Identification of Mycobacterium spp. Isolates From Suspected Tuberculosis Patients Using Molecular Methods in Zahedan, Iran

Introduction: Tuberculosis is one of the oldest zoonotic diseases, with a high prevalence in many low-income countries. Specific and sensitive tuberculosis diagnostic methods in the early stages play a significant role in saving the lives of patients. There is little data available in Zahedan on the prevalence of the Mycobacterium species, so this study aimed to identify the Mycobacterium species in patients with pulmonary tuberculosis in Zahedan.Materials & Methods: This study included ۵۰۰ samples collected from sputum in Zahedan. The samples were cultured on LJ and simultaneously stained with cold Ziehl-Neelsen (ZN). After growth, DNA was extracted and used for molecular identification of the Mycobacterium species from the samples. RD typing was used to differentiate members of the Mycobacterium tuberculosis complex. Finally, the PCR-RFLP method was used as a comparison method. Results: The typical ۵۴۳ bp band was observed in all isolates via amplicon PCR-۱۶S rRNA, emphasizing that all isolates belong to the genus Mycobacterium. Sixty isolates were identified as belonging to the MTBC and were classified as M. tuberculosis species. The PCR-RFLP analysis using Alu I on the oxyR gene confirmed that all ۶۰ isolates were M. tuberculosis. Three samples (۴.۷%) were also positive for Nontubercolous mycobacteria (NTM). One isolate was categorized in the M. terrae complex group (MTC), and two isolates belonged to the M. simiae group.Conclusion: Our results indicated that M. tuberculosis has a high prevalence in the human population of this city. Therefore, screening these individuals plays a significant role in reducing the prevalence of the disease in Zahedan. It is suggested that further studies be conducted on the human population to find Mycobacterium strains in the future.

کلیدواژه ها:

Mycobacterium tuberculosis ، NTM ، PCR ، PCR-RFLP ، Zahedan