Your kidneys are a pair of organs located in the region of your lower back. One kidney is on each side of your spine. Your kidneys filter your blood and remove toxins from your body. These toxins go to your bladder and are eliminated when you urinate. Kidney failure occurs when your kidneys lose their ability to sufficiently filter waste from your blood.

Many factors can interfere with your kidney health and function, such as:

  • certain acute and chronic diseases
  • toxic exposure to environmental pollutants or certain medications
  • severe dehydration
  • insufficient blood flow to the kidneys
  • kidney trauma

If your kidneys aren’t able to function properly, your body becomes overloaded with toxins. This can lead to kidney failure, which can be life threatening if left untreated.

Keep reading as we break down everything you need to know about kidney failure, including symptoms, stages, treatment, and the typical outlook.

Five different types of kidney failure exist. Acute kidney failure occurs when your kidneys suddenly stop working properly. Chronic kidney failure occurs over time.

The five types of kidney failure include:

  • Acute prerenal kidney failure. Insufficient blood flow to the kidneys can cause acute prerenal kidney failure. The kidneys can’t filter toxins from the blood without enough blood flow. This type of kidney failure can usually be cured once the cause of the decreased blood flow is determined.
  • Acute intrinsic kidney failure. Acute intrinsic kidney failure can result from direct trauma to the kidneys, such as physical impact or an accident. Other causes include toxin overload and ischemia, which is a lack of oxygen to the kidneys. Ischemia can be caused by severe bleeding, shock, obstruction of the renal blood vessel, and glomerulonephritis, a condition where the tiny blood vessels in your kidneys become inflamed.
  • Chronic prerenal kidney failure. When there isn’t enough blood flowing to your kidneys for an extended period of time, the kidneys begin to shrink and lose the ability to function.
  • Chronic intrinsic kidney failure. This happens when there’s long-term damage to the kidneys due to intrinsic kidney disease. Intrinsic kidney disease develops from a direct trauma to the kidneys, such as severe bleeding or a lack of oxygen.
  • Chronic post-renal kidney failure. A long-term blockage of the urinary tract prevents urination. This causes pressure and eventual kidney damage.

Early stage kidney failure often doesn’t cause noticeable symptoms. According to the Centers for Disease Control and Prevention (CDC), as many as 90 percent of people with chronic kidney disease don’t know they have it.

As kidney disease progresses, possible symptoms may include:

Early signs of kidney failure

Symptoms of early stage kidney disease may be difficult to pinpoint. They’re often subtle and hard to identify. If you experience early signs of kidney disease, they may include:

Kidney failure urine color

The color of your urine is a small window into your body’s health. It doesn’t tell you much about the state of your kidney function until damage to the kidneys has progressed.

Still, urine color changes may be a warning sign of some issues.

  • Clear or pale yellow. Clear or pale yellow urine indicates you’re well hydrated. This is the ideal color in most cases.
  • Dark yellow or amber. You may be dehydrated. Try drinking more water and cutting down on dark sodas, tea, or coffee.
  • Orange. This could be a sign of dehydration, or it might be a sign of bile in your bloodstream. Kidney disease doesn’t typically cause this.
  • Pink or red. Urine with a pink tint or a bit of red could have blood in it. It could also be caused by certain foods, like beets or strawberries. A quick urine test can tell the difference.
  • Foamy. Urine with excess bubbles is a sign that it likely has a lot of protein in it. Protein in urine is a sign of kidney disease.

Urine color can raise flags for potential problems. Learn about the common color causes and what’s most likely to affect the shade of your pee.

Kidney failure can be the result of several conditions or causes. According to the National Kidney Foundation, the two most common causes are high blood pressure and diabetes.

People who are most at risk usually have one or more of the following.

Loss of blood flow to the kidneys

A sudden loss of blood flow to your kidneys can prompt kidney failure. Some conditions that cause loss of blood flow to the kidneys include:

High blood pressure and anti-inflammatory medications can also limit blood flow.

Urine elimination problems

When your body can’t eliminate urine, toxins build up and overload the kidneys. Some cancers can block the urine passageways, such as:

Other conditions can interfere with urination and possibly lead to kidney failure, including:

Other causes

Some other factors that may lead to kidney failure include:

Your doctor can use several tests to diagnose kidney failure. Some of the most common tests include the following:

  • Urinalysis. Your doctor may take a urine sample to test for anything unusual, including atypical protein or sugar that spills into your urine. Your doctor may also perform a urinary sediment examination to look for red and white blood cells, high levels of bacteria, and high numbers of tube shaped particles called cellular casts.
  • Urine volume measurements. Measuring urine output is one of the simplest tests to help diagnose kidney failure. For example, low urinary output may suggest that kidney disease is due to a urinary blockage, which can be caused by multiple illnesses or injuries.
  • Blood samples. Your doctor may order blood tests to measure substances that are filtered by your kidneys, such as blood urea nitrogen and creatinine. A rapid rise in these levels may indicate acute kidney failure.
  • Imaging. Tests like ultrasounds, MRIs, and CT scans provide images of your kidneys and urinary tract to identify blockages or other problems.
  • Kidney tissue sample. Tissue samples are examined for unusual deposits, scarring, or infectious organisms. Your doctor will use a kidney biopsy to collect the tissue sample.

Kidney disease is classified into five stages. These range from very mild (stage 1) to complete kidney failure (stage 5). Symptoms and complications increase as the stages progress.

Stage 1

This stage is very mild. You may experience no symptoms and have no visible complications. Some kidney damage is present.

It’s still possible to manage and slow progression by maintaining a healthy lifestyle. This includes eating a balanced diet, exercising regularly, and not using tobacco products. Maintaining a moderate weight is important, too.

If you have diabetes, it’s important to manage your blood sugar.

Stage 2

Stage 2 kidney disease is still considered a mild form, but detectable issues like protein in urine or physical damage to the kidneys may be more obvious.

The same lifestyle approaches that helped in stage 1 are still used in stage 2. It’s also a good idea to talk with your doctor about other risk factors that could make the disease progress more rapidly, such as heart disease, inflammation, and blood disorders.

Stage 3

At this stage, your kidneys aren’t working as well as they should.

Stage 3 kidney disease is sometimes divided into stages 3a and 3b. A blood test that measures the amount of waste products in your body helps doctors differentiate between the two.

Symptoms may become more apparent at this stage. Swelling in hands and feet, back pain, and changes to urination frequency are likely.

Lifestyle approaches may help improve symptoms. Your doctor may also consider medications to treat underlying conditions that could speed up kidney failure.

Stage 4

Stage 4 kidney disease is considered moderate to severe. The kidneys aren’t working well, but you’re not in complete kidney failure yet. Symptoms can include complications like anemia, high blood pressure, and bone disease.

A healthy lifestyle is still vital. Your doctor will likely develop a treatment plan designed to slow kidney damage.

Stage 5

In stage 5, your kidneys are nearing or in complete failure. Symptoms of the loss of kidney function will be evident, such as vomiting and nausea, trouble breathing, itchy skin, and more.

At this stage, you’ll need regular dialysis or a kidney transplant.

The National Institute of Diabetes and Digestive and Kidney Diseases estimates that approximately 1 in 500 Americans is living with stage 5 kidney failure.

Several treatment options are available for kidney failure. The type of treatment you need will depend on the cause of your kidney failure as well as the stage.

Dialysis

Dialysis filters and purifies the blood using a machine. The machine performs the function of the kidneys. Depending on the type of dialysis, you may be connected to a large machine or a portable catheter bag.

Along with dialysis, you may need to follow a low potassium, low salt diet.

Dialysis doesn’t cure kidney failure, but it can extend your life if you go to regularly scheduled treatments.

Kidney transplant

Another treatment option is a kidney transplant. A transplanted kidney can work fully, so you no longer need dialysis.

There’s usually a long wait to receive a donor kidney that’s compatible with your body. If you have a living donor, the process may go more quickly.

Transplant surgery might not be the right treatment option for everyone. It’s also possible for the surgery to be unsuccessful.

You must take immunosuppressant drugs after the surgery to prevent your body from rejecting the new kidney. These drugs have their own side effects, some of which can be serious.

Talk with your doctor about whether you’re a good candidate for a kidney transplant.

Lifestyle modifications

Minimizing your intake of alcohol and making certain dietary changes may help prevent your kidney failure from progressing to a more severe disease.

Lowering alcohol intake

If you have kidney failure and drink alcohol, your kidneys will be forced to work harder than they already do. Alcohol doesn’t metabolize out of your system, so you’ll feel its effects until you receive dialysis to filter it out of your blood.

Beer, ale, and wine also contain large amounts of phosphorous. Severe heart issues and even death are possible if your kidneys are unable to filter it out. However, most hard liquor doesn’t carry the same risk.

If you have kidney failure or late stage kidney disease, your doctor may recommend you limit how often you drink alcohol. For some people, completely eliminating alcohol from the diet may be best.

Dietary changes

There’s no specific diet for people with kidney failure. The guidelines for what you eat will often depend on the stage of kidney disease you have and your overall health. Some recommendations might include:

  • Limiting sodium and potassium. Keep track of how much of these two nutrients you’re taking in. Aim to eat less than 2,000 milligrams per day of both sodium (salt) and potassium.
  • Limiting phosphorus. Like sodium and potassium, it’s good to keep a cap on the amount of phosphorus you eat in a day. Based on a 2019 review, try to stay below 1,000 milligrams.
  • Following protein guidelines. In early and moderate kidney disease, you might want to cut back on protein consumption. In end stage kidney failure, however, you may eat more protein, depending on your doctor’s recommendations.

Beyond these general guidelines, your doctor may also ask you to avoid certain foods if you have kidney disease.

Without management, high blood sugar can damage your kidneys. The damage can worsen over time.

Diabetic nephropathy, or kidney damage caused by type 1 or type 2 diabetes, can’t be reversed. Managing your blood sugar and blood pressure may help prevent or limit kidney damage. Taking medications as prescribed by your doctor is important, too.

If you have diabetes, your doctor will likely perform regular screenings to monitor for kidney failure.

Your risk for diabetic nephropathy increases the longer you live with diabetes.

Diabetes is the most common cause of kidney failure. About one-third of adults with diabetes have kidney disease, according to the National Institute of Diabetes and Digestive and Kidney Diseases.

It’s not possible to know exactly how long a person with kidney failure will live. Every person with kidney failure is different.

In general, the National Kidney Foundation says that a person on dialysis can expect to live for an average of 5 to 10 years as long as they follow their treatment. Some people live for more than 20 or 30 years.

Factors that can play a role in life expectancy include your:

  • age
  • stage of kidney disease
  • other coexisting conditions

Once you reach end stage kidney failure, you will need dialysis or a kidney transplant to live. Missing even one dialysis treatment can decrease your life expectancy.

Kidney failure can lead to various complications, such as:

  • Anemia. When your kidneys aren’t working properly, your body may not be able to properly create red blood cells. Anemia is the medical term for a low red blood cell count.
  • Bone weakness. Damage to your kidneys can disrupt the balance of minerals in your body such as phosphorus and calcium. This imbalance can lead to weakened bones.
  • Fluid retention. If your kidneys aren’t able to adequately filter water out of your blood, you may be at risk of developing fluid retention, especially in your lower body.
  • Heart disease. Heart disease can lead to kidney failure, or kidney failure can lead to heart disease. According to a 2018 study, heart disease is the most common cause of death in people on dialysis.
  • Hyperkalemia. Kidney failure can lead to hyperkalemia, or elevated potassium levels. In extreme cases, hyperkalemia can lead to heart failure.
  • Metabolic acidosis. Disrupted kidney function can lead to metabolic acidosis, meaning your bodily fluids contain too much acid. Metabolic acidosis can cause complications such as kidney stones or bone disease.
  • Secondary complications. Many people with kidney failure develop secondary complications such as:

You can take steps to lower your risk of kidney failure.

Follow directions when taking over-the-counter medications. Taking doses that are too high, even of common drugs like aspirin, can create high toxin levels in a short amount of time. This can overload your kidneys.

Many kidney or urinary tract conditions lead to kidney failure when they’re not properly managed.

You can also help lower your risk of kidney failure by:

  • maintaining a healthy lifestyle
  • taking prescribed medications as directed and not taking more medication than is safe
  • keeping conditions, such as diabetes and high blood pressure, well managed and following your doctor’s advice

If you have any concerns about your kidney health, don’t hesitate to reach out to your doctor.

The prognosis, or outlook, for people with kidney failure varies widely depending on several factors. These include:

  • the underlying cause
  • how well that underlying cause is managed
  • any complicating factors, like high blood pressure or diabetes
  • stage of kidney disease at diagnosis

Proper treatment and healthy lifestyle changes may be able to improve your outlook. Eating a balanced diet, cutting back on kidney-damaging foods, lowering your alcohol consumption, and treating any underlying issues may help protect your health and extend your life.

Kidney failure can develop suddenly or due to long-term damage. There are many possible causes of kidney failure, including diabetes, high blood pressure, exposure to high levels of medication, extreme dehydration, kidney trauma, or other factors.

Kidney disease is classified into five stages. These range from very mild to complete kidney failure. Symptoms and complications increase as the stages progress.

If you have kidney failure, you can work with your doctor to determine the best treatment options for your condition.