Skip to main content
Oxford University Hospitals NHS Foundation Trust
Oxford Kidney Unit

This site is best viewed with a modern browser. You appear to be using an old version of Internet Explorer.

Kidney disease

What do the kidneys do?

The kidneys:

  • remove waste products and excess water (excess salt and water leads to swelling, high blood pressure, and can cause fluid to build up in the lungs)
  • make a hormone called erythropoietin (or EPO) which instructs the body to make blood to prevent anaemia; anaemia causes tiredness and other symptoms
  • help to control blood pressure (high blood pressure can increase the chance of developing heart disease or suffering a stroke)
  • activate vitamin D (from sunlight or diet); active vitamin D is needed for healthy bones.

What is kidney failure?

Damage can occur to kidneys filtering units because of the following.

  • Diabetes
  • Hypertension (high blood pressure)
  • Glomerulonephritis (inflammation and damage to the kidneys filtering units)
  • Inherited diseases (for example - polycystic kidney disease)
  • Diseases that affect the immune system (for example - lupus)
  • Obstructions (kidney stones, enlarged prostate in men)

This can lead to Chronic Kidney Disease (CKD) commonly called 'kidney failure'. CKD is the
term used to describe how severe the kidney failure is. There are 5 Stages and although
chronic means a condition that does not get completely better, it does not always mean
that your kidney failure is severe or that it will progress through all of the stages to stage 5.

What stage is my kidney failure?

Estimated Glomerular Filtration Rate (eGFR) is one of the blood tests used to measure your kidney function. It is sometimes referred to as a percentage of normal kidney function.

If your kidneys are not filtering well, your eGFR falls. By comparing the results with previous tests, we can see whether your kidneys are still working at the same rate as before.

This helps us to work out which stage your kidney failure is at. If kidney failure progresses to stage 5 it can be managed with dialysis, and/or a transplant, or conservative management.

Healthy kidneys are very efficient. They do not have to work at full strength to do their job properly - in fact; one kidney is quite capable of doing all the work. This is why healthy people can donate one of their kidneys to another person.

Common symptoms

As kidney function falls you may begin to experience some symptoms.

The symptoms are usually due to the build up of waste products in your blood as your kidneys are not able to filter or 'clean up' efficiently. Some of the symptoms can also be due to anaemia. These symptoms are sometimes referred to as 'uraemia'.

As well as monitoring your kidney function by taking blood tests, we will be asking you about any symptoms that you might be experiencing.

Together these results will help us to determine your treatment plan.

Symptoms of uraemia may include:

  • tiredness
  • trouble concentrating
  • loss of appetite and weight loss
  • nausea and vomiting
  • itching
  • decreased sexual interest / performance
  • trouble sleeping
  • shortness of breath
  • high blood pressure
  • swollen ankles, puffiness around the eye.

You may not experience all of these symptoms and they may be related to other problems.

Please make a note if you want to discuss them.