A Guide to Acute Renal Failure

Medically Reviewed By Alana Biggers, M.D., MPH
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Acute renal failure (ARF), also known as acute kidney injury, means that kidneys are damaged. ARF could occur in several hours or days. The damage makes it difficult for your body to filter waste products and keep beneficial particles in your blood. The kidneys sit on either side of your spine toward your back. They clean the blood that flows through them and waste products passing through urine. The kidneys also make hormones that regulate blood pressure. When you have ARF, your kidneys cannot function as they should, and waste products can build up in your body.

Read on to learn more about the causes, symptoms, and treatment for acute renal failure.

What are the causes of acute renal failure?

A woman looking tired

According to the National Kidney Foundation, ARF can have many causes. These causes may include:

  • swollen kidney from infection or a medication reaction 
  • overuse of nonsteroidal anti-inflammatory drugs (NSAIDs)
  • certain cancers such as multiple myeloma
  • blockages from kidney stones or tumors
  • reduced blood flow from injury or major surgery
  • heart attack or failure
  • high blood pressure

What are the symptoms of acute renal failure?

Symptoms of ARF depend on the cause, how significant the damage is, and how quickly the condition progresses. Some people may not realize they have ARF because they do not have symptoms. When symptoms do occur, they can include:

In more serious instances of ARF, you may experience seizures or a coma.

How do doctors diagnose acute renal failure?

To diagnose ARF, doctors usually start with a physical examination and an assessment of your medical history. If you recently experienced illness, your doctor may ask about factors that could indicate dehydration, such as diarrhea or vomiting

A physical exam and medical history are important in the diagnostic process because blood tests alone do not typically indicate the cause of ARF. However, your doctor may order tests that can check certain levels and markers in your blood:

  • Electrolyte levels: Atypical levels of electrolytes — such as sodium and potassium — can show that your kidneys are not working properly. 
  • Creatinine: Higher than average creatinine levels can indicate that your kidneys are not filtering it out of your bloodstream.
  • Blood urea nitrogen: This test measures the urea nitrogen in the blood. Higher levels can indicate your kidneys are not functioning as they should.
  • Estimated glomerular filtration rate (eGFR): The eGFR can indicate how well your kidneys work.

You may also have a urinalysis (UA), when you will collect your urine in a sterile cup for analysis in a laboratory. A UA can show how concentrated your urine is, if particles such as white blood cells are present, and if the urine is cloudy or clear. 

An ultrasound or other imaging test can help your doctor assess your kidneys and their structures. Sometimes a kidney biopsy is necessary.

Your doctor may also have you undergo a fluid challenge, when they will rapidly administer a small amount of fluid intravenously. This test can help doctors determine the type and extent of your kidney damage.

What are the treatments for acute renal failure? 

It is important to find and treat the cause of ARF. The treatment you receive will depend on several factors, including the amount of damage to the kidneys. 

Medical treatments

Most people who have ARF are already in the hospital. However, if you receive an ARF diagnosis at home or during an appointment with your doctor, they will likely recommend hospitalization. 

For more serious kidney damage, you may need to undergo dialysis. This procedure filters out waste products from your kidneys using a machine, similar to how your kidneys remove waste. While the machine removes waste, it also keeps certain beneficial particles in your blood and helps keep your blood pressure under control.  

In severe cases, treating ARF involves a kidney transplant. About 6,000 people receive a kidney transplant from a living donor every year, and 10,000 people receive a transplant from deceased donors.

Lifestyle changes

If you have ARF, your doctor may recommend a diet that is low in sodium and possibly protein. Damaged kidneys may have difficulty filtering out protein waste. The Dietary Approaches to Stop Hypertension (DASH) diet consists of:

  • fruits and vegetables
  • low fat dairy
  • fish and poultry
  • whole grains
  • beans
  • seeds and nuts

If you receive dialysis, do not use the DASH diet and work with a registered dietitian to determine your specific dietary needs. 

What is the outlook for people with acute renal failure?

With prompt treatment, the outlook for people with ARF is generally good. By working closely with a healthcare team, many people can make a full recovery.

If you had ARF before, you have an increased chance of experiencing it again. You also have a higher chance of other health conditions such as heart problems, stroke, or kidney disease. 

In some cases, doctors may miss an ARF diagnosis. This can often lead to reduced outcomes. In addition, many people with ARF receive their diagnosis in the later stages of the condition. 

What are some potential complications of acute renal failure?

If not treated, ARF can lead to complications such as:

ARF can also cause delays in certain procedures, such as imaging tests. These tests use contrast dye that the kidneys cannot efficiently filter out. 

Since most medications pass through the kidneys, doctors may need to adjust the dosages of your current or future medications due to decreased kidney function. Some medications — such as the antibiotic vancomycin — will require regular blood tests for monitoring. 

What are the risk factors for acute renal failure?

Certain factors and health conditions can increase your chances of developing ARF, including:

Can you prevent acute renal failure?

Finding the cause of any kidney malfunction and receiving prompt treatment can help you prevent ARF and reduce your chances of serious kidney damage. In addition, eating a balanced diet and exercising regularly can keep you in good overall health and may prevent ARF. 

If you have other health conditions like heart disease or diabetes, work with your healthcare professional to manage your condition.


ARF involves sudden damage to your kidneys. Overuse of NSAIDs, blood pressure changes, and injuries are possible causes of ARF. Common symptoms include swelling in your extremities, fatigue, and changes in your urination habits.

The treatment you receive depends on what is causing your kidney damage. Treatment may include dialysis or a kidney transplant in severe cases. 

With proper care and management, many people can recover. However, ARF can increase your chances of future kidney problems. Talk with your doctor if you are experiencing symptoms of kidney damage to receive treatment as soon as possible. 

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Medical Reviewer: Alana Biggers, M.D., MPH
Last Review Date: 2022 Jun 20
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. Acute kidney injury (AKI). (n.d.). https://www.kidney.org/atoz/content/AcuteKidneyInjury
  2. Dialysis. (n.d.). https://www.kidney.org/atoz/content/dialysisinfo
  3. Goyal, A., et al. (2022). Acute kidney injury. https://www.ncbi.nlm.nih.gov/books/NBK441896/
  4. Hertzberg, D. et al. (2017). Acute kidney injury—an overview of diagnostic methods and clinical management. https://academic.oup.com/ckj/article/10/3/323/3072617
  5. Social determinants of kidney disease. (n.d.). https://www.kidney.org/atoz/content/kidneydiscauses
  6. The DASH diet. (n.d.). https://www.kidney.org/atoz/content/Dash_Diet
  7. What is kidney (renal) failure? (n.d.). https://www.urologyhealth.org/urology-a-z/k/kidney-(renal)-failure