Kidney Failure (Renal Failure)

Definition

Kidney failure occurs when one or both kidneys are not able to perform their usual functions. The kidneys are two bean-shaped organs in the lower back. Their main function is to remove waste from the body and to balance the water and electrolyte content of the blood by filtering the salt and water in the blood. The waste and water excreted by the kidneys combine to form urine.

Kidney failure is divided into acute and chronic.

• Acute kidney failure —sudden loss of kidney function
• Chronic kidney failure —slow, gradual loss of kidney function

If kidney function is reduced to 20% of normal function, serious health problems develop. When kidney function decreases to 10%-15% of normal, dialysis or a transplant is needed to maintain life.

Causes

Kidney diseases cause the tiny filters in the kidneys (called nephrons) to lose their filtering ability. Damage to the nephrons may occur suddenly after an injury or poisoning. However, many kidney diseases take years or even decades to cause damage that is noticeable.

The two most commons causes of kidney failure are:

• Diabetes —Longstanding high blood sugar that results from diabetes damages the nephrons.
• High blood pressure —Longstanding, severe high blood pressure damages the capillaries in the kidneys

Others causes of kidney failure may include:

• Pyelonephritis
• Glomerulonephritis
• Polycystic kidney disease
• Birth defects
• Bilateral renal artery stenosis
• Poisoning
• Severe trauma
• Viral infections: hepatitis B , hepatitis C , HIV/AIDS
• Long-term use of medicines that contain:
  
  • Aspirin
  • Acetaminophen
  • Ibuprofen
• Abnormal build-up of substances within the kidneys, such as:
  
  • Amyloidosis
  • Protein build-up
• Toxic reaction to drugs or x-ray dyes
• Systemic diseases, including:
  
  • Systemic lupus erythematosus (lupus)
  • Polyarteritis
  • Wegener's and Goodpasture's granulomatosis
• Conditions that severely decrease circulating fluid/blood volume, such as:
  
  • Severe blood loss
  • Burns
  • Pancreatitis
  • Peritonitis
  • Sepsis
  • Heart failure
  • Liver disease
  • Shock (due to any of the above conditions or a sudden and severe drop in blood pressure)
• Conditions that causes obstruction of the flow of urine, such as:
  
  • Enlarged Prostate
  • Large kidney stones
  • Abdominal tumors blocking the ureters

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors for kidney failure include:

• Diabetes
• Genetics: polycystic kidney disease, type 1 diabetes
• Race: African Americans
• High blood pressure
• Lupus or other inflammatory/auto-immune diseases
• Long-term use of painkillers containing aspirin or NSAIDs in high doses
• Liver failure, jaundice
• Respiratory failure
• HIV
• Cancer
• Recent open heart surgery
• Recent surgery on an abdominal aortic aneurysm
• Condition that obstructs urine flow
• Enlargement of the prostate gland

Symptoms

Some kidney diseases begin without any symptoms at all. As kidney failure progresses, some of the following symptoms may develop:

• Fluid retention
• Swollen hands and feet
• Numbness of hands and feet
• Itchy skin
• Fatigue
• Low urine output
• Frequent urination
• Insomnia
• Altered consciousness
• Loss of appetite, malnutrition
• Sores, bad taste in the mouth
• Nausea
• Vomiting
• Muscle cramps and twitches
• Shortness of breath
• Pericarditis
• Swelling throughout the body
• High blood pressure
• Low temperature
• Seizures
• Coma
• Breath smelling like urine (uremic fetor)
• Yellowish-brownish skin tone

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam.

Tests may include:

Treatment

Most chronic kidney diseases are not reversible, but the following are treatments that may be recommended to help preserve as much kidney function as possible. These treatments will also be use to try to reverse some of the ill effects of kidney failure.

In the cases of acute renal failure treatment is targeted to the illness or injury causing the problem and try to reverse it.

Prevention

In some cases, you cannot prevent kidney failure. But there are some steps you can take that will lower your risk of kidney failure:

• Maintain normal blood pressure.
• If you are diabetic, control your blood sugar.
• Avoid long-term exposure to toxic substances such as lead and solvents.
• Do not abuse alcohol or over-the-counter pain medication.
• Limit the amount of drugs toxic to the kidney.
• If you have chronic kidney failure, consult your doctor before you become pregnant.