Department of Pulmonology, Noordwest Ziekenhuisgroep, Alkmaar, Netherlands.
Department of Pulmonology, Medisch Centrum Leeuwarden, Henri Dunantweg 2, 8934 AD, Leeuwarden, Netherlands.
BMC Infect Dis. 2022 May 9;22(1):442. doi: 10.1186/s12879-022-07433-z.
Legionella-related community acquired pneumonia (CAP) is a disease with an increasing incidence and a high mortality rate, especially if empirical antibiotic therapy is inadequate. Antibiotic treatment highly relies on clinical symptoms, although proven non-specific, because currently available diagnostic techniques provide insufficient accuracy for detecting Legionella CAP on admission. This study validates a diagnostic scoring system for detection of Legionella-related CAP, based on six items on admission (Legionella prediction score).
We included patients with Legionella-related CAP admitted to five large Dutch hospitals between 2006 and 2016. Controls were non-Legionella-related CAP patients. The following six conditions were rewarded one point if present: fever > 39.4 °C; dry cough; hyponatremia (sodium) < 133 mmol/L; lactate dehydrogenase (LDH) > 225 mmol/L; C-reactive protein (CRP) > 187 mg/L and platelet count < 171 × 10/L. The accuracy of the prediction score was assessed by calculating the area under the curve (AUC) through logistic regression analysis.
We included 131 cases and 160 controls. A score of 0 occurred in non-Legionella-related CAP patients only, a score of 5 and 6 in Legionella-related CAP patients only. A cut-off ≥ 4 resulted in a sensitivity of 58.8% and a specificity of 93.1%. The AUC was 0.89 (95% CI 0.86-0.93). The strongest predictors were elevated LDH, elevated CRP and hyponatremia.
This multi-centre study validates the Legionella prediction score, an easily applicable diagnostic scoring system, in a large group of patients and finds high diagnostic accuracy. The score shows promise for future prospective validation and could contribute to targeted antibiotic treatment of suspected Legionella CAP.
军团菌相关社区获得性肺炎（CAP）是一种发病率不断增加且死亡率较高的疾病，尤其是如果经验性抗生素治疗不充分的话。抗生素治疗高度依赖于临床症状，尽管这是一种未经证实的非特异性方法，因为目前可用的诊断技术对于入院时检测军团菌 CAP 的准确性不足。本研究验证了一种基于入院时 6 项指标的诊断评分系统（军团菌预测评分），用于检测军团菌相关 CAP。
我们纳入了 2006 年至 2016 年期间在五家荷兰大型医院住院的军团菌相关 CAP 患者。对照组为非军团菌相关 CAP 患者。如果存在以下六种情况，则各计 1 分：体温>39.4°C；干咳；低钠血症（钠）<133mmol/L；乳酸脱氢酶（LDH）>225mmol/L；C 反应蛋白（CRP）>187mg/L 和血小板计数<171×10/L。通过逻辑回归分析计算曲线下面积（AUC）评估预测评分的准确性。
我们纳入了 131 例病例和 160 例对照组。非军团菌相关 CAP 患者的评分均为 0，军团菌相关 CAP 患者的评分均为 5 或 6。截断值≥4 时，敏感性为 58.8%，特异性为 93.1%。AUC 为 0.89（95%CI 0.86-0.93）。最强的预测指标是 LDH、CRP 和低钠血症升高。
这项多中心研究在一大组患者中验证了军团菌预测评分，这是一种易于应用的诊断评分系统，具有较高的诊断准确性。该评分具有未来前瞻性验证的潜力，并可能有助于对疑似军团菌 CAP 的靶向抗生素治疗。
