Agree... IBD can only be diagnosed through a necropsy. The animal must be dead. They check tissue samples from the brain. liver and various other organs. Blood has nothing to do with it. Even then, the cells conclusive to IBD are found in these organs anyway so it is not a rock solid diagnosis.
Blood work? I would tell your friend to find a new vet as well as a private breeder for snakes.
knew i forgot the brain tissue. *doh*
i knew i wasn't crazy, thanks for clarifying this.