Fitzgerald Scott D, Sledge Dodd G, Maes Roger, Wise Annabel, Kiupel Matti
Michigan State University, Diagnostic Center for Population and Animal Health, Lansing, MI 48910-8107, USA.
J Vet Diagn Invest. 2009 Nov;21(6):878-82. doi: 10.1177/104063870902100621.
Bovine leukosis associated with infection with the delta retrovirus Bovine leukemia virus (BLV) is endemic in many cattle herds in the United States. Infection has been associated with immunosuppression and decreased productivity. Cases of tuberculosis in cows due to infection with Mycobacterium bovis reemerged in Michigan in 1998, and despite intensive eradication attempts, new cases of bovine tuberculosis are sporadically identified. The present report details a coinfection with BLV and M. bovis in a Holstein cow from Michigan that presented as part of a bovine tuberculosis screening program. Peripheral and visceral lymph nodes of this animal were markedly enlarged, homogeneously pale white, and bulged on the cut surface. The submandibular, mesenteric, and caudal mediastinal lymph nodes contained multifocal to coalescing caseogranulomas that ranged from 1 to 5 cm in diameter. Histologically, dense sheets of monomorphic populations of neoplastic lymphocytes obliterated the normal architecture of all lymph nodes. Caseogranulomas were characterized by central pools of amorphous degenerate eosinophilic and occasionally mineralized granular debris surrounded by thick rims of epithelioid macrophages, occasional Langhan's type giant cells, and fibrosis. Polymerase chain reaction assay was positive for BLV. Cultures of affected lymph nodes yielded growth of M. bovis.
与δ逆转录病毒牛白血病病毒（BLV）感染相关的牛白血病在美国许多牛群中呈地方性流行。感染与免疫抑制和生产力下降有关。1998年，密歇根州出现了因感染牛分枝杆菌导致奶牛患结核病的病例，尽管进行了密集的根除尝试，但仍偶尔发现新的牛结核病例。本报告详细介绍了密歇根州一头荷斯坦奶牛同时感染BLV和牛分枝杆菌的情况，该奶牛是作为牛结核病筛查项目的一部分出现的。这头动物的外周和内脏淋巴结明显肿大，呈均匀的苍白色，切面凸起。下颌下、肠系膜和纵隔后淋巴结含有多灶性至融合性的干酪样肉芽肿，直径从1厘米到5厘米不等。组织学上，密集的单形性肿瘤淋巴细胞群破坏了所有淋巴结的正常结构。干酪样肉芽肿的特征是中央有非晶态变性嗜酸性粒细胞池，偶尔还有矿化的颗粒碎片，周围是上皮样巨噬细胞厚边缘、偶尔的朗汉斯型巨细胞和纤维化。聚合酶链反应检测BLV呈阳性。受影响淋巴结的培养物培养出牛分枝杆菌。
