LEBER CONGENITAL AMAUROSIS WITH LARGE RETINAL PIGMENT CLUMPS CAUSED BY COMPOUND HETEROZYGOUS MUTATIONS IN KCNJ13. Issue Volume 11:Issues 3(2017:Summer) (2017)

• Record Type: Journal Article
• Authors: Perez-Roustit, Sarah; Marquette, Virginie; Bocquet, Béatrice; Kaplan, Josseline; Perrault, Isabelle; Meunier, Isabelle; Hamel, Christian P.
• Is Part Of: Retinal cases & brief reports. Volume 11:Issues 3(2017:Summer)
• Publication Date: 2017
• Subjects: Leber congenital amaurosis -- KCNJ13 -- retinal pigment deposits; Retina -- Diseases -- Periodicals; Retina -- Periodicals; Retinal Diseases -- Periodicals; Retina -- Case Reports; Retinal Diseases -- Case Reports; 617.7
• DOI: 10.1097/ICB.0000000000000326
• Languages: English
• ISSNs: 1935-1089

Abstract

Abstract : Purpose: To describe a patient with mutations in KCNJ13 presenting particular clinical features. Methods: Standard ophthalmic examination, fundus autofluorescence, spectral domain optical coherence tomography, full-field electroretinography. The 3 exons of KCNJ13 were polymerase chain reaction amplified and Sanger sequenced. Patients: A 31-year-old man with Leber congenital amaurosis. Results: Patient had nystagmus since childhood, best-corrected visual acuity limited to 20/400 OD and 20/200 OS, and had cataracts extracted in both eyes. There were clumpy pigment deposits mostly in macular area, causing an uneven line of retinal pigment epithelium on spectral domain optical coherence tomography. In retinal parts devoid of pigment deposits around the optic disk and in periphery, retinal thickness was increased and hyperreflective formations were present either in the inner nuclear layer or in the outer nuclear layer. The patient was compound heterozygous for new mutations in KCNJ13 which encodes the Kir 7.1 potassium channel, c.314G>T (p.Ser105Ile) in exon 2 and c.655C>T (p.Gln219*) in exon 3. Both mutations were absent from databases. Conclusion: KCNJ13 mutations are responsible for early-onset retinal dystrophy, featuring remarkable clumpy pigment deposits at the level of the retinal pigment epithelium, suggesting dysfunction and disorganization of this tissue. Parts of the retina remain relatively preserved anatomically but are increased in thickness. This distinct fundus appearance should help in identifying the " KCNJ13 retinal dystrophy" to orient the molecular diagnosis. Abstract : We report on a case of Leber congenital amaurosis with new compound heterozygous mutations in KCNJ13 showing characteristic clumpy pigment deposits at the retinal pigment epithelium level and a thickened retina in spared areas around the optic disk and in the periphery.