Antibiotic susceptibility pattern and identification of quinolone-resistant strains of Klebsiella pneumoniae clinical specimens from Khorramabad, Iran

作者：Azadpour M; Soleimani Y; Rezaie F; Rezaeifar M^*

来源：Tropical Biomedicine, 2017, 34(2): 412-418.

The present investigation is designed to evaluate antibiotic susceptibility pattern and identification of qnr strains of Klebsiella pneumoniae in clinical specimens isolated from general hospitals in Khorramabad, Iran. Total of 107 K. pneumoniae isolates were randomly collected since December 2011 until September 2012 from hospitalized patients at general hospitals in Khorramabad, Iran. The isolates were collected from different clinical samples including urine, sputum, lesion, and blood. Biochemical tests were performed for identification of isolates. Antibiotic susceptibility test was performed using disc diffusion method according to recommendations of Clinical and Laboratory Standards Institute using 13 antibiotic disks. K. pneumoniae 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. Chi-square test was used to analysis and P value of < 0.05 was considered statistically significant. All clinical isolates were confirmed as K. pneumoniae by complete biochemical identification (gram staining, oxidase negative, indole positive, Simon's citrate positive and urease positive). Forty-three (40.2%) out of 107 isolates were multidrug-resistant (MDR). Ciprofloxacin (quinolone) susceptibility testing showed that 34 isolates (31.8%) were resistant, 7 isolates (6.5%) were intermediately resistant and 66 isolates (61.7%) were sensitive. Eighteen (16.8%) out of 107 K. pneumoniae clinical isolates were positive for qnr genes. 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). Findings of the present study indicated high frequency of qnr-positive K. pneumoniae in Lorestan province, Iran. However, there is no association between quinolone resistance and presence of qnr genes in isolates of K. pneumoniae.

• 出版日期2017-6