Sign in →

Test ID CRE2 Creatinine, Urine


Specimen Required


Only orderable as part of a profile. For more information see:

-ALBR / Albumin, Random, Urine

-RALB / Albumin, Random, Urine.

 

Supplies: Sarstedt 5 mL Aliquot Tube (T914)

Container/Tube: Plastic tube

Specimen Volume: 5 mL

Collection Instructions:

1. Collect a random urine specimen.

2. No preservative.


Secondary ID

614427

Useful For

Normalization of urinary analytes to account for the variation in urinary concentrations between individuals when using random urine collections

Method Name

Only orderable as part of a profile. For more information see:

ALBR / Albumin, Random, Urine

RALB / Albumin, Random, Urine.

 

Enzymatic Colorimetric Assay

Reporting Name

Creatinine

Specimen Type

Urine

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time
Urine Refrigerated (preferred) 30 days
  Ambient  30 days
  Frozen  30 days

Clinical Information

Creatinine is formed from the metabolism of creatine and phosphocreatine, both of which are principally found in muscle. Thus, the amount of creatinine produced is in large part dependent upon the individual's muscle mass and tends not to fluctuate much from day-to-day.

 

Creatinine is not protein-bound and is freely filtered by glomeruli. All of the filtered creatinine is excreted in the urine. Renal tubular secretion of creatinine also contributes to a small proportion of excreted creatinine. Although most excreted creatinine is derived from an individual's muscle, dietary protein intake, particularly of cooked meat, can contribute to urinary creatinine levels.

 

The renal clearance of creatinine provides an estimate of glomerular filtration rate (GFR). Since creatinine, for the most part, in the urine only comes from filtration, the concentration of creatinine reflects overall urinary concentration. Therefore, creatinine can be used to normalize other analytes in a random urine specimen.

Reference Values

Only orderable as part of a profile. For more information see:

ALBR / Albumin, Random, Urine

RALB / Albumin, Random, Urine.

 

Not applicable

Cautions

Intra-individual variability in creatinine excretion may be due to differences in muscle mass or amount of ingested meat.

 

Acute changes in glomerular filtration rate, before a steady state has developed, will alter the amount of urinary creatinine excreted.

Day(s) Performed

Monday through Sunday

Report Available

1 day

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

82570

NY State Approved

Yes