The many causes of sore throat: Diagnostic pearls
© 2014 Roy Benaroch, MD
Sallie wrote in about what to do when a common complaint is caused by an uncommon diagnosis. Her child was having a lot of sore throats, one after another, and saw a lot of doctors before the final diagnosis was reached. It’s a good question, and a golden opportunity to talk about keeping your mind open to new ideas, especially when things aren’t progressing as expected.
Pearl #1: Common diagnoses are common
Common things happen commonly—or, in other words, when someone is sick, it’s much more common for it to be a common illness than an uncommon illness. 90% of sick visits to pediatricians are for one of 5 diagnoses. Those rare things you read about on the internet? They don’t happen much. That’s why they’re called “rare.”
For people with a sore throat, the very common diagnosis is a viral infection that will get better. These infections begin with a sore throat, then turn into a stuffy nose and cough. There may be some fever and aches. We’ve all had this, multiple times. It’s an upper respiratory infection, and it’s the single most common driver of pediatric visits. And we still don’t have any effective treatment for it. Humbling.
One other common diagnosis that causes sore throat is a strep infection, or “strep throat.” (It’s never “strept throat.” I have no idea where that extra “t” comes from.) Strep is less common a viral sore throat, but it’s still fairly common. So many people with sore throat (especially when accompanied by fever and red tonsils and enlarged lymph nodes) get a strep test to see if it’s viral or strep.
Sore throats can be caused by other common infections, too: influenza, mononucleosis, or laryngitis. These usually cause other symptoms that make the diagnosis easy (or easy-ish), but sometimes they don’t… which leads us to the next pearl:
Pearl #2: It is much more common for common diseases to present uncommonly, than for uncommon diseases to present at all
Most people with influenza will have fevers and aches, in addition to sore throat; most people with croup or laryngitis will have hoarse voices or a barky cough; most people (at least teenagers) with mono will have fevers and tiredness in addition to their sore throat. But, again, not always. And these common conditions will sometimes fool you by not causing every expected symptom.
Or: let’s say a child has frequent sore throats—but they don’t seem to be viral or bacterial. That is, they’re not accompanied by fevers or runny noses or cough, and strep tests come back negative. What’s likely to be going on? It could be a genuinely weird, uncommon diagnosis—or, more likely, it could be a common thing that’s presenting in an odd manner. For instance, GERD (reflux) is common, and usually presents with heartburn or spitting up or an obvious sensation of food coming up into the mouth. But sometimes, it can cause sore throats.
Pearl #3: Even though they’re rare, if you keep looking you’ll find uncommon diagnoses Pearls #1 and #2 pretty much discount rare diagnoses, because they’re rare. But: every once in a while, those rare things do happen. But if doctors stop looking for them, they’ll never find them. Nearly everyone has a common diagnosis—except those rare people who don’t. And no one comes into the office with a stamp on their forehead that says “Think! I have something rare!”
Chronic or recurrent sore throats can rarely be caused by, among other things, a mass or tumor in the throat; or by nerve damage that prevents the vocal cords from operating normally; or by irritation from a toothpaste or mouthwash. Or from yelling frequently, especially if you’re not yelling correctly (yes, there’s a right way to yell that will cause less damage to your throat. Some people don’t do it right.)
One quite-rare example of a cause of chronic or recurrent unexplained throat pain is Eosinophilic Esophagitis (EE). This is an inflammatory condition that usually causes mostly esophageal symptoms (symptoms similar to heartburn, or to a feeling of food getting “stuck.”) Rarely, this uncommon condition can present in a very uncommon way: with sore throat. Which is actually, after a prolonged diagnostic journey, what Sallie’s son turned out to have.
The only way to diagnose EE is with a biopsy—you have to look down there, in the throat, with a scope, and get some tissue. Not everyone with sore throats needs that kind of evaluation. But we need to keep in mind that at least some kids with common complaints might just have something genuinely rare going on. If we don’t look, we’ll never see.
Hey! If you liked thinking about this—the way doctors think about making diagnoses, about looking for needles in haystacks and thinking critically about clues and medical mysteries, you might enjoy my lecture series at The Great Courses! It’s called “Medical School For Everyone”, and it’s a series of 24 medical case studies for laymen to try to figure out. I’ll give you the clues! Check it out through that link, and let me know what you think!