Prevalence of Seizure in PKU: An Analytic Historical Study

Phenylketonuria (PKU) is an autosomal recessive metabolic genetic disorder characterized by a deficiency in the hepatic enzyme phenylalanine hydroxylase(PAH) which can cause problems with brain development, leading to progressive mental retardation, brain damage, and seizures. In this study we evaluated the frequency of seizure, EEG abnormality and behavioral disorders.Materials & MethodsIn this case study, 94 PKU children aged between 1 month and 23 years who were referred to Mofid children Hospital between 2009 and 2010 were enrolled. Patients were age and sex matched. Statistical tests were used for comparing patients’ data.ResultsThe mean age of patients was 8.4 years. Parents were relatives in 80.9% of the cases (76 patients). Of all, 43% (45 patients) had seizure but EEG was abnormalonly in 81% of them (35 patients out of 43 patients). Totally, EEG was abnormal in 67% of the cases (63 patients) of whom 44.4% (28 patients of 63 patients) did not have seizure. Therefore, there was a significant relationship between seizure and EEG abnormality. The phenylalanine level ranged from 8mg/dL to 50mg/dL (mean: 18.88 mg/dL) at the time of diagnosis and from 0.4mg/dL to 18mg/dL (mean: 7.37mg/dL) at the time of evaluation. On the other hand, we observed abnormal behaviors in all EEG abnormalities and there was a significant relationship between EEG abnormality and behavioral disorders.ConclusionIn our study, the prevalence of seizure was less than EEG abnormality and there was a significant relationship between EEG abnormalities and behavioraldisorders in patients with Phenylketonuria regardless of seizure.The authors believe that treatment of EEG abnormalities may lead to the correction of behavioral disorders in these patients.