Avicenna Veterinary Research

Avicenna Veterinary Research

A Comprehensive Review of Fixatives Used in Diagnostic Parasitology: Morphological Preservation, Technical Performance, and Modern Applications

Document Type : Review Articles

Authors
1 Department of Parasitology and Mycology, School of Medicine, Arak University of Medical Sciences, Arak, Iran
2 Student Research Committee, Arak University of Medical Sciences, Arak, Iran
10.22084/avr.2026.32296.1031
Abstract
Background: The selection of an appropriate stool xative is pivotal for preserving parasite morphology and ensuring diagnostic accuracy in intestinal parasitology. Each xative exhibits distinct advantages and limitations with respect to biosafety, compatibility with staining techniques, and applicability to molecular diagnostics. This review provides a systematic comparative evaluation of commonly used xatives and offers evidence-based guidance to support their optimal selection in contemporary diagnostic laboratories.
Methods: A comprehensive literature search was performed across PubMed, Scopus, Web of Science, and Google Scholar to identify studies investigating fecal xatives used in the diagnosis of intestinal parasites.
Results: 10% formalin remains the gold standard for helminth preservation but is unsuitable for delicate trophozoites and molecular assays. PVA and Schaudinn's xatives provide excellent protozoan morphology yet are limited by mercury related safety concerns. Mercury-free alternatives such as SAF, modi ed PVA, and single-vial systems offer safer and more versatile options, although with certain trade-offs in staining quality and consistency. Conclusion: No single xative meets all diagnostic needs. Choice should consider parasite type, laboratory setting, downstream applications, and safety regulations.
Keywords

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