Iman Pouladi - Department of Medical Microbiology, Faculty of Medicine, Shahed University, Tehran, Iran
Reza Mirnejad - Molecular Biology Research Center, System biology and Poisoning institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
Susan Rostampur - Student Research Committee of faculty paramedicine, Iran University of Medical Sciences, Tehran, Iran
Soghra Viesy - Department of Medical parasitology, Faculty of paramedicine, Ilam University of Medical Sciences, Ilam, Iran
Mohammad Niakan - Department of Medical Microbiology, Faculty of Medicine, Shahed University, Tehran, Iran

Background: Mycoplasma pneumoniae is a common cause of community-acquired pneumonia. The global increased resistance of M. pneumoniae strains to macrolide (ML) has become a worrisome health problem. The widespread use of these medications has led to increased rate of reported ML-resistant M. pneumoniae (MRMP) throughout the world. This study was aimed to evaluate the resistance of M. pneumoniae against erythromycin due to mutations in the 23S rRNA gene of patients with respiratory infections in Iran. Methods: In this study, 100 samples of throat swab from a patient with respiratory problems were collected. After the cultured of all samples in M. pneumonia-specific PPLO medium, PCR technique was performed with specific primers. Afterwards, the broth micro-dilution MIC assay was employed. Finally, the PCR product of the 23S rRNA gene was sequenced to detect mutations of domain V in 23S rRNA gene of MRMP. Results: It was found that 17 cases (17%) were positive for mycoplasma genus and six cases (6%) positive for M. pneumoniae species. Also, analysis of the sequence of 23S rRNA gene, revealed that one of the samples had mutations at positions A2431G and G2491A. All positive samples M. pneumoniae with 23S rRNA gene were sensitive to erythromycin. Conclusions: These use of these antibiotics should be limited to prevent the emergence of MRMP in Iran.

Keywords: Erythromycin, Macrolide resistance, Mycoplasma pneumoniae, 23S rRNA gene.