Viral hepatitis and proteinuria in an area endemic for hepatitis B and C infections: another chain of link?

Abstract

Virus hepatitis may lead to nephropathy as one of its multiple extrahepatic manifestations. Proteinuria by dipstick, a simple test in practice, is a useful and cardinal sign of underlying renal abnormalities. The aim of this study was to elucidate the impact of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infections on the occurrence of proteinuria amongst adults. A prospective, cross-sectional, community-based study was conducted in an HBV/HCV endemic area of southern Taiwan. Eligible subjects aged 40-65 years (n=9934) underwent testing of hepatitis B surface antigen (HBsAg), HCV antibody (anti-HCV) and other related biochemical profiles. Urinalysis with repeated dipstick for proteinuria detection was performed. Anti-HCV-positive rate amongst proteinuria subjects was significantly higher than nonproteinuria subjects (9.6% vs. 6.2%, P<0.001). By contrast, HBsAg-positive rate did not differ between subjects with and without proteinuria (13.0% vs. 13.8%, P=0.57). Prevalence of proteinuria amongst anti-HCV-positive subjects (10.2%) was significantly higher than that in HBsAg-positive subjects (6.4%, P=0.004) and in HBsAg-negative or anti-HCV-negative subjects (7.0%, P=0.004). The difference persisted even after excluding diabetics. Multivariate logistic regression analyses showed that diabetes was the most important significant factor associated with proteinuria, followed by hypertension, anti-HCV seropositivity, body mass index, age and triglyceride levels. We demonstrated the significant association between proteinuria and HCV, but not HBV, infection in this HBV/HCV-endemic area.