Abstract:

Objective To understand the distribution and epidemiological characteristics of non-tuberculous mycobacterium (NTM) strains in Fujian Province and provide references for development of the provincial NTM control strategies. Methods The strain specimens were collected from 190 suspects with NTM infection, who were detected by sputum culture examination in the 11 drug-resistant tuberculosis (TB) surveillance sites, and the fluorescence PCR melting curve method was performed to do the strain identification. Excel 2016 and SPSS 24.0 software were used to manage and analyze the data. Nonparametric test was used to analyze the distribution of NTM strain in patients with different demographic characteristics and Chi square test was performed to compare the characteristics differences between the patients infected with M.intracellular and noncellular NTM. P value <0.05 was considered statistically significant. Results A total of 161 patients were confirmed to be infected by NTM, including 153 patients were infected by 8 kinds of strains and the strains were not identified in the other 8 patients. Most of patients were infected with M.intracellular (60.9%, 98/161), followed by M.abscessus (19.9%, 32/161). The average age of the patients infected with NTM was (57.3±13.0) years old, and most of them were male (70.2%,113/161), local resident (87.0%, 140/161), migrant workers (72.7%, 117/161), Han nationality (97.5%, 157/161) and living in coastal cities (77.6%, 125/161). In the patients infected with either M.intracellular or noncellular NTM, the highest proportions of the infection were in the 45-60 age groups respectively (63.3% (62/98) and 57.2% (36/63)), and were male (71.4% (70/98) and 68.3% (43/63)], migrant workers (76.5% (75/98) and 66.7% (42/63)), local residents (88.8% (87/98) and 84.1% (53/63)) and living along the coast (74.5% (73/98) and 82.5% (52/63)); those proportions did not have significate differences between the patients infected with M.intracellular or noncellular NTM (χ ²=4.202, 0.185, 1.879, 0.731, 1.431 respectively and all P values were >0.05). The proportion of Han nationality was significant difference between the patients infected with M.intracellular (100.0% (98/98)] and noncellular NTM (93.7% (59/63)) (χ ²=4.029, P<0.05)). Conclusion The patients infected with NTM in Fujian were mainly Han nationality, local resident, male, middle aged and old people, and migrant workers; most of the them were infected with M.intracellular, followed by M.abscess. Except for nationality, the social-demographic characteristics did not have significant differences between the patients infected with M.intracellular and noncellular NTM.

Key words: Mycobacteria,atypical, Disease attributes, Epidemiologic studies, Fujian Province