Eczema on butt/crotch on Toddler?

Is it possible to get eczema on the butt/crotch area that could be misdiagnosed as a yeast infection?

My son gets it on his butt cheeks all the time.

does he have it in the creases of his testicles? if so it's probably yeast.
but is it bumpy like eczema?

my son has bad eczema but he's never gotten it down there.