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Acute Kidney Failure (AKF)


Acute kidney failure (AKF), also known as acute kidney injury (AKI), is a rapid decline in renal function manifested by a rise in serum creatinine or a reduction in urine output, or both, within seven days.

Kidneys are paired structures located near the back wall of your abdomen and side areas called flank, one on each side of the spine whose function is to filter the waste materials out of the blood and produce urine as a by-product. Once your kidneys reduce their filtering abilities, harmful levels of debris can build up, and the chemical makeup of your blood can become unbalanced. Those who have had AKI have a higher risk of having chronic renal disease later in life.

Acute renal failure is more prevalent among people who have already been admitted to a hospital, especially those who are seriously ill and require critical care. It is managed by the treatment of the root cause as well as a supportive therapy, such as renal replacement therapy.

Types And Causes

According to the cause, location, and mechanism, Acute kidney injury is typically divided into three categories: prerenal, intrinsic, and postrenal.

Prerenal: This category includes conditions that cause AKI by slowing blood flow to the kidneys. e.g.

  • Loss of blood or fluid
  • Burns or dehydration
  • Medication for high blood pressure
  • Cardiovascular illness
  • Failure of the liver
  • Taking aspirin, ibuprofen, naproxen sodium, or other similar medications
  • Anaphylaxis

Intrinsic causes: This category includes conditions that cause AKI by direct damage to the kidneys:

  • Hemolytic uremic syndrome, a disorder caused by the early death of red blood cells
  • Glomerulonephritis.
  • Hemolytic uremic syndrome (HUS), which is caused by the untimely destruction of RBCs
  • Infection, such as that caused by the coronavirus in 2019. (COVID-19)
  • Lupus, a glomerulonephritis-causing immune system illness
  • Medications: chemotherapeutic medications, antibiotics, and dye
  •  Scleroderma, a connective tissue disorder
  • Thrombosis in and around the kidneys' veins and arteries
  • Cholesterol plaques in the kidneys that obstruct blood flow
  •  Rhabdomyolysis; a muscle disease
  • Tumor lysis syndrome, which results in the production of chemicals that might harm the kidneys.
  • Thrombotic thrombocytopenic purpura
  • Toxins, e.g., alcohol, heavy metals, and cocaine

Postrenal causes: This category includes conditions that cause AKI by obstructing the passage of urine out of the body:

  • Renal stones
  • Blood clots
  • Nerve injury affecting the bladder's control
  • Prostate cancer or hypertrophy
  • Cancer of the bladder, cervix, or colon

Risk Factors And Epidemiology

Nearly 1 percent of patients hospitalized have AKI at the beginning of treatment. The overall incidence of AKI throughout hospitalization is 2-5 percent. AKI occurs in less than 30 days of surgery in about 1% of general surgery cases and above 50% of acute care setting (ICU) patients. AKI is the cause of about 95% of nephrology consultations. If you're above the age of 50 or have any of the following long-term health issues, you're more likely to develop acute kidney failure:

Signs And Symptoms

Signs and symptoms include:

  • Difficulty in breathing
  • Irregular heartbeat
  • Confusion
  • Headache and vomiting
  • Pain or pressure in the chest
  • Seizures
  • Lethargy, fatigue
  • Decreased appetite
  • Low urine output
  • Swelling in your lower limb due to fluid retention.
  • Potassium levels that rise dramatically can cause irregular cardiac rhythms.
  • Pain in the flanks

Acute renal failure can sometimes go unnoticed and only be identified through laboratory tests performed for another reason.


Clinical history and lab results are used to diagnose acute renal damage. There should be a sudden decrease in kidney function for kidney failure, as indicated by serum creatinine, or a quick decrease in urine production, known as oliguria (less than 400 MLS of urine per day).

Blood tests: CBC and Peripheral Smear,  Kidney functions tests (Kidney failure is defined by elevated blood urea nitrogen (BUN) and serum creatinine)

Urine tests: urine analysis and urinary electrolytes may detect changes that indicate renal failure. Your doctor may ask you to collect urine for 24 hours to look for decreased urine volume for Urine output assessment.

Imaging: Your clinician may be using imaging studies such as ultrasound of your kidneys and computed tomography to see your kidneys.

Biopsy: A sample of kidney tissue is removed for testing. Your doctor may suggest a renal biopsy to extract a sample of kidney tissue for examination in some cases.


The type of treatment you receive will be determined by the cause of your acute renal failure. The aim is to get your kidneys back to normal. An evaluation is usually performed by a kidney expert known as a "nephrologist.” Your diet and the number and amount of liquids you consume and drink will be restricted by your doctor. This will prevent toxins from accumulating in the kidneys. A high-carbohydrate, low-protein, low-salt, and low-potassium diet is commonly prescribed. The primary goals of AKI treatment are volume homeostasis and correction of metabolic abnormalities, and may involve the following measures:

Fluid therapy: Intravenous (IV) administration of isotonic sodium chloride solution is the only treatment or prophylactic intervention with a proven positive impact in AKI treatment. It should be administered in adequate doses to keep the patient euvolemic, if not hypervolemic.
Antibiotics: Your doctor may prescribe antibiotics to treat or prevent any concurrent infections.
Diuretics: Diuretics may aid in the removal of fluid from your kidneys. Furosemide is used to treat fluid excess. They appear to help maintain fluid balance and are widely utilized.

Inotropic Agents: Dopamine in small doses reduces absorption of sodium and enhances renal perfusion. 
Medications to decrease potassium levels: Calcium and insulin can help you prevent harmful potassium levels in your blood that could be dangerous for your heart.

Other medicines: Vasodilators such as Fenoldopam, Calcium Channel Blockers like Nefidipine, Antidotes such as N-acetylcysteine, Angiotensin converting enzyme (ACE) inhibitors, Atrial Natriuretic Peptide (ANP), specific hydration fluids, etc.

Dialysis: If toxins accumulate in the bloodstream, you may need temporary dialysis to eliminate them from your body while your kidneys heal. In dialysis, a machine pumps blood out of your body and filters it through a dialysis machine. After that, the blood is restored to your body. Dialysis is required if your mental state worsens or if you stop urinating. If you develop pericarditis, you may need dialysis. It can assist in the removal of nitrogen waste products from the body.


The prognosis for acute renal failure is dependent on the source of the illness. The prognosis is good if the reason is not caused by injury to the kidney tissue itself, and the individual will most likely recover completely. In cases where the damage does not entirely heal, the partial return of renal function may occur. The more unwell an individual is at the beginning of renal failure, the worse the prognosis.

Lifestyle Modifications

A healthy lifestyle should be your top priority. Be energetic, eat a healthy, nutritious diet, but only consume alcohol in moderation, if ever.
Stay focused with treatment plans and implement your doctor's instructions to manage your health if you have renal disease or another condition that raises your risk of acute kidney failures, like high blood pressure or diabetes.
Always ask your doctor if you need to take Aspirin, ibuprofen, and similar pain medications very often. Consuming too many of these medications can put your kidneys at risk, specifically if you have pre-existing kidney disease, diabetes, or high blood pressure.


Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available.

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