Effects of therapy on haemostasis in dogs infected with Leishmania infantum, Ehrlichia canis, or both combined

Canine leishmaniosis (CL) and canine ehrlichiosis (CE) are well-recognised infectious diseases in the Mediterranean. In the same area, coinfection with Leishmania and Ehrlichia is very frequently seen too. Haemostatic disorders are common findings in both diseases. Recently, a reduction of the platelet aggregation response in dogs coinfected with Leishmania and Ehrlichia was reported, but data are only available for haemostatic abnormalities during therapy for canine leishmaniosis. No data are available for haemostatic abnormalities during therapy for dogs with canine ehrlichiosis or those coinfected with Leishmania and Ehrlichia. The aim of the present study was to investigate platelet aggregation and secondary haemostasis in dogs naturally infected with L. infantum, E. canis or both combined during specific therapy. Infected animals were divided into three groups of 10 animals: group 1 (CL) treated with a combination of meglumine antimoniate and allopurinol; group 2 (CE) treated with doxycycline monohydrate and group 3 (dogs coinfected with Leishmania and Ehrlichia) treated with a combination of the therapy given to group 1 and 2. A control group of 10 healthy dogs was also studied. Clinical examination and determination of platelet aggregation, coagulation factors and biochemical parameters were undertaken before treatment and after 15, 30 and 60 days. Dogs in groups 1 and 2 showed good clinical improvement two to three weeks after treatment, while all the dogs coinfected with Leishmania and Ehrlichia showed a transient, moderate clinical improvement. All haematological parameters were in the normal range and showed no statistical differences. The efficacy of classic therapies for canine leishmaniosis and ehrlichiosis in improving platelet aggregation is confirmed, but combined treatment in cases of dual infection can lead to a decrease in efficacy. Our data also revealed that, despite a significant improvement, platelet aggregation was still significantly lower than that of healthy dogs.