Healthcare Associated Infection and Antimicrobial Resistance Department, Health Protection Agency, London, UK.
J Hosp Infect. 2011 Nov;79(3):211-7. doi: 10.1016/j.jhin.2011.05.013. Epub 2011 Jul 20.
The national mandatory surveillance system for reporting meticillin-resistant Staphylococcus aureus (MRSA) bacteraemia in England has captured data on the source of reported bacteraemias since 2006. This study analysed episodes of MRSA bacteraemia (N=4404) where a probable source of infection was reported between 2006 and 2009. In 2009, this information was available for one-third of reported episodes of MRSA bacteraemia. Of these, 20% were attributed to intravascular devices and 28% were attributed to skin and soft tissue infection. Sixty-four percent of the patients were male, and urinary tract infection was a significantly more common source of MRSA bacteraemia in males compared with females (12% vs 3%). Detection of bacteraemia within two days of hospital admission does not reliably discriminate between community- and hospital-associated MRSA bacteraemia as community cases are frequently associated with an invasive procedure/device. Between 2006 and 2009, there was a significant decline in the proportion of episodes of MRSA bacteraemia associated with central vascular catheters [incidence rate ratio (IRR) 0.42, 95% confidence interval (CI) 0.29-0.61; P<0.001], peripheral vascular catheters (IRR 0.69, 95% CI 0.48-0.99; P=0.042) and surgical site infection (IRR 0.42, 95% CI 0.25-0.72; P=0.001), and a significant increase in the proportion of episodes of MRSA bacteraemia associated with skin and soft tissue infection (IRR 1.33, 95% CI 1.05-1.69; P=0.017) and attributed to contamination of the specimen (IRR 1.96, 95% CI 1.25-3.06; P=0.003). Since data were not available for all cases, the generalizability of these trends depends on the assumption that records with source data reflect a reasonably random sample of cases in each year. These changes have occurred in the context of a general decline in the rate of MRSA bacteraemia in England since 2006.
英格兰的耐甲氧西林金黄色葡萄球菌（MRSA）菌血症国家强制监测系统自 2006 年以来一直报告菌血症的来源数据。本研究分析了 2006 年至 2009 年间报告的 4404 例 MRSA 菌血症病例，其中报告了可能的感染源。2009 年，三分之一的 MRSA 菌血症病例可获得这些信息。其中，20%归因于血管内装置，28%归因于皮肤和软组织感染。64%的患者为男性，与女性相比，男性尿路感染是 MRSA 菌血症更常见的来源（12%对 3%）。菌血症在入院后两天内检出并不能可靠地区分社区和医院相关的 MRSA 菌血症，因为社区病例常与侵入性操作/装置有关。2006 年至 2009 年间，与中央血管导管相关的 MRSA 菌血症病例比例显著下降[发病率比（IRR）0.42，95%置信区间（CI）0.29-0.61；P<0.001]，外周血管导管（IRR 0.69，95%CI 0.48-0.99；P=0.042）和手术部位感染（IRR 0.42，95%CI 0.25-0.72；P=0.001），与皮肤和软组织感染相关的 MRSA 菌血症病例比例显著增加（IRR 1.33，95%CI 1.05-1.69；P=0.017），且归因于标本污染（IRR 1.96，95%CI 1.25-3.06；P=0.003）。由于并非所有病例都有数据，这些趋势的推广性取决于以下假设，即具有源数据的记录反映了每年病例的一个合理随机样本。自 2006 年以来，英格兰的 MRSA 菌血症率普遍下降，这些变化正是在此背景下发生的。
