Is cloudiness a symptom in patients with Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD)?

Is Cloudiness a Symptom in MOGAD?

Yes, cloudiness of vision is a common symptom in MOGAD, occurring as part of the severe visual deficits that characterize MOG-associated optic neuritis.

Visual Symptoms in MOGAD Optic Neuritis

MOGAD-associated optic neuritis characteristically causes severe central visual deficits or complete blindness during acute episodes, which patients often describe as "cloudiness," blurred vision, or loss of clarity. 1, 2

Typical Visual Presentations

• Severe visual deficit or blindness occurs during or after acute episodes, with bilateral involvement being common 1, 2
• Prominent papilledema, papillitis, or optic disc swelling is the hallmark finding on fundoscopy, which contributes to the cloudy vision patients experience 1
• Central vision is primarily affected rather than peripheral vision, causing the characteristic "cloudy" or "foggy" visual experience 1

Acute Clinical Features

• Bilateral simultaneous optic neuritis is common, affecting central rather than peripheral vision 1
• Severe optic nerve head edema can occur, which directly impairs visual clarity 3
• The optic nerve involvement is typically longitudinally extensive, affecting more than 50% of the pre-chiasmal optic nerve length 1

Distinguishing Characteristics

Why Cloudiness Occurs

• The longitudinally extensive pattern of optic nerve inflammation in MOGAD primarily affects central visual pathways, causing diffuse visual clouding rather than specific field defects 1
• Perioptic gadolinium enhancement (optic nerve sheath involvement) occurs frequently, contributing to the visual disturbance 1, 4

Clinical Caveat

• Unlike conditions causing peripheral vision loss first (such as glaucoma), MOGAD presents with acute central vision loss and cloudiness, which is a key distinguishing feature 1
• The cloudiness typically develops acutely over days, not gradually, and is often accompanied by eye pain with movement 4

Treatment Response

• MOGAD optic neuritis appears to be largely responsive to corticosteroids, with dramatic improvement in visual cloudiness often seen after intravenous pulse steroids 4, 3
• High-dose intravenous methylprednisolone is first-line for acute attacks, with plasma exchange or immunoadsorption initiated early if steroids fail 2

Important Clinical Pitfall

• Relapses are common, particularly in the context of early or rapid corticosteroid tapering, and can cause recurrent episodes of visual cloudiness 4, 3
• Slow steroid taper is mandatory due to high risk of flare-ups after rapid cessation 2