Test Code OSM24 Osmolality, 24 Hour, Urine
Necessary Information
24-Hour volume (in milliliters) is required.
Specimen Required
Supplies:
-Diazolidinyl Urea (Germall), 5.0 mL (T822)
-Urine Tubes, 10 mL (T068)
Container/Tube: 24-hour graduated urine container with no metal cap or glued insert
Specimen Volume: 10 mL
Collection Instructions:
1. Collect urine for 24 hours
2. Add 5 mL of diazolidinyl urea as preservative at start of collection or refrigerate specimen during and after collection.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.
Useful For
Assessing the concentrating and diluting ability of the kidney using a 24-hour urine collection
Reporting Name
Osmolality, 24 HR, USpecimen Type
UrineSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Urine | Refrigerated (preferred) | 14 days |
Frozen | 14 days | |
Ambient | 72 hours |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
0-11 months: 50-750 mOsm/kg
≥12 months: 150-1,150 mOsm/kg
Day(s) Performed
Monday through Sunday
Report Available
Same day/1 daySpecimen Retention Time
7 daysPerforming Laboratory

CPT Code Information
83935
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
OSM24 | Osmolality, 24 HR, U | 2694-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
UOS24 | Osmolality, 24 HR, U | 2694-8 |
TM02 | Collection Duration (h) | 13362-9 |
VL02 | Volume (mL) | 3167-4 |