Endothelial Plaques as Sign of Hyphae Infiltration of Descemet's Membrane in Fungal Keratitis.

Abstract

Background To evaluate the relationship between corneal endothelial plaques and fungal hyphae infiltration in fungal keratitis. Methods Retrospective cross-sectional study of 60 fungal keratitis patients who underwent keratoplasty between January 2013 and March 2017. The endothelial plaques were graded as follows: grade 1, 1–3 endothelial plaques; grade 2, 4–8 endothelial plaques; and grade 3, more than 8 endothelial plaques or dense, merging endothelial plaques. The fungal pathogen culture and histopathology of diseased Descemet's membrane were evaluated. Results According to endothelial plaque grading, 3 patients were grade 1, 29 patients were grade 2, and 28 patients were grade 3. The PK surgery was performed in 57 patients with endothelial plaques of grade 2 and grade 3 and DALK surgery in 3 patients of grade 1. The predominating fungal pathogens were Aspergillus species (63.2%). All 57 patients with grade 2 and grade 3 had fungal hyphae in Descemet's membrane based on calcofluor white staining or PAS staining. In patients with grade 3, more hyphae and inflammatory cells were found in Descemet's membrane. The immunohistochemical staining of endothelial plaques revealed that CD15 and CD68 were positive in most cells. During the follow-up, 2 out of 3 patients who underwent DALK had recurrent fungal keratitis. Conclusions Endothelial plaques are considered as a sign of hyphae infiltrating Descemet's membrane. PK should be performed once plaques are detected in endothelium during the surgery.