title: Performance of a rapid diagnostic test for the detection of visceral leishmaniasis in a large urban setting.
abstract: BACKGROUND
  Rapid diagnostic tests (RDTs) may improve the early detection of visceral leishmaniasis (VL), but their real-world performance requires additional study. Therefore, we evaluated the performance of an rK39-based RDT (Kalazar Detect™) for the detection of VL in an endemic, large urban area.
  
  
  METHODS
  Data were collected from a registry of rK39 RDT performed at 11 emergency care units in Belo Horizonte, Brazil, and from a national database of reportable communicable diseases of the Sistema de Informação de Agravos de Notificação (SINAN).
  
  
  RESULTS
  The rapid rK39 test was performed in 476 patients, with 114 (23.9%) positive results. The analysis of rK39 RDT performance was based on 381 (80%) cases reported to the SINAN database, of which 145 (38.1%) were confirmed cases. Estimates for sensitivity and specificity were 72.4% (95% CI: 64.6-79%) and 99.6% (95%CI: 97.6-99.9%), respectively. Positive and negative predictive values were estimated at 99.1% (95%CI: 94.9-99.8%) and 85.5% (95%CI: 80.8-89.1%), respectively. In addition, close agreement between the rK39 RDT and indirect immunofluorescence was observed.
  
  
  CONCLUSIONS
  In summary, the rK39 RDT showed a high specificity but only moderate sensitivity. In endemic areas for VL, treatment may be considered in cases with clinical manifestations and a positive rK39 RDT, but those with a negative test should be subjected to further investigation.
authors.affiliation: Secretaria Municipal de Saúde, Prefeitura Municipal, Belo HorizonteMG.
authors.forename: Alexandre Sampaio
authors.initials: AS
authors.lastname: Moura
authors.forename: Helen Maria Ramos de Oliveira
authors.initials: HM
authors.lastname: Lopes
authors.forename: Maria Vitória Assumpção
authors.initials: MV
authors.lastname: Mourão
authors.forename: Maria Helena Franco
authors.initials: MH
authors.lastname: Morais
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D002846:Chromatography, Affinity; D005260:Female; D006801:Humans; D007223:Infant; D007893:Leishmania donovani / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015800:Protozoan Proteins; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014504:Urban Health; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D015800:Protozoan Proteins; D011933:Reagent Kits, Diagnostic; C079253:K39 antigen, Leishmania