Mesenchymal Stem Cell-derived Exosomes for the Treatment of Bronchiectatic Nontuberculous Mycobacterial Pulmonary Disease.

Nontuberculous mycobacterial pulmonary disease (NTM-PD) is a chronic and challenging infectious condition with rising global prevalence, and its bronchiectatic subtype is particularly difficult to treat with conventional regimens due to frequent adverse effects, thus necessitating novel therapeutic approaches. This report presents a 42-year-old female patient diagnosed with bronchiectatic NTM-PD, characterized by persistent cough, sputum production, and hemoptysis, which was confirmed through radiological findings and microbiological testing. Following intolerance to conventional antimicrobial therapy, the patient was treated exclusively with nebulized inhalation of human umbilical cord mesenchymal stem cell-derived exosomes (HucMSC-Exos). This intervention led to significant alleviation of respiratory symptoms, stabilization of pulmonary function, and marked improvement in immunological parameters. In conclusion, nebulized HucMSC-Exos therapy demonstrated successful outcomes in this case, improving clinical symptoms, pulmonary function, and immune status, which suggests its potential as a viable and innovative therapeutic strategy for managing this complex condition and warrants further clinical investigation.