E-Cigarette– or Vaping Product–Associated Lung Injury (EVALI)

Key Features

Essentials of Diagnosis

• Presentation is nonspecific

• Illness is usually subacute

• Respiratory, gastrointestinal, and constitutional symptoms are common

• Tachycardia and tachypnea may also be present

General Considerations

• No single causative agent has been identified

• Most cases involve vaping products containing tetrahydrocannabinol (THC) or nicotine or both

• Postulated factors contributing to the development of EVALI include

  • E-cigarette flavorings

  • Exposure to diacetyl (a popcorn flavoring that has been associated with lung injury)

  • THC

  • Adulteration of THC

  • Adulteration of delivery devices

  • Vitamin E acetate (used as a thickening agent)

• Given the nonspecific nature of the presentation, especially during the influenza season and the COVID-19 pandemic, providers must have a high degree of clinical suspicion and ask patients specifically about vaping

Demographics

• An outbreak of EVALI began in the United States in 2019

• Approximately 66% of patients have been male and 80% are under age 35

Clinical Findings

Symptoms and Signs

• Respiratory symptoms (95%), including

  • Cough

  • Shortness of breath

  • Chest pain

• Gastrointestinal symptoms (77%), including

  • Nausea

  • Vomiting

  • Diarrhea

• Constitutional symptoms (85%), including

  • Fever

  • Chills

  • Weight loss

• Tachycardia (55%) and tachypnea (45%)

• Of note, 57% of cases have a recorded room air oxygen saturation of < 95%

Differential Diagnosis

• Community-acquired pneumonia

• COVID-19 (can be detected by reverse-transcription (RT)-PCR testing of respiratory tract secretions, ie, expectorated sputum, nasopharyngeal swab or bronchoalveolar lavage specimens)

• Acute eosinophilic pneumonia

• Acute respiratory distress syndrome

• Hypersensitivity pneumonitis

• Lipoid pneumonia

• Organizing pneumonia

• Influenza (can be detected by RT-PCR testing of respiratory tract secretions, including nasopharyngeal washings, in season)

Diagnosis

Laboratory Findings

• No laboratory findings are specific for diagnosis of EVALI

• Leukocytosis

• Elevated C-reactive protein

• Elevated erythrocyte sedimentation rate

Imaging

• Chest radiograph typically shows bilateral pulmonary opacities

• Chest CT scans are nonspecific and may show patterns seen in other disorders, such as

  • Hypersensitivity pneumonitis

  • Acute respiratory distress syndrome

  • Diffuse alveolar hemorrhage

  • Acute eosinophilic pneumonia

  • Lipoid pneumonia

  • Giant cell interstitial pneumonia

  • Cryptogenic organizing pneumonitis

Treatment

• Published case reports of hospitalized patients with EVALI have described rapid improvement following administration of corticosteroids

Outcome

Prognosis

• The natural progression of EVALI is not known

• Over 95% of reported cases required hospitalization: 47% were admitted to intensive care, 22% were intubated and many died

References