Pterin

Diagnostic Use

Tetrahydrobiopterin is a cofactor for phenyalanine hydroxylase (and also tryptophan and tyrosine hydroxylases). Raised blood phenyalanine found through newborn screening can be due to either a cofactor or an enzyme deficiency. All new PKU patients need a urine pterin assay to determine which of the above applies as the treatment differs (supplied cofactor if this is deficient; phenyalanine reduced diet if the enzyme is deficient). In this case the test is funded by the Newborn Metabolic Screening Programme.

Department

Specialist Biochemistry

Delphic Registration Code

UPTE

Synonyms

Tetrahydrobiopterin

Turnaround Time

6 weeks

Test Code

5820

Specimen Type

• Urine

Specimen Requirements

Tube/Container Type:

Preferred

• Pottle

Paediatric Specimen Requirements

Tube/Container Type:

Preferred

• Pottle

Preferred Sample Volume (ml)

5.0

Additional Specimen Information

Collect urine in subdued light. Wrap container immediately in tin foil and freeze (-15 to -20C OK for a few days) within 15 minutes. DO NOT ALLOW TO THAW. STORE FOIL WRAPPED -60 to -80C if possible. Send in DRY ICE.

Aliquot Instructions

Sample Type

• Urine

Transport to Lab

Frozen

Additional Referral/Aliquot Information

Collect urine in subdued light. Wrap container immediately in tin foil and freeze (-15 to -20C OK for a few days) within 15 minutes. DO NOT ALLOW TO THAW. STORE FOIL WRAPPED -60 to -80C if possible. Send in DRY ICE.

MUST be requested on special request form. See link below.

Test Method

to be entered

Non-Funded Test Cost

$73.34 (Exclusive of GST)

Billing Code

5820

Referred to NSW Biochemical Genetics
MUST be requested on special request form. See link below

Resources

• Urinary Pterin Request Form
• BH4 loading test information

Contact Information

Enquiry Form