Intracranial ependymoma and secondary hydrocephalus: a rare case report in a Camel (Camelus bactrianus)

Intracranial ependymomas are rare neuroepithelial tumors that arise from the ependymal lining of the ventricular system. Although sporadically reported in domestic species, primary brain tumors remain exceptionally rare in Old and New World camelids. This report describes the clinico-pathological characteristics of an intracranial ependymoma associated with secondary hydrocephalus in an adult female camel (Camelus bactrianus). The animal presented with progressive neurological signs, including a unilateral circling gait and ataxia. Computed tomography (CT) revealed asymmetric enlargement of the lateral ventricles with a mass effect. Post-mortem findings were characterized by a well-circumscribed, expansive intraventricular mass obstructing the left lateral ventricle and causing ventricular dilatation. Histologically, the neoplasm consisted of polygonal cells arranged in layers and perivascular pseudorosettes, with occasional true rosettes. It contained multifocal areas of necrosis, affecting approximately 25% of the mass, and was surrounded by multinucleated giant cells. Immunohistochemically, tumor cells showed strong and diffuse cytoplasmic positivity for vimentin, while glial fibrillary acidic protein (GFAP) expression was sparse and showed scattered cytoplasmic positivity in neoplastic cells. These findings confirmed the diagnosis of ependymoma. To the authors' knowledge, this is the first reported case of intracranial ependymoma in a Bactrian camel.