She spent nearly 20 years believing she had MS. Then her diagnosis changed.
Updated on: October 31, 2026 / 9:50 AM EDT / CBS News
TL;DR
- DeMonica Amerson lived with a misdiagnosis of multiple sclerosis (MS) for nearly 20 years.
- She transitioned from daily MS injections to monthly infusions and later port-administered medication.
- A significant health event in 2019 prompted further medical investigation, leading to a revised diagnosis of neuromyelitis optica spectrum disorder (NMOSD).
- Studies show that 15-20% of individuals diagnosed with MS are later found not to have the condition.
- Actor Christina Applegate has also publicly shared her experience of being misdiagnosed with MS for approximately five years.
- Misdiagnosis often occurs due to the complexity of MS symptoms and the interpretation of brain scans and other markers.
- NMOSD shares similar symptoms with MS but can be more severe and is often identified by a specific antibody in the blood.
- Amerson is now advocating for awareness of NMOSD and focuses on moving forward positively.
- New diagnostic criteria for MS are being developed to reduce the risk of misdiagnosis.