E-cigarettes: What evidence links vaping to acute lung injury and respiratory failure?

On September 18, 2019, the Middlesex-London Health-Unit (London, Canada) reported that a previously healthy, high-school student who had vaped nicotine daily, required hospitalization for life-support and had recovered. A week later, another single case was reported in Montreal, Quebec. These Canadian cases followed published cases of e-cigarette lung toxicity including a recent cluster of 53 patients in Illinois and Wisconsin and a 5 patient-cluster in North Carolina, both published on September 6, 2019. As of October 2019, there have been 26 deaths and 1,299 cases of lung injury linked to e-cigarettes. These reports have created widespread concern among clinicians and the public, creating a need to understand what we know at this point, with the caveat being that there is no clear understanding of the causes of vaping-related lung-toxicity. Most patients were previously healthy teenagers or young-adults with progressive dyspnea, hypoxemia, nausea and tachypnea with no evidence of bacterial infection while reporting recent e-cigarette use with nicotine and/or tetrahydrocannabinol. Chest computed-tomography findings included hypersensitivity-pneumonitis, diffuse alveolar hemorrhage, consolidation and ground-glass opacities. Most patients were treated with corticosteroids and symptoms resolved so that hospital discharge and community-based care could be undertaken. There have been no reports of long-term follow-up in survivors.