Ocular Manifestations of cystinosis Case Report and Review of

Literature DR. MAYUR KULKARNI

DR. H. T. KARAD ; DR. T. R. GITTE ; DR. SUJATA AGRAWAL;

DR. AZEEM MASHAYAK

ABSTRACT

Cystinosis is a rare autosomal recessive metabolic disorder characterized by the

intracellular accumulation of disulfide of the amino acid cysteine, in many organs and

tissues. Infantile nephropathic cystinosis is the most severe phenotype. Although renal

disease is the most prominent feature of the cystinosis, corneal cystine crystal

formation remains a major complication, leading to photophobia, corneal erosions,

and keratopathies . Corneal crystal accumulation and pigmentary retinopathy were

originally the most commonly described ophthalmic manifestations, but successful

kidney transplantation significantly changed the natural history of the disease.

Moreover, the extent of corneal crystal accumulation reflects the course and severity

of the disease itself, and the cornea is accessible to direct examination . As cystinosis

patients now live longer, long-term complications in extra-renal tissues, including the

eye, have become apparent. A case of an adult patient with non-nephropathic

cystinosis is reported. He presented with corneal complications of cystinosis.

CASE REPORT

Here is a case of 63 old male who came to our OPD , Ophthalmology department,

YCRH MIMSR medical college, latur; with complaints of redness , irritation and

watering from left eye since two days which was sudden in onset . He complained of

longstanding photophobia glare and foreign body sensation in his eyes. Past

ophthalmic history included recurrent episodes of same complains five to six times in

previous 10 years. On ocular examination best corrected visual acuity was 6/18 in the

both eyes. Slit-lamp examination revealed normal lids , conjunctival congestion in left

eye, crystal depositions in both eyes throughout the cornea including endothelium.

Both irides were normal. Lens showed grade 1 NS. Funduscopic examination of the

both eyes revealed few details because of hazy cornea.

DISCUSSION

Crystal accumulation in the conjunctiva and cornea is the pathognomonic ophthalmic

manifestation of cystinosis. This was initially described by Bürki in 1941, and has been

observed in all subsequently reported cases. Corneal crystals present as myriad

needle-shaped, highly reflectile opacities easily seen by slit lamp examination. They

appear to be present in the corneal epithelium, stroma and endothelium. Due to their

characteristic appearance and distribution they are easily, with few exceptions

differentiated from other crystalline keratopathies. Accumulation of crystals in the

cornea starts in infancy and is definitely evident by 16 months of age. Deposition

begins in the anterior periphery and proceeds posteriorly and centripetally. By

approximately 7 years of age, the entire peripheral stroma and endothelium

accumulates crystals. By approximately 20 years of age, crystals can be seen in the

entire corneal stroma. Crystal deposition advances more rapidly in the periphery.

Increased density of cystine crystals results in a hazy cornea that is easily recognizable

with the naked eye in older, untreated cystinosis patients. Corneal crystals are initially

asymptomatic, but photophobia can develop within the first few years of life. The

severity of photophobia varies in ambient light but nearly all patients have some

degree of discomfort with bright illumination after the first decade of life. Many

patients require dark glasses in bright illumination and some have significant

blepharospasm. Superficial punctate keratopathy with associated foreign body

sensation and pain is occasionally seen, mostly in patients older than 10 years of age.

Katz et al documented loss of contrast sensitivity, increased glare disability, decreased

corneal sensitivity and increased corneal thickness in patients with nephropathic

cystinosis; he speculated that these changes are the result of cornea crystal

deposition. Corneal crystals do not affect the visual acuity, so decreased visual acuity

should prompt an investigation of other causes.

OPTICAL CUT SECTION OF CORNEA

ANTERIOR SEGMENT OCT

CONCLUSION

We report a case of non-nephropathic cystinosis in a male of 63 years

old with no any other complications of cystinosis. He presented with

long lasting photophobia , glare , foreign body sensation and redness of

left eye. On examination he showed punctate, needle-shaped crystals

diffusely present throughout the cornea . Diagnosis is confirmed on

laboratory testing with an elevated level of serum leukocyte cystine of

2.74 nmol half-cystine/mg protein (Normal range of serum leukocyte

cystine for non-nephropathic cystinosis is 1 to 3 nmol half-cystine/mg

protein)

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