PMID 20301774


PRICKLE1-related progressive myoclonus epilepsy (PME) with ataxia is characterized by myoclonic seizures (lightning-like jerks), generalized convulsive seizures, varying degrees of neurologic decline especially manifest as ataxia, and normal intellectual abilities. Onset of symptoms is between ages five and ten years. Action myoclonus may affect the limbs or bulbar muscles, sometimes with spontaneous myoclonus of facial muscles. Marked dysarthria may occur. Seizures can be myoclonic or tonic-clonic and are often nocturnal. PRICKLE1-related PME with ataxia is suspected in individuals with characteristic clinical findings and confirmed by identification of biallelic pathogenic variants in PRICKLE1. Treatment of manifestations: Treatment of epilepsy involves antiepileptic drugs (AEDs) including valproic acid, clonazepam, zonisamide, piracetam, and levetiracetam. Ataxia may require assistive devices or eventually wheelchair. Consultation with a speech pathologist may be helpful. Surveillance: Routine follow-up to ensure effective seizure control and monitor for changes in symptoms. Agents/circumstances to avoid: Phenytoin, carbamezapine, and oxycarbazpine. PRICKLE1-related PME with ataxia is inherited in an autosomal recessive manner. At conception, each sib of an affected individual has a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier. Carrier testing for at-risk relatives and prenatal diagnosis for pregnancies at increased risk are possible if the pathogenic variants in the family have been identified.