
Hi Jenny,
It's quite a well known disorder, and can be common in GSD's although I've never had that problem with mine. I don't know a lot about it to be honest....I did have one of my dogs checked for it as he was very thin but thankfully that wasn't the problem.
I really think the best thing is to go with the vets advice to start off with....or get a second opinion from another vet.
This might be a silly question, but have blood tests been taken? As I said, I don't know much about it, but I'm more or less certain that's the only way it can be diagnosed.
Maybe you or your friend could do some research online? Typing in Pancreatic Enzyme deficiency on a search engine will bring up lots of info.
I'm sorry I can't help more, but I'm sure there'll be loads of people along soon that can.
Take care
Lisa
ps, I think treatment is usually an enzyme powder....which is put into food every day...although I may be wrong.