The importance of neonatal screening in phenylketonuria and the influence of specific nutritional therapy over psychomotor development

Abstract

Introduction: Phenylketonuria (PKU ) is an autosomal - recessive disorder caused by phenylalanine – hydroxylase deficiency.Management and control of phenylalanine (Phe) levels through dietary intake remains the standard treatment in PKU. The aim of this study was to determine therelationship between early diagnosis (neonatal screening) Associated with early treatment and a favorable prognosis in PKU patients (prevention of neuro – motor delay). Material and Methods: The study is a retrospective analysis of 15 participants’ medical records (PKU patients aged 5 months to 10 years of age), who have been diagnosed in the period 01.01.2010 - 06.01.2015, at the ’’Saint Mary” Emergency Hospital for Children, Iasi. Values of phenylalanine ( Phe ) obtained at neonatal screening, age at the moment of diagnosis,treatment, family compliance and psychomotor development were studied. Results: All 15 participants presented elevated Phe values at the initial screening (range between 3.47 to 41.09 mg % ).With the exception of two late diagnoses ( at that time this screening program was not introduced in Romania ), all participants were diagnosed during the first 6 weeks of life, a total of ten being asymptomatic at the time. Dietary intake of Phe was individually adapted (based on Phe tolerance). Patients who followed recommended treatment displayed normal neuro-motor development (10 cases ). Late diagnosis of PKU or failure to follow suggested diet led to varying degrees of retardation. Higher incidence of PKU between 2013-2015 ( 10 cases) compared to 2010-2012 ( 5 cases) was observed.