Ascertain whether small bowel vs large bowel<unk> 
Small Bowel<unk>  watery and copious
May have weight loss
Bloating, gas, cramping
Vitamin B12 deficiency if terminal illeum involved
Large Bowel
Frequent small volume, possibly painful stools
Hematochezia - Consider opportunistic pathogens, also consider classic hemorrhagic bacteria (E. coli O157, campylobacter, Shigella, Salmonella, Yersinia)
Weight loss is concerning for infiltrative disease, opportunistic infection
Receptive anal sex - consider local HSV, Gonorrhea, chlamydia, entamoeba
Small Bowel<unk>  watery and copious
May have weight loss
Bloating, gas, cramping
Vitamin B12 deficiency if terminal illeum involved
Large Bowel
Frequent small volume, possibly painful stools
Hematochezia - Consider opportunistic pathogens, also consider classic hemorrhagic bacteria (E. coli O157, campylobacter, Shigella, Salmonella, Yersinia)<unk>  watery and copious
May have weight loss
Bloating, gas, cramping
Vitamin B12 deficiency if terminal illeum involved
Frequent small volume, possibly painful stools
Hematochezia - Consider opportunistic pathogens, also consider classic hemorrhagic bacteria (E. coli O157, campylobacter, Shigella, Salmonella, Yersinia)
HIV diarrhea
Consider routine pathogens causing Diarrhea
CMV colitis
Viruses 
Traveler's diarrhea
Bacteria 
Acute gastroenteritis 
Protozoa 