What It Is
A microalbumin-to-creatinine ratio urine test involves measuring the amount of a protein called albumin in the urine. The amount of urine albumin is compared with the quantity of a waste product in the urine called cretonne.
The body normally filters out creatinine in the urine at a steady rate, so comparing the ratio of urine albumin with creatinine in the same urine specimen helps determine if the body is excreting albumin at an increased rate. If this is occurring it may be the result of kidney disease.
In most healthy people, the kidneys prevent albumin and other proteins from entering the urine. However, if kidneys are damaged and start to allow proteins to pass from the blood into the urine, the first type of protein to appear in the urine is albumin. This is because albumin molecules are smaller than most other protein molecules.
The consistent presence of small amounts of albumin in the urine is called microalbuminuria and is associated with early-stage kidney disease. Once there are larger amounts of albumin in the urine it is called macroalbuminuria and it could indicate more severe kidney disease.
Why It's Done
The microalbumin-to-creatinine ratio test is most commonly used to screen for kidney problems in teens with diabetes. It also might be done on a more regular basis, like once a year, in teens with diabetes to help in early identification of kidney disease.
It also can be used to monitor kidney function in kids and teens already diagnosed with kidney disease or taking medications that can affect the kidneys. The test can also help detect kidney complications from hypertension and autoimmune diseases.
Your child might need to temporarily stop taking specific drugs that could interfere with test results. Be sure to review all your child's medications with your doctor.
Your child will be asked to urinate (pee) into a clean sample cup in the doctor's office or at home. Collecting the specimen should only take a few minutes. If your child isn't potty trained and can't urinate into a cup, a catheter (a narrow, soft tube) may need to be inserted into the bladder to obtain the urine specimen.
A urine collection bag with adhesive tape on one end might instead be used to collect a sample from an infant. If you're doing the collection at home, you'll clean your baby's genital area and then attach the bag around the urinary opening. Once the bag is in place, you'll secure it with the attached tape. You can put a diaper on your baby once you've attached the bag. Remove the collection bag after your baby has urinated into it, usually within an hour. Deliver this specimen to your lab.
Sometimes, a doctor will want to test urine collected over a period of time ranging from 4 to 24 hours. After each urination, you or your child will pour the specimen from the sample cup into a larger container. Be careful not to touch the inside of the container. During the testing period, all the urine should be collected, even if it is just a small amount.
For specimens collected at home, follow any storage and transportation instructions the lab gives you. At the lab, the technician will determine the quantity of albumin in the urine and compare it with the amount of creatinine in the urine.
What to Expect
Because the test involves normal urination, there shouldn't be any discomfort as long as your child can provide a urine specimen. It's important to keep the area around the urinary opening clean before the test.
Getting the Results
The results of the microalbumin-to-creatinine test will be available in 1-3 days. It's important to know that children sometimes pass albumin in their urine even though they have no kidney damage.
If the test shows abnormal results, further tests will be ordered to determine if there's an illness and, if so, help diagnose it. Talk to your doctor about the meaning of the specific test results.
No risks are associated with the urine microalbumin-to-creatinine ratio test. Infants may occasionally experience skin irritation from the adhesive tape on the collection bag. If a catheterized specimen is required it may cause temporary discomfort.
You can discuss any questions you have about this procedure with your doctor.
Helping Your Child
The urine microalbumin-to-creatinine ratio test is painless. Explaining in simple terms how the test will be conducted and why it's being done, can help ease any fear. Make sure your child understands that there should be no foreign matter, such as toilet paper or hair, in the sample.
If You Have Questions
If you have questions about the microalbumin-to-creatinine ratio test, speak with your doctor.
Reviewed by: Yamini Durani, MD
Date reviewed: March 2012
|National Institute of Diabetes and Digestive and Kidney Diseases This group conducts and supports research on many serious diseases affecting public health.|
|National Kidney Foundation (NKF) NKF seeks to prevent kidney and urinary tract diseases, improve the health and well-being of individuals and families affected by these diseases, and increase the availability of all organs for transplantation.|
|American Association of Kidney Patients (AAKP) The AAKP serves kidney patients and their families by helping them cope with the emotional, physical, and social impact of kidney failure.|
|American Academy of Pediatrics (AAP) The AAP is committed to the health and well-being of infants, adolescents, and young adults. The website offers news articles and tips on health for families.|
|Urine Test: Microscopic Urinalysis A microscopic urinalysis can help detect a urinary tract infection (UTI), kidney problems, diabetes, or a urinary tract injury.|
|Urine Test: Creatinine Low levels of creatinine in the urine may point to a kidney disease, certain muscular and neuromuscular disorders, or an obstruction of the urinary tract.|
|Urine Test: Protein The urine protein test is most commonly used to screen for kidney disease and also can help monitor kidney function.|
|Kidneys and Urinary Tract The bean-shaped kidneys, each about the size of a child's fist, perform several functions essential to health. Their most important role is to filter blood and produce urine.|
|When Your Child Has a Chronic Kidney Disease Parents of kids who have a chronic kidney disease often worry about what might happen next, how their child feels, and what treatments are likely to be involved. Find answers here.|
|Kidney Diseases in Childhood The kidneys play a critical role in health. When something goes wrong, it could indicate a kidney disease. What are kidney diseases, and how can they be treated?|
|X-Ray Exam: Abdomen An abdominal X-ray can help find the cause of many abdominal problems, such as pain, kidney stones, intestinal blockage, a hole in the intestine, or an abdominal mass such as a tumor.|
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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