Panayiotopoulos syndrome: epidemiological and clinical characteristics and outcome

A reappraisal of interictal EEG characteristics in self-limited epilepsy with autonomic seizures, formerly known as Panayiotopoulos syndrome or early-onset benign occipital epilepsy

PURPOSE

In the 2022 New International Classification of Epilepsy Syndromes, self-limited epilepsy with autonomic seizures (SeLEAS), formerly known as Panayiotopoulos syndrome is recognized as an electroclinical syndrome that is clinically characterized by autonomic seizures and electroencephalographically by multifocal EEG foci. EEG studies were reviewed herein and the suitability of the EEG definition to characterize SeLEAS was assessed.

METHODS AND RESULTS

The EEG findings of SeLEAS studies published to date were reviewed and typical sites of EEG foci and their evolutionary changes with age were analyzed. Although previous studies investigated the details of interictal EEG characteristics in a sufficient number of SeLEAS cases, there were few systematically analyzing cross sectional and longitudinal EEG changes except one study. Despite these limited evidence, I propose the following practical and useful EEG definition. The interictal EEG characteristics of SeLEAS are multifocal EEG foci with age-dependent predominant locations; occipital (O) at 2-5 years old, and occipital and frontopolar (synchronous and independent O and Fp spikes) at 4-7 years old and centro-parieto-temporal (CPT) at 6-10 years old. O EEG foci evolve to multifocal EEG foci with a O-Fp or CPT predominance with age and disappear by 12∼16 years old. O-Fp EEG foci may further evolve to generalized spike-wave complexes and rarely to spike-wave activated in sleep. In rare cases, the EEGs do not have epileptic EEG foci.

CONCLUSION

Interictal EEG foci in SeLAES may have different EEG patterns in terms of location and the mode of appearance depending on the age at which EEG is recorded. O-Fp EEG foci may be a specific EEG pattern indicating a diagnosis of SeLEAS.

Probability of Remission of the Main Epileptic Syndromes in Childhood

AIM

To determine the long-term probability of remission without antiepileptic treatment of common epileptic syndromes and of children without a specific syndromic diagnosis.

PATIENTS AND METHODS

All children less than 14 years old with 2 or more unprovoked seizures seen at our hospital between June 1, 1994, and March 1, 2011 (n = 680), were included and prospectively followed up until August 15, 2020. Syndromic diagnosis was made retrospectively but blinded to subsequent evolution, employing the data available at 6 months after diagnosis and under predefined operational criteria.

RESULTS

The Kaplan-Meier estimate of the probability of achieving a remission period of at least 5 years, with neither seizures nor antiepileptic treatment at 14 years was 97% for well-defined childhood epilepsy with centrotemporal spikes, 82% for uncertain childhood epilepsy with centrotemporal spikes, 85% for well-defined Panayiotopoulos syndrome, 88% for uncertain Panayiotopoulos syndrome, 93% for nonfamilial self-limited infantile epilepsy, 100% for familial self-limited infantile epilepsy, 86% for absence epilepsy, 6% for juvenile myoclonic epilepsy, 71% for cryptogenic West syndrome, 72% for patients with no associated neurologic deficits and no specific syndromic diagnosis, 65% for symptomatic West syndrome, and 40% for patients with associated neurologic deficits and no specific syndromic diagnosis.

CONCLUSIONS

The study results highlight the long-term outcomes of the main epileptic syndromes and also of the patients with no syndromic diagnosis.

Misdiagnosis and pitfalls in Panayiotopoulos syndrome

Panayiotopoulos syndrome (PS) is a frequent (6% among children of 1-15 years) and benign epileptic syndrome, characterized by predominantly autonomic symptoms (emesis, pallor, flushing, cyanosis, mydriasis/miosis, cardiorespiratory and thermoregulatory alterations, incontinence of urine and/or feces, hypersalivation, and modifications of intestinal motility) associated with simple motor focal seizures, which can be followed by secondary generalization. Panayiotopoulos syndrome can be extremely insidious, because it can mimic several condition, such as gastroenteritis, gastroesophageal reflux disease, encephalitis, syncope, migraine, sleep disorders, or even metabolic diseases. This peculiar pleiotropism should be kept in mind by child neurologists and pediatricians and general practitioners, because a wrong diagnosis may lead to inappropriate interventions. The consequences are high morbidity, costly mismanagement, and stress for children and their parents. The availability of electroencephalography (EEG) recording in pediatric Emergency Departments might be useful for a prompt and not-cost-consuming diagnosis. On the other hand, it is important to be aware of the possible, multifaceted, clinical presentations of PS and its clinical, radiological, and neurophysiological features in order to improve both recognition and management.

Panayiotopoulos Syndrome with a special emphasis of ictal semiologic features

PURPOSE

The aim was to identify the demographic, electroencephalographic findings, clinical features, especially ictal semiological symptoms of patients diagnosed with Panayiotopoulos Syndrome.

METHOD

The semiologic and EEG findings of 42 patients were reviewed. Statistical analysis was used to determine the frequencies of semiologic features and to define the symptom clusters.

RESULTS

The most common clinical features were nausea (54.8%), vomiting (50.0%), pallor (50.0%), deviation of head and eyes (45.2%), generalized seizures (35.7%), ictal syncope (33.3%) and stomach ache (26.2%). Visual manifestations which were observed in 38.9% of the patients were amaurosis, flashes of colourful lights, flashes of brightful lights, visual hallucinations and blurring of vision. Autonomic status epilepticus was observed in 21.4% of the patients. Cluster analysis of 13 most common symptoms showed a tendency toward 3 clusters. Pallor constituted a subgroup on its own whereas nausea, vomiting, deviation of head and eyes tended to occur together in the second subgroup and the third subgroup included semiologic features some of which were atypical for PS.

CONCLUSIONS

A broad spectrum of typical and atypical clinical features might be observed in patients with PS. Some of the semiologic features of PS might have tendency to occur together. Overlapping of typical autonomic features with some of the atypical features might suggest that PS, RE and ICOE-G were the constituents of the same neurobiological spectrum. Our detailed data might contribute to the awareness of a wide range of variabilites in the electroclinical features of PS.

Panayiotopoulos syndrome: a case series from Turkey

The aim of the study was to evaluate the demographic, clinical, and EEG characteristics of patients with Panayiotopoulos syndrome (PS) and the course of their illness. Thirty-eight patients followed up with a diagnosis of PS between January 2011 and December 2013 were evaluated. We found high rates of personal history of febrile convulsions, breath-holding spells, and family history of febrile convulsions, afebrile convulsion/epilepsy, migraine, and breath-holding spells. Seizures started before the age of eight in 87% of the patients, and the mean age at seizure onset was 4.6 years. Seizures were sleep-related in 81.5%, and autonomic status was seen in a third of the patients. The number of seizures was between 2 and 10 in 66% of the patients. The most common symptoms were ictus emeticus, eye/head deviation, and altered consciousness. Rolandic features were seen in 26% of the patients, and visual symptoms in 5%. Multifocal epileptiform discharges on EEG were identified in 84% of the patients. Two or more antiepileptic drugs were required in only 13% of the patients. Evolution to electrical status epilepticus in sleep and Gastaut-type epilepsy were seen in patients with more than ten seizures. The high rates of febrile convulsions, afebrile convulsions/epilepsy, migraine, and breath-holding spells in the patients and families suggest the importance of genetic factors and, perhaps, a common pathogenesis. However, the high rates of febrile convulsions and breath-holding spells in patients can be related to a misdiagnosis because of the similar symptoms. Despite its disturbing symptoms, PS is a benign epileptic syndrome requiring multiple antiepileptic drug use only in a small proportion of patients.

Idiopathic focal epilepsies

In this chapter we include a series of epilepsies with onset in pediatric age characterized by focal seizures, idiopathic etiology, normal psychomotor development, and a benign course related to the spontaneous remission of seizures without sequelae. These entities are age-dependent and seizures tend to disappear spontaneously. For these reasons often the drug treatment is not necessary. On the basis of genetic assessment idiopathic focal epilepsies can be divided into two groups: nonautosomal dominant and autosomal dominant. In the group of nonautosomal entities we include benign epilepsy with centro-temporal spikes, Panayiotopoulos syndrome, idiopathic childhood occipital epilepsy described by Gastaut, and benign idiopathic midline spikes epilepsy. Seizures are rare, sometimes prolonged, as autonomic status in Panayiotopoulos syndrome. A common feature is the presence of peculiar EEG interictal paroxysmal abnormalities. In the group with an autosomal dominant mode of inheritance we include benign familial infantile seizures and benign familial neonatal-infantile seizures. These entities are characterized by partial seizures in cluster, self-limited in a brief period during the first months of life. There are no typical interictal EEG abnormalities. In some families a mutation in SCN2A, the gene coding for the 2α subunit of the voltage-gated sodium channel, has been described.

Benign epilepsy in children

The diagnosis of benign epilepsy syndrome should meet the following criteria: age-related and self-limited; good response to medication; and no obvious neurological sequelae after seizure. However, the current concept of benign epilepsy syndrome has been challenged because of the advancements in genetic studies, neuroimaging, and molecular techniques. Many studies have revealed that the prevalence of behavioral problems and learning difficulties as well as subtle cognitive deficits is higher among patients with benign epilepsy, compared with the normal population. Here, we review updated results of these studies to show the latest and broad comprehensive knowledge of benign epilepsy in children.

Panayiotopoulos syndrome: a clinical, EEG, and neuropsychological study of 93 consecutive patients

PURPOSE

To explore the clinical, electroencephalography (EEG), neuropsychological features, and prognosis of Panayiotopoulos syndrome (PS).

METHODS

Of 1,794 children aged between 1 and 14 years referred for the first afebrile focal seizure, between January 1992 and December 2004, 93 (5.2%) had PS according to clinical criteria.

RESULTS

Age at onset ranged from 1.1 to 8.6 years, and was earlier in children with more than one seizure. Autonomic seizures followed a stereotypical onset and progression. Emesis, pallor, or flushing was almost always among the first symptoms that usually culminated in vomiting (77.4% of patients). More than half (55%) of seizures were longer than 30 min but these did not appear to affect remission and number of seizures. Interictal EEG showed great variability, with 79.5% of patients showing spikes of variable localizations and evolution over time; 16.1% had background abnormalities only, and 5.4% had consistently normal EEG studies. Onsets in five ictal EEGs were posterior or anterior-left or right. On neuropsychological testing, IQ and subtests of Wechsler Intelligence Scale for Children-Revised (WISC-R) were within normal limits, although some minor statistically significant differences were found in arithmetic, comprehension, and picture arrangement in comparison with controls. Cumulative probability of recurrence was 57.6%, 45.6%, 35.1%, and 11.7% at 6, 12, 24, and 36 months, respectively, after the first seizure. Thirty-four (58.6%) of 59 patients treated with antiepileptic drugs continued having seizures before ultimate remission.

DISCUSSION

PS is a uniform childhood susceptibility to autonomic seizures that is related to early age of development and with excellent prognosis with regard to seizure remission and neuropsychological development.

Panayiotopoulos syndrome: an important childhood autonomic epilepsy to be differentiated from occipital epilepsy and acute non-epileptic disorders

Panayiotopoulos syndrome is a common multifocal autonomic childhood epileptic disorder with significant clinical, pathophysiological and management implications. It affects otherwise normal children with onset at around 3-6 years. It is characterized by seizures, often prolonged, with predominantly autonomic symptoms and mainly ictal vomiting. EEG shows shifting and/or multiple foci, often with occipital dominance. Despite characteristic clinical and EEG manifestations Panayiotopoulos syndrome is often confused with occipital epilepsy and acute non-epileptic disorders such as encephalitis, syncope, cyclic vomiting or atypical migraine. This review aims to describe Panayiotopoulos syndrome on the basis of independent major studies and provide clinical clues for diagnosis and management.