SJOGREN'S SYNDROME
What is Sjogren's Syndrome?
In 1933. a Swedish physician, Henrik Sjogren, drew attention to the large
number of his female patients whose chronic arthritis was accompanied by dry
eyes and dry mouth.
Since then patients with this combination of symptoms have been described as
having Sjogren's Syndrome. Today it is recognised to be the second most common
auto-immune rheumatic disease. Recent estimates suggest that there may be as
many as half a million sufferers in the UK alone.
There are two categories of Sjogren's Syndrome (SS). It can be localised,
affecting mainly the eyes and/or the mouth. Or. it can be systemic, and
occurring in conjunction with connective tissue diseases such as Rheumatoid
arthritis, lupus or scleroderma.
The symptoms of Sjogren's Syndrome:
The dry eyes result in feelings of irritation, grittiness and, sometimes,
burning. The eyelids may stick together and the patients may not be able to
tolerate strong sunlight. The dry mouth results in a burning sensation in the
mouth or throat; the voice may be hoarse or weak; food can be difficult to
swallow because it sticks to the tissues; the salivary glands may become
enlarged and painful. Patients frequently experience a "hurt all
over" sensation, as if they have been battered, and feel continually
exhausted.
What is the cause?
SS is a chronic auto-immune disease in which the body's immune system
reacts against itself, destroying the exocrine (mucous-secreting) glands as
though they were foreign bodies. Autoimmunity means making antibodies to your
own tissues. Antibodies are normally made to counter infectious agents, called
antigens, and are designed to destroy them. When antibody and antigen meet,
inflammation results. When this happens, as for example, in influenza, the
worst symptoms occur when the antibodies are actually fighting the antigen, in
this case their 'flu virus; but when the virus is removed the symptoms vanish.
In auto-immune diseases it is impossible to get rid of the antigen because it
is part of the body.
In SS, and so long as the antibody is produced, inflammation continues.
Patients frequently describe their own symptoms as being those of permanent
influenza. The inflammation in SS is mainly in the salivary and lachrymal
glands, though it can spread to joints and blood vessels in the skin where it
may cause rashes. In rare cases it can affect the liver and kidneys.
How is it diagnosed?
A number of tests are available for diagnosing SS. They include:
examination of the eyes by rose-bengal staining and measurement of tear
production (Schirmer test); measurement of saliva production; x-ray examination
of certain salivary glands (sialography); blood tests to determine the presence
of antibodies to two identifiable antigens (Ro and La); and a lip gland biopsy.
Can it be treated?
The symptoms of SS can be treated depending on the degree of their
severity. However, no treatment has yet been found to restore glandular
secretions. Artificial tears help to lubricate dry eyes, and some sufferers
benefit from using lacriserts; in severe cases punctal occlusion is employed to
retain moisture in the eye. Artificial salivas may provide temporary relief for
the dry mouth, and fluoride gels and remineralising solutions are prescribed to
restore the proper chemical balance in the mouth. Anti- inflammatory drugs may
reduce the swelling of enlarged and inflamed glands. In certain cases, systemic
medications, such as corticosteroids or piaquenil, are employed, and in
complicated SS, immuno-suppressive drugs are sometimes found to be necessary.
What hope for a cure?
Far more is known about the genetics and antibodies in SS than in many
other rheumatic diseases and there is hope that the external agent (possibly a
virus), which induces auto-immunity in an individual already predisposed by
genetic or hormonal factors to the disease, may eventually be identified.
Research into SS is being conducted in the USA and in several centres in
Europe, including England.
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