Olson Erik J, Wünschmann Arno, Dubey J P
Department of Veterinary Population Medicine/Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.
J Vet Diagn Invest. 2007 Sep;19(5):564-8. doi: 10.1177/104063870701900519.
Protozoal meningoencephalitis is uncommon in raptors. An adult female bald eagle (Haliaeetus leucocephalus) was euthanized after several months of treatment for progressive neurologic signs. The predominant histologic lesion was lymphoplasmacytic and histiocytic meningoencephalitis involving the cerebrum and cerebellum. There was a marked segmental loss of granular cells and Purkinje cells, as well as segmental atrophy of the molecular layer in the cerebellum. Protozoal merozoites and schizonts were observed in the gray matter of the cerebellum. Ultrastructurally, the merozoites were classified as a species of Sarcocystis due to the lack of rhoptries. Immunohistochemistry of the agent revealed a positive reaction for Sarcocystis neurona, while sections were negative for Toxoplasma gondii and Neospora caninum. Sarcocystis sp. infection should be considered as a differential diagnosis in bald eagles with chronic neurologic disease.
原生动物性脑膜脑炎在猛禽中并不常见。一只成年雌性白头海雕（Haliaeetus leucocephalus）在经过数月针对进行性神经症状的治疗后实施了安乐死。主要的组织学病变是累及大脑和小脑的淋巴细胞浆细胞性和组织细胞性脑膜脑炎。小脑颗粒细胞和浦肯野细胞有明显的节段性缺失，以及小脑分子层的节段性萎缩。在小脑灰质中观察到原生动物裂殖子和裂殖体。超微结构上，由于缺乏类锥体，裂殖子被归类为肉孢子虫属的一个物种。对病原体进行免疫组织化学检测显示对犬新孢子虫呈阳性反应，而切片对弓形虫和犬新孢子虫呈阴性。在患有慢性神经疾病的白头海雕中，应考虑肉孢子虫属感染作为鉴别诊断。
