Acute Kidney Failure

What is Acute Kidney Failure?

Acute kidney failure (acute renal failure) can occur in a matter of weeks or just days. The kidneys become unable to filter metabolic waste from the blood steam. Both kidneys must be affected for acute renal failure to occur. It is most common in older and younger individuals. Blood tests and urine tests must be administered to confirm the diagnosis. The cause may be determined through a physical exam, an ultrasound, a CT scan and/or an MRI.

Major causes include

Obstruction of Urine Flow

  • Kidney stones
  • Enlarged prostate
  • Prostate, bladder, cervical or colon cancer
  • Bladder nerve damage
  • Urinary tract blood clots

Kidney injury

  • Prolonged decrease of blood supply to the kidneys
  • Infection
  • Toxins from certain medications, heavy metals, alcohol and illegal drug use
  • Disorder(s) that affect the filtering mechanism
  • Cholesterol build-up that blocks blood flow
  • Thrombotic thrombocytopenia purpura
  • Hemolytic uremic syndrome
  • Lupus
  • Plasma cell cancer
  • Scleroderma
  • Blood vessel inflammation (vasculitis)

Inadequate blood flow to the kidneys

  • Blood loss
  • Excessive sodium and fluid loss
  • Injury that blocks blood supply
  • Shock (severely low blood pressure)
  • Liver failure

What are the Symptoms of Acute Kidney Failure?

The symptoms of acute kidney failure depend on the severity of the condition, the cause and the speed of progression. Water retention is often the first obvious sign. The face, feet, ankles and hands become increasingly puffy. Urine output often decreases to less than 16 ounces per day or stops entirely, but not always.

Other symptoms may include

  • Nausea
  • Fatigue
  • Breathing problems
  • Itchiness
  • Very dark urine
  • Additional symptoms of the causes of acute renal failure

Acute Kidney Failure Causes

Acute kidney failure is the sudden loss of the function of the kidneys. It is characterized by the inability to eliminate toxins from the body and lack of urination. The causes of kidney failure can be diverse. Some persons with acute kidney failure suffer from infections. Bacterial and viral infections of the stomach are often known to cause acute kidney failure. Bites from certain animals, such as brown recluse spiders, may also cause renal failure in those who are susceptible.

While infections are a common reason for acute kidney failure, trauma may also be a cause. Penetrative trauma – injuries causes by objects such as knives or bullets – can damage the kidneys in ways that prevent important functions such as urination. In many cases, the cause of the injury is as simple as a punch. The blunt trauma of a punch to the lower back, where the kidneys rest, can be so severe it stops them from functioning all together. At least one-third of all acute kidney failure cases occur this way.

How is Acute Kidney Failure Treated?

The treatment of acute kidney failure begins with the remediation of the underlying cause, if the condition is treatable.

Kidneys can naturally heal

The kidneys can naturally heal if complications do not occur and renal failure has been fewer than five days. Certain drugs may be limited or completely eliminated. Potassium and salt will usually be restricted, and medication will be administered when phosphorus or potassium levels are elevated. Moderate protein consumption is permitted, but the intake of all substances that are removed via the kidneys are stringently restricted with a blockage.

Chronic kidney failure

Removal of metabolic waste products in the blood may be necessary through dialysis until the kidneys recover. When the kidneys cannot recover and properly filter metabolic waste, acute renal failure becomes chronic kidney failure.

Acute Kidney Failure Prevention

Prevention of acute kidney failure is well understood by doctors. The most important things anyone can do to prevent acute kidney failure is to drink lots of fluids and avoid foods that are taxing on the kidneys such as meats. Although genetics plays an important role in acute kidney failure, it’s clear that diet is incredibly important as well. The best foods for the kidneys are those that promote the filtration of waste, such as cranberry juice and leafy greens. Vitamin D and vitamin A levels are strongly linked to kidney health as well. Persons with acute kidney failure tend to have low levels of both. Caution when using medication is also an important goal in preventing acute kidney failure. Many drugs prescribed for pain and for chronic health conditions have the potential to damage the kidneys.

Last Reviewed:
September 11, 2016
Last Updated:
November 01, 2017