E1321. Electronic Cigarette or Vaping Product Use-Associated Lung Injury (EVALI) vs Differential Diagnoses: Side by Side Comparisons of CT Findings
  1. Karen Man; Morristown Medical Center
  2. Sean Mendonca; Morristown Medical Center
  3. Isaac Daudelin; Morristown Medical Center; Rutgers New Jersey Medical School
  4. Stella Lam; Morristown Medical Center
Electronic cigarette or vaping product use-associated lung injury (EVALI) has increased in prevalence with the increasing popularity and use of electronic cigarettes (e-cigarettes) and vaping products. Some users believe that these products are associated with less overall health risk compared to conventional tobacco products. E-cigarettes and vaping materials have also appealed to younger demographics through targeted marketing (e.g. discreet e-cigarettes shaped like USB flash drives) and candy-like flavorings which may be more palatable to younger populations. Between 2011-2018, the prevalence of e-cigarette use increased from 1.5% to 20.8% among U.S. high school students. However, the aerosols from these e-cigarettes and vaping products have the potential to induce a chemical pneumonitis with resultant hypoxemia -- in some cases requiring mechanical ventilation support -- which can indiscriminately affect vaping product users, including those who would be otherwise young and healthy. Distinct computed tomography (CT) imaging patterns can be seen in the setting of EVALI, and the radiologist may be the first to suggest the disorder, which can prompt further elicitation of relevant history and appropriate diagnosis. Yet, it is important to keep in mind that CT findings which may be seen in the setting of EVALI are not specific and may overlap with other infectious or inflammatory disorders of the lung. Thus, it is important for the radiologist to be able to recognize the imaging patterns in EVALI, as well as to keep in mind differentials with similar imaging features.

Educational Goals / Teaching Points
After completion of this educational exhibit, the learner will be familiar with: CT lung findings in the setting of EVALI, possible differential diagnoses that may occur in a comparable patient population, and similar versus distinguishing CT features between EVALI and the differential diagnoses discussed.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
This exhibit will review patterns of CT findings in the setting of EVALI, including hypersensitivity pneumonitis, diffuse alveolar damage, lipoid pneumonia, and organizing pneumonia. These imaging patterns will be compared side-by-side to CT findings of other microbiology/pathology-proven diagnoses. The examples of possible differential diagnoses discussed in this presentation include: community-acquired pneumonia (Streptococcus pneumoniae infection), atypical “walking” pneumonia (Mycoplasma pneumoniae infection), viral pneumonia (influenza infection), pneumonia due to 2019 novel coronavirus infection (COVID 19), nonspecific interstitial pneumonia (NSIP), and pneumonitis related to systemic lupus erythematosus.

With the increasing popularity and use of e-cigarettes and vaping products, there has been an increasing prevalence of EVALI, which can occur in otherwise young and healthy patient populations for whom the presenting clinical symptoms may be an enigma. It is important for the radiologist to be familiar with the imaging patterns of EVALI on CT, as well as to keep in mind other infectious or inflammatory disorders of the lung that can elicit similar CT findings.