Seven patients with systemic lupus erythematosus (SLE) or SLE-like disease developed thrombotic microangiopathy. Prominent features of their acute illnesses were microangiopathic hemolytic anemia (7), thrombocytopenia (7), fever (1), nervous system disease (4), and renal dysfunction (5). Laboratory data were significant for antinuclear antibody (ANA) (7), DNA (5), low C3 level (3), low C4 level (2), antiphospholipid antibody (6), schistocytes (7), and lactate dehydrogenase > 500 (7). All seven patients received treatment that initially included steroids but later included cyclophosphamide (4), plasma infusion (1), plasmapheresis (5), intravenous gamma-globulin (2), anti-platelet agents (2), or vincristine (3). Six patients improved, and one patient expired during treatment. Of the six patients who survived this complication, three expired within the year following their acute illnesses. Histology, available in two cases, showed vascular changes consistent with a microangiopathic process. We conclude that the spectrum of vascular diseases in SLE extends beyond vasculitis to include noninflammatory vascular processes that can cause equally devastating complications.