绵羊棘球蚴病的病原学鉴定及组织病理学观察

从疑似棘球蚴病病羊的肝以及肺分离包囊,抽取囊液,离心取沉淀,分离基因组DNA,用PCR方法扩增NADH脱氢酶亚基1(ND1)基因并测序,对棘球蚴感染羊进行了病原学鉴定,并对患病羊的肝和肺病灶进行了病理学分析,以确定病原体的性质及所致的组织病理学变化。BLAST分析结果显示,所获ND1序列与细粒棘球绦虫(G1基因型)ND1序列的相似性达99.9%,判定该病例由G1型细粒棘球蚴引起。取包囊及其周围肝、肺组织进行石蜡切片、HE染色,观察结果显示,细粒棘球蚴包囊的形成对肝和肺造成的损伤是多方面的,除有压迫性组织萎缩,结缔组织及胆管大量增生造成的肝硬变外,尚见肝急性变性、过敏性炎症反应等。肺除压迫性萎陷外,还有间质增生炎症、囊液外渗引起的过敏反应等。本研究表明,采用PCR方法可以准确确定该病的病原性质,结合病理学观察分析,可揭示羊细粒棘球蚴病引起的组织病理学变化及器官损伤的机制。

Pathological identification and histopathological observation of ovine echinococcosis

The aim of the present study was to pathological identification and pathological diagnosis of a suspected case of hydatid disease in sheep,which identifies the pathogen and histopathological changes in hepatic and lung tissues.Cysts were respectively collected from the liver and lung of a sheep with suspected echinococcosis,and used for extraction of genomic DNA.Mitochondrial ND1 gene of Echinococcus was amplified by PCR and sequenced.BLAST analysis revealed 99.9% identity to the ND1 of sheep strain of E.granulosus(G1),which meant that this case belonged to E.granulosus infection.Liver and lung tissues with cysts were fixed in 100 mL/L buffered formalin,embedded in paraffin,sectioned,and stained with hematoxylin and eosin for routine examination under microscope.The pathological observation indicated that hydatid cysts were harmful to host liver and lung.The damages included pressure atrophy caused by increased size of the cyst itself,and cirrhosis caused by proliferation of liver connective tissue and bile ducts,respectively.Additionally,the formation of the cyst was also able to lead to acute liver degeneration and allergic inflammation.The harm to lung caused by hydatid disease included atelectasis,interstitial hyperplasia inflammation and allergic inflammation.The present study identified the pathogen of the ovine echinococcosis with PCR method,and incorporating with pathological analysed a much better understanding of histopathological lesion and pathogenesis of ovine echinococcosis was revealed.