Mental Illness does not exist

The shrinks told you that so they can sell their services to you.

If it has a biological cause, then it is not mental but neurological. There could be a reason why it would correlate with pedophilia if pedophilia were found to have a clear biological basis, much as how lead or mercury intake lead to neurological, pseudo-mental, illnesses. However, since it hasn't been proven that pedophilia has a biological basis, [Disclaimer: I think it does.] it is one step too many to jump to finding neurological correlates.

If it does not have a biological cause, it's not an illness, only a socially undesired conduct, whether they put you in because you think you're Jesus, you refuse to sleep inside a room, you believe in aliens visiting us, or you question the wisdom and integrity of the Soviet system.