Test Code PBGD_ Porphobilinogen Deaminase, Whole Blood
Performing Laboratory
Mayo Clinic Laboratories in RochesterReporting Name
PBG Deaminase, WBSpecimen Type
Whole bloodOrdering Guidance
This test is for diagnosis of acute intermittent porphyria. Porphobilinogen deaminase, also known as uroporphyrinogen I synthase, is commonly confused with uroporphyrinogen III synthase, the enzyme deficient in congenital erythropoietic porphyria (CEP). For CEP cases, order UPGC / Uroporphyrinogen III Synthase (Co-Synthase), Erythrocytes.
Necessary Information
1. Patient’s age is required
2. Include a list of medications the patient is currently taking.
Specimen Required
Patient Preparation: Patient must not consume any alcohol for 24 hours before specimen collection. This is essential as ethanol induces porphobilinogen deaminase activity, which may lead to a false-normal result.
Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA) or green top (lithium heparin)
Specimen Volume: 4 mL
Collection Instructions: Refrigerate specimen as soon as possible.
Reject Due To
Gross hemolysis | Reject |
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole blood | Refrigerated (preferred) | 8 days | |
Ambient | 7 days |
Specimen Minimum Volume
3 mL
Special Instructions
Day(s) Performed
Thursday
Specimen Retention Time
14 daysReport Available
2 to 8 daysReference Values
Reference ranges have not been established for patients who are younger than 16 years.
≥7.0 nmol/L/sec
6.0-6.9 nmol/L/sec (indeterminate)
<6.0 nmol/L/sec (diminished)
Useful For
Confirmation of a diagnosis of acute intermittent porphyria
Testing Algorithm
The following algorithms are available:
-Porphyria (Acute) Testing Algorithm
CPT Code Information
82657
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
PBGD_ | PBG Deaminase, WB | 12810-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
4022 | PBG Deaminase, WB | 12810-8 |
28400 | Interpretation | 59462-2 |
606470 | Reviewed By | 18771-6 |
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.