There are many different types of autoimmune diseases yet Sjogren’s syndrome which is among the more common of these conditions is not very well known. It is a condition marked by dry eyes and a dry mouth but there is much to this disease that can extend to almost every part of the body. There is no cure for Sjogren’s syndrome although many drugs can limit the disease and control the symptoms quite effectively.
What is Sjogren Syndrome?
Sjogren syndrome is a chronic disorder marked by inflammation of the exocrine glands (glands with ducts) which produce secretions to moisturize tissue. It mainly affects the tear glands and salivary glands thereby leading to a deficiency of tears and saliva respectively. However, other organs and systems may also be affected. For example, dry skin is commonly reported and the joints, blood vessels, muscles and lungs may also be affected among other tissues and organs.
As with most autoimmue diseases, the reason for the inflammation in these different tissues and organs is due to the immune system. However, the exact cause is not clearly understood. Sometimes Sjogren’s syndrome may occur along with other autoimmune diseases like rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Although Sjogren’s syndrome is not as popularly known as RA and SLE, it is actually the second most common rheumatologic condition after SLE.
Causes of Sjogren Syndrome
The immune system’s primary function is to protect the body against foreign threats. One of the ways it does this is to isolate invaders and attack it through a host of mechanisms including the action of immune chemicals and immune cells. Sometimes the system is disrupted and the immune mechanisms turn against the body itself. It may target specific tissues or just about any organ in the body thereby triggering inflammation. This is known as an autoimmune disease.
In Sjogren’s syndrome the tissues of certain glands are targeted. These glands are known as exocrine glands because it releases its secretions through a duct. More specifically it is the glands responsible for moisturizing tissues that is affected. The tear glands and salivary glands are the main targets. The reason why the immune system is triggered to behave in this manner is not clearly understood. However, there may be certain triggers such as viral or bacterial infections.
It is important to note that these viruses or bacteria do not cause Sjogren’s syndrome since it is not an infectious disorder. However, the immune system’s response to these viruses and bacteria may then direct the immune cells towards the body’s own tissue afterwards. Certain genes may predispose a person to developing Sjogren’s syndrome but this as well is not a cause of the disease. Rather it increases the chance of developing Sjogren’s syndrome.
Some people have been identified as being more likely to develop Sjogren’s syndrome based on risk factors.
- Women who are about 9 times more likely than men to develop Sjogren’s syndrome.
- People who are older than 40 years of age.
- A history of other rheumatic diseases like rheumatoid arthritis and SLE.
Irrespective of these risk factors, Sjogren’s syndrome could still affect a person who is deemed low risk.
Primary and Secondary
Sjogren’s syndrome can be classified as primary or secondary.
- Primary Sjogren’s syndrome occurs on its own without any other autoimmune condition at the time. However, it is possible that other conditions can arise in the future.
- Secondary Sjogren’s syndrome occurs in the presence of other rheumatologic conditions such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).
Signs and Symptoms
The main symptoms of Sjogren’s syndrome are:
- Dry mouth
- Dry eyes
- Swollen parotid gland
These are often the first symptoms as well. The term sicca is used to refer to the dryness characteristic of Sjogren’s syndrome. Therefore it is also sometimes referred to as sicca syndrome. About half of all Sjogren’s syndrome patients also report skin symptoms, the most common being excessively dry skin. There may also be other skin symptoms like red to purple spots (purpura – bleeding under the skin) and hives (urticaria).
Apart from the skin symptoms, there may also be other symptoms affecting other parts of the body besides the glands. These extraglandular features include:
- Joint pain (arthralgia) and joint inflammation (arthritis).
- Muscle pains (myalgia).
- Paleness and even bluish discoloration of the fingers and toes (Raynaud phenomenon).
- Blood abnormalities like anemia (low hemoglobin) and leukopenia (low white cell count).
- Various airway and lung symptoms due to pulmonary diseases.
- Digestive symptoms as a result of gastrointestinal diseases.
- Neurologic abnormalities due to nerve diseases (neuropathy).
- Kidney diseases like renal tubular acidosis.
- Swollen lymph nodes (lymphadenopathy).
- Inflammation of the blood vessels (vasculitis).
- Other symptoms due to thyroid disease or liver disease.
There is a significant degree of overlap of symptoms with Sjogren’s syndrome and other rheumatologic conditions.
Tests for Diagnosis
It is not uncommon for Sjogren’s syndrome to be misdiagnosed for long periods of time. Sometimes the symptoms are incorrectly reported which can be misleading for health care professionals, like instead of complaining about dry mouth some patients may instead report increased thirst. The condition can be difficult to diagnose and may require investigations that are not routinely done. A range of tests may be conducted such as:
- Blood tests to identify inflammation, levels of blood cells and specific antibodies for rheumatologic conditions.
- Imaging studies to visualize the salivary glands:
– Sialogram where a dye is injected into the salivary glands to assess saliva flow.
– Salivary scintigraphy where a radioactive isotope is injected into the bloodstream and traced to the salivary glands.
- Biopsy where a small sample of salivary gland tissue is collected and examined under a microscope to identify cellular changes that may be indicative of Sjogren’s syndrome.
Treatment for Sjogren’s Syndrome
Medication is usually prescribed to treat and manage Sjogren’s syndrome. However, in some cases surgery may be necessary to treat the complications of the disease. Sjogren’s syndrome is a chronic disease and there is no cure for the condition. Treatment focuses on ongoing management with the use of different medication. These drugs may include:
- Medication to suppress and regulate the immune system like corticosteroids and methotrexate.
- Artificial tears to lubricate the eyes when necessary.
- Drugs to stimulate saliva and tear production like pilocarpine or cevimeline.
- Non-steroidal anti-inflammatory drugs (NSAIDs) to treat arthritis in Sjogren’s syndrome.
- Antimalarial drugs like hydroxychloroquine for arthritis that does not respond to NSAIDs.
Surgery is rarely done. It may include procedures to block the drainage of tears through ducts. Sjogren syndrome patients may also require more frequent and extensive dental work as the mouth dryness leads to a host of dental complications.