Do I Have To Disclose My Medical Condition To A Potential Employer?

Weighing up the candidate's qualities

An AOL Jobs reader asks:

Your columns are extremely educational and full of information. Thank you from an appreciative reader. I may have missed this, but when applying for a job, is it necessary to disclose any medical conditions? I am a Diabetic Type 1, and use a pump, which could bulge through my clothes, though I take care to avoid that.

I was hired by a high-end jewelry store one month ago, and after working for 10 days, was told by HR, that I was "not a good fit." No other explanation. Needless to say, I was devastated. I am a University graduate with a B.A. and have always worked diligently. Does this business have a right to dismiss me?