Ocular phenotype in a patient with PAX2 gene mutation-associated papillorenal syndrome

Abstract

ABSTRACT Background Papillorenal syndrome is an autosomal dominant disorder associated with mutations in the gene PAX2 and often presents with characteristic and specific optic disc findings, frequently with renal dysplasia. In at least half of cases, an identifiable mutation in the PAX2 gene can be detected. We report the ocular findings in a second case of papillorenal syndrome with the c.350 G > C (p.Arg117Pro) mutation detected within the PAX2 gene. Methods A case report of papillorenal syndrome due to PAX2 mutation. Complete ophthalmologic examination was performed as well as color fundus photography, fundus autofluorescence, and optical coherence tomography (OCT). Genetic testing was performed using a next-generation sequencing with CNV calling (NGS-CNV) panel test containing 55 genes associated with nephrotic syndrome or focal segmental glomerulosclerosis. Results An 11-year-old boy who presented with hypertension and proteinuria was found to have stage IV chronic kidney disease. Presenting visual acuity was 20/25 in the right eye and 20/20 in the left eye. The fundus exam showed bilateral centrally excavated optic discs with absent central retinal vessels and a compensatory multiplicity of cilioretinal vessels, characteristic and specific for papillorenal syndrome. OCT showed outer retinal atrophy and macular schisis. Genetic testing identified the likely pathogenic c.350 G > C (p.Arg117Pro) mutation in PAX2. Conclusions We report the first description, to our knowledge, of the clinical presentation, ocular and systemic findings, and ophthalmic imaging in an individual with papillorenal syndrome associated with the PAX2 c.350 G > C (p.Arg117Pro) mutation. Our case adds to the current understanding of papillorenal syndrome and demonstrates that this condition is associated with a pathognomonic optic disc appearance and significant renal disease.