HEMATOLOGICAL OBSERVATIONS IN THE BLOOD AND BONE MARROW OF DOGS NATURALLY INFECTED BY Ehrlichia spp. AND Anaplasma spp.

Abstract

This study aimed to analyze the hematological and cytomorphological findings in the peripheral blood and bone marrow of dogs infected with Ehrlichia spp. and Anaplasma spp. Forty-four dogs with clinically suspected hemoparasitosis, belonging to different breeds, ages, and both sexes, underwent serological examination by SNAP Assay, hematological analysis, and myelogram. Among them, 63.6% (28/44) tested serologically positive; among the serologically positive dogs, 57.1% (16/28) tested positive for Ehrlichia spp., 21.4% (6/28) for Anaplasma spp., and 21.4% (6/28) were coinfected. Thrombocytopenia was the most frequent hematologic alteration in dogs positive for Ehrlichia spp., present in 93.7% (15/16) (p=0.015) of the infected animals, while macrocytic and hypochromic anemia were observed in 66.7% (4/6) (p=0.010) of the animals infected with Anaplasma spp. In the myelogram, 62.5% (10/16, p=0.005) and 75.0% (12/16, p=0,044) of the animals positive for Ehrlichia spp. presented with bone marrow hypoplasia and decrease in the myeloid: erythroid (M:E) ratio, respectively. Hyperplasia of the erythroid series was observed in 50.0% (3/6) (p=0.022) of the animals positive for Anaplasma spp. No significant association was observed between the hematological alterations and the coinfection group (p>0.05). On the basis of these hematological observations, it can be inferred that the aforementioned laboratory examinations could be employed for the characterization and confirmative diagnosis of hemoparasitosis in dogs. 
Keywords: hematological analysis, hemoparasitosis, immunodiagnostic, myelogram.