Eight years follow‐up of two choroideremia patients with a new mutation of the choroideremia gene

• Published in: Acta ophthalmologica (Oxford, England) England), 2022-12, Vol.100 (S275), p.n/a
• Main Authors: Díaz‐Barreda, Mª. Dolores, Boned‐Murillo, Ana, Bartolome, Isabel, Hospital, Elvira Orduna, Fernández‐Espinosa, Guisela, Sopeña, María, Pinilla, Isabel
• Format: Article
• Language: English
• Subjects: Acuity; Electroretinograms; Mutation; Nyctalopia; Retina; Retinal degeneration; Retinitis; Retinitis pigmentosa; Sensitivity analysis; Visual field
• ISSN: 1755-375X; 1755-3768
• DOI: 10.1111/j.1755-3768.2022.0719

Purpose: Choroideremia (CHM) is an inherited retinal dystrophy with an X‐linked inherited patron. It presents changes in the outer retina and choroid. CHM has a typical fundus appearance with preservation of the central retina, that progresses over the years. Fundus autofluorescence (FAF) shows the changes in the pigment distribution not only in patients but also in carriers. We present an 8‐year follow‐up of two boys affected by the disease. Methods: We studied a family with two cousins referring visual loss and nyctalopia and presented clinical findings of CHM at 11 and 10 years old. Their mothers referred that their deceased father had an important loss of visual acuity (VA) and that he had been diagnosed of Retinitis Pigmentosa. They were diagnosed of CHM with an undescribed mutation in the CHM gene c.1083_1084dupT (p.L362Sfs*56) at the Xp21.2 location. We present the patients and the carriers follow‐up. Results: During 8 years one of the patients had a progressive loss of VA. He presented a high myopic refraction and retinal changes that could be related to both conditions. His macular function decreased during the years with loss of retinal sensitivity evaluated by MAIA microperimetry, with Multifocal ERG showing a marked diminution on the central peak. His cousin has not presented important changes during the follow‐up time, preserving macular sensitivity and central visual field. Both mothers show a different AF pattern, with one geographic pattern and another sparse mottled on periphery. Carriers have not changed during these 8 years, neither in their retinal function nor in the anatomical findings. Conclusions: Evolution in CHM disease could differ in patients affected by the same mutation. Myopic defect may increase the retinal damage, with a more aggressive evolution.