The sudden onset of muscle weakness on one side of the face can be scary, to the point that it sends people rushing to the ER. This muscle weakness can be caused by a number of conditions. But when it's Bell's palsy, ER doctors usually diagnose it correctly.
A recent study looked at ER records for patients who were diagnosed with Bell’s palsy to see if there were any misdiagnosed cases.
The results showed that 99 percent of patients were correctly diagnosed with Bell’s palsy in the ER.
Jahan Fahimi, MD, MPH, of the Department of Emergency Medicine at the University of California San Francisco, led a team of researchers to look into whether Bell’s palsy usually gets diagnosed correctly in the emergency room (ER).
Bell’s palsy is characterized by the sudden onset of muscle weakness on one side of the face, which develops to a certain degree of paralysis over the course one day to one week.
Roughly 15 people out of every 100,000 experience Bell’s palsy at some point. About 85 percent of Bell’s palsy patients experience some level of recovery, and many patients have a full recovery.
Bell’s palsy can last any where between a few weeks to an indefinite amount of time.
To the naked eye, the face of a person with Bell’s palsy will appear slack on the effected side. The muscle weakness associated with Bell’s palsy can make it hard to close the eye or blink, to smile or to wrinkle the forehead.
Other internal symptoms can include difficulty making tears, overly sensitive hearing, changes in taste buds on the affected side and eye watering during salivation.
Typically, healthcare providers treat Bell’s palsy with a round of corticosteroids and antivirals, which shows improvement in some cases.
For this study, the researchers looked through California’s Office of Statewide Health Planning and Development from 2005 to 2011 for people diagnosed with Bell’s palsy in the ER. They found 43,979 patients with a median age of 45.
The researchers also checked medical records for the 90 days following each patient’s Bell’s palsy diagnosis to see if any other medical conditions could explain the facial paralysis.
These other medical conditions included stroke, brain bleed, brain tumor, central nervous system infection, Guillain–Barré syndrome, Lyme disease, otitis media/mastoiditis, or herpes zoster (shingles).
After 90 days, only 356 patients (0.8 percent) were diagnosed with one of the other medical conditions. And 40 percent of those were diagnosed within seven days of the Bell’s palsy diagnosis.
Overall, 85 percent of the other medical conditions responsible for the facial paralysis were stroke, herpes zoster, Guillain-Barré and otitis media.
People with private insurance were less likely to be misdiagnosed by 0.65 times compared to people without private insurance.
"Emergency providers have a very low rate of misdiagnosing Bell’s palsy," the study authors wrote.
"Bell's palsy is one of those conditions that can scare the heck out of the patient because the first thing they will think of is stroke," Chris Galloway, MD, told dailyRx News.
“Fortunately, Bell's palsy has a different cause, clinical course, and outcome. Our job as physicians is to get the right diagnosis, minimize unnecessary diagnostics, and institute treatment while reassuring the patient," said Dr. Galloway, who was not involved in this research.
"This article attests to the skill of emergency physicians in making the correct diagnosis of Bell's palsy through history and physical exam alone," said Dr. Galloway.
This study was published in July in Annals of Emergency Medicine.
Cornell Clinical and Translational Science Center provided grant support for this project.