Prevalence of hepatitis C virus in patients with tuberculosis and its impact in the incidence of anti-tuberculosis drugs induced hepatotoxicity

Background: The prevalence of hepatitis C virus (HCV) infection among patients with tuberculosis (TB) has not been extensively investigated, and very limited data on rates of HCV co-infection among patients with TB exists. Hepatotoxicity is the major adverse effect of three of the first line anti-TB agents: isoniazid (INH), rifampin (RIF), and pyrazinamide (PZA). Chronic liver disease raises a risk of hepatotoxicity during anti-tuberculosis treatment, up to three to five times more than TB patients who do not have viral infection. Aim: To assess the prevalence of HCV infection in patients with tuberculosis and its impact in the incidence of anti-tuberculosis drug induced hepatotoxicity (DIH). Subjects and methods: The prevalence of HCV in patients with newly diagnosed pulmonary or extrapulmonary tuberculosis was estimated using polymerase chain reaction (PCR). Then patients were classified into 2 groups: group I (patients with HCV-TB coinfections) and group II (HCV-seronegative tuberculous patients). Baseline and monthly measuring liver transaminases was done before and following the start of 1st line anti-tuberculosis therapy. Results: The prevalence of HCV in patients with TB was 17.02%. Regarding DIH, in group I; 6 (40%) cases showed transient transaminase elevations and 6 (40%) cases developed DIH. In group II; 11 (20.75%) cases developed transient transaminase elevations and only 2 (3.78%) cases developed DIH, and there was a highly significant difference (< 0.01) between both groups. Regarding the severity of DIH, in group I; 4 cases were mild, one case was moderate and one case was severe. While in group II, no cases was with severe DIH. The risk factors for developing DIH during anti-tuberculosis therapy were; age >= 40, high baselines transaminases, ALP and total bilirubin, and low BMI. Most cases of DIH occurred during the 1st 4 weeks of starting anti-tuberculosis therapy (66.7% and 50% in group I and group II, respectively). Conclusions: Tuberculosis and hepatitis C virus co-infection is common, and elevation of liver functions during anti-tuberculosis therapy is not uncommon. HCV-positive patients with tuberculosis should be closely monitored during treatment especially if they had elevated baseline liver functions, old age and with low BMI. Monitoring should include the whole period of treatment, especially the 1st 2 months. (C) 2014 The Egyptian Society of Chest Diseases and Tuberculosis. Production and hosting by Elsevier B.V. All rights reserved.