RT Book, Section A1 Burgard, Peter A1 Luo, Xiaoping A1 Levy, Harvey L. A1 Hoffmann, Georg F. A2 Sarafoglou, Kyriakie A2 Hoffmann, Georg F. A2 Roth, Karl S. SR Print(0) ID 1140316516 T1 Phenylketonuria T2 Pediatric Endocrinology and Inborn Errors of Metabolism, 2e YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9780071773140 LK accesspediatrics.mhmedical.com/content.aspx?aid=1140316516 RD 2024/03/29 AB Classical phenylketonuria (PKU) is an autosomal recessive disorder of phenylalanine metabolism. It results in severe mental retardation and additional neurological problems when treatment does not begin within the first few weeks of life. However, when a very strict diet is begun early and carefully maintained, affected children can be expected to show normal development and experience a normal life span. The worldwide overall incidence is approximately 1:10,000 with a large national/ethnic variability (1:20,000 live births in South America, 1:4500 in Ireland, 1:2600 in Turkey, 1:11,000 in China, and 1:200,000 in Finland).1 In Europe, the estimated prevalence in the general population is 1:8500.2 Because of the severity of the disease if untreated and the excellent outcome when children are treated early and well, newborn screening for PKU has been instituted in many countries.