J Korean Ophthalmol Soc.  2017 May;58(5):616-619. 10.3341/jkos.2017.58.5.616.

Ocular Findings in Mucolipidosis Type II

• Suh SY
• Cheon CK
• Jung JH

• KMID: 2378636
• DOI: http://doi.org/10.3341/jkos.2017.58.5.616

Abstract

PURPOSE
To report ocular findings of a mucolipidosis type II patient with novel mutation.
CASE SUMMARY
A 10-year-old boy visited our pediatric genetic metabolic clinic for evaluation of his overall developmental delay and short stature. The boy was diagnosed with mucolipidosis type II (I-cell disease) using plasma enzyme assay and DNA sequencing of the GNPTAB gene mutation. An ophthalmologic investigation was then performed, and a depressed nasal bridge, broad nose, and swelling in the upper lid of both eyes were noted. The best corrected visual acuity was 0.32 and 0.1 and the intraocular pressure was 35 mmHg and 24 mmHg in the right and left eyes, respectively. The anterior chamber angles of both eyes were normal and mild cornea opacity in both eyes was observed. Fundus examination revealed retinal atrophy with folds in both eyes, as well as optic disc edema and optic atrophy in the right and left eyes, respectively. Atherosclerotic changes in the retinal vessels and cystoid macular edema in the left eye were observed, and ocular ultrasound revealed increased posterior sclera thickness in both eyes.
CONCLUSIONS
Ocular manifestations of mucolipidosis type II are not currently well-known, and differentiation from other metabolic disorders may be difficult. An ophthalmic work-up can assist in diagnosis, and regular ophthalmic examinations should be used to maintain visual function in mucolipidosis patients.

Keyword

Cystoid macular edema; Lysosomal storage disease; Mucolipidosis; Retinal atrophy

MeSH Terms

Anterior Chamber
Atrophy
Child
Cornea
Diagnosis
Edema
Enzyme Assays
Humans
Intraocular Pressure
Lysosomal Storage Diseases
Macular Edema
Male
Mucolipidoses*
Nose
Optic Atrophy
Plasma
Retinal Vessels
Retinaldehyde
Sclera
Sequence Analysis, DNA
Ultrasonography
Visual Acuity
Retinaldehyde

Figure

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  Figure 1 Photograph of the patient's face. Depressed nasal bridge and upper eyelid swelling in both eyes were observed.

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  Figure 2 The fundus photographs and the optical coherence tomography of the patient. (A) Fundus examination of the both eyes showed retinal atrophy with retinal fold (white arrow). Optic disc edema in right eye and optic disc atrophy in left eye were observed. Left eye showed retinal artery narrowing with atherosclerotic changes (black arrows) and cystoid macular edema. (B) The optical coherence tomography showed cystoid macular edema in left eye.

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