Liver abscess associated with amebiasis is caused by which organism?

Liver abscess associated with amebiasis is caused by which organism?

• A. Entamoeba histolytica
• B. Giardia lamblia
• C. Cryptosporidium parvum
• D. Plasmodium falciparum

Answer: (A)

Entamoeba histolytica is the organism that causes amebic liver abscess. It is acquired by ingesting cysts in contaminated water or food; after intestinal infection, the trophozoites can invade the colonic mucosa and enter the portal circulation, spreading to the liver to form a usually solitary abscess, most often in the right lobe. Clinically you see fever and right upper quadrant pain with hepatomegaly. Serology and imaging help confirm the diagnosis, and the aspirate is typically sterile or shows trophozoites rather than bacteria. Treatment is metronidazole to eradicate tissue parasites, followed by a luminal agent to eradicate cysts and prevent relapse. This differs from other parasites: Giardia lamblia causes giardiasis with diarrhea, Cryptosporidium parvum causes diarrheal illness especially in immunocompromised patients, and Plasmodium falciparum causes malaria with fever and anemia.

Entamoeba histolytica is the organism that causes amebic liver abscess. It is acquired by ingesting cysts in contaminated water or food; after intestinal infection, the trophozoites can invade the colonic mucosa and enter the portal circulation, spreading to the liver to form a usually solitary abscess, most often in the right lobe. Clinically you see fever and right upper quadrant pain with hepatomegaly. Serology and imaging help confirm the diagnosis, and the aspirate is typically sterile or shows trophozoites rather than bacteria. Treatment is metronidazole to eradicate tissue parasites, followed by a luminal agent to eradicate cysts and prevent relapse. This differs from other parasites: Giardia lamblia causes giardiasis with diarrhea, Cryptosporidium parvum causes diarrheal illness especially in immunocompromised patients, and Plasmodium falciparum causes malaria with fever and anemia.