Ocular Involvement in Infantile Cystinosis: A Case Report.

Infantile cystinosis is a rare systemic hereditary disorder characterized by abnormal cystine accumulation in cells, leading to various complications. Ophthalmological involvement is one of the major complications of this condition and significantly impacts visual prognosis. We report the case of a five-year-old male patient who was followed up for growth retardation, rickets, and refractory metabolic acidosis and was referred to ophthalmology for severe photophobia. Ophthalmological examination revealed a corrected visual acuity of 4/10 in the right eye and 8/10 in the left eye. Biomicroscopic examination showed birefringent corneal and conjunctival deposits. The diagnosis of infantile cystinosis was confirmed. Cystinosis is a lysosomal, autosomal recessive disease caused by intralysosomal cystine accumulation, manifesting ophthalmologically as cystine keratopathy and, less commonly, cystine retinopathy, which can threaten visual prognosis. The specific treatment for this condition is cysteamine, but management is multidisciplinary and must be initiated early to prevent severe complications.