Panayiotopoulos syndrome

Overview

  • Panayiotopoulos syndrome predominantly occurs in children between the ages of 3 to 6 years (but range is 1-14 years).
  • The seizures typically include prominent autonomic features such as vomiting, pallor, incontinence, hypersalivation, and dilated pupils. These seizures are usually prolonged (5 to 10 mins) and can lead to status epilepticus.
  • The EEG can have multifocal high amplitude sharp and slow complexes, more commonly found in the occipital lobes.
  • Prognosis is excellent with risk of later epilepsy returning to that of the normal population.
  • Anticonvulsant therapy may not be indicated if seizures are brief, infrequent, and do not compromise patient. Those children with prolonged seizures or compromised cardiovascular features may require urgent medical assistance. An emergency plan is required.

According to the NICE Guideline: The Epilepsies:

  • The seizure type(s) and epilepsy syndrome, aetiology, and co-morbidity, should be determined.
  • If there is diagnostic uncertainty, individuals should be referred to tertiary services soon (within 4 weeks) for further assessment.

Demographics

Age at onset

  • ~1-14 years (3 to 6 years in ~74% of cases).

Genetics

  • Febrile seizures in ~17%.
  • Occurrence in other siblings is exceptional.

Signs | Symptoms

Seizure semiology
The seizures mainly manifest with autonomic symptoms. Emesis (vomiting) is the most common symptom (70% to 80%), but is not always present or apparent.

Others include pallor, incontinence of urine and faeces, mydriasis or miosis, cardio-respiratory irregularities, hypersalivation, thermoregulatory changes, and cephalic sensations.

Ictal syncope (unresponsive and flaccid) is common.

  • Behavioural ictal features include irritability or quietness, patient looks or feels unwell.
  • Consciousness is commonly intact at onset but severely disturbed in the seizure progression.
  • Other ictal features include eye deviation (60% to 80%); half progress to hemiconvulsions or generalized convulsions. 
  • Visual hallucinations are rare (10%) and do not appear at the onset.
  • Duration is long, typically 5 to 10 mins; nearly half have autonomic status epilepticus (>30mins).
  • Often the clinical features are indistinguishable from encephalitis in the acute phase. Children with Panayiotopoulos Syndrome often recover completely after their post-ictal phase which would be atypical for encephalitis or other brain pathologies.


Timing

  • 2/3 of the seizures occur in sleep.

Neurological and mental state

  • Normal

Differential diagnosis

  • Encephalitis, atypical migraine, syncope, gastroenteritis, unspecified epilepsy.
  • Symptomatic occipital epilepsies.
  • Occipital lobe seizures can be symptomatic of Coeliac Disease.

Investigations

EEG

  • Multifocal spikes are more common; occipital spikes +/- extra-occipital spikes predominate.
  • 1/10 have a normal EEG.

Neuro Imaging

  • Needs careful consideration as the seizure semiology of Panayiotopoulos Syndrome is not easily distinguished from that of a symptomatic occipital epilepsy.

 

Prognosis

  • Excellent.
  • Remission within 1 to 2 years, 1/3 of patients have a single seizure, only ~10% have >10 seizures; 1/5 (21%) may develop other seizure types, mainly Rolandic (13%).
  • Risk for later epilepsy is the same as in normal population.
  • In very exceptional cases, autonomic seizures may be life-threatening, such as cardio-respiratory arrest.

Management

  • Continuous AED therapy is not always recommended for children with a single seizure or brief seizures.  A careful discussion is required regarding pros and cons of treatment with consideration of cardiorespiratory and convulsive features in semiology.     
  • Prolonged seizures (status epilepticus) are possible and management should be discussed.
  • Treatment options include carbamazepine and valproate (not in women of child bearing age).

 
Discussion with family

 
Resources

Epilepsy Action (UK) have information for Parents on Panayiotopoulos Syndrome

References

  • Panayiotopoulos CP. The epilepsies: Seizures, syndromes and management: Based on the ILAE classifications and practice parameter guidelines. Chipping Norton, Oxfordshire: Bladen Medical Publishing; 2005.
  • Roger J, Bureau M, Dravet C, Genton P, Tassinari CA, Wolf P, editors. Epileptic syndromes in infancy, childhood and adolescence (4th ed).  Montrouge, France: John Libbey Eurotext Ltd ; 2005.