Diagnosing Sjogren’s Syndrome
Rheumatologists at NYU Langone are experienced in diagnosing autoimmune disorders, conditions in which the immune system mistakenly attacks healthy tissues in the body. In Sjogren’s syndrome, the immune system mainly attacks moisture-producing glands: the lacrimal glands, which produce tears and are located in the eyes, and the salivary glands, which produce saliva and are located inside the mouth.
This results in chronic inflammation, which in turn decreases the production of tears and saliva, and leads to dry eye syndrome and dry mouth. It can also lead to dryness in other mucous membranes in the body. When severe, Sjogren’s syndrome affects major organs such as the lungs, brain, or kidneys.
Symptoms of Sjogren’s Syndrome
Eye symptoms may include constant or intermittent dryness, as well as frequent stinging, burning, itching, irritation, or discomfort in bright light. Your eyes may tire easily or have a gritty or sandy sensation, and the tear ducts may become enlarged. Contact lenses may feel less and less comfortable to wear, and strands of mucus may be present in your eyes, especially when you wake up.
Left untreated, dry eyes can damage the epithelial cells that protect the cornea, the transparent, dome-like structure on the front of the eye. This can make the cornea more vulnerable to injury from foreign particles or infections.
People with Sjogren’s syndrome may have inadequate saliva. This can sometimes lead to choking and trouble with chewing or swallowing. Also, because saliva can help kill bacteria and prevent infections, people with Sjogren’s may have rapid tooth decay or recurrent yeast infections in the mouth, known as oral candidiasis or thrush. The salivary glands may become enlarged and firm, either occasionally or chronically, possibly altering the sense of taste.
The vast majority of people with Sjogren’s syndrome are women. Because it affects mucous membranes in the body, women may also notice vaginal dryness.
As occurs in many other autoimmune diseases, people with Sjogren’s syndrome may experience joint pain and swelling, muscle aches, and fatigue. In fact, many people with Sjogren’s syndrome also have fibromyalgia, a condition that causes chronic pain in muscles throughout the body, especially at certain tender points.
Others may also have a condition known as subacute cutaneous lupus, which causes red, scaly lesions on the skin that can be triggered or worsened by exposure to sunlight. Occasionally, the inflammation of Sjogren’s syndrome affects the brain and nerves, as well as the kidney, liver, lungs, or esophagus.
And, though it’s rare, people with Sjogren’s syndrome are at higher risk of lymphoma, particularly non-Hodgkin lymphoma, which is a cancer of the lymph nodes. Lymphocytes are immune cells that act inappropriately in autoimmune diseases, often resulting in the overproduction of antibodies. If a particular abnormal lymphocyte begins to multiply excessively, lymphoma may develop over the course of several years.
Causes and Types of Sjogren’s Syndrome
Experts don’t know for sure what causes Sjogren’s syndrome, but some believe that it’s a combination of genetics and a bacterial or viral infection. The majority of people diagnosed with Sjogren’s syndrome are between the ages of 40 and 69. Those at risk include people who already have an autoimmune disease, such as rheumatoid arthritis or systemic lupus erythematosus, commonly known as lupus, and those who have family members with an autoimmune disease.
There are two types of Sjogren’s syndrome. Primary Sjogren’s syndrome occurs on its own and is not associated with another illness. Secondary Sjogren’s syndrome develops in a person who has another autoimmune disease, usually rheumatoid arthritis or lupus. Treatment for both types is the same.
There is no cure for Sjogren’s syndrome, but treatment can address symptoms and improve quality of life.
Diagnostic Tests for Sjogren’s Syndrome
To diagnose Sjogren’s syndrome, your doctor asks about your symptoms and medical history, as well as what medications you take. Some medications, including antidepressants and antihistamines, can cause similar symptoms of dryness.
Your doctor may use one or more of the following tests to diagnose Sjogren’s syndrome.
A blood test can detect specific antibodies—immune system proteins that normally bind to harmful substances—that may signal autoimmune diseases. The antibodies associated with Sjogren’s include anti-Ro (SS-A) and anti-La (SS-B) antibodies, rheumatoid factor, and antinuclear antibodies.
Your doctor may also use blood tests to rule out conditions with similar symptoms, including other autoimmune disorders, such as lupus, rheumatoid arthritis, sarcoidosis, and hypothyroidism, and liver disease, such as hepatitis C.
Sialometry is a noninvasive test used to measure how much saliva you produce. During this test, you are asked to sit without chewing or talking for 5 to 15 minutes, and spit the saliva that collects in your mouth into a tube for measurement. Alternatively, you may be asked to perform this test after stimulating saliva production by chewing on gauze or placing lemon juice on your tongue.
Your doctor assesses how much saliva is produced in a certain period and measures it against predetermined standards of saliva production.
Biopsy of the Inner Lip
At NYU Langone, doctors use the results of a lip biopsy to confirm Sjogren’s syndrome and rule out other diagnoses. The biopsy involves the removal of a small amount of tissue containing tiny salivary glands that’s examined under a microscope. Your rheumatologist may refer you to an ear, nose, and throat specialist for the biopsy.
The doctor first injects a local anesthetic into your lower lip. Then, using a needle or a scalpel and tweezers, the doctor removes roughly five salivary glands and sends them to a laboratory for examination. Stitches may be necessary to close the incision, and there may be soreness or numbness after the procedure.
The pathologist, a doctor who studies diseases in a laboratory, looks for evidence of inflammatory cells around the salivary glands that are indicative of Sjogren’s syndrome. It takes about one week to get biopsy results.
Your doctor may examine your eyes to see if you have dry eye syndrome, a chief symptom of Sjogren’s syndrome. Although only a small percentage of people with dry eyes have Sjogren’s syndrome, an eye exam can help a doctor make a diagnosis when it’s taken into consideration with other symptoms.
To diagnose dry eye, your rheumatologist may recommend that you see an ophthalmologist, who may perform a diagnostic test, such as Schirmer’s test or an epithelial staining test.
During Schirmer’s test, the ophthalmologist places a strip of a special paper on the inside of both lower lids. After five minutes, the doctor assesses how much moisture each eye has produced. If your eyes produce less than a certain amount, you may have dry eye syndrome.
During an epithelial staining test, your ophthalmologist administers a painless drop into each eye that stains any abnormal cells in the epithelium, the protective layer of cells on the cornea. Using a slit lamp—a low-powered microscope that shines a light beam into your eye—the doctor can examine the cells for signs of damage associated with dry eye syndrome.