title: Field evaluation of the whole blood immunochromatographic test for rapid bancroftian filariasis diagnosis in the northeast of Brazil.
abstract: This study evaluated the whole blood immunochromatographic card test (ICT card test) in a survey performed in Northeastern Brazil. 625 people were examined by the thick blood film (TBF) and ICT card test. Residents of a non-endemic area were also tested by the whole blood card test and Og4C3. The sensitivity of the ICT card test was 94.7% overall, but lower in females than males, based on the reasonable assumption that TBF is 100% specific. However, since TBF and other methods have unknown sensitivity, the true specificity of the card test is unknown. Nevertheless, it is possible to estimate upper and lower limits for the specificity, and relate it to the prevalence of the disease. In the endemic area, the possible range of the specificity was from 72.4% to 100%. 29.6% of the card tests performed in the non-endemic area exhibited faint lines that were interpreted as positives. Characteristics of the method including high sensitivity, promptness and simplicity justify its use for screening of filariasis. However, detailed information about the correct interpretation in case of extremely faint lines is essential. Further studies designed to consider problems arising from imperfect standards are necessary, as is a sounder diagnostic definition for the card test.
authors.affiliation: Centro de Pesquisas Aggeu Magalh es, Funda o Oswaldo Cruz, Recife, Pernambuco, Brazil. braga@cpqam.fiocruz.br
authors.forename: Cynthia
authors.initials: C
authors.lastname: Braga
authors.forename: Maria Inês
authors.initials: MI
authors.lastname: Dourado
authors.forename: Ricardo Arraes de A
authors.initials: RA
authors.lastname: Ximenes
authors.forename: Luiz
authors.initials: L
authors.lastname: Alves
authors.forename: Fabio
authors.initials: F
authors.lastname: Brayner
authors.forename: Abraham
authors.initials: A
authors.lastname: Rocha
authors.forename: Neal
authors.initials: N
authors.lastname: Alexander
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000947:Antigens, Helminth / Q000097:blood*; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D002845:Chromatography / Q000379:methods; D005260:Female; D005368:Filariasis / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014958:Wuchereria bancrofti / Q000276:immunology*
chemical_list: D000947:Antigens, Helminth; D011933:Reagent Kits, Diagnostic