Is one who removes imaginary impurities sinful for believing the madhy and nosebleed are not impure due to obsessive-compulsive disorder?

A person afflicted with obsessive doubts (waswas) should not pay attention to them. If he is certain of the presence of prostatic fluid (madhi) or blood, both of which are impure (najis) by scholarly consensus, then he must purify them. Otherwise, he would be sinful, and his prayer would be invalid, as the purity of one's clothes, body, and place of prayer is a condition for the validity of prayer. As for mere doubt, it should not be heeded.