Epidemiology of Retinal Dystrophies in a French Cohort of Patients

Abstract

Purpose: : Review phenotypes of patients attending our retinal dystrophy clinics over a 6-month period.

Methods: : 308 patients with a diagnosis of inherited retinal disease were included in the study. Detailed phenotypic characterization included family history, visual acuity, fundus examination, color vision, visual field, full-field electroretinogram, multifocal ERG, fundus autofluorescence and OCT. Patients were asked to donate a blood sample for future genotyping analysis.

Results: : Patients ages range from 11 to 82 (average 50.6; median 44 years) with 44.3% males, 55.7% females. For 29 patients, the diagnosis of inherited retinal disease was not confirmed after examination (7 normal clinical examination, 11 inflammatory disorders, and 1 Leber Hereditary Optic Neuropathy). Patients with inherited retinal disease (279), after phenotypic characterization, were classified in 3 groups: generalized progressive retinal dystrophy (79.9%), stationary retinal disorders (2.5%) and macular dystrophies (17.6%). Among patients with generalized retinal disease: 68.2% had rod-cone dystrophies with 67.1% autosomal recessive, 25.7% autosomal dominant and 7.2% X-linked recessive inheritance. Patients with cone-rod dystrophies represent 15.7% with 2.9% autosomal recessive; 4.3% autosomal dominant and 82.8% X-linked recessive inheritance; 9 (4%) suffered from Leber Congenital Amorosis or early-onset retinal dystrophies; 18 (8.1%) had Usher type (8 type I and 10 type II), 4 (1.8%) Bardet Biedl Syndrome, 6 (2.7%) choroideremia, 5 X-Linked retinoschisis, 1 gyrate atrophy, 1 Familial Exudative Vitreoretinopathy, 1 LORD, Among stationary disorders, 5 showed congenital stationary night blindness, 1 deuteranopia and 1 achromatopsia. Among the 49 patients with macular dystrophies, 26 (53.1%) had Stargardt disease, 5 Best disease, 2 pseudo-vitelliform macular dystrophy, 5 pattern dystrophies; 2 central areolar atrophy, 1 Doyne Honey-comb dystrophy and, 8 unlabelled maculopathy;

Conclusions: : In this large French cohort, the main group is represented by generalized progressive retinal dystrophy. It also delivers novel epidemiologic data concerning other types of inherited retinal diseases, less reported in the literature. These findings are a prerequisite for future genotyping analysis.

Keywords: retinal degenerations: hereditary • genetics • clinical (human) or epidemiologic studies: prevalence/incidence