Unknown: Sjögren Syndrome

Definition
Description
Demographics
Causes and Symptoms
Diagnosis
Treatment
Prognosis
Prevention
The Future
For more information

Definition

Sjögren (pronounced SHOW-gren) syndrome, or SS, is an autoimmune disorder that primarily affects the body's tear glands and salivary glands. It is named for Henrik Samuel Sjögren (1899ndash;1986), the Swedish ophthalmologist (eye specialist) who described it in 1933. The disorder is also known as Gougerot disease or Gougerot-Sjögren syndrome, after Henri Gougerot (1881–1955), a French doctor who presented a case study of the disease in a French medical journal in 1925.

Description

Sjögren syndrome is a disorder in which the body's immune system attacks the glands that produce saliva, tears, and (in women) vaginal fluid. It can also cause dryness in such other body tissues and organs as the kidneys, digestive tract, blood vessels, lung, liver, pancreas, and the central nervous system. Most patients also experience fatigue and pains in the joints.

Doctors classify cases of Sjögren syndrome as either primary, meaning that the disorder occurs by itself; or secondary, which means that the patient has another connective tissue disorder. About half of all cases of SS are primary and the other half are secondary. The four most common diseases affecting patients with secondary Sjögren syndrome are rheumatoid arthritis, lupus, scleroderma, and polymyositis (inflammation of the muscles).

Demographics

SS is thought to affect between 0.1 percent and 3 percent of the population in all countries. According to the American College of Rheumatology (ACR), between 400,000 and 3.1 million adults in the United States suffer from the disorder. Members of all races appear to be equally affected. SS is primarily a disorder of women, however; females get SS

nine times as frequently as males. It is unusual for adolescents or young adults to develop Sjögren syndrome; the average age of patients at onset is the late forties.

Causes and Symptoms

The cause of Sjögren syndrome is not completely understood, but it is thought to be a combination of genetic factors, hormones, and environmental triggers, possibly infections. There is more than one gene that appears to be involved, but the connections between these genes and the onset of the disorder are not yet clear. Some researchers think that SS is triggered when people who are genetically susceptible are infected by a virus that has not yet been identified, and that the resultant infection causes the person's immune system to turn against the glands that produce tears and saliva. These glands include the tear glands near the eyes and the parotid glands below and in front of the ears.

The most noticeable symptoms of Sjögren syndrome are xerostomia, or dry mouth, and dry eyes. Patients with xerostomia may feel like their mouth is full of cotton or that they cannot easily talk or swallow. They are at increased risk of tooth decay because normal levels of saliva in the mouth help to protect against mouth infections and tooth decay. Patients with dry eyes may have a burning sensation in the eyes, blurred vision, or a gritty feeling beneath the eyelid. Drying of the eyes increases the risk of

Eye infections and damage to the cornea, the clear front part of the eye where light enters.

Other symptoms that patients may have include:

• Pain and stiffness in the joints and muscles
• Dry, itchy skin
• Rashes on the skin of the arms and legs
• Tingling sensations or numbness in the arms and legs
• Dryness in the vagina (in women)
• Chronic dry cough
• Fatigue or tiredness that is severe enough to interfere with daily life
• Enlargement of the parotid glands

Diagnosis

The diagnosis of Sjögren syndrome is a long and complex process that may take years because the symptoms of the disorder are not specific to it; dry eyes and mouth, for example, can be caused by certain medications, by radiation therapy, or by anxiety disorders as well as by SS. Dry eyes can also be caused by disorders or factors other than SS. The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) found that patients who were eventually diagnosed with Sjögren syndrome received the diagnosis from primary care doctors, allergists, dentists, and cancer specialists as well as from rheumatologists, who are doctors who specialize in disorders of the muscles, joints, and connective tissue. Many rheumatologists think that the diagnosis of SS is often missed.

The diagnosis is usually based on a combination of the patient's symptom history and the results of laboratory tests and imaging studies. In taking the history, the doctor will ask about medications the patient may be taking and the amount of fluid that she or he drinks in an average day. In addition, the doctor will examine the patient's mouth for evidence of an abnormally low production of saliva. In many cases of SS, the patient's tongue will be dry enough to stick to the doctor's tongue depressor. Specific laboratory tests and imaging studies may include:

• Blood tests. These are done to check the blood cell count and also look for the presence of autoantibodies, which are proteins formed when to body's immune system attacks its own tissues.
• Schirmer tear test. This is a test in which the doctor measures the amount of tears produced by the patient's tear glands by placing a

• small piece of filter paper underneath the lower eyelid for five minutes and then measuring its wetness with a ruler.
• Another eye test that may be performed involves staining the surface of the patient's eye with a dye called rose bengal. The dye will cling to areas of the cornea that have become dried out from SS. The doctor can then examine the patient's eyes through a slit lamp to determine how much the eye has been damaged by dryness.
• Sialogram. A sialogram is a special type of imaging study in which a radioactive dye is injected into the patient's parotid glands. The movement of the dye will help the doctor measure the flow of saliva from the gland into the patient's mouth.
• Lip biopsy. The doctor may take a small sample of lip tissue to check for the presence of inflammatory cells associated with SS.
• Urine test. A urine sample may be analyzed to see whether the patient's kidneys have been affected by SS.

Treatment

There is no cure for Sjögren syndrome. Treatment for the disorder is aimed at relieving symptoms. Dry eyes can be treated by the application of artificial tears in the daytime and lubricating gels or ointments at night. The gels should not be used in the daytime because they can cause blurring of vision. Another drug that can be used is called Lacriserts. It comes in the form of small tablets that the patient places in the lower eyelid. When artificial tears are added, the Lacriserts tablet dissolves and forms a film over the patient's tears that traps moisture.

Patients with dry mouth can be given either Salagen or Evoxac. These are prescription medications that stimulate glands in the mouth to produce more saliva. Patients with SS must see their dentist on a regular basis to prevent tooth decay and eventual loss of teeth. In some cases the dentist may recommend fluoride treatment to provide additional protection for the teeth. Many patients find that taking small frequent sips of water or sugar-free lemon drops helps to relieve dryness in the mouth.

Patients with muscle or joint pains caused by Sjögren syndrome can take nonsteroidal anti-inflammatory drugs, or NSAIDs. These drugs include aspirin as well as such pain relievers as ibuprofen and naproxen, and are usually available over the counter. Steroid medications can also be given to patients with SS, but the long-term use of these drugs can cause serious side effects.

Prognosis

The prognosis of patients with Sjögren syndrome is generally good. About 5 percent of patients with SS eventually develop lymphoma, or cancer of the lymph nodes. Some patients also develop inflammatory disorders of the lungs, kidneys, or liver. The majority of patients, however, are able to manage the symptoms of the disease quite well and have a normal life expectancy. The most common complications of SS for the majority of patients are an increased risk of dental cavities and eye infections.

Prevention

There is no known way to prevent Sjögren syndrome because the causes of the disorder are not yet completely understood.

WORDS TO KNOW

Cornea: The transparent front part of the eye where light enters the eye.

Lymphoma: A type of cancer that affects the lymphatic system.

Parotid glands: Glands that produce saliva, located on each side of the face below and in front of the ear.

Polymyositis: Inflammation of the muscles that causes weakness and difficulty in moving or swallowing.

Rheumatologist: A doctor who diagnoses and treats diseases of the muscles, joints, and connective tissue.

Scleroderma: A disorder of connective tissue characterized by thickening and tightening of the skin as well as damage to internal organs.

Slit lamp: An instrument that focuses light into a thin slit. It is used by eye doctors to examine eyes for a wide variety of disorders.

Xerostomia: The medical term for dry mouth.

The Future

Sjögren syndrome is not likely to become more common in the general population because it is not inherited and is not contagious. Research in the early 2000s is focused on searching for the cause of the disorder, improving the speed and accuracy of diagnosis, and looking for potential cures.

SEE ALSO Lupus; Lymphoma; Rheumatoid arthritis; Tooth decay

For more information

BOOKS

Carsons, Steven, and Elaine K. Harris, eds. The New Sjögren's Syndrome Handbook. New York: Oxford University Press, 1998. This book was written for patients diagnosed with the disorder and their families.

National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Questions & Answers about Sjögren's Syndrome, revised edition. Bethesda, MD: NIAMS, 2006. This is a 40-page booklet about Sjögren's syndrome for general readers.

WEB SITES

American College of Rheumatology (ACR). Patient Education: Sjögren's Syndrome. Available online at http://www.rheumatology.org/public/factsheets/sjogrens.asp?aud=pat (accessed May 23, 2008).

Mayo Clinic. Sjögren's Syndrome. Available online at http://www.mayoclinic.com/health/sjogrens-syndrome/DS00147 (accessed May 22, 2008).

Sjögren's Syndrome Foundation (SSF). What Is Sjögren's Syndrome? Available online in PDF format at http://www.sjogrens.org/images/SSF%20patient%20brochure.pdf (accessed May 22, 2008).