A Case of Dihydropteridine Reductase Deficiency

• Main Authors: Furujo Mahoko, Ichiba Yozo, Sintaku Haruo, Asada Minoru
• Format: Article
• Language: English
• Published: De Gruyter 2000-11-01
• Series: Pteridines
• Subjects: tetrahydrobiopterin(bh4) loading test; dihydropteridine reductase (dhpr); hyperprolactinemia; neurotransmitter precursor; homovanillic acid (hva); 5-hydroxyindole acetic acid (5hiaa); 5- hydroxy tryptophan (5-htp); quinonoid dihydrobiopterin (qbh2)' phenylketonuria (pku)
• Online Access: https://doi.org/10.1515/pteridines.2000.11.4.126

Tetrahydrobiopterin (BH4) is the essential cofacter of phenylalanine (Phe), tyrosine (Tyr), and tryptophan (Trp) hydroxylases . BH4 deficiency, a rare but severe type of hyperphenylalaninemia, is characterized by progressive neurologic symptoms despite early detection and treatment with a Phe-restricted formula. An expensive dose of BH4 is needed to keep with the Phe, Tyr and Trp hydroxylation reaction. Severe BH4 deficiency is a naturally occurring model of cerebral catecholamine and serotonin shortage. Here we present a patient in which the hyperpheny lalaninelTIia could be reversed with BH4 therapy, but the concentrations of homo vanillic acid (HVA ) and 5- hydroxy indole acetic acid (5HIAA) in cerebrospinal fluid (CSF) remained low. Administration of the neurotransmitter precursors iL-DOPA/carbidopa and 5-hydroxytryptophan jappeared to be the most effective treatment and may prevent neurological damage if started early in life