Trimethoprim-sulfamethoxazole-induced lung injury: a case report.

Background: Trimethoprim-sulfamethoxazole (TMP-SMX) is a commonly used antibiotic. While cutaneous adverse drug reactions associated with TMP-SMX are commonly recognized, lung toxicity induced by TMP-SMX is an unusual condition, with scattered reports of hypersensitivity pneumonitis, acute fibrinous organizing pneumonia, interstitial lung disease and acute respiratory distress syndrome. Reports of TMP-SMX-associated drug-induced lung injury (DLI) are rare in the pediatric population and its pathogenesis is not well understood. Diagnosis of DLI remains a challenge, given the wide range of clinical presentations that overlap with other conditions and the lack of diagnostic tests. In this report, we describe a case of TMP-SMX-induced lung injury in an eight-year-old child. Case Description: An eight-year-old girl presented in respiratory failure with acute symptoms of shortness of breath, fever, maculopapular rash and vomiting. This was associated with pneumonitis, pneumothorax, pneumomediastinum and subcutaneous emphysema on imaging. She had been on 25 days of TMP-SMX for treatment of Group D Conclusions: Diagnosis of DLI can be challenging. The early identification of DLI and discontinuation of culprit drug is essential in its management. Further understanding of the underlying pathophysiology and risk factors for TMP-SMX-associated DLI is required.