Antemortem Diagnosis of Multicentric Lymphoblastic Lymphoma, Lymphoid Leukemia, and Inclusion Body Disease in a Boa Constrictor (Boa constrictor imperator)
A 1.85-kg, 6-yr-old, captive-bred, male boa constrictor (Boa constrictor imperator) was presented for lethargy, anorexia, postural abnormalities, and had an elongated mass on its ventrum, 20 cm distal to the snout. Clinical examination revealed a firm, nonmobile coelomic mass (4 cm × 2 cm) and loss of the righting reflex. Hematology showed a significant increase in white blood cells, lymphocytosis, and anemia. Cytologic examination of the blood smears showed the presence of lymphoid leukemia and eosinophilic intracytoplasmic inclusions consistent with inclusion body disease (IBD). Hyperphosphatemia was suggestive of renal failure. Radiography and ultrasound revealed a soft tissue mass at the level of the thymus proximal to, and distinct from, the heart. Cytology and postmortem histopathology confirmed the presence of a multicentric lymphoblastic lymphoma, lymphoid leukemia, and IBD. It remains unclear whether the neoplasms began their proliferation within the bone marrow or whether leukemia was a feature of disseminated, end-stage lymphoma.Abstract
Cytological diagnosis of IBD, lymphoma, and leukemia in a boa. (A) May Grunwald Giemsa (MGG) –stained blood smear cytology. Increased density of atypical lymphocytes (small arrows). Intracytoplasmic inclusion bodies in erythrocytes (large arrow). Bar = 20 μm. (B) MGG-stained FNA cytology of the mass. High density of monomorphic large round cells (arrowheads) mixed with red blood cells and a few heterophils (large arrow) and lymphocytes (small arrows). Lymphoblastic lymphoma. Bar = 40 μm.
Left lateral radiograph. Diffuse opacity (small arrow), about 3–4 cm long, situated a few centimeters cranial to the cardiac silhouette (large arrow) and causing a ventral deviation of the trachea. The mass was distinctly separate from the heart. T: trachea, M: mass, H: heart, L: lung, Liv: liver.
Stained histologic section of the brain. Neurons and glial cells contain variably sized intracytoplasmic eosinophilic inclusion bodies (arrows). Note the presence of neoplastic cells in the capillaries compatible with lymphoid leukemia (arrowheads). H&E; bar = 60 μm.
