Diagnosing Is Harder Than It Looks

I feel for Christina Applegate (@1capplegate). For five years she was a warrior for people with MS, but on October 20 she told her podcast listeners she had been misdiagnosed. The symptoms are still there, and some are worse. She says she's back at square one.

I don't think her doctors were careless. No single test confirms MS, and plenty of people without the disease have spots on their MRI. So neurologists look for damage that shows up in separate parts of the nervous system at different times, then rule out the imposters with more scans and lab work. Cedars-Sinai neurologist Dr. Marwa Kaisey told Applegate's podcast that her research found nearly one in five people are misdiagnosed with MS.

A 2014 study in BMJ Quality & Safety estimated that diagnostic errors in outpatient care affect about 12 million US adults a year, roughly 5%. That count only includes missed chances to reach the right diagnosis with the evidence available. Someone whose illness current tools can't identify isn't in it. The National Academies concluded in 2015 that most people will experience at least one wrong or delayed diagnosis in their lifetime.

I see too many articles about patients who feel ignored or gaslit because their physicians had no explanation to offer. A doctor who says "I don't know yet" and orders the next test is doing the job right. But a shrug with no follow-up date feels like a brush-off.

By her own account, Applegate had symptoms for six or seven years before her diagnosis. She told Good Morning America in 2024 that her leg would buckle while she was filming, and she blamed it on being tired, dehydrated, or the weather. Months passed between episodes, so she didn't think much of them. When her toes began to tingle in early 2021, she got tested.

Until now, Applegate had an explanation for why her days were hard. Now she doesn't. She still uses a wheelchair at the doctor's office because she can't walk from the car to the room. When her doctor walked in and said, "Congratulations, you don't have MS," nothing changed. In Applegate's words, "Nothing magical happened."

I hope her doctors find a name for it.