Porphobilinogen (PBG), Urine
Also known as: PBGQT
Use
Porphobilinogen (PBG) in urine is an essential first-line test for suspected acute porphyria in adults. It is used to evaluate an attack of acute porphyria, with results normalized to creatinine concentration to report as a ratio. Slight increases in urinary PBG are 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.
Special Instructions
Not provided.
Limitations
The test does not provide a definitive diagnosis of porphyria types but helps assess acute porphyria attacks. Results must be interpreted in the context of clinical symptoms and other lab findings. Factors such as deviations in collection time or volume can affect result interpretation, requiring ratios of analytes to a corresponding urine creatinine concentration for accuracy.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
Porphobilinogen
Analyte
LOINC Codes
- 35674-1 - Creat ?Tm Ur-mCnc
- 2162-6 - Creat 24h Ur-mRate
- 14882-5 - PBG 24h Ur-sRate
- 2811-8 - PBG Ur-sCnc
- 19153-6 - Specimen vol ?Tm Ur
- 30211-7 - Specimen collect Time Spec
- 34357-4 - PBG/Creat Ur-sRto
- 93479-4 - Observation Imp
Result Turnaround Time
1-5 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
2 mL
Minimum Volume
1.5 mL
Container
ARUP amber transport tubes
Collection Instructions
Collect random or 24-hour urine. Refrigerate 24-hour specimens during collection.
Storage Instructions
Frozen.
Causes for Rejection
Body fluids other than urine.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | 1 week |
| Frozen | 1 month |
Other tests from different labs that may be relevant