This report discusses the diagnosis and treatment of afibrinogenemia in a Chihuahua. Prolongations of prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin clotting time (TCT) together with fibrinogen assay results of either no or trace amounts of fibrinogen support a diagnosis of afibrinogenemia. Differential diagnoses include common coagulopathies, liver failure, and disseminated intravascular coagulation (DIC). Either aggressive cryoprecipitate or plasma transfusions are required to treat afibrinogenemia. The current guidelines for treatment of coagulopathies include plasma transfusions (either 15-30 mL/kg or until both PT and aPTT are normalized). This report describes a case in which bleeding persisted 2 days after standard plasma transfusion levels were administered and PT and aPTT levels had normalized. In this case, the bleeding was stabilized for up to 2 mo after administering > 54 mL/kg plasma. In human medicine, either cryoprecipitate or fibrinogen concentrate is used to increase blood fibrinogen levels to 100 mg/dL for minor bleeding and 200 mg/dL for major bleeding. Further studies are needed; however, the author of this report suggests that aggressive transfusions and monitoring are needed in veterinary afibrinogenemia cases.
C. F. S. Amaral
Full Text Available This paper reports two cases of afibrinogenemia with normal platelet count following Crotalus durissus terrificus, snake bite Both patients presented high output acute renal failure and case two also had increased blood levels of CPK and LDH compatible with the diagnosis of rhabdomyolysis. Case one was given an unknown amount of antivenom and was treated with epsilonaminocaproic acid and a fresh whole blood transfusion and showed recovery of the coagulation disturbance 40 hours following these measures. Case two was given an adequate amount of crotalide antivenom and the coagulation tests performed 12 hours later showed a normal partial thromboplastin time and fibrinogen 86 mg/100ml. Case one presented no haemorrhagic disturbances. Case two presented persistent bleeding following venopuncture and after removal of impetigo crust in the legs. Acute renal failure was treated conservatively and both patients were discharged from the hospital with recovery of the renal function.
Ozdemir, Mehmet A; Işik, Bilgen; Patiroglu, Turkan; Karakukcu, Musa; Mutlu, Fatma T; Yilmaz, Ebru; Unal, Ekrem
Although congenital afibrinogenemia is a rare autosomal recessive bleeding disorder, it can be more frequently encountered in countries where consanguineous marriages are common. Congenital afibrinogenemia is characterized by the undetectable low level of fibrinogen, which causes hemorrhagic diathesis. Paradoxically, arterial and venous thromboembolic complications can develop in patients with afibrinogenemia, which may cause a diagnostic problem to anyone unfamiliar with its clinical features. We report a case of congenital afibrinogenemia presenting with bilateral ischemic lesions of bilateral foot and ankle that required amputations. The patient was treated with fibrinogen concentrate, low-molecular-weight heparin, aspirin, and nifedipine. In conclusion, arterial and venous thromboembolic complications are rare, but severe complications of afibrinogenemia. The management of thromboembolic complications in patients with afibrinogenemia is a balance game. At one end of the scale, there is a bleeding disorder, and at the other end, there is a thrombosis. This fine adjustment is a job of mastery.
Sham Sunder Goyal
Full Text Available Congenital afibrinogenemia is a very rare autosomal recessive disorder, results from mutation that affects plasma fibrinogen concentration. It is frequently associated with bleeding diathesis of varying severity. We describe the case of a 10-year-old child diagnosed of congenital afibrinogenemia who presented to hospital with subperiosteal haematoma and was posted for incision and drainage. Replacement therapy is the mainstay of treatment of bleeding episodes in this patient and plasma-derived fibrinogen concentrate is the agent of choice. Cryoprecipitate and fresh frozen plasma are alternative treatments. Appropriate amount of cryoprecipitate were transfused pre-operatively to the child. Individuals with congenital afibrinogenemia should be managed by a comprehensive bleeding disorder care team experienced in diagnosing and managing inherited bleeding disorders. Anaesthesiologist, surgeons and haematologist should work like a unit to manage the surgical emergencies.
Sartori, M T; Teresa, S M; Milan, M; Marta, M; de Bon, E; Emiliano, D B; Fadin, M; Mariangela, F; Pesavento, R; Raffaele, P; Zanon, E; Ezio, Z
Thrombotic events in congenital hypo-afibrinogenemia have been rarely reported, either in association or not with replacement therapy or thrombotic risk factors. We describe clinical findings and management of thrombosis of abdominal aorta with peripheral embolism in a patient with congenital afibrinogenemia. A review of arterial thrombosis in inherited hypo-afibrinogenemia was also performed. The patient with a severe bleeding history requiring prophylaxis with fibrinogen concentrates (FC) was admitted for ischaemia of the 4th right toe. An angio-CT of abdominal aorta showed a thrombosis from the origin of renal arteries to the carrefour with a distal floating part. No thrombotic risk factors were found; a previous traumatic lesion of aortic wall might have triggered the thrombus formation, whereas the role of FC prophylaxis remains uncertain. The patient was successfully treated with FC, enoxaparin followed by fondaparinux, and low-dose aspirin without bleeding or thrombosis recurrence. After 2 years, aortic thrombus was almost completely recovered. Sixteen hypo/afibrinogenemia patients with arterial thrombosis were found in Literature, showing that thrombosis often occurs at a young age, involves large vessels, its recurrence is not unusual, and therapeutic strategy is not defined yet. Our therapeutic approach was effective and also safe, but further studies are needed to improve the knowledge of pathogenesis and the anti-thrombotic management in this peculiar setting.
Neerman-Arbez, M; de Moerloose, P; Honsberger, A; Parlier, G; Arnuti, B; Biron, C; Borg, J Y; Eber, S; Meili, E; Peter-Salonen, K; Ripoll, L; Vervel, C; d'Oiron, R; Staeger, P; Antonarakis, S E; Morris, M A
Congenital afibrinogenemia is an autosomal recessive disorder characterized by the complete absence of detectable fibrinogen. We previously identified the first causative mutations for this disease in a non-consanguineous Swiss family. These were homozygous deletions of approximately 11 kb of the fibrinogen alpha chain gene (FGA). Our subsequent study revealed that the majority of cases were attributable to truncating mutations in FGA, with the most common mutation affecting the donor splice site in FGA intron 4 (IVS4+1 G-->T). Here, we report 13 further unrelated patients with mutations in FGA, confirming the relative importance of this gene compared with FGG and FGB in the molecular aetiology of afibrinogenemia. Three other patients were homozygous for mutations in FGG. Eight novel mutations were identified: five in FGA and three in FGG. Sufficient mutation data is now available to permit an effective strategy for the genetic diagnosis of congenital afibrinogenemia.
Levrat, Emmanuel; Aboukhamis, Imad; de Moerloose, Philippe; Farho, Jaafar; Chamaa, Sahar; Reber, Guido; Fort, Alexandre; Neerman-Arbez, Marguerite
Congenital afibrinogenemia is a rare autosomal recessive coagulation disorder characterized essentially by bleeding symptoms, but miscarriages and, paradoxically, thromboembolic events can also occur. Most reported mutations leading to congenital afibrinogenemia are located in FGA encoding the fibrinogen A α-chain. In this study, we analysed 12 individuals from a consanguineous Syrian family with reduced or absent fibrinogen levels: those with fibrinogen levels around 1 g/l (n = 7) were found to be heterozygous for a novel frameshift mutation in FGA exon 5 (c.1846 del A) and those with undetectable fibrinogen levels (n = 5) were homozygous for the same mutation. This novel frameshift mutation is the most C-terminal causative FGA mutation identified to date in afibrinogenemic patients. The resulting aberrant Aα-chain (p.Thr616HisfsX32) is most likely synthesized, but is less efficiently assembled and/or secreted into the circulation given the phenotype of asymptomatic hypofibrinogenemia in heterozygous individuals and bleeding diathesis in homozygous individuals.
Neerman-Arbez, Marguerite; Germanos-Haddad, Myrna; Tzanidakis, Konstantinos; Vu, Dung; Deutsch, Samuel; David, Armelle; Morris, Michael A; de Moerloose, Philippe
Congenital afibrinogenemia, the most severe form of fibrinogen deficiency, is characterized by the complete absence of fibrinogen. The disease is caused by mutations in 1 of the 3 fibrinogen genes FGG, FGA, and FGB, clustered on the long arm of human chromosome 4. The majority of cases are due to null mutations in the FGA gene although one would expect the 3 genes to be equally implicated. However, most patients studied so far are white, and therefore the identification of causative mutations in non-European families is necessary to establish if this finding holds true in all ethnic groups. In this study, we report the identification of a novel nonsense mutation (Arg134Xaa) in the FGG gene responsible for congenital afibrinogenemia in 10 patients from Lebanon. Expression studies in COS-7 cells demonstrated that the Arg134Xaa codon, which is encoded by adjacent exons (TG-intron 4-A) affected neither mRNA splicing nor stability, but led to the production of an unstable, severely truncated fibrinogen gamma chain that is not incorporated into a functional fibrinogen hexamer.
Girolami, A; De Marco, L; Virgolini, L; Peruffo, R; Fabris, F
Platelet adhesiveness and aggregation were studied in three patients with congenital afibrinogenemia. The results obtained may be summarized as follows: The retention of platelets to a glass-bead filter determined with the Salzman method was significantly decreased; it was normal after fibrinogen infusion. With a modification of the Hellem test the values obtained were slightly decreased. Adrenalin-induced aggregation was absent whereas ADP-and collagen-induced aggregation was near normal or slightly decreased. Thrombofax aggregation was absent in citrated plasma. The abnormalities of platelet aggregation were corrected after fibrinogen infusion or after addition in vitro of fibrinogen, hemofilia A plasma and PPP obtained from an afibrinogenemic patient after fibrinogen infusion. The abnormalities of platelet aggregation were corrected well by ADP, collagen and Thrombofax in heparinized blood, but only a slight correction of adrenalin-induced aggregation was noted. Thrombin aggregation proved to be normal with the higher concentrations, whereas it was defective with the lower ones. Ristocetin aggregation was normal in citrated plasma at the concentration of 1.5 mg per ml but it was absent at the lower concentration (1.0 mg per ml). Ristocetin aggregation was, on the other hand absent in heparinized blood regardless of the concentration. These findings are in agreement with the presence of a prolonged bleeding time in congenital afibrinogenemia and suggest that fibrinogen plays an important role in platelet aggregation and adhesiveness.
张剑; 赵小娟; 王兆钺; 余自强; 曹丽娟; 马珍妮; 张杰; 张威; 白霞
Objective To investigate the genetic defect and its mechanism in a patient with congenital afibrinogenemia.Methods The plasma fibrinogen activity and antigen of the patient was determined using the Clauss method and immuno-nephelometric assay,respectively.Genomic DNA was isolated from peripheral blood of the proband and his related family members.All exons and exon-intron boundaries of the three fibrinogen genes (FGA,FGB,FGG) were amplified by PCR followed by direct sequencing.Thrombin fibrin aggregation curve were detected in the plasma of the patient.Wild-type and mutation type fibrinogen vectors were constructed,and then transfected into COS-7 cells.The wild-type and mutant proteins from the culture media and cell lysates were tested by Western blot and ELISA.Results APTT,PT,TT were significantly longer in the proband.Plasma fibrinogen activity and antigen of the patient could not be detected using the Clauss method and immuno-nephelometry,respectively.Gene analysis revealed that a novel homozygous GTTT insertion between nucleotides 2833 and 2834 in FGB exon 2 in the proband.The proband' s father,mother,brother and son were heterozygous.The polymerization curves of the patient did not show a lag phase or final turbidity,compared with the normal controls.Western blot analysis showed the lack of complete half-molecules of the fibrinogen molecule and fibrinogen in patient's plasma under non-reducing conditions.It also could not detect the truncated Bβ chain under reducing conditions.Abnormal fibrinogen molecule (molecule weight ＞340 000) were found in transfected COS-7 cells by Western blot,which indicated that the mutation caused the abnormal intracellular fibrinogen molecule assembly.The fibrinogen band was absent in culture media transfected by the mutation.Fibrinogen levels of mutant fibrinogen were no significant different from those of wild-type fibrinogen in cell lysates by ELISA analysis [(2.47+0.30) μg/ml for (2.65+0.60) μg/ml,P =0.0889] ;However
方怡; 王学锋; 王鸿利; 傅启华; 武文漫; 丁秋兰; 戴菁; 胡翊群; 王振义
目的对一例遗传性无纤维蛋白原血症家系进行基因分析.方法用PCR法对该家系先证者纤维蛋白原基因FGA、FGB和FGG的所有外显子及其侧翼序列进行扩增,PCR产物纯化后直接测序,检测其基因突变.结果先证者呈纤维蛋白原FGA基因g.1892-1899位AGTA/GTAA 4 bp和g.1978-3215位1 238 bp复合杂合缺失.结论纤维蛋白原FGA基因复合杂合缺失是引起该家系先证者无纤维蛋白原血症的原因.
吴淑燕; 王兆钺; 董宁征; 白霞; 阮长耿
目的对1例遗传性无纤维蛋白原血症患者及其家系成员进行基因分析,探讨遗传性无纤维蛋白原血症发病的分子机制.方法凝血酶法与免疫比浊法测定血浆纤维蛋白原(Fg)含量,提取先证者及其家系成员外周血基因组DNA,PCR法扩增其Fg的FGA、FGB和FGG基因所有外显子和侧翼序列,DNA序列分析Fg的基因异常.将先证者突变序列、家系成员和50名正常人相应序列的PCR产物用限制性内切酶Rsa Ⅰ消化,以进一步确定基因突变位点并排除基因多态性.结果用Clauss法检测不到先证者及其父亲的血浆Fg,用免疫比浊法测定时,Fg含量均＜0.02g/L.两人FGA基因外显子4第3108位核苷酸发生C→T纯合性改变,使Fg的Aα链第150位密码子(CAG,编码Gln)突变为终止密码TAG.先证者及其父亲的FGA基因外显子4和侧翼序列的PCR产物,不能被Rsa Ⅰ酶切,其母亲及部分家系成员的PCR产物被部分酶切,而正常人和该家系中的5个成员的PCR产物可被完全酶切.结论FGA基因(外显子4)Q150X无义突变导致该家系先证者及其父亲遗传性无Fg血症,家系中部分成员为携带者,此突变是一种国际上尚未报道的新的突变类型.
徐修才; 周荣富; 吴竞生; 方怡; 王学锋; 翟志敏; 王鸿利
Full Text Available utation of any of fibrinogen genes (FGA, FGB, and FGG) include both quantitative defects (type I deficiencies... or afibrinogenemia) and qualitative defects (type II deficiencies or dysfibrinogenemia). Fibrinogen defici
薛烽; 葛菁; 顾东生; 杜伟廷; 隋涛; 赵海丰; 张磊; 杨仁池
方怡; 王鸿利; 王学锋; 傅启华; 王文斌; 谢爽; 周荣富; 戴菁; 王振义
遗传性无纤维蛋白原血症是一种由于纤维蛋白原基因缺陷所致常染色体隐性遗传病.为了对1例遗传性无纤维蛋白原血症家系进行表型和基因型分析,采集了该家系三代10人外周血,吸取上层血浆用血凝仪检测活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)和凝血酶时间(TI);纤维蛋白原(Fg)含量分别用Clauss法和免疫比浊法进行检测;以常规酚-氯仿法抽提家系所有成员外周血基因组DNA,PCR扩增Fg基因FGA、FGB和FGG所有外显子及其侧翼序列和启动子区,PCR产物纯化后直接测序以检测基因突变.102例健康献血者作为正常对照.结果表明:先证者表型诊断为无纤维蛋白原血症;基因型呈Fg B β-链Arg17stop和Gly347Arg复合杂合突变,前者来源于母系,后者来源于父系.结论:Fg B β-链Arg17 stop和Gly347Arg复合杂合突变是引起该家系先证者产生无纤维蛋白原血症的原因.
Lebreton, Aurélien; Casini, Alessandro
Congenital fibrinogen disorders comprise quantitative disorders defined by a complete absence (afibrinogenemia) or by a decreased level (hypofibrinogenemia) of circulating fibrinogen and qualitative disorders characterized by a discrepancy between the activity and the antigenic levels of fibrinogen (dysfibrinogenemia and hypodysfibrinogenemia). The biological diagnosis is based on a standard haemostasis assessment. All the coagulation tests that depend on the formation of fibrin as the end point are affected; although in dysfibrinogenemia the specificity and sensitivity of routine test depend on reagent and techniques. A genetic exploration permits to confirm the diagnosis and may enhance the prediction of the patient's phenotype. Homozygous or composite heterozygous null mutations are most often responsible for afibrinogenemia while hypofibrinogenemic patients are mainly heterozygous carrier of an afibrinogenemic allele. Heterozygous missense mutations are prevalent in dysfibrinogenemia, with two hot spot localized in exon 2 of the FGA and in the exon 8 of the FGG. The correlation between phenotype and genotype has been identified in some fibrinogen variants, including six mutations clustered in exons 8 and 9 of the FGG leading to hypofibrinogenemia with hepatic inclusions of abnormal fibrinogen aggregates as well as a few mutations associated with an increase risk of thrombotic events. A familial screening and additional functional assays should be carried out when possible.
Andy H Vo
Full Text Available Cessation of bleeding after trauma is a necessary evolutionary vertebrate adaption for survival. One of the major pathways regulating response to hemorrhage is the coagulation cascade, which ends with the cleavage of fibrinogen to form a stable clot. Patients with low or absent fibrinogen are at risk for bleeding. While much detailed information is known about fibrinogen regulation and function through studies of humans and mammalian models, bleeding risk in patients cannot always be accurately predicted purely based on fibrinogen levels, suggesting an influence of modifying factors and a need for additional genetic models. The zebrafish has orthologs to the three components of fibrinogen (fga, fgb, and fgg, but it hasn't yet been shown that zebrafish fibrinogen functions to prevent bleeding in vivo. Here we show that zebrafish fibrinogen is incorporated into an induced thrombus, and deficiency results in hemorrhage. An Fgb-eGFP fusion protein is incorporated into a developing thrombus induced by laser injury, but causes bleeding in adult transgenic fish. Antisense morpholino knockdown results in intracranial and intramuscular hemorrhage at 3 days post fertilization. The observed phenotypes are consistent with symptoms exhibited by patients with hypo- and afibrinogenemia. These data demonstrate that zebrafish possess highly conserved orthologs of the fibrinogen chains, which function similarly to mammals through the formation of a fibrin clot.
Platè, Manuela; Duga, Stefano; Castaman, Giancarlo; Rodeghiero, Francesco; Asselta, Rosanna
Quantitative fibrinogen deficiency is a rare bleeding disorder characterized by abnormally low levels of fibrinogen in plasma, generally due to mutations in one of the three fibrinogen genes: FGA, FGB, and FGG, coding for A alpha, B beta, and gamma chain, respectively. Although the partial defect (hypofibrinogenemia) is due to mutations occurring in the heterozygous state, homozygosity or compound heterozygosity for the same genetic defects give rise to the more severe afibrinogenemia. Mutations responsible for these conditions are scattered throughout the three fibrinogen genes, with only few sites representing relative mutational hot spots. In this study, we report the identification of the FGG IVS6-320A>T mutation in an Italian hypofibrinogenemic patient from Veneto (a region of North-Eastern Italy). This 'deep-intronic' mutation, which would go unnoticed by using conventional mutational screening strategies was previously reported in an afibrinogenemic family from Vicenza (a province of Veneto). The geographic clustering of patients carrying the FGG IVS6-320A>T mutation and the results of haplotype analysis suggest the existence of a common founder. This information will be useful to direct future genetic screenings in patients coming from the same geographic area.
Full Text Available Objective: We did a clinical audit to determine the status of coagulation disorders in a hemophilia care center in Pakistan. Setting: Fatimid foundation blood bank and hematological diseases center, Lahore. Study Design: This is a retrospective descriptive study. Materials and Methods: All patients registered at Lahore center were included. Data was collected using a questionnaire including age, gender, diagnosis, hepatitis and human immune deficiency virus (HIV status, number of episodes of bleeding, most common site of bleeding, severity of disorder and number of transfusions required to treat the episode. Results: During the study period, a total of 923 registered patients were reviewed at Lahore center and of these, 408 patients (44.2% were on regular follow-up. Inherited bleeding disorders identified in these patients included hemophilia A, hemophilia B, vWD, factor VII deficiency, factor V deficiency, factor X deficiency, dysfibrinogenemia, afibrinogenemia, factor XIII deficiency; and platelet function defects. Median age was 17 years with a range of three to 57 years. Median age at diagnosis was one year. There were 329 (80.6% males and 79 (19.3% females. The products used in these patients included factor VIII concentrate, fresh frozen plasma, cryoprecipitate, cryosupernatant and platelets. Testing for transmission of viral infections was also done in these patients and one patient (0.2% was found hepatitis B positive, six patients (1.4% were hepatitis C positive and two patients (0.49% were HIV positive. Conclusion: Hemophilia A, hemophilia B and vWD are the commonly encountered inherited bleeding disorders in our patients followed by other recessively transmitted disorders with a median age of 17 years and male to female ratio of 4: 1. Most of the patients utilized services available at Fatimid foundation with good clinical results. In Pakistan, non-governmental organizations (NGOs are trying their best for providing optimal treatment
, cholesterol embolism, splenic granuloma, congenital diaphragmatic hernia, rib exostosis, pancreatitis, Gaucher's disease, Wilson's disease, pheochromocytoma, afibrinogenemia and ruptured ectopic pregnancy. Conclusions Emergency physicians should be attuned to the fact that rupture of the spleen can occur in the absence of major trauma or previously diagnosed splenic disease. The occurrence of such a rupture is likely to be the manifesting complaint of an underlying disease. Furthermore, colonoscopy should be more widely documented as a cause of splenic rupture.