Hepatotoxicity induced by trimethoprim-sulfamethoxazole in a child with cystic fibrosis.

Patients with cystic fibrosis (CF) have chronic and progressive lung infections with various bacterial organisms that require treatment with oral and intravenous antibiotics on a regular basis. Trimethoprim-sulfamethoxazole (TMP-SMX) is one of the medications used to treat acute pulmonary infectious exacerbations in patients with CF. Hepatic toxicity secondary to TMP-SMX was previously described in normal subjects but has not been reported in children with CF. Here we describe a 14-year-old female child with CF who was given oral TMP-SMX for an acute pulmonary infectious exacerbation. She developed a rash, severe constitutional symptoms, and significant elevation of liver enzyme concentrations secondary to immunity-mediated reaction to TMP-SMX. Discontinuation of TMP-SMX and supportive treatment led to resolution of her symptoms and normalization of liver enzyme concentrations.