An uncommon case of retinitis pigmentosa patients based on clinical and genetic study.

Abstract

Inherited retinal dystrophy (IRD) is a group of phenotypes caused by mutations in visual pathways-related genes, mostly occurring at photoreceptors. This heterogeneous group includes retinitis pigmentosa (RP) recognised by bone spicule at the peripheral retina and the other is Stargardt with macular pisiform flecks. In this study, a 20- year-old male patient with RP symptoms was accompanied by a yellowish pisiform flex in the macula. However, his brother, mother and aunty have typical Stargardt disease. This study involved four persons, two males (cases 1 and 2), their mother (case 3) and aunt (case 4). Initially, cases 1 and 2 came to the clinic, case 1 was diagnosed as RP and macular dystrophy, and case 2 was diagnosed as Stargardt disease. On the follow-up, cases 1 and 2 as well as their father, mother and other family members underwent comprehensive eye examination, including fundus, Snellen, OCT, OCT-A and HFA, and found an uncommon macular abnormality besides typical RP appearance in case 1. The father is healthy while the mother and one of his aunties were diagnosed as Stargardt. A genetics analysis was conducted in case 1, finding various mutations associated with IRD mutation at the cone protein-encoded gene that concentrated at the central and rod protein-encoded gene concentrated at the peripheral retina. Whether the combination of multiple or the same mutations is responsible for this RP phenotype needs further analysis and validation. Cases 2 and 3 genetic analysis showed similar mutation results but with a healthy peripheral retina and only represented Stargardt. Case 1 is considered as RP with macular dystrophy, while cases 2, 3 and 4 are confirmed as Stargardt.