Departments of Medical Microbiology ,Postgraduate Institute of Medical Education & Research, Chandigarh, India.
Indian J Med Res. 2009 Dec;130(6):742-8.
BACKGROUND & OBJECTIVE: Community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) is a major global problem. Colonization rates of MRSA in the community have been reported to range from 0 to 9.2 per cent. The present study was conducted to detect S. aureus nasal colonization and prevalence of MRSA in children (5 to 15 yr) in an Indian community setting of rural, urban and semiurban slums, as also evaluation of an in-house PCR to detect MRSA.
Nasal swabs from children were cultured and S. aureus isolates were processed for antibiotic susceptibility. mecA gene was studied by polymerase chain reaction (PCR) on S. aureus isolates and directly from enrichment broth aliquots inoculated with nasal swabs, at sequential time intervals.
The overall prevalence of S. aureus nasal colonization was 52.3 per cent and that of MRSA 3.89 per cent. CA-MRSA nasal carriage was 3.16 per cent in children without prior exposure to health care settings. PCR detection directly on nasal swabs and enrichment broth had a poor sensitivity of 60.42 per cent.
INTERPRETATION & CONCLUSION: There was a high rate of S. aureus nasal colonization in the 5-15 yr age group and an alarming rate (3.89%) of community acquired methicillin resistant S. aureus nasal colonization in the community. PCR as a method of direct detection of MRSA from nasal samples needs further fine tuning.
社区获得性耐甲氧西林金黄色葡萄球菌（CA-MRSA）是一个全球性的主要问题。社区中 MRSA 的定植率据报道为 0 至 9.2%。本研究旨在检测印度农村、城市和半城市贫民窟社区中儿童（5 至 15 岁）的金黄色葡萄球菌鼻腔定植和 MRSA 流行率，并评估一种用于检测 MRSA 的内部 PCR。
从儿童的鼻腔拭子中培养金黄色葡萄球菌分离株，并对其进行抗生素敏感性检测。通过聚合酶链反应（PCR）检测金黄色葡萄球菌分离株和直接从鼻腔拭子接种的富集肉汤等分试样中的 mecA 基因，在不同时间间隔进行。
金黄色葡萄球菌鼻腔定植的总体流行率为 52.3%，MRSA 的流行率为 3.89%。无先前接触医疗保健环境的儿童中，CA-MRSA 鼻腔携带率为 3.16%。直接在鼻腔拭子和富集肉汤上进行 PCR 检测的敏感性较差，为 60.42%。
5 至 15 岁年龄组中金黄色葡萄球菌鼻腔定植率较高，社区中获得性耐甲氧西林金黄色葡萄球菌鼻腔定植率（3.89%）令人震惊。作为从鼻腔样本中直接检测 MRSA 的方法，PCR 需要进一步优化。
