title: Double aldehyde stabilisation of erythrocytes in the indirect hemagglutination for echinococcosis.
abstract: Sheep erythrocytes were stabilised with glutaraldehyde tanned and fixed with formalin in the indirect hemagglutination test (IHA-GF) and sensitised with hydatid antigen for the diagnosis of human cystic echinococcosis (CE). The sensitivity of this method was compared to that prepared with fresh tanned cells (IHA-TA) in 278 sera from hydatid patients. The sensitivity of IHA-GF (87.8%) was higher than that of IHA-TA (85.6%), the difference being insignificant. Higher geometric mean titres were obtained by IHA-GF (1:13300) than by IHA-TA (1:11600). The use of two sorts of aldehydes proved to be a satisfactory method, showing high sensitivity, a very good specificity and some advantages. The sensitised cells retained their diagnostic effectiveness for at least 15-18 months when stored at 4 degrees C. The technique is inexpensive and rapid, allowing the testing of a large number of sera. The method reduces the variation of the results and improves the reproducibility of the test. When the minimal diagnostic titre-1:400 is used the specificity of IHA-GF might increase by 2.9% while the sensitivity might decline by only 1.4%. The IHA-GF demonstrated better immunodiagnostic characteristics than enzyme linked immunosorbent assay (ELISA) and Latex agglutination test (LAT). The IHA-GF should be considered as an useful method in the range of classical diagnosis for the serology of CE. The clinical diagnostic potential should be increased by a combination of at least two tests: IHA-GF and ELISA or LAT.
authors.affiliation: Department of Infectious Diseases, Parasitology, Epidemiology and Tropical Medicine, Faculty of Medicine, University of Medicine, Sofia, Bulgaria. bulcoms@internet-bg.net
authors.forename: Todor
authors.initials: T
authors.lastname: Todorov
authors.forename: Kamenna
authors.initials: K
authors.lastname: Vutova
authors.forename: Pencho
authors.initials: P
authors.lastname: Vachkov
authors.forename: Violina
authors.initials: V
authors.lastname: Boeva
authors.forename: Grigor
authors.initials: G
authors.lastname: Mechkov
authors.forename: Stoian
authors.initials: S
authors.lastname: Handjiev
authors.forename: Svetlozar
authors.initials: S
authors.lastname: Donev
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D004443:Echinococcosis / Q000175:diagnosis*; D004446:Echinococcus / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D004912:Erythrocytes / Q000276:immunology*; D005557:Formaldehyde / Q000494:pharmacology*; D005976:Glutaral / Q000494:pharmacology*; D006386:Hemagglutination Tests / Q000379:methods*; D006801:Humans; D007841:Latex Fixation Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012756:Sheep
chemical_list: D000909:Antibodies, Helminth; D005557:Formaldehyde; D005976:Glutaral