Aspiration cytology of popliteal lymph nodes as a diagnostic method of canine visceral leishmaniasis (CVL) in areas of socioeconomic vulnerability

Antônio Carlos Severino Neto,Reiner Silveira De Moraes,Priscila Gomes De Oliveira,Luiz Antônio De Jesus Sousa,Dirceu Guilherme De Sousa Ramos,Thâmara Rossi Martins Da Silva,Gabriel Lopes Germano

doi:10.33448/rsd-v10i5.14457

Antônio Carlos Severino Neto, Reiner Silveira De Moraes + Show 5 more

Open Access

https://doi.org/10.33448/rsd-v10i5.14457

Copy DOI

Abstract

Leishmaniasis is an endemic disease in Goiás and has high lethality owing to its high zoonotic potential. In dogs, the disease manifests based on the parasitic load, with clinical presentation as the starting for diagnosis. Diagnostic methods are used to confirm the disease, with emphasis on lymph node aspiration cytology, which is a high-standard technique owing to its low cost, ease of performance, and high specificity. The aim of this study was to demonstrate aspiration lymph node cytology as a diagnostic method for canine visceral leishmaniasis (CVL) in areas containing low-income populations with poor access to molecular tests. Three dogs with suspected CVL were studied at Veterinary Hospital of the Federal University of Jataí, in which popliteal lymph node cytology was performed, owing to easy access, and screening and confirmatory examinations were undertaken by the Central Public Health Laboratory. The results showed three positive animals in the cytology and only one positive in the other tests; therefore, there was the possibility of the occurrence of false negatives in serological tests given the time required for seroconversion. Thus, cytology is an important diagnostic technique in areas where molecular tests are not available.

Highlights

Leishmaniasis is a disease with zoonotic potential, which is caused by an obligatory intracellular protozoan belonging to the genus Leishmania (Limeira et al, 2019)
Serology (SNAP Leishmania IDEXX test) was performed for canine visceral leishmaniasis (VL) (CVL), with the animal being the reagent, and cytology of the right and left popliteal lymph nodes, where amastigote forms of Leishmania spp. were distributed throughout the macrophage cytoplasm and extracellular amastigotes were found close to the lymphocytic cells in both lymph nodes (Figure 2)
Cytology of the left popliteal lymph node showing the amastigote forms of Leishmania spp. in macrophage cytoplasm and the extracellular amastigote forms of Leishmania spp

Summary

Introduction

Leishmaniasis is a disease with zoonotic potential, which is caused by an obligatory intracellular protozoan belonging to the genus Leishmania (Limeira et al, 2019). Owing to its clinical complexity, leishmaniasis is viewed as a serious public health problem and is the most important emerging disease in Latin America (Barros et al, 2019), especially in countries that have tropical and subtropical climates (Benassi et al, 2018). According to Andrade-Filho et al (2017), Brazil is a country with a high incidence of visceral leishmaniasis (VL) and in the Northeast, Southeast, and Midwest regions the disease is endemic (Escobar et al, 2019). The state of Goiás, located in the central-western region of Brazil, is endemic for the disease, with reported cases of human VL (HVL) and canine VL (CVL) in several municipalities (Goiás, 2017). The lethality rate of the disease in the state is high and between 2007 and 2015, out of 304 positive cases, there were 34 deaths, a lethality rate of approximately 11%. In 2018, the lethality rate was approximately 7.5% out of 53 cases diagnosed as positive (Goiás, 2019)

Objectives

Methods

Results

Discussion

Conclusion