Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil.
São Camilo University Center, São Paulo, Brazil.
J Equine Vet Sci. 2022 Mar;110:103835. doi: 10.1016/j.jevs.2021.103835. Epub 2021 Dec 15.
Nocardioform placentitis is a pathologically unique form of placental disease first diagnosed in central Kentucky in the mid-80s. Since then, the occurrence of nocardioform placentitis in the region has varied over the years, from sporadic cases to outbreaks. The disease has been sporadically detected in other countries and has not been confirmed in South America. A 13-year-old multiparous Mangalarga delivered a healthy filly at 340d gestation. The mare passed the fetal membranes 33 minute after foaling. Gross examination of the fetal membranes identified two focal lesions on the chorionic surface consistent with focal mucoid placentitis. Histopathologic evaluation revealed hyperplasia and degeneration of the allantoic mesoderm, intense mononuclear inflammatory infiltrates with marked lymphocytes and plasma, and occasional macrophages and neutrophils in the microvilli. Necrotic debris and exudate were identified in the chorionic epithelium, with macrophages, plasma cells, and neutrophils confirming the diagnosis of focal mucoid placentitis. The exudate culture revealed white, firm, punctiform colonies of ∼1 mm diameter. Gram staining revealed bacilli with rounded ends and branching aspect typical of actinomycetes. PCR using primers for the 16S rRNA identified the genera of bacteria as Amycolatopsis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis identified the isolate as Amycolatopsis lexingtonensis. In conclusion, we described the first confirmed case of nocardioform placentitis in South America. The present case was associated with the birth of a full-term healthy live foal; this result is consistent with Amycolatopsis spp and, in this case, was caused by A. lexingtonensis.
诺卡氏菌样胎盘炎是一种病理性独特的胎盘疾病，于 80 年代中期在肯塔基州中部首次诊断。此后，该地区诺卡氏菌样胎盘炎的发生多年来有所波动，从散发病例到暴发。该疾病在其他国家也有零星发现，但在南美洲尚未得到证实。一例 13 岁经产母马在妊娠 340 天后产下一匹健康的驹。母马在分娩后 33 分钟排出胎膜。对胎膜的大体检查发现，在绒毛膜表面有两个局灶性病变，符合局灶性黏液性胎盘炎。组织病理学评估显示，尿囊中胚层增生和变性，微绒毛中有强烈的单核炎性浸润，伴有明显的淋巴细胞和浆细胞，偶尔有巨噬细胞和中性粒细胞。在绒毛膜上皮中发现坏死碎片和渗出物，巨噬细胞、浆细胞和中性粒细胞证实了局灶性黏液性胎盘炎的诊断。渗出物培养显示出约 1 毫米直径的白色、坚硬、点状的菌落。革兰氏染色显示出具有圆形末端和分支外观的杆菌，这是放线菌的典型特征。使用 16S rRNA 引物的 PCR 鉴定出细菌的属为 Amycolatopsis。基质辅助激光解吸/电离飞行时间质谱分析鉴定出分离株为 Amycolatopsis lexingtonensis。总之，我们描述了南美洲首例确诊的诺卡氏菌样胎盘炎病例。本病例与足月健康活驹的出生有关；这一结果与 Amycolatopsis spp 一致，在本例中，是由 A. lexingtonensis 引起的。
