title: The use of prealbumin concentration as a biomarker of nutritional status in treated phenylketonuric patients.
abstract: OBJECTIVE
  The neurological sequelae resulting from untreated phenylketonuria are diminished by the success of early introduced and continued dietary treatment. Nowadays, nutritional status is gaining importance in the follow-up of these patients. The aim of this work was to study the relevance of prealbumin concentration as biomarker of protein nutritional status of phenylketonuric patients.
  
  
  METHODS
  We collected data from 69 phenylketonuric patients on food intake, blood prealbumin and blood phenylalanine concentrations. Protein insufficiency was defined as prealbumin z-scores below the 5th percentile of reference population. Additionally, we considered a prealbumin concentration of 20 mg/dl as a threshold level.
  
  
  RESULTS
  Nine patients (13%) showed signs of protein insufficiency. When the threshold of 20 mg/dl for prealbumin was used, we found 38 patients (55%) with low prealbumin concentrations.
  
  
  CONCLUSIONS
  A significant group presented signs of protein insufficiency either using prealbumin z-scores or prealbumin concentration threshold, especially in milder forms of the disease. The results of this seem to confirm the already described threshold level for prealbumin concentration, suggesting that its measurement may be important for nutritional status evaluation, preventing protein insufficiency in milder forms of phenylketonuria.
authors.affiliation: Centro de Genética Médica Jacinto de Magalhães, INSA, Porto, Portugal. julio.rocha @ insa.min-saude.pt
authors.forename: Júlio César
authors.initials: JC
authors.lastname: Rocha
authors.forename: Manuela Ferreira
authors.initials: MF
authors.lastname: Almeida
authors.forename: Carla
authors.initials: C
authors.lastname: Carmona
authors.forename: Maria Luís
authors.initials: ML
authors.lastname: Cardoso
authors.forename: Nuno
authors.initials: N
authors.lastname: Borges
authors.forename: Isabel
authors.initials: I
authors.lastname: Soares
authors.forename: Graça
authors.initials: G
authors.lastname: Salcedo
authors.forename: Margarida Reis
authors.initials: MR
authors.lastname: Lima
authors.forename: Isabel
authors.initials: I
authors.lastname: Azevedo
authors.forename: Francjan J
authors.initials: FJ
authors.lastname: van Spronsen
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000378:metabolism; D015415:Biomarkers; D002648:Child; D002675:Child, Preschool; D004040:Dietary Carbohydrates / Q000494:pharmacology; D004041:Dietary Fats / Q000494:pharmacology; D004044:Dietary Proteins / Q000494:pharmacology; D002149:Energy Intake / Q000502:physiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009752:Nutritional Status / Q000502:physiology*; D010649:Phenylalanine / Q000097:blood; D010661:Phenylketonurias / Q000097:blood* / Q000178:diet therapy; D011228:Prealbumin / Q000378:metabolism*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D011228:Prealbumin; D010649:Phenylalanine