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HelpOrder Code PBALP Porphobilinogen and Aminolevulinic Acid, Plasma
Shipping Instructions
Ship specimens refrigerated or frozen and in amber vial to protect from light.
Necessary Information
Include a list of medications the patient is currently taking.
Specimen Required
Patient Preparation: Patient must not consume any alcohol for at least 24 hours prior to specimen collection.
Supplies: Amber Frosted Tube, 5mL (T915)
Collection Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Green top (lithium heparin), lavender top (EDTA), yellow top (ACD A or B)
Submission Container/Tube: Amber vial
Specimen Volume: 1 mL
Collection Instructions:
1. It is recommended that specimen collection occur during the acute phase. Porphobilinogen and aminolevulinic acid may be normal when the patient is not exhibiting symptoms.
2. Centrifuge and aliquot plasma into plastic vial.
Useful For
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
Genetics Test Information
Plasma porphobilinogen and aminolevulinic acid (ALA) are elevated during the symptomatic phase of the acute porphyrias: acute intermittent porphyria (AIP), hereditary coproporphyria, and variegate porphyria.
An isolated elevation of ALA may be due to the very rare ALA dehydratase deficiency porphyria (ADP) or more commonly, a secondary inhibition of ALA dehydratase.
This test can be used as part of the diagnostic assessment and monitoring of patients with AIP and other acute porphyrias.
If ordered for diagnostic purposes, results are most informative when the specimen is obtained while the patient is having symptoms.
Additional testing must be performed to distinguish among the acute porphyrias.
Testing Algorithm
For more information see:
-The Heme Biosynthetic Pathway
Special Instructions
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
PBG and ALA, PSpecimen Type
PlasmaSpecimen Minimum Volume
0.3 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Plasma | Frozen (preferred) | 21 days | LIGHT PROTECTED |
| Refrigerated | 7 days | LIGHT PROTECTED |
Reject Due To
| Gross hemolysis | OK |
| Gross lipemia | OK |
| Gross icterus | OK |
Reference Values
Porphobilinogen: ≤0.5 nmol/mL
Aminolevulinic Acid: ≤0.5 nmol/mL
Method Description
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)
Day(s) Performed
Wednesday
Performing Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
82542
82135
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.