I worked 15years w/ hospital and had filed an EEOC complaint because I had been treated differently after revealing to my manager that I needed a certain day off each week for a ADA covered illness. I only worked 4 days per week. I unfortunately made a patient related care mistake with a tpiece. Pt developed pneumothorax and did well after chest tube placed .eventually discharged from hospital. Hospital lied to family and said it was equipment failure when in fact it was an incorrect t-piece. I was fired unexpectantly w/statement of TREND OF MISTAKES
And t-piece. The trend are the EEOC Issue. I am unable to find a job in nursing since 02/14/13

Do you have a lawyer yet? If your case was already filed with the eeoc and then you got fired you might be able to sue for your job back and lost wages.

Have you been accepted as having an EEOC case or have you just started? You can't just say you have an ADA covered illness and need time off each week. You have to have been hired with the illness known to your employer.
If you feel that you have a case because of the wording 'trend of mistakes,' that is another matter. But if the hospital doesn't have a policy guideline for firing, they can fire you for whatever they want, and until the EEOC has decided that you have a case with them, that won't be a basis either.
I agree that you need to hire a lawyer.

Most illness are not ADA covered, and just being sick and needing time off is not protected or covered under ADA.