What is your approach to evaluation and management of a patient with Blau Syndrome and GI manifestations?  

Blau syndrome is certainly an unusual diagnosis, as noted by @Cuoghi Edens. I've also only cared for one patient with this. However, it's important to first confirm the diagnosis of Blau. Did the patient have arthritis, dermatitis, and uveitis? Did you get a biopsy that revealed noncaseating granulo...

Which GI manifestations does the patient have? Blau is rare, as you know, and most of us in peds rheum have seen 1 patient at most. Anecdotally, my n=1 did not have any GI issues but was essentially blind and had a very significant rash and boggy synovitis.