Achiam Cimi C, Fernandes Christopher Mahendra Bernard, McLeod Shelley L, Salvadori Marina I, John Michael, Seabrook Jamie A, Theakston Karl D, Milburn Susan, Hussain Zafar
aDivision of Emergency Medicine, Schulich School of Medicine and Dentistry bDepartment of Pediatrics and Sociology, Children's Health Research Institute, The University of Western Ontario cDepartment of Pediatrics dDepartment Pathology, Medical Microbiology, Schulich School Medicine and Dentistry, The University of Western Ontario eClinical Microbiology and Infection Control, London Health Sciences Center, London, Ontario, Canada.
Eur J Emerg Med. 2011 Feb;18(1):2-8. doi: 10.1097/MEJ.0b013e328337901a.
This study aimed to estimate the city-wide prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in patients (≥18 years old) presenting with skin and soft tissue infections (SSTIs) to the emergency departments (EDs) of a Canadian Academic Health Care Center. Secondary objectives were to identify demographic and clinical variables associated with MRSA, and determine MRSA antimicrobial susceptibilities and genotypes.
This prospective observational study was conducted over 2 months. Participants completed a Health and Lifestyle Questionnaire. Cultures of the infection site, nares, and throat were obtained and MRSA isolates were confirmed by polymerase chain reaction. Patient characteristics were summarized using descriptive statistics and MRSA prevalence and 95% confidence intervals were estimated using standard equations. Backwards stepwise multivariate logistic regression models determined predictor variables independently associated with MRSA colonization or infection.
Of 205 patients, 35 (17.1%) were infected or colonized with MRSA. Seventy-eight (38.0%) of the infection site cultures grew S. aureus of which 27 (34.6%) were MRSA. Incarceration, known exposure to MRSA and involvement in competitive sports were significant predictors of MRSA SSTIs. Antimicrobial susceptibility among MRSA isolates was trimethoprim/sulfamethoxazole, vancomycin, gentamicin, and linezolid 100%, clindamycin 75%, ciprofloxacin 59.3%, and erythromycin 7.4%. Sixty-nine percent of MRSA cases fit the clinical definition of community associated; subsequently 77% were confirmed as CMRSA 10, a recognized community-acquired MRSA.
Community-acquired -MRSA is a significant pathogen of SSTIs in EDs of a Canadian teaching center. MRSA should be considered when initiating empiric antibiotic therapy, particularly in patients with risk factors.
本研究旨在估计在加拿大一所学术医疗中心急诊科就诊的（≥18岁）皮肤和软组织感染（SSTIs）患者中耐甲氧西林金黄色葡萄球菌（MRSA）的全市患病率。次要目的是确定与MRSA相关的人口统计学和临床变量，并确定MRSA的抗菌药敏性和基因型。
这项前瞻性观察性研究持续了2个月。参与者完成了一份健康与生活方式问卷。获取感染部位、鼻腔和咽喉的培养物，并用聚合酶链反应确认MRSA分离株。使用描述性统计总结患者特征，并使用标准方程估计MRSA患病率和95%置信区间。向后逐步多变量逻辑回归模型确定与MRSA定植或感染独立相关的预测变量。
在205名患者中，35名（17.1%）感染或定植了MRSA。78份（38.0%）感染部位培养物培养出金黄色葡萄球菌，其中27份（34.6%）为MRSA。监禁、已知接触过MRSA以及参与竞技运动是MRSA SSTIs的重要预测因素。MRSA分离株的抗菌药敏性为：甲氧苄啶/磺胺甲恶唑、万古霉素、庆大霉素和利奈唑胺为100%，克林霉素为75%，环丙沙星为59.3%，红霉素为7.4%。69%的MRSA病例符合社区获得性的临床定义；随后77%被确认为CMRSA 10，一种公认的社区获得性MRSA。
社区获得性MRSA是加拿大教学中心急诊科SSTIs的重要病原体。在开始经验性抗生素治疗时应考虑MRSA，尤其是有危险因素的患者。
