Kidney, or renal, disease is a common occurrence that affects both dogs and cats. There are basically two different types of renal failure: Acute, which hits suddenly and severely, and chronic, which slowly gets worse over time. Renal failure has many different signs, which may include weight loss, blood in the urine, vomiting periodically, partial anorexia or poor eating, and many other symptoms. A Chemistry Panel and a urinalysis can help determine if your pet's kidneys are functioning properly.