Evaluation of patient-related factors associated with causality, preventability, predictability and severity of hepatotoxicity during antituberculosis [correction of antituberclosis] treatment

For evaluation the extent of antituberculosis drug-induced hepatotoxicity and also to determine the patient-related factors associated with causality, preventability, predictability and severity of hepatotoxicity induced by antituberculosis medications, a prospective study was conducted on 112 patients in a tertiary care university teaching hospital for three years. Causality, preventability, predictability and severity of hepatotoxicity were determined based on the available standard algorithms. Of 112 patients, 31 (27.7%) demonstrated hepatotoxicity. Two patients died from complications of liver-related illness. The mean duration of treatment before the onset of hepatotoxicity was 16.7+/-3.2 days. Malnutrition was present in 17 of 112 patients. Most of hepatotoxicity (25/31 or 80.6%) occurred within the first month of treatment. Reintroduction of antituberculosis drugs was possible in 29 of 31 patients. Univariate and multivariate analysis did not show significant relationships between the rate of hepatotoxicity with age, sex, nutrition and nationality. Our results showed that hepatotoxicity induced by antituberculosis drugs is a nonpreventable and unpredictable reaction. The causality of this reaction is classified as category A based on European grading of causality. This study noted that the frequency of hepatotoxicity induced by antituberculosis drugs in Iranian patients is higher than other studied populations.