主动监测培养气管中MRSA预测ICU患者后续MRSA感染

Active surveillance culture of the trachea for MRSA is predictor of MRSA infections among patients in Intensive Care Unit

目的：探讨主动监测培养鼻前庭或气管耐甲氧西林金黄色葡萄球菌（ methicillin－resistant staphylococcus aureus， MRSA）对于重症加强护理病房（ ICU）患者后续MRSA感染的敏感度和预测价值。方法对本院ICU收治的142例患者进行前瞻性研究，在入组患者刚入院和入院48 h取MRSA标本检测，之后每周检测1次。所有受试者在ICU期间常规监测MRSA感染情况。结果研究过程中发现65例（46％）患者MRSA定植。 MRSA在气管吸出物（82％，53／65）监测培养敏感度高于鼻前庭（47％，30／65）（P＜0．001）。气管中（分别为69％和93％）监测培养物预测MRSA感染和肺炎敏感度高于鼻前庭（分别为48％和50％）。预测后续MRSA感染的ROC曲线下面积值气管吸出物（0．675）高于鼻前庭（0．648），但差异没有统计学意义（P＞0．05）。 ROC曲线下面积值（MRSA肺炎）气管吸出物（0．791，95％CI 0．739～0．837）明显高于鼻前庭（0．649，95％CI 0．590～0．705）（P＝0．044）。结论相比鼻前庭，ICU患者主动监测培养气管吸出物MRSA预测后续MRSA肺炎更敏感。

Objective To investigate whether traditional surveillance culture of the anterior nares for methicillin-resistant staphylococcus aureus （ MRSA） shows sufficient sensitivity and predictive value compared to other sites, especially the trachea, in ICU patients.Methods A prospective observational cohort study was performed in 142 patients.Samples for MRSA detection were obtained at the time of admission, 48 h after admission, and then weekly thereafter.All subjects were routinely monitored for the development of MRSA infection during their stay in the ICU.Results MRSA colonization was detected in 65 （46%） patients over the course of the study.The sensitivity of MRSA surveillance culture was significantly higher in tracheal aspirates （ 82%, 53/65 ） than in anterior nares （47%, 30/65） （ P 〈0.001）.The sensitivity of MRSA surveillance culture for subsequent MRSA infection and MRSA pneumonia was also higher in the trachea （69% and 93%, respectively） than in the anterior nares （48 and 50%, respectively）.The area under the curve for subsequent MRSA infection was higher in trachea （0.675） than in the anterior nares （0.648）; however, this difference was not significant （P〉0.05）.The area under the curve for MRSA pneumonia was significantly higher in trachea （0.791, 95%CI 0.739 ~0.837） than anterior nares （0.649, 95% CI 0.590 ~0.705） （P=0.044）.Conclusion Cultures from tracheal aspirates are more sensitive and predictive of subsequent MRSA pneumonia than cultures from the anterior nares in this population.