title: Multisite clinical evaluation of a rapid test for Entamoeba histolytica in stool.
abstract: Rapid point-of-care detection of enteric protozoa in diarrheal stool is desirable in clinical and research settings to efficiently determine the etiology of diarrhea. We analyzed the ability of the third-generation E. histolytica Quik Chek assay developed by Techlab to detect amebic antigens in fecal samples collected from independent study populations in South Africa and Bangladesh. We compared the performance of this recently released rapid test to that of the commercially available ProSpecT Entamoeba histolytica microplate assay from Remel and the E. histolytica II enzyme-linked immunosorbent assay (ELISA) from Techlab, using real-time and nested-PCR for Entamoeba species to resolve any discrepant results. After discrepant resolution, The E. histolytica Quik Chek assay exhibited sensitivity and specificity compared to the E. histolytica II ELISA of 98.0% (95% confidence interval [CI], 92.9% to 99.8%) and 100% (95% CI, 99.0% to 100%), respectively. Compared to the ProSpecT microplate assay, the E. histolytica Quik Chek (Quik Chek) assay exhibited 97.0% sensitivity (95% CI, 91.5% to 99.4%) and 100% specificity (95% CI, 99.0% to 100%). Our results indicate that the Quik Chek is a robust assay for the specific detection of E. histolytica trophozoites in unfixed frozen clinical stool samples.
authors.affiliation: Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, USA.
authors.forename: Hans P
authors.initials: HP
authors.lastname: Verkerke
authors.affiliation: Techlab, Blacksburg, Virginia, USA.
authors.forename: Blake
authors.initials: B
authors.lastname: Hanbury
authors.affiliation: Parasitology, International Center for Diarrheal Disease Research, Dhaka, Bangladesh.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Siddique
authors.affiliation: University of Venda, Limpopo Province, South Africa.
authors.forename: Amidou
authors.initials: A
authors.lastname: Samie
authors.affiliation: Parasitology, International Center for Diarrheal Disease Research, Dhaka, Bangladesh.
authors.forename: Rashidul
authors.initials: R
authors.lastname: Haque
authors.affiliation: Techlab, Blacksburg, Virginia, USA.
authors.forename: Joel
authors.initials: J
authors.lastname: Herbein
authors.affiliation: Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, USA wap3g@cms.mail.virginia.edu.
authors.forename: William A
authors.initials: WA
authors.lastname: Petri
mesh_terms: D000293:Adolescent; D000953:Antigens, Protozoan / Q000032:analysis*; D001459:Bangladesh; D002648:Child; D002675:Child, Preschool; D003955:Diagnostic Tests, Routine / Q000379:methods*; D004748:Entamoeba histolytica / Q000302:isolation & purification*; D004749:Entamoebiasis / Q000175:diagnosis*; D005243:Feces / Q000469:parasitology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D019095:Point-of-Care Systems; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013019:South Africa; D013997:Time Factors
chemical_list: D000953:Antigens, Protozoan