New research is homing in on what may underlie the vaping-linked lung disease that, as of December 4, 2019, has caused 2,291 hospitalizations and 48 deaths. When researchers at the Mayo Clinic reviewed lung biopsies of 17 patients with clinically suspected vaping-associated lung injury, they found that all suffered from an acute injury suggestive of a toxic injury. Acute injuries included acute fibrinous pneumonitis, diffuse alveolar damage, and organizing pneumonia.
“From a pathology standpoint, we’re seeing in the lung what looks like a toxic chemical exposure that is being inhaled into the lung and causing a chemical-like burn,” said Brandon T. Larsen, MD, PhD, associate professor of laboratory medicine and pathology at the Mayo Clinic in Scottsdale, Ariz., and senior author of the study.
Researchers at the Cleveland Clinic saw similar evidence of acute toxic injury associated with vaping in a separate cohort of patients.
What the Mayo Clinic researchers did not find is an accumulation of oil in the lungs, which the Centers for Disease Control and Prevention (CDC) reported to be a potential cause of lung injury.
What remains unknown is what the exact toxin is and how it creates the lung injury. “We know some things, but we don’t have the complete picture yet,” Dr. Larsen said. “This is a very complicated problem, and at the end of the day it is probably a multifactorial problem.”
Researchers are trying to answer questions for which an answer is lacking, he said, such as which variables contribute to the toxic reaction. This could range from the substances in the vaping juice itself (such as flavoring, drugs added, vitamin E), variation in the vaping pens on the market, variation in the heating coils or metals used, and the effect of different temperatures used to heat the vaping juice.
“There very well could be a role for vitamin E, but not in the way we were originally assuming,” he said. “I don’t think it is as simple as [accumulating vitamin E in the lungs], but vitamin E could be toxic itself or could be a source of a toxic byproduct when it is heated and inhaled into the lung.”
Although vaping is a tough problem, Dr. Larsen said there are simple things that otolaryngologists can do to counsel patients. These include asking patients about their vaping habits just as they do about smoking habits, informing patients about the potential risks of vaping, and following the CDC recommendations on counseling patients.
—Mary Beth Nierengarten