Amebiasis (amebic dysentery)

Introduction. 

Amebiasis is an intestinal infection by the ameboid protozoan Entameba histolytica (meaning 'tissue destruction'). Transmission is through oral-fecal route (contaminated water) in areas with poor sanitation. Water filtration and chlorination are effective control measures. Entamoeba is an invasive protozoan which can spread to other organs (liver, brain) and cause abscesses.

Summary

• Cause: Entamoeba histolytica
• Microscopy: Amoeba (protozoan); cysts often seen in stool
• Transmission: Oral-fecal (contaminated water)
• Life cycle
• Symptoms: Pain, cramping, colitis, bloody stool
• Complications: Abscesses - spread to other organs (brain, liver) esp. in AIDS
• Pathogenesis: Invasion and damage of intestinal lining due to cytotoxins (flask-shaped ulcer)
• Treatment: Metronidazole