Rheumatoid Arthritis: Keratitis Sicca
The green spots on the cornea represent fluorescein staining of devitalized epithelium in an eye that does not make tears.
Corneal and conjunctival drying is found in 25% of patients with rheumatoid arthritis, more commonly in the severe forms. Lymphocytic infiltration destroys the tear-forming glands.
The patient experiences a foreign body sensation and blurred vision. Fluorescein dye applied to the cornea usually discloses green punctate staining of de-epithelialized areas. If the drying is severe, the cornea may become permanently scarred.
These findings, called the "keratitis sicca" syndrome, are also found in other connective tissue diseases, especially Sjögren's syndrome and scleroderma.
To check out the common ophthalmic manifestations of the various connective tissue diseases, select Common Ophthalmic Manifestations of Rheumatic Diseases.
This process occurs in the most severe forms of rheumatoid arthritis that are often accompanied by vasculitis. The pathogenesis may be ischemia.
What to do?
The diagnosis of a tear deficiency syndrome is made formally by the Schirmer Test. A standard filter strip is hinged in the lateral conjunctival cul-de-sac and the extent of wetting of the strip is measured after five minutes. Less than 3 mm of wetting is considered diagnostic of tear deficiency.
Apart from rheumatoid arthritis and Sjögren's Syndrome, other causes of tear deficiency are ocular irradiation, cicatricial pemphigoid and conjunctival trauma.
Treatment consists of instilling artificial tears. The viscous preparations are most useful in severe cases. Tears may also be conserved by occluding the puncta, the eyelid orifices of the drainage system.
Sclerokeratitis is very difficult to treat. Antimetabolites used in advanced connective tissue illnesses are the preferred method.