Purpose: To report a case of subepithelial infiltrates (SEIs) comprising Langerhans cells, 25 months after deep anterior lamellar keratoplasty (DALK) for keratoconus.
Methods: A case report based on clinical and confocal microscopic examination.
Results: A 26-year-old man with progressive keratoconus underwent left DALK. Routine follow-up 25 months postoperatively revealed a rust ring in the graft, scattered SEIs in the edematous donor anterior corneal stroma, and keratic precipitates. The graft cleared after removal of the rust ring and treatment with guttae prednisolone 1%. In vivo confocal microscopy showed accumulation of hyperreflective dendritic structures typical of Langerhans cells at the level of the basal epithelium and the Bowman membrane.
Discussion: DALK is an alternative to penetrating keratoplasty in patients with a healthy endothelium. Stromal rejection has been reported up to 41 months postoperatively after DALK. The SEIs and the stromal edema in this case indicated stromal rejection. Increased concentration of antigen-presenting Langerhans cells found on confocal microscopy of the SEIs point to their involvement in the stromal rejection in DALK cases.