Fomda B A, Thokar M A, Khan A, Bhat J A, Zahoor D, Bashir G, Majid A, Ray P
Department of Microbiology, Sher i Kashmir Institute of Medical Sciences, Soura, Srinagar, Kashmir, India.
Indian J Med Microbiol. 2014 Jan-Mar;32(1):39-43. doi: 10.4103/0255-0857.124296.
Nasal colonisation with community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) is being increasingly reported, especially in places where people are in close contact and where hygiene is compromised. The aim of this study was to find out prevalence of methicillin resistant S.aureus (MRSA) colonising anterior nares of healthy subjects.
Nasal swabs of healthy subjects were collected aseptically and cultured using standard microbiological protocols. Antibiotic susceptibility was done by Kirby-Bauer disc diffusion method according to CLSI guidelines. Methicillin resistance was detected by cefoxitin disc diffusion method and confirmed by minimum inhibitory concentration (MIC) and amplification of mecA gene by PCR. Strain typing of MRSA strains was done by PFGE.
Out of 820 samples, S.aureus was isolated from 229 (27.92%) subjects. Of the 229 isolates, 15 were methicillin resistant. All S. aureus isolates were susceptible to vancomycin. Nasal carriage of MRSA was found to be 1.83% among healthy population. The isolates were found to be polyclonal by PFGE analysis.
High prevalence of MRSA is a cause of concern and strategies to interrupt transmission should be implemented.
社区获得性耐甲氧西林金黄色葡萄球菌(CA-MRSA)在鼻腔定植的报道日益增多,尤其是在人员密切接触且卫生条件较差的场所。本研究的目的是了解健康受试者前鼻孔耐甲氧西林金黄色葡萄球菌(MRSA)的定植率。
无菌采集健康受试者的鼻拭子,采用标准微生物学方案进行培养。根据临床和实验室标准协会(CLSI)指南,采用 Kirby-Bauer 纸片扩散法进行药敏试验。通过头孢西丁纸片扩散法检测耐甲氧西林情况,并通过最低抑菌浓度(MIC)和 PCR 扩增 mecA 基因进行确认。通过脉冲场凝胶电泳(PFGE)对 MRSA 菌株进行分型。
在 820 份样本中,从 229 名(27.92%)受试者中分离出金黄色葡萄球菌。在这 229 株分离株中,有 15 株耐甲氧西林。所有金黄色葡萄球菌分离株对万古霉素敏感。健康人群中 MRSA 的鼻腔携带率为 1.83%。通过 PFGE 分析发现这些分离株为多克隆。
MRSA 的高流行率令人担忧,应实施中断传播的策略。