An unusual segmental retinal venous abnormality detected during retinopathy of prematurity screening in an infant with a PAX2 variant.

PURPOSE: Congenital abnormalities of retinal venous development are rare and may be difficult to distinguish from prematurity-related vascular changes when detected during retinopathy of prematurity screening. In premature infants, atypical posterior pole vascular findings should not be automatically attributed to retinopathy of prematurity alone. The purpose of this report is to describe an unusual segmental retinal venous abnormality detected during retinopathy of prematurity screening in a premature infant with a PAX2 variant and renal dysplasia. METHODS: We report a premature male infant born at 30 + 1 weeks of gestation with a birth weight of 1350 g who underwent screening for retinopathy of prematurity. Ophthalmic evaluation included fundus examination and wide-field fluorescein angiography, together with genetic testing and systemic evaluation. RESULTS: Fundus examination revealed mild bilateral stage 1-2 retinopathy of prematurity without plus disease. In the right eye, the inferotemporal retinal venous pattern was anomalous, with attenuated vessels and an altered course compared with the fellow eye. Wide-field fluorescein angiography demonstrated preserved arterial filling and markedly reduced or delayed venous opacification in the inferotemporal quadrant, associated with sectoral peripheral capillary nonperfusion and collateral-like vessels. No retinal hemorrhage, venous engorgement, abrupt vascular cutoff, leakage, neovascularization, or arteriovenous shunting was observed. Genetic testing identified a heterozygous missense variant in PAX2, NM_000278.5:c.98T>C, p.(Leu33Pro); the ACMG/AMP criteria specified in the laboratory report supported a likely pathogenic classification. Systemic evaluation revealed mild bilateral renal dysplasia; other systems were unremarkable. Retinal findings remained stable during follow-up, without progression of retinopathy of prematurity or development of neovascular complications. CONCLUSIONS: This case highlights an unusual segmental retinal venous abnormality detected during retinopathy of prematurity screening in an infant with a PAX2 variant and renal dysplasia. Although a causal relationship cannot be established from a single observational case, careful recognition of atypical posterior pole vascular findings may prompt genetic and systemic evaluation.