In-vivo confocal observation of giant dendritic cells in Thygeson's superficial punctate keratitis

Abstract

In-vivo confocal microscopy of the cornea was performed in a 44 year-old male with an 11-year history of recurrent Thygeson's superficial punctate keratitis as diagnosed by clinical biomicroscopy. On confocal examination, hyperreflective areas, microdots and keratocyte activation were the most pronounced findings in the anterior stroma. A high dendritic cell density was noted in deeper epithelial cell layers and Bowman's membrane. There were 10.3% large mature cells with a mean size of 42 µm, measuring up to 105 µm. After eight weeks of topical treatment with rimexolone 1%, dendritic cell density and the proportion and size of mature dendritic cells had decreased. There were 3.2% mature cells with a mean size of 28 µm. A less corpuscular appearance of mature dendritic cells was noted. The present case serves to describe the reversible presence of uniquely large mature dendritic cells in a patient with severe recurrent Thygeson's superficial punctate keratitis. We suggest such giant dentritic cells and a high proportion of mature forms as a possible indicator of disease severity. Further studies are warranted to test the significance of dendritic cell morphology rather than quantity in Thygeson's superficial punctate keratitis.