Severe abdominal vasculitis with hepatitis B antigenemia.

Two cases of necrotizing abdominal vasculitis associated with hepatitis B are reported. The diagnosis of mesenteric vasculitis is often delayed, and intestinal perforation is common. Early recognition of the disease and early treatment with corticosteroid and immunosuppressive drugs may alter the course of the disease. Preoperative diagnosis is best made by mesenteric arteriography and rectal biopsy.