Clinical Characteristics and Drug Resistance Profile of Mycobacterium colombiense Infection: A Study of 22 Cases

Lin Mei,1,2,* Feng Liang,1,* Shengsheng Liu,2 Hua Chen1 1Guangzhou Chest Hospital, Guangzhou, People’s Republic of China; 2Department of Tuberculosis, Anhui Chest Hospital, Hefei, People’s Republic of China*These authors contributed equally to this workCorrespondence: Hua Chen, Guangzhou Chest Hospital, No. 62 Hengzhigang Road, Guangzhou, People’s Republic of China, Tel +86-13570550192, Fax +86- 02083595977, Email [email protected]: Mycobacterium colombiense, a rare yet clinically significant species within the Mycobacterium avium complex, demonstrates a marked propensity for disseminated disease and is associated with high mortality. However, data on its clinical characteristics and drug resistance profiles remain scarce. This study aims to conduct an in-depth analysis of the clinical characteristics and drug resistance profile of Mycobacterium colombiense disease, providing insights for optimizing its diagnosis and treatment strategies.Patients and Methods: We retrospectively analyzed the clinical data of 22 HIV-negative patients diagnosed with Mycobacterium colombiense disease at Guangzhou Chest Hospital from April 2021 to April 2024. Data included clinical manifestations, laboratory findings, and treatment regimens.Results: Among the 22 confirmed cases, disseminated Mycobacterium colombiense disease accounted for 63.6% (14/22), primarily involving the lungs, bones and joints, serous cavities, and lymph nodes. Common symptoms included cough/sputum production, fatigue/weight loss, fever, bone pain, and subcutaneous abscesses/skin ulcers. All patients tested positive for Mycobacterium colombiense via tNGS, while 19 cases were concurrently confirmed through culture of sputum or bronchoalveolar lavage fluid as part of the Mycobacterium avium complex. All patients received combined anti-nontuberculous mycobacterial therapy. Drug susceptibility testing performed in 11 cases revealed high sensitivity to bedaquiline, clofazimine, rifabutin, ethambutol, and rifampin.Conclusion: Mycobacterium colombiense infection is prone to causing disseminated disease, affecting multiple organ systems with diverse clinical presentations. Timely therapeutic intervention can improve patient prognosis to some extent. This study offers valuable references for the clinical diagnosis and treatment of Mycobacterium colombiense infection, underscoring its practical significance in clinical practice.Keywords: Mycobacterium colombiense, disseminated infection, drug susceptibility testing, nontuberculous mycobacteria, clinical characteristics