Revision as of 06:40, 4 April 2015 by Arsmd (talk | contribs)


  • Protozoa causing diarrhea.
    • Oocysts are 4-6 µm in diameter and exhibit partial acid-fast staining.
  • Mostly commonly seen in HIV+
  • Most common cause of chronic diarrhea in HIV patients.

Environmental Exposures

  • Swim regularly in pools with insufficient sanitation.
  • Hikers who drink untreated water.
  • Handling infected cattle.

Clinical Presentation

Symptoms usually appear one week after infection which include:

  • watery diarrhea
  • dehydration
  • stomach cramps/pain
  • weight loss
  • fever
  • nausea/vomiting

Differential Diagnosis

Acute diarrhea



Watery Diarrhea

Traveler's Diarrhea


  • Stool acid-staining test
  • Stool Culture


  • If patient non-sick appearing and not immunocompromised, medication often not needed
  • Antiparasitics such as nitazoxanide for immunocompromised patients
  • IV/PO hydration if dehydration present
  • If patient not on HAART therapy, consider contacting HIV/ID for initiating therapies


  • Most of these patient's can be discharged with close PMD/HIV follow up.
  • If patient has electrolyte abnormalities or severely dehydrated consider observation placement vs admission for rehydration therapy

See Also

External Links


  1. Marx et al. “Cholera and Gastroenteritis caused by Noncholera Vibrio Species”. Rosen’s Emergency Medicine 8th edition vol 1 pg 1245-1246.