Is hepatitis B surface antigen (HB s Ag) enough alone as a screening test for HBV infection in rheumatic disease patients before starting immunosuppressive therapies? A cross sectional study.

BACKGROUND & OBJECTIVES: Prevalence of hepatitis B virus in patients with rheumatic diseases has been reported differently among studies. The loss of immune control in these patients may result in the reactivation of HBV replication within hepatocytes. Considering the lifelong use of multiple anti-rheumatic drugs, screening for HBV is recommended before starting immunosuppressive or immunomodulatory therapy. The aim of this study was to select the best and simplest test for screening of HBV in rheumatic patients. METHODS: This study was carried out on 102 patients with different rheumatic diseases. Screening to all patients by hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) antibodies and human immune deficiency virus antibodies (HIV) were done. HBV core antibodies and real time PCR to detect HBV DNA were done. RESULTS: The mean age of the patients was 37.18 +/- 12.37 years, 3.9% of them were males and 96.1% were females. HBsAg had 100% Sensitivity, 100% Specificity, 100% PPV, 100% NPV and 99.0% accuracy. While, anti-HBc had 100% Sensitivity, 78% Specificity, 8% PPV, 100% NPV and 78% accuracy in screening of HBV. CONCLUSIONS: HBs Ag was found to be superior to antiHBc for screening for HBV infection in rheumatic patients.