High prevalence of peripheral neuropathy in hepatitis C virus infected patients with symptomatic and asymptomatic cryoglobulinaemia

BACKGROUND: Fifty per cent of patients with chronic hepatitis C, show detectable cryoglobulinaemia, even though most of them do not show cryoglobulinaemia related symptoms. Peripheral neuropathy is present in most of the patients with symptomatic cryoglobulinaemia, where it may be the first clinical manifestation. The prevalence of peripheral neuropathy in patients with hepatitis C and cryoglobulinaemia is unknown. AIMS: To assess the prevalence of peripheral neuropathy in HCV infected patients with symptomatic or asymptomatic detectable cryoglobulinaemia. PATIENTS AND METHODS: Eighty-nine patients with HCV infection and detectable cryoglobulinaemia underwent electrophysiological studies. RESULTS: Electrophysiological evidence of peripheral neuropathy was found in 37% and was significantly associated with: the presence of cryoglobulinaemia syndrome, older age, higher rheumatoid factor reactivity and immunoglobulin M levels and reduced complement C4 activity. However, electrophysiological evidence of peripheral neuropathy was unrelated to cryocrit levels and type of cryoglobulinaemia and was found in 23/68 patients without any symptoms of cryoglobulinaemia other than pain and paresthesia. CONCLUSIONS: These findings suggest that peripheral neuropathy is frequent in patients with hepatitis C and detectable cryoglobulins. Neuropathy was found to be present in 1/3 of patients without other cryoglobulinaemia-related symptoms, thus a direct or indirect role of HCV, independent of cryoglobulinaemia, in the pathogenesis of nerve damage cannot be ruled out.