Free Access
Vet. Res.
Volume 35, Number 1, January-February 2004
Page(s) 141 - 146
How to cite this article Vet. Res. (2004) 141-146
Vet. Res. 35 (2004) 141-146
DOI: 10.1051/vetres:2003038

The relationship between the degree of thrombocytopenia and infection with Ehrlichia canis in an endemic area

Camilo Bullaa, Regina Kiomi Takahiraa, João Pessoa Araújo Jr.b, Luzia AparecidaTrincac, Raimundo Souza Lopesa and Charles Edward Wiedmeyerd

a  Clinical Pathology Laboratory, Departamento de Clínica Veterinária, Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, Botucatu, Brazil
b  Departamento de Microbiologia Imunologia, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, Brazil
c  Departamento de Bioestatística, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, Brazil
d  University of Missouri-Columbia, College of Veterinary Medicine, Department of Veterinary Pathobiology, Columbia, Missouri, USA

(Received 14 March 2003; accepted 14 August 2003)

Abstract - Ehrlichia canis is the causative agent of canine monocytic ehrlichiosis. In order to evaluate platelet counts as a screening test for E. canis in an endemic area, 217 whole blood samples from dogs were divided into three groups: 71 non-thrombocytopenic samples (group A, platelet counts greater than 200 000/mL) and 146 thrombocytopenic samples (less than 200 000/mL). The thrombocytopenic group was further divided into 62 with platelet counts between 100 000-200 000/mL (Group B) and 84 samples with less than 100 000 platelets/mL (Group C). All samples were examined for the presence of a segment of the Ehrlichia canis 16S rRNA gene using a nested polymerase chain reaction. Sixty-seven of the 217 samples (30.9%) were positive for the presence of the E. canis 16S rRNA gene; 53 (63.1%) of the group C samples and 13 (21%) of group B. Only one (1.4%) of the non-thrombocytopenic samples (Group A) was positive. These data support the concept that platelet counts may be a good screening test for canine monocytic ehrlichiosis, and that the magnitude of thrombocytopenia may increase the reliability of diagnosis.

Key words: Ehrlichia canis / thrombocytopenia / platelet counts / screening / PCR

© INRA, EDP Sciences 2004