What Is The Treatment For Itchy Rashes On The Stomach?

my 6 month old daughter has came out it a prickly rash on stomach and spreading round the back it is itchy as she keeps grabbing it and trying to scratch. its is not chicken pox as she has just got rid of them and was in hospital with a urine infection couple of weeks back and has a reflux of the bladder could this be linked? what could it be if not? thx