But Dr. Larsen said the Mayo researchers saw no signs of oil accumulating in the lung tissue. Instead, they saw many immune cells called macrophages with what he described as “the fine, foamy-looking appearance that is characteristic of chemical injuries.”
“So maybe we need to look more closely at the chemical compounds, and not just oils, but the chemical constituents, to figure out which ones are injurious,” Dr. Larsen said.
He said patients with lung illness from vaping had tissue damage and cell death in the lining of their airways, and in the lungs themselves. As the body reacts and tries to heal, the tissue swells and can narrow the airways. Dead cells slough off into the airways, blocking them further, and fluids leak into the lungs’ air sacs.
The swelling, tissue damage and fluid buildup can make it impossible to breathe.
“The lung is not very functional when it’s been damaged and is trying to repair itself,” Dr. Larsen said, adding that the lungs and airways have essentially been “torched.”
“There’s no reserve left while the body tries to heal itself, so people will be really sick, on a ventilator because they can’t get enough oxygen in, or carbon dioxide out,” he said. “Some patients will not recover, and will end up dying.”
He said it was too soon tell whether the survivors’ lungs would fully recover.
“Based on the severity of injury we see, at least in some of these cases, I wouldn’t be surprised if we wind up with people down the road having chronic respiratory problems from this,” Dr. Larsen said. “Some seem to recover. I don’t think we know what the long-term consequences will be.”
Two of the cases included in the Mayo Clinic report occurred before 2019, and Dr. Larsen said he suspected that the condition had existed for some time, years perhaps, but that the cases were scattered and the cause was not recognized.