Hepatitis C virus genotypes and clinical features in hepatitis C virus-related mixed cryoglobulinemia

Mixed cryoglobulinemia is a systemic disease, almost always associated with hepatitis C virus infection and characterized by purpura and cutaneous vasculitis, asthenia, arthralgias, and often renal and neurological involvement. No significant differences have been described to date in mixed cryoglobulinemia patients with type 1, 2, or 3 hepatitis C virus infection with respect to symptoms, while a higher prevalence of genotype 2a has been reported in patients without clinical and biochemical signs of liver disease or with serum autoantibodies. We examined 33 hepatitis C virus-positive patients with mixed cryoglobulinemia to assess if any clinical or serological feature is related to infection with different genotypes. All subjects underwent viral genotype determination by means of a single-step polymerase chain reaction. Thirteen patients (39%) were infected with hepatitis C virus type 1b, 17 (52%) with type 2a or 2a/c, and 3 (9%) with type 3. There was a significant difference in the frequency of peripheral nervous system involvement: paresthesias or other symptoms of peripheral neuropathy were less frequent in patients with 2a or 2a/c infection (29%) than in patients with type 1b or type 3 infection (88%, P = 0.003). Only patients with hepatitis C virus type 2 had urticaria or cutaneous ulcers. These patients also had a lower frequency of arthralgias, lower cryocrit values (P = 0.02), and lower serum levels of alanine-aminotransferase and gamma-glutamyl-transpeptidase (P < 0.04) than patients with type 1 and type 3 infection. The prevalence of antinuclear antibody positivity was similar in the three groups.