Acute scleroderma in stable mixed connective tissue disease: treatment by plasmapheresis.

This report describes a case of stable mixed connective tissue disease (MCTD) with development of acute scleroderma with hypertension, oliguric renal failure, microangiopathic hemolytic anemia, and pulmonary infiltrates. The renal histology in the acute episode was that of scleroderma with intimal sclerosis and 'onion skinning' of vessels and glomerular ischemic injury but with no evidence of damage by immune complexes either histologically or by immunofluorescence. improvement occurred after treatment with plasmapheresis, cyclophosphamide, and captopril with return of near normal renal function.