There have been links to some skin conditions that cause Crohns, im sure if they can go one way it can go another. One that I know of only because my wife was diagnosed with is call Hidradenitis Suppurativa. It is basically tunneling boils that pop up in the armpit, crotch, glutes, face, and on some women under the breasts. We can miss most of the symptoms because of our crohn's ( D, vomiting, nausea ect. ) if you are getting what seems to be boils that can come in 3's please look up Hidradenitis Suppurativa as it is hard to diagnose and also to treat.