A long-term follow-up study in essential cryoglobulinemia.
In a case series of 56 patients with essential cryoglobulinemia, 35 were followed-up for 4-13 years (mean 7 years). A membranous proliferative glomerulonephritis, which in about half the cases showed a progression to renal insufficiency, was the commonest complication, observed in more than one third of the patients. In 2 patients hepatic cirrhosis became manifest after a completely asymptomatic period and in 2 others a lymphoproliferative disease appeared 2 and 8 years after the onset of purpura. In 51% of patients the intial clinical pattern did not change. In searching for a correlation between the development of nephropathy and cryoglobulin characteristics, none was demonstrated studying the cryoglobulin level, the presence of autoantibody and the complement components.