Bright yellow baby poop (Warning)

Hi Anyone who encounter bright yellow poop? May baby is having diarrhea for 3 days now na pa test ko na yung poop nya and bacteria daw po naoa check up ko na din po. Tinanong ko doctor if pwd wag muna mag antibiotic kasi kakatapos nya lang because of Ameoba and sabi naman nya pwd namin i try basta wag kakain si baby ng fatty food