Acute Kidney Failure: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Acute Kidney Failure?
A nephrologist (a kidney doctor) treats acute kidney failure. A primary care doctor helps with follow-up. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is acute kidney failure?
Acute kidney failure is the rapid loss of your kidneys' ability to remove waste and help balance fluids and electrolytes in your body. Doctors also call it acute kidney injury, or AKI. The older name was acute renal failure.
It comes on fast, within hours or days. Healthy kidneys clean your blood by removing wastes and extra fluid. When they stop working, harmful wastes can build up.
Symptoms
Symptoms can differ by the cause and how severe it is. They may include:
- Making less urine (pee) than usual, or no urine.
- Swelling in the legs, ankles, or feet.
- Fatigue or tiredness.
- Shortness of breath (trouble breathing).
- Confusion or mood changes.
- Flank pain (pain on the side of your back).
Severe cases can cause seizures or coma. Nausea, less desire to eat, and chest pain or pressure can also happen. In some cases, AKI causes no symptoms and is only found through tests.
Causes and who gets it
AKI has many causes. Usually, it happens because of a combination of factors. This is especially true for older adults, who are at higher risk.
Blood flow to the kidneys can drop too low. Causes include hypotension (very low blood pressure) or shock, severe dehydration, hemorrhage (severe loss of blood), injury, major surgery, sepsis (a dangerous body-wide infection), and severe burns.
Medicines and other substances can also play a part. These include certain antibiotics, certain blood pressure medicines, and NSAIDs (non-steroidal anti-inflammatory drugs, pain relievers like ibuprofen), especially at higher doses. Contrast dye (dye used for CT scans) and some cancer or HIV medicines can also raise risk. These things may not cause AKI by themselves. But with other factors, your risk goes up a lot.
A blockage stops urine from flowing. Kidney stones, some cancers, and urinary tract blockage cause AKI. Kidney problems can also cause AKI. Examples are autoimmune kidney disease (such as glomerulonephritis, lupus, or IgA nephropathy), kidney infection, and multiple myeloma (a blood cancer).
How doctors diagnose it
Your health care team will look for the cause. They may do a physical exam and review your medicines, including ones you bought without a prescription. Common tests include:
- Serum (blood) creatinine, a blood test that shows how well the kidneys filter this waste product.
- BUN (blood urea nitrogen), another waste product measured in blood.
- eGFR (estimated glomerular filtration rate), a number that estimates kidney function.
- Blood tests for electrolytes, such as sodium and potassium.
- A urinalysis (a urine test) for clues about the cause.
- An ultrasound, the preferred test for finding a blockage in the urinary tract.
A CT scan or MRI of the abdomen can also tell if there is a blockage. In some less common situations, a doctor may take a tiny piece of kidney to look at under a microscope.
Treatment
Treatment for AKI depends on what caused it. Most people need time in the hospital while they get treatment. Care may include stopping any medicines that may be causing or adding to the AKI. Follow your doctor's instructions. Do not stop any medicine on your own.
Other care includes fluids, by mouth or through a vein, and antibiotics if a bacterial infection caused the AKI. If a blockage caused it, a urine catheter (a thin tube that drains the bladder) may help. A doctor may also limit how much you drink and change your diet while you heal.
Dialysis may be needed, depending on the damage. It does what healthy kidneys do. It removes harmful wastes, extra salt, and water from the body. It can save your life if your potassium levels are dangerously high. In most cases, dialysis is only temporary until the kidneys can recover.
When to see a doctor
Contact your doctor if your urine output slows or stops, or if you have other symptoms of acute kidney failure. Without treatment, AKI can affect other organs such as the brain, heart, and lungs. Call 911 or go to the emergency room if you have chest pain or discomfort lasting two minutes or more, new confusion, seizures, or trouble breathing.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. This kind of doctor can check your medicines, order kidney blood tests, and help with follow-up after a hospital stay.
Common questions
Can the kidneys recover after acute kidney failure?
Often they can. The goal of treatment is to help your kidneys work again and prevent fluid and waste from building up. In most cases, dialysis treatments are only temporary until the kidneys can recover.
Will it come back or cause other problems?
After having AKI, you are at a higher risk of getting AKI again in the future. You also have a higher risk for chronic kidney disease (CKD), heart disease, or stroke.
How can I lower my risk?
Health problems such as high blood pressure or diabetes should be well controlled. Avoid drugs and medicines that can cause kidney injury.
Will I need follow-up care?
Yes. After treatment, it is important to have regular follow-up visits and check your kidney health with two simple tests, ideally within 3 months of finishing treatment for your AKI.
Sources
- MedlinePlus - Acute kidney failure
- National Kidney Foundation - Acute Kidney Injury (AKI): Causes, Symptoms, and Treatment
- MedlinePlus - Kidney Failure
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
