Answer to the Parasite Case of the Week 655: Microsporidia spores. Nucleic acid amplification/sequencing and/or electron microscopy is required for genus and species level identification.
Microsporidia that are commonly implicated in corneal infection include Vittaforma corneae and Encephalitozoon hellem.
As noted by Dr. Harsha Sheorey, the Ryan’s modified Trichrome stain was created by his friend and colleague, Dr Norbert Ryan. This stain has now become a standard staining technique for these organisms, and what was used in this case. The microsporidia spores stain bright red against a blue background.