title: Monitoring of biochemical status in children with Duarte galactosemia: utility of galactose, galactitol, galactonate, and galactose 1-phosphate.
abstract: BACKGROUND
  Duarte galactosemia (DG) is frequently detected in newborn-screening programs. DG patients do not manifest the symptoms of classic galactosemia, but whether they require dietary galactose restriction is controversial. We sought to assess the relationships of selected galactose metabolites (plasma galactose, plasma galactitol, erythrocyte (RBC) galactitol, RBC galactonate, and urine galactitol and galactonate) to RBC galactose 1-phosphate (Gal-1-P), dietary galactose intake, and neurodevelopmental/clinical outcomes in DG children.
  
  
  METHODS
  We studied 30 children 1-6 years of age who had DG galactosemia and were on a regular diet. All participants underwent a physical and ophthalmologic examination and a neurodevelopmental assessment. RBC galactitol, RBC galactonate, RBC Gal-1-P, plasma galactose, plasma galactonate, and urine galactitol and galactonate concentrations were measured.
  
  
  RESULTS
  RBC galactitol and galactonate concentrations were about 2 and 6 times higher, respectively, than control values. Plasma galactose and galactitol concentrations were also about twice the control values. The mean values for RBC Gal-1-P and urine galactitol were within the reference interval. We found a relationship between plasma and urine galactitol concentrations but no relationship between RBC galactose metabolites and urine galactitol. There was a significant relationship between galactose intake and RBC galactose metabolites, especially RBC galactitol (P < 0.0005) and RBC galactonate (P < 0.0005). Galactose intake was not related to the urine galactitol, plasma galactose, or plasma galactitol concentration. RBC galactitol, RBC galactonate, plasma galactose, plasma galactitol, and urine galactonate concentrations showed no relationship with clinical or developmental outcomes.
  
  
  CONCLUSIONS
  DG children on a regular diet have RBC Gal-1-P concentrations within the reference interval but increased concentrations of other galactose metabolites, including RBC galactitol and RBC galactonate. These increased concentrations correlate with galactose intake and neither cause any developmental or clinical pathology during early childhood nor oblige a lactose-restricted diet.
authors.affiliation: Department of Pediatrics, Section of Biochemical Genetics, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. Ficicioglu@email.chop.edu
authors.forename: Can
authors.initials: C
authors.lastname: Ficicioglu
authors.forename: Christie
authors.initials: C
authors.lastname: Hussa
authors.forename: Paul R
authors.initials: PR
authors.lastname: Gallagher
authors.forename: Nina
authors.initials: N
authors.lastname: Thomas
authors.forename: Claire
authors.initials: C
authors.lastname: Yager
mesh_terms: D002648:Child; D002675:Child, Preschool; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D004376:Galactitol / Q000032:analysis* / Q000097:blood / Q000652:urine; D005690:Galactose / Q000008:administration & dosage / Q000032:analysis* / Q000097:blood / Q000652:urine; D005693:Galactosemias / Q000097:blood* / Q000503:physiopathology / Q000652:urine*; D005695:Galactosephosphates / Q000032:analysis* / Q000097:blood / Q000652:urine; D006801:Humans; D007223:Infant; D008297:Male; D008991:Monitoring, Physiologic; D012016:Reference Values; D013400:Sugar Acids / Q000032:analysis* / Q000097:blood / Q000652:urine
chemical_list: D004040:Dietary Carbohydrates; D005695:Galactosephosphates; D013400:Sugar Acids; D004376:Galactitol; C012991:galactonic acid; C029973:galactose-1-phosphate; D005690:Galactose