Liver injury during antituberculosis treatment: An 11-year study

Setting: Bispebjerg Hospital, Department of Pulmonary Medicine, tuberculosis referral center for the Municipality of Copenhagen. Objective: To evaluate routine procedure for the management of liver injury during antituberculosis treatment. Design: From 1983-1993, 765 patients for whom we could trace 752 files (98%) were treated at our ward with standard Danish treatment for tuberculosis. From 1983-1986 they received a three-drug (9-month) regimen and from 1986-1993 a four-drug (6-month) regimen consisting of isoniazid, rifampicin, ethambutol + pyrazinamide. Data from a retrospective chart review. Results: An increase in aspartate aminotransferase (AST) of more than twice the upper limit of normal (ULN) was recorded in 127 patients (16%). 66 had elevated AST before treatment; most of these were men with a daily alcohol consumption in excess of 60 g. In the remaining 61 patients (8%) AST increased during antituberculosis treatment. 30 of these patients were excessive alcohol consumers, and seven had alcoholic liver cirrhosis. Despite an increase in AST of median 6 x ULN (range 2-25 x ULN), it was possible to continue treatment in 31 (15 excessive alcohol consumers) or reintroduce it fully in 14 (12 excessive alcohol consumers). Only 16 patients (2%), including 11 women with no daily alcohol consumption, needed a modified regimen. These patients were older (P < 0.05), seven were jaundiced, and one had alcoholic liver cirrhosis. Hepatotoxicity was confirmed by challenge with pyrazinamide (n = 7), isoniazid (n = 6) and combined isoniazid/rifampicin (n = 1). No deaths were caused by hepatotoxicity. Conclusion: In spite of an increase in AST levels to approximately 6 x ULN during antituberculosis treatment, the drugs can be continued or reintroduced in full in most cases. Risk factors of hepatotoxicity included old age, female sex and extensive tuberculosis, and not alcohol consumption. Overall, hepatotoxicity during antituberculosis treatment can be monitored and managed easily.