The presence of abnormally high blood levels of phenylalanine, which may or may not be associated with elevated tyrosine levels, in newborn infants (premature and full-term), associated with the heterozygous state of phenylketonuria, maternal phenylketonuria, or transient deficiency of phenylalanine hydroxylase or p-hydroxyphenylpyruvic acid oxidase.
- malignant h. 1. dHPR-deficient form; an inherited disorder in which there is an absence or deficiency of dihydropteridine reductase (DHPR); this results in impaired regeneration of tetrahydrobiopterin, causing an elevation in phenylalanine levels; 2. gTP-CH form; an inherited disorder in which there is a deficiency of guanosine triphosphate cyclohydrolase, an enzyme used in the biosynthesis of tetrahydrobiopterin; 3. 6-PTS form; an inherited disorder in which there is a deficiency of 6-pyruvoyl tetrahydropterin synthase, an enzyme that participates in the biosynthesis of tetrahydrobiopterin. SYN: nonclassical phenylketonuria.
- non-PKU h. a benign phenotype in which phenylalanine monooxygenase is deficient but is greater than 1% of normal levels.

* * *

hy·per·phe·nyl·al·a·nin·emia or chiefly Brit hy·per·phe·nyl·al·a·nin·ae·mia -.fen-əl-.al-ə-nə-'nē-mē-ə, -.fēn- n the presence of excess phenylalanine in the blood (as in phenylketonuria)
hy·per·phe·nyl·al·a·nin·emic or chiefly Brit hy·per·phe·nyl·al·a·nin·ae·mic -'nē-mik adj

* * *

hy·per·phen·yl·al·a·nin·emia (HPA) (hi″pər-fen″əl-al″ə-nĭ-neґme-ə) 1. any of several autosomal recessive defects in the hydroxylation of phenylalanine resulting in accumulation and excretion of dietary phenylalanine. Most commonly the defect is in the enzyme phenylalanine hydroxylase (PAH); the most severe manifestation of this is phenylketonuria (q.v.), but less severe defects in the enzyme cause non-PKU hyperphenylalaninemia or variant phenylketonuria (qq.v.). Less commonly, the defect is in one of various enzymes involved in synthesis or regeneration of the cofactor tetrahydrobiopterin; see tetrahydrobiopterin deficiency, under deficiency. 2. excess of phenylalanine in the blood.

Medical dictionary. 2011.

Look at other dictionaries:

  • non-PKU hyperphenylalaninemia — an autosomal recessive condition caused by mutation in the PAH (locus: 12q24.1), which encodes phenylalanine hydroxylase; the resulting enzyme defect does not abolish enzyme activity; enough activity remains to keep plasma phenylalanine… …   Medical dictionary

  • PTS (gene) — 6 pyruvoyltetrahydropterin synthase, also known as PTS, is a human gene.cite web | title = Entrez Gene: PTS 6 pyruvoyltetrahydropterin synthase| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene Cmd=ShowDetailView TermToSearch=5805|… …   Wikipedia

  • PCBD1 — Pterin 4 alpha carbinolamine dehydratase/dimerization cofactor of hepatocyte nuclear factor 1 alpha PDB rendering based on 1dch …   Wikipedia

  • Phenylketonuria — PKU redirects here. For other uses, see PKU (disambiguation). Phenylketonuria Classification and external resources ICD 10 E70.0 ICD 9 …   Wikipedia

  • List of diseases (H) — A list of diseases in the English wikipedia.DiseasesTOC HaHag Ham* Hageman factor deficiency * Hagemoser Weinstein Bresnick syndrome * Hailey Hailey disease * Hair defect with photosensitivity and mental retardation * Hairy cell leukemia * Hairy… …   Wikipedia

  • Guthrie test — The Guthrie test, also known as the Guthrie bacterial inhibition assay, is a medical test performed on newborn infants to detect phenylketonuria, an inborn error of amino acid metabolism. The test has been widely used throughout North America and …   Wikipedia

  • phenylketonuria — phenylketonuric, adj. /fen l kee toh noor ee euh, nyoor , feen /, n. Pathol. an inherited disease due to faulty metabolism of phenylalanine, characterized by phenylketones in the urine and usually first noted by signs of mental retardation in… …   Universalium

  • phenylketonuria — Autosomal recessively inherited inborn error of metabolism of phenylalanine characterized by deficiency of 1) phenylalanine hydroxylase [MIM*261600] caused by mutation in the phenylalanine hydroxylase gene ( …   Medical dictionary

  • Phenylalanine — Phe redirects here. For other uses, see Phe (disambiguation). Phenylalanine …   Wikipedia

  • Список наследственных заболеваний — Список генетических заболеваний Основные статьи: наследственные заболевания, Наследственные болезни обмена веществ, Ферментопатия. В большинстве случаев приведен также код, указывающий на тип мутации и связанные с ней хромосомы. См. также система …   Википедия

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.