Low 25-hydroxyvitamin D serum levels correlate with the presence of extra-hepatic manifestations in chronic hepatitis C virus infection.

OBJECTIVE Chronic HCV infection is associated with extra-hepatic manifestations. Recent studies have suggested an immunomodulatory role for vitamin D during HCV infection. We investigated the association between serum vitamin D status and the presence of HCV extra-hepatic manifestations. METHODS 25(OH)D serum levels were assessed in 94 HCV(+)RNA(+) patients [including 48 patients with mixed cryoglobulinaemia (MC) vasculitis]. Correlations between serum 25(OH)D levels and the presence of extra-hepatic manifestations of HCV infection were analysed. RESULTS Overall, 84 of 94 patients (89%) had hypovitaminosis D (≤30 ng/ml). Patients with vitamin D deficiency vs insufficiency vs sufficiency more frequently had systemic vasculitis (P = 0.02), in particular purpura (P = 0.006), detectable MC (P = 0.008) and low C4 serum levels (P = 0.006). Serum levels of 25(OH)D were also correlated with cryoglobulin and C4 levels and with marginal zone B cells and regulatory T cells. In multivariate analysis, the presence of MC and systemic vasculitis remained independently associated with low 25(OH)D levels. CONCLUSION In chronic HCV infection, low 25(OH)D levels correlate with the presence of mixed cryoglobulinaemia and systemic vasculitis in chronic HCV infection. These findings suggest the potential multifaceted benefits of vitamin D supplementation in HCV-infected patients with extra-hepatic manifestations, but interventional studies are needed to confirm these data.