A case of Lafora's disease associated with cardiac arrhythmia.

Progressive myoclonic epilepsies are rare, genetically transmitted diseases characterized by epileptic seizures, myoclonus, and progressive neurologic deterioration. Unverricht-Lundborg disease, Lafora's disease, neuronal ceroid lipofuscinosis, mitochondrial disorders, and sialidosis are included in this group. Lafora's disease is a progressive disorder of the central nervous system with onset in the late first or second decade of life and is inherited in an autosomal-recessive pattern. The first clinical manifestation is generalized tonic-clonic seizures, myoclonus, or both, usually seen between the ages of 11 and 18 years. The other clinical manifestations are progressive dementia and limb ataxia. Diagnosis is based on showing the typical inclusions in the brain, liver, skin, or muscle tissue specimens. The case of a 6-year-old male patient, who was admitted with the clinical findings of third-degree atrioventricular block and dementia and eventually diagnosed with Lafora's disease, is presented.