Understanding Medical Tests for Kidney Disease
Jake Newby
| 3 min read
You typically don’t know something is wrong with your kidneys until they are in seriously bad shape. According to the National Kidney Foundation, 37 million American adults live with chronic kidney disease (CKD) and about 90% of them don’t even know they have it. This is one of the many reasons kidney disease testing is so crucial.
CKD is a condition that can lead to kidney damage so severe, that they no longer filter blood properly. The damage usually progresses slowly, so this disease often develops without symptoms. Or, it causes you to feel nonspecific symptoms, like nausea, fatigue, and dry skin, for example. These nonspecific symptoms can be symptoms associated with other health conditions.
The most common cause of kidney disease is type 1 and type 2 diabetes. High blood pressure, a family history of kidney disease, heart disease, obesity and smoking/tobacco use are other common causes and risk factors. If you fall into any of these buckets, it’s especially important to be prudent about scheduling a kidney test.
What are the types of kidney disease tests?
There are two simple tests used to diagnose chronic kidney disease. These two tests are very important to determine if you may have kidney disease. An eGFR less than 60 and/or a uACR greater than 30 for three months or more may be a sign of CKD.
The blood test is called the estimated glomerular filtration rate (eGFR). The urine test called the urine albumin-creatinine ratio (uACR).
Urine albumin-creatinine ratio (uACR): This urine test measures two substances in your urine and compares them with each other:
- Albumin: This protein is found in the blood and helps repair tissue, build muscle and fight infection, but it should either not be found, or a very small amount should be found in the urine. One of the earliest signs of kidney disease is when albumin leaks into your urine; this is called albuminuria.
- Creatinine: A waste product that comes from normal muscle tissue breakdown.
A uACR test lets doctors know how much albumin passed into your urine. A urine albumin test result of 30 or above may indicate kidney disease. As noted by the Centers for Disease Control and Prevention (CDC), if you do have kidney disease, the amount of albumin in your urine helps your doctor know which treatment is best for you.
Estimated glomerular filtration rate (eGFR): An eGFR is an estimate of how well your kidneys are working. Serum creatinine level, age, and sex are used to calculate your estimated GFR number. The numbered result varies based on age and sex. As CKD progresses, your number decreases.
Additional tests that check for kidney problems
Your doctor may also want to monitor your blood pressure or recommend other tests, like a urine dipstick, imaging or a biopsy to check for any kidney problems.
Dipstick urine test: Often completed as part of an overall urinalysis work, urine dipstick tests are sometimes done as a quick way to detect if there is any blood, sugar or possible signs of infection. A dipstick is a chemically treated paper that, when placed in a urine sample, changes colors to indicate if levels are normal or not.
Kidney ultrasound: Imaging from a kidney ultrasound allows your provider to determine the size of your kidneys and see how well blood is flowing to your kidneys or if there is any blockage or narrowing in the blood vessels.
Kidney biopsy: A kidney biopsy nets results by inserting a thin needle through the skin to remove a small piece of kidney tissue that is examined under a microscope for signs of damage or disease.
Read on:
- The Importance of Diverse Organ Donors
- Risk of Colorectal Cancer is Higher in Patients with Chronic Kidney Disease
- How Hot Weather Affects the Kidneys
Photo credit: Getty Images
