blood in stool but...?

Hmmm, the only two things I can think of for how this could be is a) something wrong with test solution or something along those lines, or b) maybe that little section of stool just didn't have blood in it?

perhaps hemorrhoids dropped a little blood in the stool... especially if bright red in a small amount... occult blood would be unseen blood throughout the stool, which is why you want to get your sample from inside of the stool, or away from any bright red stool... hope this helps.

Guiac tests for OCCULT stool only. So if bright red will not test + for heme. It will test negative. Guiac is hidden blood.

http://www.umm.edu/ency/article/003393.htm

Good to know. I never realized frank blood wouldn't test +.

If your pt had been drinking artificially colored red drinks like Hawiian punch or Hi-C they can have what appears to be frank bright red stools that are NOT blood. It is the dys from the drink.

Could have an anal fissure too.

I find that frank blood is (upon visual inspection of pt) hemrroids. I've rarley found it to be anything else. However, on women check to ensure the blood is from the rectum, I have seen 80 + ladies with lady partsl bleeds a time or 2.