What could cause???...women only please!!!? I am a daycare teacher.I have a little girl 22 months in my class who yesterday during a diaper change we noticed a very bad diaper rash. Ok not normal but noted it and went on with our day. Next diaper change though it was not only a rash but noticed a large amount of greenish tinted discharge (coming from privates not rash). Two more diaper changes and still quite a bit of discharge and obvious pain. At first I was thinking yeast infection but I have never seen it greenish colored with a yeast infection before. What could cause this? I think I am more worried about her then her mom...really! She has a doctors appointment already tomorrow so mom said that she will just have the doctor look then. I am concerned that its some sort of infection that shouldnt wait until tomorrow...
Please help ease my mind! 
Ever heard of or dealt with this type of thing?

Summarized question: What would cause a very bad diaper rash and a large amount of greenish tinted discharge (coming from privates, not rash) from 22 months old girl?