10 Symptoms of a Kidney Problem

Heidi Godman

You might think symptoms of kidney problems would be obvious. After all, the kidneys are among the most important organs in the body, carrying out crucial functions that enable us to live each day.

But symptoms of kidney problems can be subtle, and that's when they're most dangerous. "Kidney disease is one of the silent diseases that can lead to severe long-term disability or even death if left untreated. It's the forgotten pandemic," says Dr. Abdul Ali Abdellatif, adjunct assistant professor of medicine in Baylor College of Medicine's division of nephrology.

It's important to recognize signs that your kidneys could be inflamed, infected, damaged or at increased risk for serious problems down the road.

What Do the Kidneys Do?

The two bean-shaped kidneys are part of the urinary tract system. They are located under your ribs, on either side of the backbone.

The kidneys have a number of jobs. Among them, the kidneys:

-- Clean the blood. The kidneys filter about 200 quarts of blood each day, removing toxins, acid, chemicals and extra fluid. The waste (urine) is sent down the ureters to the bladder, where it's stored until it exits the body through the urethra.

-- Regulate blood pressure. They kidneys control fluid levels in the body, and they produce hormones that make blood vessels narrow.

-- Maintain bone health. The kidneys make the active form of vitamin D, and they balance calcium and phosphorus in the body, which make bones strong.

-- Regulate red blood cell production. The kidneys produce hormones that alert bones to produce red blood cells, which deliver oxygen throughout the body.

[See: 5 Ways to Reduce Your Risk of Developing Kidney Disease.]

10 Symptoms of Kidney Problems in Adults

The following signs can all be symptoms of kidney problems.

1. Swelling. A swollen face or swollen hands, feet or legs could be signs of severe kidney disease. "It could be related to the kidneys' inability to get rid of extra fluids or salt in the body, or maybe the kidney is leaking protein that makes the body swell up," Abdellatif says.

2. Sudden pain. You might develop upper back pain or flank pain that radiates to the front of your body. This can indicate that you have a urinary tract infection that has migrated up to the kidneys, which are now infected. Extreme pain is a sign of kidney stones -- pellets that result from excess minerals and salt inside the kidney.

3. Changes in urine appearance. Urine may appear brown or red, indicating that it contains blood. "When the kidney gets damaged by any insult, including kidney disease, kidney stones, cancer, cysts or inflammation, that makes the kidneys get weak and allows blood to leak," Abdellatif explains. Urine that appears frothy or foamy can indicate that the kidney is leaking protein.

4. Fatigue. Advanced kidney disease can keep the kidneys from producing erythropoietin, the hormone that regulates red blood cell production. That can lead to anemia, a lack of red blood cells, which can cause you to feel fatigued because your body isn't getting enough oxygen.

5. Sudden muscle twitching. "A buildup of toxins in the circulation can cause sudden muscle twitching," Abdellatif says. "This would be a sign of advanced kidney disease."

6. Confusion. Another symptom of advanced kidney disease, this can develop because of a buildup of toxins that affect the brain.

7. High blood pressure. Kidney disease is one of the most common causes of hypertension. "The kidneys regulate how much salt should stay in our circulation. If they're unable (to do that) and salt stays in the blood, it can increase blood pressure," Abdellatif says. "Or if the kidney has damage, it can activate production of hormones that lead to high blood pressure."

8. Diabetes. "Diabetes is the most common cause of kidney disease in this country," Abdellatif says. High levels of blood sugar can damage the kidneys, although it rarely causes obvious symptoms of kidney problems early on.

9. Gout. Excess uric acid causes swelling in the joints, especially the big toe, that's very painful. "Ninety percent of the time, a patient will have gout because of the kidney's inability to get rid of uric acid from the blood stream," Abdellatif notes.

10. Frequent urinary tract infections. Recurrent UTIs may be caused by kidney stones, among other triggers. UTIs increase the risk for kidney infection, which can damage the kidneys if untreated.

[SEE: Who Can Help Me With Kidney Problems?]

Symptoms of Kidney Problems in Children

Symptoms of kidney problems are often different in children. "Not just in the signs, but in how a child might experience and report them. You have young children who can't express themselves and might experience a symptom from the moment they're born but not know it's abnormal," says Dr. Jeffrey Saland, a pediatric nephrologist with Mount Sinai Health System.

For example, Saland says kids might not have any pain from kidney stones, which are often excruciatingly painful for adults. "At least half the kids I see with kidney stones report no pain at all, even if they have multiple kidney stones. I don't have a great explanation for that," Saland says.

Kidney problems in children include birth defects that cause blockages in the kidneys or kidney stones that can be caused by rare conditions such as primary hyperoxaluria type 1. In PH1, the liver makes too much of the substance oxalate, which can stick together and form numerous stones in the kidneys, leading to kidney disease.

How do you know if you have a child with symptoms of kidney problems? Saland says to look for signs that adults experience, such as:

-- Changes in urine appearance.

-- High blood pressure.

-- Swelling.

Other signs such as high fevers, reduced urine output, frequent urinary tract infections or kidney stones are particularly concerning in children. "If a child even has one kidney stone it needs to be checked out because there may be a life-changing diagnosis like PH1," Saland warns.

What You Should Do

If you have one or more symptoms of kidney problems, or if your child has one or more symptoms, talk to your primary care doctor or your child's pediatrician. If something needs to be investigated, you may be referred to a nephrologist.

An evaluation would include:

-- Physical exam.

-- Thorough medical history.

-- Blood test to check kidney function.

-- Urine test (urinalysis) to look for signs of kidney damage.

Your doctor may also order a kidney ultrasound or biopsy to get more information.

In some cases, treating a kidney-related problem, such as a urinary tract infection that ascended into the kidneys, could be a simple matter of taking an antibiotic. If it's a kidney stone, you may need to let it pass and then change your diet to limit foods with a lot of oxalate (such as spinach).

More serious conditions, such as advanced kidney disease, will also require a lifestyle change, along with regular doctor visits and more advanced treatments.

But don't let diagnosis possibilities keep you from seeking help. "If you're an adult with advanced kidney disease," Saland says, "it could be that your first (obvious) sign of disease is that it's advanced." In other words, don't ignore symptoms of kidney problems, no matter how subtle.

Heidi Godman reports on health for U.S. News, with a focus on middle and older age. Her work has appeared in dozens of publications, including the Harvard Health Letter (where she serves as executive editor), the Chicago Tribune, Baltimore Sun, Orlando Sentinel and Cleveland Clinic Heart Advisor.

Heidi spent more than 20 years as a TV news anchor and health reporter at ABC affiliate WWSB and more than five years as the host of a daily health talk radio show on WSRQ-FM. Heidi has interviewed surgeons in operating rooms, scientists in laboratories and patients in all phases of treatment. She's earned numerous awards for outstanding health reporting and was the first TV broadcaster in the nation to be named a journalism fellow of the American Academy of Neurology. Heidi graduated from West Virginia University with a degree in journalism.

Connect with Heidi on Linkedin or email her at health@heidigodman.com.