A Case of Irreversible Corneal Edema Associated with Dentatorubropallidoluysian Atrophy Following Corneal Endothelial Transplantation

Dentatorubropallidoluysian atrophy (DRPLA) is an autosomal dominant cerebellar ataxia with various signs and symptoms, including progressive ataxia, choreoathetosis, dementia, myoclonus, psychiatric problems, and seizures. Corneal endothelial degeneration and a remarkable reduction in endothelial cell density have been reported in cases of DRPLA; however, the severity of this disease usually does not reach a level that requires corneal transplantation. We report the first case of irreversible corneal edema associated with DRPLA that required corneal endothelial transplantation. A 52-year-old man noticed gait disturbance and was referred and diagnosed with DRPLA through an MRI scan; atrophy of the cerebellum, brain stem, and parietal lobe were documented. A DNA fragment analysis indicated an expanded allele and a normal allele of the ATN1 gene (56/19 repeats). He had corneal edema and cataract in his left eye, and specular microscopy revealed an uncountable corneal endothelial density. After cataract surgery, he underwent corneal endothelial transplantation by Descemet stripping automated endothelial keratoplasty. Two years after the surgery, the best-corrected visual acuity in his left eye improved from 20/250 to 20/50 with 2053 cells/mm2. This case indicates that DRPLA is associated with subclinical corneal endothelial cell degeneration and may lead to visual disturbances due to irreversible corneal edema, requiring corneal transplantation.