A core function of the kidneys is to clean your blood by expelling waste products and excess fluid as urine. So if you’ve noticed a change in your urine — such as color, cloudiness or unusual smell — it could be a sign that your kidney health is at risk.

Patrick Cunningham, MD, a nephrologist at the University of Chicago Medicine, is part of a team devoted to treating patients with glomerular disease (a type of kidney disease). UChicago Medicine offers a Nephrology Clinic at the Duchossois Center for Advanced Medicine in Hyde Park and a monthly satellite clinic at our River East location.

Cunningham explained how changes in urine can be potential indicators of kidney problems.

What do the kidneys do?

Kidneys are designed to filter out “bad” substances and only hold onto those that are essential for good health.

“Every day, we eat and drink different things, so it’s the kidneys' job to keep all kinds of chemicals in our bloodstream in perfect balance,” Cunningham said. “When your kidneys aren't working, they’re not able to do this as well.”

When that process is thrown off balance, it can show up in your urine.

What should my urine look like?

The look of your urine may vary, depending on what you eat and how much fluid you’ve consumed.

“If you’re drinking a lot of fluid, it might be clear,” Cunningham said. “If you get up in the morning after you haven’t been drinking fluid overnight, it’s naturally going to look darker — and that's normal.”

Staying hydrated is important for your overall health. For healthy adults, the average suggested daily water intake is about 15.5 cups for men and 11.5 cups for women, per federal guidelines.

How should my urine smell?

It’s common for your urine to have some smell, Cunningham said, and it doesn’t necessarily mean that anything is wrong if your urine has a strong odor.

“But if you notice something that's just very unusual from how it smells ordinarily, that might be a sign of urine infection,” he said.

Urine infections, otherwise known as urinary tract infections or UTIs, are caused by bacteria infecting the urinary tract.

What if my urine is cloudy, foamy, pink or reddish?

Cloudiness could also indicate a possible urine infection.

“While a little foaminess is normal, if it looks like the foam on the head of a beer, that could be a sign of excess protein in the urine,” Cunningham said. “A pink or red color could indicate various kidney diseases or conditions that affect other parts of your urinary tract, such as your bladder.”

Patients who have pink or red urine may assume they have an infection, but the culprit might be something else like autoimmune diseases (such as lupus), which should warrant a trip to your doctor immediately.

What are other symptoms of kidney disease?

Aside from changes in urine, other signs of kidney disease include a buildup of fluid in your legs or abdomen. Sometimes, autoimmune kidney diseases are also associated with a new rash or strange joint pains.

“Kidney disease can also cause things like difficulty breathing or blood pressure that’s suddenly much harder to control,” Cunningham said. Call your doctor immediately if you experience any of these issues.

What is glomerular disease?

The glomeruli, tiny structures that clean blood, are microscopic filter units located inside the kidneys. Each kidney has about 1 million glomeruli.

Damaged glomeruli reduce your kidneys’ ability to properly filter waste, meaning that abnormal amounts of protein and sometimes blood to leak into your urine, causing it to be pinkish, reddish, foamy or even brown in color.

“This damaged filtration system can be caused by diabetes or certain autoimmune diseases that attack many different organs inside the body,” Cunningham said. “It can also be genetic.”

How do I get treated for glomerular disease?

Treatment options depend on the cause, and diagnostic tests may be required.

“Sometimes it requires a biopsy of the kidney, which is not a surgery, but a medical procedure where we take a few little tiny pieces of kidney and examine it under a microscope,” Cunningham said.

Some patients might need immunosuppressive therapy. If their glomerular disease is caused by an autoimmune disease, they can receive medicine to reduce the overactivity of their immune system. In other cases, a patient may improve the course of their kidney disease with dedicated efforts and/or medicines to improve blood pressure.