Paroxysmal motor disorders of sleep misdiagnosed as epilepsy

Introduction The diagnosis of paroxysmal events represents a significant challenge for the clinician. The differentiation of sleep disorders from epileptic seizures is often a cause for concern. Diagnostic error or uncertainty is not an uncommon situation. Here we review the number of patients diagnosed of drug-resistant epilepsy, admitted in a video-EEG monitoring (VEM) unit, which had actually an unrecognized sleep disorder. Materials and methods Data from a consecutive cohort of patients diagnosed of refractory epilepsy and admitted over a 1-year period to the inpatient VEM unit in a tertiary referral hospital were retrospectively analyzed. The preadmission diagnosis and management by the referring neurologist was compared with the diagnosis and management after the VEM. Results Of 52 patients, 23 (44%) were admitted for diagnostic evaluation and 29 (56%) for a presurgical workup. Mean evaluation period was 3.4 days. In 19 (36%) the diagnosis was clarified as a result of the VEM admission, with the greatest change being an increase in the pseudoseizures diagnosis group (6% to 31%), the generalized seizures diagnosis group (5–11%) and the paroxysmal motor disorders of sleep diagnosis group (0–4%). Conclusion The results of this study demonstrate that many patients with a sleep disorders are misdiagnosed of epilepsy. Future long-term cost-benefit studies of the treatment changes resulting of the correct diagnose would be necessary. Acknowledgements Inpatient Video-EEG Monitoring Unit, Epilepsy Unit, University Hospital Virgen del Rocio. Seville, Spain.