Hi

I have not heard of a direct link between Crohn's and dermotillomania although yes, there seems to be a "brain-gut" connection in many illnesses/disorders IMHO

I am not sure what you mean by "myoplasia"
Did you mean mycoplasma?

Has your brother been checked for food allergies? rashes can develop with those, including gluten intolerance which is prevalent in people with Crohn's
and yes, lack of nutrients due to the absorption being compromised in Crohn's can lead to other health problems, including neurological. Is he getting sufficient B vitamins?

My son has his Crohn's in remission with very careful anti-inflammatory diet and natural sources of antimicrobials, and his OCD related to his Tourette Syndrome is also very stable, again, attributed to careful diet and supplements. He takes no meds.

hope that helps and that you will update re the myoplasia?