Abstract
INTRODUCTION: Ocular cystinosis is a rare hereditary lysosomal storage disorder characterized by amino acid cystine deposition in various tissues, prominently affecting the cornea and conjunctiva. While typically diagnosed in childhood, cases in adults may present atypically or as part of the nephropathic spectrum. This report highlights the clinical presentation, diagnosis, and management of ocular cystinosis in a 37-year-old male. CASE PRESENTATION: A 37-year-old male presented with complaints of photophobia and ocular discomfort for a duration of 6 months. On slit-lamp examination, characteristic crystalline deposits were observed in the corneal stroma. Additional findings included mild conjunctival injection. Visual acuity was 6/6 in both eyes. Anterior segment optical coherence tomography demonstrated hyperreflective deposits up to corneal stroma, while specular microscopy revealed a normal endothelial cell count and morphology. Systemic evaluation revealed no signs of cystinosis. The patient was treated with topical cysteamine ophthalmic solution 0.44%, resulting in subjective improvement in photophobia and stabilization of corneal findings over a 6-month follow-up period. CONCLUSION: This case underscores the importance of recognizing ocular manifestations of cystinosis in adult patients, particularly those with no history or signs of systemic involvement. Early and sustained use of topical cysteamine ophthalmic solutions can significantly mitigate symptoms and prevent progression of corneal changes. Comprehensive management necessitates a multidisciplinary approach to address systemic and ocular sequelae of the disease.