AVALIAÇÃO DE MEDULA ÓSSEA A PERFIL HEMOSTÁTICO DE CÃES NATURALMENTE INFECTADOS POR LEISHMANIA (LEISHMANIA) INFANTUM CHAGASI

Abstract

Visceral leishmaniasis (VL) is considered one of the main neglected parasitic diseases of major public health importance, affecting different species of mammals. Symptomatic dogs have demonstrated bleeding disorders and studies evaluating the integrity of the components involved in coagulation are still insufficient to justify such alterations. The presence of thrombocytopenia is frequently described in infected animals, however, there are few descriptions in veterinary medicine of the use of reticulated platelets to assess medullary regeneration. The aim of this study is to evaluate the hemostatic profile, megakaryocytic lineage and platelet dynamics in dogs naturally infected with Leishmania (Leishmania) infantum chagasi. For the research, biological materials collected from 90 dogs were used and the study was divided into two stages: in the first phase, the analysis of the hemostatic profile in blood samples from 40 animals was carried out. Of these, 06 represented the control group and 34 had CVL. In the second stage, blood and bone marrow samples from 50 dogs were investigated, being 5 healthy and 45 infected by Leishmania (L.) infantum chagasi. The analysis of hemostatic biomarkers in this study did not show important changes that would lead to the development of hemorrhagic conditions in dogs with VL. The absence of liver damage and/or impaired renal function may justify these results. When evaluating bone marrow and thrombocytopoiesis, megakaryocytic morphological changes were observed in 91% of infected dogs and the presence of micromegakaryocytes and hyperlobulations may be associated with more intense medullary parasitic infections in canine VL. The analysis of reticulated platelets showed active thrombocytogenesis to maintain baseline values in some infected dogs and inadequate response to thrombocytopenia due to medullary involvement, verified after the analysis of absolute values, calling attention to the use of this parameter in the face of decreased circulating platelet concentrations.