kidney failure dogs

What are the chances my dog can have liver / kidney disease?
My dog started shaking and ears felt yesterday very hot. He did not stop shaking once the food (Yes to feed regularly.) Is old, 12 years, and has just been to the vet and was given medicine. What are the possibilities that could have liver / kidney? I could not stand having put to sleep. Simply I can not imagine like without him. He is a wonderful dog, "(It is indeed a black Labrador I'm sorry if I only wanted to help, like all other people here, l
The only way whether to take a blood sample taken and analyzed by a pair of enzymes that indicate liver and kidney damage. What did your vet do and what medication is? At 12 is a good chance that might have some liver or kidney damage, however we have special food and medicine to treat these today day, and are often very effective.
Kidney Failure in Dogs