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Licensed Unlicensed Requires Authentication Published by De Gruyter May 29, 2019

The European Phenylketonuria Guidelines and the challenges on management practices in Portugal

  • Cátia Sousa , Manuela Ferreira Almeida , Catarina Sousa Barbosa , Esmeralda Martins , Patrícia Janeiro , Isabel Tavares de Almeida , Anita MacDonald and Júlio César Rocha ORCID logo EMAIL logo



Phenylketonuria (PKU) management practices differ between and within countries. In 2007, the Portuguese Society for Metabolic Disorders (SPDM) approved the Portuguese Consensus (PC) for the nutritional treatment of PKU. The recently published European PKU Guidelines (EPG, 2017) systematically reviewed recent evidence and aimed to harmonise treatment protocols in Europe. The objective of this study was to appraise the EPG acceptance and implementation in Portuguese treatment centres.


An electronic questionnaire was prepared and the link was sent to 135 SPDM members. It outlined the 10 EPG key recommendations and compared each statement with the consensus recommendations published by SPDM. Responses were recorded and descriptive analyses were performed.


Twenty-five professionals completed the questionnaire, and over half (56%) were nutritionists/dieticians. At least one questionnaire from each of the 10 national treatment centres was returned. In general, responders accepted most of the recommendations. However, only the recommendation about target phenylalanine (Phe) concentrations between 120 and 360 μmol/L for patients <12 years received 100% consensus with a further seven recommendations gaining over 70% consensus. Almost half of the professionals (48%, n = 12) required further discussion about the EPG-safe upper target blood Phe concentration (600 μmol/L) suggested for patients aged ≥12 years. Almost one third (32%, n = 8) failed to agree with the recommendation in the EPG-proposed classification of Phe hydroxylase (PAH) deficiency.


The EPG received overall good acceptance, but there was divided opinion about some recommendations which require further discussion before implementation by the Portuguese treatment centres.

Corresponding author: Júlio César Rocha, PhD, Centro de Genética Médica, Centro Hospitalar Universitário do Porto – CHUP, Porto, Portugal; Centro de Referência na área de Doenças Hereditárias do Metabolismo, Centro Hospitalar Universitário do Porto – CHUP, Porto, Portugal; Centro de Genética Médica, Doutor Jacinto de Magalhães, CHUP, EPE, Praça Pedro Nunes 88, 4099-028 Porto, Portugal; and Center for Health Technology and Services Research [CINTESIS], Porto, Portugal, Phone: +351 22 6087415, Fax: +351 22 6070300,


The authors thank the Portuguese Society of Metabolic Disorders for supporting this study.

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

  3. Employment or leadership: None declared.

  4. Honorarium: None declared.

  5. Competing interests: Manuela Ferreira Almeida received grants from Glutamine, Nutricia, Merck Serono, Biomarin, Orphan and Lifediet to attend congress and for education. Anita MacDonald received research funding and honoraria from Nutricia, Vitaflo International and Merck Serono. She is a member of the European Nutritionist Expert Panel [Biomarin], member of Sapropterin Advisory Board [Biomarin], member of the Advisory Board entitled ELEMENT [Danone-Nutricia], and member of an Advisory Board for Arla and Applied Pharma Research. Júlio César Rocha is a member of the European Nutritionist Expert Panel [Biomarin], member of an Advisory Board for Applied Pharma Research s.a. and Nutricia. He received speaker fees from APR, Merck Serono, Biomarin, Nutricia, Vitaflo and Cambrooke.


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Received: 2018-12-10
Accepted: 2019-04-01
Published Online: 2019-05-29
Published in Print: 2019-06-26

©2019 Walter de Gruyter GmbH, Berlin/Boston

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