Department of Medicine, University of Massachusetts Medical School-Baystate, Springfield, MA.
Department of Medicine, University of Massachusetts Medical School-Baystate, Springfield, MA; Institute for Healthcare Delivery and Population Science and Department of Medicine, University of Massachusetts Medical School-Baystate, Springfield, MA.
Chest. 2021 May;159(5):1782-1792. doi: 10.1016/j.chest.2020.12.013. Epub 2020 Dec 19.
American Thoracic Society/Infectious Diseases Society of America guidelines recommend against routine Legionella pneumophila testing, but recommend that hospitalized patients with community-acquired pneumonia receive empiric treatment covering Legionella. Testing, empiric treatment, and outcomes for patients with Legionella have not been well described.
Is testing for Legionella pneumophila appropriate, and could it impact treatment?
We conducted a large retrospective cohort analysis using Premier Healthcare Database data from 2010 to 2015. We included adults with a principal diagnosis code for pneumonia (or a principal diagnosis of respiratory failure or sepsis with secondary diagnosis of pneumonia) if they also received treatment for pneumonia on hospital days 1-3. We categorized Legionella-tested patients by test result, identified patient characteristics associated with testing and test result, and examined seasonal and regional patterns of Legionella pneumonia (LP) diagnoses. Empiric therapy for LP was defined as a macrolide, quinolone, or doxycycline, administered on each of the first two hospital days.
Of 166,689 eligible patients, 43,070 (26%) were tested for Legionella, and 642 (1.5%) tested positive. Although only 36% of tests were ordered from June to October, 70% of positive test results occurred during this time. Only 30% of patients with hyponatremia, 32% with diarrhea, and 27% in the ICU were tested. Of patients with positive test results, 495 of 642 (77%) had received empiric Legionella therapy. Patients with LP did not have more severe presentation. They had more frequent late decompensation, but similar mortality to patients without LP.
Legionella is an uncommon cause of community-acquired pneumonia, occurring primarily from late spring through early autumn. Testing is uncommon, even among patients with risk factors, and many patients with positive test results failed to receive empiric coverage for LP.
美国胸科学会/传染病学会指南建议避免常规检测嗜肺军团菌，但建议患有社区获得性肺炎的住院患者接受经验性治疗，覆盖军团菌。尚未很好地描述军团菌患者的检测、经验性治疗和结果。
检测嗜肺军团菌是否合适，是否会影响治疗？
我们使用 Premier Healthcare Database 数据库，对 2010 年至 2015 年的数据进行了一项大型回顾性队列分析。如果患者在住院第 1-3 天接受了肺炎的主要治疗（或呼吸衰竭或败血症的主要诊断，伴有肺炎的次要诊断），则将其纳入研究。我们根据检测结果对军团菌检测患者进行分类，确定与检测和检测结果相关的患者特征，并检查军团菌肺炎（LP）诊断的季节性和区域性模式。LP 的经验性治疗定义为大环内酯类、喹诺酮类或多西环素，在住院的前 2 天每天给药。
在 166689 名符合条件的患者中，有 43070 人（26%）接受了军团菌检测，642 人（1.5%）检测结果阳性。尽管只有 36%的检测是在 6 月至 10 月进行的，但 70%的阳性检测结果发生在这段时间内。只有 30%低钠血症、32%腹泻和 27%入住 ICU 的患者接受了检测。在检测结果阳性的患者中，642 例中有 495 例（77%）接受了 LP 的经验性治疗。LP 患者的表现没有更严重。他们更频繁地出现晚期失代偿，但死亡率与无 LP 患者相似。
嗜肺军团菌是社区获得性肺炎的一种罕见病因，主要发生在春末至初秋。检测并不常见，即使是在有危险因素的患者中，许多检测结果阳性的患者也未能接受 LP 的经验性治疗。
