[Enhanced microscopic diagnosis of oesophageal candidiasis through additional cytospin analysis of the fixative of oesophageal biopsies].

To confirm or to refute the diagnosis of candida oesophagitis as the most common infectious disease of the oesophagus is a standard diagnostic procedure in histopathology. The fungal hyphae colonise mainly the superficial layers of the oesophageal squamous mucosa. Tangentially cut sections of oesophageal biopsies in the paraffin block might lead to a false negative result concerning mycotic infection. The aim of this study was to investigate whether cytospin analysis of the formalin fixative in which the biopsies were stored and transported would be a tool to close the diagnostic gap.Oesophageal biopsies from 150 consecutive patients with the clinical diagnosis or question "candida" or "candida oesophagitis" have been investigated. The biopsies were routinely processed and stained with haematoxylin and eosin and periodic acid-Schiff reaction. In parallel, the fixative fluid, usually disposed of after use, was processed by using a cytospin centrifuge and prepared for cytological proof of fungal hyphae. The cytology slides were also stained with periodic acid-Schiff reaction. In this blind study, the pathologist investigating the results of one procedure was unaware of the results of the second procedure.Out of 89 positive cytology cases, 64 cases (71,9 %) also showed a positive histology result. In the remaining 25 cases (28,1 %), fungal hyphae were seen only after re-evaluation of the original histology slides (n = 6) or in further serial sections using the complete tissue in the block (n = 5). In 14 cases, no hyphae could be detected histologically. Only in one of the 61 cytospin-negative cases was candida seen in histology.Our results show that diagnosing oesophageal candidiasis can be improved by more than one quarter using the formalin fixative for cytospin cytology.