Vaping lung disease is a newly identified lung disease with high morbidity and mortality, only recently recognized in the United States with fifty-seven deaths now reported and over 2600 cases of lung injury now attributable to e-cigarette use in the USA (as of January 7,2020). Many of the cases involve the mixing of cannabis (THC) components with the e-cigarette vaping liquids.
The recognition of this entity is highly important, as the incidence of e-cigarette use has exponentially escalated in school-age children in the USA.
The mechanics of a basic vaping device are shown in Figure 1. Devices now available can be quite compact in size. Juul pods (Figure 1) have been a very popular device but have lost favor recently in part due to poor publicity related to EVALI. A single Juul pod delivers the nicotine equivalent of 30 cigarettes.
One of the more popular devices now amongst adolescents and young adults is the Puff Bar device (Figure 3). It comes in a wide array of flavors that are highly appealing to young adults and children. Banana Ice is a particularly popular flavor and tastes like banana NERD candy. Empty refill cartridges can also be readily purchased online and can be filled with anything, including THC products.
Laboratory analysis to date has shown that Vitamin E acetate, used as an additive primarily with THC-vaping products, is a likely causative agent of the newly arising EVALI disease. Vitamin E acetate was the only ubiquitous substance identified in the bronchoalveolar lavage specimens from the samples taken from individuals with EVALI. Although, additionally, coconut oil and limonene were each identified in one EVALI patient.
The histopathology of EVALI is characterized by severe bronchiolitis (with mucosal edema, sloughing of epithelium and peribronchiolar organization; Figure 4). Foamy lipid-laden macrophages may also be seen. Severe injury can progress to diffuse alveolar damage or formation of hyaline membrane.
The clinical course from onset of symptoms is short (within days of insult) and begins with an exudative edematous phase, progressing to an acute inflammatory phase within 1-5 days and evolving into an organizing fibrinous phase within one to two weeks.
In early investigations, four radiographic patterns have been described (Figure 5). These include organizing pneumonia, diffuse alveolar damage, diffuse alveolar hemorrhage and centrilobular nodularity. Interestingly, many of the cases have additionally shown the finding of sub-pleural sparing of disease.
The number of new cases presenting seems to have plateaued as of late 2019, due to the identification of Vitamin E acetate as a causative factor. However, new cases are still arising. Legislative actions are being initiated to provide better regulation of the availability of the vaping products and to diminish their availability to children in the USA. However, vaping remains as an epidemic in school age children (especially adolescents and teenagers) and is extremely popular on college campuses across the USA.