AN UNUSUAL CAUSE OF ACUTE EOSINOPHILIC PNEUMONIA

Abstract

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: We report an unusual case of interstitial lung disease in a patient suffering from alcoholism. CASE PRESENTATION: A 44 year old woman with a history of alcoholism presented with a 5 day history of shortness of breath, fevers and malaise. She was found to be hypoxemic and computed tomography of the chest showed bilateral patchy ground glass opacities with interlobular septal thickening and subpleural sparing. She had no exposures and her only medication was monthly subcutaneous naltrexone to maintain sobriety. She had received 4 doses, the most recent being the day of her onset of symptoms. Laboratory testing was significant for leukocytosis and elevated peripheral eosinophilia. Additional testing was negative for autoimmune or vasculitis markers, and parasitic or filarial presence. Bronchoalveolar lavage (BAL) was performed and revealed eosinophilic predominance of 49%. Pathology from transbronchial biopsies demonstrated eosinophilic pneumonia with intra-alveolar fibrin deposition. Steroids were initiated and her imaging abnormalities and oxygen requirement resolved within 48 hours. All of the above findings were felt to be most consistent with acute eosinophilic pneumonia secondary to naltrexone. The patient was cautioned to not be re-exposed to the same medication again. DISCUSSION: Acute eosinophilic pneumonia (AEP) is a febrile illness with hypoxemic respiratory failure and eosinophilic infiltration of the pulmonary parenchyma (1). Characteristic BAL shows marked eosinophilia in the absence of infection, atopy or asthma. AEP is mostly idiopathic but other causes include hypersensitivity to drugs, inhaled agents, or environmental exposures (2). Naltrexone acts by blocking the mu-opioid receptor and modifying the hypothalamic-pituitary-adrenal axis to suppress alcohol consumption. The subcutaneous form of this medication is thought to aid in adherence as it is administered once monthly and achieves a steady therapeutic level. In a randomized control trial showing the efficacy of long-acting injectable naltrexone, there was one serious adverse event of AEP judged to possibly be related to the study medication (3). In AEP, patients typically present with an acute onset of fever, nonproductive cough and dyspnea of less than 4 weeks duration. Diffuse bilateral pulmonary infiltrates are seen on imaging. Pathologic features include acute and organizing diffuse alveolar damage, as well as interstitial and alveolar eosinophils. The mainstay of treatment is systemic glucocorticoids. Most patients improve rapidly in response to glucocorticoids within 24-48 hours (2). CONCLUSIONS: In our case, the patient’s clinical history, radiographic, laboratory and BAL findings were consistent with AEP. Other causes were ruled out and thus AEP was determined to be secondary to long-acting injectable naltrexone. Providers should recognize that AEP is an extremely rare, but reported adverse effect of this drug. Reference #1: Allen JN, Pacht ER, Gadek JE, et al. Acute eosinophilic pneumonia as a reversible cause of noninfectious respiratory failure. N Engl J Med.1989;321:569–574. Reference #2: Rhee CK, Min KH, Yim NY, Lee JE, Lee NR, Chung MP, Jeon K. Clinical characteristics and corticosteroid treatment of acute eosinophilic pneumonia. Eur Respir J. 2013;41(2):402 Reference #3: Garbutt JC, Kranzler HR, O’Malley SS, et al. Efficacy and Tolerability of Long-Acting Injectable Naltrexone for Alcohol Dependence: A Randomized Controlled Trial. JAMA. 2005;293(13):1617–1625. DISCLOSURES: No relevant relationships by Jeannine Foster, source=Web Response No relevant relationships by Thoris Pan, source=Web Response No relevant relationships by Haala Rokadia, source=Web Response