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Understanding Kidney Disease: Information, Symptoms, Treatment, and Prevention
The Basics | Symptoms | Treatment | Prevention
The Basics
The kidneys, two fist-sized organs located on either side of your spine just above the waist, perform several life-sustaining roles. They cleanse your blood by removing waste and excess fluids, maintain the balance of salt and minerals in your blood, and help regulate blood pressure.
When the kidneys become damaged, waste products and fluid can build up in the body, causing a swelling in your hands and feet, shortness of breath, and frequent urge to urinate. If left untreated, diseased kidneys may eventually stop functioning completely. Loss of kidney function is a serious -- potentially fatal -- condition.
Each bean-shaped kidney is 4 to 5 inches long and contains about a million nephrons, which are like tiny pouches. Each nephron has a filter at one end, called a glomerulus, to filter your blood. Your overall kidney function can be measured by how quickly blood is filtered through these glomeruli. This measurement is called the glomerular filtration rate.
Healthy kidneys handle several specific roles:
- Maintain your body's balance of water and concentration of minerals such as sodium, potassium, magnesium, and phosphorus in your blood.
- Remove waste by-products from the blood after digestion, muscle activity, and exposure to chemicals or medications.
- Produce renin, an enzyme that helps regulate blood pressure.
- Produce erythropoietin, which stimulates red blood cell production.
- Produce an active form of vitamin D, needed for bone health.
What Causes Acute Kidney Failure?
The loss of kidney function over several hours or days is called acute kidney failure, also known as acute renal failure (ARF). Kidney failure can occur following a traumatic injury with blood loss, the onset of a medical condition that suddenly reduces blood flow to the kidneys, or damage to the kidneys from shock during a severe infection called sepsis.
Acute kidney failure can also happen during a pregnancy complication, such as eclampsia, pre-eclampsia, or HELLP Syndrome (a blood and liver disorder occurring near delivery).
Inhaling or swallowing certain toxins can also cause the kidneys to slow or stop functioning suddenly. These toxins include methyl (wood) alcohol, carbon tetrachloride, ethylene glycol in antifreeze, and poisonous mushrooms.
Marathon runners and other athletes who don't drink enough fluids while competing in long-distance endurance events may suffer acute kidney failure due to a sudden breakdown of muscle tissue. This muscle breakdown releases a chemical called myoglobin that can damage the kidneys.
Infection with streptococcal bacteria can also result in acute kidney failure. Certain medications or medical treatments may have unpredictable effects on the kidneys and can cause a sudden decrease in kidney function.
What CausesChronic Kidney Disease?
Kidney damage and decreased function lasting longer than 3 months is called chronic kidney disease (CKD). Chronic kidney disease is particularly dangerous since you may not have any symptoms until considerable, often irreparable, kidney damage has been done.
Diabetes and high blood pressure are the most common causes of chronic kidney disease (CKD).
Diabetes, both type 1 and type 2 diabetes, can damage and scar the kidneys, with a loss of kidney function that's often progressive over time. Medical care can slow, but not reverse, this kidney damage. Diabetes is a leading reason why people need dialysis or a kidney transplant.
High blood pressure(hypertension) contributes to a loss of kidney function, generally over years. Hypertension can damage the blood vessels in your kidneys and accelerate kidney damage from other causes, such as diabetes, as well. The combination of high blood pressure and excess protein in the urine raises the risk of developing heart disease and stroke.
Immune system conditions, such as lupus, and chronic viral illnesses such as HIV/AIDS, hepatitis B, and hepatitis C can cause kidney damage.
A severe infection within the kidneys themselves, called pyelonephritis, can lead to scarring as the infection heals. Multiple episodes can lead to kidney damage.
Inflammation in the tiny filters (glomeruli) within the kidneys is called glomerulonephritis. This can happen suddenly, such as after an infection with certain strains of bacteria called streptococci. Chronic, long-term inflammation can cause progressive kidney damage and loss of function.
Polycystic kidney disease is the most common form of inherited kidney disease. With this condition, fluid-filled cysts form in the kidneys over time, which can damage the kidneys and cause kidney failure.
Congenital defects, which are present at birth, are often the result of a urinary tract obstruction or malformation that affects the kidneys. One of the most common involves a valve-like mechanism between the bladder and urethra. These defects, sometimes found while a baby is still in the womb, can often be surgically repaired by a urologist.
Drugs and toxins, includinglong-term exposure to some medications and chemicals, can damage the kidneys. Overuse of NSAIDS (nonsteroidal anti-inflammatory drugs) such as ibuprofen and naproxen can be harmful to the kidneys in some people. Intravenous €śstreet €ť drugs can cause kidney disease. Researchers suspect that excessive amounts of vitamin D and protein, particularly for elderly or extremely ill people, may harm the kidneys.
The Basics | Symptoms | Treatment | Prevention
