Mycobacterium abscessus infection in a young man with cystic fibrosis: a case report and literature review

Background Cystic fibrosis (CF) is a rare autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Although relatively common in Caucasian populations, CF is rare in China, where it frequently presents with non-specific respiratory symptoms, leading to delayed diagnosis and frequent coinfections with multidrug-resistant pathogens. Case report A 21-year-old man presented with a 6-year history of recurrent productive cough and intermittent fever over the past 6 months. Imaging revealed bronchiectasis with evidence of infection. Metagenomic next-generation sequencing of bronchoalveolar lavage fluid identified Staphylococcus aureus and Mycobacterium abscessus . Further investigations revealed pancreatic lipomatosis, congenital absence of seminal vesicles, and fat-soluble vitamin deficiencies. CF diagnosis was confirmed by elevated sweat chloride concentration (88 mmol/L) and biallelic CFTR mutations. Clinical stability was achieved through a quadruple antimycobacterial regimen (linezolid, moxifloxacin, azithromycin, and minocycline) combined with systemic supportive care. CFTR modulator therapy was deferred due to limited access and financial constraints. Conclusion We report a case of CF in a Chinese patient presenting with nontuberculous mycobacterial infection, a condition rarely documented in East Asian populations. We provide a review of the relevant literature, aiming to emphasize the importance of early recognition of CF, personalized antimicrobial strategies, and improved access to essential medications.