Pulmonary Infection Caused by Mycolicibacterium neoaurum: The First Documented Case in Morocco

Nontuberculous mycobacteria (NTM) are increasingly recognized as causes of human infection. Mycolicibacterium neoaurum (formerly Mycobacterium neoaurum), a rapidly growing mycobacterium, is a rare pathogen, usually associated with catheter-related bloodstream infections. Pulmonary involvement is exceptional. We report the first documented case of pulmonary infection due to Mycobacterium neoaurum (M. neoaurum) in Morocco. A 39-year-old man with type 2 diabetes mellitus and refractory ulcerative colitis was hospitalized for severe autoimmune blistering disease and subsequently developed fever, productive cough, night sweats, and hypoxemia. Laboratory findings were indicative of an inflammatory syndrome. Chest imaging revealed a right upper lobe cavitary lesion. Bronchoalveolar lavage culture yielded acid-fast bacilli after eight days, identified as M. neoaurum by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF). Empirical ciprofloxacin therapy administered for four weeks resulted in marked clinical and biological improvement. This case highlights the rare pulmonary pathogenicity of M. neoaurum and underscores the importance of considering uncommon NTM in cavitary lung disease, particularly in patients with complex comorbidities. Advanced diagnostic tools, such as MALDI-TOF, are crucial for accurate identification.