What is the cause of kidney failure?

The most common causes of kidney disease are diabetes and hypertension (high blood pressure). Studies have shown that diabetes causes around half of all cases of kidney failure, and high pressure causes just over a quarter of cases.
　　Diabetes
　　Diabetes is a condition where the body does not produce enough insulin (type 1 diabetes) or does not make effective use of it (type 2 diabetes). Our bodies need insulin because it breaks down the glucose (sugar) in our blood in order to produce carbohydrate which provides us with energy.
　　If your diabetes is not well controlled, too much glucose (sugar) can build up in your blood. The glucose can then damage the nephrons (tiny filters), which in turn, affects the abilities of your kidneys to filter out waste products and fluids.
　　Type 1 diabetes is more likely to lead to kidney disease. It is estimated that between 20-40% of people with type 1 diabetes will develop kidney disease by the age of 50.
　　Kidney disease rarely occurs in the first 10 years of diabetes, and usually between 15-25 years will pass before kidney disease occurs. However, as treatment methods for diabetes improve, and diabetes can be better controlled, the number of people with diabetes who develop kidney disease is gradually falling.
　　Hypertension
　　Blood pressure is a measurement of how much pressure is required by your heart to pump the blood around your veins and arteries. Too much pressure can result in damage to your body's organs, and can lead to heart disease.
　　The causes of 90% of cases of high blood pressure (hypertension) are unknown, but there appears to be a link between the condition and general health, diet and lifestyle
　　Hypertension causes damage by putting strain on the small blood vessels in the kidneys. This prevents the filtering process from working properly.
　　Other causes of kidney disease include:
　　•glomerulonephritis (inflammation of the kidney),
　　•pyelonephritis (infection in the kidney),
　　•polycystic kidney disease (an inherited condition in which both kidneys are several times the normal size due to the gradual growth of masses of cysts),
　　•failure of normal kidney development in an unborn baby while developing in the womb,
　　•systemic lupus erythematosus (disease of the immune system where the body attacks the kidney as though it were foreign tissue),
　　•malaria and yellow fever (tropical diseases spread by mosquitoes) ,
　　•jaundice (a yellowing of the skin),
　　•overuse of medicines, such as nonsteroid anti-inflammatory medicines (NSAIDs), the most well known of which are aspirin and ibuprofen, as well as illegal drugs, such as heroin and cocaine,
　　•prolonged exposure to fuels, solvents and lead,
　　•blockages - for example, due to kidney stones, and
　　•a sharp blow or physical injury, to the kidney.
　　If you have a chronic condition that can cause kidney disease, such as diabetes, it is important that you carefully manage your condition. Follow all the advice given to you by your GP and keep all appointments relating to your condition. People with diabetes are recommended to have their kidney function tested every year.
　　Diet
　　Diet plays an important role in preventing kidney disease. A healthy diet will lower your levels of cholesterol and keep your blood pressure at a healthy level. You should eat a balanced diet, including plenty of fresh fruit and vegetables (five portions a day) and whole grains.
　　Exercise

　　Regular exercise can help lower blood pressure and it can also help to prevent other chronic conditions, such as diabetes and heart disease. Thirty minutes of moderate exercise a day, at least five times a week, is recommended. The exercise should be vigorous enough that it leaves your heart beating faster and you should feel slightly out of breath. Examples of moderate exercise are going for a brisk walk, or walking up a hill.