If you are out of work with a doctor's excuse, regardless of whether you have sick leave or not, or even if you have pointed out on your employer's leave program, whatever, if you have a doctor's excuse for the absence for which they fired you, the company can still fire you, but you may very well be approved for unemployment benefits.
They (unemployment system) tends in all states to look at a documented illness or medical emergency as something unavoidable, not as work related misconduct. Therefore, if your employer fires you for being off work without sick leave according to the company policy, you can probably qualify for unemployment benefits if you have a doctor's statement showing that you were really illor there was some great medical emergency. But in no case is it illegal for the employer to fire you for taking this absence even if you have medical documentation out the wazoo.

