Postpartum inhibitor to factor VIII: treatment with high-dose immunoglobulin and dexamethasone

Spontaneous occurrence of an acquired inhibitor to factor VIII (FVIII) is a rare event. About 50% of cases are idiopathic. Among younger people, inhib itors are often found in the postpartum period. Treatment must be administe red either to overcome haemorrhagic symptoms or to eradicate the inhibitor. Several approaches have been proposed for inhibitor eradication, based on immunosuppressive drugs such as corticosteroids, cyclophosphamide and azath ioprine, with varying results. High-dose immunoglobulin (HDIg) has been rec ently proposed as first-line therapy. We report on four cases with acquired inhibitor to FVIII occurring 4-8 months after delivery. At diagnosis, inhi bitor titre was < 5 Bethesda units mL(-1) (BU mL(-1)) in three cases, and > 5 BU mL(-1) in one. Factor VIII coagulant activity (FVIII:C) was < 1 U dL( -1) in three cases and 12 U dL(-1) in one. We treated the patients with HDI g (400 mg kg(-1) day(-1) for 5 consecutive days) and dexamethasone (24 mg d ay(-1) for 5-7 consecutive days), administered at the same time. In three w omen, the inhibitor was suppressed in 2-50 weeks. After an off-therapy peri od ranging from 20 to 104 weeks, the FVIII:C was persistently normal and th e inhibitor undetectable. The fourth woman remained unresponsive. In two ca ses, recombinant activated factor VII administration stopped the bleeding. Thus, intermediate- to high-dose dexamethasone and HDIg given at the same t ime could be a successful and safe therapeutic approach for a rapid and com plete remission from the development of FVIII inhibitors.