A case of two sisters births from mother with phenylketonuria lacking mental retardation

Abstract

= Abstract = In this untreated classic phenylketonuria (PKU case mental retardation is severe; however there have been individuals- like the mother of this case- who have escaped mental retardation and all the other potential sequelae of phenylketonuria despite having high blood phenylalanine levels and very poor dietary control. It appears that they have nearly normal brain phenylalanine levels despite high blood phenylalanine (Phe levels. A number of studies have now demonstrated considerable variability in blood vs. brain phenylalanine levels in phenylketonuria patients. Outcome of phenylketonuria appears to be related to brain phenylalanine levels. We report a case of undiagnosed maternal phenylketonuria syndrome. A female infant had low birth weight (2400 g with microcephaly. We examined her family an dd iscovered that her mother was an undiag- nosed phenylketonuria patient with a borderline intelligence quotient ( IQ. The infant's sistersix years oldwas diagnosed with phenylketonuria at the age of four years was mentally retarded and had received an operation for cleft lip and palate. the sister had also had a low birth weight (2300 g. Her sister and mother were compound heterozygotes (mother: R243Q/Y325X; sister: Y325X/P407S. The infant and father were heterozygous carriers (baby: R243Q/-; father: P407S/-. (Korean J Pediatr 2008;51:546-550