Retinitis Pigmentosa Sine Pigmento in a Patient With a Heterozygous Mutation on the KIF7 Gene: A Case Report

Overview

Journal Cureus

Specialty Biomedical Engineering

Date 2024 Jul 22

PMID 39036105

Authors

Sebastian J Ruiz-Matos

Armando J Ruiz-Justiz

Natalio Izquierdo

Affiliations

Soon will be listed here.

Abstract

Mutations in the gene have been implicated in autosomal recessive conditions such as Joubert syndrome, acrocallosal syndrome, and fetal hydrolethalus, as well as in retinal degeneration and other ocular manifestations due to their effect on primary cilia. In this study, we report that the full-field electroretinogram (ERG) test showed non-recordable scotopic ERG responses, while photopic ERG responses were diminished bilaterally. This is a case report of a 62-year-old female patient with painless, progressive vision loss in both eyes. Fundus examination revealed a pale optic nerve head, vessel attenuation, and macular thinning without peripheral pigmentary changes. The full-field electroretinogram (ERG) test showed non-recordable scotopic ERG responses, while photopic ERG responses were diminished bilaterally. Based on these ocular findings, the patient was clinically diagnosed with retinitis pigmentosa (RP) sine pigmento. Genetic testing identified a pathogenic heterozygous mutation in the gene with the variant c.61C>T (p.Arg21*). Our case suggests that this pathologic variant may be associated with RP sine pigmento. Further studies are warranted to better understand the role of the gene in retinal dystrophies.

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