In my experience, yeast rash truly looks rashy whereas a sore bum from stool just looks red (not raised or splotchy). Yeast rashes also don't seem to respond to regular ointments so if a rash isn't getting better with desitin it's usually a yeast rash in our case.
Mom to two amazing DDs ('07 & '09) and a fur baby.
Gluten free since Nov '11 after non-celiac gluten sensitive diagnosis. Have had great improvement or total elimination of: migraines, bloating/distention, heartburn, cystic acne, canker sores, bleeding gums, eczema on elbows, dry skin and scalp, muscle cramps, PMS, hair loss, heart palpitations, fatigue. I'm amazed.