Subclinical optic neuropathy in Fabry disease

Area of Science:

• Ophthalmology
• Genetics
• Neurology

Background:

• Fabry disease is a rare X-linked lysosomal storage disorder caused by alpha-galactosidase A deficiency.
• Ophthalmic manifestations include cornea verticillata, conjunctival aneurysms, and vascular tortuosity.
• Recent evidence suggests a possible subclinical optic neuropathy in Fabry patients.

Purpose of the Study:

• To investigate for signs of optic neuropathy in a cohort of Fabry disease patients.
• To evaluate the utility of automated perimetry in detecting subclinical visual field defects.

Main Methods:

• A pilot study involving 31 Fabry patients (15 male, 16 female) aged 34 years on average.
• Ophthalmological examinations included visual acuity, slit lamp, pupillary reaction, funduscopy, tonometry, and automated perimetry (Humphrey 30-2).
• Most patients (29/31) were receiving enzyme replacement therapy with agalsidase alpha.

Main Results:

• Typical cornea verticillata observed in 25/31 patients; tortuous vessels in 17.
• Pathognomonic 'Fabry' cataracts seen in 2 patients.
• Automated perimetry revealed relative central scotomas in 10/31 patients, indicating pathological visual fields.

Conclusions:

• Subclinical optic neuropathy was identified in 10/31 Fabry disease patients, consistent with prior reports.
• The findings suggest perimetry should be considered in ophthalmological evaluations for Fabry disease.
• No patients reported visual impairment, highlighting the subclinical nature of this complication.