When I went for interview training before going on my first interviews for Social work jobs, they told you not to disclose personal information on the day of the interview. I would say to be sure that you're picking a job that will not be putting you in a position that you will not force an excess of stress on you because we do need more sick days than most other employees. The bottom line is that once you've secured the job, they can't fire you because of your illness, but they can let you go if they feel that you are not able to perform your job due to absences, etc. Most of the jobs I've had in the past were always accomodating, and the supervisor I have in my career now is a god send! I wouldn't worry too much about it.
P.S. Some of the best advice, which has already been said on here, my mom told me as well when I first started and was nervous about the same thing. If you bust your butt for your employer and show them that no one else can do the job like you, they will be more than accomodating because they will NOT want to let you go! Good luck!