Acute kidney failure occurs when your kidneys suddenly become unable to filter waste products from your blood. When your kidneys lose their ability to filter, dangerous levels of waste can accumulate, and the chemical makeup of your blood can be out of balance.
Kidney failure — also called acute kidney failure or acute kidney injury — develops rapidly, usually over less than a few days. Acute renal failure is most common in people who are already hospitalized, especially in those seriously ill who require intensive care.
Acute renal failure can be fatal and requires intensive treatment. However, acute renal failure can be reversible. If you are in otherwise good health, you can recover normal or near-normal kidney function.
Signs and symptoms of acute kidney failure may include:
- Shortness of breath
- Decreased urine output, although occasionally urine output remains normal
- Fluid retention, causing swelling in your legs, ankles or feet
- Irregular heartbeat
- Seizures or coma in severe cases
- Chest pain or pressure
Sometimes acute kidney failure has no signs or symptoms and is diagnosed through laboratory tests done for another cause.
Acute kidney failure can occur when:
- You experience direct damage to your kidneys
- You have a condition that slows blood flow to your kidneys
- Your kidneys’ urine drainage tubes (ureters) become blocked and wastes can’t leave your body through your urine
Impaired blood flow to the kidneys
Diseases and conditions that may slow blood flow to the kidneys and lead to kidney injury include:
- Heart attack
- Blood or fluid loss
- Heart disease
- Blood pressure medications
- Severe allergic reaction (anaphylaxis)
- Liver failure
- Severe burns
- Severe dehydration
- Use of aspirin, ibuprofen (Advil, Motrin IB, others), naproxen sodium (Aleve, others) or related drugs
Damage to the kidneys
These diseases, conditions and agents may damage the kidneys and lead to acute kidney failure:
- Cholesterol deposits that block blood flow in the kidneys
- Blood clots in the veins and arteries in and around the kidneys
- Hemolytic uremic syndrome, a condition that results from premature destruction of red blood cells
- Glomerulonephritis (gloe-mer-u-loe-nuh-FRY-tis), inflammation of the tiny filters in the kidneys (glomeruli)
- Infection, such as with the virus that causes coronavirus disease 2020 (COVID-19)
- Medications, such as certain chemotherapy drugs, antibiotics and dyes used during imaging tests
- Thrombotic thrombocytopenic purpura, a rare blood disorder
- Scleroderma, a group of rare diseases affecting the skin and connective tissues
- Toxins, such as alcohol, heavy metals and cocaine
- Breakdown of tumor cells (tumor lysis syndrome), which leads to the release of toxins that can cause kidney injury
Urine blockage in the kidneys
Diseases and conditions that block the passage of urine out of the body (urinary blockage) and can cause acute kidney injury:
- Bladder cancer
- Cervical cancer
- Blood clots in the urinary tract
- Colon cancer
- Kidney stones
- Enlarged prostate
- Nerve damage involving the nerves that control the bladder
- Prostate cancer
Acute renal failure almost always occurs in relation to another medical condition or event. Conditions that increase your risk of acute kidney failure include:
- Being hospitalized, especially for a serious condition that requires intensive care
- Blockages in the blood vessels in your arms or legs (peripheral artery disease)
- Advanced age
- Heart failure
- Certain cancers and their treatments
- High blood pressure
- Liver diseases
- Kidney diseases
Potential complications of acute kidney failure include:
- Muscle weakness. When your body’s fluids and electrolytes — your body’s blood chemistry — are out of balance, muscle weakness can occur.
- Fluid buildup. Acute kidney failure may lead to a buildup of fluid in your lungs, which can cause shortness of breath.
- Permanent kidney damage. Sometimes, acute kidney failure causes permanent loss of kidney function or leads to end-stage kidney disease. People with end-stage kidney disease need either permanent dialysis — a mechanical filtration process used to remove toxins and wastes from the body — or a kidney transplant to survive.
- Chest pain. If the lining that covers your heart (pericardium) becomes inflamed, you may experience chest pain.
- Death. Kidney failure can lead to loss of kidney function and, ultimately, death.
Acute kidney failure is often difficult to predict or prevent. But you may reduce your risk by taking care of your kidneys. Try to:
- Work with your doctor to manage kidney and other chronic conditions.If you have kidney disease or another condition that increases your risk of acute kidney failure, such as diabetes or high blood pressure, stay on track with treatment goals and your doctor’s recommendations to manage your condition.
- Pay attention to labels when taking over-the-counter (OTC) pain medications.Follow the directions for OTC pain relievers, such as aspirin, acetaminophen (Tylenol, others), ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve, others). Taking too much of these drugs can increase your risk of kidney injury. This is especially true if you already have kidney disease, diabetes or high blood pressure.
- Make a healthy lifestyle a priority. Be active; eat a sensible, balanced diet; and drink alcohol only in moderation — if at all.