Acute kidney injury

Acute kidney injury

Acute cortical necrosis in the kidney

Diagram illustrating acute renal failure

Acute kidney injury (AKI), previously known as acute renal failure, is a sudden episode of kidney failure or kidney damage that happens within a few hours or a few days. It causes a build-up of waste products in the blood and makes it hard for the kidneys to maintain the right balance of fluid in the body.

Causes

AKI can be caused by a variety of factors, which are generally categorized into three main types:

Prerenal causes

Prerenal causes are due to decreased blood flow to the kidneys. This can occur due to severe dehydration, heart failure, or shock.

Intrinsic renal causes

Intrinsic renal causes are due to direct damage to the kidneys themselves. This can be due to inflammation, toxins, drugs, infection, or reduced blood supply.

Postrenal causes

Postrenal causes are due to obstruction of urine flow. This can occur due to kidney stones, tumors, or an enlarged prostate.

Symptoms

The symptoms of AKI can vary depending on the underlying cause and severity. Common symptoms include:

• Decreased urine output
• Swelling due to fluid retention
• Fatigue
• Shortness of breath
• Confusion
• Nausea

Diagnosis

Diagnosis of AKI is based on laboratory tests and imaging studies. Key diagnostic tests include:

• Blood urea nitrogen (BUN) and creatinine levels
• Urinalysis
• Ultrasonography

Ultrasonography of acute pyelonephritis

Ultrasonography of postoperative renal failure

Treatment

Treatment of AKI focuses on addressing the underlying cause and supporting kidney function. This may include:

• Fluid management
• Medications to control blood pressure
• Dialysis in severe cases

Prognosis

The prognosis of AKI depends on the underlying cause and the promptness of treatment. Some patients recover completely, while others may develop chronic kidney disease.

Prevention

Preventive measures include:

• Adequate hydration
• Monitoring and managing chronic conditions such as diabetes and hypertension
• Avoiding nephrotoxic drugs when possible

Related pages

• Chronic kidney disease
• Dialysis
• Nephrology
• Renal physiology

Gallery

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  Ultrasonography of renal trauma with laceration

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  Acute cortical necrosis
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  Acute renal failure diagram
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  Ultrasonography of acute pyelonephritis
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  Ultrasonography of postoperative renal failure
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  Ultrasonography of renal trauma with laceration