Taghipour N, Nazemalhosseini-Mojarad E, Haghighi A, Rostami-Nejad M, Romani S, Keshavarz A, Alebouyeh M, Zali Mr
Dept. of Parasitology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Iran J Parasitol. 2011 Dec;6(4):41-5.
Cryptosporidium is a worldwide protozoan parasite and one of the most common causes of infection and diarrhea in humans and cattle. The aim of the present study was determination of subtypes of Cryptosporidium among children with diarrhea in Tehran by sequence analysis of the highly polymorphic 60-kDa glycoprotein (GP60) gene.
Fecal samples were collected from 794 diarrheic children. Initial identification of Cryptosporidium was carried out on stool samples by Ziehl-Neelsen acid-fast staining method. DNA was extracted from positive microscopically samples and Cryptosporidium genotypes and subtypes were determined, accordingly.
Out of 794 collected samples, 19 (2.40%) were positive for Cryptosporidium oocysts. Sequences analysis of GP60 gene showed that 17 (89.47%) of the positive isolates were Cryptosporidium parvum and 2 (10.52%) were C. hominis. All subtypes of C. parvum isolates belonged to allele families IIa (6/17) and IId (11/17). The most common allele in all 17 isolates belonged to IId A20G1a (41.18%). A22G1 (IF) subtype was detected in two C. hominis isolates of the children.
The predominancy of C. parvum species (specially, IId A20G1a subtype) in current study underlines the importance of zoonotic Cryptosporidium transmission in Iran.
隐孢子虫是一种全球范围内的原生动物寄生虫，是人类和牛感染及腹泻的最常见病因之一。本研究的目的是通过对高度多态性的60 kDa糖蛋白（GP60）基因进行序列分析，确定德黑兰腹泻儿童中隐孢子虫的亚型。
从794名腹泻儿童中采集粪便样本。通过齐-尼抗酸染色法对粪便样本进行隐孢子虫的初步鉴定。从显微镜检查阳性的样本中提取DNA，并据此确定隐孢子虫的基因型和亚型。
在794份采集的样本中，19份（2.40%）隐孢子虫卵囊呈阳性。GP60基因序列分析表明，17份（89.47%）阳性分离株为微小隐孢子虫，2份（10.52%）为人体隐孢子虫。微小隐孢子虫分离株的所有亚型均属于等位基因家族IIa（6/17）和IId（11/17）。所有17份分离株中最常见的等位基因属于IId A20G1a（41.18%）。在两名儿童的人体隐孢子虫分离株中检测到A22G1（IF）亚型。
本研究中微小隐孢子虫物种（特别是IId A20G1a亚型）的优势突出了伊朗人畜共患隐孢子虫传播的重要性。
