title: Serological Diagnosis of Chronic Chagas Disease: Is It Time for a Change?
abstract: Chagas disease has spread to areas that are nonendemic for the disease with human migration. Since no single reference standard test is available, serological diagnosis of chronic Chagas disease requires at least two tests. New-generation techniques have significantly improved the accuracy of Chagas disease diagnosis by the use of a large mixture of recombinant antigens with different detection systems, such as chemiluminescence. The aim of the present study was to assess the overall accuracy of a new-generation kit, the Architect Chagas (cutoff, ≥1 sample relative light units/cutoff value [S/CO]), as a single technique for the diagnosis of chronic Chagas disease. The Architect Chagas showed a sensitivity of 100% (95% confidence interval [CI], 99.5 to 100%) and a specificity of 97.6% (95% CI, 95.2 to 99.9%). Five out of six false-positive serum samples were a consequence of cross-reactivity with Leishmania spp., and all of them achieved results of <5 S/CO. We propose the Architect Chagas as a single technique for screening in blood banks and for routine diagnosis in clinical laboratories. Only gray-zone and positive sera with a result of ≤6 S/CO would need to be confirmed by a second serological assay, thus avoiding false-positive sera and the problem of cross-reactivity with Leishmania species. The application of this proposal would result in important savings in the cost of Chagas disease diagnosis and therefore in the management and control of the disease.
authors.affiliation: Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain.|ISGlobal, Barcelona Centre for International Health Research (CRESIB), Barcelona, Spain.
authors.forename: Alba
authors.initials: A
authors.lastname: Abras
authors.affiliation: Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain.|ISGlobal, Barcelona Centre for International Health Research (CRESIB), Barcelona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Gállego
authors.affiliation: Servei de Microbiologia, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.|Institut d'Investigació Biomèdica Sant Pau (IIB Sant Pau), Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Llovet
authors.affiliation: Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain.|ISGlobal, Barcelona Centre for International Health Research (CRESIB), Barcelona, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Tebar
authors.affiliation: Servei de Microbiologia, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.|Institut d'Investigació Biomèdica Sant Pau (IIB Sant Pau), Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Herrero
authors.affiliation: Servei de Microbiologia, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.|Institut d'Investigació Biomèdica Sant Pau (IIB Sant Pau), Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: Pere
authors.initials: P
authors.lastname: Berenguer
authors.affiliation: Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain.|ISGlobal, Barcelona Centre for International Health Research (CRESIB), Barcelona, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Ballart
authors.affiliation: Unitat de Microbiologia, Hospital General de Granollers, Granollers, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Martí
authors.affiliation: Servei de Microbiologia, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain cmunoz@santpau.cat.|Institut d'Investigació Biomèdica Sant Pau (IIB Sant Pau), Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.|Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Muñoz
mesh_terms: D000328:Adult; D014355:Chagas Disease / Q000175:diagnosis*; D002908:Chronic Disease; D003429:Cross Reactions; D005189:False Positive Reactions; D006801:Humans; D007891:Leishmania / Q000276:immunology; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000379:methods*; D013997:Time Factors
chemical_list: D011933:Reagent Kits, Diagnostic