A Case of Recurrent Pancreatitis Induced by Trimethoprim-Sulfamethoxazole Re-Exposure

A 32-year-old man presented with epigastric pain. He had a previous episode of acute pancreatitis of undetermined cause 2 years earlier. The patient had taken trimethoprim (80 mg) and sulfamethoxazole (400 mg) twice daily because of acute urethritis 3 days prior to admission. No definite cause of acute pancreatitis could be identified on baseline studies. A thorough history-taking revealed that the patient had an episode of acute pancreatitis while taking trimethoprim (80 mg) and sulfamethoxazole (400 mg) twice daily for 2 weeks for prostatitis prior to the previous admission. Therefore, a cause-and-effect relationship between trimethoprim-sulfamethoxazole (TMP-SMX) and repeated episodes of pancreatitis was highly suggested. The patient was presumably diagnosed as TMP-SMX-induced pancreatitis. The final diagnosis was TMP-SMX-induced pancreatitis. Since drugs are rare causes of acute pancreatitis and the diagnosis of drug-induced pancreatitis is difficult to establish, we report this interesting case along with a review of medical literature.