Sjogren’s disease

What causes Sjögren's disease?

Sjögren's disease (also written Sjogren's disease) is an autoimmune condition. This means that instead of protecting the body from infection or illness, the immune system reacts abnormally and starts attacking healthy cells and tissue.

In Sjögren's disease, the immune system attacks the tear and saliva glands, along with other secretory glands throughout the body.

The reasons for this remain unknown, but research suggests that it is triggered by a combination of genetic, environmental and possibly hormonal factors. Some people are thought to be more vulnerable to the disease from birth, and certain events, such as an infection, can then trigger the problems with the immune system.

Healthcare professionals classify Sjögren's disease as being either:

• primary, when the disease develops by itself and not as the result of another condition
• secondary, when the disease develops in combination with another autoimmune disorder, such as lupus or rheumatoid arthritis

Causes of Sjogren's disease

It is not known exactly what causes Sjögren's disease, but it is thought to be linked to a problem with the immune system.

The immune system

Your immune system usually helps protect the body from infection and illness by making antibodies. Antibodies attack bacteria and viruses, which helps stop you from becoming ill.

An autoimmune condition causes your immune system to react abnormally. Instead of attacking foreign cells, such as bacteria, the antibodies start attacking your body's healthy cells and tissue.

In Sjögren's disease, the parts of the body usually affected are the tear, saliva and vaginal glands, which are collectively known as the exocrine glands.

The antibodies damage the exocrine glands so they can no longer function normally. There is some evidence that the immune system also damages the nerves that control these glands, which further reduces how well they work.

The immune system can go on to damage other parts of the body, such as muscles, joints, blood vessels, nerves and, less commonly, organs.

Possible triggers for Sjögren's disease

Primary Sjögren's disease

Most researchers believe that primary Sjögren's disease is triggered by a combination of genetic and environmental factors.

Certain people are born with specific genes that make them more vulnerable to a faulty immune system. Then, many years later, an environmental factor, possibly a common virus, triggers the immune system to stop working properly.

The female hormone oestrogen also seems to play a role. Sjögren's disease mostly occurs in women, and symptoms usually start around the time of the menopause, when oestrogen levels begin to fall. Falling oestrogen levels can contribute to dryness, and this dryness could make the condition more noticeable.

Secondary Sjögren's disease

Sjögren's disease can be associated with other autoimmune conditions, such as rheumatoid arthritis or lupus. This is known as secondary Sjögren's disease.

The exocrine glands

Your saliva and tear glands play a vital role in protecting your mouth and eyes, which is why the symptoms of Sjögren's disease can be widespread and troublesome.

The importance of tears

We usually only notice our tears when we cry, but our eyes are always covered by a thin layer of tears, known as a tear film.

Tears are made up of a mix of water, proteins, fats, mucus and infection-fighting cells. Tears serve several important functions. They:

• lubricate the eye
• keep the eye clean and free of dust
• protect the eye against infection
• help stabilise your vision

The importance of saliva

Saliva also serves several important functions, including:

• keeping the mouth and throat naturally lubricated
• aiding digestion by moistening food and containing enzymes that can break down certain starches
• acting as a natural disinfectant (saliva contains antibodies, enzymes and proteins that protect against some common bacterial and fungal infections)

Sjögren's disease (also written Sjogren's disease) can be hard to diagnose, because its symptoms look like those of other conditions and there is no single test for it.

Your doctor will ask about your symptoms and carry out a test to see how dry your mouth and eyes are.

Diagnosing Sjogren's disease

Sjögren's disease can be hard to diagnose because the symptoms are similar to those of other health conditions.

You may end up seeing different health professionals for your different symptoms, such as a dentist for a dry mouth, an eye specialist or optician for dry eyes and a gynaecologist for a dry vagina. This can sometimes make it harder to reach a firm diagnosis.

See your doctor if you notice any symptoms of dryness, particularly of your eyes and mouth.

Screening questions

Experts in the field have come up with a series of screening questions, which may be useful if you are worried you may have Sjögren's disease.

If you answer "yes" to most of the questions below, you may have Sjögren's disease and will probably be advised to have further tests.

• Have you had daily, persistent, troublesome dry eyes for more than three months?
• Do you keep having a feeling of grit in your eye?
• Do you need to use eye drops containing tear substitutes more than three times a day?
• Have you had a daily feeling of dry mouth for more than three months?
• Do you keep getting swollen salivary glands (located between your jaw and your ears)?
• Do you often drink liquids to help you swallow food?

Further testing

Tests used to diagnose Sjögren's disease include:

• tear break-up time and Schirmer tests
• a lip biopsy
• blood tests
• salivary flow rate

These are explained below.

Tear break-up time and Schirmer tests

Tear break-up time and Schirmer tests are usually carried out by an ophthalmologist (a doctor who specialises in treating eye conditions).

The tear break-up time test measures how well your tear glands are working. A non-toxic dye is dropped onto the surface of your eye. The colour of the dye lets the ophthalmologist see how well your tear film is functioning and how long it takes for your tears to evaporate.

This test is also carried out using a slit lamp. A slit lamp is a low-power microscope with a high-intensity light source that can be focused to shine in a narrow beam. The specialist will use the slit lamp to examine your tear glands more closely.

In the Schirmer test, small strips of blotting paper are placed inside your lower eyelid. After five minutes, the strips are removed to see how much of the paper is soaked with tears.

Lip biopsy

During a lip biopsy, a small tissue sample is removed from your inner lip and examined under a microscope. A local anaesthetic is injected into the inner surface of your lower lip to numb the area, before a small cut is made to remove a few of your minor salivary glands.

Clusters of lymphocytes (a type of white blood cell) in the tissue can point to Sjögren's disease.

Blood tests

Blood tests are carried out to look for antibodies known as anti-Ro and anti-La (or SS-A and SS-B), which are produced when the immune system has been affected by Sjögren's disease.

These antibodies are only present in about 60% of people with Sjögren's disease, so it is possible to have a negative blood test result and still have the condition.

Salivary flow rate

A salivary flow rate test measures how much saliva your glands produce.

You will usually be asked to spit as much saliva as you can into a cup over a five-minute period. The amount of saliva is then weighed or measured. An unusually low flow rate can point to Sjögren's disease.

There is no cure for Sjogren's disease, but treatment can do a lot to keep the symptoms under control.

Dry eyes and a dry mouth can usually be eased with artificial tears and artificial saliva.

It is important to look after your eyes and mouth carefully, because you are more likely to pick up an infection. Good eye and mouth care helps prevent problems such as ulcers on the cornea and tooth decay.

In severe cases, your doctor may suggest medicine or surgery.

Treating Sjogren's disease

Sjogren's disease cannot be cured, but treatment helps relieve symptoms such as dryness of the eyes and mouth.

The disease affects everyone differently, so your treatment plan will be built around your own needs.

Eye care

Artificial tears

Mild to moderate dry eye can usually be treated well with eye drops known as "artificial tears", a liquid that works like natural tears. You can buy these drops from a pharmacy without a prescription.

Many different types of eye drops are available, so you can try a few brands to find the one that suits you best. If you use eye drops often (more than three times a day), choose one that does not contain preservatives. There is evidence that too much exposure to preservatives can damage the surface of the eye.

If your eyes become irritated, your doctor may recommend a short course of eye drops containing corticosteroids. Long-term use of corticosteroids is not advised, because they can cause serious side effects.

To keep the chance of side effects as low as possible, you will be given the lowest dose that works, for the shortest time needed.

Moisture chamber spectacles

Simply wearing glasses cuts down tear evaporation by up to 30%. You can get even more benefit from specially made glasses called moisture chamber spectacles. These wrap around your eyes like goggles, holding in moisture and shielding the eyes from dust and other irritants.

Some people used to feel awkward wearing them, but modern designs look much like sports glasses.

Punctal plugs

Punctal occlusion is a widely used method in which the tear ducts (the small channels that drain tears away) are sealed with tiny plugs. This keeps more tears on the surface of the eye, so it stays better protected.

Temporary silicone plugs are usually tried first to see whether they help. If they do, longer-lasting plugs can be fitted.

Mouth care

Looking after your mouth

Several simple steps can help keep your mouth moist, including:

• keeping up good oral hygiene to prevent tooth decay and gum disease
• drinking more fluids
• chewing sugar-free gum to encourage saliva production
• sucking ice cubes to moisten the mouth and ease dryness
• using mouth rinses regularly to soothe the mouth and guard against infection

If you smoke, try to stop. Smoking irritates the mouth and makes saliva dry up faster.

Read more about how to stop smoking

Saliva substitutes

Various saliva substitute products can help keep your mouth moist. But they cannot do the job that natural saliva does in preventing infection, so you will still need to take very good care of your teeth and gums.

Saliva substitutes come as a spray, lozenge (a medicated sweet), gel or gum. Your doctor or pharmacist can advise which product would suit you best.

Medication for Sjogren's disease

Pilocarpine

Pilocarpine is a medicine often used to treat dry eyes and dry mouth. It works by stimulating the glands to produce more saliva and tears.

Side effects of pilocarpine include:

• hyperhidrosis (sweating much more than usual)
• nausea
• diarrhoea
• heartburn
• pain in the abdomen (stomach area)
• needing to pass urine more often

For some people these side effects are mild. Others find they outweigh the benefits.

Do not take pilocarpine if you have asthma or chronic obstructive pulmonary disease (COPD), or if you are pregnant or breastfeeding.

Hydroxychloroquine

Hydroxychloroquine has been shown to slow the immune system's attack on the tear and saliva glands. It can also help ease related muscle pain, joint pain and stiffness.

You will need to take hydroxychloroquine for several weeks before you notice any improvement, and it may take up to six months to feel the full benefit.

Side effects are uncommon and usually mild. They include:

• nausea
• skin rash
• loss of appetite
• stomach cramps
• vomiting

In very rare cases, hydroxychloroquine can damage the retina and affect vision. You will probably be asked to have an eye examination so your retina can be checked before you start treatment. Regular eye checks (usually at least once a year) are also recommended once you are on the medicine.

Women who are breastfeeding should not use hydroxychloroquine.

Sjogren's disease (also written Sjögren's disease) can sometimes lead to complications. For example, your eyesight could be permanently damaged if the reduced tear production is not treated.

Sjogren's disease also raises your risk of developing non-Hodgkin lymphoma, which is a cancer of the lymph glands. The chances are still low, at around 5%.

Women with Sjogren's disease have a higher chance of having a baby with a temporary "lupus" rash or heart problems. Any pregnancy will be closely monitored for possible problems.

Who is affected by Sjogren's disease?

Sjogren's disease most commonly affects people aged 40 to 60, and women make up about 90% of cases.

It is hard to know exactly how many people have the disease, because many people do not see a doctor about their symptoms.

Complications of Sjogren's disease

Sjogren's disease is not usually life-threatening, but it is linked to some more serious problems.

Non-Hodgkin lymphoma

It is estimated that people with Sjogren's disease are 44 times more likely to develop non-Hodgkin lymphoma than people who do not have the condition.

Non-Hodgkin lymphoma is a cancer of the lymphatic system. The lymphatic system is a network of vessels and glands (lymph nodes) spread throughout your body, much like your blood vessels.

This increased risk may sound alarming, but the chance of a person with Sjogren's disease developing non-Hodgkin lymphoma is still small. It affects only around 5% of people with the disease.

Even so, if you have Sjogren's disease, it helps to know the main early sign of non-Hodgkin lymphoma: a painless swelling in a lymph node (gland), usually in the neck, armpit or groin. Tell your doctor about any swollen lymph nodes.

Eye damage

If dry eyes are not treated, they can become inflamed, and ulcers can form on the surface of the eye (corneal ulcers).

If corneal ulcers are left untreated, they can lead to loss of vision and permanent damage to your sight.

Pregnancy

If you have Sjogren's disease and are planning to become pregnant, ask your doctor to test you for certain antibodies. These antibodies may be present in Sjogren's disease and are known to cause a temporary lupus rash in newborn babies. In very rare cases, they can also cause heart defects in babies.

If these antibodies are found, there is usually no reason why you cannot continue with the pregnancy, but your child may need extra specialist care during the pregnancy and after the birth.

Other conditions

A number of other conditions have been linked to Sjogren's disease, including:

• peripheral neuropathy, a condition that often involves loss of feeling in the hands and feet
• Raynaud's phenomenon, where blood flow to the hands is restricted, which can make them feel cold, numb and painful
• kidney problems, such as inflammation or kidney stones
• an underactive thyroid gland (hypothyroidism), which can lead to tiredness and weight gain
• irritable bowel syndrome (IBS), which can cause stomach pain and irregular bowel movements
• tooth cavities