A historical review of the techniques of recovery of parasites for their detection in human stools

Abstract Since the early 20th century, the detection of intestinal parasites has improved with the development of several techniques for parasitic structures recovery and identification, which differ in sensitivity, specificity, practicality, cost, and infrastructure demand. This study aims to review, in chronological order, the stool examination techniques and discuss their advantages, limitations, and perspectives, and to provide professionals and specialists in this field with data that lays a foundation for critical analysis on the use of such procedures. The concentration procedures that constitute the main techniques applied in routine research and in parasitological kits are a) spontaneous sedimentation; b) centrifugation-sedimentation with formalin-ethyl acetate; and c) flotation with zinc sulfate solution. While selecting a technique, one should consider the purpose of its application and the technical-operational, biological, and physicochemical factors inherent in the procedures used in stool processing, which may restrict its use. These intrinsic limitations may have undergone procedural changes driven by scientific and technological development and by development of alternative methods, which now contribute to the improvement of diagnostic accuracy.

摘要 自20世纪初以来，随着多种用于寄生虫体结构提取与鉴定的技术相继问世，肠道寄生虫检测水平得以提升；此类技术在灵敏度、特异性、实用性、成本及基础设施需求方面各有差异。本研究旨在按时间脉络系统梳理粪便检查技术，探讨其优势、局限性与发展前景，并为该领域专业人员与专家提供相关数据，为此类检测手段的应用开展批判性分析奠定基础。作为常规临床检验与寄生虫检测试剂盒中主流应用技术的粪便浓集法包括：a) 自然沉淀法；b) 福尔马林-乙酸乙酯离心沉淀法；c) 硫酸锌溶液漂浮法。在选用检测技术时，需综合考量其应用目的，以及粪便处理流程中固有的技术操作、生物学与物理化学因素，此类因素可能会限制该技术的实际应用。这些固有局限性可能会随着科技进步与替代检测方法的研发而得到流程优化，而此类优化目前正有效提升寄生虫检测的诊断准确率。