Concerned co-worker

I have a co- worker that constantly smells like Poop. I don't wanna be mean but she smells up the entire office. It smells something of a polluted fish tank or farty smell. What could this be. I wanna understand. I asked her if she has an illness. She said she has Gallstones and a hernia please explain I would like to help her. She is very a very immaculate person so i don't believe it's from being "dirty" and she is sooooo nice. Please help me understand and help her. What could it be? Tweet