Distinguishing between epileptic and nonepileptic paroxysmal events poses a diagnostic challenge.1 Nonepileptic paroxysmal events (NEPEs) are defined as brief episodes, usually with an abrupt onset and ending, caused by abnormal cerebral activity of varying etiology and not associated with epileptiform discharges.2

The main objective of the study was to describe the characteristics of patients with NEPEs that visited a pediatric emergency department and calculate the percentage of patients with paroxysmal events diagnosed as NEPEs. We conducted a single-center, cross-sectional, retrospective and descriptive study between 2021 and 2023, including previously healthy patients aged less than 18 years who sought care for a paroxysmal episode. We excluded patients with fever or symptoms suggestive of infection.

We collected data on the following variables: age, sex, type of NEPE, precipitants, neurologic examination, performance of electroencephalogram/video electroencephalogram, discharge destination, unscheduled early revisit (repeat visit to the emergency department for the same reason within 72 h), discharge destination after revisit, and recurrence in the following 12 months. The statistical analysis was conducted with the software package Stata, version 17. The study was approved by the ethics committee of the hospital (R-0027/25).

Of the 398 patients who sought care for a paroxysmal event, 297 (74.6%) received a diagnosis of NEPE, 51 (12.8%) of epileptic seizures, and 50 (12.6%) of syncope or other disorders.

Table 1 presents the characteristics of patients who received a diagnosis of NEPE. More diagnostic tests were performed in patients aged 0–24 months compared to children aged more than 24 months (P = .01), with no significant differences according to the type of NEPE (P = .19) or the findings of the neurologic examination (P = .20). Table 2 presents the age distribution of the different types of NEPE. Neurodevelopmental abnormalities were not detected during the follow-up.

In this case series, NEPEs were six times more frequent than epileptic seizures. Although this proportion is lower compared to the previous literature,1,3,4 in which NEPEs are reported as being up to 10 times more frequent, it was still high, probably due to the broad range of physiological, behavioral and psychogenic conditions that can manifest with paroxysmal features in children, many of which are benign and normal during neurologic development.

The age distribution was consistent with the previous literature,1,5 with a higher prevalence in the first two years of life. This could be related to the immaturity of the central nervous system and the response to triggers such as stress, frustration, posture changes or sleep disturbances.6

With regard to the clinical features, events involving movement disorders were most prevalent in every age group, particularly motor tics and benign sleep myoclonus, in agreement with the literature.5 These episodes are more challenging to diagnose due to their similarities with epileptic seizures and frequently lead to performance of diagnostic tests. We found no significant differences between age groups in the frequency distribution of the types of NEPE, except for abnormal eye or head movements, which were more common between ages 1 and 23 months.

A small percentage of cases (2%) were associated to functional neurologic disorders, predominantly in adolescents with a history of psychosocial stress or psychiatric disorders. A possible explanation for this low incidence, which is probably underestimated, is that the sample only included previously healthy patients with no known comorbidities.

None of the patients that received a diagnosis of NEPE experienced neurologic complications during the subsequent follow-up, which confirms the benign and self-limiting nature of NEPEs, with absence of recurrence in the 12 months following the visit in approximately 85% of patients. In spite of this, diagnostic tests were performed in more than two-thirds of these patients, with a higher frequency in those aged less than 2 years (≈50%) compared to older children (≈30%). This reflects the difficulty of diagnosing these events in the emergency care setting, which is affected by the complexity of the differential diagnosis, the uncertainty regarding their etiology and the anxiety of the family.

In this context, it is worth noting that training in pediatric emergency care focuses mainly on recognizing and treating epileptic seizures, given the associated morbidity, while training in NEPEs is limited despite their higher prevalence. Greater knowledge about NEPEs would make it possible to optimize the use of resources and guide management according to the underlying cause, which in some cases may require psychological intervention.

This study has limitations intrinsic to its retrospective design and the wide age range of children in the sample.

In our area, NEPEs are more prevalent than epileptic seizures among healthy children who present in the emergency department with a paroxysmal event. In consequence, improving training on this subject is of the essence, as a thorough history-taking and neurologic examination are key to their diagnosis and enable the optimization of resources.