LIPID LADEN MACROPHAGES IN E-CIGARETTE OR VAPING PRODUCT USE-ASSOCIATED LUNG INJURY

Abstract

SESSION TITLE: Medical Student/Resident Tobacco Cessation and Prevention Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Electronic-cigarette or vaping, product use-associated lung injury (EVALI) was first reported to the CDC in August 2019 and has to lead to a significant number of hospitalizations and deaths [1]. Various patterns of acute lung injury including diffuse alveolar damage, acute fibrinous pneumonitis, and organizing pneumonia have been described in association with EVALI [2]. However, the presence of lipid-laden macrophages in BAL has been consistently noted in some series of EVALI [3]. Here, we present a unique case of EVALI in which a very high number of lipid-laden macrophages were noted. CASE PRESENTATION: A 44-year-old man who had been vaping nicotine and THC regularly presented with progressively worsening dyspnea. He was febrile, tachycardic, tachypneic and hypoxemic upon presentation. Computed tomography of the chest revealed multi-focal bilateral hazy ground-glass opacities with subpleural sparing and inter-lobular septal thickening. He underwent flexible bronchoscopy for further evaluation. Bronchoalveolar lavage (BAL) showed a high number of lipid-laden macrophages on the oil-red-O stain with a Colombo count over 200. He was started on systemic corticosteroids for presumed EVALI resulting in significant improvement of his condition. He was discharged home in stable condition on day 6 of admission. DISCUSSION: A total of 2,807 hospitalized EVALI cases with 68 reported deaths have been confirmed by the Centers for Disease Control and Prevention in the United States with a majority of cases being associated with tetrahydrocannabinol containing products. Radiographic abnormalities of interlobular septal thickening along with bilateral hazy ground-glass opacities have been described with this condition and histopathological features include acute fibrinous pneumonitis, diffuse alveolar damage, lipoid pneumonia and organizing pneumonia. Lipid-laden macrophages in BAL fluid have been noted in many patients with EVALI but the significance of lipid-laden macrophages in diagnosing this condition remains unclear. However, the presence of lipid-laden macrophages in a patient with a history of electronic-cigarette or vaping product use and no evidence of infection should strongly suggest a diagnosis of EVALI. To our knowledge, no previous case with such a high number of lipid-laden macrophages has been reported. CONCLUSIONS: A rapid identification tool for EVALI is required given the current outbreak. The presence of lipid-laden macrophages in the BAL fluid may serve as such a marker in the appropriate clinical setting. Prompt treatment with systemic corticosteroids should be considered once lipid-laden macrophages are identified in patients with a history of vaping. Reference #1: Perrine CG, Pickens CM, Boehmer TK, et al. Characteristics of a Multistate Outbreak of Lung Injury Associated with E-cigarette Use, or Vaping - United States, 2019 [published correction appears in MMWR Morb Mortal Wkly Rep. 2019 Oct 11;68(40):900]. MMWR Morb Mortal Wkly Rep. 2019;68(39):860-864. Published 2019 Oct 4. doi:10.15585/mmwr.mm6839e1 Reference #2: Butt YM, Smith ML, Tazelaar HD, et al. Pathology of Vaping-Associated Lung Injury. N Engl J Med. 2019;381(18):1780-1781. doi:10.1056/NEJMc1913069 Reference #3: Maddock SD, Cirulis MM, Callahan SJ, et al. Pulmonary Lipid-Laden Macrophages and Vaping. N Engl J Med. 2019;381(15):1488-1489. doi:10.1056/NEJMc1912038 DISCLOSURES: No relevant relationships by Moeezullah Beg, source=Web Response No relevant relationships by Mahnoor Mir, source=Web Response No relevant relationships by Jay Peters, source=Web Response