PBG and ALA, P
GTR Test Accession: Help GTR000613072.2
Last updated in GTR: 2024-04-25
Last annual review date for the lab: 2023-05-30 LinkOut
At a Glance
Diagnosis; Monitoring
Porphyria; Acute intermittent porphyria; Hereditary coproporphyria; ...
Porphobilinogen; aminolevulinic acid
Biochemical Genetics - Analyte: Liquid chromatography-tandem mass spectrometry (LC-MS/MS)
An equivalent option to urine for first-line test for evaluation …
Not provided
Establish or confirm diagnosis
Ordering Information
Offered by: Help
Test short name: Help
Specimen Source: Help
Who can order: Help
  • Genetic Counselor
  • Health Care Provider
  • Licensed Dentist
  • Licensed Physician
  • Nurse Practitioner
  • Physician Assistant
  • Public Health Mandate
  • Registered Nurse
Lab contact: Help
Gisele (Gessi) Bentz Pino, MS, CGC, Certified Genetic counselor, CGC, Genetic Counselor
Contact Policy: Help
Laboratory can only accept contact from health care providers. Patients/families are encouraged to discuss genetic testing options with their health care provider.
How to Order: Help
Order URL
Test development: Help
Test developed by laboratory (no manufacturer test name)
Informed consent required: Help
Based on applicable state law
Pre-test genetic counseling required: Help
Decline to answer
Post-test genetic counseling required: Help
Decline to answer
Recommended fields not provided:
Conditions Help
Total conditions: 4
Condition/Phenotype Identifier
Test Targets
Analytes Help
Total analytes: 2
Analyte Associated Condition
Total methods: 1
Method Category Help
Test method Help
Instrument *
Liquid chromatography-tandem mass spectrometry (LC-MS/MS)
* Instrument: Not provided
Clinical Information
Test purpose: Help
Diagnosis; Monitoring
Clinical utility: Help
Establish or confirm diagnosis
View citations (1)
  • Tortorelli S, Kloke K, Raymond K. Disorders of porphyrin metabolism. In: Dietzen DJ, Bennett MJ, Wong ECC, eds. Biochemical and Molecular Basis of Pediatric Disease. 4th ed. AACC Press; 2010:307-324

Target population: Help
An equivalent option to urine for first-line test for evaluation of a suspected acute porphyria. Monitoring patients undergoing treatment for an acute intermittent porphyria or other acute porphyria.
View citations (2)
Variant Interpretation:
What is the protocol for interpreting a variation as a VUS? Help

Will the lab re-contact the ordering physician if variant interpretation changes? Help
Not provided. N/A
Is research allowed on the sample after clinical testing is complete? Help
Recommended fields not provided:
Technical Information
Test Procedure: Help
In a microcentrifuge tube, internal standard and plasma are combined, centrifuged, and then subjected to solid phase extraction (SPE). The SPE eluate is evaporated and the residue is then reconstituted and subjected to liquid chromatography tandem mass spectrometry analysis.(Unpublished Mayo method)
Availability: Help
Tests performed
Entire test performed in-house
Analytical Validity: Help
Accuracy was assessed by method comparison and the analysis of proficiency testing specimens and was acceptable. Intra assay precision was performed at 3 levels: CV results ranged from 7% to 17% for ALA and 4% to 6% for PBG (N=20 each). Inter assay precision was performed at 3 levels: CV … View more
Assay limitations: Help
Additional testing must be performed to distinguish among the acute porphyrias. The specimen should be collected prior to treatment as therapy may decrease the amount of porphobilinogen (PBG) and aminolevulinic acid. Specimens should be protected from light and frozen immediately following collection. PBG is susceptible to degradation at high temperatures … View more
Proficiency testing (PT):
Is proficiency testing performed for this test? Help

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help

Description of PT method: Help
Formal PT program.

Description of internal test validation method: Help
This test was laboratory developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements.
Software used to interpret novel variations Help

Laboratory's policy on reporting novel variations Help
Recommended fields not provided:
Regulatory Approval
FDA Review: Help
Category: FDA exercises enforcement discretion
Additional Information

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