other جهش در ژن‌های gyrA و parC در ایزوله‌های مقاوم به کینولولون کلبسیلا پنومونیه از بیمارستان‌های بروجرد Medical Biology Medical Biology مقاله پژوهشی Original Research Article <p style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:times new roman;"><span style="color:#008080;"><strong>Background and Objective</strong></span><strong>: </strong>Quinolones are the antibiotics used to treat infections. Several reports have indicated the increased resistance to quinolone in <em>K. pneumoniae</em> strains all over the world. The aim of this study is to investigate amino acid substitutions in GyrA and ParC proteins among quinolone-resistant isolates of <em>K. pneumoniae</em> in Borujerd <span dir="RTL">)</span>west of Iran<span dir="RTL">(</span> hospitals.<br> <strong><span style="color:#008080;">Materials and Methods</span><em>: </em></strong>Totally, 100 isolates of <em>K. pneumoniae</em> were collected. After validating the isolates by conventional laboratory methods, an antimicrobial susceptibility test was carried out for some antibiotics from the quinolones family. Quinolone resistance and Minimum Inhibitory Concentration (MIC) of Ciprofloxacin were detected by disk diffusion and E-test methods, respectively. The amplification of <em>gyrA</em> and <em>parC</em> genes in quinolone-resistant strains was performed by PCR using specific primers. PCR products were sequenced in order to detect the mutations in <em>gyrA</em> and <em>parC</em> genes.<br> <strong><span style="color:#008080;">Results</span>: </strong>Generally, 38% of all the collected isolates were resistant to Nalidixic acid and Ciprofloxacin, 18% were resistant to Ofloxacin, and 15% were resistant to Norfloxacin. Concurrent resistance to Nalidixic acid, Ciprofloxacin, Ofloxacin, and Norfloxacin was determined in 15% of the cases. In 86% (n=20) of Ciprofloxacin-resistant strains, MIC was measured 128 &mu;g/mL. The mutation rate was 40% (n=9) in <em>gyr</em>A gene in quinolone-resistant strains and 35% (n=8) in <em>par</em>C gene.<br> <span style="color:#008080;"><strong>Conclusion: </strong></span>Briefly, our research findings reveal that relatively high resistance to quinolones as well as fluoroquinolone was observed among <em>K. pneumoniae</em> isolates in Brojurd hospitals. It is likely that mutation occurrence in certain positions of <em>gyr</em>A and <em>par</em>C genes has a significant effect on developing high-level resistance to quinolone in <em>K. pneumoniae.</em></span></span></p> Klebsiella pneumoniae, gyrA and parC mutations, Quinolone resistance 1 7 http://journal.zums.ac.ir/browse.php?a_code=A-10-1508-2&slc_lang=other&sid=1 Leili Shokoohizadeh لیلی شکوهی زاده 5200319475328460054441 5200319475328460054441 No Dept. of Medical Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran Mehrangiz Saniee مهرانگیز صانعی 5200319475328460054442 5200319475328460054442 No Dept. of Medical Laboratory Sciences, Borujerd Branch, Islamic Azad University, Borujerd, Iran Mohsen Mirzaee محسن میرزایی 5200319475328460054443 5200319475328460054443 No Dept. of Medical Laboratory Sciences, Borujerd Branch, Islamic Azad University, Borujerd, Iran Mohammad Taheri محمد طاهری motaheri360@gmail.com 5200319475328460054444 5200319475328460054444 Yes Dept. of Medical Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran