title: Maternal Phenylketonuria International Collaborative Study revisited: evaluation of maternal nutritional risk factors besides phenylalanine for fetal congenital heart defects.
abstract: Maternal phenylketonuria (MPKU) is known to affect fetal outcome, often being associated with microcephaly and congenital heart defects (CHD) if the maternal diet is not appropriately managed. We hypothesized that other nutrients aside from phenylalanine (Phe) may have significant effects on fetal outcome in MPKU pregnancies. The 416 pregnancies that resulted in live births reported in the Maternal PKU Collaborative Study (MPKUCS) were grouped according to whether or not the offspring were diagnosed with CHD. The groups were compared on first-trimester values of maternal data, including weight gain, plasma amino acids, protein and Phe intake, and red blood cell (RBC) folate. Patients were also grouped by first-trimester average blood Phe (≤910 μmol/L and >910 μmol/L) and then divided by total natural protein and medical food intake. The CHD group of 28 offspring had significantly higher blood Phe and lower proline, valine, methionine, isoleucine, leucine, lysine, arginine, and RBC folate. A significantly higher risk for CHD was found in the groups with lower natural protein and medical food intake, regardless of blood Phe levels. Insufficient natural protein and medical food product intake appears to be a risk factor for CHD independent of first-trimester plasma Phe levels. Low RBC folate and plasma methionine levels in the CHD group may suggest involvement of global DNA hypomethylation.
authors.affiliation: Genetics Division, Department of Pediatrics, LAC + USC Medical Center, Keck School of Medicine, University of Southern California, General Laboratory Building Room 1G-24, 1801 Marengo Street, Los Angeles, CA, 90033, USA, syano@usc.edu.
authors.forename: Shoji
authors.initials: S
authors.lastname: Yano
authors.forename: Kathryn
authors.initials: K
authors.lastname: Moseley
authors.forename: Teodoro
authors.initials: T
authors.lastname: Bottiglieri
authors.forename: Erland
authors.initials: E
authors.lastname: Arning
authors.forename: Colleen
authors.initials: C
authors.lastname: Azen
mesh_terms: D000596:Amino Acids / Q000097:blood; D001835:Body Weight; D004044:Dietary Proteins / Q000737:chemistry; D005260:Female; D005492:Folic Acid / Q000097:blood; D006330:Heart Defects, Congenital / Q000175:diagnosis* / Q000209:etiology*; D006801:Humans; D010649:Phenylalanine / Q000097:blood / Q000737:chemistry*; D017042:Phenylketonuria, Maternal / Q000503:physiopathology* / Q000628:therapy; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology*; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First; D012042:Registries; D012307:Risk Factors; D015430:Weight Gain
chemical_list: D000596:Amino Acids; D004044:Dietary Proteins; D010649:Phenylalanine; D005492:Folic Acid