Entamoeba histolytica infection is classified as what type of infection?

• A. Bacterial infection
• B. Protozoal infection
• C. Viral infection
• D. Fungal infection

Answer: (B)

Entamoeba histolytica infection is a protozoal infection. Entamoeba histolytica is a protozoan parasite, a single-celled eukaryote. Protozoa are a different category from bacteria, viruses, and fungi. The organism exists as cysts in contaminated water or food and as invasive trophozoites in the colon, where it can destroy mucosa and cause dysentery; it can spread through the bloodstream to the liver, causing abscesses. Because it is a protozoan, diagnostic tests look for protozoan organisms in stool or antibodies, and treatment uses anti-protozoal medications such as metronidazole followed by a luminal agent. In short, the infection is protozoal, not bacterial, viral, or fungal.