en ميکروب شناسي Microbiology تحقيقي Original Paper <div><strong>ABSTRACT</strong><br> <a name="OLE_LINK20"></a><a name="OLE_LINK11"><strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Background and Objectives: </strong></a><em>Enterococcus</em> <em>faecalis</em> is a major cause of bacterial prostatitis, which can increase the risk of developing prostate cancer if mistreated or left untreated. The aim of this study was to evaluate resistance of <em>E.</em> <em>faecalis</em> strains isolated from patients with prostatitis to three <a name="_Hlk521004132">fluoroquinolones</a>.<br> <strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Methods:</strong> In this cross-sectional study, we collected urine specimen from 164 patients hospitalized in six hospitals in the Golestan Province, Iran. Biochemical and bacteriological tests were carried out to identify <em>E. faecalis</em> strains. Pattern of resistance to ciprofloxacin, levofloxacin and norfloxacin was studied using the agar disk diffusion method (Kirby-Bauer method). The broth microdilution test was performed to determine minimum inhibitory concentrations (MICs) of fluoroquinolones according to the CLSI <a name="_Hlk526364216">M100-S25 (2015) criteria</a>.<br> <strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Results:</strong> Of 164 isolates, 39 (23.8%) were identified as <em>E. faecalis.</em> Frequency of resistance to ciprofloxacin, norfloxacin and levofloxacin was 12.8%, 12.8% and 2.6%, respectively. The MIC₉₀ of ciprofloxacin against the isolates was <a name="_Hlk526436173">4 </a>&mu;g/ml, which was 4-fold lower than that of norfloxacin <a name="_Hlk526436150">(MIC₉₀=16</a>&mu;g/ml) and 2-fold lower than that of levofloxacin (MIC₉₀=8&mu;g/ml). We found no significant difference between the isolates in terms of resistant to the fluoroquinolones (P>0.01).&nbsp; <span dir="RTL"></span><br> <strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Conclusion: </strong>Our results show that <em>E. faecalis</em> is one of the most common causes of bacterial prostatitis, and fluoroquinolones are still effective for treating the infection despite the reports of fluoroquinolones resistance in Iran. Moreover, levofloxacin may be a more suitable and effective antibiotic than ciprofloxacin and norfloxacin for treatment of this infection.<br> <strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Keywords</strong>:<a name="OLE_LINK22"></a><a name="OLE_LINK21"> <em>Enterococcus</em> <em>faecalis</em>, Prostatitis, Drug Resistance</a>, Iran.</div> Enterococcus faecalis, Prostatitis, Drug Resistance, Iran. 29 33 http://mlj.goums.ac.ir/browse.php?a_code=A-10-575-2&slc_lang=en&sid=1 Leila Fozouni lili_kia@yahoo.com 100319475328460015814 100319475328460015814 Yes Department of Biology, Gorgan Branch, Islamic Azad University, Gorgan, Iran. Hamideh Askari hamide_askari_z@yahoo.com 100319475328460015815 100319475328460015815 No Department of Biology, Gorgan Branch, Islamic Azad University, Gorgan, Iran. Hamid Reza Pordeli h_pordeli@yahoo.com 100319475328460015816 100319475328460015816 No Department of Biology, Gorgan Branch, Islamic Azad University, Gorgan, Iran.