Prevalence and risk factors of isolated anti-HBc antibody and occult hepatitis B infection in hemodialysis patients: a nationwide study.

BACKGROUND Recent studies have demonstrated that prevention of hepatitis B virus (HBV) transmission remains a challenge in hemodialysis (HD) patients. The aim of this study is to explore factors which increase the possibility of occult HBV (OHB) infection in patients under HD in Iran. MATERIAL AND METHODS Among 2188 cases who spent an average of 60.2 ± 61.1 months under HD, we selected 103 cases with isolated antihepatitis B virus core antibody (anti-HBc) and 231 controls without any HBV, hepatitis D virus (HDV) and hepatitis C virus (HCV) serologic markers. Socio-demographic data, past medical history, and clinical signs and symptoms were assessed. RESULTS The frequency of checking hepatitis B serologic markers was 15.3%. The rate of OHB infection in HD patients who were monitored for their HBV markers was 4.9%. Cases with isolated anti-HBc had significantly higher percentage of positive HBV DNA [odds ratio: OR (95% confidence interval: 95% CI) = 12.1 (1.4-105)], visual disturbances [OR (95% CI) = 1.8 (1.1-3.03)], history of diabetes mellitus [OR (95% CI) = 2.1 (1.3-3.5)], higher age, higher age when dialysis started and were mostly married, illiterate, disabled and retired. Diabetes mellitus was the only independent predictor of HBV DNA status in cases with isolated anti-HBc. CONCLUSION In our region, OHB infection is prevalent among hemodialysis patients and displays a direct correlation with factors which are age related except diabetes mellitus. Thus, the presence of isolated anti-HBc should prompt the clinician to evaluate a possible OHB infection especially when it is detected in conjunction with a history of diabetes mellitus.