Intravascular Leukostasis and Systemic Aspergillosis in a Horse With Subleukemic Acute Myelomonocytic Leukemia

Abstract

Leukemia is a neoplastic disease of one or more of the cell types of the hemopoietic system and is rarely diagnosed in the horse. This report describes a case of subleukemic acute myelomonocytic leukemia in an 1 1-year-old gelding. Preliminary cytological diagnosis was supported by two types of laboratory investigations. Cytochemical characterization of blood and bone marrow neoplastic cells was consistent with a myelomonocytic origin. Neoplastic blast cells in peripheral blood were labeled by monoclonal anti-bodies specific for cell surface molecules of horse granulo-cytes, but they were not labeled by antibodies to T-or B-lymphocytes or macrophages. Treatment was attempted eukemia is a neoplastic disease involving one or more of

Immunophenotypic Classification of Leukemia in 3 Horses

“…10 On flow cytometric analysis, these cells were negative for T cell, B cell, and macrophage markers, but stained positively with the granulocyte marker, the WS25 antibody. 30 In addition, these cells expressed EqWC2 but not EqWC1.…”

“…Cytochemical staining for cell products enhances identification of the cell lineage. [2][3][4][5][6][7][8]10,[23][24][25][26][27] A series of cytochemical stains, including Sudan black B, peroxidase, periodic acid-Schiff, alkaline phosphatase, acid phosphatase, chloracetate esterase, nonspecific esterases, and platelet glycoproteins, have been used to stain cells in peripheral blood and bone marrow. 28 The cell type may be identified based on the pattern obtained with this battery of stains.…”

Acute B-lymphoid leukemia in a mare: a case report

“…Intravascular leukostasis, aggregation of leukemic cells in blood vessels, is seen when the WBC concentration is greater than 200 × 10 9 /l or when blast cells are greater than 40% of the WBC (McKee and Collins, 1974). It has been described as the cause of death in a horse with acute myelomonocytic leukemia (Buechner-Maxwell et al, 1994). Both intravital conditions were present in this case, but the presence of intravascular leukostasis was not found post mortem in this mare.…”

Haematology and Clinical Biochemistry Findings Associated with Equine Diseases - a Review

“…Mycotic pneumonia is a respiratory disease of horses characterized by fever, tachycardia, weight loss, nasal discharge, laminitis and uveitis (Blue et al, 1987;Buechner-Maxwell et al, 1994). The disease is caused by Aspergillus spp.…”

“…Mycotic pneumonia affects horses on glucocorticoid treatment and those with an overwhelming challenge by Aspergillus species (Ruoff, 1988). It is also seen in cases of hypercortisolemia associated with pituitary adenomas, ulcerative enterocolitis and myeloproliferative neoplasia (King, 1993;Pace et al, 1994;Buechner-Maxwell et al, 1994). The clinical signs of the disease include fever, lethargy, inappetence, slight tachypnea, increased respiratory rate, moderate increased bronchoalveolar sounds, recumbency and death.…”