Chronic Eosinophilic Pneumonia - A Challenging Case with Multiple Triggers

Abstract

Introduction Eosinophilic pneumonia is a class of lung diseases characterized by accumulation of eosinophils in the lung. Chronic eosinophilic pneumonia (CEP) is diagnosed through radiographic imaging and bronchoalveolar lavage (BAL) with elevated eosinophil count (>25%) in the setting of pulmonary symptoms for more than 2 weeks. While CEP is often an idiopathic disease, it may also be caused by medications, illicit substances, or infections. Identifying the trigger is imperative for successful treatment. A 71-year-old man presented with fever and chronic shortness of breath that started after COVID-19 infection (6 months prior to presentation). Medical history was also significant for multiple myeloma, asthma, hypertension, type 2 diabetes, coronary artery disease, chronic kidney disease, and Alzheimer's dementia. Current medications included bortezomib, pomalidomide, aspirin, clopidogrel , donepezil, tramadol and insulin. Lenalidomide was discontinued 3 months prior due to generalized skin rash and high peripheral eosinophilia (19%). On presentation, physical exam revealed mild respiratory distress, bibasilar crackles, and bilateral pedal edema. Long COVID Syndrome was suspected. He was started on antibiotics and diuretics with no improvement. Labs revealed mild peripheral eosinophilia. Chest X-ray showed diffuse bilateral reticular nodular opacities predominantly on the right. CT chest revealed reticulonodular infiltrates in both lungs predominantly in the right upper lobe with small pleural effusion. Bronchoscopy with BAL was negative for infection but revealed 28% eosinophils. Pomalidomide was discontinued and oral prednisone started. Discussion: CEP is part of a group of eosinophilic lung diseases characterized by abnormal accumulation of eosinophils in the lung tissue. Symptoms include dyspnea and cough in the majority of cases, but may also include fever, sinusitis, rhinitis, fatigue and weight loss. The radiographic hallmarks are bilateral alveolar infiltrates peripherally predominantly in the upper lobes and may be ground glass or consolidation. The presence of an elevated eosinophil count (>25%) in a BAL confirms the diagnosis. Though often idiopathic, identification of possible causes is important for proper management. In our case, the patient has multiple risk factors including possible Long COVID Syndrome and malignancy. Medications such as bortezomib, lenalinomide and pomalidomide have been known to cause diffuse lung injury. To the best of our knowledge there is one case report illustrating Lenalinomide related CEP. History of asthma is present in most cases of idiopathic CEP. Our patient had multiple potential triggers for CEP. We suspect that CEP was medication-related in this case. (Figure Presented).