C42-08 A Case of Daptomycin-associated Acute Eosinophilic Pneumonia Requiring Prolonged Steroid Treatment

Abstract Introduction Acute eosinophilic pneumonia(AEP) causes acute respiratory failure characterized by peripheral eosinophilia or eosinophilia on bronchoalveolar lavage or lung biopsy. Diagnostic criteria include acute febrile respiratory illness, diffuse pulmonary infiltrates, pulmonary eosinophilia, and absence of other infectious or eosinophilic pulmonary disease. AEP can be idiopathic or caused by inhalational exposures, leukemia, allergies, infections, or medications. Severe AEP can manifest as acute respiratory distress syndrome requiring corticosteroid treatment. Optimal steroid regimen is uncertain, though research suggests shorter courses are non-inferior. We present a rare case of suspected daptomycin-associated AEP requiring prolonged high-dose steroids. Case A 72-year-old man with peripheral artery disease presented with one day of fever(38.8C), hypotension, and new requirement of 2 liters nasal cannula(NC). He denied recent smoking, travel, radiation, or inhalational exposures. Two weeks prior, he started daptomycin for multidrug-resistant polymicrobial vascular graft infection. Linezolid was avoided given thrombocytopenia. This admission, E.Coli bacteremia was diagnosed and meropenem added. Despite adequate treatment, his fevers persisted and he was escalated to high-flow NC. Chest CT demonstrated bilateral multifocal opacities. Blood eosinophils peaked at 1.3K/μL. Repeat blood and sputum cultures, MRSA nares, respiratory viral panel, beta-D-glucan, Aspergillus galactomannan, and Blastomyces, Histoplasma, Legionella, and Streptococcus antigens were negative. Given hypoxemia, peripheral eosinophilia, lung opacities, unremarkable infectious work-up, and recent daptomycin exposure, we suspected daptomycin-associated AEP. We deferred bronchoscopy due to respiratory instability. We held daptomycin and initiated IV dexamethasone 20mg daily. After five days, eosinophilia resolved and oxygen was weaned down. Dexamethasone was tapered to 10mg daily and daptomycin reinitiated as the preferred agent for graft infection coverage. However, hypoxemia recurred after one day, requiring continuous bi-level positive airway pressure(BiPAP). Daptomycin was stopped. Dexamethasone 20mg daily was resumed for two days, after which he weaned off BiPAP. Dexamethasone taper was restarted (15mg x5 days, 10mg x5 days, 5mg x5 days) with clinical improvement. Graft infection treatment was completed with linezolid. He discharged on home oxygen with plans for follow-up imaging and daptomycin allergy testing. Discussion Diagnosing AEP was challenging given bronchoscopy deferral and concurrent infections. Nonetheless, treating probable AEP with steroids resulted in patient recovery, though treatment was complicated by difficulty stopping daptomycin for his graft infection. Unlike evidence favoring shorter and lower (2- vs 4-weeks, 198mg vs 265.8mg equivalent dexamethasone, respectively) steroid dosing, our patient required a 3-week, 320mg dexamethasone course. Thus, treating AEP with higher total steroids may be warranted in appropriate settings, especially when offending agents are not easily identified or removed. This abstract is funded by: None