ISSN:
1432-1076
Keywords:
Hyperphenylalaninaemia
;
Atypical phenylketonuria
;
Bioprerin
;
Neurotransmitter
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Systematic investigation of hyperphenylalaninaemic infants for tetrahydrobiopterin deficiency has recently led to the description of new variants of cofactor deficiency. In the present case, the initial observation was of hyperphenylalaninaemia with a significant increase in the neopterin to biopterin ratio in the urine. A tetrahydrobiopterin loading test resulted in a significant decrease of blood phenylalanine levels. Cerebrospinal fluid (CSF) biopterin and neurotransmitter metabolite levels were within the normal range. The in vivo clearance of phenylalanine remained altered despite a high dietary tolerance. At 9 months of age, the patient was clinically well, but minor neurological signs appeared when blood phenylalanine levels increased. These data were similar to those found in the so-called “peripheral form” of tetrahydrobiopterin deficiency. However, an unidentified pteridinelike compound had been found in the urine and CSF since the birth, suggesting the existence of an unknown block in the biosynthetic pathway of biopterin.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00442213
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