Acute Kidney Injury
(AKI; Acute Kidney Failure; Acute Renal Failure; Acute Renal Insufficiency)
Madeline Vann, MPH
Acute kidney injury (AKI) is the sudden loss of kidney function. Kidneys clean wastes from the blood and maintain fluid levels in the body.
Problems can happen:
- Before blood enters the kidneys
- Inside the kidneys (most common)
- When urine leaves the kidneys and moves toward the bladder
Anatomy of the Kidney
Copyright © Nucleus Medical Media, Inc.
AKI has many causes:
Blood is blocked from going into the kidneys because of:
Problems inside the kidney cause tissue death because of:
- Problems after surgery
- Blood clots
- Medicine side effects
- Enlarged prostate
Risk Factors TOP
AKI is most common in older adults and females. Your chances are also higher if you have:
High blood pressure
- Kidney, liver, or heart disease
- Bleeding from the stomach or intestines
- Taken certain medicines
- Used illegal drugs
- Problems after surgery or a hospital stay
- Overused certain nonsteroidal anti-inflammatory drugs (NSAIDs)
- Used angiotensin converting enzyme (ACE) inhibitors
Blockages, which can happen with
benign prostatic hyperplasia
or a bladder tumor
Most people do not have symptoms. In those that have them, AKI may cause:
- Lower or higher amounts of urine than normal
- Nausea or vomiting
- Muscle weakness
- Muscle cramps
- Lack of hunger
- Weight gain
The doctor will ask about your symptoms and health history. You may also have:
- A physical exam
- Blood and urine tests—to look for levels of certain proteins
You may be referred to a specialist for care.
Care depends on the cause of AKI and how serious it is. Care may involve:
- Stopping or changing medicines causing harm to your kidneys
- Dietary changes that limit how much protein you eat
- IV fluids
—a machine works for your kidneys by filtering your blood
- Caring for problems such as kidney stones or infections
—a machine used to filter waste from the blood
To lower your chances of AKI, don’t take medicines you know cause kidney problems. Your doctor will find other medicines to help you.
National Institute of Diabetes and Digestive and Kidney Diseases
National Kidney Foundation
The Kidney Foundation of Canada
Acute kidney injury. EBSCO DynaMed website. Available at:
Updated April 26, 2018. Accessed May 31, 2018.
Acute kidney injury (AKI). Merck Manual Professional Version website. Available at: https://www.merckmanuals.com/professional/genitourinary-disorders/acute-kidney-injury/acute-kidney-injury-aki. Updated December 2017. Accessed May 31, 2018.
Kidney failure. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/kidney-disease/kidney-failure. Accessed May 31, 2018.
Rahman M, Shad F, Smith MC. Acute kidney injury: a guide to diagnosis and management.
Am Fam Physician. 2012;86(7):631-639.
Last reviewed May 2018 by
EBSCO Medical Review Board
Adrienne Carmack, MD
Last Updated: 5/31/2018