A 17-year-old Canadian teen who narrowly escaped needing a double lung transplant to save his life is believed to have developed the first suspected case of “popcorn lung” associated with vaping.
Despite its name, there is nothing trivial about it. The case represents a potentially fatal lung injury experts had long suspected vape products were capable of causing, and it comes as the number of teens vaping and the number of vaping-related illnesses are on the rise in both Canada and the United States.
In a report fast-tracked by Canada’s top medical journal, doctors describe how the previously healthy London, Ont. high-school student spent 47 days in hospital, much of it on aggressive life support, including tethered to a machine used to rescue dying people during the SARS outbreak of 2003.
London health officials first revealed the case — now believed the first, or “index case” of vaping-related lung injury in Canada — in September, but only now have details been published.
He got very sick, very quickly
The boy had vaped daily for five months, alternating between different flavoured cartridges and regularly adding THC to his vaping fluid, when he developed a sudden fever and severe cough.
“He got very sick, very quickly,” said Dr. Karen Bosma, an intensivist at London Health Sciences Centre and lead author of the report published Thursday in the Canadian Medical Association Journal.
The unidentified youth arrived in the emergency department of his local hospital one week after his symptoms began. He was diagnosed with pneumonia and sent home with a prescription for antibiotics.
Five days later, he was back at hospital with worsening “dyspnea” — air hunger. He was struggling to get air into his lungs. X-rays and a CT scan of his chest showed a phenomenon known as the “tree-in-bud” pattern.
The main airways in the lungs branch like a tree. The further you go the more numerous the airways.
His medical team believe he developed bronchiolitis obliterans, an inflammation of the thin-walled, tiny airways called bronchioles that go to the furthest parts of the lung. Normally the tubes are filled with air, and air appears black on a CT scan. But when they become inflamed, the airways become impacted with inflammatory cells that appear white on a CT scan. “They look like, literally, a tree with branches with tiny buds on the ends of them,” Bosma said.
It’s different from the pattern of injury behind a rash of of vaping related illnesses and deaths in the U.S. known as EVALI, or “e-cigarette, or vaping, product use associated lung injury.”
In those cases, American health officials have named vitamin E acetate (found in THC oil) as a “chemical of concern.”
In the London case, the working suspicion is diacetyl, a chemical best known for the buttery flavour in microwave popcorn and used in many vaping liquids. Decades ago, the compound was linked to outbreaks of “popcorn worker’s lung” in factory workers in microwave popcorn plants. The London youth’s lungs showed the same eerie pattern.
His airways were narrowing rapidly. There were frothy secretions, liquid and bubbles, within the air tubes. He developed respiratory failure — “he couldn’t get enough oxygen into his blood, and he couldn’t get enough carbon dioxide out of his blood,” said Dr. Matthew Stanbrook, a staff respirologist at Toronto Western Hospital and deputy editor of the medical journal.
You never want to see a previously healthy kid end up on life support
As carbon dioxide builds up, people breathe faster and harder but still can’t clear the carbon dioxide. By the time he was connected to life support, the teen was breathing at a rate of 50 breaths per minute; normal breathing is 12 to 20 breaths per minute.
He was taken to intensive care and put on aggressive resuscitative measures, first a ventilator, “but even the ventilator wasn’t enough to do the work of breathing for him,” said Bosma, an associate scientist at Lawson Health Research Institute. He was connected to ECMO, or extracorporeal membrane oxygenation, where a pump circulates blood through an artificial lung back into the bloodstream.
Once on ECMO, he stabilized. “But then the question was, ‘how are we ever going to get this youth off these very aggressive and invasive forms of life support,” Bosma said.
“Is he going to need new lungs?”
She sat down with his family. “They were aware of how serious this was. They were aware that he could die. And I think it was all rather overwhelming.
“They handled everything extremely well, under the circumstances. They were willing, obviously, for their loved one to have every opportunity to be given to survive, even if that included needing a lung transplant,” she said. “But they were also aware that he was at high risk of dying.”
Twenty-one days after he was admitted to hospital, the teen was transferred on ECMO to a transplant centre.
There, doctors began treating him with higher doses of steroids. He slowly improved over the next two weeks. He was weaned from the ECMO and ventilator, his tracheostomy (a tube in his neck) was removed and he was sent home after a total of 47 days in hospital.
“As a physician and as a scientist and as a mother, you never want to see a previously healthy kid end up on life support,” Bosma said. “This could have been any kid.’
The youth has likely suffered lasting damage to his airways. “He’s lost a lot of his lung function,” said Stanbrook, who wasn’t involved in the case but who has expertise in the disease. It would be similar to someone with chronic obstructive pulmonary disease who smoked for years, and lost half his lung function.
“His lungs are overinflated, like a balloon that’s already blown up,” Stanbrook said. “Every time he breathes it’s like trying to blow up a balloon that’s already blown up, stretch an already stretched lung.” It gets hard to do things that require exertion.
“That is what this young man is facing, in all likelihood for the rest of his life.”
With the number of teens in Canada vaping nearly doubling in recent years, it’s hard to know why this teen became so critically sick. Doctors ruled out an infection, the most common cause of inflammation in the small airways, leaving them to speculate vaping probably played a role, “given that no other possible cause was identified,” the team reported.
He vaped heavily, and deeply, with a special liking for “dew mountain, “green apple” and “cotton candy” flavours bought via an online Canadian retailer.
It’s possible he had some inherent vulnerability that made him more susceptible to lung damage, or that the particular products he was using were unusually toxic, Stanbrook said. “We simply don’t know.”
Samples from the cartridges he vaped had been thrown away, so the fluid wasn’t available for analysis, but diacetyl has been found in similarly flavoured e-liquids at levels higher than recommended safety limits, Bosma and her co-authors wrote. One study found it in more than 60 per cent of e-cigarette flavours sampled. But he also vaped THC.
In an accompanying editorial by Stanbrook, the medical journal renewed its call for a ban on flavourings in e-liquids and restrictions on advertising.
“The regulatory structure right now is a bunch of suggestions that industry is free to ignore, and widely does so, that basically legitimizes what was an illegal industry before May of 2018, and basically gives it its blessing without any enforcement,” Stanbrook said.
As of Nov. 13, Canada has had eight confirmed or probable cases of severe vaping-related lung disease — three in Quebec, two in New Brunswick and three in B.C.
The U.S. has seen at least 2,172 cases and 42 deaths.