Test Id : FFTEN
Tetrahydrobiopterin and Neopterin Profile (BH4, N)
Method Name
A short description of the method used to perform the test
HPLC/Electrochemistry/Fluorescence
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
FTEN
BH4, N
Tetrahydrobiopterin & Neopterin
Specimen Type
Describes the specimen type validated for testing
CSF
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Medical Neurogenetics collection kit (T657) required.
Each collection kit contains 5 microcentrifuge tubes.
COLLECTION PROTOCOL:
1) CSF should be collected from the first drop into the tubes in the numbered order. Fill each tube to the marked line with the required volumes
Tube 1: 0.5 mL
Tube 2: 1.0 mL
Tube 3: 1.0 mL (contains antioxidants necessary to protect the sample integrity)
Tube 4: 1.0 mL
Tube 5: 1.0 mL
- If sample's not blood contaminated, the tubes should be placed on dry ice at bedside
- If sample's are blood contaminated, the tubes should immediately be centrifuged (prior to freezing) and the clear CSF transferred to new similarly labeled tubes, then frozen
- Store samples at -80 until they can be shipped
2) Complete Medical Neurogenetics, LLC request form. Include test required, sample date and date of birth.
3) Label tubes with patient name and ID number, leaving the tube number viewable.
4) Place samples inside a specimen transport bag and the Medical Neurogenetics, LLC request form inside the pouch of the transport bag.
5) Ship samples frozen on dry ice.
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Specimens other than | CSF in special collection kit (T657) |
| Anticoagulants other than | NA |
| Hemolysis | NA |
| Lipemia | NA |
| Icteric | NA |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| CSF | Frozen | CSF KIT | |
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
CSF Neopterin/Tetrahydrobiopterin (NC03) is useful for diagnosis of certain disorders of neurotransmitter metabolism. This testing may also be used for assessment of Variants of Uncertain Significance (VUS) identified during genetic testing (e.g. Next Generation Sequencing or Capillary Sequencing Testing). CLINICAL Tetrahydrobiopterin (BH4) serves as a cofactor for the hydroxylation of phenylalanine and in the biosynthesis of biogenic amines. Deficiency of BH4 may occur as a result of mutations causing a reduction in one of the three biosynthetic enzymes, guanosine triphosphate cyclohydrolase, 6-pyruvoyl-tetrahydropterin synthase, sepiapterin reductase, or the two regenerating enzymes, pterin-4-carbinolamine dehydratase, and dihydropteridine reductase. Defects in BH4 metabolism can result in hyperphenylalaninemia and deficiency of the neurotransmitters dopamine and serotonin. Changes in CSF neopterin may also occur in deficiency of the BH4 synthesis pathway. Disorders of BH4 metabolism are characterized by a wide range of symptoms that may include developmental delay, mental disability, behavioral disturbances, dystonia, Parkinsonian symptoms, gait disturbances, speech delay, psychomotor retardation and ptosis.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Tetrahydrobiopterin/Neopterin Profile
| Age | BH4 | Neop |
| (years) | (nmol/L) | (nmol/L) |
| 0 – 0.2 | 40 – 105 | 7 – 65 |
| 0.2 – 0.5 | 23 – 98 | 7 – 65 |
| 0.5 – 2.0 | 18 – 58 | 7 – 65 |
| 2.0 – 5.0 | 18 – 50 | 7 – 65 |
| 5.0 – 10 | 9 – 40 | 7 – 40 |
| 10 – 15 | 9 – 32 | 8 – 33 |
| Adults | 10 – 30 | 8 - 28 |
Note: If test results are consistent with the clinical presentation, please call our laboratory to discuss the case and/or submit a second sample for confirmatory testing.
An important consideration for false positive for false negative results is the improper labeling of the patient sample.
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Friday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
This test was developed and its performance characteristics determined by Medical Neurogenetics, LCC. It has not been cleared or approved by the U.S. FDA.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
82542
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| FFTEN | Tetrahydrobiopterin/Neopterin | 80168-8 |
| Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
|---|---|---|
| Z2234 | Neopterin | 34146-1 |
| Z2235 | Tetrahydrobiopterin | 59247-7 |
| Z2236 | Interpretation | 80173-8 |