Kidneys process blood to sift out waste products and extra water . More than 15 million Americans have some degree of kidney disease . About three-quarters of kidney transplants are between family members , and the rest are among friends and acquaintances , according to the United Network for Organ Sharing , a not-for-profit organization that manages the nation 's transplant system . Comment:
Kidneys process blood to sift out waste products and extra water . More than 15 million Americans have some degree of kidney disease . Comment: