Urine Creatinine Concentration

Kidney Function marker

Urine Creatinine

Urine Creatinine Concentration

Category: Kidney Function
Unit: mmol/L

Creatinine concentration in urine. Used to calculate the albumin/creatinine ratio and assess specimen adequacy.

PED Notes

Urine creatinine is higher in muscular individuals due to greater creatinine production from muscle mass. This is expected and not a concern — unlike serum creatinine, higher urine creatinine reflects normal excretion. A very low urine creatinine may indicate a dilute specimen (over-hydration before collection).

When high

Understanding Urine Creatinine:

  • Primary use is as a denominator for the Albumin/Creatinine Ratio (ACR)
  • Higher values in muscular individuals are expected and normal

If Very High:

  • In muscular athletes, this is expected from high muscle mass and creatine turnover
  • Not a clinical concern — it actually makes the ACR calculation more reliable

Specimen Collection Tips:

  • Use first morning void for most concentrated and consistent sample
  • Avoid excessive water intake before collection (dilutes sample)
  • Avoid intense exercise 24-48h before collection
  • Do not collect during illness or fever

When low

Understanding Urine Creatinine:

  • Primary use is as a denominator for the Albumin/Creatinine Ratio (ACR)
  • Very low urine creatinine (<2.0 mmol/L) suggests dilute specimen — retest with first morning urine

If Very Low (dilute specimen):

  • Repeat test with first morning urine
  • Moderate fluid intake the evening before
  • An excessively dilute sample makes the ACR unreliable

Specimen Collection Tips:

  • Use first morning void for most concentrated and consistent sample
  • Avoid excessive water intake before collection (dilutes sample)
  • Avoid intense exercise 24-48h before collection
  • Do not collect during illness or fever

History Chart

Reading History

Frequently Asked Questions

Reference Ranges

Standard Range

Not available

Statistics