From the Division of Trauma, Emergency Surgery and Critical Care (G.M.V.D.W., C.C., M.S., D.D.Y., D.R.K., M.A.D.M., P.J.F., G.C.V.), Department of Surgery, and Division of Biostatistics (Y.C.), Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Department of Trauma Surgery (G.M.V.D.W., I.B.S.), Leiden University Medical Center and Leiden University, Leiden, the Netherlands.
J Trauma Acute Care Surg. 2014 Feb;76(2):424-30. doi: 10.1097/TA.0000000000000105.
Of the patients with a Clostridium difficile infection, 2% to 8% will progress to fulminant C. difficile colitis (fCDC), which carries high morbidity and mortality. No system exists to rapidly identify patients at risk for developing fCDC and possibly in need of surgical intervention. Our aim was to design a simple and accurate risk scoring system (RSS) for daily clinical practice.
We prospectively enrolled all patients diagnosed with a C. difficile infection and compared patients with and without fCDC. An expert panel, combined with data derived from previous studies, identified four risk factors, and a multivariable logistic regression model was performed to determine their effect in predicting fCDC. The RSS was created based on the predictive power of each factor, and calibration, discrimination, and test characteristics were subsequently determined. In addition, the RSS was compared with a previously proposed severity scoring system.
A total of 746 patients diagnosed with C. difficile infection were enrolled between November 2010 and October 2012. Based on the log (odds ratio) of each risk factor, age greater than 70 years was assigned 2 points, white blood cell count equal to or greater than 20,000/μL or equal to or less than 2,000/μL was assigned 1 point, cardiorespiratory failure was assigned 7 points, and diffuse abdominal tenderness on physical examination was assigned 6 points. With the use of this system, the discriminatory value of the RSS (c statistic) was 0.98 (95% confidence interval, 0.96-1).The Hosmer-Lemeshow goodness-of-fit test showed a p value of 0.78, and the Brier score was 0.019. A value of 6 points was determined to be the threshold for reliably dividing low-risk ( <6) from high-risk (≥ 6) patients.
The RSS is a valid and reliable tool to identify at the bedside patients who are at risk for developing fCDC. External validation is needed before widespread implementation.
Prognostic study, level II.
在艰难梭菌感染患者中,有 2%至 8%会发展为暴发性艰难梭菌结肠炎(fulminant C. difficile colitis,fCDC),其发病率和死亡率都很高。目前尚无系统能够快速识别出有发展为 fCDC 风险的患者,从而可能需要进行手术干预。我们的目的是设计一种简单而准确的风险评分系统(risk scoring system,RSS),以便于在日常临床实践中使用。
我们前瞻性地纳入所有诊断为艰难梭菌感染的患者,并比较了发生和未发生 fCDC 的患者。一个专家小组结合来自先前研究的数据,确定了四个风险因素,并进行了多变量逻辑回归模型分析,以确定这些因素对预测 fCDC 的影响。根据每个因素的预测能力创建 RSS,并随后确定其校准、区分度和检测特征。此外,还将 RSS 与先前提出的严重程度评分系统进行了比较。
2010 年 11 月至 2012 年 10 月期间,共纳入了 746 例诊断为艰难梭菌感染的患者。根据每个风险因素的对数(优势比),年龄大于 70 岁赋值 2 分,白细胞计数等于或大于 20,000/μL 或等于或小于 2,000/μL 赋值 1 分,心肺功能衰竭赋值 7 分,体检时弥漫性腹部压痛赋值 6 分。使用该系统,RSS 的区分度(c 统计量)为 0.98(95%置信区间,0.96-1)。Hosmer-Lemeshow 拟合优度检验 p 值为 0.78,Brier 评分 0.019。确定 6 分作为区分低危(<6)和高危(≥6)患者的可靠阈值。
RSS 是一种有效的床边工具,可用于识别有发生 fCDC 风险的患者。在广泛应用之前,需要进行外部验证。
预后研究,Ⅱ级。