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A3572 - Severe Fixed Obstructive Lung Disease in a Former Smoker with Heavy E-Cigarette Use
Author Block: T. V. Macedonia1, S. D. Krefft2, C. S. Rose2; 1University of Colorado Anschutz Medical Campus Colorado School of Medicine, Aurora, CO, United States, 2University of Colorado Anschutz Medical Campus Colorado School of Medicine, Aurora, CO, United States; National Jewish Health, Denver, CO, United States.
Introduction: Use of electronic nicotine delivery systems (ENDS) continues to grow, with little known about chronic health effects of these complex chemicals. Diacetyl-containing flavorings (found in some ENDS solutions) have been linked to occupational fixed airflow limitation. We describe a former smoker with heavy vaping, acute onset dyspnea, and severe fixed obstruction.
Case Description: A 45-year-old man with an unremarkable past medical history developed sudden severe exertional dyspnea. He was a former smoker (40 pack-years, having stopped 18 months earlier) who had completely transitioned to vaping 9 months before symptom onset. He vaped 4 puffs every 15-30 minutes, at the second highest smoke level but with progressively decreasing nicotine levels.
He saw his primary care physician who noted a normal chest x-ray. His exertional dyspnea worsened despite treatment with antibiotics, albuterol, budesonide/formoterol, tiotropium and prednisone. He stopped vaping completely six weeks after symptom onset, but dyspnea persisted.
Spirometry showed severe obstruction with an FEV1 of 1.0 L (24% predicted, PP), FVC 2.3 L (45 PP), and FEV1/FVC ratio 41%. High resolution chest computed tomography (HRCT) scan showed mosaicism with severe air trapping and patchy ground glass opacities. Serum ANA, rheumatoid factor, ANCA, ESR, IgE and alpha-1-antitrypsin were normal. Supplemental oxygen for exertional hypoxemia was begun. Lung biopsy showed lymphoplasmacytic respiratory bronchiolitis with peribronchial aggregates of pigmented macrophages without organizing pneumonia or obliterative bronchiolitis.
Despite vaping cessation and treatment with mycophenolate mofetil, azithromycin and prednisone, spirometry continued to show severe fixed obstruction. Nine months later, total lung capacity measured 8.52 L (123 PP), residual volume 5.78 L (272 PP), FEV1 0.79 L (19 PP), FVC 2.0 L (38 PP), FEV1/FVC ratio 40% and DLCO 20.50 (54 PP). HRCT was unchanged.
Gas chromatography/mass spectrometry and infrared spectroscopy analysis of the heated vaping liquid showed a complex mixture including pyridines, furfural, vanillin, nicotyrine, aldehydes, glycerins, and propylene glycol, without detectable alpha-diketones/diacetyl.
Discussion: There are a few case reports of acute respiratory illnesses linked to vaping that resolved with exposure cessation. To our knowledge, this is the first reported case of acute dyspnea followed by severe persistent fixed airways obstruction temporally associated with heavy vaping in a former smoker. Severe airflow limitation remained stable after vaping cessation, with no apparent response to systemic therapy. Lung function and imaging abnormalities were discordant with findings on surgical lung biopsy. As the market for e-cigarettes grows, further attention to possible associated pulmonary toxicity is vital.