[Polymorphism and modern diagnostic approaches for Leber congenital amaurosis].

Abstract

Purpose: This study investigated the prevalence and morphofunctional characteristics of the retina in the diagnosis of various types of Leber congenital amaurosis (LCA) among patients from Moscow and the Moscow region, based on the data from the Consultative and Diagnostic Center of the Morozov Children's City Clinical Hospital.

Material and methods: In order to analyze the polymorphism and prevalence of LCA, the study examined a total of 226 patients suspected of having hereditary retinal dystrophies, genetic diagnosis of Leber amaurosis was confirmed in 24 patients. All 24 patients underwent electrophysiological tests, including visual evoked potentials (VEP) from the sensory retina to the visual centers, and electroretinography (ERG) of the posterior pole of the retina. In children over 5 years old, additional methods were used: optical coherence tomography (OCT), fundus photography, and fundus autofluorescence (FAF) using a fundus camera.

Results: According to the molecular genetic analysis, the most frequent type was LCA type 10 (37%), followed by LCA type 2 (16%). The most common clinical manifestations among patients were nystagmus, impaired night vision, waxy optic disc pallor, narrowed arteries, and changes on the ERG. OCT revealed changes in the outer retinal layers in all patients. ERG showed abnormalities in 100% of the patients, with the maximal ERG either not being recorded or significantly reduced. During VEP, most patients exhibited configuration disturbances, increased latency, and a sharp decrease in the amplitude of the P100 component.

Conclusion: The analysis of patients with genetically confirmed Leber amaurosis revealed that LCA type 10 caused by mutations in the CEP290 gene was the most common (37%), followed by LCA type 2 (16%) caused by mutations in the RPE65 gene.