| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Porphobilinogen, Quantitative, Random Urine
MessagePROTECT FROM LIGHT
Test Code
PORPHQLRU
Quest Code
6329
CPT Codes
84110
Preferred Specimen
2 mL unpreserved urine collected in a plastic leak-proof container
Minimum Volume
1 mL
Other Acceptable Specimens
Random clean-catch urine collected with 0.5g sodium carbonate (Na2CO3) per 100 mL of sample
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.
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 Temperature
Refrigerated (cold packs)
Specimen Stability
Room temperature: Unacceptable
Refrigerated: 7 days
Frozen: 30 days
Refrigerated: 7 days
Frozen: 30 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Not protected from light
Methodology
Chromatography/Mass Spectrometry
FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Setup Schedule
Set up: Tues, Thurs, Sat; Report available: 4-7 days
Reference Range
| ≤17 Years | <0.36 mg/g creat |
| ≥18 Years | <0.22 mg/g creat |
Clinical Significance
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.
Performing Laboratory
| Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
| 33608 Ortega Highway |
| San Juan Capistrano, CA 92675-2042 |
Last Updated: November 17, 2021
