Trimethoprim-sulfamethoxazole-associated hepatotoxicity - part of a hypersensitivity syndrome.

Trimethoprim-sulfamethoxazole is a commonly used medication. Side effects are numerous and include drug hypersensitivity syndrome. The case of a 24-year-old woman with severe liver failure is presented. Erythema multiforme and thrombocytopenia developed after the acute onset of hepatotoxicity and after all medications had been stopped. Clinical resolution of all features occurred over weeks but laboratory abnormalities persisted up to eight months later. A causal link with sulfamethoxazole was supported by timing, liver biopsy and lymphocyte toxicity test. This case illustrates one presentation and the possible severity of the drug hypersensitivity syndrome associated with trimethoprim-sulfamethoxazole.