
so sorry to hear this. EPI is common in GSDs and more common now than it used to be in Border Collies but not as common in Labs. ( that I am aware of )
The fact your boy didn't respond to treatment sounds like there was more to it than a hereditary EPI, especially causing kidney failure too. Glad you got a diagnosis for the poor boy, it gives a better understanding why he was acting the way he did.
So sorry for your loss
