Order Code RBR Retinol-Binding Protein, Random, Urine
Specimen Required
Container/Tube: Plastic, 5-mL tube
Specimen Volume: 5 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Useful For
Assessing renal tubular injury or dysfunction using random urine collections
Screening for other tubular abnormalities
Detecting chronic asymptomatic renal tubular dysfunction.(2)
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
CRETR | Creatinine, Random, U | Yes, (Order RCTUR) | Yes |
RBPR | Retinol-Binding Protein, Random, U | No | Yes |
Method Name
CRETR: Enzymatic Colorimetric Assay
RBPR: Immunonephelometry
Reporting Name
Retinol-Binding Protein, Random, USpecimen Type
UrineSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 7 days | |
Frozen | 7 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
≥18 years: <190 mcg/g creatinine
Reference values have not been established for patients that are less than 18 years.
Method Description
Creatinine:
The enzymatic method is based on the determination of sarcosine from creatinine with the aid of creatininase, creatinase, and sarcosine oxidase. The liberated hydrogen peroxide is measured via a modified Trinder reaction using a colorimetric indicator. Optimization of the buffer system and the colorimetric indicator enables the creatinine concentration to be quantified both precisely and specifically.(Package insert: Creatinine plus ver 2. Roche Diagnostics; V16.0 02/2022)
Retinol-Binding Protein:
In an immunochemical reaction, urinary retinol-binding protein forms immune complexes with anti-retinol-binding protein-specific antibodies coated onto polystyrene latex particles. The resulting latex bead-antigen-antibody complexes have enhanced light-scattering ability, which is detected with a nephelometer when a beam of light is passed through the sample. The intensity of the scattered light is proportional to the concentration of retinol-binding protein in the sample. The result is evaluated by comparison with a standard of known retinol-binding protein concentration.(Package insert: Human Urine Retinol Binding Protein Nephelometric Kit for use on the Siemens BNII. The Binding Site Group Ltd; V27 11/2012)
Day(s) Performed
Monday, Wednesday, Friday
Performing Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
83883-Retinol -Binding Protein, Random, U
82570-Creatinine, Random, U
Forms
If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.