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Sjögren's
syndrome is characterized by excessive dryness of the eyes, mouth,
and other mucous membranes.
Sjögren's syndrome is thought to be an autoimmune disorder, but its cause is not known. It is more common among women than men. Some people with Sjögren's syndrome also have other autoimmune disorders, such as rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, vasculitis, mixed connective tissue disease, Hashimoto's thyroiditis, primary biliary cirrhosis, and chronic autoimmune hepatitis.
White blood cells infiltrate the glands that secrete fluids, such as the salivary glands in the mouth and the tear glands in the eyes. The white blood cells injure the glands, resulting in a dry mouth and dry eyes—the hallmark symptoms of this syndrome.
Symptoms
In some people, only the mouth or eyes are dry (a condition called sicca complex or sicca syndrome). Dryness of the eyes may severely damage the cornea, resulting in a scratchy or irritated sensation, and a lack of tears can cause permanent eye damage. Insufficient saliva in the mouth can dull taste and smell, make eating and swallowing painful, and can cause cavities. The salivary glands in the cheeks (parotids) become enlarged and slightly tender in about one third of people. The mouth may also burn, which may sometimes indicate a complicating yeast infection.
In other people, many organs are affected. Sjögren's syndrome can dry out the mucous membranes lining the digestive tract, windpipe (trachea), vulva, and vagina. Dryness of the vulva and vagina can make sexual intercourse difficult. Dryness of the trachea can cause cough. The protective sac surrounding the heart (pericardium) may be inflamed—a condition called pericarditis. Nerve, lung tissue, and other tissues may be damaged by the inflammation.
Joint inflammation (arthritis) occurs in about one third of people, affecting the same joints that rheumatoid arthritis affects, but the joint inflammation of Sjögren's syndrome tends to be milder and is usually not destructive. Lymph nodes may enlarge throughout the body. Lymphoma, a cancer of the lymphatic system, is more common among people who have Sjögren's syndrome than the general population. Skin rashes, kidney damage, Raynaud's syndrome, and vasculitis that causes damage to the peripheral nerves may occur.
Diagnosis
Although a sensation of dry mouth or dry eyes is fairly common, a sensation of dry mouth and dry eyes accompanied by joint inflammation may indicate that the person has Sjögren's syndrome. Various tests can help a doctor diagnose this disorder and differentiate it from other disorders that can cause similar symptoms.
The amount of tears produced can be estimated by placing a filter paper strip under each lower eyelid and observing how much of the strip is moistened (Schirmer's test). A person who has Sjögren's syndrome may produce less than one third of the normal amount. An ophthalmologist can test for damage to the eye's surface. More sophisticated tests to evaluate salivary gland secretion may be performed, and a doctor may order scans or the removal of tissue for examination and testing (biopsy) of the salivary glands.
Blood tests can detect abnormal antibodies, including SS-A, an antibody that is present in Sjögren's syndrome. Antinuclear antibodies (which are found in people with lupus) and rheumatoid factor (which is found in people with rheumatoid arthritis) can also be found in people with Sjögren's syndrome. The erythrocyte sedimentation rate (ESR), a test that measures the rate at which red blood cells settle to the bottom of a test tube containing blood, is elevated in about 7 of 10 people. About 1 of 3 people has a decreased number of red blood cells (anemia), and 1 in 4 people has a decreased number of certain types of white blood cells (leukopenia).
Prognosis and
Treatment
The prognosis is generally good. However, if the lungs, kidneys, or lymph nodes are damaged by the antibodies, pneumonia, kidney failure, or lymphoma may result.
No cure for Sjögren's syndrome is available, but symptoms can be relieved. Dry eyes can be treated with artificial tear drops during the day and a lubricating ointment at night. A prescription eye drop containing cyclosporine can also be used. Shields can be fitted on the sides of glasses, helping to protect the eyes from air and wind, reducing evaporation of tears. A simple surgical procedure called punctal occlusion can be performed. In this procedure, an ophthalmologist inserts small plugs into the tear ducts in the corner of the lower eyelid, so the person's tears stay on the eye longer.
A dry mouth can be moistened by continuously sipping liquids, chewing sugarless gum, or using a saliva substitute mouth rinse. Drugs that reduce the amount of saliva, such as decongestants, antidepressants, and antihistamines, should be avoided because they can worsen the dryness. The drug pilocarpine or cevimeline may help stimulate the production of saliva if the salivary glands are not too severely damaged.
Fastidious dental hygiene and frequent dental visits can minimize tooth decay and loss. Painful, swollen salivary glands can be treated with analgesics and warm compresses. Because joint symptoms are usually mild, treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) and rest is often sufficient. Antimalarial drugs (such as hydroxychloroquine) can relieve joint pain, swollen lymph nodes, and skin problems. Very rarely, the drug methotrexate may be given. When symptoms resulting from damage to internal organs are severe, corticosteroids (such as prednisone) or cyclophosphamide taken by mouth can be useful.
Sjögren's syndrome that occurs along with other autoimmune diseases, such as lupus, rheumatoid arthritis, and systemic sclerosis, is referred to as secondary Sjögren's syndrome. People with secondary Sjögren's syndrome receive additional treatment for the other disease.
Last full review/revision February 2008 by Rula A. Hajj-Ali, MD
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