Nephrology  is a specialty of medicine and pediatrics that concerns itself with the study of normal kidney function, kidney problems, the treatment of kidney problems and renal replacement therapy (dialysis and kidney transplantation). Systemic conditions that affect the kidneys (such as diabetes and autoimmune disease) and systemic problems that occur as a result of kidney problems (such as renal osteodystrophy and hypertension) are also studied in nephrology.

The kidneys are vital for life with their complex network of blood vessels and intricate network of tubes and tubules that filter blood of its waste products and excess water. The kidneys maintain the fluid, electrolyte, and acid-base regulation that are altered by several disease conditions as well as drugs and toxins.

Nephrology deals with study of the normal working of the kidneys as well as its diseases. The diseases that come under the scope of nephrology include:

• Glomerular disorders that affect the tiny filtering systems of the kidneys called the glomerulus
• Urine abnormalities such as excess excretion of protein, sugar, blood, casts, crystals etc.
• Tubulointerstitial diseases affecting the tubules in the kidneys
• Renal vascular diseases affecting the blood vessel networks within the kidneys
• Renal failure that can be sudden or acute or long term or chronic
• Kidney and bladder stones
• Kidney infections
• Cancers of the kidneys, bladder, and urethra
• Effects of diseases like diabetes and high blood pressure on kidneys
• Acid base imbalances
• Nephrotic syndrome and nephritis
• Ill effects of drugs and toxins on the kidneys
• Dialysis and its long term complications – dialysis includes hemodialysis as well as peritoneal dialysis
• Autoimmune diseases including autoimmune vasculitis, lupus, etc.
• Polycystic kidneys diseases where large cysts or fluid filled sacs are formed within the kidney impairing its functions – this is a congenital and inherited or genetic condition
• Hydronephrosis

Treatments in nephrology can include medications, blood products, surgical interventions (urology, vascular or surgical procedures), renal replacement therapy (dialysis or kidney transplantation) and plasma exchange. Kidney problems can have significant impact on quality and length of life, and so psychological support, health education and advanced care planning play key roles in nephrology.

Chronic kidney disease is typically managed with treatment of causative conditions (such as diabetes), avoidance of substances toxic to the kidneys (nephrotoxins like radiologic contrast and non-steroidal anti-inflammatory drugs), antihypertensives, diet and weight modification and planning for end-stage kidney failure. Impaired kidney function has systemic effects on the body. An erythropoetin stimulating agent may be required to ensure adequate production of red blood cells, activated vitamin D supplements and phosphate binders may be required to counteract the effects of kidney failure on bone metabolism, and blood volume and electrolyte disturbance may need correction.

Auto-immune and inflammatory kidney disease, such as vasculitis or transplant rejection, may be treated with immunosuppression.

When the kidneys are no longer able to sustain the demands of the body, end-stage kidney failure is said to have occurred. Without renal replacement therapy, death from kidney failure will eventually result. Dialysis is an artificial method of replacing some kidney function to prolong life. Renal transplantation replaces kidney function by inserting into the body a healthier kidney from an organ donor and inducing immunologic tolerance of that organ with immunosuppression. At present, renal transplantation is the most effective treatment for end-stage kidney failure although its world-wide availability is limited by lack of availability of donor organs.

Most kidney conditions are chronic conditions and so long term followup with a nephrologist is usually necessary.