Your urine test came back with a number for albumin, or a lab flag next to "microalbumin creatinine ratio," and your doctor wants to repeat it. This test is one of the earliest ways to spot kidney damage, often before blood tests change and usually before you feel anything. This guide explains what the microalbumin test measures, what the normal range is, why one high result is not a diagnosis, how the number fits with your eGFR, what lowers albumin in urine, and where kidney research stands.
Told you have protein in your urine?
Researchers are testing new medicines for adults with chronic kidney disease or protein in the urine who are not on dialysis. See if a study near you is a match.
What the microalbumin test measures
Albumin is a protein that normally stays in your blood. Healthy kidneys filter waste out of the blood but hold on to albumin, so only a trace reaches the urine. When the kidneys’ filters are damaged, more albumin leaks through.
The test measures that albumin and compares it with creatinine, a waste product that passes into urine at a fairly steady rate. Using a ratio corrects for how diluted or concentrated your urine happens to be, so a single sample can be used instead of collecting urine all day.
Lab reports use several names for the same test: microalbumin creatinine ratio, urine albumin to creatinine ratio (UACR), albumin creatinine ratio (ACR), or urine microalbumin. "Microalbumin" is an older word. Kidney specialists now prefer "albuminuria," because risk rises steadily with the amount of albumin rather than switching on at one cutoff.
Microalbumin creatinine ratio normal range
Results are usually reported in milligrams of albumin per gram of creatinine (mg/g). International kidney guidelines group them into three categories:
- Below 30 mg/g: Normal to mildly increased (A1) (older term: normal)
- 30 to 300 mg/g: Moderately increased (A2) (older term: microalbuminuria)
- Above 300 mg/g: Severely increased (A3) (older term: macroalbuminuria)
Some labs report results in mg/mmol, where the same cutoffs are about 3 and 30. A result in the moderately increased range is the "high microalbumin" most people search for. It often shows up in people with diabetes or high blood pressure, and it is the stage at which treatment can make the biggest difference.
Who should get a microalbumin test, and how often
Anyone with diabetes should have the test at least once a year, and the American Diabetes Association recommends starting at the diagnosis of type 2 diabetes. The test is also used for people with high blood pressure, heart disease, a family history of kidney disease, diabetes, or high blood pressure, people over 50, and people who smoke or live with obesity. If you are in one of these groups, ask your doctor how often you need it.
How the test is done
Most labs use a random urine sample collected at any time of day. Some ask for the first urine of the morning, often with a home kit. A 24-hour collection, where you save all your urine for a full day, is the most accurate and is usually used to follow up an abnormal single result. Before the test, you may be asked to avoid intense exercise and meat for a day, and to tell the lab if you are menstruating.
Why one high result is not a diagnosis
Albumin in urine can rise for a short time for reasons that have nothing to do with lasting kidney damage, including intense exercise, fever, inflammation or infection, some medicines, and menstruation. That is why an abnormal result is usually repeated two more times within three to six months.
If two of the three results are high, it points to kidney damage, and your doctor will look at your eGFR and other kidney tests too. Chronic kidney disease is diagnosed when signs of kidney damage last at least three months.
What a high microalbumin creatinine ratio means
A result that stays above 30 mg/g means the kidneys’ filters are leaking albumin. It is one of the earliest signs of kidney disease, especially in diabetes, where it is a key marker of diabetic kidney disease. The more albumin in the urine, the higher the risk of both kidney failure and heart disease, which is why doctors track the number over time.
Most people with a high result have no symptoms at all. You cannot feel albumin in your urine, which is exactly why the test exists.
How UACR fits with your eGFR
Doctors stage kidney disease with two numbers: eGFR, a blood test that estimates how well the kidneys filter, and UACR, which shows how much albumin is leaking. Two people with the same eGFR can face very different risks depending on their UACR. Our guide to stage 3 kidney disease explains how both numbers are read together. If your blood creatinine was also flagged, see what high creatinine means and how to read the BUN/creatinine ratio.
How to lower albumin in urine
Treatment aims to protect the kidneys, and the albumin level is one of the ways your doctor checks whether it is working. The main steps are:
- Blood pressure control. For most people with diabetes, guidelines aim for a blood pressure below 130/80.
- Blood sugar control, if you have diabetes.
- ACE inhibitors or ARBs. Medicines such as lisinopril or losartan lower blood pressure and reduce albumin leakage. Diabetes guidelines recommend them for people with high blood pressure and albumin in the urine.
- SGLT2 inhibitors. Farxiga was approved for chronic kidney disease in April 2021 and Jardiance in September 2023, for people with or without diabetes.
- Kerendia (finerenone), approved in July 2021 for chronic kidney disease linked to type 2 diabetes.
- Ozempic (semaglutide), approved in January 2025 to lower the risk of worsening kidney disease in adults with type 2 diabetes and chronic kidney disease.
- Not smoking, staying active, and keeping a healthy weight.
Do not start, stop, or change any of these medicines on your own. Your doctor will usually recheck your UACR after a change in treatment.
Our guide to CKD stages explains how treatment changes as kidney disease progresses.
When protein in the urine points to research
Many kidney studies choose participants by the amount of albumin in their urine, usually alongside an eGFR range, because albumin is a sign of ongoing damage that new medicines aim to slow. Studies are recruiting across the US for chronic kidney disease, including IgA nephropathy, focal segmental glomerulosclerosis (FSGS), and diabetic kidney disease.
Most of these studies add a new medicine on top of the treatment you already take rather than replacing it, and some compare it with a placebo. Nothing is decided until you have gone through informed consent, and participation is voluntary at every step. You can browse kidney disease clinical trials near you on AllClinicalTrials.com.
Common questions
What is a normal microalbumin creatinine ratio? Below 30 mg/g. Labs may word the range slightly differently, and your doctor reads the result alongside your eGFR.
Is a microalbumin result between 30 and 300 bad? It is called moderately increased. If it stays in that range on repeat tests, it is an early sign of kidney damage, and it is also the stage where treatment can lower it. Talk with your doctor about what is causing it.
Can drinking more water lower my microalbumin result? Not really. Because the test compares albumin with creatinine, it already adjusts for how diluted your urine is. Staying hydrated is fine, but it will not change a truly high result.
Can albumin in urine go back to normal? It can fall with treatment, especially with good blood pressure and blood sugar control and medicines such as ACE inhibitors, ARBs, and SGLT2 inhibitors. Whether it returns fully to normal depends on the cause and how long it has been present.
Does a high microalbumin mean I will need dialysis? Not necessarily. It means a higher risk, and treatment aims to slow kidney damage. Your doctor uses UACR and eGFR together to estimate your own risk.
Do kidney study participants get paid? Some studies offer compensation for time and travel, and study related care is typically provided at no cost to participants. Compensation varies by trial and is always described during the informed consent process before you agree to anything.