RESUMO
Ehrlichiosis and anaplasmosis are tick-borne diseases. Ehrlichia canis and Anaplasma platys infect mainly white cells and platelets, respectively. The main DNA source for PCR is peripheral blood, but the potential of blood cell fractions has not been extensively investigated. This study aims at assessment of whole blood (WB) and blood fractions potential in nested PCR (nPCR) to diagnose canine ehrlichiosis and anaplasmosis. The 16S rRNA gene was amplified in 71.4, 17.8, 31.57, and 30% of the WB, granulocyte (G), mononuclear cells (M), and buffy coat (BC) samples. Compared to the WB, the sensitivity of the PCR was 42.86% for the M, and BC fractions, 21.43% for the G, and 33.33% for the blood clot (C). There was fair agreement between the WB and M, BC and C, and slight with the G. Fair agreement occurred between the nPCR and morulae in the blood smear. One animal was coinfected with A. platys and E. canis. This study provided the first evidence of A. platys infection in dogs in Paraíba, Brazil, and demonstrated that WB is a better DNA source than blood fractions to detect Ehrlichia and Anaplasma by nPCR, probably because of the plasma bacterial concentration following host cell lysis.
Assuntos
Anaplasma/isolamento & purificação , Anaplasmose/diagnóstico , DNA Bacteriano/sangue , Ehrlichia canis/isolamento & purificação , Ehrlichiose/veterinária , Reação em Cadeia da Polimerase/métodos , Anaplasma/genética , Anaplasmose/sangue , Anaplasmose/microbiologia , Animais , Brasil , Tamanho Celular , Coinfecção/sangue , Coinfecção/microbiologia , Coinfecção/veterinária , DNA Bacteriano/genética , Doenças do Cão/sangue , Doenças do Cão/microbiologia , Cães , Ehrlichia canis/genética , Ehrlichiose/sangue , Ehrlichiose/diagnóstico , Ehrlichiose/microbiologia , Genes Bacterianos , Genes de RNAr , Granulócitos/microbiologia , Testes Hematológicos/métodos , Leucócitos Mononucleares/microbiologia , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Sensibilidade e EspecificidadeRESUMO
In Latin America, Lutzomyia longipalpis is the principal vector of Leishmania chagasi, and is associated with the majority of active foci of visceral leishmaniasis. In spite of the fact that this sand fly is spread practically throughout the entire Neotropical Region, its distribution is not uniform due to geographic and environmental barriers. Geographic isolation coupled with reduced flight abilities may contribute to the appearance of cryptic species of Lutzomyia longipalpis, which may differ in their capacity to transmit L. chagasi. In this work, we describe the genetic structuring patterns based on polymorphism analysis of 24 RAPD-PCR loci of 7 natural populations of Lutzomyia longipalpis obtained from Brazil's northeastern region. The estimated degree of genetic differentiation between populations, based on the population subdivision index theta(ST) (0.136), suggests a moderate degree of genetic structuring as a result of geographical isolation and restricted gene flow. Genetic distances were found to be compatible with those found between members of a single species, suggesting a taxonomic uniformity of Lutzomyia longipalpis in the region studied.