Supplementary Material for: Tractional retinoschisis: a subtle and rare manifestation of X-linked Alport Syndrome - case report

Introduction: Alport syndrome is a genetic condition characterized by chronic kidney disease, hearing loss and a wide range of ophthalmological alterations. We describe the case of a patient with X-linked Alport syndrome whose main ocular manifestation was peripapillary retinoschisis.Case presentation: A 60-years-old woman was observed in our department after suspicion for Alport syndrome was raised in her son. She had no visual complaints. On observation the patient had 20/25 Snellen best corrected visual acuity on both eyes and mild peripheral fleck retinopathy. Optical Coherence Tomography revealed the presence of bilateral peripapillary retinoschisis, multiple cysts within the retinal nerve fiber layer on both eyes and vitreomacular adhesion on the left eye. Full field electroretinogram was considered normal and autofluorescence retinography depicted mottled hyper and hypo autofluorescent areas in the peripheral retina bilaterally. Genetic study identified a specific undescribed COL4A5 mutation in heterozygosity in the patient and in hemizygosity in her son.Conclusion: Alport syndrome is frequently associated with fleck retinopathy and lenticonus, but a wide range of ocular manifestations may be present. It is important to identify rarer and more subtle ocular phenotypes, especially among women with X-linked Alport syndrome, who tend to be underdiagnosed.