Nawarawong W, Wyshock E, Meloni F J, Weitz J, Schmaier A H
Department of Medicine, Chiang Mai University, Thailand.
Br J Haematol. 1991 Oct;79(2):296-301. doi: 10.1111/j.1365-2141.1991.tb04536.x.
An asymptomatic 50-year-old male with a gamma globulin paraprotein was found to have prolonged prothrombin time, activated partial thromboplastin time, and thrombin time but a normal reptilase time. The prolonged clotting times were not the result of a factor deficiency because they were not corrected by the addition of normal plasma. Instead, this patient had an antibody that delayed thrombin-mediated fibrinopeptide B release thereby producing an apparent dysfibrinogenaemia. His isolated IgG prolonged the thrombin clotting time of both normal plasma and fibrinogen. Precincubation of his IgG with fibrinopeptide B, but not with fibrinopeptide A or thrombin, decreased its ability to prolong the thrombin clotting time. The patient's purified IgG but not control IgG delayed thrombin-mediated fibrinopeptide B release from fibrinogen without affecting the release of fibrinopeptide A. These studies define a novel, clinically silent dysfibrinogenaemia due to an antibody that delays thrombin-mediated fibrinopeptide B release from fibrinogen thereby markedly prolonging the clotting times.
一名50岁无症状男性，γ球蛋白副蛋白升高，凝血酶原时间、活化部分凝血活酶时间和凝血酶时间延长，但蝰蛇毒时间正常。凝血时间延长并非因子缺乏所致，因为加入正常血浆后未得到纠正。相反，该患者有一种抗体，可延迟凝血酶介导的纤维蛋白肽B释放，从而导致明显的异常纤维蛋白原血症。其分离出的IgG延长了正常血浆和纤维蛋白原的凝血酶凝血时间。将其IgG与纤维蛋白肽B预温育，而非与纤维蛋白肽A或凝血酶预温育，可降低其延长凝血酶凝血时间的能力。患者纯化的IgG而非对照IgG延迟了凝血酶介导的纤维蛋白肽B从纤维蛋白原的释放，而不影响纤维蛋白肽A的释放。这些研究定义了一种新型的、临床上无症状的异常纤维蛋白原血症，其由一种抗体引起，该抗体延迟了凝血酶介导的纤维蛋白肽B从纤维蛋白原的释放，从而显著延长了凝血时间。
