Myelogram changes in animals naturally infected with Leishmania infantum and co-infections
Coinfection, hematology, dog, Ehrlichia spp.
Canine leishmaniasis (CanL) is an important parasitic disease caused by the protozoan Leishmania infantum. The development of clinical signs depends on the immune response of each dog, and the presence of coinfections by vector-borne pathogens. In this study, we evaluated the changes in the myelogram of animals naturally infected with Leishmania infantum and associated coinfections. Bone marrow and blood samples of 37 animals naturally infected with L. infantum, stored in the sample bank of the Parasitology Laboratory of the Universidade Federal do Agreste de Pernambuco, were used. Hematological and biochemical data, research of coinfections by means of the qualitative ELISA test (SNAP 4DX Plus, Idexx laboratory, Westbrook, Maine, USA) and qPCR to determine the L. infantum parasite load were evaluated. Data were evaluated by descriptive statistics to obtain absolute and relative frequencies. A total of 30 of 37 (81.7%) were coinfected by another vector-borne pathogen. Normocytic normochromic anemia and thrombocytopenia were the main findings at hematological examination. On the other hand, the erythroid lineage was within the reference values, which demonstrates ineffective production. A marked increase (four times) in the megakaryocytic series was observed in response to the decrease in these cells in the circulating blood. The presence of macrophages above the reference value was a frequent finding and is related to parasitism by L. infantum in the bone marrow. It is concluded that the presence of co-infections was a factor that accentuated the presence of hematological alterations in the hemogram and myelogram of the animals in the study, indicating a reserved prognosis for these animals.