Background One-third of the world's population is thought to be infected with Mycobacterium tuberculosis (Mtb); the highest incidence rates for active disease are found in the WHO's South-East Asian and African regions. Hepatitis B virus (HBV) and Hepatitis C virus (HCV) each infect about 0.3% of the UK population. HBV/HCV are treatable but largely asymptomatic until advanced liver disease and/or cancer. Screening for HBV/HCV is recommended in high-risk individuals but is not routinely performed in TB patients. HBV/HCV share similar epidemiological “hotspots” to TB, and several studies, primarily in South America and East Asia, have shown an increased prevalence of HBV/HCV in TB patients and an association between HBV/HCV and Drug Induced Liver Injury (DILI) following anti-TB therapy. No such analysis has been performed in the UK.
Aims To assess
The prevalence of markers of HBV and HCV infection in patients undergoing anti-TB therapy.
Whether serological evidence of HBV/HCV increases risk of DILI.
Method A prospective study on 429 TB patients receiving anti-TB therapy in a diverse urban TB clinic. Serological markers of HBV/HCV/HIV infection were documented. ALT was measured prior to treatment and 2–4 weeks after treatment initiation. DILI was defined as an ALT rise of greater than 2-times upper limit of normal following a normal pre-treatment level (<40 IU/ml).
Results 58.7% of patients were from either South-East Asia or Africa. 61 (14.2%) patients were isolated anti-HBc antibody positive (Anti-HBc), 11 (2.6%) were Hepatitis B surface antigen positive (HBsAg) and 7 (1.6%) were HCV antibody positive. The prevalence of active HBV/HCV infection was significantly higher than the estimated UK prevalence in this urban TB clinic. Three (5.3%) patients with serological evidence of HBV/HCV had DILI compared to 25 (9.5%) of those without.
Conclusion HBV/HCV prevalence is higher among TB patients and routine screening for viral hepatitis should be considered in this group. DILI was not increased in patients with serological markers of HBV/HCV.