1Infectious Diseases and Tropical Medicine Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
2Department of Otorhinolaryngology, Loghman Hospital, Shahid-Beheshti University of Medical Sciences, Tehran, Iran.
Acta Microbiol Immunol Hung. 2023 Sep 18;70(3):231-238. doi: 10.1556/030.2023.02081. Print 2023 Sep 21.
Increase in antibiotic resistance in Staphylococcus aureus isolated from ear infection is a serious public health problem. The objective of this investigation was to determine the antibacterial resistance profile and genetic variability of the S. aureus isolated from adult patients with otitis externa (OE) and otitis media (OM) infections, Tehran- Iran. The disk diffusion was employed to detect the susceptibility of 45 S. aureus strains. Biofilm production was evaluated by microtiter plate assay. Genetic diversity of the isolates was determined by staphylococcal cassette SCCmec, spa, and MLST techniques. Resistance to mupirocin and vancomycin were identified in 40 and 2.2% of isolates. Out of the 45 S. aureus isolates, 41 (91.2%) strains were considered as positive biofilm strains at different levels. According to our results, S. aureus isolated from OM (44.4%, 20/45) were including CC8/ST239-SCCmecIII corresponded to spa types t860, t030, t037, t234, t421 (70%, 14/20) and CC/ST30-SCCmecIV corresponded to spa types t605 and t019 (30%, 6/20) while S. aureus isolated from OE (55.6%, 25/45) were including CC/ST30-SCCmecIV corresponded to spa types t605, t345 and t1130 (52%, 13/25), CC/ST22-SCCmecIV corresponded to spa type t790 (20%, 5/25), CC8/ST8-SCCmecIV corresponded to spa type t008 (16%, 4/25), and CC/ST45-SCCmecIV corresponded to spa types t004 and t038 (12%, 3/25). This study highlighted genetic variability and strong biofilm formation ability among our isolates revealing its crucial role in enhancing the resistance of this bacteria to drugs. Thus, it is necessary to continue the epidemiological analysis to improve the control of ear infections related to S. aureus.
金黄色葡萄球菌（Staphylococcus aureus）引起的耳部感染中抗生素耐药性的增加是一个严重的公共卫生问题。本研究的目的是确定从伊朗德黑兰患有外耳炎（otitis externa，OE）和中耳炎（otitis media，OM）感染的成年患者中分离出的金黄色葡萄球菌的抗菌药物耐药谱和遗传变异性。采用纸片扩散法检测 45 株金黄色葡萄球菌的药敏性。采用微量滴定板法评估生物膜的产生。采用葡萄球菌盒式染色体 SCCmec、spa 和 MLST 技术确定分离株的遗传多样性。40%和 2.2%的分离株对莫匹罗星和万古霉素耐药。在 45 株金黄色葡萄球菌中，41 株（91.2%）菌株在不同水平上被认为是阳性生物膜菌株。根据我们的结果，从 OM 中分离的金黄色葡萄球菌（44.4%，20/45）包括 CC8/ST239-SCCmecIII，对应的 spa 类型为 t860、t030、t037、t234 和 t421（70%，14/20）和 CC/ST30-SCCmecIV，对应的 spa 类型为 t605 和 t019（30%，6/20），而从 OE 中分离的金黄色葡萄球菌（55.6%，25/45）包括 CC/ST30-SCCmecIV，对应的 spa 类型为 t605、t345 和 t1130（52%，13/25），CC/ST22-SCCmecIV，对应的 spa 类型为 t790（20%，5/25），CC8/ST8-SCCmecIV，对应的 spa 类型为 t008（16%，4/25）和 CC/ST45-SCCmecIV，对应的 spa 类型为 t004 和 t038（12%，3/25）。本研究强调了我们分离株的遗传变异性和强生物膜形成能力，这表明其在增强该细菌对药物的耐药性方面发挥着重要作用。因此，有必要继续进行流行病学分析，以改善金黄色葡萄球菌相关耳部感染的控制。
