SESSION TITLE: Tuesday Medical Student/Resident Case Report Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/22/2019 01:00 PM - 02:00 PM INTRODUCTION: Eosinophilia is a common laboratory finding in patients diagnosed with asthma, however combined with dyspnea and a chronic cough, other diagnoses can be overlooked.. Chronic eosinophilic pneumonia is characterized by a chronic and progressive course similar to worsening asthma with the addition of specific pathologic findings. Here we present a case of a patient with known asthma who presented with progressively worsening cough, shortness of breath and eosinophilia. CASE PRESENTATION: A 46-year-old male with a history of asthma presented to the emergency department (ED) with worsening shortness of breath at both rest and exertion for two months. The patient had associated wheezing, thick yellow sputum and rhinorrhea. At presentation he also noted a two-week history of night sweats with a ten pound weight loss. Prior to presentation the patient underwent a chest x-ray and was treated for two weeks with antibiotics. for presumed pneumonia. The patient then underwent a repeat chest x-ray and was subsequently referred for chest CT. In the ED the patient was noted to have leukocytosis of 34 K/uL with 23.2 K/uL eosinophils (68.2%) Chest X-Ray demonstrated patchy air-space opacities with a predominantly mid to upper lung zone distribution. The patient was started on methylprednisolone, ceftriaxone, and azithromycin for community acquired pneumonia and was seen by the pulmonary and infectious disease consultants. The patient was tested for angiotensin converting enzyme, P-ANCA, Aspergillus, HIV, and tuberculosis, all of which were negative. The patient clinically improved and antibiotic therapy was discontinued. Three days after admission a repeat CXR, showed improved bilateral pulmonary parenchymal abnormalities. The patient’s eosinophilia resolved within three days and the patient continued to clinically improve with a tapering course of steroid therapy. DISCUSSION: Chronic eosinophilic pneumonia (CEP)is characterized by chronic and progressive clinical features and specific pathological findings. The onset of CEP is generally insidious, either subacute or chronic. Accordingly, the symptoms often appear several months before the diagnosis is made. The diagnosis of CEP is based on the association of respiratory symptoms, alveolar or blood eosinophilia, a non-segmental pulmonary infiltration with peripheral predominance involving mainly the upper lobes on chest imaging and the exclusion of other eosinophilic lung diseases. Corticosteroid treatment results in rapid resolution of symptoms, radiologic opacities and peripheral eosinophilia as occurred in our case. CONCLUSIONS: This case demonstrates the need for physicians to broaden their differential diagnoses when considering the etiology of eosinophilia in patients with a history of asthma. Reference #1: https://www.uptodate.com/contents/chronic-eosinophilic-pneumonia?search=chronic%20eosinophilic%20pneumonia&source=search_result&selectedTitle=1∼37&usage_type=default&display_rank=1 DISCLOSURES: No relevant relationships by Jang Chadha, source=Web Response No relevant relationships by Yelenis Fuertes Yanes, source=Web Response No relevant relationships by Nida Hameedi, source=Web Response