Maeike Zijlmans

Objective New‐onset seizure‐like events (SLEs) are common in children, but differentiating between epilepsy and its mimics is challenging. This study provides an overview of the clinical characteristics, diagnoses, and corresponding etiologies of children evaluated at a first seizure clinic (FSC), which will be helpful for all physicians involved in the care of children with SLEs. Methods We included 1213 children who were referred to the FSC of a Dutch tertiary children's hospital over a 13‐year period and described their clinical characteristics, first routine EEG recording results, and the distribution and specification of their eventual epilepsy and non‐epilepsy diagnoses. The time interval to correct diagnosis and the diagnostic accuracy of the FSC were evaluated. Results “Epilepsy” was eventually diagnosed in 407 children (33.5%), “no epilepsy” in 737 (60.8%), and the diagnosis remained “unclear” in 69 (5.7%). Epileptiform abnormalities were seen in 60.9% of the EEG recordings in the “epilepsy” group, and in 5.7% and 11.6% of the “no epilepsy” and “unclear” group, respectively. Of all children with final “epilepsy” and “no epilepsy” diagnoses, 68.6% already received their diagnosis at FSC consultation, and 2.9% of the children were initially misdiagnosed. The mean time to final diagnosis was 2.0 months, and 91.3% of all children received their final diagnosis within 12 months after the FSC consultation. Significance We describe the largest pediatric FSC cohort to date, which can serve as a clinical frame of reference. The experience and expertise built at FSCs will improve and accelerate diagnosis in children with SLEs. Plain language summary Many children experience events that resemble but not necessarily are seizures. Distinguishing between seizures and seizure mimics is important but challenging. Specialized first‐seizure clinics can help with this. Here, we report data from 1213 children who were referred to the first seizure clinic of a Dutch children's hospital. One‐third of them were diagnosed with epilepsy. In 68.8% of all children—with and without epilepsy—the diagnosis was made during the first consultation. Less than 3% were misdiagnosed. This study may help physicians in what to expect regarding the diagnoses in children who present with events that resemble seizures.