Tetrahydrobiopterin therapy for phenylketonuria in infants and young children.
OBJECTIVE
To describe patient selection, treatment administration, response evaluation, and side effect management associated with sapropterin therapy in infants and children aged <4 years.


METHODS
Six case reports are presented from 4 US metabolic clinics treating phenylketonuria with sapropterin in patients aged 7 months to 4 years. Outcomes included blood phenylalanine (Phe) levels before and during treatment. For 3 of 6 cases, diet records were used to monitor changes in dietary Phe.


RESULTS
Severity of phenylketonuria ranged from mild to severe (classic). Treatment with sapropterin was safe and generally well tolerated. Blood Phe levels were reduced, or maximum dietary Phe tolerance was increased in patients with blood Phe that was well controlled by diet.


CONCLUSIONS
Given the increasing evidence that maintaining blood Phe levels below 360 μmol/L is important for the normal development of neurocognitive and behavioral function, sapropterin can be combined with a Phe-restricted diet to control blood Phe levels in young patients responsive to sapropterin therapy.
Burton
Barbara K
BK
Department of Pediatrics, Northwestern University Feinberg School of Medicine and PKU Clinic, Children's Memorial Hospital, Chicago, IL 60614-3363, USA. bburton@childrensmemorial.org
Adams
Darius J
DJ
Grange
Dorothy K
DK
Malone
John I
JI
Jurecki
Elaina
E
Bausell
Heather
H
Marra
Kayt D
KD
Sprietsma
Laurie
L
Swan
Kathleen T
KT
D001708:Biopterins / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D018579:Patient Selection; D010649:Phenylalanine / Q000097:blood; D010661:Phenylketonurias / Q000188:drug therapy*; D016896:Treatment Outcome
D001708:Biopterins; D010649:Phenylalanine; C003402:sapropterin