Background: Whether antituberculosis (anti-TB) treatment in patients with chronic viral hepatitis affects the incidence and onset time of drug-induced hepatotoxicity (DIH) is still controversial. The aim of this retrospective study was to find out whether chronic viral hepatitis affects the incidence and onset time of DIH.
Methods: All patients diagnosed with active TB and being treated at a tertiary referral hospital between 2002 and 2009 were identified from medical records, from which 553 patients were enrolled in the study. The incidence and onset of DIH in patients with and without chronic viral hepatitis (controls) were compared.
Results: The incidence of DIH was similar in patients with and without chronic hepatitis (8 % [32/392] vs. 7 % [11/161], P > 0.05). The incidence of transient liver function impairment (TLI) was significantly lower in controls than in chronic hepatitis patients (2 % [9/392] vs. 12 % [20/161], P < 0.001. The mean onset times of DIH in the control, hepatitis B virus (HBV), and hepatitis C virus (HCV) groups were not significantly different (40, 39, and 67 days, respectively, all P > 0.05). The mean onset times of TLI in the control, HBV, and HCV groups were significantly different (23, 48, and 68 days, respectively, all P < 0.05).
Conclusions: Liver function impairment during anti-TB therapy in patients with chronic viral hepatitis was due to mostly TLI, with TLI occurring later than in controls. Chronic viral hepatitis had no significant effect on the incidence of DIH.