Entamoeba Histolytica Flashcards
Entamoeba histolytica is a zoonosis. (T/F)
FALSE. It is NOT a zoonosis.
Entamoeba histolytica is the causative agent of what?
Amoebic dysentery or amoebiasis
What is the mode of transmission of Entamoeba histolytica?
Ingestion of cysts in fecal-oral route
Describe the appearance of entamoeba histolytica cysts.
Contain 4 nuclei
Contrast pathogenic vs. nonpathogenic entamoeba histolytica trophozoites.
Pathogenic: 20-40 um.
Apathogenic: 10-20 um.
Describe the life cycle of entamoeba histolytica.
Trophozoites live in lumen of large intestines (pathogenic) whereas nonpathogenic form lives on bacteria in the gut lumen. Occasionally, pathogenic trophozoites enter capillaries.
What are the clinical features of Amoebic dysentery?
- 95% apathogenic
- No fever
- Diarrhea (gradual)
- presence of blood and mucus in liquid feces
- abdominal pain
- flatulence
- tear drop ulcers in gut
How would I diagnose amoebic dysentery caused by entamoeba histolytica?
Direct:
- Cysts in stool
- Trophozoites in RBC indicate invasive form
- ELISA
What are the clinical features of Amoebic Liver Abcess (ALA) caused by Entamoeba histolytica?
- 5%pathogenic
- FEVER
- hepatomegaly
- tender liver
- cysts in liver (80%), brain, skin, lungs, orbit (blindness), spleen and genitals
How would I diagnose Amoebic Liver Abcess (ALA) in patients infected with Entamoeba histolytica?
Direct: aspiration of cysts guided by ultrasound (helps detect number, size, location, condition)
-Indirect: imaging for brain and lung cysts use of X-ray, CT, and MRI
What is the treatment method used for intestinal amoebiasis?
-Metronidazole (Flagyl)
followed by
-Paromomycin (Humatin)
What is the treatment used for Amoebic abscesses?
Chemotherapy with Metronidazole alone may suffice for small cysts but ultrasound guided drainage of large cysts may be necessary.
What would I do in order to prevent Entamoeba Histolytica infections?
- Improved sanitation and safe drinking water
- cooking of vegtables
- stopping use of “night soil”
