[Adult phenylketonuria].

Starting from 1975 phenylketonuria is part of the newborn screening program in Hungary. Since then a generation, treated with special diet and medical foods right after neonatal diagnosis has reached adulthood. Thanks to early treatment initiation, children with phenylketonuria are able to lead life to the full. Consequently, phenylketonuria is no longer considered a pediatric disease. Follow up of adult patients with phenylketonuria is performed in internal medicine centers specialized in metabolic diseases. The outcome of the lifelong special treatment, and the particularities of phenylketonuria in adulthood are yet to be determined. The aim of our review is to present recent findings in phenylketonuria focusing mainly on the adult care. After long time the first international guidelines appeared, new therapies were put in use, and these current developments are expected to be implemented in daily practice in the near future. New challenges must be met such as maternal phenylketonuria, long term effects of dietotherapy and the sequelae of untreated phenylketonuria in adulthood. Orv Hetil. 2017; 158(46): 1857-1863.