Clinical course of a patient with PRSS56-associated nanophthalmos (isolated microphthalmia) and uveal effusion syndrome.

Abstract

Purpose: To describe the detailed clinical course and genetic findings of a Japanese patient with nanophthalmos (isolated microphthalmia) who developed bilateral uveal effusion syndrome (UES).

Case report: A 50-year-old Japanese man presented with distorted and decreased vision in his right eye. Ophthalmoscopy revealed non-rhegmatogenous retinal detachment with shifting subretinal fluid. The horizontal corneal diameter was 11.5 mm in both eyes, while the axial lengths were 15.6 and 15.3 mm in the right and left eyes, respectively, confirming the diagnosis of nanophthalmos (microphthalmia)-associated UES. After steroid pulse therapy followed by sclerectomy with vortex vein decompression (S-VVD), the UES resolved 10 months postoperatively. The eyes remained stable for 15 years, after which the patient developed bilateral cataracts and elevated intraocular pressure. Cataract surgery was done uneventfully, but signs of UES appeared in the left eye five days postoperatively. This was controlled with multiple treatments, including steroid pulse therapy, intravitreal anti VEGF injection, and oral carbonic anhydrase inhibitor. However, UES recurred after five months. S-VVD and vitrectomy with silicone oil tamponade were performed, and the UES resolved after one year postoperatively. Ultimately, electroretinography (ERG) became non-recordable, and the visual fields were constricted in both eyes. Whole-exome sequencing identified a previously unreported homozygous nonsense variant in PRSS56 (c.202C>T, p.Arg68Ter), classified as pathogenic based on the ACMG criteria.

Conclusions: This report describes a patient with an unreported pathogenic PRSS56 variant who exhibited a typical and severe course of nanophthalmos (isolated microphthalmia) complicated by bilateral UES. Although the effusions eventually resolved after multiple interventions, the prolonged UES was challenging to manage and resulted in irreversible retinal dysfunction with a non-recordable ERG.