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Home > What Is Cystinosis? > How Does Cystinosis Affect Eyes?

How Does Cystinosis Affect Eyes?

People with cystinosis do not have the ability to transport cystine out of their cells. This leads to the formation of crystals within the corneas of their eyes. This can cause a condition called photophobia because the eyes are very sensitive to light. Other effects include eye pain, damage to the corneas, vision problems (eg, haziness), foreign body sensation, squinting, band keratopathy, and blepharospasm (involuntary eye closure).1-3

Diagnosis can be made with an ophthalmic exam.2

References: 1. Kaiser-Kupfer MI, Fujikawa L, Kuwabara T, Jain S, Gahl WA. Removal of corneal crystals by topical cysteamine in nephropathic cystinosis.
N Engl J Med. 1987;316:775-779. 2. Gahl WA, Kuehl EM, Iwata F, Lindblad A, Kaiser-Kupfer MI. Corneal crystals in nephropathic cystinosis: natural history and treatment with cysteamine eyedrops. Mol Genet Metab. 2000;71:100-120. 3. Tsilou E, Zhou M, Gahl W, Sieving PC, Chan CC. Ophthalmic manifestations and histopathology of infantile nephropathic cystinosis: report of a case and review of the literature. Surv Ophthalmol. 2007;52:97-105.


CYSTARAN is a cystine-depleting agent indicated for the treatment of corneal cystine crystal accumulation in patients with cystinosis.

Important Safety Information:

The most frequently reported ocular adverse reactions occurring in ≥10% of patients were sensitivity to light, redness, eye pain/irritation, headache, and visual field defects.