Sympathetic Uveitis
Definition
A rare bilateral granulomatous panuveitis that develops in the uninjured (sympathizing) eye following penetrating trauma or surgery to the fellow (exciting) eye, mediated by autoimmune sensitization to uveal antigens.
Clinical Snapshot
Sympathetic ophthalmia (SO) is a rare but devastating bilateral granulomatous panuveitis that develops in the uninjured (sympathizing) eye following penetrating trauma or intraocular surgery to the fellow (exciting) eye. It is caused by autoimmune sensitization to uveal and retinal antigens exposed by the injury. The onset is typically 2 weeks to 3 months after the inciting event, though cases have been reported years later. Enucleation of the exciting eye within 2 weeks of injury may prevent SO, but this decision requires careful individualized consideration — particularly when the exciting eye retains visual potential.
Epidemiology
SO is rare — it occurs in approximately 0.2–0.5% of penetrating ocular injuries and 0.01% of intraocular surgeries. The risk is higher with injuries involving uveal prolapse and retained intraocular foreign bodies. It can occur after any intraocular surgery, including vitreoretinal surgery and cataract surgery.
Pathophysiology
Penetrating trauma or surgery exposes uveal and retinal antigens (particularly retinal S-antigen and interphotoreceptor retinoid-binding protein) to the immune system. T-cell–mediated autoimmunity is sensitized to these antigens, which are then attacked in both eyes — the exciting eye (already injured) and the sympathizing eye (previously uninjured). The histopathological hallmark is diffuse granulomatous inflammation of the uveal tract with Dalen-Fuchs nodules (aggregates of epithelioid cells between the RPE and Bruch's membrane).
Risk Factors
- Penetrating ocular trauma (the primary risk factor)
- Uveal prolapse at the time of injury
- Retained intraocular foreign body
- Intraocular surgery (vitreoretinal, cataract, glaucoma)
- Multiple intraocular surgeries
Clinical Presentation
Bilateral granulomatous panuveitis developing weeks to months after penetrating trauma or surgery. The sympathizing eye develops: anterior chamber cells and flare, mutton-fat KPs, posterior synechiae, vitritis, disc edema, and multifocal choroidal infiltrates (Dalen-Fuchs nodules). The exciting eye shows similar findings superimposed on the original injury. Systemic features resembling VKH disease (headache, tinnitus, dysacusis, vitiligo, poliosis) may occur.
Diagnostic Pearls
- A history of penetrating ocular trauma or intraocular surgery is essential for the diagnosis — SO does not occur without an inciting event.
- The onset is typically 2 weeks to 3 months after the inciting event — but cases have been reported years later.
- Dalen-Fuchs nodules (yellow-white subretinal deposits) are the pathognomonic fundoscopic finding.
- SO is clinically and histopathologically similar to VKH disease — the history of trauma is the key distinguishing feature.
Differential Diagnosis
- Vogt-Koyanagi-Harada disease (no history of trauma)
- Sarcoidosis (systemic features, no trauma history)
- Bilateral posterior uveitis (other etiologies)
Evidence-Based Management
Prevention: enucleation of the exciting eye within 2 weeks of injury may prevent SO — this decision must balance the risk of SO against the visual potential of the exciting eye. Once SO has developed, enucleation of the exciting eye does not reliably prevent progression in the sympathizing eye. Treatment: high-dose systemic corticosteroids (prednisone 1–1.5 mg/kg/day) are the cornerstone of treatment. Steroid-sparing immunosuppression (cyclosporine, mycophenolate, azathioprine) for chronic or steroid-dependent disease. The prognosis for the sympathizing eye is generally better than for the exciting eye with aggressive treatment.
Monitoring & Follow-Up
Frequent follow-up during active disease. Long-term follow-up is essential — SO can recur years after apparent remission. Monitor for complications: cataract, glaucoma, CME, and subretinal fibrosis.
Clinical Pearls
- The 2-week window for enucleation is a guideline, not an absolute rule — the decision must be individualized based on the visual potential of the exciting eye.
- Once SO has developed, enucleation of the exciting eye does not reliably prevent progression — the autoimmune process is already established.
- SO is clinically similar to VKH disease — the history of penetrating trauma is the key distinguishing feature.
- Long-term follow-up is essential — SO can recur years after apparent remission, and the risk of late complications (cataract, glaucoma) is significant.
Related Therapeutics — Clinician's Companion
- Oral Therapeutics — Oral Prednisone, Methotrexate, Cyclosporine (Clinician's Companion)
- Anti-inflammatory Rescue — Pred Forte®, Durezol® (Clinician's Companion)
Key References
- 1.Galor A, et al. Sympathetic ophthalmia: incidence of ocular complications and vision loss in the sympathizing eye. Am J Ophthalmol. 2009.
- 2.Chu DS, Foster CS. Sympathetic ophthalmia. Int Ophthalmol Clin. 2002.
This entry is an educational reference designed to support clinical reasoning and awareness. It does not constitute medical advice, establish a standard of care, or replace individualized patient assessment. Clinicians should consult current guidelines and applicable clinical resources when making patient care decisions.