Acute kidney injury (AKI) is a sudden drop in kidney function that happens over hours or days. Waste products and fluid can build up in the body, and the balance of minerals such as potassium can be thrown off. AKI is often found in the hospital, but it can also happen at home, for example during a bad illness with vomiting or diarrhea.
Common causes
- Not enough blood flow to the kidneys: dehydration, heavy bleeding, low blood pressure, severe infection (sepsis), or heart failure
- Direct injury to the kidneys: some medicines (such as NSAID pain relievers and certain antibiotics), contrast dye used for some scans, infections, or inflammation in the kidneys
- A blockage of urine flow: an enlarged prostate, kidney stones, or tumors
Who is at higher risk
- Adults over 65
- People with chronic kidney disease, diabetes, high blood pressure, heart disease, or liver disease
- People who are very sick or in the hospital, especially in intensive care
Symptoms
AKI may cause no symptoms and be found only on blood tests. When symptoms happen, they can include passing less urine, swelling in the legs or around the eyes, tiredness, confusion, nausea, shortness of breath, or chest pressure.
How it is diagnosed and treated
AKI is diagnosed with blood tests (a rise in creatinine), measuring urine output, urine tests, and sometimes a kidney ultrasound. Treatment focuses on the cause: restoring fluids and blood pressure, stopping medicines that can harm the kidneys, treating infection, or relieving a blockage. Fluid, potassium, and acid levels are watched closely. Some people need dialysis for a short time while the kidneys recover.
After an episode of AKI
Many people recover most or all of their kidney function. But AKI raises the risk of chronic kidney disease and of another kidney injury later, so follow-up care matters.
- Get your kidney blood tests rechecked in the weeks to months after you leave the hospital.
- Bring all your medicines to your visit so doses can be reviewed for your kidney function.
- Avoid NSAIDs such as ibuprofen and naproxen unless your doctor says they are safe.
- When you are sick with vomiting, diarrhea, or fever and cannot keep fluids down, call your doctor. Some medicines may need to be paused for a few days.
Questions to ask at your visit
- What caused my kidney injury?
- Has my kidney function recovered, and when should it be checked again?
- Which of my medicines should I stop or adjust?
- What should I do if I get sick again?
This guide is general education and is not a substitute for medical advice. Talk with Dr. Salim or your care team about your own situation. Informed by patient materials from the National Kidney Foundation; learn more at kidney.org.