title: Comparison of the Flotac-400 dual technique and the formalin-ether concentration technique for diagnosis of human intestinal protozoon infection.
abstract: There is a need for accurate diagnosis of intestinal parasite infections in humans, but currently available copromicroscopic techniques have shortcomings, such as low sensitivity. We compared the diagnostic accuracy of a further modified version of the recently developed Flotac technique with that of the widely used formalin-ether concentration technique (FECT) for the detection of intestinal protozoa in human stool samples. Formaldehyde-preserved stool samples from 108 individuals in Côte d'Ivoire were subjected to the Flotac-400 dual technique, using two different flotation solutions (FS), and to the FECT. Stool samples were examined according to computer-generated random lists by an experienced laboratory technician blinded for the results of each method. Both methods detected the same eight intestinal protozoon species. While the Flotac-400 dual technique (results from both FS combined) found higher prevalences of Entamoeba coli (77.8% versus 71.3%, P < 0.001), Blastocystis hominis (20.4% versus 13.0%, P = 0.458), and Giardia intestinalis (8.3% versus 6.5%, P < 0.001), the FECT detected higher prevalences of Entamoeba histolytica/Entamoeba dispar (27.8% versus 20.4%, P = 0.019) and four species of nonpathogenic intestinal protozoa. The diagnostic agreement between the two methods differed considerably depending on the intestinal protozoon investigated (Cohen's kappa measures; range, 0.01 to 0.46). Our study confirmed that the Flotac-400 dual technique can be utilized for the diagnosis of intestinal protozoon infections in humans. Since Flotac is a sensitive technique for the detection of soil-transmitted helminths and Schistosoma mansoni, it might become a viable copromicroscopic technique for the concurrent diagnosis of helminths and intestinal protozoon infections.
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.
authors.forename: Sören L
authors.initials: SL
authors.lastname: Becker
authors.forename: Laurent K
authors.initials: LK
authors.lastname: Lohourignon
authors.forename: Benjamin
authors.initials: B
authors.lastname: Speich
authors.forename: Laura
authors.initials: L
authors.lastname: Rinaldi
authors.forename: Stefanie
authors.initials: S
authors.lastname: Knopp
authors.forename: Eliézer K
authors.initials: EK
authors.lastname: N'goran
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Cringoli
authors.forename: Jürg
authors.initials: J
authors.lastname: Utzinger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002648:Child; D002675:Child, Preschool; D019411:Clinical Laboratory Techniques / Q000379:methods*; D005243:Feces / Q000469:parasitology; D005260:Female; D006801:Humans; D007223:Infant; D007411:Intestinal Diseases, Parasitic / Q000175:diagnosis* / Q000469:parasitology; D008297:Male; D008853:Microscopy / Q000379:methods*; D008875:Middle Aged; D010274:Parasitology / Q000379:methods*; D011528:Protozoan Infections / Q000175:diagnosis* / Q000469:parasitology; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D055815:Young Adult