It seems strange it would come on so suddenly. I wonder if a gall bladder problem with clogged bile ducts could cause the liver damage. One of my dogs had a gallbladder mucocele in her senior year and needed surgery, but unfortunately she got aspiration pneumonia. I think another of my dogs might have had that, before they were sufficiently recognized. They show up on ultrasound, but I believe they do not show up on x-rays.