Inborn Errors of Metabolism: Refsum Disease

Area of Science:

• Ophthalmology
• Medical Genetics
• Neuro-ophthalmology

Background:

• Refsum disease is a rare autosomal recessive metabolic disorder.
• It is characterized by the accumulation of phytanic acid due to mutations in the PHYH gene.
• Phytanic acid accumulation leads to various systemic manifestations, including neurological and ocular abnormalities.

Purpose of the Study:

• To describe the ocular manifestations in a patient with Refsum disease.
• To highlight the progressive nature of retinal degeneration and vision loss.
• To document associated visual field defects and pupillary abnormalities.

Main Methods:

• Clinical examination of the patient.
• Funduscopy to assess retinal changes.
• Visual acuity and visual field testing.
• Assessment of pupillary light reflex.

Main Results:

• The patient presented with nyctalopia (night blindness).
• Fundus examination revealed progressive panretinal degeneration.
• Gradual decrease in visual acuity and progressive peripheral constriction of the visual field were observed.
• The patient's pupils showed poor dilation in response to light stimulation.

Conclusions:

• Refsum disease significantly impacts retinal function, leading to progressive vision loss.
• Ocular findings include panretinal degeneration, visual field defects, and impaired pupillary response.
• Early recognition of these ophthalmic signs is crucial for managing Refsum disease.