Clinical features of epilepsy with pervasive developmental disorder

PurposeTo clarify the clinical features of patients with epilepsy and pervasive developmental disorder (PDD). Methods: We examined 12 outpatients with epilepsy as well as PDD at Seiai Rehabilitation Hospital. Results: The patients comprised 7 males and 5 females. The initial neurological symptoms appeared between 5 months and 4 years of age. The interval between the initial neurological symptoms/developmental delay and seizure onset ranged from several months to twenty years. The seizures started at 10–19 years of age in 8 out of the 12 cases. The types of seizures were astatic-drop in 2 cases, tonic-to-astatic in one, atypical absence (decreased consciousness) and generalized tonic clonic seizures (GTCS) in 3 cases, GTCS in 4 cases, or myoclonic and psychomotor in 2 cases. The mental development distributed from normal to extremely severe retardation. Paroxysmal abnormalities on eegs were focal at the frontal area in 7 cases (58%) and other findings in 5 cases. Presumptive risk factors were prenatal in 6 cases (family history for PDD in 1 case, for epilepsy in 1, twin pregnancy in 2 cases, and other in 2 cases), perinatal in 2 patients, postnatal in 1, and unknown in 3 cases. Conclusions: The seizures occurred most frequently after the onset of neurological symptoms or developmental delay. The frontal lobe dysfunction was associated with seizure onset in 58% of the cases based on the EEG findings. The risk factors were prenatal in 50% of the cases.