Case 38-2019: A 20-Year-Old Man with Dyspnea and Abnormalities on Chest Imaging

E-cigarette vaping associated acute lung injury (EVALI): state of science and future research needs

"E-Cigarette (e-cig) Vaping-Associated Acute Lung Injury" (EVALI) has been linked to vitamin-E-acetate (VEA) and Δ-9-tetrahydrocannabinol (THC), due to their presence in patients' e-cigs and biological samples. Lacking standardized methodologies for patients' data collection and comprehensive physicochemical/toxicological studies using real-world-vapor exposures, very little data are available, thus the underlying pathophysiological mechanism of EVALI is still unknown. This review aims to provide a comprehensive and critical appraisal of existing literature on clinical/epidemiological features and physicochemical-toxicological characterization of vaping emissions associated with EVALI. The literature review of 161 medical case reports revealed that the predominant demographic pattern was healthy white male, adolescent, or young adult, vaping illicit/informal THC-containing e-cigs. The main histopathologic pattern consisted of diffuse alveolar damage with bilateral ground-glass-opacities at chest radiograph/CT, and increased number of macrophages or neutrophils and foamy-macrophages in the bronchoalveolar lavage. The chemical analysis of THC/VEA e-cig vapors showed a chemical difference between THC/VEA and the single THC or VEA. The chemical characterization of vapors from counterfeit THC-based e-cigs or in-house-prepared e-liquids using either cannabidiol (CBD), VEA, or medium-chain triglycerides (MCT), identified many toxicants, such as carbonyls, volatile organic compounds, terpenes, silicon compounds, hydrocarbons, heavy metals, pesticides and various industrial/manufacturing/automotive-related chemicals. There is very scarce published toxicological data on emissions from THC/VEA e-liquids. However, CBD, MCT, and VEA emissions exert varying degrees of cytotoxicity, inflammation, and lung damage, depending on puffing topography and cell line. Major knowledge gaps were identified, including the need for more systematic-standardized epidemiological surveys, comprehensive physicochemical characterization of real-world e-cig emissions, and mechanistic studies linking emission properties to specific toxicological outcomes.

Reporting of pneumothorax in association with vaping devices and electronic cigarettes

Vaping may lead to spontaneous pneumothorax, but there are few published reports on this phenomenon. We present a case of vaping-related pneumothorax and make recommendations for structured reporting of this emerging cause for pneumothorax. A normal-weight 34-year-old male presented to our emergency department with dyspnoea and back pain increasing over 24 hours. Chest X-ray showed a large right-sided pneumothorax. Three years ago, he had quit smoking cigarettes and switched to vaping. CT scan revealed bullae, and the patient received apical lung resection. Histology revealed mild alveolitis. Vaping is an emerging cause of lung injury. This report demonstrates a potential association between vaping and pneumothorax. However, structured reporting and future research are needed to establish a definitive (or causal) relationship between vaping and pneumothorax.

Radiological findings of e-cigarette or vaping product use associated lung injury: A systematic review

INTRODUCTION

Chest radiology provides an opportunity to better understand the diagnostic characteristics of e-cigarette or vaping product use associated lung injury (EVALI). This systematic review aimed to summarize the radiological findings associated with EVALI reported in the literature.

METHODS

This systematic review was conducted in accordance with PRISMA guidelines. Electronic searches of MEDLINE®, CINAHL, Embase® and CENTRAL were conducted in February 2020. Included were all English-language studies reporting radiological findings of EVALI. Data was synthesized using descriptive statistics.

RESULTS

Thirty studies comprising 184 participants were included. Mean patient age was 24.5 years old. The majority (n = 141, 76.6%) of included patients were male. The most common radiological features reported on chest x-ray were bilateral infiltrates (n = 64, 41.3%) and ground glass opacities (n = 17, 11.0%), and on chest CT were bilateral infiltrates (n = 62, 36.9%), bilateral ground glass opacities (n = 56, 33.3%), subpleural sparing (n = 29, 17.3%), pleural effusions (n = 14, 8.3%), and centrilobular nodularity (n = 13, 7.7%). Of patients with follow-up data reported (n = 81), only 28.4% (n = 23) had complete resolution of symptoms or radiological findings.

CONCLUSION

Chest radiology is the cornerstone of diagnosis and monitoring of EVALI. A wide variety of radiological findings highlight the need for standardisation of terminology in the radiological descriptions of EVALI. Common findings included bilateral infiltrates and ground glass opacities. Higher quality evidence is warranted to help develop evidenced-based guidelines for the diagnosis and management of EVALI.