Infectious Disease Compendium

Entamoeba histolytica


Protozoa and includes E. coli (that's E. coli, not E. coli. Get the difference?), E. gingivalis, E. hartmanni, E. histolytica, E. hartmanni, E. polecki.

Epidemiologic Risks

Eating the cysts aka fecal-oral. Blech. It is a sexually transmitted disease (PubMed).


E. histolytica: bloody diarrhea and amoebic liver abscess which can rupture into the pleura, pericardium and peritoneum.

Severe disease can mimic appendicitis, ischemic bowel disease, tuberculosis and malignancy (PubMed). Travel history is can be so important.


Cyst Passers: paromomycin 30 mg/kg/d in 3 divided doses for 5-10 d OR tetracycline 250 mg qid for 10 d, THEN iodoquinol 650 mg tid for 20 d OR metronidazole 750 mg tid for 10 days.

Invasive colitis: metronidazole 750 mg tid for 5-10 days PLUS paromomycin.

Liver Abscess: metronidazole 750 mg tid for 5-10 d PLUS paromomycin.


Large abscess in the liver may benefit from percutaneous drainage.

In Japan, HIV patients seropostive for E. histolytica had an increased risk of developing invasive disease (PubMed).