Expanded Phenotype of PAX2 ‐Related Papillorenal Syndrome: A Case Featuring FSGS , Atypical Retinopathy, Cerebellar Hypoplasia, and ADHD

ABSTRACT Papillorenal syndrome (PAPRS), or renal coloboma syndrome, is a rare autosomal dominant disorder caused by PAX2 mutations. It classically manifests with renal hypodysplasia and optic nerve anomalies. However, recent literature suggests an expanding phenotypic spectrum. We report a 7‐year‐8‐month‐old boy born to consanguineous parents, presenting with stage 4 chronic kidney disease (CKD), nephrotic‐range proteinuria, visual impairment, and ADHD. Renal biopsy revealed focal segmental glomerulosclerosis (FSGS), and ocular examination showed bilateral peripheral scalloped chorioretinal atrophy without optic nerve colobomas. Genetic testing confirmed a pathogenic heterozygous PAX2 frameshift mutation (c.69_70insG; p.Val26fs28*), establishing the diagnosis of PAPRS. This case illustrates an expanded phenotype of PAX2 ‐related PAPRS, including FSGS, atypical retinal degeneration, cerebellar hypoplasia, and ADHD. Recognition of such atypical presentations is vital for early diagnosis and multidisciplinary management, especially in resource‐limited settings where classic features may be absent.