History

Although PKU undoubtedly has been around for thousands of years, a child was not given dietetic treatment in Denmark until 1959.

In 1962, visiting nurses started testing the urine in the nappies of baby infants to identify signs of PKU. Unfortunately, the first tests resulted in a high number of false negatives meaning the diagnosis was frequently delayed. A nationwide blood sample to test for PKU was not introduced until 1974. The Guthrie test was used for many years. This is a blood sample taken from the heel of the infant. In 2002, tandem mass spectrometry was introduced, which is a much more sensitive and precise method.