Misdiagnosis of canine monocytic ehrlichiosis: why do we still risk animal lives?


  • Lizandra Fernandes da Silva Universidade Federal de Jataí, Instituto de Ciências Agrárias, Laboratório de Parasitologia e Análises Clínicas Veterinárias, Jataí – GO, Brazil http://orcid.org/0009-0000-2490-9057
  • Priscila Gomes de Oliveira Universidade Federal de Jataí, Instituto de Ciências Agrárias, Programa de Pós-Graduação em Biociência Animal, Jataí – GO, Brazil http://orcid.org/0000-0002-6151-799X
  • Amanda Noeli da Silva Campos Universidade Federal de Mato Grosso, Faculdade de Medicina Veterinária, Programa de Pós-graduação em Ciências Veterinárias, Cuiabá – MT, Brazil http://orcid.org/0000-0002-6915-2403
  • Vera Lúcia Dias da Silva Universidade Federal de Jataí, Instituto de Ciências Agrárias, Laboratório de Parasitologia e Análises Clínicas Veterinárias, Jataí – GO, Brazil http://orcid.org/0000-0001-6964-3643
  • Klaus Casaro Saturnino Universidade Federal de Jataí, Instituto de Ciências Agrárias, Programa de Pós-Graduação em Biociência Animal, Jataí – GO, Brazil http://orcid.org/0000-0001-8493-8669
  • Ísis Assis Braga Universidade Federal de Jataí, Instituto de Ciências Agrárias, Laboratório de Parasitologia e Análises Clínicas Veterinárias, Jataí – GO, Brazil http://orcid.org/0000-0001-5713-4833
  • Daniel Moura de Aguiar Universidade Federal de Mato Grosso, Faculdade de Medicina Veterinária, Programa de Pós-graduação em Ciências Veterinárias, Cuiabá – MT, Brazil http://orcid.org/0000-0001-8631-522X
  • Dirceu Guilherme de Souza Ramos Universidade Federal de Jataí, Instituto de Ciências Agrárias, Laboratório de Parasitologia e Análises Clínicas Veterinárias, Jataí – GO, Brazil http://orcid.org/0000-0001-9603-6638
  • Cecília Nunes Moreira Universidade Federal de Jataí, Instituto de Ciências Agrárias, Programa de Pós-Graduação em Biociência Animal, Jataí – GO, Brazil http://orcid.org/0000-0001-7629-3290




Diagnosis, Ehrlichia canis, False-positive, Treatment


Canine Monocytic Ehrlichiosis (CME) is a tick-borne disease caused by Ehrlichia canis that manifests as acute, chronic, or subclinical forms without specific clinical symptoms. This disease is diagnosed using clinical and laboratory findings (blood smears, molecular techniques, and serology). This study aimed to demonstrate the occurrence of false-positive results for Ehrlichia spp. in veterinary clinical practice. Seventy dogs with positive blood smears before treatment for Ehrlichia spp. subjected to doxycycline and imidazole treatment were analyzed using hematological examination, polymerase chain reaction (PCR), and indirect immunofluorescence assay. PCR analysis identified no samples positive for E. canis according to PCR analysis, while serological techniques showed a frequency of 51.4% in dogs with antibodies (IgG) against Ehrlichia spp. There was a correlation between hyperproteinemia and titers > 10,240. Nonspecific changes occurred in 24.3% (17/70) of the patients with CME, such as anemia, leukopenia, and thrombocytopenia. The results indicated that the blood count and blood smear analysis were insufficient for diagnosis and that positive serological results associated with hematological changes suggestive of ehrlichiosis in dogs can be incorrectly assigned by a veterinarian, putting animals at risk.


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How to Cite

Silva, L. F. da, Oliveira, P. G. de, Campos, A. N. da S., Silva, V. L. D. da, Saturnino, K. C., Braga, Ísis A., Aguiar, D. M. de, Ramos, D. G. de S., & Moreira, C. N. (2023). Misdiagnosis of canine monocytic ehrlichiosis: why do we still risk animal lives?. Brazilian Journal of Veterinary Research and Animal Science, 60, e213508. https://doi.org/10.11606/issn.1678-4456.bjvras.2023.213508




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