Department of Medical Parasitology, Faculty of Medicine, Al-Azhar University, Damietta, Egypt.
Department of Medical Parasitology, Faculty of Medicine, Al-Azhar University, Cairo, Egypt.
Egypt J Immunol. 2023 Apr;30(2):1-10.
Blastocystis is a polymorphic enteric parasite with a worldwide distribution. It is one of the most common human intestinal protozoans in developing countries. The primary objective of this study was to determine the diagnostic value of microscopy, stool culture, and a polymerase chain reaction (PCR) technique for assessment of Blastocystis prevalence and risk factors. Human stool samples were collected from 110 individuals from Dakahlia governorate, Egypt as a part of a routine check-up or having gastrointestinal tract (GIT) symptoms. These samples were subjected to direct fecal smear microscopy, culture, and PCR for the detection of Blastocystis sp. Positive results for Blastocystis screening among the study population were 36 (32.7%), 41 (37.3%), and 43 (39.1%) by microscopy, PCR, and culture, respectively. Statistical analyses demonstrated that the agreement between the culture and PCR was perfect (Κ=0.925). Compared to culture, the sensitivity of PCR was 95% and the specificity was 97% while the sensitivity of microscopy was 84% and the specificity was 90.5%. We concluded that the in vitro culture and molecular assay have significant diagnostic value for the accurate detection and identification of Blastocystis in stool samples. The pathogenic potential of Blastocystis cannot be ruled out because our results found a link between Blastocystis carriage and gastrointestinal symptoms.
芽囊原虫是一种具有世界性分布的多态性肠道寄生虫。它是发展中国家最常见的人类肠道原生动物之一。本研究的主要目的是确定显微镜检查、粪便培养和聚合酶链反应（PCR）技术在评估芽囊原虫流行率和危险因素方面的诊断价值。从埃及达卡利亚省的 110 个人中收集了人类粪便样本，作为常规检查或有胃肠道（GIT）症状的一部分。这些样本通过直接粪便涂片显微镜检查、培养和 PCR 来检测芽囊原虫 sp。研究人群中芽囊原虫筛查的阳性结果分别为显微镜检查 36（32.7%）、PCR 检测 41（37.3%）和培养检测 43（39.1%）。统计分析表明，培养与 PCR 之间的一致性为完美（Κ=0.925）。与培养相比，PCR 的敏感性为 95%，特异性为 97%，而显微镜检查的敏感性为 84%，特异性为 90.5%。我们得出结论，体外培养和分子检测对准确检测和鉴定粪便中的芽囊原虫具有重要的诊断价值。芽囊原虫的致病潜力不能排除，因为我们的结果发现芽囊原虫携带与胃肠道症状之间存在联系。
