Amebiasis: Difference between revisions

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{{Fever in Traveler DDX}}
{{Fever in Traveler DDX}}
{{Diarrhea DDX}}


==Workup==
==Workup==

Revision as of 18:34, 4 June 2015

Background

  • Fecal oral transmission of Entamoeba histolytica cyst
  • Excystation in intestinal lumen
  • Trophozoites adhere and colonizes large intestine forming new cysts or invade the intestinal mucosa to cause colitis or abscesses
  • Liver abscess-10x more common in men

Clinical Features

  • Asymptomatic vs. dysentery vs. extraintestinal abscesses
  • Intestinal- several weeks of crampy abdominal pain, weight loss, watery or bloody diarrhea
  • Liver abscess-fever, cough, RUQ or epigastric pain, right-sided pleural pain or referred shoulder pain +/- GI upset
    • Hepatomegaly with tenderness over the liver a typical finding
    • Abscess rupture can involve associated peritoneum, pericardium, or pleural cavity
  • Extrahepatic amebic abscesses in the lung, brain, and skin are rare

Differential Diagnosis

Dysentery

  • Infectious- Shigella, Salmonella, Campylobacter, E.Coli.
  • Noninfectious- Inflammatory bowel disease, ischemic colitis, diverticulitis, AV malformation.

Liver abscess

  • Pyogenic liver abscess, necrotic hepatoma, Echinococcal cyst

Fever in traveler

Acute diarrhea

Infectious

Noninfectious

Watery Diarrhea

Traveler's Diarrhea

Workup

  • CBC
  • Chem
  • LFT
  • Stool or abscess microscopy
  • Stool, serum, or abscess fluid antigen
  • Indirect hemagluttination (antibody)

Management

Asymptomatic colonization

  • Paromomycin or Diloxanide

Colitis

  • Flagyl

Liver abscess

  • Flagyl, Tinidazole, Paromomycin, or Diloxanide
  • Consider drainage of abscess if no response to abx in 5 days, abscess >5cm or left lobe involvement

Disposition

  • Home if no complications

Sources

  • Haque R, Huston C, Hughes M, Houpt E, Petri, W. Amebiasis. N Engl J Med 2003; 348:1565-1573
  1. Marx et al. “Cholera and Gastroenteritis caused by Noncholera Vibrio Species”. Rosen’s Emergency Medicine 8th edition vol 1 pg 1245-1246.