What does the Urine Creatinine test measure?

Why is Urine Creatinine measured?

Random urine creatinine is used almost exclusively to standardise spot urine measurements of albumin, protein, electrolytes, heavy metals, and hormones, converting absolute concentrations into creatinine-corrected ratios. The albumin-to-creatinine ratio is the first-line test for albuminuria in chronic kidney disease and diabetic kidney disease, and protein-to-creatinine ratios replace 24-hour urine collections in many settings. An isolated urine creatinine is rarely clinically meaningful, but values below 20 mg/dL raise concern for an excessively dilute or incorrectly collected specimen.

Reference ranges

Standard reference

Approximately 20–320 mg/dL in random specimens; highly variable with hydration and muscle mass.

Functional medicine optimal

There is no optimal clinical range; values are judged in the context of the analyte being normalised and the degree of urine concentration.

Units

mmol/L, mg/dL, g/L

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.