Kidney Failure (Renal Failure)
What is it?
The kidneys are responsible for getting rid of the body's waste products. If the kidneys stop working properly (known as kidney or renal failure), waste products can build up in the blood and body. If the levels of waste products are quite mild, there may be few or no symptoms. But if renal failure continues, then symptoms will begin to appear.
Renal failure can either happen very quickly, over a few days, weeks or months (known as acute renal failure) or slowly over a period of years (chronic renal failure).
Acute renal failure
This can result from any serious illness or operation, especially if there has been a severe infection. Kidneys can become damaged if the blood supply to them is reduced, for example, through blood loss, fall in blood pressure or severe dehydration. If the problem lasts long enough, the kidneys can become permanently damaged. Other reasons for acute renal failure are a blockage in the ureter (the tube from the kidney to the bladder) or as a side effect of some medications.
Chronic renal failure
Chronic renal failure can result from any disease that causes a gradual loss of kidney function. Diabetes and hypertension (high blood pressure) are the two most common causes and account for approximately two thirds of chronic renal failure cases. Other major causes include glomerulonephritis of any type (one of the most common causes), polycystic kidney disease, ongoing blockage of the ureter, kidney stones, infection, and kidney damage from long-term painkiller use. Often the initial cause of the kidney failure occurred some time ago, and cannot be identified. Chronic renal failure gets slowly worse and can become severe and even life-threatening.
What are the symptoms?
The symptoms of acute renal failure and chronic renal failure are different.
Acute renal failure
The symptoms of acute renal failure are usually the symptoms of the condition causing the failure, for example:
Chronic renal failure
In the case of chronic renal failure, the problem is usually not identified at an early stage, and so has been going on for some time. It is often discovered at routine examinations of the blood and urine. Symptoms may not be noticed until the kidney failure is very advanced.
Symptoms include:
How is it diagnosed?
The doctor will diagnose renal failure based on your symptoms, a physical examination and tests of your blood and urine, which will show whether your kidneys are working normally.
Further tests may include:
Ultrasound
Ultrasound is when sound waves are used to project an image of the inside of your abdomen onto a computer screen.
Computerised tomography
Computerised tomography, also known as a CT scan, takes x-rays of the body from different angles to make a detailed, cross-sectional image. Sometimes a dye is injected to make the images more detailed.
Magnetic resonance imaging
Magnetic resonance imaging, also known as MRI, uses magnetic fields instead of x-rays to produce images.
How is it treated?
Acute renal failure
The main aim of treating acute renal failure is to identify and treat the underlying cause of the renal failure.
You may also be given medication that controls your blood potassium levels, antibiotics to treat or prevent infection, diuretics (water pills) that encourage the kidney to remove fluid, and you may be put on a special diet to reduce the amount of toxins in your blood, to make your kidneys' job a little easier. If the ureters (tubes from your kidneys) are blocked, fine internal tubes called stents can be put in place to relieve the obstruction.
If the renal failure is life-threatening, you may need to go onto a dialysis machine (an artificial mechanical kidney that ‘cleans' your blood) for a short while until kidney function has returned to normal. The process of dialysis removes waste products from the blood and removes excess water.
Chronic renal failure
As long-term damage to the kidneys is irreversible, there is no cure for chronic renal failure. Treatment focuses on controlling symptoms and slowing down the progression of the disease. Other conditions that can follow-on from chronic renal failure must be controlled and treated where possible. These conditions include high blood pressure, heart failure, urinary tract infections, and kidney stones. If you become anaemic, blood transfusions or iron medications might be necessary. Your diet will probably be adjusted to make sure that less waste is produced so that your kidneys do not have to work so hard.
If your kidneys continue to deteriorate in function, you may develop end-stage renal disease. End stage renal failure usually follows after 10 to 20 years of chronic renal failure.
End stage renal disease
End stage renal disease (ESRD) is when the kidneys are so damaged that they are no longer able to work effectively enough to support day-to-day life. This is usually when the kidneys are working at 10% of their capacity. At this stage, without long-term dialysis or kidney transplantation, severe complications and death will occur from the accumulation of fluids, toxins and poisons in the body. Dialysis or a kidney transplant are the ONLY methods of treatment for someone with ESRD.
Further information
Your local GP surgery is the best place for you to find information on renal failure, especially if you have specific concerns about your symptoms and treatment. Charities related to the kidney can also be useful sources of information and support.
Kidneywise www.kidneywise.com
UK National Kidney Foundation www.kidney.org.uk
