A 25 year old female comes into the family practice clinic complaining of smelly diarrhea. She describes the accompanying abdominal pain as "crampy." She has just returned from a month long service project in Vietnam. She says her stools are bloody and loose.
Labs: Stool sample for an O&P (ova and parasite) examination reveals motile organisms in stool. Cysts in stool sample contain 4 nuclei.
Discussion: The diagnosis of dysentery due to Entamoeba histolytica is made by laboratory analysis of the stool sample. Entamoeba histolytica is a trophozoite. An infection presents with bloody diarrhea and cramping. If the organism invades the portal blood system, liver abscesses may follow. Transmission is by oral-fecal route. Biopsy may demonstrate "flask-shaped" ulcers.
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