Question

What is the etiological agent of amebiasis? How is it transmitted and what are the typical manifestations of the disease?

Answer 1

ETILOGICAL AGENT OF AMEBIASIS

Amebiasis is an infectious disease caused by the anaerobic protozoan Entamoeba histolytica.  Entamoeba histolytica is very common in tropical and subtropical regions and affects more than 50 million people worldwide. Men and especially immunocompromised individuals have a higher risk of developing liver abscesses.

MODE OF TRANSMISSION

Transmission usually occurs through the fecal-oral route (e.g contaminated drinking water) when traveling in an endemic region. Depending on its manifestation, amebiasis is termed either intestinal or extraintestinal. After an incubation period of one to four weeks, symptoms such as loose stools with mucus and fresh blood in combination with painful defecation develop. In extraintestinal amebiasis, amebic abscesses (mostly a single liver abscess in the right lobe of the liver) may form, resulting in pain as well as a feeling of pressure in the right upper quadrant (RUQ).

Important diagnostic steps include stool analysis and liver ultrasound to assess extraintestinal amebiasis. Treatment consists of paromomycin to destroy intestinal amebae and metronidazole for invasive disease. Image-guided needle aspiration may be indicated in cases involving complicated liver abscesses.