Your kidneys continuously filter waste and extra fluid from the blood and help maintain the body's fluid, electrolyte and mineral balance. They also play important roles in blood pressure regulation and red blood cell production.
Kidney problems can have many causes, including diabetes, high blood pressure, kidney stones, urinary obstruction, infections and other medical conditions. Because some kidney diseases remain silent for a long time, routine medical evaluation can be important for people who have known risk factors.
Early Signs of Kidney Problems
The symptoms of kidney disease can vary depending on the cause and how much kidney function is affected. Importantly, early kidney disease may not cause noticeable symptoms at all.
Changes in Urination
Changes in how often you urinate, urine appearance, foaming or discomfort during urination may need evaluation.
Swelling
Swelling around the ankles, feet, legs or other areas may occur when the body retains excess fluid.
Persistent Tiredness
Ongoing fatigue or weakness can occur with advanced kidney problems, although it has many possible causes.
High Blood Pressure
High blood pressure can contribute to kidney damage and can also occur as a consequence of kidney disease.
Many of these symptoms can have causes unrelated to the kidneys. If symptoms are persistent, severe or unusual for you, speak with a healthcare professional.
Changes in Urine You Should Notice
Changes in urine can sometimes provide useful clues about urinary or kidney health. However, urine appearance and frequency can also change because of hydration, food, medicines, infections and other conditions.
Pink, red or brown urine may indicate blood and should be medically evaluated, especially if it is unexplained.
Persistent excessive foam can sometimes be associated with protein in the urine and deserves evaluation.
Noticeable changes in frequency or amount of urine can have several causes and may need assessment.
Burning or pain during urination is often related to urinary conditions such as infection, stones or other problems.
Swelling and Fluid Retention
Healthy kidneys help remove extra fluid from the body. When kidney function is significantly affected, fluid can build up and contribute to swelling.
Feet and Ankles
Swelling around the feet and ankles may be noticed after standing or throughout the day.
Legs
Fluid retention can sometimes cause swelling in the lower legs.
Around the Eyes
Puffiness around the eyes can have many causes and should be assessed in context.
Sudden Weight Changes
Unexpected rapid weight gain can sometimes reflect fluid retention and warrants medical assessment when unexplained.
Fatigue, Weakness and Other Possible Symptoms
As kidney disease becomes more advanced, some people may experience symptoms such as tiredness, weakness, difficulty concentrating, nausea, poor appetite or itching. These symptoms are not specific to kidney disease and should not be used as a diagnosis.
Persistent Fatigue
Ongoing tiredness that does not improve with adequate rest can have many causes and may require medical evaluation.
Difficulty Concentrating
Some people with significant kidney dysfunction may experience problems with concentration or mental clarity.
Nausea or Poor Appetite
Nausea and appetite changes can occur in advanced kidney disease but have many other possible explanations.
Itching or Dry Skin
Persistent itching can occur with advanced kidney disease and should be assessed if unexplained.
Sleep Problems
Sleep difficulties can occur in people with kidney disease, although they may also have many unrelated causes.
No Symptoms at All
Early kidney disease can have no noticeable symptoms. Testing can be more reliable than waiting for symptoms.
Who Is at Higher Risk of Kidney Problems?
Some people are more likely to develop kidney disease. Knowing your risk factors can help you and your doctor decide whether regular kidney-health testing is appropriate.
Diabetes
Diabetes is an important risk factor for chronic kidney disease.
High Blood Pressure
Long-term high blood pressure can damage blood vessels in the kidneys.
Family History
A family history of kidney disease may increase the importance of appropriate screening and medical advice.
Previous Kidney Problems
Kidney stones, urinary obstruction and certain previous kidney conditions can affect kidney health.
Remember: Having a risk factor does not mean you definitely have kidney disease. Your doctor can determine whether kidney function and urine testing are appropriate for you.
Tests That Can Check Kidney Health
Because early kidney disease may not cause symptoms, blood and urine tests can be useful when kidney disease is suspected or when someone has important risk factors.
Blood Creatinine Test
Blood creatinine is commonly used to help assess kidney filtration.
Estimated GFR
eGFR uses blood-test information and other factors to estimate kidney filtration function.
Urine Albumin Testing
Testing urine for albumin can help identify kidney damage in appropriate clinical settings.
Blood Pressure Measurement
Blood pressure assessment is important because high blood pressure and kidney disease are closely connected.
How to Protect Your Kidney Health
Kidney health depends on your overall health and management of conditions that can damage the kidneys. Healthy habits can support kidney health, while individual recommendations should be based on your medical situation.
Control Blood Pressure
Monitor your blood pressure and follow your healthcare professional's treatment plan when hypertension is present.
Manage Diabetes
Good diabetes management can help reduce the risk of kidney complications.
Maintain Healthy Hydration
Drink fluids appropriately for your individual needs and follow medical advice if you have a condition requiring fluid restriction.
Stay Physically Active
Regular physical activity and maintaining a healthy weight can support overall health and cardiovascular risk management.
Do not self-diagnose. If you have persistent urinary changes, swelling, blood in urine or important kidney-disease risk factors, discuss appropriate testing with a healthcare professional.
When Should You See a Doctor?
Seek medical advice when symptoms are persistent, unexplained or worsening. Some urinary symptoms can indicate conditions that need prompt treatment.
- Blood in the urine
- Persistent swelling
- Significant or unexplained changes in urination
- Persistent flank or lower-back pain
- Fever with urinary symptoms
- Unexplained persistent fatigue or weakness
Don't Ignore Possible Kidney Warning Signs
If you have persistent urinary changes, swelling, blood in urine or other concerning symptoms, professional evaluation can help identify the underlying cause.
Frequently Asked Questions
What are the first signs of kidney problems?
Early kidney disease may have no noticeable symptoms. When symptoms do occur, they can include changes in urination, swelling, tiredness and other nonspecific symptoms. Testing is often more useful than symptoms alone for identifying kidney disease.
Can kidney disease exist without symptoms?
Yes. Many people with early chronic kidney disease do not have obvious symptoms. This is why people with relevant risk factors may be advised to have appropriate blood and urine testing.
Is foamy urine always a sign of kidney disease?
No. Foamy urine can have several causes. Persistent or unusually excessive foam may warrant medical evaluation, particularly when other symptoms or risk factors are present.
Is blood in urine related to kidney problems?
Blood in urine can occur with kidney and urinary-tract conditions, including stones, infections and other causes. Unexplained blood in urine should be medically evaluated.
Which tests are used to check kidney function?
Depending on the situation, a healthcare professional may recommend blood creatinine testing, estimated GFR, urine albumin testing, urinalysis and blood-pressure measurement.
Medical Information & Disclaimer
This article is intended for general health education and should not replace a medical examination, diagnosis or personalised treatment plan. Symptoms described above can have many different causes.
General medical information for this article was checked against kidney-health resources from the U.S. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).