Журнал бактериологии и паразитологии

Абстрактный

Prevalence of qnr Genes and Antibiotic Susceptibility Patterns among Clinical Isolates of Klebsiella Pneumoniae in West of Iran

Mozhgan Azadpour, Younes Soleimani, Faranak Rezaie, Elnaz Nikanpour, Hossein Mahmoudvand and Sareh jahanbakhsh

Background: This study aimed to define prevalence of qnr genes and antibiotic susceptibility patterns among clinical isolates of K. pneumoniae in Lorestan province, west of Iran.

Methods: Totally, 107 K. pneumoniae isolates were randomly collected since December until September 2012 from hospitalized patients at general hospitals in Lorestan, Iran. The isolates were from different clinical samples including urine, sputum, etc. Biochemical characterizations were performed for detecting isolates. Antibiotic susceptibility testing by disk diffusion method was performed according to recommendations of Clinical and Laboratory Standards Institute using 12 antibiotic disks. K. pneumonia isolates were screened by multiplex PCR amplification of qnrA, qnrB and qnrS using specific primers and sequence analysis of amplified regions of the isolates was also performed.

Results: 43 (40.2%) out of 107 isolates were multidrug-resistant (MDR). Ciprofloxacin (Quinolone) susceptibility testing showed that 34 isolates were resistant, 7 isolates were intermediately resistant and 66 isolates were sensitive. 18 (16.8%) out of 107 K. pneumoniae clinical isolates were positive for qnr gene. Among all the qnr-positive isolates, 16 isolates (88.9%) carried qnrB, 1 isolate (5.55%) carried qnrS and the rest (5.55%) carried both qnrB and qnrS genes while no qnrA was detected in these clinical isolates. qnr determinants were detected in 8 (23.5%) of the ciprofloxacin-resistant isolates as well as 1 (14.3%) and 9 (13.6%) intermediate and sensitive isolates, respectively. No significant association was observed between ciprofloxacin resistance and presence of qnr genes (P>0.05).

Conclusion: Findings of the present study indicated that emergence of qnr determinants contributed to development and spread of quinolone resistance in Iranian isolates of K. pneumonia.