Archives of Pediatric Infectious Diseases Archives of Pediatric Infectious Diseases Arch Pediatr Infect Dis http://www.pedinfect.portal.tools 2322-1828 2322-1836 10.5812/pedinfect en jalali 2019 9 17 gregorian 2019 9 17 5 2
en 10.5812/pedinfect.40001 rpoB Gene Sequencing for Identification of Rapidly Growing Mycobacteria <italic>rpoB</italic> Gene Sequencing for Identification of Rapidly Growing Mycobacteria research-article research-article Conclusions

rpoB gene sequencing has a high discriminatory power, which easily permits the identification of clinical isolates of RGM to the species level. It unambiguously differentiates between closely related species with restricted biochemical and PRA differences. This procedure is suggested as a first-line identification method for RGM.

Background

Rapidly growing mycobacteria (RGM) are increasingly recognized as a cause of human infections. Rapid and reliable identification of RGM at species level should be carried out as a means of effective patient managements.

Methods

Twenty clinical samples of RGM isolated from suspected tuberculosis (TB) patients were included. Different phenotypic tests and a hsp65-PCR restriction analysis (PRA) method were used to identify the isolated organisms to species level. Sequence analysis of the rpoB gene was also used for molecular identification of clinical isolates.

Results

Phenotypic evaluation of clinical isolates assigned 19 (95%) isolates of RGM to M. fortuitum complex. Using hsp65-PRA, 13 isolates of M. fortuitum complex were identified as M. fortuitum, 4 isolates as M. abscessus and 1 isolates as M. chelonae. However, two isolates had identical hsp65-PRA patterns; one was indistinguishable from M. conceptionense and M. senegalense and another was indistinguishable from M. peregrinum and M. porcinum. By the rpoB gene sequence analysis, all species studied were readily discriminated from each other.

Conclusions

rpoB gene sequencing has a high discriminatory power, which easily permits the identification of clinical isolates of RGM to the species level. It unambiguously differentiates between closely related species with restricted biochemical and PRA differences. This procedure is suggested as a first-line identification method for RGM.

Background

Rapidly growing mycobacteria (RGM) are increasingly recognized as a cause of human infections. Rapid and reliable identification of RGM at species level should be carried out as a means of effective patient managements.

Methods

Twenty clinical samples of RGM isolated from suspected tuberculosis (TB) patients were included. Different phenotypic tests and a hsp65-PCR restriction analysis (PRA) method were used to identify the isolated organisms to species level. Sequence analysis of the rpoB gene was also used for molecular identification of clinical isolates.

Results

Phenotypic evaluation of clinical isolates assigned 19 (95%) isolates of RGM to M. fortuitum complex. Using hsp65-PRA, 13 isolates of M. fortuitum complex were identified as M. fortuitum, 4 isolates as M. abscessus and 1 isolates as M. chelonae. However, two isolates had identical hsp65-PRA patterns; one was indistinguishable from M. conceptionense and M. senegalense and another was indistinguishable from M. peregrinum and M. porcinum. By the rpoB gene sequence analysis, all species studied were readily discriminated from each other.

Mycobacterium;Sequencing;Iran;rpoB Gene Mycobacterium;Sequencing;Iran;rpoB Gene http://www.pedinfect.portal.tools/index.php?page=article&article_id=40001 Mohammad Javad Nasiri Mohammad Javad Nasiri Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran Abdolrazagh Hashemi Shahraki Abdolrazagh Hashemi Shahraki Department of Epidemiology, Pasteur Institute of Iran, Tehran, Iran Department of Epidemiology, Pasteur Institute of Iran, Tehran, Iran Abbas Ali Imani Fooladi Abbas Ali Imani Fooladi Applied Microbiology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran Applied Microbiology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran Hossein Dabiri Hossein Dabiri Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Professor in Medical Microbiology, Department of Microbiology, Shahid Beheshti University of Medical Sciences, School of Medicine, Tehran, Iran Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Professor in Medical Microbiology, Department of Microbiology, Shahid Beheshti University of Medical Sciences, School of Medicine, Tehran, Iran Mohammad Mehdi Feizabadi Mohammad Mehdi Feizabadi Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran