Phenylalanine Free Infant Formula in the Dietary Management of Phenylketonuria: Accetability and Tolerance

Yılmaz Ö.

Annual Symposium of the Society for the SSIEM 2019: Study of Inborn Errors of Metabolism, Rotterdam, Netherlands, 3 - 06 September 2019, vol.1, pp.89

  • Publication Type: Conference Paper / Summary Text
  • Volume: 1
  • City: Rotterdam
  • Country: Netherlands
  • Page Numbers: pp.89


Background: Phenylketonuria (PKU) is a rare metabolic disorder treated from newborn screening. The choice of suit- able phenylalanine (Phe)-free infant formula is limited. In infancy, Phe-free infant formula is a key component of a low Phe diet although infant acceptance and tolerance is rarely reported. The aim of this study was to assess gastroin- testinal tolerance, efficacy and acceptance of a new Phe-free infant formula (PKU Start®, Vitaflo International) in a group of infants with PKU.

Methods: We conducted an open prospective, UK multi- centre, 31-day intervention study in 10 infants (median age 3.4 m) diagnosed with PKU by newborn screening. Data was collected at baseline and study end about medications, length, and weight; daily on feed volume, gastrointestinal intolerance and formula acceptability; and weekly blood Phe levels.

Results: The study formula was well accepted and tolerated by infants. Prior to study product commencement, common problems were: poor feeding (n = 4), reflux (n = 3), consti- pation (n = 3), colic (n = 3), and flatulence (n = 2). There was suggestion that straining with defecation and vomiting reduced on the new formula but numbers were too small to reach statistically significant conclusions. Median blood Phe control was acceptable both at baseline (174 mmol/L) and whilst on the study formula (203 mmol/L). Infants grew and gained weight satisfactorily during the study period.Discussion: The new Phe-free infant formula was well accepted by infants who had both appropriate weight gain and acceptable blood Phe control. It was associated with some minor/mild gastrointestinal intolerance. The availability of more than one commercial Phe-free infant formula mini- mizes any risk of supply issues, and provides a choice for infants previously limited to one specialised formula, and is an important consideration in vulnerable infants with PKU. Conflict of Interest declared.