I think it's a very personal choice but one that should be considered very, very carefully. I do not disclose because I know that in my situation it would adversely affect the chances of me being employed. There are a lot of misconceptions associated with this disease -- I really don't think most people understand it unless/until they get it themselves or know someone with it.

IMHO, if you choose to mention it, you are acknowledging that it is an issue. So if you are capable of working and do not need any special accommodation because of your illness, why mention it?

Good luck to you on your job search!