Harbarth Stephan, Sax Hugo, Uckay Ilker, Fankhauser Carolina, Agostinho Americo, Christenson Jan T, Renzi Gesuele, Schrenzel Jacques, Pittet Didier
Infection Control Program, University of Geneva Hospitals and Medical Schools, Geneva, Switzerland.
J Am Coll Surg. 2008 Nov;207(5):683-9. doi: 10.1016/j.jamcollsurg.2008.05.023. Epub 2008 Jun 30.
Legislative mandates and current guidelines for control of nosocomial transmission of methicillin-resistant Staphylococcus aureus (MRSA) recommend screening of patients at risk of MRSA carriage on hospital admission. Indiscriminate application of these guidelines can result in a large number of unnecessary screening tests.
This study was conducted to develop and validate a prediction model to define surgical patients at risk of previously unknown MRSA carriage on admission. We used data from two prospective studies to derivate and validate predictors of previously unknown MRSA carriage on admission, using logistic regression analysis.
A total of 13,262 patients (derivation cohort, 3,069; validation cohort, 10,193) were admitted to the surgery department and screened for MRSA. Prevalence of MRSA carriage at time of admission increased from 3.2% in 2003 to 5.1% in the period 2004 to 2006, with a majority of newly identified MRSA carriers (64%). Three independent factors were correlated with previously unknown MRSA carriage: recent antibiotic treatment (adjusted odds ratio [OR]: 4.5; p < 0.001), history of hospitalization (adjusted OR: 2.7; p = 0.03), and age older than 75 years (adjusted OR: 1.9; p = 0.048). A score (range 0 to 9 points) calculated from these variables was developed. Probability of previously unknown MRSA carriage was 5% (8 of 152) in patients with a low score (< 2 points), 11% (19 of 166) in those with an intermediate score (2 to 6 points), and 34% (30 of 87) in those with a high score (> or = 7 points). Limiting screening to patients with all 3 risk factors (21% and 26% of patients in the derivation and validation cohort, respectively) would have correctly identified 53% and 37% of MRSA carriers in both cohorts.
A predictive model using three easily retrievable determinants might help to better target surgical patients at risk of MRSA carriage on admission.
关于控制耐甲氧西林金黄色葡萄球菌（MRSA）医院内传播的立法要求和现行指南建议在患者入院时对有MRSA携带风险的患者进行筛查。不加区分地应用这些指南可能会导致大量不必要的筛查检测。
本研究旨在开发并验证一种预测模型，以确定入院时存在此前未知的MRSA携带风险的外科手术患者。我们使用两项前瞻性研究的数据，通过逻辑回归分析来推导并验证入院时此前未知的MRSA携带的预测因素。
共有13262例患者（推导队列3069例，验证队列10193例）入住外科并接受MRSA筛查。入院时MRSA携带率从2003年的3.2%增至2004年至2006年期间的5.1%，大多数新发现的MRSA携带者（64%）。三个独立因素与此前未知的MRSA携带相关：近期抗生素治疗（调整后的优势比[OR]：4.5；p<0.001）、住院史（调整后的OR：2.7；p = 0.03）以及年龄大于75岁（调整后的OR：1.9；p = 0.048）。根据这些变量计算出一个分数（范围为0至9分）。低分（<2分）患者中此前未知的MRSA携带概率为5%（152例中的8例），中等分数（2至6分）患者中为11%（166例中的19例），高分（≥7分）患者中为34%（87例中的30例）。将筛查限于具有所有3种风险因素的患者（分别占推导队列和验证队列患者的21%和26%），将能在两个队列中正确识别出53%和37%的MRSA携带者。
使用三个易于获取的决定因素的预测模型可能有助于更好地针对入院时存在MRSA携带风险的外科手术患者。
