Fibrinogen osaka IV: A congenital dysfibrinogenemia found in a patient originally reported in relation to surgery,now defined to have an Aα arginine-16 to histidine substitution

We discovered a congenital heterozygous dysfibrinogen in a patient and reported this case in relation to surgery some time ago (Jpn J Surg (1988) 18:43–46).³ Further studies on the isolated abnormal population of fibrinogen derived from this patient have revealed that fibrinopeptide A was not cleaved by ancrod, a snake venom-derived thrombin-like enzyme, but by thrombin, slowly but completely. The released fibrinopeptide A components, being the A, AY, and AP peptides, were all found to be abnormal, as evidenced by slightly earlier elution positions on high-performance liquid chromatography, compared with the normal counterparts. By analyzing their amino acid sequence, we have identified an arginine to histidine substitution at position 16 of the A chain, the thrombin cleavage site. Utilizing insolubilized abnormal fibrinogen, we confirmed that the polymerization site assigned to the central E domain, the A site, was exposed by thrombin, but not by ancrod. This dysfibrinogen, designated as fibrinogen Osaka IV, is the second abnormal molecule with an A arginine-16 to histidine substitution identified among Japanese families.     

Role of sialic acid in acquired dysfibrinogenemia associated with liver cirrhosis

Summary The possible existence of acquired dysfibrinogenemia was investigated in blood samples from 30 patients with liver cirrhosis, 15 newborns and 30 healthy control subjects. Alterations of thrombin time were found in newborns and in 14 cirrhotic patients; glucide fraction levels were measured in these subjects and an increase in sialic acid content was observed. Its functional role was studied by comparing thrombin time and electrophoretic mobility of purified and desialylated forms of fibrinogen. We observed a thrombin time normalization, which was initially prolonged upon the removal of the sialic acid. The anodic electrophoretic mobility underwent changes due to the removal of sialic acid.     

Heterozygous protein C deficiency and dysfibrinogenemia acquired by liver transplantation

Orthotopic liver transplantation is now a successful treatment for end-stage liver diseases. Since most components of the coagulation system are synthesized by liver parenchymal cells, there is always a risk of genetic defects of hemostasis being transmitting by liver transplantation. Some coagulation factor defects, such as protein C deficiency, do not induce abnormalities in routine coagulation tests and, thus, go undetected before organ procurement. We report the first case, to our knowledge, of the transmission of heterozygous protein C deficiency, an autosomal recessive genetic defect, associated with dysfibrinogenemia, an autosomal dominant trait, by liver transplantation. Both the recipient and the donor presented with severe thrombotic complications. This case shows that potentially morbid genetic defects can be transmitted by organ transplantation, and it emphasizes the difficulty associated with organ procurement criteria, particularly for liver transplantation, in which routine blood tests appear insufficient for determining whether or not organs can or should be procured from a given donor.     

Intraoperative management of a dysfibrinogenemic patient with gastric cancer

The intraoperative management of a dysfibrinogenemic patient with gastric cancer is reported herein. In order to avoid abnormal bleeding, the fibrinogen level during a cancer-operation should be maintained above 60 mg/dl. Cryoprecipitate, however, is not suitable for fibrinogen supplementation because of its short lifein vivo.     

一个纤维蛋白原γ链Arg275His突变导致的遗传性异常纤维蛋白原血症家系

目的　对一个遗传性异常纤维蛋白原血症家系进行表型和基因型分析。方法　采集家系3代5人外周血,吸取上层血浆用血凝仪检测活化部分凝血酶原时间、凝血酶原时间、凝血酶时间、蛋白C活性、蛋白S活性和抗凝血酶活性,纤维蛋白原活性和抗原分别用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扩增纤维蛋白原基因FGA、FGB和FGG所有外显子及其侧翼序列,PCR产物纯化后直接测序以检测基因突变。结果　先证者活化部分凝血酶原时间、凝血酶原时间正常,凝血酶时间超出正常上限值2倍以上,纤维蛋白原活性明显下降,抗原也低于正常范围,且活性显著低于抗原;其母表型检测结果与之相似。基因分析显示先证者呈纤维蛋白原FGG基因第8外显子g.5 6 78G>A杂合碱基置换,导致Arg2 75 His错义突变,该突变来源于母系。结论　纤维蛋白原γ链Arg2 75 His杂合错义突变是引起该家系异常纤维蛋白原血症的原因。     

Stroke in two young siblings with congenital dysfibrinogenemia

Two young siblings (a male of 21 and his sister of 26 years) suffered from arterial thrombosis episodes of the carotid and abdominal aorta documented by angiographic studies. In the absence of any known predisposing factor in the family and personal history, the laboratory investigation of both patients revealed coagulation abnormalities compatible with a dysfibrinogenemia. The occurrence of a similar defect also in plasma of one of the propositi's asymptomatic relatives is suggestive of an inherited fibrinogen disorder This work was supported by the Italian National Research Council (Clinical Pharmacology and Rare Diseases) and by a grant of the Mario Negri Foundation, New York, N.Y., USA.