What is an albumin/creatinine ratio test?
An albumin/creatinine ratio (ACR) test checks for kidney disease by measuring the amount of albumin and creatinine in a urine sample.
- Albumin is a protein that is usually found in the blood. When the kidneys are working properly, albumin is typically not present in the urine in significant amounts because the glomeruli (the kidney’s filtration units) do not allow large molecules like albumin to pass through. However, if the kidneys are damaged, these filters can become leaky, allowing albumin to escape into the urine.
- Creatinine is a waste product that is produced during the normal breakdown of protein from food and muscle tissue. It is removed from the body through the kidneys and is expected to be found in the urine if the kidneys are healthy.
An ACR test measures the amount of albumin in urine relative to the amount of creatinine. Elevated amounts of albumin (protein) in the urine is called albuminuria or proteinuria, and is a sign of kidney damage. This test can be used by people living with chronic conditions that increase their risk for kidney damage, as well as anyone who would like to assess their risk of kidney disease.
What is albuminuria?
Also called proteinuria, albuminuria means that you have too much protein in your urine. A healthy kidney does not let protein pass from the blood to the urine. Protein in your urine is a sign that the kidneys are not filtering correctly and may be damaged.
Chronic kidney disease (CKD) is increasing in prevalence globally and is expected to become the fifth leading cause of death by 2040 (Kovedsky, 2022). Albuminuria can be an early sign of CKD and is one of the strongest risk factors for CKD that progresses to kidney failure with time.
How common is kidney disease?
Kidney disease has been referred to as a “silent epidemic”, as it has few symptoms in early stages, is not widely known, and an increasing number of people are at risk for it. It is estimated that 100 million adults in the EU currently live with CKD, with millions more at risk of developing CKD in the future. Many people with CKD are unaware they have the disease, particularly in early stages. This means they may not receive timely treatment that can prevent CKD from progressing to kidney failure. An albumin/creatinine ratio test is a simple way to check for early signs of CKD from home.
What does the Kidney Damage Test result mean?
A normal amount of albumin in your urine is less than 30 mg/g. Anything above 30 mg/g may mean you have kidney disease. Albuminuria can be short-term or long-term (chronic). Some of the most common causes of temporary (short-term) albuminuria include
- Dehydration
- High-intensity exercise
- Fever or infection
- Heart failure exacerbation
Some of the most common causes of chronic albuminuria include
- Diabetes (especially if your blood sugar is higher than your target range)
- Hypertension
- Heart disease and/or heart failure
- Glomerular disease (such as IgA nephropathy, lupus nephritis, focal segmental glomerulosclerosis (FSGS), or glomerulonephritis)
If you have an elevated level of albumin in your urine, contact your doctor for follow-up testing and treatment.
How soon will I receive my test results?
Once you have collected your sample and then mailed it to our laboratory, it generally takes a few working days before you receive the test result. As soon as your test sample arrives at the laboratory you will receive a notification by email. Once your test result is ready, you will receive a text message and an email from us with a link to your test result. We will therefore keep you well informed throughout the entire testing process!
What is the albumin/creatinine ratio?
The albumin/creatinine ratio (ACR) is a measurement that quantifies the amount of albumin in urine relative to the amount of creatinine. It’s expressed in milligrams of albumin per gram of creatinine (mg/g). This ratio is used to assess kidney function, specifically the kidney’s ability to filter albumin.
What is albumin?
Albumin is a protein found in the bloodstream. Healthy kidneys typically filter out waste products while retaining important substances like albumin. However, if kidneys are damaged, they may allow albumin to pass into the urine, leading to increased levels in the urine.
What is creatinine?
Creatinine is a waste product from the breakdown of creatine, a molecule important for muscle energy storage. Creatinine is routinely excreted in urine. Since its excretion rate is relatively stable in most individuals, it serves as a useful reference point for urine concentration. The ACR helps standardize the measurement of albumin in urine by taking into account the concentration of urine, which can be influenced by hydration status and other factors. Relating the albumin level to the creatinine level allows for a more consistent and reliable measure of kidney filtration function, regardless of urine concentration.
