Hi Sharon,
as far as is currently known, diabetes is not a cause for Crohn's, which is an auto-immune system malfunction of the small intestine, and/or the large colon. Diabetes is quite different, in that it is caused by the pancreas. Interestingly though, I was diagnosed with pancreatic insufficiency (not diabetes) last September when a CT scan showed an abnormality on the tail of my pancreas.