Department of Infectious Diseases, St. Luke's International Hospital, Tokyo, Japan.
Department of Pulmonary Medicine, St. Luke's International Hospital, Tokyo, Japan.
Am J Case Rep. 2022 Jul 12;23:e936309. doi: 10.12659/AJCR.936309.
BACKGROUND We report a case of diffuse alveolar hemorrhage (DAH) caused by Legionella pneumophila serogroup (SG) 1 and review the existing literature to identify risk factors and determine the prognosis of patients with Legionella pneumonia-associated DAH. CASE REPORT A 44-year-old woman was admitted to our hospital following the presentation of dyspnea for a few days. Chest computed tomography (CT) findings revealed "crazy-paving" pattern in the right upper lobe implicating DAH and consolidation in the lower lobe. Analysis of the bronchoalveolar lavage (BAL) fluid revealed DAH, with further analyses identifying L. pneumophila SG 1 as the causative agent. The patient was successfully treated with levofloxacin and a red blood cell transfusion and discharged on the 32nd day of hospitalization. A literature review of 6 reported cases (including our case) of Legionella pneumonia-associated DAH revealed that the median age of patients with DAH was 59 years (range, 44-75 years), involving female patients in 4 cases (67%) and the use of immunosuppressive drugs in 2 cases (33%). Three cases were BAL Legionella polymerase chain reaction (PCR)-positive and 4 cases were diagnosed using a urinary Legionella antigen test (one case was simultaneously PCR-positive). These infections were caused by L. pneumophila SG 1 in three cases and SG 3 in one case. Mechanical ventilation was used in 5 cases (83%) and one patient had an unfavorable prognosis. Steroids for DAH were used in 5 cases (83%), and 2 cases responded to this treatment. CONCLUSIONS Our case highlights that clinicians should be aware of Legionella spp. as a cause of DAH in an immunocompetent host with "crazy-paving" pattern on chest CT, and perform a urinary antigen test and BAL PCR for diagnosis.
我们报告了一例由嗜肺军团菌血清群（SG）1 引起的弥漫性肺泡出血（DAH）病例，并回顾了现有文献，以确定军团菌肺炎相关 DAH 的危险因素和患者预后。
一名 44 岁女性因出现数日呼吸困难而被收入我院。胸部计算机断层扫描（CT）结果显示右上叶“铺路石”样改变提示 DAH，下叶实变。支气管肺泡灌洗液（BAL）分析显示 DAH，并进一步分析确定为嗜肺军团菌 SG 1 引起。该患者经左氧氟沙星和红细胞输注治疗后成功，于住院第 32 天出院。对 6 例（包括本病例）军团菌肺炎相关 DAH 报道病例的文献回顾发现，DAH 患者的中位年龄为 59 岁（范围，44-75 岁），涉及女性 4 例（67%），使用免疫抑制剂 2 例（33%）。3 例 BAL 军团菌聚合酶链反应（PCR）阳性，4 例通过尿军团菌抗原检测诊断（1 例同时 PCR 阳性）。这 3 例感染由嗜肺军团菌 SG 1 引起，1 例由 SG 3 引起。5 例（83%）使用机械通气，1 例患者预后不良。5 例（83%）使用 DAH 类固醇，2 例对此治疗有反应。
本病例强调了临床医生应意识到军团菌属是免疫功能正常宿主胸部 CT 出现“铺路石”样改变时 DAH 的病因之一，并进行尿抗原检测和 BAL PCR 以明确诊断。
