further study for their potential role. Combination therapy may improve outcomes in patients with high MRSA infection burden or when patient or pathogen factors predict a worse outcome with monotherapy.