RA is associated with a number of conditions that affect the eyes, including scleritis, keratitis, and keratoconjunctivitis associated with secondary Sjögren’s syndrome. Eye involvement in RA is relatively common. In one study of 691 patients with RA, 27% had some sort of inflammatory eye involvement.1
Understanding eye involvement in RA
Each of the eye disorders or diseases that occur in patients with RA results from inflammation that affects a different part of the eye, with symptoms including pain, dry eye, and sensitivity to light.
Scleritis usually occurs in RA patients with advanced disease who have other extra-articular manifestations, such as vasculitis with skin rash (purpura) and ulcerations and neurologic complications. One quarter of all cases of scleritis occur in patients with RA. Scleritis is an inflammatory condition affecting the white part of the eye (the sclera). The condition is associated with pain in the area of the eye that can radiate to the face and scalp. Pain may be worse at night and may be associated with headache. Scleritis can also be associated with light sensitivity and tearing.2 Episcleritis, which can also occur with RA, is an inflammation of the membrane which covers the white part of the eye.
Choice of treatment of scleritis depends on the severity of inflammation and whether there is danger of loss of sight. Local treatments are not effective. Typically scleritis is treated with oral non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, and immunosuppressive drugs.2
Keratitis is an inflammatory condition that affects the cornea, the clear membrane that covers the iris (the colored part of the eye) and pupil. In keratitis, the cornea may become ulcerated, thin, and opaque, and occasionally perforated. Keratitis is often seen in RA patients who have active scleritis, but can be seen on its own as well.2
Keratitis requires treatment similar to scleritis. Local treatments are not effective. Choice of treatment depends on the severity of inflammation, with options including oral non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, and immunosuppressive drugs.2
Keratoconjunctivitis is the most common eye complication in patients with RA and involves a change in the volume and quality of tears produced by the lacrimal glands, resulting in chronic dry eyes. Keratoconjunctivitis is associated with Sjögren’s syndrome secondary to RA. Secondary Sjögren’s syndrome is a common extra-articular manifestation of RA that affects an estimated 4% to 31% of patients. Many more RA patients may have symptoms of Sjögren’s syndrome, but do not satisfy the diagnostic criteria for the disease. Sjögren’s syndrome is also associated with a reduction in the production of saliva, resulting in dry mouth. Dryness affecting the eyes is sometimes referred to as keratoconjunctivitis sicca (KCS, for short) and dryness affecting the mouth is sometimes referred to as xerostomia .3,4
One study found that RA patients with secondary Sjögren’s syndrome had distinct features that set them apart from those with RA alone. They tended to have higher RA disease activity as measured by disease activity scores (DAS) and more severe arthritis, with a greater number of swollen, tender, and deformed joints. They also tended to be older and have had RA for a longer period of time. Patients with RA and secondary Sjögren’s syndrome appeared to have a stronger hereditary component to their disease, with a clearer history of autoimmune disease in their families. Patients with RA and secondary Sjögren’s syndrome had a distinct profile in terms of presence of certain antibodies, with patients with both diseases tending to be rheumatoid factor (RF)-positive, as well as positive for other auto-antibodies (SSA and SSB). Patients with the RA and Sjögren’s combination were also more likely to have blood abnormalities, including decreased numbers of platelets (thrombocytopenia) and decreased numbers of red blood cells (anemia). Interstitial lung disease, a common lung complication associated with RA, was more likely to be found in RA patients with secondary Sjögren’s syndrome.3
Treatment for keratoconjunctivitis may vary from patient to patient, but will typically involve relief of dryness symptoms using artificial tear products. NSAIDs, such as ibuprofen, glucocorticoids, and disease-modifying anti-rheumatic drugs (DMARDs), such as methotrexate, may be used to address the inflammatory process involved in keratoconjunctivitis.