Diarrheal illness

Main groups

• Acute watery diarrhea

• Secretory diarrhea: If small intestine secretion (usu. 5L/24hrs) > colonic absorption >4L/24hrs you get diarrhea
• Ddx:
  • Cholera: epidemic
  • Enterotoxigenic E. Coli (ETEC): endemic
• Treat with ORS (?reduced osmolality, rice water ?instead of glucose, ?added Zn), all about fluid balance

• Acute bloody diarrhea
  • Often coupled with fever, WBC. Antibiotics typically effective.
    • Shigella
    • Salmonella
    • Amoebic colitis (Entamoeba histolytica)
    • Campylobacter
    • Schistosoma
    • Ulcerative colitis
• Chronic non-bloody diarrhea
  • Differential diagnosis:
    • Intestinal infection
      •protozoa
      •EPEC
      •TB
      •Whipple’s
      •strongyloidiasis
    • Pancreatic dysfunction
    • Lactose intolerance
    • IBD
      •Drug-induced
    • AIDS:
      •protozoa
      •MAC
      •CMV
      •HIV per se (caution!)
      •ARV side effects
    • Lymphoma
    • TB
    • C. difficile
  • Persistant diarrhea-malnutrition syndrome especially challenging
  • Treatment of intestinal protozoa less effective if HIV +ve
  • Tropical sprue
    • Enteropathy and malabsorption of fat, B12, xylose
    • Tropical enteropathy is asymptomatic version, likely environmental reaction
    • Malabsorption causes decrease in growth velocity
• Chronic bloody diarrhea
  • Crohn’s disease
  • Intestinal TB
  • UC
  • Appendix mass
  • Amoebiasis
  • Schistosomiasis