Background: Chronic hepatitis C virus (HCV) infection is associated with a variety of extrahepatic disorders that may relate to direct or indirect effects of virus infection. Increased levels of soluble forms of tumor necrosis factor (TNF) receptors I and II, found in lymphoproliferative and infectious diseases, can interfere with TNF induced apoptotic cell death. The aim of the present study was to evaluate soluble TNF family receptors levels in lymphoproliferative disorders associated with HCV infection.
Methods: One hundred and forty-nine subjects were studied, including 120 anti-HCV positive patients (60 without lymphoproliferative manifestations, 47 with type II cryoglobulinemia and 13 with low-grade B-cell non-Hodgkin's lymphoma (B-NHL)) and 29 anti-HCV negative subjects (19 with low-grade B-NHLs and ten normal controls).
Results: Soluble forms of TNF receptor I, TNF receptor II and Fas were significantly higher in HCV positive patients compared with normal controls. The highest levels were found in patients affected by type II cryoglobulinemia or HCV positive lymphoplasmacytoid lymphomas (LP-NHLs), while HCV positive patients without type II cryoglobulinemia or with other B-NHLs had lower values (P < 0.01).
Conclusions: Among HCV infected individuals, very high levels of soluble TNF receptors are significantly associated with type II cryoglobulinemia and LP-NHLs, suggesting that they may be involved in these proliferative disorders.