9 Acquired inhibitors

摘要: Summary Factor VIII auto-antibody inhibitors, though rare, may present significant and often life-threatening haemorrhage. These auto-antibodies, arising predominantly in older individuals, occur association with autoimmune disorders, lymphoproliferative solid tumours, medications the postpartum state. Almost half of patients develop auto-antibodies spontaneously without an underlying medical condition. inhibitors are characterized as polyclonal IgG immunoglobulins directed against FVIII procoagulant activity. Laboratory diagnosis is made by performing aPTT clotting time conjunction a mixing study, subsequently specific factor assays. Auto-antibodies quantified most commonly utilizing Bethesda assay. Acquired to other coagulation factors, including factors IX, XI, XIII, vWF protein, vitamin K-dependent proteins extremely rare. The principles therapy similar those which apply management auto-antibodies. Treatment acquired varies depending upon condition, titre inhibitor, clinical presentation. Acutely bleeding high-titre generally respond well infusions porcine concentrate, PCCs or rFVIIa. Extracorporeal plasmapheresis exchange will acutely reduce circulating antibodies can be used and/or IgIV. Haemorrhage patient low usually high doses human concentrate. DDAVP also increase levels low-titre inhibitors. Long-term reduction achieved immuno-suppressive regimens using steroids cytotoxic agents, IgIV interferon-alpha. selection appropriate treatment depends associated likelihood spontaneous remission, risk toxicities cost. Determining efficacy safety new modalities for require multicentre randomized trials.