Awake Prone Positioning in Moderate ARDS: A Case Report

Background: Legionella pneumophila is a rare but severe cause of community-acquired pneumonia and can lead to acute respiratory distress syndrome (ARDS). Awake prone positioning (APP) has been recognized as an effective adjunct for non-intubated patients with hypoxemic respiratory failure, primarily studied in coronavirus disease 2019 (COVID-19) and other ARDS etiologies. Its application in Legionella-associated ARDS remains poorly documented. Therefore, in this work, we present a case of Legionella-associated ARDS successfully managed with APP, high-flow nasal cannula (HFNC), non-invasive ventilation (NIV), levofloxacin, and corticosteroids. Case presentation: A 62-year-old male with multiple comorbidities, including type 2 diabetes mellitus (T2DM) and a history of coronary artery bypass surgery, presented with a 3-day history of productive cough, exertional dyspnea, and general malaise. Oxygen saturation on admission was 90%, with fever and tachycardia. Inflammatory markers were markedly elevated. Chest computed tomography (CT) revealed extensive bilateral pulmonary infiltrates. Despite a negative urinary Legionella antigen test, sputum polymerase chain reaction (PCR) confirmed Legionella pneumophila on day 2. A Horowitz index of 147 mmHg on day 2 established moderate ARDS. The patient was treated with HFNC oxygen therapy, NIV, and APP for up to 12 h daily. Antibiotic therapy was initiated with amoxicillin/clavulanic acid and clarithromycin, subsequently streamlined to levofloxacin upon microbiological confirmation. Methylprednisolone 40 mg/day was administered for 8 days as adjunctive ARDS therapy. The patient demonstrated gradual clinical and respiratory improvement without requiring endotracheal intubation. Follow-up chest CT on day 7 showed regression of bilateral consolidations and ground-glass opacities (GGOs). The patient was transferred to pulmonary rehabilitation on day 11 and completed antibiotic therapy as an outpatient. Conclusions: This case illustrates the successful use of APP combined with HFNC and NIV alongside standard medical therapies, including appropriate antibiotics and corticosteroids, to avoid intubation in moderate ARDS secondary to Legionella pneumonia. Early initiation of APP may be a valuable strategy in Legionella-associated ARDS in carefully selected patients.