Corneal endothelial neovascularization and glaucoma in X-linked Alport syndrome

Introduction: Variants in COL4A5 are responsible for X-linked Alport syndrome. It is characterized by kidney disease, sensorineural hearing loss and variable ocular abnormalities. In this case, a woman with corneal endothelial neovascularization, glaucoma, nuclear cataract, temporal retinal thinning, and renal defects was identified with a variant in COL4A5. Case presentation: We described a 64-year-old woman who was referred to our Eye Clinic due to a progressive decline in vision in both eyes over the course of two years. Corneal endothelial neovascularization, elevated intraocular pressure (31.2 mmHg and 27.8 mmHg in the right and left eyes, respectively), lens opacity, an increased cup-to-disc (C/D) ratio (0.8 in both eyes), and thinner retinal nerve fiber layer were detected upon examination. Concurrently, microscopic hematuria and proteinuria were observed. Following phacoemulsification and the administration of Latanoprost, intraocular pressure returned to within the normal range. Whole exome sequencing revealed a novel hemizygous missense pathogenic variant in COL4A5 (c.3980G > T (p.G1327V)). Importantly, this particular variant was not identified in the healthy daughter of the proband, underscoring its potential relevance to the observed clinical manifestations. Conclusions: Our study reports a novel phenotype observed in a 64-year-old woman, featuring corneal endothelial neovascularization and glaucoma, which has been linked to X-linked Alport syndrome caused by variants in COL4A5. This discovery contributes to the broadening of our understanding of the clinical heterogeneity associated with COL4A5 variants.