Diabetes
Urine albumin-to-creatinine ratio
The urine albumin-to-creatinine ratio (uACR) measures albumin in urine relative to creatinine, correcting a random spot sample for how dilute or concentrated the urine is. It is the preferred test for detecting and monitoring early kidney damage in people with diabetes.
Why it is measured
Persistently raised albuminuria is an early marker of diabetic kidney disease and an independent predictor of cardiovascular risk. uACR therefore underpins routine annual screening and treatment decisions in diabetes care.
| Typical range | Indicative adult categories: normal to mildly increased (A1) under 3 mg/mmol, roughly under 30 mg/g; moderately increased (A2) 3 to 30 mg/mmol, roughly 30 to 300 mg/g; severely increased (A3) above 30 mg/mmol, roughly above 300 mg/g. Cut-offs and reporting units vary by method and assay, and a single raised result should be confirmed on a repeat sample. |
|---|---|
| Sample | Random spot urine, ideally a first-void early-morning specimen to reduce day-to-day variability. No fasting is required, but collection during heavy exercise, fever, urinary tract infection or menstruation is best avoided. |
| Turnaround | Typically about 5 to 7 minutes per cartridge on benchtop POCT analysers. Smartphone-read home kits return a result within a few minutes. |
Point of care devices that report it
- Abbott Afinion 2 (Afinion ACR test cartridge)
- Siemens Healthineers DCA Vantage (DCA Microalbumin/Creatinine ACR urine test)
- Siemens Healthineers CLINITEK Status+ with CLINITEK Microalbumin reagent strips (semi-quantitative albumin-to-creatinine ratio)
- Healthy.io Minuteful Kidney (smartphone-read home uACR test)
Questions, answered
Why report the ratio instead of just the urine albumin level?
Dividing albumin by creatinine corrects for urine concentration, so a quick random spot sample gives a result that is comparable to a timed collection without the inconvenience of a 24-hour urine collection.
Should a single raised uACR be acted on immediately?
Guidelines generally advise confirming a raised result, because exercise, fever, urinary tract infection, menstrual contamination and recent high protein intake can transiently raise albuminuria. Two raised results out of three over roughly three months are commonly used to establish persistent albuminuria. This is general guidance, not advice for an individual.
Do point-of-care analysers agree with the central laboratory?
Published method comparisons show good correlation between devices such as the Afinion and DCA Vantage and laboratory assays. Absolute values and category cut-offs can differ slightly between methods, so where possible it is good practice to monitor a patient on the same method over time.