Correct!
3. E-cigarette / vaping-associated lung injury
While it is difficult to completely exclude a pulmonary manifestation of an as-yet undeclared connective tissue disorder, the patient’s symptoms are not particularly suggestive of such- he has not complained of joint pain or stiffness or other similar rheumatological complaints, not is there clinical or laboratory evidence of such. The lack of eosinophilia on bronchoalveolar lavage and at lung biopsy excludes the diagnosis of acute eosinophilic pneumonia. Acute interstitial pneumonia is technically possible, but no evidence of hyaline membrane formation was seen at lung biopsy. The diagnosis of lipoid pneumonia can be made when foci of macroscopic fat are seen within areas of ground-glass opacity or consolidation at chest CT (not the case for this patient), or when pulmonary tissue sampling shows variably-sized fat droplets associated with a foreign body giant cell reaction; lipid-laden macrophages, however are, by themselves, very non-specific, and can be seen in lung biopsies of patients with patients with infections, drug reactions, and autoimmune disorders. Therefore, the diagnosis of lipoid pneumonia should not be suggested solely on the basis of the presence of lipid-laden macrophages at lung biopsy. However, at lung biopsy, the presence of foamy macrophages and similar foamy change in type II pneumocytes in the presence of acute lung injury has been considered suggestive of e-cigarette / vaping-associated lung injury.
With the biopsy information in hand, the patient was questioned regarding e-cigarette use / vaping. He admitted to vaping tetrahydrocannabinol containing “pods” over the previous 6 months in an effort to quit combustible tobacco smoking. In the month prior to presentation he had accelerated his vaping to stave off cigarette cravings. The patient’s antibiotic therapy was withdrawn and corticosteroids were begun. After 2-3 days, the patient’s symptoms improved and chest radiography (Figure 5) was repeated.
Figure 5. Frontal (A) and lateral (B) chest radiography performed just over a week following initial presentation.
Regarding the follow up chest radiograph (Figure 5), which of the following statements is most accurate? (Click on the correct answer to be directed to the fourteenth and final page)