Can blurred vision be a symptom of interstitial lung disease (ILD) or sarcoidosis, or both?

Blurred Vision in Sarcoidosis and Interstitial Lung Disease

Blurred vision is a common ocular manifestation of sarcoidosis but is not typically associated with interstitial lung disease (ILD) unless the ILD is specifically caused by sarcoidosis. 1, 2

Ocular Manifestations in Sarcoidosis

Sarcoidosis frequently affects the eyes, with ocular involvement occurring in approximately 30-50% of patients with systemic sarcoidosis 2, 3. The eye is the second most commonly affected organ after the lungs in sarcoidosis patients 2.

Common ocular manifestations in sarcoidosis include:

• Uveitis - inflammation of the uveal tract (iris, ciliary body, and choroid) that commonly causes blurred vision 1, 3
• Episcleritis/scleritis - inflammation of the episclera or sclera 4, 1
• Conjunctival nodules or granulomas 1
• Optic neuropathy - can cause significant vision loss 5
• Lacrimal gland enlargement 3
• Retinal vasculitis 5

Mechanism of blurred vision in sarcoidosis:

• Granulomatous inflammation affecting various parts of the eye
• Secondary complications such as cataracts and glaucoma from chronic inflammation or treatment side effects 3
• Direct involvement of the optic nerve 5

Interstitial Lung Disease and Vision

ILD by itself does not typically cause blurred vision unless:

1. The ILD is specifically caused by sarcoidosis
2. The ILD is part of a systemic condition that also affects the eyes (e.g., connective tissue diseases like scleroderma or rheumatoid arthritis) 4
3. Medications used to treat ILD cause ocular side effects

The American Thoracic Society guidelines on ILD do not mention blurred vision as a direct manifestation of non-sarcoid ILD 4.

Diagnostic Considerations

When a patient presents with blurred vision and known or suspected ILD:

1. Determine if sarcoidosis is the underlying cause of ILD:

   • Look for bilateral hilar lymphadenopathy on chest imaging 1
   • Consider elevated ACE levels (present in 60-83% of sarcoidosis patients) 1
   • Evaluate for other systemic manifestations of sarcoidosis

2. Comprehensive ophthalmologic examination to identify:

   • Uveitis (anterior, intermediate, posterior, or panuveitis)
   • Retinal vasculitis
   • Optic nerve involvement
   • Conjunctival nodules

3. Consider other systemic diseases that can cause both ILD and ocular manifestations:

   • Connective tissue diseases (scleroderma, rheumatoid arthritis) 4
   • Vasculitides 4

Management Implications

The presence of blurred vision in a patient with ILD should prompt:

1. Urgent ophthalmologic referral - ocular sarcoidosis can be sight-threatening if not treated promptly 1, 3

2. Systemic evaluation for sarcoidosis if not already diagnosed:

   • Chest imaging
   • Serum ACE levels
   • Consider biopsy of accessible tissues showing granulomatous inflammation

3. Treatment considerations:

   • Topical steroids for anterior uveitis 6
   • Systemic corticosteroids for posterior uveitis or other significant ocular involvement 1
   • Immunomodulatory therapy including anti-TNF agents for resistant cases 4, 1

Clinical Pearls and Pitfalls

• Pearl: Ocular involvement may be the initial manifestation of sarcoidosis in many patients, preceding pulmonary or other systemic findings 7
• Pitfall: Failing to perform systematic eye examinations in patients with sarcoidosis can lead to delayed diagnosis and treatment of potentially sight-threatening conditions 7
• Pearl: The frequency and course of ocular sarcoidosis vary with age, race, and geography 6
• Pitfall: Anti-TNF treatments used for sarcoidosis can paradoxically cause inflammatory skin conditions but are generally beneficial for ocular manifestations 4, 1

In summary, when evaluating a patient with ILD and blurred vision, sarcoidosis should be high on the differential diagnosis, as it commonly affects both the lungs and eyes. Other systemic conditions that can cause both ILD and ocular manifestations should also be considered.