Licensed from Columbia University Press
Licensed from Columbia University Press
Replacement of a diseased or damaged kidney with one from a living relative or a legally dead donor. The former's tissue type is more likely to match, reducing the chance of rejection; but removal puts the donor at risk, and a kidney from a dead donor is more likely to be available. The new kidney is implanted and its blood vessels and ureter sewn in place. A near-normal life may be resumed within two months, but the drugs that prevent rejection leave the patient vulnerable to infection. Seealso transplant.
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Mass of minerals and organic matter that may form in a kidney. Urine contains many salts in solution, and low fluid volume or high mineral concentration can cause these salts to precipitate and grow, forming stones. Large stones can block urine flow, be a focus for infection, or cause renal colic (painful spasms). They can obstruct the urinary system at various points. Treatment deals with any underlying problem (e.g., infection or obstruction), tries to dissolve stones with drugs or ultrasound (lithotripsy), or removes large ones surgically.
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Partial or complete loss of kidney function. Acute failure causes reduced urine output and blood chemical imbalance, including uremia. Most patients recover within six weeks. Damage to various kidney structures can result from chemical exposure, major blood loss, crush injury, hypertension, severe burns, severe kidney infections, diabetes mellitus, renal artery or urinary tract blockage, and liver diseases. Complications include heart failure, pulmonary edema, and high potassium levels. Chronic failure usually results from long-term kidney diseases. The blood becomes too acidic, bones can lose calcium, and nerves can degenerate. The kidneys can sustain life until they lose about 90percnt of their function. If one is removed, the other increases in size and function to compensate. Failure of both usually requires dialysis or kidney transplant.
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Process of removing blood from a patient with kidney failure, purifying it with a hemodialyzer (artificial kidney), and returning it to the bloodstream. Many substances (including urea and inorganic salts) in the blood pass through a porous membrane in the machine into a sterile solution; particles such as blood cells and proteins are too large to pass. This process controls the acid-base balance of the blood and its content of water and dissolved materials.
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Cross section of a kidney. The kidney is made up of an outermost cortex, a middle medulla, and an elipsis
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