PHENYLALANINE & TYROSINE PLASMA
General Information
HLAB/HOL Code: PHTYP
UPHSM LIS Test #: 023704
Schedule:
Testing Time: 2-4 Days
Testing Lab: Mayo Labs
UPHSM LIS Test #: 023704
Schedule:
Testing Time: 2-4 Days
Testing Lab: Mayo Labs
Specimen Info
Only 1 specimen type required, unless otherwise specified
Volume: 0.5 mL
Temperature: Frozen
Tube Type: Plasma
Collection Info:
Patient Preparation: Fasting (4 hours or more for infants)
Collection Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA)
Submission Container/Tube: Plastic vial
NECESSARY INFORMATION
1. Patient's age is required.
2. Include family history, clinical condition (asymptomatic or acute episode), diet, and drug therapy information.
Temperature: Frozen
Tube Type: Plasma
Collection Info:
Patient Preparation: Fasting (4 hours or more for infants)
Collection Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA)
Submission Container/Tube: Plastic vial
NECESSARY INFORMATION
1. Patient's age is required.
2. Include family history, clinical condition (asymptomatic or acute episode), diet, and drug therapy information.
Specimen Acceptability
REJECT DUE TO:
Gross hemolysis: OK
Gross lipemia: OK
Gross icterus: OK
Gross hemolysis: OK
Gross lipemia: OK
Gross icterus: OK
Methods
Monitoring effectiveness of dietary therapy in patients with hyperphenylalaninemia
Clinical Utilities
Defects in phenylalanine hydroxylase (PAH) cause the majority of cases of hyperphenylalaninemia (HPA); however, approximately 2% of infants with HPA have impaired synthesis or recycling of tetrahydrobiopterin (BH4).
Phenylketonuria: Evaluation of patients with hyperphenylalaninemia or monitoring effectiveness of dietary therapy. This test is not sufficient follow-up for abnormal newborn screening results, because other causes of hyperphenylalaninemia (eg, BH4 deficiency) cannot be excluded by this test alone.
Tyrosinemia, type I: For medical management.
Phenylketonuria: Evaluation of patients with hyperphenylalaninemia or monitoring effectiveness of dietary therapy. This test is not sufficient follow-up for abnormal newborn screening results, because other causes of hyperphenylalaninemia (eg, BH4 deficiency) cannot be excluded by this test alone.
Tyrosinemia, type I: For medical management.
CPT Codes
84030-Phenylalanine
84510-Tyrosine
84510-Tyrosine
* The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding
is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.
Reference Range
PHENYLALANINE
Premature: 98-213 nmol/mL
0-31 days: 38-137 nmol/mL
1-24 months: 31-75 nmol/mL
2-18 years: 26-91 nmol/mL
> or =19 years: 35-85 nmol/mL
Conversion Formulas:
Result in mg/dL x 60.6=result in nmol/mL
Result in nmol/mL x 0.0165=result in mg/dL
TYROSINE
Premature: 147-420 nmol/mL
0-31 days: 55-147 nmol/mL
1-24 months: 22-108 nmol/mL
2-18 years: 24-115 nmol/mL
> or =19 years: 34-112 nmol/mL
Conversion Formulas:
Result in mg/dL x 55.6=result in nmol/mL
Result in nmol/mL x 0.0181=result in mg/dL
See Inborn Errors of Amino Acid Metabolism in Special Instructions.
Premature: 98-213 nmol/mL
0-31 days: 38-137 nmol/mL
1-24 months: 31-75 nmol/mL
2-18 years: 26-91 nmol/mL
> or =19 years: 35-85 nmol/mL
Conversion Formulas:
Result in mg/dL x 60.6=result in nmol/mL
Result in nmol/mL x 0.0165=result in mg/dL
TYROSINE
Premature: 147-420 nmol/mL
0-31 days: 55-147 nmol/mL
1-24 months: 22-108 nmol/mL
2-18 years: 24-115 nmol/mL
> or =19 years: 34-112 nmol/mL
Conversion Formulas:
Result in mg/dL x 55.6=result in nmol/mL
Result in nmol/mL x 0.0181=result in mg/dL
See Inborn Errors of Amino Acid Metabolism in Special Instructions.
Component Info
Name: PHENYLALANINE
Method: IEC
CPT Code: 84030
Ref Range: 35-85
Comp Units: nmol/mL
Method: IEC
CPT Code: 84030
Ref Range: 35-85
Comp Units: nmol/mL
Name: TYROSINE
Method: IEC
CPT Code: 84510
Ref Range: 34-112
Comp Units: nmol/mL
Method: IEC
CPT Code: 84510
Ref Range: 34-112
Comp Units: nmol/mL
