Distribution and epidemiological characteristics of nontuberculous mycobacterium species in jianghan plain

Pulmonary nontuberculous mycobacteria (NTM) disease is an increasing public health concern in China. This study aimed to describe the epidemiology of pulmonary NTM disease in the Jianghan Plain region of Central China. From 2021 to 2023, we collected specimens with positive mycobacterial cultures from the Jianghan Plain and identified species using fluorescence PCR melting curve analysis. We documented demographic characteristics, treatment history, laboratory examination results, and comorbidities of patients with pulmonary NTM disease. From 2021 to 2023, 419 cases of NTM were identified among 5,608 clinical specimens collected from the Jianghan Plain, accounting for 7.47% (419/5,608) of isolates. Among patients with pulmonary NTM, ages ranged from 16 to 90 years, with a median age of 64 years. The majority of cases (56.32%) occurred in patients over 60 years of age. The predominant species identified were Mycobacterium intracellulare (224 cases, 53.46%), Mycobacterium abscessus (91 cases, 21.72%), Mycobacterium avium (27 cases, 6.44%), Mycobacterium gordonae (25 cases, 5.97%), and Mycobacterium kansasii (19 cases, 4.53%). The risk of developing Mycobacterium abscessus disease significantly decreased with advancing age. Compared to patients with Mycobacterium intracellulare disease, those with pulmonary Mycobacterium abscessus disease were significantly more likely to present with hemoptysis. No other significant differences in tuberculosis history or comorbidities were observed between patients with Mycobacterium intracellulare and Mycobacterium abscessus infections. The isolation rate of NTM in the Jianghan Plain from 2021 to 2023 remained stable, slightly exceeding the national average in China. Mycobacterium intracellulare was the most prevalent pathogenic NTM species, followed by Mycobacterium abscessus. Hemoptysis was identified as an independent risk factor for pulmonary disease caused by M. abscessus.