Relapsing Primary Cutaneous Nocardiosis in a Healthy Pediatric Patient.

Primary cutaneous nocardiosis is a rare superficial skin infection typically affecting adults with soil exposure, trauma history, or immunosuppression. This case documents an unusual occurrence in a healthy 15-year-old girl with no known risk factors, who experienced relapse following a 5-week course of oral trimethoprim-sulfamethoxazole. The case highlights the diagnostic challenges of nocardiosis, including its nonspecific presentation and need for prolonged culture incubation, as well as the importance of an extended course of antibiotics to prevent relapse, even in immunocompetent patients.