Tags

Type your tag names separated by a space and hit enter

An international survey of patients with tetrahydrobiopterin deficiencies presenting with hyperphenylalaninaemia.
J Inherit Metab Dis. 2012 Nov; 35(6):963-73.JI

Abstract

OBJECTIVES

The present study summarizes clinical and biochemical findings, current treatment strategies and follow-up in patients with tetrahydrobiopterin (BH(4)) deficiencies.

METHODS

We analyzed the clinical, biochemical and treatment data of 626 patients with BH(4) deficiencies [355 with 6-pyruvoyl-tetrahydropterin synthase (PTPS), 217 with dihydropteridine reductase (DHPR), 31 with autosomal recessive GTP cyclohydrolase I (GTPCH), and 23 with pterin-4a-carbinolamine dehydratase (PCD) deficiencies] from the BIODEF Database. Patients with autosomal dominant GTPCH and SR deficiencies will not be discussed in detail.

RESULTS

Up to 57 % of neonates with BH(4) deficiencies are already clinically symptomatic. During infancy and childhood, the predominant symptoms are muscular hypotonia, mental retardation and age-dependent movement disorders, including dystonia. The laboratory diagnosis of BH(4) deficiency is based on a positive newborn screening (NBS) for phenylketonuria (PKU), characteristic profiles of urinary or dried blood spot pterins (biopterin, neopterin, and primapterin), and the measurement of DHPR activity in blood. Some patients with autosomal recessive GTPCH deficiency and all with sepiapterin reductase deficiency may be diagnosed late due to normal blood phenylalanine in NBS. L-dopa, 5-hydroxytryptophan, and BH(4) are supplemented in PTPS and GTPCH-deficient patients, whereas L-dopa, 5-hydroxytryptophan, folinic acid and diet are used in DHPR-deficient patients. Medication doses vary widely among patients, and our understanding of the effects of dopamine agonists and monoamine catabolism inhibitors are limited.

CONCLUSIONS

BH(4) deficiencies are a group of treatable pediatric neurotransmitter disorders that are characterized by motor dysfunction, mental retardation, impaired muscle tone, movement disorders and epileptic seizures. Although the outcomes of BH(4) deficiencies are highly variable, early diagnosis and treatment result in improved outcomes.

Authors+Show Affiliations

Division of Inborn Metabolic Diseases, University Childrens Hospital Heidelberg, Im Neuenheimer Feld 430, 69120, Heidelberg, Germany.No affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

22729819

Citation

Opladen, Thomas, et al. "An International Survey of Patients With Tetrahydrobiopterin Deficiencies Presenting With Hyperphenylalaninaemia." Journal of Inherited Metabolic Disease, vol. 35, no. 6, 2012, pp. 963-73.
Opladen T, Hoffmann GF, Blau N. An international survey of patients with tetrahydrobiopterin deficiencies presenting with hyperphenylalaninaemia. J Inherit Metab Dis. 2012;35(6):963-73.
Opladen, T., Hoffmann, G. F., & Blau, N. (2012). An international survey of patients with tetrahydrobiopterin deficiencies presenting with hyperphenylalaninaemia. Journal of Inherited Metabolic Disease, 35(6), 963-73. https://doi.org/10.1007/s10545-012-9506-x
Opladen T, Hoffmann GF, Blau N. An International Survey of Patients With Tetrahydrobiopterin Deficiencies Presenting With Hyperphenylalaninaemia. J Inherit Metab Dis. 2012;35(6):963-73. PubMed PMID: 22729819.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - An international survey of patients with tetrahydrobiopterin deficiencies presenting with hyperphenylalaninaemia. AU - Opladen,Thomas, AU - Hoffmann,Georg F, AU - Blau,Nenad, Y1 - 2012/06/23/ PY - 2012/03/11/received PY - 2012/05/28/accepted PY - 2012/05/12/revised PY - 2012/6/26/entrez PY - 2012/6/26/pubmed PY - 2013/4/6/medline SP - 963 EP - 73 JF - Journal of inherited metabolic disease JO - J Inherit Metab Dis VL - 35 IS - 6 N2 - OBJECTIVES: The present study summarizes clinical and biochemical findings, current treatment strategies and follow-up in patients with tetrahydrobiopterin (BH(4)) deficiencies. METHODS: We analyzed the clinical, biochemical and treatment data of 626 patients with BH(4) deficiencies [355 with 6-pyruvoyl-tetrahydropterin synthase (PTPS), 217 with dihydropteridine reductase (DHPR), 31 with autosomal recessive GTP cyclohydrolase I (GTPCH), and 23 with pterin-4a-carbinolamine dehydratase (PCD) deficiencies] from the BIODEF Database. Patients with autosomal dominant GTPCH and SR deficiencies will not be discussed in detail. RESULTS: Up to 57 % of neonates with BH(4) deficiencies are already clinically symptomatic. During infancy and childhood, the predominant symptoms are muscular hypotonia, mental retardation and age-dependent movement disorders, including dystonia. The laboratory diagnosis of BH(4) deficiency is based on a positive newborn screening (NBS) for phenylketonuria (PKU), characteristic profiles of urinary or dried blood spot pterins (biopterin, neopterin, and primapterin), and the measurement of DHPR activity in blood. Some patients with autosomal recessive GTPCH deficiency and all with sepiapterin reductase deficiency may be diagnosed late due to normal blood phenylalanine in NBS. L-dopa, 5-hydroxytryptophan, and BH(4) are supplemented in PTPS and GTPCH-deficient patients, whereas L-dopa, 5-hydroxytryptophan, folinic acid and diet are used in DHPR-deficient patients. Medication doses vary widely among patients, and our understanding of the effects of dopamine agonists and monoamine catabolism inhibitors are limited. CONCLUSIONS: BH(4) deficiencies are a group of treatable pediatric neurotransmitter disorders that are characterized by motor dysfunction, mental retardation, impaired muscle tone, movement disorders and epileptic seizures. Although the outcomes of BH(4) deficiencies are highly variable, early diagnosis and treatment result in improved outcomes. SN - 1573-2665 UR - https://wwww.unboundmedicine.com/medline/citation/22729819/An_international_survey_of_patients_with_tetrahydrobiopterin_deficiencies_presenting_with_hyperphenylalaninaemia_ L2 - https://doi.org/10.1007/s10545-012-9506-x DB - PRIME DP - Unbound Medicine ER -