Ocular Cystinosis-Bilateral Corneal Crystals and Macular Atrophy in a Child

Open Access

Abstract

Introduction: Cystinosis is a rare autosomal-recessive lysosomal storage disorder caused by CTNS gene mutations, leading to cystine accumulation in multiple organs. Ocular involvement often precedes systemic disease and provides critical diagnostic clues. Case Presentation: We describe a 7-year-old child presenting with photophobia, bilateral corneal crystals, and visual decline. Slit-lamp examination revealed dense, refractile stromal deposits, while fundus evaluation showed macular atrophy and mild optic disc pallor. Systemic evaluation identified growth retardation and rickets-like deformities, consistent with nephropathic cystinosis. Laboratory and genetic testing confirmed the diagnosis. Discussion: This case emphasizes the correlation between ocular and systemic manifestations in cystinosis. Corneal and retinal findings serve as accessible biomarkers for disease burden and treatment adherence. Early ophthalmic recognition enables timely initiation of cysteamine therapy and systemic management, mitigating renal and skeletal complications. Conclusion: Ocular cystinosis, though rare, offers a unique diagnostic window for systemic disease. Routine slit-lamp screening in children with photophobia or growth failure and interdisciplinary management can significantly improve visual and systemic prognosis.