Many regular vets don't deal much with liver shunt. A lot of people think it is very common in the breed (it is more likely to occur in them than others) but honestly it is not. This is why I believe in going to specialists for things like this. They are the ones who see these things all of the time. I also do consults with a vet nutrionist for pups like Elliott. I have a few pups in my home on special diets.
If you might be interested in seeing one, here is a link that can help you find a board certified internal med vet:
American College of Veterinary Internal Medicine > Home