Test Code RKUR Potassium, Random, Urine
Reporting Name
Potassium, Random, UUseful For
Determining the cause for hyper- or hypokalemia using a random urine specimen
Performing Laboratory

Specimen Type
UrineSpecimen Required
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Container/Tube: Plastic, 5-mL tube
Specimen Volume: 4 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Specimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 14 days | |
Frozen | 30 days | ||
Ambient | 7 days |
Reference Values
No established reference values
Random urine potassium may be interpreted in conjunction with serum potassium, using both values to calculate fractional excretion of potassium.
The calculation for fractional excretion (FE) of potassium (K) is
FE(K)= ([K(urine) X Creat(serum)]/[K(serum) X Creat(urine)]) X 100
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
84133
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
RKUR | Potassium, Random, U | 2828-2 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
RKUR | Potassium, Random, U | 2828-2 |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. |
Method Name
Potentiometric, Indirect Ion-Selective Electrode (ISE)
Day(s) Performed
Monday through Sunday