Misdiagnosis in JME: Still a problem after 17 years?

Juvenile myoclonic epilepsy (JME) is one of the most common and recognizable idiopathic generalized epilepsy with its characteristic clinical and EEG features. We think despite the well defined diagnostic criteria, and increasing awareness, misdiagnosis in JME may still be a problem. The present study aims to determine misdiagnosis in JME and to compare the results with our previous study reported in 1998.

Two hundred JME patients examined at epilepsy outpatient clinics of Bakirkoy Prof. Dr. Mazhar Osman Training and Research Hospital for Psychiatric, Neurologic and Neurosurgical Diseases between the years 2014-2015 were enrolled. Medical records of all patients were evaluated retrospectively; demographical, clinical and electrophysiological data and causes of misdiagnosis were collected from chart reviews.

Of 200 JME patients, 49 were misdiagnosed at first medical evaluation. The most common presenting seizure types were generalized tonic clonic seizure and myoclonia in misdiagnosed patients and correctly diagnosed patients, respectively. EEG revealed generalized spike wave and polyspike-wave discharges in 52% of the misdiagnosed patients. Unfortunately the physician was a neurologist in 87.8% of cases with misdiagnoses. Nearly half of 49 misdiagnosed patients were prescribed an inappropriate antiepileptic drug, and the other half were prescribed none.

Comparing our new results with the ones in 1998, misdiagnosis rate was less and time to put a correct diagnosis was shorter. However, proper diagnosis at first sight is still a problem among neurologists even the typical EEG changes are present.