Department of Pathology, Wildlife Health Sciences, Wildlife Conservation Society, Bronx, NY, USA
Abstract
An 18-yr-old female Arabian camel (Camelus dromedarius) presented with an acute onset of anorexia and cough. Physical examination findings revealed cyanotic mucous membranes. Despite treatment, the animal’s condition continued to deteriorate over the next 3 wk, and euthanasia was elected.
At necropsy, the pericardial sac contained approximately 2 L of serosanguineous fluid. Approximately 30% of the epicardial surface was covered by 0.5–2.0 cm diameter soft, red, pedunculated masses that were most numerous in the atrial and apex regions. Several 0.3–0.5 cm diameter, firm, pink-red, raised masses were present on the visceral pericardial surface. Histologically, the masses were comprised of variably dense fibrous connective tissue cores and branching stalks covered by polygonal to cuboidal cells. The cells were of moderate cellular and nuclear heterogeneity with a moderate to high mitotic index. Many areas contained lymphoplasmacytic infiltrates, hemorrhage, fibrin accumulation, and hemosiderosis. Other significant necropsy findings included ventral subcutaneous edema, ascites, and hepatic changes consistent with chronic-passive congestion.
Gross and histologic findings in this case were consistent with mesothelioma of the pericardium and epicardial surfaces.2,3 The presence of these masses led to an accumulation of pericardial fluid, which likely resulted in heart failure.1 Additional findings of ascites, dependent subcutaneous edema, and chronic passive congestion within the liver are supportive of congestive heart failure as the cause of this camel’s clinical signs. To the best of the author’s knowledge, this is the first reported case of mesothelioma in a camelid.
Literature Cited
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