The more fluids your pet consumes, the more toxic waste products it will flush from its body through the fewer health kidney filter units (nephrons) that remain. (2ndchance.info)
This means that in addition to various toxic waste products, the inflamed kidney filters out important proteins (larger molecules) from the blood. (sciencedaily.com)
Kidney disease — lack of kidney filtering ability necessary to keep the level of waste products in you pet's blood within normal limits (60 - 75 % loss). (2ndchance.info)