Narjes Noori Goodarzi1, Mohammad Reza Pourmand1, Maryam Arfaatabar1, Ghasem Azimi2, Ensieh Masoorian1, Abbas Rahimi Foroushani3, Farzaneh Aminharati1, Siamak Heidarzadeh4, Akram Baghani5. 1. Department of Pathobiology, School of Public Health and Biotechnology Research Center, Tehran University of Medical Sciences, Tehran, Iran. 2. Department of Internal Medicine, Shahid Mostafa Khomeini Hospital, Shahed University, Tehran, Iran. 3. Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. 4. Department of Microbiology and Virology, Zanjan University of Medical Sciences, Zanjan, Iran. 5. Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Abstract
Objectives: Increasing macrolide resistance of Mycoplasma pneumoniae strains is becoming a public health concern worldwide. Nevertheless, no comprehensive genomic background of circulating isolates is available in our region. We aimed to study the genetic diversity of this microorganism using the multiple-locus variable-number tandem-repeat analysis method and to investigate the relationships between MLVA types and macrolide susceptibility profiles of the isolates. Materials and Methods: A total of 270 patients attending Tehran general university hospitals were included in this study. One throat swab was taken from each patient. M. pneumoniae was identified using culture and PCR assay. Macrolide resistance was determined using the broth microdilution method. The MLVA was performed by amplification of four variable-number tandem-repeat loci. Results: Of 270 specimens, M. pneumoniae was detected in 25.2% (n = 68) and 21.8% (n = 59) samples using PCR and culture, respectively. Approximately 56.9% of isolates were resistant to macrolides. Fifty-one of 59 M. pneumoniae isolates were divided into 6 distinct MLVA types. Conclusion: The macrolide-resistant M. pneumoniae (MRMP) rate in this study was relatively high and most of the MRMP isolates were assigned into the type 4/5/7/2. Since a significant association between MLVA type 4/5/7/2 and macrolide resistance of M. pneumoniae isolates was observed, further monitoring of genetic diversity of MRMP isolates might facilitate better understanding of epidemiology of this microorganism. Besides surveillance of the antibiotic susceptibility might be helpful to make necessary reconsiderations on guidelines for treatment of M. pneumoniae infection.
Objectives: Increasing macrolide resistance of Mycoplasma pneumoniae strains is becoming a public health concern worldwide. Nevertheless, no comprehensive genomic background of circulating isolates is available in our region. We aimed to study the genetic diversity of this microorganism using the multiple-locus variable-number tandem-repeat analysis method and to investigate the relationships between MLVA types and macrolide susceptibility profiles of the isolates. Materials and Methods: A total of 270 patients attending Tehran general university hospitals were included in this study. One throat swab was taken from each patient. M. pneumoniae was identified using culture and PCR assay. Macrolide resistance was determined using the broth microdilution method. The MLVA was performed by amplification of four variable-number tandem-repeat loci. Results: Of 270 specimens, M. pneumoniae was detected in 25.2% (n = 68) and 21.8% (n = 59) samples using PCR and culture, respectively. Approximately 56.9% of isolates were resistant to macrolides. Fifty-one of 59 M. pneumoniae isolates were divided into 6 distinct MLVA types. Conclusion: The macrolide-resistant M. pneumoniae (MRMP) rate in this study was relatively high and most of the MRMP isolates were assigned into the type 4/5/7/2. Since a significant association between MLVA type 4/5/7/2 and macrolide resistance of M. pneumoniae isolates was observed, further monitoring of genetic diversity of MRMP isolates might facilitate better understanding of epidemiology of this microorganism. Besides surveillance of the antibiotic susceptibility might be helpful to make necessary reconsiderations on guidelines for treatment of M. pneumoniae infection.