Home
HelpTest ID UPGD Uroporphyrinogen Decarboxylase (UPG D), Whole Blood
Useful For
Preferred test for the confirmation of a diagnosis of porphyria cutanea tarda type II and hepatoerythropoietic porphyria
Genetics Test Information
Uroporphyrinogen decarboxylase (UPGD) is deficient in cases of type II porphyria cutanea tarda (PCT). Enzyme analysis is uninformative in sporadic PCT cases.
Due to longer specimen stability, this is the preferred test for analysis of UPGD enzyme.
Special Instructions
Method Name
High-Performance Liquid Chromatography (HPLC)/Incubation of Lysed Erythrocytes
Reporting Name
UPG Decarboxylase, WBSpecimen Type
Whole bloodAdvisory Information
Porphyria cutanea tarda (PCT) type I, the most common form of PCT, exhibits normal RBC enzyme activity. The preferred test for diagnosis of type I is PQNU / Porphyrins, Quantitative, 24 Hour, Urine or PQNRU / Porphyrins, Quantitative, Random, Urine.
Necessary Information
Include a list of medications the patient is currently taking.
Specimen Required
All porphyrin tests on whole blood can be performed on 1 draw tube.
Patient Preparation: Patient should abstain from alcohol for 24 hours
Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA) or light, green top (lithium heparin)
Specimen Volume: Full tube
Collection Instructions: Immediately place specimen on wet ice.
Specimen Minimum Volume
3 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole blood | Refrigerated | 7 days |
Reference Values
>1.0 Relative Units (normal)
0.80-0.99 Relative Units (indeterminate)
<0.80 Relative Units (porphyria cutanea tarda or hepatoerythropoietic porphyria)
Day(s) and Time(s) Performed
Tuesday; 8 a.m.
Performing Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
82657
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| UPGD | UPG Decarboxylase, WB | 49596-0 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 8599 | UPG Decarboxylase, WB | 49596-0 |
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.Testing Algorithm
The following algorithms are available in Special Instructions:
-Porphyria (Acute) Testing Algorithm
-Porphyria (Cutaneous) Testing Algorithm
Forms
2. If not ordering electronically, complete, print, and send an Inborn Errors of Metabolism Test Request (T798) with the specimen.