OBJECTIVETo 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.

METHODSAmoebic 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.

RESULTSThe 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.

CONCLUSIONSIt can be concluded that out of the three stains, IHC is the best for identification of E. histolytica trophozoites in tissue sections.

Animals ; Disease Models, Animal ; Entamoeba histolytica ; cytology ; isolation & purification ; Histocytochemistry ; methods ; Immunohistochemistry ; methods ; Liver Abscess, Amebic ; diagnosis ; pathology ; Male ; Mesocricetus ; Microscopy ; Parasitology ; methods ; Staining and Labeling ; methods ; Trophozoites ; cytology