Screening Tests for Newborns

Overview |

ROUTINE TESTS: Congenital Disorders

IF AT RISK: Infectious Diseases | Inherited (Genetic) Disorders

PKU

Inheritance of this disorder results in a build-up of phenylalanine (a protein component), leading to developmental delays, seizures, and severe mental retardation. This condition is not usually fatal.

Restricting phenylalanine in the diet (abundant in meats, fish, and eggs and a predominant component of the artificial sweetener aspartame) and monitoring serum levels have proven effective in treating this condition if initiated as soon as possible and certainly before 4 weeks of age. For the person with PKU, treatment must continue throughout life.

Every U.S. state tests newborns for this disorder. A PKU test is one of the 29 tests recommended for all newborns in the national standards announced in 2006. The standards, developed by the American College of Medical Genetics, were commissioned by the federal Health Resources and Services Administration.

Limitation of PKU test:
Collection of an insufficient amount of specimen will affect the test result. Specimens should be collected from newborns older than 24 hours and younger than 7 days. Screening prior to 24 hours of age may result in an inaccurate result.