A 34-year-old male transferred from an outside hospital presented to the emergency department with dyspnea, mild fever, and myalgia. Pulse oximetry showed an O2 saturation of 85% at room air, which increased to 95% with the application of 4 L/min O2 by nasal cannula. On the initial chest radiograph, diffuse ill-defined haziness with multifocal Kerley B lines was observed in both lungs, especially in both lower lobes. Bilateral pleural effusion was also seen (Fig. 1A).
On the chest CT, multiple patchy consolidations with a lower lobe predominance and peripheral distribution were demonstrated in both lungs. In addition, ill-defined ground-glass opacities and diffuse interlobular septal thickening were seen in both lungs, especially in the basal segments. Small amount of pericardial effusion and bilateral pleural effusion was present as well (Fig. 1B). Initial lab results revealed elevated erythrocyte sedimentation rate (26 mm/hr), C-reactive protein (20.570 mg/dL) levels, and leukocytosis (21.59 x 103/uL), while the eosinophil ratio (1.7%) was within normal limits. Our first impression from the imaging and lab findings were viral pneumonia, coronavirus disease 2019 (COVID-19) pneumonia, or interstitial pneumonia such as scrub typhus. Cryptogenic organizing pneumonia and AEP were also possible differential diagnoses.
Follow-up peripheral blood eosinophil levels, apprehended four days later, were elevated (9.7%). Additional bronchoscopy showed no endobronchial lesion, however, bronchoalveolar lavage (BAL) fluids revealed increased eosinophil ratio (79%) levels, suggesting the possibility of eosinophil related lung disease. Additional culture and infectious lab results were negative for infectious causes, such as COVID-19, tuberculosis, scrub typhus, and other infectious pathogens.
With a careful and more thorough history, the patient revealed to be a 14 pack-year smoker and used vaping e-cigarettes. Other than vaping 5 cc of nicotine a day, he denied usage of different substances such as THC. With the initiation of steroid treatment and cessation of vaping, the patient's diffuse ill-defined bilateral haziness decreased on follow-up chest radiographs (Fig. 1C). After three months of steroid treatment and then tapering, the patient did not show signs nor symptoms of relapse. By the proposed diagnostic criteria, we were able to make a final diagnosis of only-nicotine vaping EVALI manifested as AEP.
This study was approved by the Institutional Review Board of our institution and the requirement for informed consent was waived (IRB No. 2021AS0375).