| Term | Definition |
| Acute Kidney Injury (AKI) | A sudden episode of kidney failure or kidney damage. |
| Afferent Arteriole | The blood vessel that carries blood into the glomerulus. |
| Albuminuria | The presence of albumin (a protein) in the urine. |
| Allograft | An organ or tissue transplanted from one person to another. |
| Alport Syndrome | A genetic disorder affecting kidney filters and hearing. |
| Amyloidosis | A build-up of abnormal proteins in the kidneys. |
| Anastomosis | The surgical connection between blood vessels or ureters. |
| ANCA+ve Vasculitis | Autoimmune inflammation of small blood vessels in the kidney. |
| Anaemia | A lack of red blood cells, common in kidney disease. |
| Angiotensin II | A hormone that constricts blood vessels to raise pressure. |
| Anion Gap | A measurement used to help diagnose metabolic acidosis. |
| Anuria | The failure of the kidneys to produce urine. |
| AV Fistula | A surgical connection for long-term dialysis access. |
| ADPKD | Genetic disorder causing many cysts in the kidneys. |
| Azotaemia | High levels of nitrogenous waste products in the blood. |
| Balkan Nephropathy | A chronic interstitial disease found in specific regions. |
| Basement Membrane (GBM) | The filtration layer within the glomerulus. |
| BK Virus (‘BK’) | A virus that can cause graft failure after transplant. |
| BUN | Test measuring urea, a waste product of protein. |
| Bowman’s Capsule | The part of the nephron that collects filtered fluid. |
| Bruit | The sound of blood rushing through a dialysis fistula. |
| Cadaveric Donor | An organ donated by an individual who has died. |
| Calciphylaxis | Calcium buildup in small blood vessels of fat and skin. |
| Calcineurin Inhibitors | Anti-rejection medications like Tacrolimus and Ciclosporin. |
| Calcium Oxalate | The primary component of most kidney stones. |
| Cannulation | Inserting needles into a fistula for dialysis treatment. |
| Cast | Microscopic structures in urine indicating kidney stress. |
| CKD | Long-term, gradual loss of kidney function. |
| Clearance | The rate at which the kidney removes a substance. |
| Cold Ischaemia Time | Time an organ is kept on ice during transport. |
| Complement System | Immune components that can cause graft rejection. |
| Creatinine | A waste product used to estimate filtration rates. |
| Crossmatch | Testing donor and recipient blood for compatibility. |
| Cystoscopy | Procedure to examine the bladder using a camera. |
| CMV | A common virus problematic for transplant patients. |
| Deceased Donor | An organ donor who has passed away. |
| Delayed Graft Function | When a new kidney does not work immediately. |
| Desensitisation | Reducing antibodies to allow ‘incompatible’ transplants. |
| Dialysate | Fluid used to pull toxins out of the blood during dialysis. |
| Dialyser | The filter used in a haemodialysis machine. |
| Distal Tubule | The nephron segment regulating electrolytes and pH. |
| Diuretic | Medication used to increase urine production. |
| Dry Weight | A patient’s weight without excess fluid buildup. |
| Echogenic | How bright a kidney appears on an ultrasound. |
| Ectopic Kidney | A kidney located in an abnormal part of the body. |
| Edema / Oedema | Swelling caused by fluid retention in tissues. |
| Efferent Arteriole | The vessel carrying blood away from the glomerulus. |
| Electrolytes | Essential minerals like sodium and potassium. |
| ESRD | Kidney failure requiring dialysis or transplant (Stage 5 CKD). |
| Erythropoietin | Hormone that stimulates red blood cell production. |
| eGFR | Estimated glomerular filtration rate. The standard calculation for kidney function level. |
| Fanconi Syndrome | A disorder of the proximal tubules. |
| Fibromuscular Dysplasia | A cause of narrowing in the renal arteries. |
| Filtration Fraction | The proportion of plasma filtered by the kidney. |
| FSGS | Scarring in specific parts of the kidney filters. A type of chronic glomerluonephritis. |
| Fresenius | A major provider of dialysis services and machines. |
| Graft | The general term for the transplanted organ. |
| Glomerulonephritis | Inflammation of the kidney’s filtering units. |
| Glomerulus | A network of capillaries where filtration occurs. |
| Gluconeogenesis | The kidney’s ability to produce new glucose. |
| Glycosuria | The presence of sugar in the urine. |
| Haematuria | The presence of blood in the urine. |
| Haemodialysis | Filtering blood through a machine outside the body. |
| Haemofiltration | A continuous therapy used for critically ill patients. |
| Henle, Loop of | Nephron segment that concentrates the urine. |
| Horseshoe Kidney | A condition where both kidneys are fused together. |
| HLA | Markers used to match donors with recipients. |
| Hyperkalaemia | Dangerously high levels of potassium in the blood. |
| Hypernatraemia | High sodium levels, often due to dehydration. |
| Hypertension | High blood pressure, a major cause of kidney damage. |
| Hypoalbuminaemia | Low blood protein levels causing fluid leaks. |
| IgA Nephropathy | Kidney disease caused by IgA deposits. A type of glomerulonephritis |
| Immunosuppression | Medications to prevent the body from rejecting a graft. |
| Induction Therapy | Powerful initial drugs given during transplant surgery. |
| Interstitial Nephritis | Inflammation of the kidney’s connective tissue. |
| Ischaemia | Inadequate blood supply to the kidney. |
| Juxtaglomerular Apparatus | Cells that help control blood pressure via renin. |
| Kt/V | A measurement of how effective a dialysis session was. |
| Kidney Stone | A hard mineral deposit formed in the renal pelvis. |
| Lithotripsy | Using sound waves to break up kidney stones. |
| Living Donor | A person who gives a kidney while they are alive. |
| Lupus Nephritis | Kidney inflammation caused by systemic lupus (SLE). |
| Magnesium | A mineral often imbalanced in kidney disease. |
| Maintenance Therapy | Long-term medications to keep a transplant healthy. |
| Membranous Nephropathy | Thickening of the glomerular filtration barrier. A type of glomerulonephritis. |
| Metabolic Acidosis | Too much acid in the blood, common in CKD. |
| Microalbuminuria | Early warning sign of kidney damage in urine. |
| Minimal Change Disease | A common cause of nephrotic syndrome in children. A type of glomerulonephritis. |
| Mycophenolate Mofetil | An anti-metabolite immunosuppressant drug. |
| Nephrectomy | Surgical removal of all or part of a kidney. |
| Nephritis (glomerulo-, GN) | General term for inflammation of the kidney. |
| Nephrocalcinosis | Generalized calcium deposits within the kidney. |
| Nephrologist | A medical doctor specializing in kidney care. |
| Nephron | The tiny functional unit that filters blood. |
| Nephrotoxic | Substances that cause damage to the kidneys. |
| Nephrotic Syndrome | Condition causing heavy protein loss in urine. |
| Oliguria | Low output of urine. |
| PRA | A score indicating how many donors a patient is ‘sensitive’ to. |
| Paired Donation | A multi-way swap of kidneys between donor pairs. |
| Peritoneal Dialysis | Using the abdomen’s lining to clean the blood. |
| Peritonitis | Infection of the abdominal lining, a dialysis risk. |
| Phosphate Binder | Medication to reduce phosphorus levels from food. |
| Plasmapheresis | Removing plasma to clear out harmful antibodies. |
| Podocyte | Specialized cells that form the final filtration barrier. |
| Polyuria | Excessive production of urine. |
| Potassium | Key electrolyte that must be strictly regulated in CKD. |
| Pre-emptive Transplant | Getting a transplant before ever starting dialysis. |
| Proteinuria | Abnormal amounts of protein in the urine. |
| Pyelonephritis | A bacterial infection of the kidney. |
| Rejection | The immune system attacking a new kidney. |
| Renal Artery | The main blood supply to the kidney. |
| Renal Pelvis | The funnel-like part of the kidney leading to the ureter. |
| Renin | Kidney enzyme that regulates blood pressure. |
| Serum Creatinine | Blood test used to measure how well kidneys filter. |
| Tacrolimus | The most common anti-rejection drug used today. |
| Uraemia | Symptoms caused by high waste levels in the blood. |
| Ureter | The tube connecting the kidney to the bladder. |
| Urinalysis | A diagnostic test involving a urine sample. |
| Vasculitis | Inflammation of the blood vessels within the kidney. |
| Waiting list (WL) | The registry of patients needing a deceased donor. |
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