Kidneys: What are they?

The kidneys are a pair of bean - shaped organs located at the back of the body about the level of the waist. Each kidney measures 10-15 cm in length and weighs approximately 160 grams. There is a constant flow of blood through the kidneys. Inside the kidneys, the blood is filtered, through millions of small, thinly walled blood vessels. The fluid filtered out is called urine. The urine is collected in the central part of the kidney and passes through the urinary ducts, or urethras, down to the bladder. Each day the two kidneys excrete about 1-2 litres of urine.


The function of the Kidneys

The kidneys perform the vital jobs of cleaning the blood of waste products and removing excess fluid. They filter the blood. The other functions of the kidney are to maintain the body's balance of various salts such as sodium, potassium, calcium, phosphate as well as acid. They release hormones, which influence the bone structure (Vit D), the generation of red blood cells (erythropoietin) and the regulation of blood pressure.


Kidney Failure

Kidney failure occurs when the kidneys stop working or the level of efficiency is less than 10%. When the kidney function deteriorates, the waste products and excess fluid remain in the body. These waste products and fluids are toxic in large quantities, and their accumulation will eventually lead to nausea, headaches, and dizziness. Your skin may begin to itch, and various parts of your body may swell as a result of fluid retention. This retention of fluid called oedema will lead to an increase in body weight, resulting in high blood pressure and respiratory problems.


Kidney failure can lead to blood deficiency (anaemia) and brittle bones.


Acute renal failure occurs when the kidneys suddenly stop working. This condition is temporary. The cause may be disease, injury, major surgery or toxic agents. Chronic renal failure can occur suddenly, or develop gradually over a period of time. This is not reversible. Kidney function never returns.


Causes of Kidney Failure

The common causes of kidney failure are hypertension and diabetes mellitus. Other causes include glomerulonephritis (inflammation of the kidney), blockage, chronic infection, hereditary, accidents and injury caused by medication, drugs, poisons, and radiation. Kidney failure is life threatening unless treated by dialysis or transplantation.


Symptoms of Kidney Failure

Uraemia is the medical term to describe symptoms when the kidneys no longer work. When waste products build up in the blood stream, you may feel sick due to the symptoms of uraemia.


Symptoms include the following:

A headache, drowsiness, nausea, vomiting, itching, feeling tired, high blood pressure, diarrhoea, decrease in urination, swelling, loss of appetite and thirst.