■嗜肺军团菌可引起广泛的临床表现,从轻微的流感样疾病到暴发性多器官受累,以严重肺炎为特征,腹泻,脑病,震惊,肝功能障碍和肾功能衰竭。很少,它可能与血液学疾病有关,例如血栓性血小板减少性紫癜(TTP),溶血性尿毒综合征(HUS)和免疫性血小板减少性紫癜(ITP)。我们报告了一例罕见的导致ITP的嗜肺乳杆菌,并回顾了文献中先前发表的与军团菌病相关的血小板减少症病例。
■一名53岁的男性发烧,发冷,咳嗽和严重的咯血。血液工作对白细胞增多非常显著,严重的血小板减少和低钠血症。计算机断层扫描(CT)成像显示左下叶肺实变,外周血涂片显示巨大血小板与ITP一致。军团菌尿抗原检测呈阳性。他接受了静脉注射免疫球蛋白治疗,类固醇锥度和为期十天的阿奇霉素疗程,这导致他的血小板计数正常化和肺炎消退。
■L.嗜肺可导致补体介导的血小板破坏,导致ITP。针对嗜肺乳杆菌的抗体也可与酶ADAMTS13交叉反应,抑制其功能并导致TTP和HUS。此外,嗜肺乳杆菌可感染血管内皮细胞,导致其死亡并刺激vonWillebrand因子(vWF)多聚体释放到血液中,促进血栓形成和血小板消耗。
■对于任何出现肺炎和严重血小板减少症的患者,内科医生必须考虑不同的嗜肺乳杆菌。早期检测和干预可以导致预防严重出血和更好的结果。
结论:嗜肺军团菌很少与不同的血液系统疾病相关,导致严重的出血素质和血栓形成。对于任何出现肺炎和严重血小板减少症的患者,内科医生在鉴别诊断中考虑嗜肺军团菌很重要。早期检测和干预可以导致预防严重出血和更好的结果。
UNASSIGNED: Legionella pneumophila can cause a wide spectrum of clinical manifestations, ranging from a mild flu-like illness to fulminant multi-organ involvement, characterised by severe pneumonia, diarrhoea, encephalopathy, shock, hepatic dysfunction and renal failure. Very rarely, it can be associated with haematologic conditions such as thrombotic thrombocytopenic purpura (TTP), haemolytic uraemic syndrome (HUS) and immune thrombocytopenic purpura (ITP). We report a rare case of L. pneumophila causing ITP and review previously published cases of thrombocytopenia associated with Legionellosis in the literature.
UNASSIGNED: A 53-year-old male presented with fevers, chills, a productive cough and severe haemoptysis. Blood work was remarkable for leukocytosis, severe thrombocytopenia and hyponatraemia. Computed tomography (CT) imaging showed left lower lobe lung consolidation, and a peripheral blood smear showed giant platelets consistent with ITP. Legionella urine antigen testing returned positive. He was treated with intravenous immunoglobin, steroid taper and a ten-day course of azithromycin, which led to normalisation of his platelet count and resolution of the pneumonia.
UNASSIGNED: L. pneumophila can lead to complement-mediated destruction of platelets resulting in ITP. Antibodies against L. pneumophila can also cross-react with the enzyme ADAMTS13, inhibiting its function and resulting in TTP and HUS. Additionally, L. pneumophila can infect vascular endothelial cells causing their death and stimulating release of von Willebrand factor (vWF) multimers into the bloodstream, promoting thrombosis and platelet consumption.
UNASSIGNED: It is important for internists to consider L. pneumophila in the differential for any patient presenting with pneumonia and severe thrombocytopenia. Earlier detection and intervention can lead to prevention of critical bleeding and better outcomes.
CONCLUSIONS: Legionella pneumophila is rarely associated with different haematologic disorders resulting in severe bleeding diathesis as well as thrombosis.It is important for internists to consider Legionella pneumophila in the differential diagnosis for any patient presenting with pneumonia and severe thrombocytopenia.Earlier detection and intervention can lead to prevention of critical bleeding and better outcomes.