Species distribution characteristics of nontuberculous mycobacteria isolated from patients with acquired immunodeficiency syndrome in Shanghai

Abstract

Objective To investigate the species distribution characteristics of nontuberculous mycobacteria (NTM) in acquired immunodeficiency syndrome(AIDS) patients in Shanghai, and to provide evidences for clinical treatment. Methods A total of 775 Mycobacteria strains were isolated from patients (including 129 isolates from AIDS patients and 646 isolates from HIV-negative patients) admitted to Shanghai Public Health Clinical Center during 2015. All the species were identified by the sequence analysis of 16S rRNA gene and hsp65 gene. Differences in the species distribution were compared between patients with and without HIV infection. CD4+ T lymphocyte count was detected by flow cytometry and its relation with mycobacteria infection was also analyzed. Chi-square test was used for comparison between groups. Results The ratio of NTM isolation from HIV-negative patients was 15.79% (102/646), while that was 46.51% in AIDS patients (60/129), and the difference was statistically significant (χ2=61.38, P 50 cells/μL (20.00% and 15.38%, respectively) (χ2=4.048 and 6.524, respectively, both P 50 cells/μL. Conclusions The prevalence of NTM isolation is significant higher in AIDS patients than HIV-negative patients in Shanghai, and the most prevalent NTM species is MAC. The NTM infection in AIDS patients is related with low CD4+ T lymphocyte counts. Key words: Acquired immunodeficiency syndrome; Nontuberculous mycobacteria; Species identification