Amebiasis

Amebiasis is a common cause of diarrhea in infants in low-income countries. Amebiasis also causes colitis that can present with diarrhea and/or dysentery that can be acute or last more than 1 week. Abdominal tenderness and weight loss are common with amebic colitis.

Amebic liver abscess presents with right upper quadrant pain. May not present with diarrhea, but will usually have a preceding history of diarrhea.

Rare cause of brain abscess.

Most patients will have traveled to or resided in an endemic area in the 12 months preceding presentation.

Diagnosis is confirmed by detection of Entamoeba histolytica antigen or DNA in stool or antibodies against the parasite in serum.

Treatment is with nitroimidazoles (including metronidazole or tinidazole) followed by luminal agents such as paromomycin or diloxanide furoate to prevent relapse.

Amebiasis is caused by the parasite Entamoeba histolytica. It causes diarrhea and colitis. Spread of infection from the intestine can result in liver abscess (via haematogenous dissemination). Extension from liver abscess can lead to pleural and pericardial effusion. Rarely, brain abscess may occur[1]Haque R, Huston CD, Hughes M, et al. Amebiasis. New Engl J Med. 2003;348:1565-1573. http://www.ncbi.nlm.nih.gov/pubmed/12700377?tool=bestpractice.com [2]Petri WA Jr, Singh U. Diagnosis and management of amebiasis. Clin Infect Dis. 1999;29:1117-1125. http://www.ncbi.nlm.nih.gov/pubmed/10524950?tool=bestpractice.com [3]Solaymani-Mohammadi S, Lam M, Zunt JR. Entamoeba histolytica encephalitis diagnosed by polymerase chain reaction of cerebrospinal fluid. Trans R Soc Trop Med Hyg. 2007;101:311-313. http://www.ncbi.nlm.nih.gov/pubmed/16930651?tool=bestpractice.com [4]Snider C, Petri WA Jr. Travel Medicine. In: Rakel RE, ed. Conn's current therapy 2008. 61st ed. New York, NY: W.B. Saunders; 2007.[5]Stanley SL Jr. Amoebiasis. Lancet. 2003;361:1025-1034. http://www.ncbi.nlm.nih.gov/pubmed/12660071?tool=bestpractice.com [6]Diamond LS, Clark CG. A redescription of Entamoeba histolytica Schaudinn, 1903 (amended Walker, 1911) separating it from Entamoeba dispar Brumpt, 1925. J Eukaryot Microbiol. 1993;40:340-344. http://www.ncbi.nlm.nih.gov/pubmed/8508172?tool=bestpractice.com