%0 Case Reports %T An incipient late-onset retinal degeneration with a C1QTNF5 mutation: a case report with an 11-year follow-up. %A Torrell-Belzach N %A Miere A %A Bhouri R %A Srour M %A Souied EH %A Zambrowski O %J Doc Ophthalmol %V 148 %N 1 %D 2024 Feb 21 %M 38129706 %F 1.854 %R 10.1007/s10633-023-09958-3 %X OBJECTIVE: The purpose of this study was to describe and diagnose the difficulty in a long-term follow-up (eleven years) patient with a very early presentation of late-onset retinal degeneration (L-ORD) and the significance of electrophysiological examinations and follow-up in assessing undiagnosed inherited retinal diseases.
METHODS: This is an observational case report of a 56-year-old woman, with scattered multiple yellow-white retinal dots firstly diagnosed as fundus albipunctatus. Ten years after presentation, a deterioration in rod and cone responses in ff-ERG was detected, which allowed us to discard the first diagnostic hypothesis and proceed with a genetic testing.
RESULTS: Ten years after presentation, she presented a clear progression of the abnormal photoreceptor response with a cone and rod involvement in ff-ERG, which was not compatible with the previous suspicion of fundus albipunctatus. Six months later, genetic testing results together with the typical progression of atrophic patchy lesions in multimodal imaging allowed a certain diagnosis of L-ORD, caused by an already reported pathogenic variant in the C1QTNF5 gene (c.563C > T; p. Pro188 Leu).
CONCLUSIONS: We demonstrate the importance of the ff-ERG examination and the follow-up (or ERG and imaging repetition) in the differential diagnosis of an incipient L-ORD, which can be easily misdiagnosed in the early stages, before the appearance of the characteristic chorioretinal atrophy seen with the progression of this rare disease.