Buising K L, Thursky K A, Black J F, MacGregor L, Street A C, Kennedy M P, Brown G V
Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville, Victoria 3050, Australia.
Thorax. 2006 May;61(5):419-24. doi: 10.1136/thx.2005.051326. Epub 2006 Jan 31.
Several severity scores have been proposed to predict patient outcome and to guide initial management of patients with community acquired pneumonia (CAP). Most have been derived as predictors of mortality. A study was undertaken to compare the predictive value of these tools using different clinically meaningful outcomes as constructs for "severe pneumonia".
A prospective cohort study was performed of all patients presenting to the emergency department with an admission diagnosis of CAP from March 2003 to March 2004. Clinical and laboratory features at presentation were used to calculate severity scores using the pneumonia severity index (PSI), the revised American Thoracic Society score (rATS), and the British Thoracic Society (BTS) severity scores CURB, modified BTS severity score, and CURB-65. The sensitivity, specificity, positive and negative predictive values were compared for four different outcomes (death, need for ICU admission, and combined outcomes of death and/or need for ventilatory or inotropic support).
392 patients were included in the analysis; 37 (9.4%) died and 26 (6.6%) required ventilatory and/or inotropic support. The modified BTS severity score performed best for all four outcomes. The PSI (classes IV+V) and CURB had a very similar performance as predictive tools for each outcome. The rATS identified the need for ICU admission well but not mortality. The CURB-65 score predicted mortality well but performed less well when requirement for ICU was included in the outcome of interest. When the combined outcome was evaluated (excluding patients aged >90 years and those from nursing homes), the best predictors were the modified BTS severity score (sensitivity 94.3%) and the PSI and CURB score (sensitivity 83.3% for both).
Different severity scores have different strengths and weaknesses as prediction tools. Validation should be done in the most relevant clinical setting, using more appropriate constructs of "severe pneumonia" to ensure that these potentially useful tools truly deliver what clinicians expect of them.
已提出多种严重程度评分系统来预测患者预后并指导社区获得性肺炎（CAP）患者的初始治疗。大多数评分系统是作为死亡率的预测指标推导出来的。本研究旨在比较这些工具以不同临床意义结局作为“重症肺炎”构成要素时的预测价值。
对2003年3月至2004年3月因CAP入院诊断而就诊于急诊科的所有患者进行前瞻性队列研究。使用肺炎严重程度指数（PSI）、修订后的美国胸科学会评分（rATS）以及英国胸科学会（BTS）严重程度评分CURB、改良BTS严重程度评分和CURB-65，根据就诊时的临床和实验室特征计算严重程度评分。比较四种不同结局（死亡、入住重症监护病房的需求以及死亡和/或呼吸或血管活性药物支持的联合结局）的敏感性、特异性、阳性预测值和阴性预测值。
392例患者纳入分析；37例（9.4%）死亡，26例（6.6%）需要呼吸和/或血管活性药物支持。改良BTS严重程度评分在所有四种结局中表现最佳。PSI（IV+V级）和CURB作为每种结局的预测工具表现非常相似。rATS能很好地识别入住重症监护病房的需求，但对死亡率的识别不佳。CURB-65评分对死亡率预测良好，但当将入住重症监护病房的需求纳入感兴趣的结局时表现较差。当评估联合结局时（排除年龄>90岁的患者和养老院患者），最佳预测指标是改良BTS严重程度评分（敏感性94.3%）以及PSI和CURB评分（两者敏感性均为83.3%）。
不同严重程度评分作为预测工具各有优缺点。应在最相关的临床环境中进行验证，使用更合适的“重症肺炎”构成要素，以确保这些潜在有用的工具真正达到临床医生对它们的期望。
