A ROD–CONE DYSTROPHY IS SYSTEMATICALLY ASSOCIATED TO THE RTN4IP1 RECESSIVE OPTIC ATROPHY. Issue 8 (August 2021)

• Record Type: Journal Article
• Authors: Meunier, Isabelle; Bocquet, Béatrice; Charif, Majida; Dhaenens, Claire-Marie; Manes, Gael; Amati-Bonneau, Patrizia; Roubertie, Agathe; Zanlonghi, Xavier; Lenaers, Guy
• Is Part Of: Retina. Volume 41:Issue 8(2021)
• Publication Date: 2021-08
• Subjects: inherited optic neuropathy -- recessive disease -- rod–cone dystrophy -- RTN4IP1; Retina -- Diseases -- Periodicals; Retinal Diseases; Vitreous Body; 617.735
• DOI: 10.1097/IAE.0000000000003054
• Languages: English
• ISSNs: 0275-004X

Abstract

Abstract : Purpose: RTN4IP1 biallelic mutations cause a recessive optic atrophy, sometimes associated to more severe neurological syndromes, but so far, no retinal phenotype has been reported in RTN4IP1 patients, justifying their reappraisal. Methods: Seven patients from four families carrying biallelic RTN4IP1 variants were retrospectively reviewed, with emphasis on their age of onset, visual acuity, multimodal imaging including color and autofluorescence frames, spectral-domain optical coherence tomography with RNFL and macular analyses. Results: Seven patients from four RTN4IP1 families developed in their first decade of life a bilateral recessive optic atrophy with severe central visual loss, and primary nystagmus developed in 5 of 7 patients. Six patients were legally blind. In a second stage, the seven individuals developed a rod–cone dystrophy, sparing the macular zone and the far periphery. This retinal damage was identified by 55° field fundus autofluorescence frames and also by spectral-domain optical coherence tomography scans of the temporal part of the macular zone in five of the seven patients. Full-field electroretinography measurements disclosed reduced b-wave amplitude of the rod responses in all patients but two. Family 4 with the p.R103H and c.601A > T (p.K201*) truncating mutation had further combined neurological signs with cerebellar ataxia, seizures, and intellectual disability. Conclusion: RTN4IP1 recessive optic atrophy is systematically associated to a rod–cone dystrophy, which suggests that both the retinal ganglion cells and the rods are affected as a result of a deficit in the mitochondrial respiratory chain. Thus, systematic widefield autofluorescence frames and temporal macular scans are recommended for the evaluation of patients with optic neuropathies. Abstract : Although RTN4IP1 has been firmly associated to recessive optic atrophies, we identified by systematic examination of the 55° fundus autofluorescence frames and the peripheral spectral-domain optical coherence tomographic images, a progressive rod–cone dystrophy in all individuals with biallelic RTN4IP1 mutations.