6-pyruvoyl-tetrahydropterin synthase deficiency with mild hyperphenylalaninemia.
Severe 6-pyruvoyl-tetrahydrobiopterin synthase deficiency is a tetrahydrobiopterin deficiency disorder that presents in infancy with developmental delay, seizures, and abnormal movements associated with hyperphenylalaninemia usually detectable by neonatal phenylketonuria screening programs. We describe an 8-year-old girl with delay, seizures, and dystonia with mild hyperphenylalaninemia detected in late childhood. The diagnosis of 6-pyruvoyl-tetrahydrobiopterin synthase deficiency was made by analysis of pterins in urine, pterins and neurotransmitters in cerebrospinal fluid, and enzyme assay. The patient improved clinically taking oral tetrahydrobiopterin, levodopa/carbidopa, and 5-hydroxytryptophan. This treatable condition may not always be detected by routine population screening for hyperphenylalaninemia.
Department of Medical Genetics, University of British Columbia, Children's and Women's Health Centre of British Columbia, Vancouver, Canada. mdemos@cw.bc.ca
Michelle K
MK
Demos
Paula J
PJ
Waters
Hilary D
HD
Vallance
Yolanda
Y
Lillquist
Nawal
N
Makhseed
Keith
K
Hyland
Nenad
N
Blau
Mary B
MB
Connolly
D006916:5-Hydroxytryptophan / Q000627:therapeutic use; D001708:Biopterins / Q000031:analogs & derivatives / Q000627:therapeutic use; D002230:Carbidopa / Q000627:therapeutic use; D002547:Cerebral Palsy / Q000175:diagnosis; D002648:Child; D002658:Developmental Disabilities / Q000209:etiology; D003951:Diagnostic Errors; D015259:Dopamine Agents / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D009069:Movement Disorders / Q000209:etiology; D010649:Phenylalanine / Q000097:blood; D010661:Phenylketonurias / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy; D019761:Phosphorus-Oxygen Lyases / Q000172:deficiency*; D012640:Seizures / Q000209:etiology
D015259:Dopamine Agents; D001708:Biopterins; D007980:Levodopa; D010649:Phenylalanine; D006916:5-Hydroxytryptophan; D019761:Phosphorus-Oxygen Lyases; C043497:6-pyruvoyltetrahydropterin synthase; C003402:sapropterin; D002230:Carbidopa