I don't really understand the reason for your question. Are you personally suffering from a condition that can't seem to be diagnosed, or are your interests based on something else?

I have been living with a physical condition for nearly five years now without a diagnosis, and know several others here who are in the same predicament. If you have a condition yourself, it would help a lot if you'd post the sypmtoms and the story behind them. It might be a long shot, but you never know until you try!

Best wishes to you,

Idealist