Four patients with acute abdominal complications of systemic lupus erythematosus requiring laparotomy are presented. The complications consisted of intestinal ischaemia, without perforation, in 3 patients and omental infarction in the fourth. In 2 patients the abdominal emergency was the first manifestation of the collagen disease. Tissue removed from 3 patients showed a marked vasculitis on histological examination. The pathogenesis and management of acute abdominal complications of systemic lupus erythematosus are discussed and the literature reviewed.