Sharifdini Meysam, Derakhshani Sedigheh, Alizadeh Safar Ali, Ghanbarzadeh Laleh, Mirjalali Hamed, Mobedi Iraj, Saraei Mehrzad
Department of Medical Parasitology and Mycology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
Department of Parasitology and Mycology, School of Medicine, Qazvin University of Medical Sciences, Qazvin, Iran; Cellular and Molecular Research Center, Qazvin University of Medical Sciences, Qazvin, Iran.
Acta Trop. 2017 Dec;176:293-299. doi: 10.1016/j.actatropica.2017.07.001. Epub 2017 Jul 29.
Human infections with Trichostrongylus species have been reported in most parts of Iran. The aim of this study was the identification, molecular characterization and phylogenetic analysis of human Trichostrongylus species based on ITS2 region of ribosomal DNA from Guilan Province, northern Iran. Stool samples were collected from rural inhabitants and examined by formalin-ether concentration and agar plate culture techniques. After anthelmintic treatment, male adult worms were collected from five infected cases. Genomic DNA was extracted from one male worm of each species in every treated individual and one filariform larva isolated from each case. PCR amplification of ITS2-rDNA region was performed and the products were sequenced. Among 1508 individuals, 46 (3.05%) were found infected with Trichostrongylus species using parasitological methods. Male worms of T. colubriformis, T. vitrinus and T. longispicularis were expelled from five patients after treatment. Out of 41 filariform larvae, 40 were T. colubriformis, and the other one was T. axei. Phylogenetic analysis showed that each species was placed together with reference sequences submitted to GenBank database. Intra-species similarity for all species obtained in the current study was 100%. T. colubriformis was found to be probably the most common species in this region of Iran. For the first time, the authors of the present study report the occurrence of natural human infection by T. longispicularis in the world. Therefore, the number of Trichostrongylus species infecting human in Iran now increased to ten.
伊朗大部分地区都有人类感染毛圆线虫属物种的报道。本研究的目的是基于伊朗北部吉兰省核糖体DNA的ITS2区域，对人类毛圆线虫属物种进行鉴定、分子特征分析和系统发育分析。从农村居民中采集粪便样本，采用福尔马林-乙醚浓缩法和琼脂平板培养技术进行检测。驱虫治疗后，从5例感染病例中收集雄性成虫。从每个接受治疗个体的每种物种的一条雄性蠕虫和从每个病例中分离出的一条丝状幼虫中提取基因组DNA。进行ITS2-rDNA区域的PCR扩增并对产物进行测序。在1508名个体中，采用寄生虫学方法发现46人（3.05%）感染了毛圆线虫属物种。治疗后，从5名患者体内排出了蛇形毛圆线虫、透明毛圆线虫和长刺毛圆线虫的雄性蠕虫。在41条丝状幼虫中，40条为蛇形毛圆线虫，另一条为艾氏毛圆线虫。系统发育分析表明，每个物种都与提交到GenBank数据库的参考序列归为一类。本研究中获得的所有物种的种内相似度均为100%。蛇形毛圆线虫可能是伊朗该地区最常见的物种。本研究的作者首次报道了世界上自然发生的人类感染长刺毛圆线虫的病例。因此，目前在伊朗感染人类的毛圆线虫属物种数量增加到了10种。
