The use of ancillary investigations in cytopathology improves diagnostic accuracy, helps subtype microorganisms, and determines their antimicrobial sensitivity. Newer detection methods are being increasingly introduced into routine clinical practice such as in situ hybridization (ISH) and molecular tests. This chapter covers the gamut of ancillary tests available for use with cytology specimens applicable to infectious diseases. Various stains including routine, special, and fluorescent stains are discussed, as well as cell block technique, immunocytochemistry, and ISH. More advanced methods like flow cytometry, signal amplification assays, and PCR are explained, as well as the role of traditional microbiology studies like serology and culture.
KeywordsCell Block Special Stain Fluorescent Stain Ancillary Investigation Cresyl Violet Acetate
Thanks to Carina Aitken, Head of the Special Stains Section, Department of Anatomical Pathology, School of Pathology, University of Witwatersrand, Johannesburg, SA, for invaluable advice on special staining procedures and pitfalls.