CDH3 Retinopathy: Long-Term Multimodal Follow-Up with Pediatric Multidisciplinary Insights

Purpose: To describe the long-term, multimodal follow-up and multidisciplinary evaluation of two pediatric patients with CDH3-related retinopathy, discussing the genotypic and phenotypic spectrum of this rare cadherinopathy. Design: Retrospective observational case series. Methods: Two unrelated children with early-onset macular dystrophy and congenital hypotrichosis underwent a comprehensive ophthalmic examination, including spectral-domain optical coherence tomography (SD-OCT), blue-light fundus autofluorescence (BAF), microperimetry, and full-field electroretinography (ffERG), combined with dermatologic assessment and exome sequencing. Follow-up extended over 4 years in Patient 1 and 15 years in Patient 2. Results: Both patients showed sharply demarcated posterior pole chorioretinal atrophy with preservation of the peripheral retina and stable best-corrected visual acuity throughout follow-up. Microperimetry documented localized sensitivity loss with limited progression. SD-OCT revealed persistent ellipsoid zone disruption, retinal pigment epithelium atrophy, and outer retinal tubulations. Dermatologic evaluation confirmed congenital hypotrichosis without nail abnormalities; one patient exhibited mild fifth finger clinodactyly. Genetic testing identified the following two distinct homozygous CDH3 variants: a splice-site mutation (c.160+1G>A) and a frameshift insertion (c.1837dup, p.(Asp613Glyfs*4)). Conclusions:CDH3 retinopathy presents with a characteristic multimodal imaging pattern of localized macular atrophy and slow functional decline associated with congenital hypotrichosis. A comprehensive multidisciplinary approach was essential for the correct diagnosis and a better and more thorough definition of the clinical presentation. Detailed long-term follow-up supports the hypothesis of retinal pigment epithelium dysfunction or maldevelopment rather than widespread retinal degeneration. Recognition of this phenotype is critical for accurate diagnosis, genetic counseling, and future gene-therapy strategies targeting the preserved peripheral retina.