title: Colonoscopic diagnosis of amebiasis: a case series and systematic review.
abstract: OBJECTIVE
  Nonspecific gastrointestinal symptoms make diagnosis of amebiasis difficult. Certain colonoscopic findings predict amebic colitis while others suggest different diagnoses. We aimed to evaluate the diagnostic capability of colonic evaluation of amebiasis.
  
  
  METHODS
  We retrospectively reviewed data of all amebiasis cases admitted to our institution between 2003 and 2012. Cases were diagnosed by clinical presentation, laboratory examinations, and colonoscopy with biopsy and microscopic examination. Patients were stratified as right-sided colitis and proctosigmoiditis. A systematic review was conducted by searching Medline, Cochrane, EMBASE, and Google Scholar using key words amebiasis, amebic colitis, amebic proctosigmoiditis, colonoscopy, and Entamoeba histolytica. Data were extracted from articles meeting the inclusion criteria. Colonoscopic findings were described and studies were assessed for quality.
  
  
  RESULTS
  The current series included 20 patients (5 male, 15 female, median age 51), 7 with amebic liver abscess and 13 with amebic colitis. Colonoscopic findings of right-sided colitis included aphthae or erosions, ulcers, exudates, or edematous swollen mucosa in cecum, and findings for proctosigmoiditis were edematous swollen mucosa with bloody exudate. In 25 studies, colonoscopic findings of 41 patients (36 male, 5 female, median age 43.39 years) included mainly ulcers in the cecum and rectum, ulcerated mass, and edematous mucosa; and in fewer patients, submucosal invasion suggestive of colon cancer, bleeding ulcers, proctitis, and ulcers with aphthae in rectum.
  
  
  CONCLUSIONS
  Colonic evaluation of suspected amebiasis is of diagnostic value when accompanied by biopsy and microscopic identification of Entamoeba species. Colonoscopic manifestations vary between right-sided colitis and proctosigmoiditis.
authors.affiliation: Division of Colorectal Surgery, Department of Surgery, Chang Gung Memorial Hospital - Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Ko-Chao
authors.initials: KC
authors.lastname: Lee
authors.forename: Chien-Chang
authors.initials: CC
authors.lastname: Lu
authors.forename: Wan-Hsiang
authors.initials: WH
authors.lastname: Hu
authors.forename: Shung-Eing
authors.initials: SE
authors.lastname: Lin
authors.forename: Hong-Hwa
authors.initials: HH
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003113:Colonoscopy; D004404:Dysentery, Amebic / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult