Ocular albinism with mutation in GPR143: Findings in wide-field autofluorescence and optical coherence tomography. / Albinismo ocular con mutación en GPR143: hallazgos en autofluorescencia de campo amplio y tomografía de coherencia óptica.

ABSTRACT

A 12 year-old boy who consulted due to nystagmus and low vision from birth. His mother also consulted for low vision of the right eye since she was a child, which worsened recently. The physical examination revealed no alterations in skin and hair pigmentation. In the examination of the anterior segment of the child, areas of slight circumferential hypopigmentation were observed in the iris in both eyes. The fundus examination revealed a choroidal fundus due to the absence of melanin in the retinal pigment epithelium. In the autofluorescence, an absence of physiological macular hypo-autofluorescence was observed and, in optical coherence tomography, foveal hypoplasia was observed in both eyes. In the ocular fundus examination of the mother, slight macular pigmentary changes were observed in the right eye, with hyperpigmented radiated spots in the retinal periphery of both eyes, which were hypo-autofluorescent in the wide-field autofluorescence. In the optical coherence tomography of the right eye, a cavitation of the outer retinal layers was observed in the fovea. The genetic study by nucleotide sequencing was performed on the mother and the child. In the mutation found in the GPR143 gene, the son was hemizygous and the mother was heterozygous. X-linked ocular albinism was diagnosed and the genetic counselling was carried out. Ocular albinism linked to X is the most frequent genetic variant of this disease. Peripheral pigment alterations in heterozygous mothers have been previously described in the literature, but there are no reports of cavitations in the external retinal layers using optical coherence tomography.