What is it?
Sjögren’s syndrome is an autoimmune disorder that can affect a wide range of organs in the body. It particularly affects secretion production at the mucous membranes, causing dry mouth, decreased tear production, and dryness of other body membranes. Dry eyes and dry mouth is often referred to as 'sicca syndrome' and Sjögren's is a very important cause.
Symptoms of Sjögren's may include;
- dry and gritty eyes
- dry mouth with difficulty chewing and swallowing
- decreased sense of taste and smell
- swollen salivary glands, especially the parotid
- dryness of the vagina, painful intercourse
- swollen lymph nodes
- joint pains
- fatigue
More rarely the following may also occur
- Raynaud’s (20%)
- Kidney involvement
- Neuropathy, causing numbness or tingling in hands or feet
- Vasculitis, which can cause rashes especially on the legs
Sjögren’s syndrome is much more common in women than men (9:1), and usually occurs between 40-60 years. It is estimated that 0.5-3% of the adult population may be affected. In the UK, 500,000 people may be affected.
In Sjögren’s syndrome, the body’s immune system mistakenly reacts to the tissue in glands that produce secretions such as the salivary and tear glands. These glands typically have immune cells known as lymphcytes inside them which results in damage. The presence of particular autoantibodies in the blood is used to help diagnosis.
Sjögren’s syndrome can occur alone (primary Sjögren’s syndrome) or from another well-defined autoimmune diseases such as rheumatoid arthritis (RA), progressive systemic sclerosis (PSS), polymyositis (PM), and Systemic Lupus Erythematosus (SLE).
There is an increased likelihood of lymphoma among patients with primary Sjogren’s syndrome.
Tests for Sjögren’s syndrome may include:
- Positive Schirmer’s test. In this test, a piece of filter paper is hooked over the lower eyelid and left there for 5 minutes. It is used to assess dryness of the eyes, though is not specific for Sjogren’s. Rose Bengal staining of the eyes can be used to look for scarring affecting the conjunctiva and cornea.
- Antinuclear antibodies (ANA) (positive in most cases)
- Rheumatoid factor (RF) (often positive)
- Antibodies specific to Sjögren’s syndrome (SS): anti-SS-A and SS-B; SS-A is also called Ro, while SS-B is also called La. These tests form part of the ENA (extractable nuclear antigen) panel. In some laboratories subsets of Ro antibodies (Ro52 and Ro60) only may be tested. In general Ro60 has a much stronger association with primary Sjogren’s, but increasingly Ro52 is being recognised in secondary Sjogren’s and may also be a marker for a subset of patients with systemic sclerosis.
- Salivary gland antibodies
- Full blood count - may show reductions in cell counts, especially white blood cells
- ESR - often raised
Other tests:
- In uncertain cases, salivary gland biopsy can be performed
There is no cure, and treatment is based on the symptoms. Dry eyes are treated with artificial tears, a tear stimulant, or eye lubricant. Dry mouth may be helped by frequent small drinks of water or sugarless chewing gum to stimulate saliva production. Regular dental care is critical as the oral dryness predisposes to decay.
Arthritis symptoms are treated with simple painkillers, or, non-steroidal anti-inflammatory medicines, such as ibuprofen and diclofenac. Corticosteroids and immunosuppressive medications are reserved for more severe cases.