Canine cutaneous histiocytic tumor with concurrent leishmaniosis in a dog

Background: In veterinary medicine, neoplasms (lymphoma, transmissible venereal tumor, haemangiosarcoma, fibrosarcoma, adrenocortical adenoma, squamous cell carcinoma) with concurrent intracytoplasmic Leishmania amastigotes has been described in dogs, but never in histiocytic disorders. Objective: Describe a case of canine cutaneous histiocytic tumor in a 5-year old intact female English Setter dog with concurrent leishmanias. Methods: CBC, serum biochemical profile, capillary electrophoresis, and ELISA for serodiagnosis of leishmaniasis were performed. Routine cytological Methods: Thirteen cases of cCCL referred to the Veterinary Teaching Hospital “M. Modenato”, between June 2011-2016 were included. The clinical and clinico-pathological findings such as lymph node enlargement, hepatosplenomegaly, lymphocytosis, anemia and thrombocytopenia were used to apply the Binet’s human classification. Conclusion: The veterinary literature classified almost all cCCL in the Binet’s stage C. We established that stages A and B could be identified. Page 77 POSTER ABSTRACTS examination and immunocytochemistry were also carried out on fine-needle aspirates from the cutaneous nodule. Results: Haematology and clinical chemistry abnormalities included hyperproteinemia and hyperglobulinemia. ELISA was moderately positive for Leishmania infantum. Cytologically, the cell population was composed of distinct round cells, ranging from 15 to 40 μm in diameter, with moderate to abundant amount of pale bluish cytoplasm, and round to oval nuclei with fine chromatin. Numerous Leishmania amastigotes were found within the cytoplasm of neoplastic cells. On immunocytochemistry, neoplastic cells were CD1a positive and CD20, CD3 negative. Based on these findings, a diagnosis of a canine cutaneous histiocytic tumor with concurrent leishmaniasis was made. Conclusions: To the authors’ knowledge, this is the first report of a canine cutaneous histiocytic tumor with simultaneous leishmaniosis in dogs.