Porphyrins and Porphobilinogen (PBG), Urine
Also known as: PORUFPBGU
Use
The test evaluates patients with suspected porphyria presenting with neurologic/psychiatric, abdominal, and/or cutaneous symptoms. Urine porphobilinogen (PBG) is useful for evaluating neurologic and/or psychiatric symptoms to exclude acute porphyrias such as acute intermittent porphyria (AIP). It also helps assess cutaneous photosensitivity to exclude porphyria cutanea tarda (PCT).
Special Instructions
Not provided.
Limitations
Results are normalized to creatinine concentration and reported as a ratio of amounts (micromoles of porphyrin/moles of creatinine). Slight increases in urinary PBG can be associated with acute porphyrias other than acute intermittent porphyria (AIP) and may indicate a resolving or treated acute porphyria. Urinary PBG in excess of two times the upper reference limit is consistent with acute porphyria.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 35674-1 - Creat ?Tm Ur-mCnc
- 2162-6 - Creat 24h Ur-mRate
- 2811-8 - PBG Ur-sCnc
- 32043-2 - Uropor/Creat 24h Ur-sRto
- 38175-6 - Heptacarboxylate/Creat Ur-sRto
- 14882-5 - PBG 24h Ur-sRate
- 49292-6 - Porphyrin Fract 24h Ur-Imp
- 19153-6 - Specimen vol ?Tm Ur
- 30211-7 - Specimen collect Time Spec
- 45313-4 - Copro1/Creat Ur-sRto
- 45315-9 - Copro3/Creat Ur-sRto
- 34357-4 - PBG/Creat Ur-sRto
- 93479-4 - Observation Imp
Result Turnaround Time
2-5 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
8 mL
Minimum Volume
4 mL
Container
ARUP amber transport tube
Collection Instructions
Collect 24-hour or random urine. Refrigerate 24-hour specimens during collection. Protect from light and transfer aliquot to a transport tube.
Storage Instructions
Frozen.
Causes for Rejection
Body fluids other than urine.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | 4 days |
| Frozen | 1 month |
Other tests from different labs that may be relevant