Which organism causes amebiasis in humans?

Which organism causes amebiasis in humans?

• A. Entamoeba histolytica
• B. Giardia lamblia
• C. Plasmodium falciparum
• D. Toxoplasma gondii

Answer: (A)

Amebiasis is caused by Entamoeba histolytica, a pathogenic intestinal protozoan. It forms cysts in contaminated water or food and is transmitted fecal-oral. In the intestine, the trophozoite form invades the colonic mucosa, causing ulcers, inflammation, and dysentery, and it can spread to the liver to form abscesses if invasive disease occurs. The other organisms listed cause different infections—Giardia lamblia causes giardiasis, Plasmodium falciparum causes malaria, and Toxoplasma gondii causes toxoplasmosis—so Entamoeba histolytica is the organism that causes amebiasis.

Amebiasis is caused by Entamoeba histolytica, a pathogenic intestinal protozoan. It forms cysts in contaminated water or food and is transmitted fecal-oral. In the intestine, the trophozoite form invades the colonic mucosa, causing ulcers, inflammation, and dysentery, and it can spread to the liver to form abscesses if invasive disease occurs. The other organisms listed cause different infections—Giardia lamblia causes giardiasis, Plasmodium falciparum causes malaria, and Toxoplasma gondii causes toxoplasmosis—so Entamoeba histolytica is the organism that causes amebiasis.