History and clinical findings: For 2 years a 52-year-old man had repeated bouts of purpura, arthralgia and fever. He was known to have abnormal monoclonal gammaglobulins, type IgG-lambda and vasculitis when he had another bout with acute renal failure and necrotizing ulcers in the legs.
Tests: Several laboratory tests were abnormal: erythrocyte sedimentation rate (122 mm), haemoglobin level (9.1 g/dl), white cell count (32,000/microliters), platelet count (562,000/microliters), creatinine level (4.1 mg/dl) and liver enzyme activities. He also had proteinuria (4.5 g daily) and nephritic urinary sediments. The immunoglobulin was subtype IgG3, and a cryoglobulinaemia was also present. Total complement level (CH 50) was not measurable. Bone marrow aspirate revealed plasmocytoma infiltration, and renal biopsy demonstrated necrotizing arteritis, as well as granular subendothelial deposits of IgG and complement.
Treatment and course: After three plasma separations and initiation of the first treatment cycle with a four-day infusion of vincristine, doxorubicin and dexamethasone the creatinine concentration fell to within the normal range and the necroses healed slowly. No cryoglobulin activity has been demonstrable over the past 24 months.