Potocki–Shaffer syndrome associated with Brown syndrome: expansion of the ocular phenotype in a child with an 11p11.2–p11.12 deletion

PURPOSE: To describe the first reported case of Potocki-Shaffer syndrome (PSS) associated with Brown syndrome and to expand the ocular phenotype of this rare contiguous gene deletion syndrome. METHODS: Retrospective case report with multidisciplinary ophthalmologic, neurologic, radiologic, and genetic evaluation over a 5-year follow-up period. RESULTS: A 9-month-old girl presented with congenital esotropia, nystagmus, and facial dysmorphism. Ocular motility examination demonstrated bilateral limitation of elevation in adduction, consistent with Brown syndrome, together with right esotropia. During multidisciplinary follow-up, she was diagnosed with Potocki-Shaffer syndrome based on characteristic clinical features, including biparietal foramina, developmental delay, obesity and epilepsy. Chromosomal microarray analysis identified a heterozygous 6.903-Mb deletion at 11p11.2-p11.12 [arr[hg19] 11p11.2p11.12(43,686,617- 50,589,224)×1], encompassing the principal Potocki-Shaffer syndrome genes EXT2, ALX4, and PHF21A. CONCLUSION: This report documents the first known association between Potocki-Shaffer syndrome and Brown syndrome, thereby expanding the ocular phenotype of this rare genetic disorder. Recognition of this association may facilitate earlier diagnosis and prompt comprehensive multidisciplinary evaluation in children presenting with strabismus accompanied by developmental delay, craniofacial abnormalities, neurological manifestations, and skeletal anomalies.