HISTORY

A multiple arthropod-borne infection in a 6-month male hound is described. The dog was dewormed and vaccinated two months ago, but ectoparasites prevention was outdated. The dog remained depressed and anorexic for one week and, the previous day, vomited three times. Physical exam showed hyperthermia, pale mucous membranes, petechiae, eversion of third eyelid cartilage, splenomegaly, and there were four ticks in the pinna and cervical region. A tick-borne infection was then suspected and complete blood count, serum biochemistry and ELISA for leishmaniasis was performed. Laboratory analysis revealed regenerative anemia, lymphocytosis, thrombocytopenia, presence of E. platys, granulocytic Ehrlichia spp. (observed in both neutrophils and eosinophils), Hepatozoon canis, and Babesia canis. Serum biochemistry was unremarkable and ELISA was positive. The dog was hospitalized for two days. Fluid therapy and intravenous ranitidine was administered until the dog was able to drink and eat. In addition imidocarb dipropionate, atropine sulphate, and clindamycin were administered. Two weeks later the dog was eating normally and mucous membranes were normal. However, hyperthermia and lymphadenopathy persisted. Lymph node fine needle aspiration cytology revealed reactive lymphadenopathy and confirmed Leishmania infection. Atropine and imidocarb dipropionate were administered again and N-metil-glucosamine and allopurinol were prescribed for leishmaniasis. The owner was advised to update ectoparasite prevention for all his dogs and improve housing conditions to avoid these problems.

DISCUSSION

Clinical cases of combined infections such as Ehrlichia spp., with Babesia canis, or Leishmania infantum, have previously been described. Hematologic abnormalities, hyperthermia, splenomegaly and lymphadenopathy are expected clinical signs associated to babesiosis, ehrlichiosis, and leishmaniasis. Non-specific clinical signs may also appear in hepatozoonosis and ehrlichiosis as well. Renal glomerular disease may be expected due to chronic infection in leishmaniasis, ehrlichiosis, and hepatozoonosis. Hemolysis due to babesiosis may also induce tubular damage. However, the dog did not present azotemia, hyperphosphatemia, hypercalcemia, isosthenuria or clinical signs of renal failure. Therapy for ehrlichiosis, babesiosis and hepatozoonosis is based on imidocarb dipropionate administration. Additional therapy for hepatozoonosis and, potentially, babesiosis, includes clindamycin. Imidocarb dipropionate administration for ehrlichiosis instead of doxycycline was preferred due to the concurrent babesiosis and hepatozoonosis. Combination of doxycycline and clindamycin has not been recommended. Atropine sulphate is administered to avoid adverse effects of imidocarb dipropionate. Therapy for leishmaniasis is based on N-metil glucosamine administration and allopurinol. The poor housing condition and ectoparasite prevention together with the young age could have facilitated the multiple infection. On the other hand, a previous Ehrlichia spp. infection may have impaired immune system and facilitated subsequent infections