The aim of this study was to analyze the clinical impact of hepatitis C virus (HCV)-related cryoglobulinemia in patients that had received liver transplants after HCV cirrhosis. Thirty patients who had received transplants between 1990 and 1996 for HCV cirrhosis and who had a follow-up longer than 1 year were studied. Serum HCV RNA levels, HCV genotype, cryoglobulinemia, rheumatoid factor, serum C3 and C4, IgA, IgG, IgM levels, liver tests, and liver histology were studied 30 +/- 16 months post-transplant. Cryoglobulinemia was found in 9 of 30 patients (30.0%) and was symptomatic in 4 of the 9 cases (glomerulonephritis, 1 case; palpable purpura, 3 cases). Age, sex distribution, alanine aminotransferase (ALAT) activity, and Knodell score did not differ, whether cryoglobulinemia was present or not. Rheumatoid factor (209.5 +/- 70.4 IU/l vs 12.0 +/- 4.4 IU/l, P = 0.004) and IgM levels (3.2 +/- 0.5 g/l vs 1.6 +/- 0.9 g/l, P = 0.0001) were significantly higher, and C4 levels (0.16 +/- 0.16 g/l vs 0.30 +/- 0.10 g/l, P = 0.009) were significantly lower in patients with cryoglobulinemia. One patient died from cryoglobulin-related renal failure. We concluded that, after liver transplantation (LT) for HCV cirrhosis, cryoglobulinemia was frequent and often symptomatic. Cryoglobulinemia did not seem to be associated with more severe graft damage. Cryoglobulinemia-associated morbidity must be taken into account in the management of post-transplant HCV infection.