Systemic Lupus Erythematosus (SLE) is a chronic autoimmune condition where the immune system incorrectly attacks healthy tissue, leading to widespread inflammation and potential damage across multiple organ systems. Because SLE is systemic, it can affect virtually any part of the body, including the delicate structures of the eye. Lupus can cause a variety of significant eye problems, ranging from mild irritation to severe, sight-threatening complications. Ocular involvement affects up to one-third of SLE patients and can sometimes be the first sign of the disease.
The Autoimmune Mechanism of Ocular Damage
The primary pathology driving lupus-related eye problems is the deposition of immune complexes within the small blood vessels of the eye. These complexes trigger an inflammatory response and activate the complement cascade, leading to vasculitis (inflammation of the blood vessel walls). The resulting inflammation damages the endothelial cells and causes microvascular thrombosis (tiny blood clots).
This damage restricts blood flow, leading to localized ischemia (lack of oxygen) and the breakdown of the blood-retinal barrier. This autoimmune attack and resulting vasculopathy cause the specific symptoms seen throughout the eye.
Lupus Effects on the Eye’s Surface and Mid-Layer
Keratoconjunctivitis sicca, or Dry Eye Syndrome, is the most frequently reported ocular manifestation, affecting approximately 25% of SLE patients. This condition results from the autoimmune attack targeting the lacrimal glands responsible for tear production, often leading to a secondary diagnosis of Sjögren’s syndrome. Symptoms range from a gritty sensation and mild irritation to severe pain due to corneal surface damage.
Inflammation can also affect the white outer layer of the eye, causing episcleritis or scleritis. Episcleritis involves the surface layer of the sclera and presents with a red eye and mild discomfort, often managed with topical treatment. Scleritis is a deeper, painful inflammation of the sclera itself that can lead to thinning or necrosis of the eyeball wall, requiring aggressive systemic immunosuppression. Severe surface inflammation or profound dryness can damage the cornea, causing recurrent erosions or peripheral ulcerative keratitis, which signals active systemic vasculitis.
Lupus Effects on the Retina and Optic Nerve
The posterior segment of the eye, including the retina and optic nerve, is susceptible to the most sight-threatening complications of SLE. Lupus Retinopathy is the most common posterior segment finding, increasing significantly during periods of active systemic disease. This condition is caused by underlying vasculitis and microvascular blockages in the retinal blood vessels.
The lack of blood flow results in characteristic findings such as “cotton wool spots” (areas of nerve fiber layer damage) and intraretinal hemorrhages. These vascular changes range from mild findings to severe vaso-occlusive disease where larger retinal vessels become blocked. Such occlusions, especially with antiphospholipid antibodies, are medical emergencies that can lead to permanent vision loss and proliferative retinopathy (abnormal new blood vessels).
Optic Neuritis, or inflammation of the optic nerve, is another severe manifestation causing sudden and potentially profound vision loss. Inflammation or ischemic damage disrupts the optic nerve’s ability to transmit visual signals to the brain. While some cases respond to high-dose corticosteroids, the severity of the initial damage dictates the final visual outcome. Retinal and optic nerve involvement often signals high systemic disease activity and may precede a lupus diagnosis.
Ocular Monitoring Due to Lupus Medications
Beyond the direct effects of the disease, certain long-term medications used to manage SLE require careful ocular monitoring. Hydroxychloroquine (Plaquenil) is a commonly prescribed anti-malarial drug that carries a risk of retinotoxicity (damage to the retina). This toxicity is related to the cumulative dose and duration of use, with the risk increasing after five years of therapy.
Patients require a baseline eye examination to document retinal health before treatment begins. Annual screening is recommended, typically starting after five years of continuous use, unless the patient has risk factors like high daily dosage or kidney impairment. Screening utilizes specialized imaging tests to detect structural changes and reduced visual sensitivity:
- Spectral-Domain Optical Coherence Tomography (SD-OCT)
- Fundus autofluorescence (FAF)
- Automated visual field testing, particularly for the central visual field
Early detection is important because the damage can progress even after the medication is stopped if it reaches an advanced stage.