Department of Parasitology and Mycology, School of Medicine, International Campus, Iran University of Medical Sciences, Tehran, Iran.
Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
PLoS One. 2019 Oct 29;14(10):e0224501. doi: 10.1371/journal.pone.0224501. eCollection 2019.
Cystic echinococcosis (CE) is a worldwide zoonotic disease caused by the larval stage of Echinococcus granulosus. We investigated the presence of E. granulosus-specific DNA in the serum of CE patients by detecting the cytochrome c oxidase I (cox1) and NADH dehydrogenase subunit I (nad1) mitochondrial genes. Serum and formalin-fixed paraffin embedded (FFPE) cyst tissue samples of 80 CE patients were analyzed. The extracted DNA of samples was submitted to PCR amplification of cox1 and nad1 genes, and products were sequenced and genotyped. Nineteen (23.8%; 95% CI 15.8-34.1) serum and 78 (97.5%; 95% CI 91.3-99.3) FFPE cyst tissue samples were successfully amplified with at least one gene. Echinococcus DNA was detected in the sera of 15.0% (95% CI: 8.8-24.4) and 10.0% (95% CI: 5.2-18.5) and in cyst tissue of 91.3% (95% CI: 83.0-95.7) and 83.8% (95% CI: 74.2-90.3) of 80 patients by cox1 and nad1 gene, respectively. Four genotypes of E. granulosus were distinguished in the CE patients, with predominance of genotype G1, followed by G3, G2, and G6. The finding of E. granulosus DNA in 23.8% of serum samples from CE patients confirmed that E. granulosus releases cell-free DNA into the circulatory system, but quantities may be inadequate for the diagnosis of CE. Genotype G1 predominance suggests the sheep-dog cycle as the primary route of human infection.
泡型包虫病（CE）是一种全球性的人畜共患疾病，由细粒棘球绦虫的幼虫阶段引起。我们通过检测细胞色素 c 氧化酶 I（cox1）和 NADH 脱氢酶亚单位 I（nad1）线粒体基因，来研究 CE 患者血清中是否存在细粒棘球绦虫特异性 DNA。分析了 80 例 CE 患者的血清和福尔马林固定石蜡包埋（FFPE）囊组织样本。提取样本的 DNA 进行 cox1 和 nad1 基因的 PCR 扩增，对产物进行测序和基因分型。19 份（23.8%；95%CI 15.8-34.1）血清和 78 份（97.5%；95%CI 91.3-99.3）FFPE 囊组织样本至少扩增出一个基因。在 80 例患者的血清中检测到细粒棘球绦虫 DNA，cox1 和 nad1 基因检测的阳性率分别为 15.0%（95%CI：8.8-24.4）和 10.0%（95%CI：5.2-18.5），在囊组织中的阳性率分别为 91.3%（95%CI：83.0-95.7）和 83.8%（95%CI：74.2-90.3）。在 CE 患者中区分出了 4 种细粒棘球绦虫基因型，以 G1 基因型为主，其次是 G3、G2 和 G6。在 23.8%的 CE 患者血清样本中发现了细粒棘球绦虫 DNA，证实细粒棘球绦虫会将无细胞游离 DNA 释放到循环系统中，但数量可能不足以诊断 CE。G1 基因型为主表明羊-犬循环是人类感染的主要途径。
