The death of an Illinois patient with a vaping-related lung disease brings a new urgency to identifying those at risk of developing the dangerous illness before severe symptoms appear.

Some of the vaping-related lung illnesses have been in teenagers — some as young as 15, according to Dr. Jacob Kaslow, a pediatric pulmonary fellow at Monroe Carell Jr. Children’s Hospital at Vanderbilt in Nashville, Tennessee.

That means parents and pediatricians could be one of the first lines of defense when it comes to spotting symptoms and identifying at-risk adolescents.

"Everybody needs to be on alert," Dr. Wendy Sue Swanson, a pediatrician at Seattle Children's Hospital, said.

Indeed, the popularity of e-cigarettes among teenagers has surged in recent years. The CDC has reported a 78 percent increase in high school students who said they'd vaped between 2017 and 2018.

Swanson said pediatricians already screen older kids and teenagers for tobacco use, but the recent surge in vaping-related illnesses suggests this should be front-of-mind for physicians.

"When a child comes in with any respiratory complaints — particularly in the middle school or high school ages — we need to screen them for use of vaping products, and possibly triage them differently until we know what's going on," Swanson said.

Indeed, doctors are increasingly changing their first line of questioning to include vaping history when they encounter patients in respiratory distress.

Teenagers with a history of vaping have complained of coughing and lungs that feel like they're burning when they try to inhale deeply. Symptoms may be particularly apparent in teen athletes, who struggle to fill their lungs with enough air to keep up with demanding physical workouts.

"If a child develops a cough, and it's unusual and comes out of nowhere," Swanson said, "parents really should be asking, 'Hey honey, have you been vaping?'"

"Have open conversations about this without judgment with your teens, and let them know that there are both long-term effects, and also that there have been children who have been put in the hospital on breathing support because they were using these devices," she said.

At least 193 cases of the mysterious illness are under investigation across the country, the Centers for Disease Control and Prevention reported Friday. That number is almost surely an underestimation, as cases may go undetected as physicians spend time ruling out other causes when patients arrive at the hospital with what appears to be viral or bacterial pneumonia.

"The difficulty with many of these cases is that the patients are not presenting with the same constellation of symptoms," said Kaslow, whose hospital has treated at least four cases of vaping-related respiratory illness over the past six months.

Many, if not all, of those patients complained of headache, shortness of breath and cough.

But others had much more severe symptoms: coughing up blood, atypical infections, or unexpected difficulties following surgery.

The only common link between all of the cases is a history of vaping products that contain either nicotine or THC, the psychoactive ingredient in marijuana.

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