We use cookies on this website. See how you can control your settings.

About us | Sitemap | Links | Accessibility | Copyright | Contact us | News | Video | Kidneypedia | Kidney disease | Kidney treatment | Patient lifestyle | Research |

The A-Z gives the correct definitions of words you will often come across as a kidney patient. The medicines guide describes some of the medication you may be prescribed.

The definitive guide to kidneys and your health

The A-Z of kidneys


Nurse with patient connected to a dialysis machine.

The machine helps pump blood through the dialyser, which filters it before returning it to your body.

This glossary provides brief explanations of the various technical words and abbreviations used by healthcare professionals when talking about kidneys, chronic kidney disease (CKD) and its treatment.


A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

The lower part of your trunk, below your chest, sometimes called the tummy or belly.

A word meaning "short-term" and starting rapidly. It usually requires a rapid response.

A method of gaining entry to the inside of your body to allow dialysis. In peritoneal dialysis access refers to the catheter (tube) entering your abdomen. In haemodialysis it refers to the fistula or dialysis line.

A shortage of red blood cells in the body. This causes tiredness, shortness of breath, loss of appetite and pale skin. One of the functions of the kidneys is to make EPO (erythropoietin). This stimulates your bone marrow to make blood cells. With kidney disease, your kidneys do not make EPO and you become anaemic.

Substances that normally help your body fight infection. They are made by white blood cells. After a transplant, antibodies can attack the new kidney and cause rejection. Antibodies also cause some kidney diseases such as glomerulonephritis.

An abbreviation for Automated Peritoneal Dialysis. This type of peritoneal dialysis uses a machine to drain the dialysis fluid out of you and then replaces it with fresh solution. APD is usually done overnight.

Blood vessels that carry blood from your heart to the rest of your body.

A kidney (renal) biopsy is a medical test. It can identify the cause of your kidney problem. A tiny piece of tissue is removed from your kidney with a special needle and examined under a microscope.

The organ where your urine is stored before being passed from your body.

Blood cells
The microscopically tiny units that form the solid part of your blood. There are three main types: red blood cells, white blood cells, and platelets.

Blood group
An inherited characteristic of red blood cells. The common classification is based on whether or not you have certain antigens (called A and B) on your cells. People belong to one of four blood groups, called A, B, AB and O.

Blood pressure (BP)
This is the pressure that your blood exerts against the walls of your arteries as it flows through them. One of the functions of your kidneys is to help control your blood pressure.

Blood vessels
The tubes that carry blood around your body. The main blood vessels are the arteries and the veins.

Body mass index (BMI)
This is a measure of your weight relative to your height. It is associated with your body fat and health risk. A healthy body BMI is between 20-25 kg/m2. If your BMI is more than 25 you are at risk of health problems. If your BMI is more than 30 you might have more complications during the transplant operation and you will tend to heal less well. You can work out your BMI on the NHS Choices website.

The abbreviation for Continuous Ambulatory Peritoneal Dialysis. This is a continuous form of peritoneal dialysis. You carry out the exchanges of dialysis fluid by hand. The fluid is usually exchanged four times during the day.

This is a flexible plastic tube used to enter the interior of your body. If you are having peritoneal dialysis, a PD catheter allows dialysis fluid to be put into and removed from your peritoneal cavity.

Long-term and of slow onset.

Conservative management
Treatment of  kidney failure without the use of dialysis or a transplant.

Diabetes mellitus
A condition in which there is too much sugar in your blood.  Diabetes can cause kidney disease; this happens most often to people who have had diabetes for longer than ten years.

Artificial kidney

An artificial process to remove the toxic waste products of food and excess water from your body. Dialysis therefore takes over some of the work normally carried out by healthy kidneys.

Dialysis machine
This is the machine used to carry out haemodialysis. It includes a dialyser, which filters your blood. The machine helps to pump your blood through the dialyser, and monitors the dialysis process as it takes place.

Abbreviation for erythropoeitin. See below.

A hormone made by your kidneys. It stimulates your bone marrow to produce red blood cells. It can be given by injection.

An enlarged blood vessel that gives access to the bloodstream for haemodialysis. It is usually at the wrist or elbow. A surgeon creates a fistula by joining an artery to a vein in a small operation. This increases the flow of blood through the vein and causes it to enlarge, making it suitable for haemodialysis needles.

A general term meaning inflamed and damaged kidneys.

A form of dialysis in which your blood is cleaned outside your body, via a machine called a dialysis machine or kidney machine.

An infection of the liver. It is usually caused by a virus. The two main types are hepatitis B and hepatitis C. They can be passed on by blood contact.

High blood pressure

Live donor transplant
A term for a transplant where the donor is living and either unrelated or related to the recipient.

A general term for inflammation of the kidneys. Also used as an abbreviation for glomerulonephritis (GN).

Study of the kidneys.

Peritoneal Dialysis (PD) catheter
A plastic tube through which dialysis fluid for peritoneal dialysis is put into, and removed from, your peritoneal cavity.

Peritoneal cavity
The area inside your abdomen. The peritoneal cavity contains your abdominal organs, including your stomach, liver and bowels. It normally contains only about 100ml of liquid, but expands easily to provide a reservoir for the dialysis fluid in peritoneal dialysis.

Peritoneal dialysis (PD)
A type of dialysis that takes place inside your peritoneal cavity. It uses the peritoneum as the dialysis membrane. Bags of dialysis fluid, containing glucose (sugar) and various other substances, are drained in and out of the peritoneal cavity via a PD catheter.

A natural membrane that lines the inside of the wall of your abdomen and covers all your abdominal organs (the stomach, bowels, liver, etc.). Your peritoneum provides the dialysis membrane for peritoneal dialysis. It has a large surface area, contains many tiny holes and has a good blood supply.

The inflammation of your peritoneum. It is caused by an infection.

A mineral that helps calcium to strengthen your bones.

Polycystic kidney disease (PKD)
A disease in which both kidneys are full of cysts (abnormal lumps). It is inherited (runs in families).

A body 'salt ' which is needed to help your muscles work properly, in particular your heart muscles.

Red blood cells
The cells in your blood which carry oxygen from your lungs around your body.

The process by which your immune system recognises a transplanted kidney (or other transplanted organ) as not its 'own' and then tries to destroy it.

Means relating to the kidneys.

Renal bone disease
A complication of kidney disease. Abnormally low blood levels of calcium and vitamin D and high levels of phosphate affect the health of your bones. Without treatment, it can result in bone pain and fractures.

Renovascular disease
A common cause of kidney disease in older people; fatty deposits affect the blood vessels that supply your kidneys.

Satellite haemodialysis unit
A place where you can go for haemodialysis away from the main hospital renal unit.

Supportive care
Treatment of kidney failure without the use of dialysis or transplant.

Toxins (poisons)
One of the main functions of your kidneys is to remove toxins from your blood. This process is known as clearance.

Transplant pool (sometimes called the transplant waiting list)
A system that tries to find the 'right' transplant organ for the 'right' patient. It is coordinated nationally in the UK by NHS Blood and Transplant . Their computer compares patients' details (including blood group and tissue type) with those of deceased donor organs that become available.

Ultrasound scan
This is a procedure that creates an image of an organ in the body.

A substance made by your liver. It is one of the waste products from food that builds up in your blood if you have kidney disease. The higher the urea level, the worse the kidney disease.

The tubes that take urine from your kidneys to your bladder.

The body's tube that takes urine from your bladder out of your body.

The liquid made by your kidneys. It is made up of the toxic waste products of food and the excess water from your blood.

Blood vessels which carry blood from your body back to your heart.

Vitamin D
A chemical that helps your body to absorb calcium from your diet. If you have kidney disease, the level of vitamin D in your blood is usually low.