Acidosis Buildup of acid in the blood.
Adrenal glands Small endocrine glands sitting atop the kidneys that secrete aldosterone, promoting fluid and salt retention.
Albuminuria Protein in the urine. Urine with high amounts of protein is called macroalbuminuria, while urine with low amounts is called microalbuminuria.
Aldosterone See Adrenal glands.
Anemia Low red blood cell count.
Aneurysm Ballooning of a major blood vessel that can rupture, causing massive bleeding.
Angiotensin-converting enzyme (ACE) Enzyme that stimulates the conversion of angiotensin I to angiotensin II.
Angiotensin system System that regulates blood pressure when salt concentration is low; renin reacts with angiotensinogen, which stimulates the conversion of angiotensin I to angiotensin II, which then constricts blood vessels to raise blood pressure.
Antibody A protein created by the immune system to attack and destroy foreign entities like microorganisms and organs transplanted from other people.
Antigen “Nametag” on cells that identifies the cells as belonging to a specific individual.
Atherosclerosis Buildup of plaque in blood vessels that can contribute to hypertension.
Autosomal dominant polycystic kidney disease (ADPKD) Dominant form of PKD; a child has a 50 percent chance of inheriting the disease from an affected parent.
Autosomal recessive polycystic kidney disease (ARPKD) Recessive form of PKD; a child has a 25 percent chance of inheriting the disease if both parents are carriers of the mutated gene, but the parents do not have ARPKD themselves.
Biopsy A procedure in which a small amount of tissue is removed from the body for investigation and testing.
Blood typing The means for determining one person’s blood type compatibility with another person’s blood type. Compatible blood typing is needed for kidney transplantation.
Blood urea nitrogen (BUN) A measure of kidney function. A high value indicates declining kidney function.
Bone marrow Soft tissue in bone that makes red blood cells.
Calcidiol An intermediate form of vitamin D in the production of calcitriol.
Calcitriol The most active form of vitamin D that the body uses. It does not require activation by the kidney and is often given to dialysis patients who cannot make their own calcitriol.
Calcium An important mineral in keeping bones strong and a mediator in many biochemical pathways.
Carbohydrates A group of sugars and starches that are a source of energy for the body.
Carbon dioxide The main substance in exhaled breath. In the form of bicarbonate, it neutralizes acidity in the blood.
Catheter Access to a major vein. Catheters are used primarily for dialysis but can be a means of administering medications or nourishment. They can also be used to drain urine from the bladder.
Cholecalciferol The form of vitamin D typically found in supplements. Cholecalciferol does not have to be activated in the skin. See Vitamin D.
Chromosome Structure within the nucleus of the cell that houses the genetic code. Each cell contains twenty-three pairs.
Continuous Ambulatory Peritoneal Dialysis (CAPD) A form of dialysis that requires four to five manual exchanges of abdominal fluid per day.
Continuous Cyclic Peritoneal Dialysis (CCPD) A form of dialysis that uses a machine (cycler) to perform exchanges during the night; some manual exchanges are needed during the day.
Creatinine A measure of kidney function. Creatinine is completely filtered by the kidney, making it a more accurate measure than BUN. A high value indicates declining kidney function.
Creatinine clearance The amount of creatinine filtered by the kidney and passed into the urine. This is the most accurate measure of kidney function.
Crossmatch The last test performed to avert rejection of a donated kidney. A negative test result allows the transplantation to proceed.
Deoxyribonucleic acid (DNA) Blueprint for life; DNA is composed of long strings of nucleotide sequences containing the instructions for making up to three proteins.
Diabetic nephropathy Diabetes-induced kidney failure.
Dialysate The solution drained from the abdomen during a peritoneal dialysis exchange; also, the solution bathing a dialyzer in a hemodialysis machine.
Dialysis A method of cleansing the blood of waste products.
Dialyzer A filter used in hemodialysis containing tiny filaments bathed with dialysate; blood passes through the filaments and toxins diffuse into the dialysate.
Edema Accumulation of fluid in soft tissues of the body, especially in the legs and ankles.
Electrolytes Salts, like sodium and potassium, which control many functions in the body.
Erythrocytes Red blood cells, which carry oxygen throughout the body.
Erythropoietin (EPO) A hormone made by the kidney to stimulate production of red blood cells (erythrocytes) in bone marrow.
Exchange The process in peritoneal dialysis by which the dialysate is replaced.
Fistula A vascular access created by joining an artery and a vein in an arm or leg, used for hemodialysis.
Genes The instructions for making and running a cell; genes are composed of sequences of DNA.
Glomerular filtration rate (GFR) A measurement similar to creatinine clearance, but calculated from blood creatinine taking into account age and race.
Glomerulus A structure in the kidney that filters blood of its waste products.
Glucose The main source of energy in the body.
Graft A vascular access created by joining an artery and vein to each end of a Gortex tube, used for hemodialysis.
Hematocrit The volume of blood comprising red blood cells.
Hemodialysis Filtration of the blood with a machine that circulates blood through a dialyzer.
Hemoglobin A protein in red blood cells that carries oxygen through the body. Hemoglobin levels can drop as kidneys fail.
Heparin A blood thinner used in hemodialysis to avoid clotting in the tubing and dialyzer.
HLA typing The means for determining one person’s cells’ immune compatibility with another person’s cells. HLA typing is used for matching donors to recipients for a kidney transplant.
Homeostasis The process of keeping conditions in the body within a normal range.
Hormones Substances, like aldosterone and leptin, acting on receptors that change physiological function.
Hyperlipidemia Elevated blood fats like cholesterol, saturated fats, and triglycerides.
Hypertension Blood pressure above 140/90.
Incidence The number of new cases of a disease.
Insulin A pancreatic protein that regulates glucose levels in the blood by helping glucose pass into cells.
Insulin resistance Reduced ability of insulin to enter cells, even when blood insulin levels are high.
Kidney failure A condition when elimination of wastes from the body no longer takes place.
Kt/V A measure of efficiency in hemodialysis.
Leptin A hormone that regulates hunger by reducing appetite; leptin may play a role in Type 2 diabetes.
Lymphocytes Cells within the immune system that protect the body from foreign organisms. T-lymphocytes attack transplanted organs, causing rejection.
Metabolites Substances formed through a series of biochemical reactions. For example, protein is broken down to urea.
Mutations Mistakes made in copying genes that can cause a malfunction in cellular processes and can lead to a disease like PKD.
Nephron The basic unit of the kidney, composed of a glomerulus, tubules, and collecting ducts.
Osteoporosis A condition in which excess amounts of calcium are removed from bones, making them brittle and more easily fractured.
Panel Reactive Antibody (PRA) A test to measure the amount of antibodies in the blood to assess the likelihood of kidney rejection. The higher the value, the greater the potential for rejection.
Parathyroid hormone A hormone secreted from the two parathyroid glands in the neck that promotes removal of calcium in bone into the blood. This action can lead to osteoporosis.
Peritoneal dialysis Filtration of the blood with a solution in the abdomen.
Peritoneal equilibrium test (PET) A method to determine the adequacy of peritoneal dialysis by measuring the creatinine and urea in four hourly samples.
Peritonitis Inflammation of the lining of the abdomen.
Pharmacogenetics The use of genetic information to develop new medications. Specific mutations in genes and accompanied altered protein structure can suggest mechanisms underlying a disease that can be potential targets for therapeutic intervention.
Phosphorus An important substance in the generation of energy. Phosphorus accumulates in hemodialysis patients and can combine with calcium in the blood to form plaques in organs, possibly leading to organ failure.
Polycystic kidney disease (PKD) An inherited disease characterized by cysts that grow and ultimately destroy kidney function.
Polygenetic diseases Diseases caused by mutations in multiple genes.
Potassium A salt that helps regulate heart beat and brain function. High blood potassium levels can lead to heart block. Usually high potassium can be treated by altering the diet or prescribing medications.
Prevalence The total number of people with a disease at a given time.
Proteins Long chains of amino acids that operate cells and provide structure for the body.
Receptors Entities on or within cells that translate a signal from a hormone or drug into a physiological response; receptors are specific for certain chemical structures, like a key fitting a lock.
Renin A substance released from the kidney that activates the angiotensin system (see Angiotensin system). Under normal conditions it helps maintain blood pressure during dehydration or extreme blood loss.
Restless legs syndrome A neurological disorder that can affect people on hemodialysis, who experience an uncontrollable urge to move their legs.
Sodium A principal substance (salt) that determines how much fluid the body retains.
Transplantation Organ replacement therapy where an organ is removed from one individual (a donor), either living or deceased, and placed in a recipient.
Urea Breakdown product of protein. Urea is the main substance excreted by the kidney.
Uremia Excess amount of urea in the blood, which can cause death in kidney failure patients without dialysis or transplantation.
Ureters Long tubes that connect the kidneys to the bladder.
Urinalysis A method used to detect blood or protein in the urine.
Urinary reduction rate (URR) A measure of efficiency of hemodialysis.
Vasopressin A hormone released by the pituitary gland that acts on the kidney to retain fluid.
Vitamin D A fat-soluble vitamin needed to form and maintain strong bones. Vitamin D can be made naturally or supplied in the diet or with supplements. The kidney makes the most active form of vitamin D, and when kidneys fail, bone structure can degrade, requiring treatment with the most active form. This problem is most common in hemodialysis patients.
Xenotransplantation Transplantation of an organ from one species to another.