hi doctor ,

i got bloddy mucus SEPERATE FROM STOOLS .i have ibs and went to doctor i have given stool routine test in which mucus(+) and cyst (e.h)(+) NO BLOOD IS FOUND IN TEST .i had colonoscopy on 2013 which was normal i went to doctor YESTARDAY DOCTOR done sigmoidscopy yesday which was normal .he prescribed me T.ciplox and VSL #3 PROBIOTIC .MY QUESTION HERE FROM WHERE THE BLODDY MUCUS COMES FROM (nOTE :ONLY ONCE IT CAME)? TAKING ANTIBIOTIC CAUSE MUCUS IN STOOLS??MY AGE IS 25 FEMALE .NO PAIN WHILE PASSING STOOLS