Got turned down for a job because of MTX

[cceg]

I've worked on the bank at our local A&E as a nurse for 2 years.

The other day i went for an interview for the same job i do as a permant post, Today i found out i didnt get it as i failed the medical due to being on MTX 
OK, i know i'm not the best person to work in a department full of ill people due to poor immune system, but i feel very put out.