California Animal Health and Food Safety (CAHFS) Laboratory System, University of California Davis, West Health Sciences Drive, Davis, CA 95616, USA.
Vet Parasitol. 2012 May 25;186(3-4):497-502. doi: 10.1016/j.vetpar.2011.11.006. Epub 2011 Nov 7.
A species of Hepatozoon closely related to Hepatozoon felis found in the skeletal and cardiac muscle of a wild Pampas gray fox (Lycalopex gymnocercus) is described. The fox was euthanized after showing severe incoordination. On necropsy and histopathology there was bilateral, diffuse, severe, sub-acute, necrotizing bronchointerstitial pneumonia, with intracytoplasmic and intranuclear eosinophilic inclusion bodies. Canine distemper virus was detected by immunohistochemistry in the bronchiolar epithelium, syncytial cells, alveolar macrophages and pneumocytes. The skeletal muscle and myocardium contained multiple round to oval protozoan cysts ranging from 64 μm × 75 μm to 98 μm × 122 μm, with a central eosinophilic meront-like core surrounded by concentric rings of mucinous material resembling Hepatozoon americanum cysts but smaller in size. Macrophages within rare pyogranulomas and monocytes/macrophages in adjacent sinusoidal blood vessels in the skeletal muscle contained intracytoplasmic round protozoa consistent with merozoites or developing gamonts of Hepatozoon. Hepatozoon sp. infection was confirmed by PCR of skeletal muscle and the sequenced 18S rRNA PCR product was found to be 99% identical to H. felis by BLAST analysis and deposited in GenBank as accession number HQ020489. It clustered together in the phylogenetic analysis with published H. felis sequences and separately from H. canis, H. americanum and other Hepatozoon species. However, the close relatedness of the fox Hepatozoon to H. felis does not rule out infection with a different and possibly unknown Hepatozoon species.
描述了一种与猫肝孢子虫密切相关的肝孢子虫，该虫存在于一只野生潘帕斯草原灰狐（Lycalopex gymnocercus）的骨骼肌和心肌中。这只狐狸因严重的不协调而被安乐死。剖检和组织病理学检查显示，双侧弥漫性、严重、亚急性、坏死性支气管间质性肺炎，细胞质和核内有嗜酸性包涵体。犬瘟热病毒通过免疫组织化学在细支气管上皮、合胞体细胞、肺泡巨噬细胞和肺细胞中被检测到。骨骼肌和心肌中含有多个圆形至椭圆形的原生动物囊肿，大小从 64μm×75μm 到 98μm×122μm，中央有嗜酸性的梅氏原虫样核心，周围有黏液物质的同心环，类似于肝孢子虫的囊肿，但体积较小。罕见的化脓性肉芽肿内的巨噬细胞和骨骼肌中相邻窦状血管内的单核细胞/巨噬细胞内含有胞质内圆形原生动物，与裂殖体或发育中的肝孢子虫配子体一致。通过肌肉组织 PCR 确认了肝孢子虫感染，并且通过 BLAST 分析发现测序的 18S rRNA PCR 产物与猫肝孢子虫高度同源，相似度为 99%，并在 GenBank 中作为 HQ020489 号注册。它在系统发育分析中与已发表的猫肝孢子虫序列聚类在一起，与犬肝孢子虫、肝孢子虫和其他肝孢子虫物种分开。然而，狐属肝孢子虫与猫肝孢子虫的密切关系并不能排除感染不同的、可能未知的肝孢子虫物种的可能性。
