Diagnosis of morphological disorders in the bone marrow in case of feline viral leukemia

Abstract

Feline viral leukemia is a common disease caused by an RNA-containing virus and manifested by various clinical signs. Feline leukemia virus (FeLV) entering the body and further into the lymphatic system and bone marrow leads to a number of disorders that are reflected in the blood picture. Such blood changes include: anemia of various etiologies (immuno-mediated hemolytic anemia, anemia of chronic diseases, aplastic anemia, etc.), leukocytosis or leukopenia, thrombocytopenia, as well as combinations of disorders. The virus is also capable of leading to virus-associated oncopathologies: lymphoma (multicentric, alimentary, mediastinal) and bone marrow changes: acute lymphoblastic leukemia or chronic lymphocytic. The blood pattern changes as a consequence of morphological changes in the bone marrow. Approaches to the treatment of patients depending on the type of hematological changes are different. In this regard, bone marrow was examined in cats infected with viral leukemia and having severe and moderate non-regenerative anemia, as well as bicytopenia and pancytopenia according to a general blood test. A comprehensive methodological approach was used including a general clinical examination, instrumental diagnostics and bone marrow biopsy. This paper discusses a method for selecting and preparing a bone marrow biopsy for morphological examination. The characteristic of morphological findings in the bone marrow associated with the leukemia virus is presented. The study revealed various combinations of hematological disorders in patients with viral leukemia. The data obtained were analyzed and it was revealed that the vast majority of patients with severe hematological disorders also have pronounced pathological changes in the bone marrow. The most common pathologies in the bone marrow in cats with viral leukemia were identified: chronic lymphocytic leukemia, acute leukemia, erythroid germ hypoplasia, bone marrow aplasia.