Biopterin is needed as cofactor for phenylalanine, tryptophan & tyrosine hydroxylases, and NO synthase. A deficiency in synthesis or recycling of biopterin leads to problems in the metabolic pathways of these substances. Indication for testing: patients with hyperphenylalaninaemia. Phenylalanine at the time of sampling must be > 200 umol/L in order to interpret results.
Tube
Dried Blood Spot
ID
Tests&Tubes0160
Additional Information
Required sample type is: Dried blood spot (Guthrie) card. NB Blood cannot be spotted from an anti-coagulated tube.
Turn Around
Turnaround time stated by Birmingham Children’s Hospital: 15 working days.
Send to
Blood Sciences LGI
(Test referred to: Birmingham Children’s Hospital).
Contact
For further details please contact Leeds Pathology customer services: [email protected].
Collection Con
Minimum Volume: NA. Dried blood spot (BSD) – NOT from anti-coagulated blood. Ideally collect when phenylalanine is increased.
2 x 10 mm spots for DHPR.
6 x 10 mm spots for biopterins (+ 1 extra if phenylalanine result is not provided).
Instructions to lab: store frozen prior to dispatch
Ref. Range Notes
Interpretation will be provided on report.