- Acute Kidney Failure
- Chronic Kidney Failure
<Acute Kidney Failure>
Acute kidney failure occurs when your kidneys suddenly become unable to filter waste products from your blood. When your kidneys lose their filtering ability, dangerous levels of wastes may accumulate and your blood's chemical makeup may get out of balance.
Acute kidney failure — also called acute renal failure or acute kidney injury — develops rapidly over a few hours or a few days. Acute kidney failure is most common in people who are already hospitalized, particularly in critically ill people who need intensive care.
Acute kidney failure can be fatal and requires intensive treatment. However, acute kidney failure may be reversible. If you're otherwise in good health, you may recover normal kidney function.
Signs and symptoms of acute kidney failure may include:
- Decreased urine output
- Swelling in your legs, ankles or feet
- Shortness of breath
- Seizures or coma in severe cases
Sometimes acute kidney failure causes no signs or symptoms and is detected through lab tests done for another reason.
When to see a doctor
Make an appointment with your primary care doctor if you have any signs or symptoms of acute kidney failure.
Acute kidney failure can occur when:
- You have a condition that slows blood flow to your kidneys
- You experience direct damage to your kidneys
- Your kidneys' urine drainage tubes (ureters) become blocked and wastes can't leave your body through your urine
Acute kidney failure almost always occurs in connection with another medical condition or event. Conditions that can increase your risk of acute kidney failure include:
- Being hospitalized, especially for a serious condition that requires intensive care
- Advanced age
- Blockages in the blood vessels in your arms or legs (peripheral artery disease)
- High blood pressure
- Heart failure
- Kidney diseases
- Liver diseases
Potential complications of acute kidney failure include:
- Fluid buildup. Acute kidney failure may lead to a buildup of fluid in your chest, which can cause shortness of breath.
- Muscle weakness. When your body's fluids and electrolytes — your body's blood chemistry — are out of balance, muscle weakness can result. Elevated levels of potassium in your blood are particularly dangerous.
- Permanent kidney damage. Occasionally, acute kidney failure causes permanent loss of kidney function, or end-stage renal disease. People with end-stage renal disease require either permanent dialysis — a mechanical filtration process used to remove toxins and wastes from your body — or a kidney transplant to survive.
- Death. Acute kidney failure can lead to loss of kidney function and, ultimately, death. The risk of death is highest in people who had kidney problems before acute kidney failure.
Most people are already hospitalized when they develop acute kidney failure. If you aren't in the hospital, but have signs or symptoms of kidney failure, make an appointment with your primary care doctor. If your doctor suspects you have kidney problems, you may be referred to a doctor who specializes in kidney disease (nephrologist).
If your signs and symptoms suggest that you have acute kidney failure, your doctor may recommend tests and procedures to verify your diagnosis. These may include:
- Urine tests. Analyzing a sample of your urine, a procedure called urinalysis, may reveal abnormalities that suggest kidney failure.
- Blood tests. A sample of your blood may reveal rapidly rising levels of urea and creatinine — two substances used to measure kidney function.
- Imaging tests. Imaging tests such as ultrasound and computerized tomography (CT) may be used to help your doctor see your kidneys.
- Removing a sample of kidney tissue for testing. In certain situations, your doctor may recommend a kidney biopsy to remove a small sample of kidney tissue for lab testing. To remove a sample of kidney tissue, your doctor may insert a thin needle through your skin and into your kidney.
Treatment for acute kidney failure typically requires a hospital stay. Most people with acute kidney failure are already hospitalized. How long you'll stay in the hospital depends on the reason for your acute kidney failure and how quickly your kidneys recover. Your doctor will also work to prevent complications and allow your kidneys time to heal. Treatments that help prevent complications include:
- Treatments to balance the amount of fluids in your blood. If your acute kidney failure is caused by a lack of fluids in your blood, your doctor may recommend intravenous (IV) fluids. In other cases, acute kidney failure may cause you to have too much fluid, leading to swelling in your arms and legs. In these cases, your doctor may recommend medications (diuretics) to cause your body to expel extra fluids.
- Medications to control blood potassium. If your kidneys aren't properly filtering potassium from your blood, your doctor may prescribe calcium, glucose or sodium polystyrene sulfonate (Kayexalate, Kionex) to prevent the accumulation of high levels of potassium in your blood. Too much potassium in the blood can cause dangerous irregular heartbeats (arrhythmias) and muscle weakness.
- Medications to restore blood calcium levels. If the levels of calcium in your blood drop too low, your doctor may recommend an infusion of calcium.
- Dialysis to remove toxins from your blood. If toxins build up in your blood, you may need temporary hemodialysis — often referred to simply as dialysis — to help remove toxins and excess fluids from your body while your kidneys heal. Dialysis may also help remove excess potassium from your body. During dialysis, a machine pumps blood out of your body through an artificial kidney (dialyzer) that filters out waste. The blood is then returned to your body.
During your recovery from acute kidney failure, your doctor may recommend a special diet to help support your kidneys and limit the work they must do.
- Choose lower potassium foods. Your dietitian may recommend that you choose lower potassium foods. High-potassium foods include beans, potatoes, avocado, bananas, oranges, spinach and tomatoes.
- Avoid products with added salt. Lower the amount of sodium you eat each day by avoiding products with added salt, including many convenience foods, such as frozen dinners, canned soups and fast foods. Other foods with added salt include salty snack foods, canned vegetables, and processed meats and cheeses.
- Limit phosphorus. Phosphorus is a mineral found in foods such as milk, cheese, dried beans, nuts and peanut butter. Too much phosphorus in your blood can weaken your bones and cause skin itchiness.
Acute kidney failure is often difficult to predict or prevent. But you may reduce your risk by taking care of your kidneys. Try to:
- Follow instructions on over-the-counter (OTC) medications. Follow the instructions on OTC pain medications such as aspirin, acetaminophen (Tylenol, others) and ibuprofen (Advil, Motrin, others). Taking doses that are too high may increase your risk of acute kidney failure. This is especially true if you have pre-existing kidney disease, diabetes or high blood pressure.
- Work with your doctor to manage kidney problems. If you have kidney disease or other diseases or conditions that increase your risk of acute kidney failure, such as diabetes or high blood pressure, follow your doctor's recommendations for managing your condition.
- Make a healthy lifestyle a priority. Be active; eat a sensible, balanced diet; and drink alcohol only in moderation — if at all.
<Chronic Kidney Failure>
Chronic kidney disease, also called chronic kidney failure, describes the gradual loss of kidney function. Your kidneys filter wastes and excess fluids from your blood, which are then excreted in your urine. When chronic kidney disease reaches an advanced stage, dangerous levels of fluid, electrolytes and wastes can build up in your body.
In the early stages of chronic kidney disease, you may have few signs or symptoms. Chronic kidney disease may not become apparent until your kidney function is significantly impaired.
Treatment for chronic kidney disease focuses on slowing the progression of the kidney damage, usually by controlling the underlying cause. Chronic kidney disease can progress to end-stage kidney failure, which is fatal without artificial filtering (dialysis) or a kidney transplant.
Signs and symptoms of chronic kidney disease develop over time if kidney damage progresses slowly.
- Loss of appetite
- Fatigue and weakness
- Sleep problems
- Changes in urine output
- Decreased mental sharpness
- Muscle twitches and cramps
- Swelling of feet and ankles
- Persistent itching
- High blood pressure (hypertension) that's difficult to control
Signs and symptoms of kidney disease are often nonspecific, meaning they can also be caused by other illnesses. And because your kidneys are highly adaptable and able to compensate for lost function, signs and symptoms may not appear until irreversible damage has occurred.
When to see a doctor
Make an appointment with your doctor if you have any signs or symptoms of kidney disease.
If you have a medical condition that increases your risk of chronic kidney disease, your doctor is likely to monitor your blood pressure and kidney function with urine and blood tests during regular office visits.
Chronic kidney disease occurs when a disease or condition impairs kidney function, causing kidney damage to worsen over several months or years.
Factors that may increase your risk of chronic kidney disease include:
- High blood pressure
- Heart disease
- High cholesterol
- Family history of kidney disease
- Age 65 or older
Chronic kidney disease can affect almost every part of your body. Potential complications may include:
- Fluid retention, which could lead to swelling in your arms and legs, high blood pressure, or fluid in your lungs
- A sudden rise in potassium levels in your blood, which could impair your heart's ability to function and may be life-threatening
- Heart and blood vessel disease
- Weak bones and an increased risk of bone fractures
- Decreased sex drive or impotence
- Damage to your central nervous system, which can cause difficulty concentrating, personality changes or seizures
- Decreased immune response, which makes you more vulnerable to infection
- Pregnancy complications that carry risks for the mother and the developing fetus
- Irreversible damage to your kidneys (end-stage kidney disease), eventually requiring either dialysis or a kidney transplant for survival
You'll likely start by seeing your primary care doctor if you have signs or symptoms of kidney disease. If lab tests reveal you have kidney damage, you may be referred to a doctor who specializes in kidney problems (nephrologist).
What you can do
To get ready for your appointment, ask if there's anything you need to do ahead of time, such as limit your diet. Then make a list of:
- Your symptoms
- All your medications and doses, vitamins or other supplements that you take
- Your key medical history, including any other medical conditions
To determine whether you have chronic kidney disease, you may need tests and procedures such as:
- Blood tests. Kidney function tests look for the level of waste products, such as creatinine and urea, in your blood.
- Urine tests. Analyzing a sample of your urine may reveal abnormalities that point to chronic kidney failure and help identify the cause of chronic kidney disease.
- Imaging tests. Your doctor may use ultrasound to assess your kidneys' structure and size. Other imaging tests may be used in some cases.
- Removing a sample of kidney tissue for testing. Your doctor may recommend a kidney biopsy to remove a sample of kidney tissue. Kidney biopsy is often done with local anesthesia using a long, thin needle that's inserted through your skin and into your kidney. The biopsy sample is sent to a lab for testing to help determine what's causing your kidney problem.
Depending on the underlying cause, some types of kidney disease can be treated. Often, though, chronic kidney disease has no cure. In general, treatment consists of measures to help control signs and symptoms, reduce complications, and slow progression of the disease. If your kidneys become severely damaged, you may need treatment for end-stage kidney disease.
Your doctor will work to slow or control the cause of your kidney disease. Treatment options vary, depending on the cause. But kidney damage can continue to worsen even when an underlying condition, such as high blood pressure, has been controlled.
Treatments may include:
- High blood pressure medications. People with kidney disease may experience worsening high blood pressure. Your doctor may recommend medications to lower your blood pressure — commonly angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers — and to preserve kidney function. High blood pressure medications can initially decrease kidney function and change electrolyte levels, so you may need frequent blood tests to monitor your condition. Your doctor will likely also recommend a low-salt diet.
- Medications to lower cholesterol levels. Your doctor may recommend medications called statins to lower your cholesterol. People with chronic kidney disease often experience high levels of bad cholesterol, which can increase the risk of heart disease.
- Medications to treat anemia. In certain situations, your doctor may recommend supplements of the hormone erythropoietin, sometimes with added iron. Erythropoietin supplements aid in production of more red blood cells, which may relieve fatigue and weakness associated with anemia.
- Medications to relieve swelling. People with chronic kidney disease may retain fluids. This can lead to swelling in the legs, as well as high blood pressure. Medications called diuretics can help maintain the balance of fluids in your body.
- Medications to protect your bones. Your doctor may prescribe calcium and vitamin D supplements to prevent weak bones and lower your risk of fracture. You may also take medication to lower the amount of phosphate in your blood, to protect your blood vessels from damage by calcium deposits.
- A lower protein diet to minimize waste products in your blood. As your body processes protein from foods, it creates waste products that your kidneys must filter from your blood. To reduce the amount of work your kidneys must do, your doctor may recommend eating less protein.
If your kidneys can't keep up with waste and fluid clearance on their own and you develop complete or near-complete kidney failure, you have end-stage kidney disease. At that point, dialysis or a kidney transplant is needed.
- Dialysis. Dialysis artificially removes waste products and extra fluid from your blood when your kidneys can no longer do this. In hemodialysis, a machine filters waste and excess fluids from your blood. In peritoneal dialysis, a thin tube (catheter) inserted into your abdomen fills your abdominal cavity with a dialysis solution that absorbs waste and excess fluids. After a period of time, the dialysis solution drains from your body, carrying the waste with it.
- Kidney transplant. A kidney transplant involves surgically placing a healthy kidney from a donor into your body. Transplanted kidneys can come from deceased or living donors. You'll need to take medications for the rest of your life to keep your body from rejecting the new organ.
For some who choose not to have dialysis or a kidney transplant, a third option is to treat your kidney failure with conservative measures. However, once you have complete kidney failure, your life expectancy generally would be only a few weeks.
Receiving a diagnosis of chronic kidney disease can be worrisome. You may be concerned about what your diagnosis means for your future health. To help you cope with your feelings, consider trying to:
- Connect with other people who have kidney disease. Other people with chronic kidney disease understand what you're feeling and can offer unique support. Contact organizations such as the American Association of Kidney Patients, the National Kidney Foundation or the American Kidney Fund for groups in your area.
- Maintain your normal routine, when possible. Try to maintain a normal routine, doing the activities you enjoy and continuing to work, if your condition allows. This may help you cope with feelings of sadness or loss that you may experience after your diagnosis.
- Be active most days of the week. With your doctor's advice, aim for at least 30 minutes of physical activity most days of the week. This can help you cope with fatigue and stress.
- Talk with a person you trust. Living with chronic kidney disease can be stressful, and it may help to talk about your feelings. You may have a friend or family member who is a good listener. Or you may find it helpful to talk with a faith leader or someone else you trust. Ask your doctor for a referral to a social worker or counselor.
To reduce your risk of chronic kidney disease:
- Drink alcohol in moderation, if at all. If you choose to drink alcohol, do so in moderation. For healthy adults, that means no more than one drink a day for women of all ages and men older than 65, and no more than two drinks a day for men 65 and younger.
- Follow instructions on over-the-counter medications. When using nonprescription pain relievers, such as aspirin, ibuprofen (Advil, Motrin, others) and acetaminophen (Tylenol, others), follow the instructions on the package. Taking too many pain relievers could lead to kidney damage and generally should be avoided if you have kidney disease.
- Maintain a healthy weight. If you're at a healthy weight, work to maintain it by being physically active most days of the week. If you need to lose weight, talk with your doctor about strategies for healthy weight loss. Often this involves increasing daily physical activity and reducing calories.
- Don't smoke. If you're a smoker, talk to your doctor about strategies for quitting smoking. Support groups, counseling and medications can all help you to stop.
- Manage your medical conditions with your doctor's help. If you have diseases or conditions that increase your risk of kidney disease, work with your doctor to control them.