Definition

Acute kidney injury (AKI) is the sudden loss of kidney function. Kidneys clean waste products 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
Glomerulonephritis
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Causes

AKI has many causes:

  • Blood is blocked from going into the kidneys because of:
  • Problems inside the kidney cause loss of filter because of:
    • Problems after surgery
    • Inflammation
    • Blood clots
    • Medicine side effects
  • Kidney stones
  • Enlarged prostate

Risk Factors

AKI is most common in older adults. Your chances are also higher if you have:

  • Diabetes
  • High blood pressure
  • Kidney, liver, or heart disease
  • Dehydration
  • 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)
  • Some blood pressure or heart medicine when dehydration is also present
  • Blockages, which can happen with benign prostatic hyperplasia or a bladder tumor

Symptoms

Most people do not have symptoms. In those that have them, AKI may cause:

  • Lower or higher amounts of urine than normal
  • Dark or red urine
  • Fatigue
  • Confusion
  • Nausea or vomiting
  • Muscle weakness
  • Muscle cramps
  • Lack of hunger
  • Swelling
  • Weight gain

Diagnosis

The doctor will ask about your symptoms and health history. You may also have:

Treatment

Care depends on the cause of AKI and how serious it is. Care may involve:

  • Stopping or changing medicines causing harm to your kidneys
  • Controlling blood pressure and diabetes
  • Avoiding medicine that could be harmful such as NSAIDs common in over-the-counter pain medicine
  • Dietary changes that may limit how much salt and protein you eat
  • IV fluids
  • Dialysis —a machine works for your kidneys by filtering your blood
  • Caring for problems such as kidney stones or infections

Prevention

Most AKI can not be prevented.

Revision Information

  • Reviewer: EBSCO Medical Review Board Adrienne Carmack, MD
  • Review Date: 09/2019 -
  • Update Date: 09/13/2019 -