Rupasinghe Sawandika, Lemoh Christopher
Footscray Hospital, Western Health, Footscray, Australia.
Postgraduate Institute of Medicine, University of Colombo, Colombo, Sri Lanka.
J Med Case Rep. 2025 Jul 13;19(1):341. doi: 10.1186/s13256-025-05407-8.
Legionella pneumophila is a bacterium found in natural water sources and artificial water systems. The most widely reported manifestation of Legionella infection is pneumonia, which is also known as Legionnaires' disease. Legionnaires' disease is typically spread through inhalation of aerosolized water droplets containing Legionella bacteria. This usually manifests with cough, fever, shortness of breath, and gastrointestinal disturbances. Legionella infection is known to cause a variety of extrapulmonary complications, including acute kidney injury, rhabdomyolysis, cardiac complications, liver involvement, and electrolyte imbalances. Acute kidney injury in Legionella disease is due to the cytotoxic effects of bacteria that directly invade renal tubular epithelial cells, the immune response triggered by bacteria that leads to systemic inflammation, thereby compromising renal perfusion and microthelial dysfunction, which reduces the blood flow of kidneys, causing hypoperfusion. Indirect causes for acute kidney injury include dehydration and nephrotoxic medication. Acute kidney injury in patients with Legionella pneumonia is oliguric but reversible with antibiotic treatment. Diagnosis of Legionella disease is through a combination of clinical assessment, laboratory tests, and imaging. Legionella urinary antigen testing and polymerase chain reaction confirms the diagnosis. Treatment of choice is antibiotics along with symptomatic management.
We report three cases of Legionnaires' disease from a tertiary care hospital in Australia that were complicated with severe acute kidney injury requiring continuous renal replacement therapy. All three patients were middle aged immunocompetent males; two were Australian and one was Macedonian. Case 1 was associated with acute kidney injury, hyponatremia, rhabdomyolysis, delirium, and liver impairment. The patient in case 2 developed acute kidney injury, rapid atrial fibrillation, type 2 non-ST elevation myocardial infarction, and liver function derangement. Case 3 was associated with acute kidney injury, rhabdomyolysis, and subdural hemorrhage secondary to fall. All our patients were treated with intravenous antibiotics, supplemental oxygen therapy, and continuous renal replacement therapy, after which they achieved complete recovery.
Legionella infection can lead to serious extrapulmonary complications, including acute kidney injury, rhabdomyolysis, cardiac, and liver involvement. Timely diagnosis and prompt management are important in addressing both the infection and its extrapulmonary complications.
嗜肺军团菌是一种存在于天然水源和人工水系统中的细菌。军团菌感染最广泛报道的表现形式是肺炎，也被称为军团病。军团病通常通过吸入含有军团菌的雾化水滴传播。其通常表现为咳嗽、发热、呼吸急促和胃肠道紊乱。已知军团菌感染会引起多种肺外并发症，包括急性肾损伤、横纹肌溶解、心脏并发症、肝脏受累和电解质失衡。军团病中的急性肾损伤是由于细菌直接侵袭肾小管上皮细胞的细胞毒性作用，细菌引发的免疫反应导致全身炎症，从而损害肾灌注和微血管功能障碍，减少肾脏血流，导致灌注不足。急性肾损伤的间接原因包括脱水和肾毒性药物。军团菌肺炎患者的急性肾损伤是少尿型的，但通过抗生素治疗可逆转。军团病的诊断通过临床评估、实验室检查和影像学检查相结合来进行。军团菌尿抗原检测和聚合酶链反应可确诊。治疗的选择是使用抗生素并进行对症处理。
我们报告了澳大利亚一家三级护理医院的三例军团病病例，这些病例并发了严重的急性肾损伤，需要持续肾脏替代治疗。所有三名患者均为中年免疫功能正常男性；两名是澳大利亚人，一名是马其顿人。病例1伴有急性肾损伤、低钠血症、横纹肌溶解、谵妄和肝功能损害。病例2的患者出现急性肾损伤伴快速心房颤动、2型非ST段抬高型心肌梗死和肝功能紊乱。病例3伴有急性肾损伤、横纹肌溶解以及跌倒后导致的硬膜下出血。我们所有的患者均接受了静脉抗生素治疗、补充氧气治疗和持续肾脏替代治疗，之后均实现了完全康复。
军团菌感染可导致严重的肺外并发症，包括急性肾损伤、横纹肌溶解、心脏和肝脏受累。及时诊断和迅速处理对于应对感染及其肺外并发症至关重要。
