Sjögren’s syndrome

In some patients, the disease can also lead to inflammation of other organs, e.g. the lungs, joints or nervous system. A dreaded complication is the transition to lymphoma (lymph gland cancer). There is no cure for Sjögren’s syndrome. The therapy depends on the extent of the infestation: if only the glands are affected (dry eyes and mouth), symptomatic treatment is generally used, e.g. with saliva or tear substitutes. In the case of systemic infestation, medication is used which influences the immune system.

Overview: What is Sjögren's syndrome?

Dry eyes feel rough and uncomfortable. They cause you to constantly rub your eyes. There are many causes for this – but anyone who also suffers from dry mouth and observes these symptoms over a long period of time could be suffering from Sjögren’s syndrome.

This autoimmune disease was named after the Swedish ophthalmologist Henrik Sjögren, who first described this disease in his dissertation in 1933. In Sjögren’s syndrome, the body’s own immune system attacks the tear and salivary gland tissue. This leads to inflammation and thus to a reduced production of tear fluid and saliva. The disease is often accompanied by pronounced fatigue and joint pain. Sjögren’s syndrome is one of the collagenoses (autoimmune connective tissue diseases). The name “syndrome” refers to a disease with several different symptoms. Sometimes the disease is called “sicca syndrome” after the Latin word “siccus” (dry). However, the disease itself can go far beyond the dryness symptom and also affect other organ systems.

Sjögren’s syndrome: frequency and age

Sjögren’s syndrome affects women significantly more often than men, with an average of nine out of ten sufferers being women. Overall, however, this disease is rare: Only around 0.03 to 0.1 percent of the population suffers from it, in Switzerland around 8,000 people according to estimates. In many cases, Sjögren’s syndrome occurs as a concomitant symptom of another disease (e.g. rheumatoid arthritis or lupus erythematosus). Sjögren’s syndrome is usually diagnosed in middle age. However, very young and very old people can also fall ill.

Sjögren's syndrome: causes and risk factors

As with many autoimmune diseases, there is no known direct cause for this dysregulation of the body’s own defenses in Sjögren’s syndrome. However, the disease occurs more frequently in some families – apparently a tendency to Sjögren’s syndrome can be inherited. A connection with hormones, environmental factors and previous viral infections is also being discussed among experts. As the symptoms are relatively unspecific, it often takes a long time before the disease is diagnosed with certainty.

If it is present as an independent disease, it is referred to as primary Sjögren’s syndrome. If the symptoms are the result of another, leading underlying disease, experts speak of secondary Sjögren’s syndrome. These can include the following diseases:

• Systemic lupus erythematosus (SLE)
• Rheumatoid arthritis
• Systemic sclerosis
• Myositis (e.g. polymyositis, dermatomyositis, anti-synthetase syndrome)
• Mixed collagenosis

Furthermore, other autoimmune diseases (e.g. of the thyroid, pancreas or liver) can also lead to secondary Sjögren’s syndrome.

Symptoms: Sjögren's syndrome causes glandular symptoms with the main symptom of dryness

Dryness of the eyes and mouth is the most common symptom of Sjögren’s syndrome. Sufferers have the feeling of having a foreign body in their eye. If left untreated, this can lead to increased inflammation of the eyes and damage to the cornea.

Due to the reduced saliva flow, many sufferers develop dental problems. Their risk of tooth decay or early tooth loss is twice as high as that of healthy people. The risk of a fungal infection on the oral mucosa is even ten times higher. However, older people suffer relatively frequently from dry eyes and dry mouth, partly due to various medications such as antihypertensives or antidepressants. Therefore, only a doctor can decide whether Sjögren’s syndrome is actually present after a thorough examination.

The following organs can also be affected by dryness:

• Genitals: Some women complain of dry genitals, which can lead to pain during sexual intercourse.
• Nose: If the mucous membranes of the nose are not sufficiently moistened, they can only perform their defense function to a limited extent.
• Respiratory tract: The trachea, lungs and bronchial system also suffer from the dryness caused by the disease, which can manifest itself in a dry cough.
• Skin: Dry skin can lead to itching.

Extraglandular (=outside the glands) symptoms of Sjögren’s syndrome

In addition to the noticeable dryness of the mucous membranes, there are other symptoms that are often very distressing for sufferers. These are referred to as extraglandular (= outside the glands) symptoms. While non-specific problems such as pronounced tiredness (known as fatigue) and diffuse soft tissue pain (similar to fibromyalgic syndrome) are relatively common, the disease can also directly affect other organ systems and cause corresponding symptoms, for example:

• Joint inflammation with swelling of the joints and morning stiffness
• Muscle inflammation with muscle weakness
• Nerve inflammation (e.g. polyneuropathy) with nerve loss/pain
• Pneumonia and even scarring of the lungs (pulmonary fibrosis)
• Vascular inflammation
• Skin inflammations
• Myocarditis
• Kidney infestation
• Raynaud’s syndrome, a white/blue/red discoloration of the fingers and toes due to cold or stress

A dreaded complication is the development of lymphoma. The risk is 15 to 20 times higher in Sjögren’s syndrome patients who have positive anti-SSA/SSB antibodies in their blood compared to the normal population.

Sjögren’s syndrome: diagnosis at the USZ

The diagnosis of Sjögren’s syndrome cannot be made on the basis of a single finding or laboratory value alone, but only on the basis of an overall view of all findings and the clinical presentation. This is why the assessment by specialized doctors is important.

The first step is to measure the dryness. The production of tear fluid can be assessed using the so-called Schirmer test. To do this, two special strips of paper are placed in the eyelids and after five minutes the amount of tear fluid with which they have moistened the paper strips is assessed. Oral saliva can also be measured.

An ultrasound examination of the major salivary glands can detect typical changes in the glandular tissue. Other imaging procedures such as MRI or CT can also be used. In selected cases, a biopsy of the salivary glands is useful. After local anesthesia, a small incision (usually less than one centimeter) is made on the inside of the lower lip with a scalpel and then several salivary glands about the size of a pinhead are removed. After special staining, the inflammation typical of Sjögren’s syndrome can then be detected in the tissue under the microscope.

Laboratory diagnostics for Sjögren’s syndrome

Laboratory values are also important for diagnosis. An important indication of Sjögren’s syndrome is the detection of antinuclear antibodies (ANA) as well as anti-SSA/SSB antibodies and rheumatoid factors in the blood. The antibodies can be found in the blood years before the onset of further symptoms. However, there are also patients without these typical antibodies. Furthermore, various additional laboratory values can be determined, such as the complement factors C3 and C4 as well as cryoglobulins, especially those that can better assess the risk of developing lymphoma.

Sjögren's syndrome: prevention, early detection, prognosis

The diagnosis of Sjögren’s syndrome should be made by specialist physicians and regular check-ups are important, especially for the early detection of possible lymphoma or organ involvement that requires therapy adjustment.

Course and prognosis of Sjögren’s syndrome

With good treatment of Sjögren’s syndrome, the life expectancy of those affected hardly decreases. If Sjögren’s syndrome occurs as a concomitant symptom of another disease, the prognosis usually depends on the underlying disease. If a complication of lymphoma occurs, the prognosis depends on the stage and type of lymphoma.

Pregnant women who suffer from Sjögren’s syndrome and have detectable anti-SSA/SSB antibodies in their blood have an increased risk of cardiac arrhythmia in the fetus (so-called congenital heart block). This in turn can lead to the death of the unborn child. For this reason, close monitoring of the fetal heart rhythm between the 16th and 31st week of pregnancy is necessary in patients with the disease. The risk can be significantly reduced if the drug hydroxychloroquine is started before the planned pregnancy.

Self-help groups

Sjögren's syndrome: treatment of glandular symptoms

According to current knowledge, a direct cure for Sjögren’s syndrome is not possible. The treatment of sicca symptoms (dryness symptoms) is mostly symptomatic.