Department of Infectious Diseases, Hospital Universitari de Bellvitge, IDIBELL (Institut Dinnvestigació Biomèdica de Bellvitge), Universitat de Barcelona, Barcelona, Spain.
PLoS One. 2013 Apr 16;8(4):e61036. doi: 10.1371/journal.pone.0061036. Print 2013.
It is not known whether rainfall increases the risk of sporadic cases of Legionella pneumonia. We sought to test this hypothesis in a prospective observational cohort study of non-immunosuppressed adults hospitalized for community-acquired pneumonia (1995-2011). Cases with Legionella pneumonia were compared with those with non-Legionella pneumonia. Using daily rainfall data obtained from the regional meteorological service we examined patterns of rainfall over the days prior to admission in each study group. Of 4168 patients, 231 (5.5%) had Legionella pneumonia. The diagnosis was based on one or more of the following: sputum (41 cases), antigenuria (206) and serology (98). Daily rainfall average was 0.556 liters/m(2) in the Legionella pneumonia group vs. 0.328 liters/m(2) for non-Legionella pneumonia cases (p = 0.04). A ROC curve was plotted to compare the incidence of Legionella pneumonia and the weighted median rainfall. The cut-off point was 0.42 (AUC 0.54). Patients who were admitted to hospital with a prior weighted median rainfall higher than 0.42 were more likely to have Legionella pneumonia (OR 1.35; 95% CI 1.02-1.78; p = .03). Spearman Rho correlations revealed a relationship between Legionella pneumonia and rainfall average during each two-week reporting period (0.14; p = 0.003). No relationship was found between rainfall average and non-Legionella pneumonia cases (-0.06; p = 0.24). As a conclusion, rainfall is a significant risk factor for sporadic Legionella pneumonia. Physicians should carefully consider Legionella pneumonia when selecting diagnostic tests and antimicrobial therapy for patients presenting with CAP after periods of rainfall.
尚不清楚降雨是否会增加散发性军团菌肺炎的风险。我们试图在一项针对因社区获得性肺炎住院的非免疫抑制成年患者的前瞻性观察队列研究中检验这一假说（1995-2011 年）。将军团菌肺炎病例与非军团菌肺炎病例进行比较。利用从区域气象部门获得的每日降雨数据，我们检查了每个研究组入院前几天的降雨模式。在 4168 例患者中，231 例（5.5%）患有军团菌肺炎。该诊断基于以下一项或多项检查：痰（41 例）、尿抗原（206 例）和血清学（98 例）。军团菌肺炎组的日平均降雨量为 0.556 升/平方米，而非军团菌肺炎组为 0.328 升/平方米（p=0.04）。绘制 ROC 曲线比较军团菌肺炎的发生率和加权中位数降雨量。截断值为 0.42（AUC 为 0.54）。入院前加权中位数降雨量高于 0.42 的患者更有可能患有军团菌肺炎（OR 为 1.35；95%CI 为 1.02-1.78；p=0.03）。Spearman Rho 相关性分析显示，军团菌肺炎与每两周报告期内的平均降雨量之间存在关系（0.14；p=0.003）。未发现平均降雨量与非军团菌肺炎病例之间存在关系（-0.06；p=0.24）。综上所述，降雨是散发性军团菌肺炎的一个重要危险因素。医生在为 CAP 患者选择诊断试验和抗菌治疗时，应在降雨后仔细考虑军团菌肺炎的可能性。
