urate is tied to liver shunt are you near cornell university as dr centers is a good source for liver shunt and if surgery university of tennessee dr tobias will be the cheapest route. So sorry
Did they run bile acid tests ? I would recommend hill's L/D as your dog needs to be on a low protein diet 18% or below. If your dog is not having seizures you may want to just do natural balance vegetarian as that is low in protein and i know a yorkie on this after having stones