title: Detection of Entamoeba histolytica in experimentally induced amoebic liver abscess: comparison of three staining methods.
abstract: OBJECTIVE
  To compare the efficacy of three different tissue stains, namely haematoxylin and eosin (H&E), periodic-acid Schiff (PAS) and immunohistochemical (IHC) stains for detection of Entamoeba histolytica (E. histolytica) trophozoites in abscessed liver tissues of hamster.
  
  
  METHODS
  Amoebic liver abscess was experimentally induced in a hamster by injecting 1 × 10(6) of axenically cultured virulent E. histolytica trophozoites (HM1-IMSS strain) into the portal vein. After a week post-inoculation, the hamster was sacrificed and the liver tissue sections were stained with H&E, PAS and IHC stains to detect the amoebic trophozoite.
  
  
  RESULTS
  The three stains revealed tissue necrosis and amoebic trophozoites, but with varying clarity. H&E and PAS stained the trophozoites pink and magenta, respectively, however it was difficult to differentiate the stained trophozoites from the macrophages because of their similarity in size and morphology. On the other hand, IHC stain revealed distinct brown appearance of the trophozoites in the infected liver tissues.
  
  
  CONCLUSIONS
  It can be concluded that out of the three stains, IHC is the best for identification of E. histolytica trophozoites in tissue sections.
authors.affiliation: School of Health Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia.
authors.forename: Tan Zi
authors.initials: TZ
authors.lastname: Ning
authors.forename: Wong Weng
authors.initials: WW
authors.lastname: Kin
authors.forename: Shaymoli
authors.initials: S
authors.lastname: Mustafa
authors.forename: Arefuddin
authors.initials: A
authors.lastname: Ahmed
authors.forename: Rahmah
authors.initials: R
authors.lastname: Noordin
authors.forename: Tan Gim
authors.initials: TG
authors.lastname: Cheong
authors.forename: Olivos-Garcia
authors.initials: OG
authors.lastname: Alfonso
authors.forename: Lim Boon
authors.initials: LB
authors.lastname: Huat
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004748:Entamoeba histolytica / Q000166:cytology / Q000302:isolation & purification*; D006651:Histocytochemistry / Q000379:methods; D007150:Immunohistochemistry / Q000379:methods; D008101:Liver Abscess, Amebic / Q000175:diagnosis* / Q000473:pathology*; D008297:Male; D008647:Mesocricetus; D008853:Microscopy; D010274:Parasitology / Q000379:methods*; D013194:Staining and Labeling / Q000379:methods*; D053058:Trophozoites / Q000166:cytology
keywords: Amoebic liver abscess; Entamoeba histolytica; H&E; IHC; PAS; Trophozoite