Background: To make a diagnosis between first seizure, epilepsy and non-epileptic event is a challenging clinical exercise for many physicians as it may lead to different therapeutic implications. We ascertained the agreement between the initial diagnosis at the accident and emergency(A&E) department and the final diagnosis following in-patient neurological evaluation of seizure disorders.
Method:A prospective observational study between 4/04 and 6/05 in a regional hospital in Hong Kong recruited 1,701 patients from A&E to neurology/medical wards with initial diagnoses/labels matching any one of twelve pre-defined keywords which were categorised as either “seizure-specific” or “non-specific”.
Results: Among the 1,170 patients with “non-specific” initial diagnoses/labels, 58 (5%) were finally diagnosed to have had first seizures or epilepsy. Among 531 patients with “seizure-specific” initial diagnoses/labels, 27 (5.1%) were subsequently diagnosed to have had non-epileptic events. The kappa-value for agreement between the initial and final diagnosis was 0.88. Of the 154 patients with final diagnosis of first seizure, 34 (22%) had “non-specific” initial labels. Among these patients, components of the evaluation contributing to revision of diagnosis included retrieval of witness accounts(47%), epileptiform discharges on electroencephalogram(EEG)(47%), short-term monitoring in patients suspected of acute symptomatic seizures(28%) and panel discussion of cases(22%).
Conclusion: There was generally high degree of agreement between the initial and final diagnosis, but first seizures were often missed initially. Careful history taking, judicious use of EEG, selective short-term monitoring and liaison with specialists are important for reaching an accurate diagnosis.
- first seizure
- interrater reliability