The potential association between use of marijuana oils or concentrates in electronic cigarettes (e-cigarettes) and lipoid pneumonia was highlighted in a recent Morbidity and Mortality Weekly Report published by the US Centers for Disease Control and Prevention (CDC).
The authors examined 5 adult cases (ages 18-35) reported from 2 hospitals in North Carolina. Patients had experienced several days of worsening dyspnea, nausea, vomiting, abdominal discomfort, and fever. On examination, patients demonstrated tachypnea with increased work of breathing and hypoxemia. Bilateral lung infiltrates were found on chest radiography. All of the patients had reported recently using marijuana oils or concentrates in e-cigarettes. The devices had refillable chambers or interchangeable cartridges with tetrahydrocannabinol vaping concentrates or oils, which were purchased on the street.
Of the 5 patients, 3 required intensive care for acute respiratory distress failure, one of whom required intubation and mechanical ventilation. Initially, all of the patients were treated for presumed community-acquired or aspiration pneumonia using either a 2-drug combination of ceftriaxone and azithromycin or a fluoroquinolone. However, within 48 hours of admission, they all developed worsening respiratory failure. In addition, blood and sputum cultures were negative for bacterial pathogens, and tests for influenza, Mycoplasma, and Legionella were also negative.
Diffuse basilar-predominant infiltrates with a range of ground glass opacities and nodular (or “tree-in-bud”) infiltrates were observed on chest computed tomography.
Three patients underwent bronchoscopy with bronchoalveolar lavage, which yielded a combination of neutrophils, lymphocytes, and vacuole-laden macrophages, but without evidence of alveolar hemorrhage or eosinophilia. Lavage cytology confirmed extensive lipid presence within alveolar macrophages. Based on clinical history, radiography, and laboratory and bronchoscopic diagnostics, all 5 patients were diagnosed with acute exogenous lipoid pneumonia.
The patients were treated with intravenous methylprednisone and improved within 24 to 72 hours of administration; all of the patients survived and were discharged home with a taper of oral prednisone.
“One potential explanation for acute lipoid pneumonia among these patients is that aerosolized oils inhaled from e-cigarettes deposited within their distal airways and alveoli, inciting a local inflammatory response that impaired vital gas exchange,” the authors wrote.
They concluded that further investigation of the specifics of these acute lung injuries is warranted, especially given the ongoing multistate outbreak.
Davidson K, Brancato A, Heetderks P, et al. Outbreak of electronic-cigarette—associated acute lipoid pneumonia — North Carolina, July–August 2019 [published online September 6, 2019]. MMWR Morb Mortal Wkly Rep. doi:10.15585/mmwr.mm6836e1