Singh Seema, Malhotra Rubina, Grover Pragati, Bansal Renu, Galhotra Shipra, Kaur Rupinderjit, Jindal Neerja
Department of Microbiology, GGSMC, Faridkot, Punjab, India.
J Lab Physicians. 2017 Oct-Dec;9(4):317-321. doi: 10.4103/JLP.JLP_8_17.
Resistance to antimicrobial agents is a major concern worldwide and is exemplified by the global spread of the Methicillin resistant (MRSA). Health care workers (HCWs) and asymptomatically colonized patients are important sources of nosocomial MRSA infections.
To determine the prevalence of MRSA colonisation, two hundred HCWs and 200 consecutive outpatients attending our tertiary care hospital were studied.
Two sterile pre-moistened cotton tipped swabs were used to collect specimens from their anterior nares. These were inoculated immediately on Blood agar with oxacillin, Mannitol salt agar with oxacillin and CHROM agar. Resistance to cefoxitin was confirmed by PCR by demonstration of mecA gene. Antibiotic susceptibility was determined by Kirby Bauer's disc diffusion method and MIC of vancomycin by using broth dilution and Vitek-2 Compact system.
The nasal carriage of MRSA among HCWs was found to be 7.5% and in outpatients 3%. All strains of MRSA from HCWs and outpatients grew on three selective media and mecA gene amplified in all of them. All the isolated strains of MRSA showed high degree of resistance to co-trimoxazole (93.3%), ciprofloxacin (80%) and erythromycin (66.66%). However, there was 100% susceptiability to vancomycin, teicoplanin, linezolid and Rifampicin.
Although a direct casual relationship could not be established, it could be assumed that the transmission from colonised health care worker is responsible atleast in part for MRSA infection among patients. Therefore emphasis should be laid on strict implementation of standard infection control practices which would help in minimizing the carriage and transmission of MRSA in the hospital.
抗菌药物耐药性是全球主要关注的问题，耐甲氧西林金黄色葡萄球菌（MRSA）在全球的传播就是例证。医护人员（HCWs）和无症状定植患者是医院获得性MRSA感染的重要来源。
为确定MRSA定植的患病率，对200名医护人员和200名连续就诊于我们三级护理医院的门诊患者进行了研究。
使用两支无菌预湿棉拭子从前鼻孔采集标本。立即将这些标本接种在含苯唑西林的血琼脂、含苯唑西林的甘露醇盐琼脂和CHROM琼脂上。通过PCR检测mecA基因来确认对头孢西丁的耐药性。采用 Kirby Bauer 纸片扩散法测定抗生素敏感性，使用肉汤稀释法和Vitek-2 Compact系统测定万古霉素的最低抑菌浓度（MIC）。
医护人员中MRSA的鼻腔携带率为7.5%，门诊患者中为3%。来自医护人员和门诊患者的所有MRSA菌株均在三种选择性培养基上生长，且所有菌株的mecA基因均扩增成功。所有分离出的MRSA菌株对复方新诺明（93.3%）、环丙沙星（80%）和红霉素（66.66%）表现出高度耐药性。然而，对万古霉素、替考拉宁、利奈唑胺和利福平的敏感性为100%。
虽然无法建立直接的因果关系，但可以推测定植的医护人员传播至少部分导致了患者中的MRSA感染。因此，应强调严格实施标准感染控制措施，这将有助于减少医院中MRSA的携带和传播。
