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Some people feel like they spend their whole lives nursing a cold or the flu. It's a condition shared by about 1.5 million people in the United States. And many of them don't know they even have this problem. The side effects can be fatal. NPR's Angus Chen reports on a woman who spent nearly a decade trying to find out what was wrong.
ANGUS CHEN, BYLINE: Allison Feit started getting really sick as a teenager.
ALLISON FEIT: When I was 16, that's kind of when all of my sinus problems started, followed by my chest problems.
CHEN: I talked to her over Skype. She says that for nearly a decade she struggled with sinus infections. She was constantly taking decongestants and antibiotics. And she went from doctor to doctor trying to understand why she was always getting sick.
FEIT: And, you know, it was kind of like one of those things where - what else am I going to do?
CHEN: It wasn't until she was 25 that she finally started figuring her disease out. She was teaching English in Thailand.
FEIT: I was teaching a class one day. And I had this moment where I just completely forgot where I was. I felt dizzy. I felt scared. I felt panicky.
CHEN: She went to the hospital. And the doctor peeked up her nose and found - along with a terrible sinus infection - these benign growths called nasal polyps.
FEIT: He was like, you need sinus surgery. And I was like, that's great.
CHEN: This wasn't the first time. Feit had surgery for that same problem when she was 20. But when she came back to Thailand after the operation, the polyps grew back.
FEIT: And I was kind of like, I just flew all the way back to America to get this second surgery. And then you're telling me eight weeks later I have the exact same problem again? And he was like, I don't know what to say to you.
CHEN: But he mentioned that aspirin can sometimes cause nasal polyps. And this was Feit's first real clue about her illness. It's called aspirin exacerbated respiratory disease, or AERD. Doctor Tanya Laidlaw.
TANYA LAIDLAW: The disease was first described in the early 1900s with some case reports of patients who had this triad of asthma, nasal polyps and these rather idiosyncratic reactions to medications like aspirin.
CHEN: Laidlaw's an immunologist at Brigham and Women's Hospital in Boston. When she started studying the disease as a research fellow, she found there just wasn't a lot of science done on it in the last century.
LAIDLAW: That translated into having very little known about how to treat the disease or treat patients with this disease.
CHEN: And nobody really knows what causes it. At first, scientists thought it could be genetic.
LAIDLAW: There's no evidence to suggest that it's directly inheritable.
CHEN: And then they thought, well, maybe it's something in your environment.
LAIDLAW: We have yet to identify any obvious environmental trigger or infectious trigger for the disease.
CHEN: The symptoms sort of look like an allergy. But it's not an allergy. People just become very sick for seemingly no reason. Almost all the patients lose their sense of smell and taste. And then when they take a painkiller like aspirin or ibuprofen, all the symptoms suddenly get much, much worse. The reaction can be fatal. The reason for this is also unclear. It just so happened that Allison Feit's mother saw a presentation about the disease that Doctor Tanya Laidlaw put online. And she sent it to her daughter.
FEIT: And I was like, I have all these symptoms.
CHEN: Except one. Feit she knew she had asthma nasal polyps. But she didn't know if she had the third symptom - that dangerous reaction to painkillers like aspirin. So her doctor decided to test her. He gave her a fifth of a pill of aspirin, just to see what happened.
FEIT: Forty-five minutes later, I'm sitting in this, you know, hospital waiting room coughing, sweating. And my blood pressure - it just, like, spiked. And they were like, OK, stop. (Laughter). Give her medicine. Give her medicine, you know. She has the disease.
CHEN: (Laughter). But it just felt so good to just - to know, like, what it was, like to have a name to it.
FEIT: Oh, my gosh. It felt so good. Like, I started, like, tearing up in this doctor's office, like, mid-horrible reaction - like, yes.
CHEN: But there was just one problem. Feit would need a treatment called aspirin desensitization. And her doctor had never done it before.
FEIT: He was just like, I don't feel comfortable doing it. And he was like, I don't think you're going to find a doctor in Asia that is. So I was like, man.
CHEN: Feit left Thailand again and went to Tanya Laidlaw's clinic in Boston to get the procedure.
FEIT: She was just kind of like, so basically in order to fix this really bad allergy that you have to aspirin, I'm going to give you a lot of it. And I was like, that sounds terrifying.
CHEN: Feit took aspirin in increasing doses over the course of a day, and it worked. She's been feeling a lot better since the treatment.
FEIT: Since last January, I've had one sinus infection - one.
CHEN: That's awesome.
FEIT: It's amazing. And prior to that, I probably had one at least once a month.
CHEN: Nobody knows why this works. But there are lots of people with the disease. And Laidlaw's frustrated with the lack of awareness.
LAIDLAW: We are very still worried that we are missing a large portion of these patients who don't know that they have the disease.
CHEN: She thinks there might be as many as 1.5 million Americans with AERD. By her estimates, at least 20 percent of those are undiagnosed. Angus Chen, NPR News.
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