Comparison of an amino acid mixture and protein hydrolysates in treatment of infants with phenylketonuria.

This study compares three feeding regimens for infants with phenylketonuria diagnosed by neonatal screening. Group 1 (five children) received Minafen (Cow & Gate) until they weighed twice their birthweights; Aminogran (Allen & Hanbury) was then added to the feeds in increasing amounts and replaced Minafen at between 8 and 10 months of age. Group 2 (five children) received Aminogran from the neonatal period. Group 3 (five children) received Minafen until they weighed twice their birthweights; Cymogran (Allen & Hanbury) was then added in increasing amounts and replaced Minafen at between 8 and 10 months of age. In all three groups growth was normal and control of phenylalanine levels satisfactory. During the first few months of life the Aminogran regimen proved more complicated and caused more practical difficulties than the regimens starting with Minafen. Later in the first year, when mixed feeding was introduced, and particularly when the bottle was exchanged for the cup, Aminogran had advantages over Cymogran because of its low calorie content, small bulk, and less unpleasant taste. At this age feeding problems were fewer and easier to manage with Aminogran than with Cymogran. A method of using Aminogran in the management of such problems is described. For these reasons, the regimen fed group 1, in which Minafen is used initially and then replaced by Aminogran, is preferred to the other two.