Acute renal insufficiency – Rapid, sudden loss of kidney function, often reversible, but not always.

Anemia – Medical condition in which the number of red blood cells is reduced.

Antibody – A protein produced in the body in response to invasion by foreign material (antigen).

Antigen – Any substance not normally present in the body which causes production of an antibody.

Antithymocyte globulin (ATG) – Medication used to prevent or treat rejection of a transplanted kidney.

Artery – Blood vessel taking blood from the heart to other parts of the body.

Artificial Kidney – See dialyzer.

Assisted continuous ambulatory peritoneal dialysis (ACAPD) – Form of continuous peritoneal dialysis using simple equipment so that an extra exchange or exchanges can be done while you sleep.

Autosomal dominant Polycystic kidney disease (ADPKD) – Inherited kidney disease which produces fluid-filled cysts in the kidneys and other organ systems.

Azathioprine – Medication used to prevent rejection of a transplanted kidney.

Bladder – An expandable sack which collects and holds urine.

Cadaveric transplant – Type of kidney transplant in which a kidney is donated from someone who has died suddenly.

Calcium – Mineral that is important for bone growth and body function.

Calories – Measure of energy value of food.

Catheter – Hollow tube used to transport fluids to or from the body.

Cholesterol – A type of fat found in most body tissues.

Chronic renal insufficiency (CRI) – Slow and progressive deterioration of kidney function. Also called kidney failure, usually irreversible.

Continuous ambulatory peritoneal dialysis (CAPD) – Form of continuous peritoneal dialysis in which dialysis fluid is exchanged at regular intervals throughout the day.

Continuous cycling peritoneal dialysis (CCPD) – Form of continuous peritoneal dialysis in which a machine called an automatic cycler performs regular exchanges throughout the night.

Continuous peritoneal dialysis (CPD) – Forms of peritoneal dialysis in which the peritoneal cavity is continuously filled with dialysis fluid.

Creatinine – Waste product of muscle activity.

Cross match – Blood test to measure the compatibility of a transplant donor and recipient.

Cyclosporine – Medication used to prevent rejection of a transplanted kidney.

Cytotoxic antibody – Substance in the blood which may cause the body to reject a transplanted kidney.

Daily eating plan – Plan worked out by a dietitian and a kidney patient which determines the types and amounts of foods which should be eaten daily.

Diabetes mellitus – Disease of the pancreas in which the production of insulin is decreased. Commonly called diabetes.

Dialysis – From Greek, meaning "to separate or dissolve". A treatment for kidney failure which removes wastes and water from the blood.

Dialysis fluid – Special fluid used in dialysis into which wastes are passed.

Dialyzer – The part of an artificial kidney machine which acts like a filter to remove wastes from the blood.

Dry weight – The body weight achieved when extra fluid is removed during dialysis. Sometimes called target weight.

Edema – Swelling of the body tissues due to salt and water retention.

End-stage renal disease (ESRD) – Stage in kidney disease when treatment, such as dialysis or transplantation, becomes necessary. "End-stage" refers to the end of kidney function. Also called end-stage kidney disease.

Energy foods – Foods, particularly sugars and fats, which provide the body with energy. Usually measured in calories.

Erythropoietin (EPO) – Hormone which stimulates the bone marrow to produce red blood cells.

Exchange – One complete cycle of peritoneal dialysis, consisting of inflow, equilibrium, and outflow.

Fistula – Commonly used method of providing access to the bloodstream in which a vein and an artery in the arm are joined together.

FK506 – Medication used to prevent rejection of a transplanted kidney. See tacrolimus.

Glomerulonephritis – Condition in which the glomeruli, the tiny filters which clean the blood, are damaged. Often referred to as nephritis. There are many causes.

Glomerulus – Microscopic filter in the kidney which separates excess water and wastes from the blood.

Graft – A vein and an artery in the arm are joined with a piece of special tubing. The graft provides access to the bloodstream for dialysis.

Hemodialysis – Treatment for kidney failure in which the blood passes through a dialyzer to remove wastes and water.

Heparin – Substance added to blood during hemodialysis to prevent it from clotting in the dialyzer.

Hormone – Chemical messenger which regulates bodily functions such as blood pressure and the making of red blood cells.

Hypertension – High blood pressure. May be either the cause or the result of kidney disease.

Immune system – System which protects the body from foreign material such as viruses and bacteria.

Immunosuppressants – Medications which suppress the body’s immune system and help prevent rejection of a transplanted kidney.

Insulin – Hormone produced by the pancreas which regulates the level of glucose (sugar) in the blood.

Jugular vein – Blood vessel located in the side of the neck sometimes used to provide access for hemodialysis.

Kidney – One of two organs located at the back of the abdominal cavity on each side of the spinal column.

Kidney failure – Progressive deterioration of kidney function. Also call chronic renal insufficiency.

Living donor transplant – Type of kidney transplant in which a kidney is donated by a living donor, usually a blood relative.

Lupus – Commonly used term for systemic lupus erythematosus.

Lymphocytes – Cells of the immune system which are involve in transplant rejection.

Membrane – Porous material which is used to filter wastes from the blood.

Muromonab CD-3 – Medication used to treat or prevent rejection of a transplanted kidney.

Mycophenolate mofetil – Medication used to prevent rejection of a transplanted kidney.

Nephritis – See glomerulonephritis.

Nephron – The functional unit of the kidney which acts to maintain the body's chemical balance. Consists of a filter attached to a tubule.

Peritoneal cavity – Abdominal cavity which contains the intestines and other internal organs.

Peritoneal dialysis – Treatment for kidney failure in which dialysis fluid is introduced into the peritoneal cavity to remove wastes and water from the blood.

Peritoneum – Thin membrane which encloses the peritoneal cavity and surrounds the abdominal organs.

Phosphate binder – Medication which binds with phosphate in the intestine causing excess phosphate to be passed in the stool.

Phosphorus (phosphate) – Mineral in the body fluids regulated by the kidneys. At normal levels, keeps bones strong and healthy. At high levels, causes itching and painful joints.

Platelets – Cells in the blood which are involved in blood clotting.

Potassium – Mineral in the body fluids regulated by the kidneys. At normal levels, helps nerves and muscles work well. At high levels, may result in heart failure and death.

Prednisone – Medication used to prevent rejection of a transplanted kidney. May also be used to treat rejection in higher doses given intravenously.

Protein – Substance obtained from food which builds, repairs and maintains body tissues. High sources of protein are mainly from animal foods.

Reflux nephropathy – Condition in which the kidneys are scarred because of an abnormal flow of urine from the bladder into the kidney.

Rejection – Process in which the body recognizes that a transplanted kidney is not its own and mobilizes the immune system to fight against it.

Renal artery – Major vessel which delivers blood to the kidneys for cleaning.

Renal pelvis – Funnel-like structure which collects urine from the kidney and delivers it to the ureter.

Renal Replacement Therapy – A treatment, such as dialysis or transplantation, which attempts to replace the normal functioning of the kidneys.

Renal vein – Major vessel which returns freshly cleaned blood from the kidneys to the circulatory system.

Renin – Hormone produced by the kidneys which regulates blood pressure.

Serum creatinine level – Blood test to measure the level of creatinine, which is a waste product of muscle activity. As kidney function decreases, the serum creatinine level increases.

Sodium – Mineral in the body fluids regulated by the kidneys. Affects the level of water retained by the kidneys.

Steroid – Medication which reduces inflammation and acts as an immunosuppressant. Prednisone is an example. Not to be confused with anabolic steroids, which are medications sometimes used by athletes.

Subclavian vein – Blood vessel located underneath the collarbone sometimes used to provide access for hemodialysis.

Systemic lupus erythematosus – Disease of the immune system which may affect a number of organs, including the kidneys.

Tacrolimus (FK506) – Medication used to prevent rejection of a transplanted kidney.

Target weight – The body weight achieved when extra fluid is removed during dialysis. Sometimes called dry weight.

Tissue typing – Laboratory test to determine the genetic makeup of a person. Used to ensure compatibility of a kidney before transplant.

Tubule – Tube in the nephron which collects and processes urine from the glomeruli before the urine passes into the pelvis.

Ultrafiltration – Process in which blood entering a dialyzer is placed under pressure to remove excess water.

Urea – Waste product from the breakdown of protein.

Uremia – Condition caused by a build-up of waste products in the blood.

Ureter – Tube which takes urine from the renal pelvis and delivers it into the bladder.

Urethra – Tube from the bladder which takes urine out of the body.

Urinalysis – Test to measure the presence of protein and other substances in the urine.

Vein – Blood vessel returning blood to the heart.

White blood cells – Cells in the blood which fight infection and are active in the process of kidney rejection.