What are the signs of liver disease or kidney failure in a cat/dog?
Kidney failure is symptomized in the early stages by PU/PD = polyuria (excessing urinating) and polydypsia (excessive drinking). The symptoms occur because the kidney has lost its ability to concentrate urine and recycle body fluids. Therefore the body excretes dilute watery urine (not rich golden color with a strong urine smell, but rather clear and relatively odor free.)
In late stages, after the kidney disease progresses from azotemia (high kidney enzymes in the bloodstream indicating toxins are accumulating because the kidney is too weak to filter them out) to uremia (toxins level so high it is triggering the vomiting reflex), the patient becomes anorexic (stops eating) and emesis or vomiting occurs. Dehydration and malnutrition follow unless fluid therapy for diuresis and other kidney treatments are effective.
Kidney disease is largely due to bacterial infection or old age failing kidneys. A bacterial nephritis or glomerulonephritis requires appropriate antibiotic therapy along with fluid therapy.
Liver disease is harder to recognize. Early liver disease often manifests in loss of appetite and activity level. In advanced cases, jaundice or icterus (yellow ears and mucus membranes) becomes apparent.