Paroxysmal motor disorders of sleep misdiagnosed as epilepsy

Abstract

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. 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. 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%). 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. Inpatient Video-EEG Monitoring Unit, Epilepsy Unit, University Hospital Virgen del Rocío. Seville, Spain.