Porphobilinogen, Quantitative, Random Urine
Test Code
Clinical Significance
Porphobilinogen, Quantitative, Random Urine - Urinary Porphobilinogen is the first step in the diagnosis of acute porphyrias such as acute intermittent porphyria (AIP). AIP is an autosomal dominant disorder characterized by deficiency of porphobilinogen deaminase. An acute attack usually includes gatrointestinal disturbance and neuropsychiatric disorders.
Test Details
Methodology
Reference Range(s)
| ≤17 Years | <0.36 mg/g creat |
| ≥18 Years | <0.22 mg/g creat |
Alternative Name(s)
Preferred Specimen(s)
2 mL urine (no preservative) collected in a plastic leak-proof container - protect from light
Alternative Specimen(s)
Random clean catch urine collected with 0.5g sodium carbonate (Na2CO3) per 100 mL of sample
Minimum Volume
1 mL
Collection Instructions
Urine should be refrigerated and protected from light.
Whenever possible, the specimen should be collected during an acute episode because porphobilinogen (PBG) may decrease rapidly upon remission. PBG may also degrade when samples are exposed to UV light for extended periods, or are transported at ambient temperature. If an amber collection jug/urine cup is not available, the sample must be protected from light by completely wrapping the container in aluminum foil. PBG is most stable at pH 6-7, but all samples may be sent with or without preservative. All results should be interpreted in the context of clinical findings, relevant history, and other laboratory data.
Transport Container
Transport tube
Transport Temperature
Refrigerated (cold packs)
Specimen Stability
- Room temperature: Unacceptable
- Refrigerated: 7 days
- Frozen: 30 days
Reject Criteria
Not protected from light
Setup Schedule
Whenever possible, the specimen should be collected during an acute episode because porphobilinogen (PBG) may decrease rapidly upon remission. PBG may also degrade when samples are exposed to UV light for extended periods, or are transported at ambient temperature. If an amber collection jug/urine cup is not available, the sample must be protected from light by completely wrapping the container in aluminum foil. PBG is most stable at pH 6-7, but all samples may be sent with or without preservative. All results should be interpreted in the context of clinical findings, relevant history, and other laboratory data.
Refrigerated: 7 days
Frozen: 30 days