Gene subtype analysis of for drug resistance to azithromycin.

Azithromycin has been widely used for the treatment of . However, the drug resistance of for azithromycin is currently increasing. The aim of the present study was to analyze the association between gene subtypes of and drug resistance for azithromycin. The gene subtypes of were assayed by a polymerase chain reaction technique. Drug resistance of was analyzed using an antimicrobial susceptibility test. The results demonstrated that gene type presented higher drug resistance compared with and gene types of . Gene type was identified as eight gene subtypes (14a/f, 14e/f, 12e/f, 12d/f, 6d/f, 11d/f, 14j/f and 8d/f) among 324 cases. It was identified that 23S rRNA A2058G mutation was observed in gene subtypes 14a/f, 14e/f and 12e/f. A2059G mutation occurred in the gene subtypes 8d/f, 12d/f, 6d/f, 11d/f and 14j/f. The proportions of azithromycin-resistant genotypes harboring either the A2058G or the A2059G mutation among the strains were 34.2 and 65.8%, respectively. The antimicrobial susceptibility test demonstrated that A2059G mutations exhibited a higher drug resistance for azithromycin compared with A2058G mutations. In conclusion, these results indicate that azithromycin resistance in is associated with gene subtype, which may contribute to the treatment of .