title: Thick Smear is a Good Substitute for the Thin Smear in Parasitological Confirmation of Canine Visceral Leishmaniasis.
abstract: Although direct examination methods are important for diagnosing leishmaniasis, such methods are often neglected because of their low sensitivity relative to other techniques. Our study aimed to evaluate the performance of bone marrow (BM) thick smears and cytocentrifugation tests as alternatives to direct examination for diagnosing canine visceral leishmaniasis (CVL). Ninety-two dogs exhibiting leishmaniasis seroreactivity were evaluated. The animals were euthanized; and healthy skin, spleen, popliteal lymph node, and BM puncture samples were cultured. BM cultures were used as the reference standard. Of the 92 dogs studied, 85.9% exhibited positive cultures, and Leishmania infantum (synonym Leishmania chagasi) was confirmed in all positive culture cases. The sensitivity rates for cytocentrifugation as well as thin and thick smears were 47.1%, 52.8%, and 77%, respectively. However, no association between the dogs' clinical status and culture or direct examination results was found. To our knowledge, this was the first study to use thick smears and cytocentrifugation for diagnosing CVL. Our results indicate that BM thick smears have a good sensitivity and their use reduces the time required to read slides. Therefore, thick smears can provide a rapid and safe alternative to parasitological confirmation of seroreactive dogs.
authors.affiliation: Laboratório de Pesquisa Clínica e Vigilância em Leishmanioses, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil. cintiaxmello@gmail.com.
authors.forename: Cintia Xavier
authors.initials: CX
authors.lastname: de Mello
authors.affiliation: Laboratório de Pesquisa Clínica em Dermatozoonoses em Animais Domésticos, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
authors.forename: Fabiano Borges
authors.initials: FB
authors.lastname: Figueiredo
authors.affiliation: Laboratório de Pesquisa Clínica em Dermatozoonoses em Animais Domésticos, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
authors.forename: Artur Augusto Velho
authors.initials: AA
authors.lastname: Mendes Júnior
authors.affiliation: Laboratório de Pesquisa Clínica e Vigilância em Leishmanioses, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
authors.forename: Luciana de Freitas Campos
authors.initials: Lde F
authors.lastname: Miranda
authors.affiliation: Laboratório de Epidemiologia Clínica, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
authors.forename: Raquel de Vasconcellos Carvalhaes
authors.initials: Rde V
authors.lastname: de Oliveira
authors.affiliation: Laboratório de Pesquisa Clínica e Vigilância em Leishmanioses, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
authors.forename: Maria de Fátima
authors.initials: Mde F
authors.lastname: Madeira
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000469:parasitology; D004283:Dog Diseases / Q000175:diagnosis* / Q000469:parasitology*; D004285:Dogs / Q000469:parasitology; D018314:Leishmania infantum / Q000302:isolation & purification*; D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000662:veterinary*; D008198:Lymph Nodes / Q000469:parasitology; D012680:Sensitivity and Specificity; D012867:Skin / Q000469:parasitology; D013048:Specimen Handling; D013154:Spleen / Q000469:parasitology