Panayiotopoulos Syndrome. Early Onset Benign Childhood Seizures with Occipital Spikes.
Incidence
Prevalence is 13% in children 3 to 6 years old with epilepsy and 6% in the 1 to15-year age group of people with epilepsy. In the general population, 2 to 3 per 1000 children may be affected.
Clinical Characteristics
Panayiotopoulos syndrome (PS) is an early childhood related idiopathic benign susceptibility to focal seizures. The seizures are mostly autonomic and may result occasionally in status epilepticus. It is considered an epileptic syndrome. Nearly half of these seizures last between 30 min and 7 hours. The patient usually complains of feeling sick, then becomes pale and usually vomits multiple times. During this phase consciousness is preserved. Later, the patient becomes cyanotic, may have flushing and dilated pupils. Eventually there is impairment of consciousness, deviation of the eyes, and deviation of the head may occur. Speech arrest and visual hallucinations are much less common. There may be ictal syncope, hypersalivation, and occasional hemifacial spasms. Eyelid jerks and myoclonic jerks occur rarely. Headaches occur at times. About 20% of the seizures end with hemiconvulsiones, Jacksonian march or generalized convulsions. Two-thirds of seizures begin during sleep. PS is likely genetically determined, but there is usually no family history of similar seizures, though siblings with PS or PS and Rolandic epilepsy have been reported. There is a high prevalence of febrile seizures, about 17%. Also, there may be a high incidence of abnormal birth deliveries. EEG commonly (90%) reveals functional, mainly multifocal, high amplitude, sharp and slow wave complexes. There is great EEG variability of focal spikes at various locations. All brain regions are involved though the posterior predominate. Similar shape repetitive multifocal spike-wave complexes may be a characteristic features when they occur (19%). They are probably pathognomonic of the syndrome if recorded from otherwise normal children with a few epileptic seizures. Spikes are usually of high amplitude and morphologically similar to the centro-temporal (Rolandic) spikes. Brief generalized discharges of slow waves intermixed with small spikes may occur either alone (4%) or, more often, with focal spikes (15%). The EEG spikes may be stimulus sensitive; occipital paroxysms are commonly (47%) activated by the elimination of central vision and fixation whereas centrotemporal spikes may be elicited by somatosensory stimuli. Occipital photosensitivity is a rare finding. The background EEG is usually normal, but diffuse or localized slow wave abnormality may also occur in at least one EEG of 20% of patients, especially postictally. EEG abnormalities, particularly spikes, may persist after clinical remission for many years until mid-teens. PS is a benign condition despite the high incidence of autonomic status epilepticus. One-third of patients have only a single seizure, half have 2–5 seizures and only 5% have more than 10 seizures, which can sometimes be very frequent. However, the prognosis is favorable. Remission commonly occurs within 1–2 years from onset. The risk of developing epilepsy in adult life is probably no more than that in the general population. However, 20% of patients may develop another type of infrequent, usually Rolandic (13%), seizures during their childhood and early teens. However, these seizures remit before the age of 16 years. Despite its benign course, some seizures of PS may occasionally manifest with potentially fatal autonomic symptoms, such as cardiorespiratory arrest. Brain CT and MRI are normal. Continuous anticonvulsant therapy is not recommended for children with one or brief seizures. Most clinicians treat recurrent seizures with carbamazepine or Valproic acid if needed. Rectal diazepam is prescribed for prolonged seizures.
Precipitants
In two thirds (66%) of affected children, seizures occur only during sleep and particularly the first hour of sleep.
Provocation Tests
None.
Diagnostic Procedures
It is a clinical diagnosis. The diagnosis of early-onset benign partial epilepsy with occipital paroxysms or Panayiotopoulos syndrome is made on a detailed account of the child’s symptoms. Important features in making the diagnosis are: the episodes usually occur during sleep and are nearly always accompanied by autonomic features and vomiting. The child’s age is also important, as most seizures occur in young children.