I believe one applicant was also questioned recently regarding their ability to take care of a medical condition they had (i.e., that they had sufficient finances or access to healthcare). It is very clear what is not acceptable in terms of medical conditions on their website, but it's also important to note that they may question you if a member of the family in the application has a serious or expensive medial problem. I don't know if they can exclude you for that reason, but they may ask about it nonetheless. To see the list of inadmissible medical conditions go to their website.
Cheers
Q