Simple explanations of some medical terms relating to kidney disease. 
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A

Abdomen:  The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder and other organs. 
 
Acid:  A water soluble, sour tasting chemical with a pH less than 7.
 
Acute Kidney (Renal) Failure:  A sudden drop in kidney function that is often short-lived and seldom means staying on dialysis.
 
Adequacy:  Refers to how well your dialysis is working. It measures the amount of waste removed from your blood and determines the amount of dialysis needed.

Albumin:  One of a simple group of water soluble blood proteins. In the blood, albumin acts as a carrier and helps to maintain blood volume and blood pressure. A blood test for albumin helps to determine if a patient has kidney disease or if the body is not absorbing enough protein.
 
Alkaline:  A substance that neutralises an acid and has a pH more than 7.

Alport's syndrome:  An inherited condition that results in kidney disease. Alport's syndrome usually develops during early childhood. The condition can lead to kidney failure and to hearing and vision problems. Common symptoms include blood and protein in the urine.

Amyloidosis:  A condition in which a protein-like material builds up in one or more organs. This material cannot be broken down and interferes with the normal function of that organ. People who have been on dialysis for several years often develop amyloidosis because the artificial membranes used in dialysis fail to filter the protein-like material out of the blood.
 
Amino acids:  Substances that make up proteins.
 
Anaemia:  When there are only a small number of red blood cells in the blood or the blood cells are not working properly. Red blood cells carry oxygen, so someone with anaemia can feel weak, tired and short of breath.
 
Analgesic nephropathy:  Kidney disease caused from over use of analgesic (pain-relieving) medications.
 
Anti-bodies:  Are made by the immune system, your body's protection mechanism, to attack tissue that is not normally part of the body, for example bacteria or toxins.

Artery:  A large blood vessel that takes blood from the heart to other parts of the body.

Atherosclerosis:  A thickening or hardening of the arteries.
 
Automated Peritoneal Dialysis (APD):  See Continuous Cycling Peritoneal Dialysis (CCPD).

Autosomal Recessive Polycistic Kidney Disease (ARPKD):  A genetic disease that is inherited in a random fashion. In recessive disorders such as ARPKD, the baby must inherit a copy of the disease gene from each parent in order to be affected.

B

Bag exchanges:  Refers to one complete treatment cycle of peritoneal dialysis. See Peritoneal Dialysis.

Basal Cell Carcinoma (BCC):  A type of skin cancer

Buttonhole technique:  A technique that is sometimes used to insert needles into a fistula.

Bicarbonate:  A soluble mineral salt or mixture of salts that can neutralise acids.
 
Biopsy:  A small piece of tissue is removed for testing and examination under a microscope.
 
Bladder:  A thin, elastic sac or membrane inside the body that stores the urine (wee).

Blood group:  There are four blood groups, O, A, B, AB. In the first instance, blood group determines whether someone can receive a donor kidney.
 
Blood Typing:  Usually refers to the red blood cell groups (O, B, A or AB) that govern the compatibility for blood transfusion. In the kidney world it may also mean the white cell or HLA typing that governs the compatibility for organ transplantation.

Blood Vessels:  The tubes that take blood around the body.

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C

Catheter:  A plastic tube that is used to take fluid in or out of the body.

Chemotherapy:  Chemotherapy is the use of drugs to treat cancer. The chemotherapy drugs attack and kill the fast-growing cancer cells.

Chronic Kidney (renal) Disease (CKD):  A term used widely to describe kidney damage or reduced kidney function (irrespective of the cause) that persists for more than 3 months. Sometimes CKD leads to kidney failure, which requires dialysis or a kidney transplant to keep you alive.
 
Complete proteins:  Foods, such as meat, fish and eggs, which contain all of the protein-building materials that a body needs.
 
Continuous Ambulatory Peritoneal Dialysis (CAPD):  A type of dialysis where a special fluid is put into the peritoneal cavity (abdomen) through a soft, plastic tube (catheter) then drained out a few hours later. This is usually done 3 or 4 times during the day to clean the blood. by the kidneys and passes out in the urine (wee). When the kidneys aren’t working very well, the creatinine stays in the blood and the measured level is elevated.

Continuous Cycling Peritoneal Dialysis (CCPD):  Very similar to CAPD but the fluid is moved in and out of the body continuously for a few hours by a machine, usually at night. Also called Automated Peritoneal Dialysis (APD).

Cramps:  Many people with kidney failure get muscle cramps. Imbalances in fluid and electrolytes, nerve damage or blood flow problems are thought to be some of the causes. Some people experience cramps during or after haemodialysis and this may be due to a drop in blood pressure or a rapid loss of fluid or sodium.

Creatinine:  Waste that is made by the breakdown of muscles. It is usually removed from the blood.

Cysts:  Are sacs filled with clear fluid. Cysts can develop with age, kidney disease or be inherited. There can be one or many cysts, which can be simple or complicated.

Cytomegalovirus:  Is a virus that is a member of the herpes family. In healthy people, CMV can lead to a flu-like illness that lasts a few days. People with transplants are more at risk of serious complications of this virus.

D

Diabetes:  Is a chronic disease caused by problems with the production and/or action of insulin in the body. 

Diabetic Kidney Disease:  A serious outcome of diabetes, which affects the kidney filters and can lead to kidney failure. 

Diabetes Mellitis:  A condition characterized by high blood glucose (sugar) resulting from the body's inability to use glucose efficiently. Insulin normally helps the body's cells use glucose. In type 1 diabetes, the pancreas makes little or no insulin; in type 2 diabetes, the body is resistant to the effects of available insulin.

Diagnosis:  Giving a sickness a name based on the symptoms.
 
Dialyser:  Part of a dialysis machine that filters blood to remove waste products and excess fluid.
 
Dialysate:  A special fluid used in dialysis to remove waste and extra fluid from the blood.
 
Dialysis:  A treatment for kidney failure that removes waste products and extra water from the blood by filtering the blood through a special membrane to remove waste products. There are two types of dialysis, haemodialysis and peritoneal dialysis. The type of dialysis used depends on age, lifestyle, overall health and other factors.

Dialysis fluid:  A special fluid that is used during dialysis to help clean the waste and excess fluid from the blood.

Dialysis nurse:  If you are on dialysis, you may become closest to your dialysis nurse. He or she specialises in dialysis treatment. Your dialysis nurse can teach you about the advantages and disadvantages of different kinds of dialysis. Dialysis nurses also help train people to do dialysis themselves.

Dialysis session:  Length of time spent on dialysis according to specialists prescription.

Dialysis solution:  A cleansing liquid used in the two major forms of dialysis- are haemodialysis and peritoneal dialysis. Dialysis solution contains dextrose (a sugar) and other chemicals similar to those in the body. Dextrose draws wastes and extra fluid from the body into the dialysis solution.

Dialysis specialists:  Nurses and other healthcare professionals who manage dialysis procedures and/or instruct patients how to manage their own dialysis.

Dietician:  A health professional - someone trained in nutrition and diet planning.
 
Donor:  A person who gives a body organ to another person, such as a kidney. For kidneys, the donor can be living or deceased.

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E

Electrolytes:  Elements or chemicals needed to enable the body and heart to work properly.
 
End stage kidney (renal) disease (ESKD):  The stage in kidney disease when a person's kidneys have stopped working so treatment is needed to sustain life, such as dialysis or a transplant. See Chronic Kidney (renal) Disease (CKD)

End stage kidney (renal) failure (ESKF):  Total kidney failure that cannot be reversed. Treatment is needed such as dialysis or a transplant. See Chronic Kidney (renal) Disease (CKD)
 
Energy foods:  Foods, particularly sugar and fats, which provide the body with energy. Usually measure in calories or kilojoules.
 
Erythropoietin (EPO):  A body chemical (hormone) mainly made by the kidneys that causes the bone marrow to make red blood cells. A lack of this hormone can cause anaemia.
 
Exchange:  One complete treatment cycle of peritoneal dialysis.

F

Ferritin:  A form of storage iron.

Fistula:  Produced when a vein and an artery in the arm or leg are joined together in an operation to make it easier to move blood in and out of the body during haemodialysis.

Fluid allowance/restriction:  Is a limit or daily total amount of fluid taken daily that is usually set by a doctor or your healthcare team.
 
Fluid Retention:  When the body does not get rid of enough liquid (water). This can cause swollen or puffy ankles, face or hands or shortness of breath.

Focal Segmental Glomerulosclerosis:  (FSGS) scrarring of glomeruli (units within kidney where blood is cleaned)

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G

Glomerular filtration rate (GFR):  GFR is the best measure of kidney function and helps to determine the stage of kidney disease. It shows how well the kidneys are cleaning the blood. GFR is reported in milliliters per minute. The GFR is usually worked out from the results of the creatinine blood test with age and gender. The GFR helps the doctor plan your treatment. A normal GFR is greater than 90 mL/min.

Glomerulus:  A tiny set of blood vessels in the nephron.

Glomerulonephritis:  A type of kidney disease that damages the tiny filters in the kidneys. It is sometimes called nephritis.
 
Glomeruli:  See nephron.

Goodpasture's Syndrome:  An uncommon disease that affects both the kidneys and lungs.
 
Graft:  Another type of access for haemodialysis that is used if the blood vessels cannot be used for a fistula. During surgery an artery and a vein are joined together by soft tubing.

H

Haematuria (or blood in the urine):  Occurs when red blood cells leak into the urine. It can turn urine a red or dark cola colour, which is visible to the eye or may only be found by a urine test, which is called microscopic haematuria. Blood in the urine is a common sign of urinary tract infections but can be the first sign of a problem with the kidneys or the bladder.

Haemodialysis:  A treatment for kidney failure. The patient's blood is pumped through special tubing to a haemodialysis machine. The machine acts like a kidney, filtering waste products from the blood before returning it to the patient. Haemodialysis usually lasts for 4-6 hours and is done 3 or more times a week.

Haemoglobin:  A part of the red blood cells that carries oxygen around the body.

Haemolytic Uremic Sydnrome (HUS):  Rare condition affecting mostly children under the age of 10, characterized by destruction of red blood cells, damage to the lining of blood vessel walls, and, in severe cases, kidney failure. Most cases of HUS occur after an infection in the digestive system caused by bacteria-contaminated food like meat, dairy products, and juice. The first stages of HUS frequently present with gastrointestinal symptoms such as abdominal pain, vomiting, and bloody diarrhoea.
 
Health:  Physical, mental, emotional and spiritual wellbeing, not merely an absence of disease.
 
Heparin:  Added to the blood during haemodialysis to stop it from clotting (forming small lumps) and blocking the dialyser.

Home Haemodialysis:  People are trained to perform haemodialysis in their own homes.  People on home dialysis often report feeling more independent.
 
Hormone:  A chemical made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. They also affect moods.

Hypoglycemia:  Low blood glucose. Most cases occur when there is too much insulin and not enough sugar in your body.
 
Hypertension:  Another word for high blood pressure. High blood pressure can cause chronic kidney disease and chronic kidney disease can cause high blood pressure.

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I

IgA Nephropathy:  A common type of glomerulonephritis. It causes blood in the urine and is often linked to sore throats and pain at the top of the legs.

Immunosuppressant:  Medications taken following a transplant to prevent rejection.

In centre Haemodialysis:  Usually performed in hospital, satellite unit or private clinic three times a week for around 5 hours.
 
Incomplete proteins:  Foods, such as fruits, vegetables and cereals, which do not contain all of the protein-building materials that a body needs.
 
Insulin:  A chemical or hormone made by the pancreas that controls the level of glucose (sugar) in the blood.
 
Intermittent peritoneal dialysis (IPD):  Form of peritoneal dialysis in which exchanges are done hourly for two or three days each week. Jugular vein: blood vessel located in the side of the neck sometimes used to provide access for haemodialysis. Incomplete proteins: foods, such as fruits, vegetables and cereals, which do not contain all of the protein-building materials that a body needs.

J

Jugular vein:  A large blood vessel located in the side of the neck sometimes used to insert a catheter (tube) for haemodialysis.

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K

Kidneys:  Reddish, jelly bean-shaped body organs. Most people have two kidneys but people can live with one. The kidneys are in the lower back just under the bottom of the rib cage. A kidney is about the size of your fist. The kidneys are very important because they remove waste and fluid from the body and produce urine (wee). They also help to:

• Control blood pressure
• Produce red blood cells
• Keep our bones strong
• Maintain the chemical balance of the blood
• Change Vitamin D so that the body can use it
• Get rid of drugs and poisons

Kidney Biopsy:  A diagnostic test where a needle is used to remove a small piece of tissue from a kidney. A biopsy helps to determine the cause of kidney disease.

Kidney Failure:  When the kidneys stop working. Kidney failure can be temporary (acute) or permanent.

Kidney Function:  Blood tests are taken regularly from kidney patients to monitor how well the kidneys are cleaning the blood.

Kidney Transplant:  When a healthy kidney is taken from one person and surgically placed into someone with kidney failure. The kidney can come from a live or deceased donor. It is important to remember that a transplant is a treatment not a cure for kidney disease.

Kidney Ultrasound Scan:  A probe is moved over the skin, sending and receiving ultrasound signals, which then make pictures of the kidneys and bladder. This is a diagnostic test, often used to measure the size of the kidneys.

Kilojoules:  A metric measure of the energy value of food (previously called calories). Lipid: another name for fats that cannot usually be dissolved in water. M Melanin pigment: a substance that naturally colours the hair and skin.

M

Membrane:  A thin, elastic lining or sac connecting or covering parts of the body.
 
Metabolic:  The chemical processes of the body.
 
Microalbuminuria:  It is often an early warning of kidney disease if found in urine but can also be present for other reasons. It can mean that your kidneys are damaged so albumin, a kind of protein, leaks into the urine in very small or 'micro' amounts. The level can be measured by a special urine test either on a single urine sample or timed urine collection. Normal values on this test are less than 15 to 30 mg/l. A microalbumin test should be done at least yearly if you have diabetes.

Mixed Connective Tissue Disease:  A chronic inflammatory autoimmune disease that may affect the kidneys.

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N

Nephritis:  See glomerulonephritis.
 
Nephrologist:  A doctor who specialises in kidney function.

Nephrology:  The study of the kidneys.
 
Nephron:  The tiny parts of the kidney that filter blood to make urine (wee). There are over one million filters in each kidney.

Nocturnal Home Haemodialysis:  A form of haemodialysis available in some regions.  Dialysis occurs whilst you are asleep.  Dialysis occurs whilst you are asleep.  Dialysis usually takes place at home for around eight hours, six nights a week.

O

Oedema:  See fluid retention
 
Organs:  Parts of the body that help us to stay alive, such as the kidneys, heart, lungs and liver.
 
Osmosis:  The movement of molecules from a high concentration to a low concentration across a membrane.
 
Outpatient clinic:  A service for patients who are not staying in the hospital.

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P

PD cycler:  See Continuous Ambulatory Peritoneal Dialysis (CAPD).

Percent of kidney function:  An estimate of the level that each kidney is working. A GFR of 100 milliliters per minute (mL/min) is in the normal range so it is useful to say that 100 mL/min is about equal to '100% kidney function'. A GFR of 30 mL/min could be called '30% kidney function'.

Peritoneal cavity:  The space in the abdomen (belly) holding the intestines and other organs.
 
Peritoneal dialysis (PD):  A treatment for kidney failure where dialysis fluid is moved in and out of the peritoneal cavity to remove wastes and fluid from the blood. (See CAPD and CCDP)
 
Peritoneum:  A very, thin sac or membrane that surrounds the organs on the inside of the abdomen or peritoneal cavity.
 
Peritonitis:  A bacterial infection in the peritoneum.

Permacath:  An access device for haemodialysis. It is a catheter that is usually placed in the neck or groin so that blood can flow to the artificial kidney or dialyser.
 
Phosphate:  A mineral together with calcium, that keeps your bones strong and healthy. The kidneys help to control the amount of phosphate in the body. Phosphate helps to keep the bones and other body parts strong and healthy. Too much phosphate causes itching and pain in the joints, such as the knees, elbows and ankles. When the kidneys are not functioning properly, high levels of phosphate accumulate in the blood. The amount of phosphate you are allowed depends on your blood tests. 
 
Phosphate binder:  You may be prescribed medicine called phosphate binders that combine with phosphate in your intestines so it will pass out of your body with the faeces (poo). It is important to take phosphate binders with your meals and snacks.
 
Polycystic Kidney Disease:  An inherited kidney disease that produces fluid-filled cysts in the kidneys.
 
Potassium:  An essential mineral, which helps nerve endings and muscles to work. If your level of potassium is too high or low, it can cause an irregular heartbeat. In fact, very high potassium levels may cause the heart to stop. The usual range of potassium is 3.5 - 5.0mmol/L.
 
Protein:  A nutrient that you get from good that builds, repairs and maintains body tissue. It also helps to fight infections and heal wounds.
 
Proteinuria:  Occurs when there are abnormal levels of protein in the urine. Usually, protein is not removed when the kidneys filter waste from the blood. However, when the kidneys are damaged protein leaks through the damaged filters and leaves in the urine, along with the waste. The appearance of protein in the urine may be the first sign of an otherwise silent kidney condition.

R

Recipient:  A person who gets a new body organ, such as a kidney.
 
Reflux nephropathy:  A kidney condition caused by the backflow of urine from the bladder up the ureters into the kidney that affects children.
 
Renal:  Another word for kidney or about the kidneys.

Renal biopsy:  A needle is passed through your skin to the kidney. A small piece of kidney tissue is removed for
examination under a microscope.
 
Renal failure:  Failure of kidney function.
 
Renin:  A chemical made by the kidneys that helps control blood pressure.

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S

Salt:  Affects the amount of fluid the body retains and increases thirst. If you have a kidney problem, too much salt can make you drink more than your kidneys can remove and may cause:

• High blood pressure
• Swelling of ankles, feet, hands and puffiness under the eyes
• Shortness of breath

Sodium:  A mineral in the body, which is often called '"salt". The kidneys help to control the amount of sodium in the body. Sodium helps to control the amount of water in the body.

Steroid:  A medicine that helps to stop swelling and the body damaging a new organ, such as a kidney.
 
Subclavian vein:  A blood vessel found underneath the shoulder that is sometimes used for haemodialysis.

T