Are you looking for a tool to determine the level of albuminuria in you or your patient? Use this albumin creatinine ratio calculator to ease the task. The tool quickly computes the ACR (albumin-to-creatinine ratio) and interprets the results.

Below, you'll find some useful information on what is microalbumin, urine microalbumin creatinine ratio use, the classification of the CKD stages, and more!

This tool mostly concentrates on chronic kidney disease. To find the cause of acute kidney injury, go to our FEUrea or FENa calculators.

Urine albumin creatinine ratio definition

Albumin-to-creatinine ratio serves as a detector of elevated protein levels in the urine (albuminuria), the first test to estimate kidney function. To perform these calculations, the lab needs just one sample of your urine. A 24-hour collection, as required for protein-creatinine ratio, is not necessary.

How to take a urine sample?

The best quality sample is from the first urination in the morning, after a proper washing of the genitals. The sample should be taken from middle part of the micturition and needs to be collected into a box then quickly delivered to the lab. 🧪

We calculate ACR by dividing urine microalbumin concentration in milligrams by the creatinine concentration in grams. You can find the interpretation of the results in the paragraphs below.

Albumin in urine - what does that mean?

Albumin in the urine, also known as albuminuria, along with a low GFR (glomerular filtration rate) and a high BUN (blood urea nitrogen) are signs that the kidneys are not functioning well. Albumin is a small protein typically present in the blood. It helps maintains the proper osmotic pressure and transports medications, hormones, etc throughout the body. In a healthy individual, no albumin should pass through the kidney barrier. If it does, albumin appears in the urine, and so it's a sign of kidney disease.

The presence of albumin in urine is called albuminuria, or sometimes proteinuria. Measurement of urine albumin is an important tool for diagnosing kidney disease and monitoring kidney disease progression. 🔬People at risk of kidney disease and increased ACR are those with:

They should all check their ACR regularly.

CKD stages - what is normal albumin creatinine ratio?

CKD, also known as Chronic Kidney Disease, is one of the main conditions leading to albuminuria. CKD is a process that slowly progresses throughout the years, decreasing the function of kidneys to a point where transplantation or dialysis is needed. 🥼 The best way to classify CKD is by GFR (glomerular filtration rate). In our case, the CKD stages can be also classified by the level of albuminuria.

Category ACR (mg/g) Terms
A1 <30 Normal to mildly increased
A2 30-300 Moderately increased
A3 >300 Severely increased

What is albumin creatinine ratio? Step-by-step ACR calculator

To use this ACR calculator, you need to have the albumin and creatinine concentration levels found in the urine. Albumin's unit is most probably mg/dL, whereas you might get mg/dL or mmol/L for creatinine.

The formula for ACR is:

ACR = Albumin / Creatinine

and the unit for ACR is mg/g.

Albumin creatinine ratio calculator in practice

Let's work on this load of theory in practice. Annie is a 63-year-old who has had blood tests every year as a means of prophylaxis. 🩸Those tests included a urine test to check for early signs of a complication related to her diabetes. Her GP (general practitioner) found some basic parameters, like glucose, white blood cells, and finally, albumin and creatinine.

This year though there was some worry with the latter two levels. The physician quickly calculated the ACR using this albumin creatinine ratio calculator.

  1. Albumin in urine: 8 mg/dL
  2. Creatinine: 110 mg/dL = 0.11 g/dL

ACR = Albumin/Creatinine

ACR = 8/0.11 = 72.7 mg/g

The table in the paragraph above shows that a result between 30 and 300 mg/g means the level of albuminuria is moderately increased, and the patient places in category A2 of CKD stages.

Dominika Miszewska, PhD candidate