title: Sensitivity and specificity of parallel or serial serological testing for detection of canine Leishmania infection.
abstract: In Brazil, human and canine visceral leishmaniasis (CVL) caused by Leishmania infantum has undergone urbanisation since 1980, constituting a public health problem, and serological tests are tools of choice for identifying infected dogs. Until recently, the Brazilian zoonoses control program recommended enzyme-linked immunosorbent assays (ELISA) and indirect immunofluorescence assays (IFA) as the screening and confirmatory methods, respectively, for the detection of canine infection. The purpose of this study was to estimate the accuracy of ELISA and IFA in parallel or serial combinations. The reference standard comprised the results of direct visualisation of parasites in histological sections, immunohistochemical test, or isolation of the parasite in culture. Samples from 98 cases and 1,327 noncases were included. Individually, both tests presented sensitivity of 91.8% and 90.8%, and specificity of 83.4 and 53.4%, for the ELISA and IFA, respectively. When tests were used in parallel combination, sensitivity attained 99.2%, while specificity dropped to 44.8%. When used in serial combination (ELISA followed by IFA), decreased sensitivity (83.3%) and increased specificity (92.5%) were observed. Serial testing approach improved specificity with moderate loss in sensitivity. This strategy could partially fulfill the needs of public health and dog owners for a more accurate diagnosis of CVL.
authors.affiliation: Universidade de Brasília, Brasília, DF, Brasil.
authors.forename: Mauro Maciel de
authors.initials: MM
authors.lastname: Arruda
authors.affiliation: Laboratório de Pesquisa Clínica em Dermatozoonoses em Animais Domésticos, Instituto de Pesquisa Clínica Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.
authors.forename: Fabiano Borges
authors.initials: FB
authors.lastname: Figueiredo
authors.affiliation: Fundação Ezequiel Dias, Belo Horizonte, MG, Brasil.
authors.forename: Andreza Pain
authors.initials: AP
authors.lastname: Marcelino
authors.affiliation: Fundação Ezequiel Dias, Belo Horizonte, MG, Brasil.
authors.forename: José Ronaldo
authors.initials: JR
authors.lastname: Barbosa
authors.affiliation: Instituto de Medicina Social, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
authors.forename: Guilherme Loureiro
authors.initials: GL
authors.lastname: Werneck
authors.affiliation: Universidade de Brasília, Brasília, DF, Brasil.
authors.forename: Elza Ferreira
authors.initials: EF
authors.lastname: Noronha
authors.affiliation: Universidade de Brasília, Brasília, DF, Brasil.
authors.forename: Gustavo Adolfo Sierra
authors.initials: GA
authors.lastname: Romero
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000175:diagnosis*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods / Q000662:veterinary; D006801:Humans; D018314:Leishmania infantum / Q000302:isolation & purification*; D007898:Leishmaniasis, Visceral / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D011634:Public Health / Q000379:methods; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000379:methods / Q000662:veterinary*; D015047:Zoonoses / Q000097:blood / Q000175:diagnosis