Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, USA.
Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
Am J Ophthalmol. 2018 Jun;190:58-68. doi: 10.1016/j.ajo.2018.03.021. Epub 2018 Mar 17.
GUCY2D has been associated with autosomal recessive Leber congenital amaurosis and autosomal dominant cone-rod dystrophy. This report expands the phenotype of autosomal recessive mutations to congenital night blindness, which may slowly progress to mild retinitis pigmentosa.
Retrospective case series.
Multicenter study of 5 patients (3 male, 2 female).
All patients presented with night blindness since childhood. Age at referral was 9-45 years. Length of follow-up was 1-7 years. Best-corrected visual acuity at presentation ranged from 20/15 to 20/30 and at most recent visit averaged 20/25. No patient had nystagmus or high refractive error. ISCEV standard electroretinography revealed nondetectable dark-adapted dim flash responses and reduced amplitude but not electronegative dark-adapted bright flash responses with similar waveforms to the reduced-amplitude light-adapted single flash responses. The 30 Hz flicker responses were relatively preserved. Macular optical coherence tomography revealed normal lamination in 3 patients, with abnormalities in 2. Goldmann visual fields were normal at presentation in children but constricted in 1 adult. One child showed loss of midperipheral fields over time. Fundus appearance was normal in childhood; the adult had sparse bone spicule-like pigmentation. Full-field stimulus testing (FST) revealed markedly decreased retinal sensitivity to light. Dark adaptation demonstrated lack of rod-cone break. Two patients had tritanopia. All 5 had compound heterozygous mutations in GUCY2D. Three of the 5 patients harbor the Arg768Trp mutation reported in GUCY2D-associated Leber congenital amaurosis.
Autosomal recessive GUCY2D mutations may cause congenital night blindness with normal acuity and refraction, and unique electroretinography. Progression to mild retinitis pigmentosa may occur.
GUCY2D 与常染色体隐性遗传莱伯先天性黑矇和常染色体显性圆锥-杆营养不良有关。本报告将常染色体隐性突变的表型扩展为先天性夜盲症，其可能缓慢进展为轻度视网膜色素变性。
回顾性病例系列。
对 5 名患者（3 名男性，2 名女性）进行多中心研究。
所有患者均自幼出现夜盲症。就诊年龄为 9-45 岁。随访时间为 1-7 年。就诊时最佳矫正视力范围为 20/15 至 20/30，最近一次就诊时平均为 20/25。无患者有眼球震颤或高度屈光不正。ISCEV 标准视网膜电图显示暗适应暗闪光反应无法检出，暗适应明闪光反应幅度降低，但与光适应单闪光反应幅度降低的波形相似。30Hz 闪烁反应相对保留。黄斑光学相干断层扫描显示 3 名患者的分层正常，2 名患者存在异常。儿童就诊时的 Goldmann 视野正常，但 1 名成人的视野受限。1 名儿童随时间推移出现中周视野丧失。儿童期眼底外观正常；成人有稀疏的骨刺样色素沉着。全视野刺激测试（FST）显示视网膜对光的敏感性明显降低。暗适应显示缺乏视杆-视锥转换。2 名患者有色盲。所有 5 名患者均在 GUCY2D 中存在复合杂合突变。5 名患者中有 3 名携带与 GUCY2D 相关的莱伯先天性黑矇报道的 Arg768Trp 突变。
常染色体隐性 GUCY2D 突变可能导致先天性夜盲症，视力和屈光度正常，并具有独特的视网膜电图。可能进展为轻度视网膜色素变性。
