Abstract:

Objective To investigate the infection trend, distribution characteristics and prevalence of non-tuberculosis mycobacteria (NTM) infection in Hunan Province from 2012 to 2017, and provide reference for the prevention and treatment of NTM disease. Methods A total of 15576 patients were collected from 14 cities who were diagnosed as mycobacterial infections in the Hunan Chest Hospital by BACTEC MGIT 960 from 2012 to 2017, including 11126 males and 4450 females. 15576 strains of mycobacteria isolated (1 strain per patient). M.tuberculosis complex and NTM were identified by MPB64 colloidal gold and p-nitrobenzoic acid (PNB) growth test. NTM strains were for further strains identification by 16S rRNA and Hsp65 sequencing. Clinical datas of NTM infected patients were also collected and analyzed. Results The overall prevalence of NTM infection was 10.17% (1584/15576) between 2012 and 2017. The prevalence of NTM infection among the male patients was 62.06% (983/1584)which was higher than that among the female patients (37.94%,601/1584).The age distribution was dominated by the patients aged 40- years, accounting for 39.02% (618/1584). Occupation distribution was dominated by farmers, accounting for 66.67% (1056/1584). Twenty-four species were identified and the top four species were M.intracellular (25.23%,84/333), M.abscessus (24.62%,82/333), M.gordonae (18.62%,62/333) and M.avium (16.82%,56/333) in 2016. Twenty-one species were identified and the top four species were also M.intracellular (27.15%,104/383), M.abscesus (22.46%,86/383), M.gordonae (21.15%,81/383) and M.avium (17.49%,67/383) in 2017. Conclusion The prevalence of NTM infection in Hunan Province is high, and majorities of patients with NTM infection are mainly attributed to groups such as male patients, middle-aged and elderly and farmers, and the pathogenic NTM take the main proportion.

Key words: Mycobacterium infections, Mycobacteria,atypical, Disease attributes, Sequence analysis,DNA