Symptoms and Complications
- Fatigue (79%)
- Dry eyes (75%)
- Dry mouth (73%)
- Joint pain (65%)
- Trouble sleeping (64%)
- Increased rate of neonatal lupus erythematosus with congenital heart block requiring a pacemaker in pregnant women with anti-Ro/SS-A and anti-La/SS-B antibodies
- Type I cryoglobulinemia
- Affection of organs such as the liver, pancreas, kidneys, lungs, and central nervous system
Associated Conditions
- Celiac disease
- Fibromyalgia
- Systemic lupus erythematosus (lupus)
- Autoimmune thyroiditis
- Multiple sclerosis and spondyloarthropathy
- Several malignancies, principally non-Hodgkin lymphoma
Causes and Pathogenesis
- Combination of genetics and an environmental trigger such as exposure to a virus or bacterium
- Can occur independently (primary Sjögren's syndrome) or as a result of another connective tissue disorder (secondary Sjögren's syndrome)
- Association with other autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), or systemic sclerosis
- Lack of fully elucidated pathogenetic mechanisms
- Immune system-mediated loss of exocrine glands
- Infiltration of lymphocytes causing glandular dysfunction
- Association with increased levels of IL-1RA in cerebrospinal fluid (CSF)
- Interleukin 1 system involvement and cytokine-induced sickness behavior
Genetic Predisposition and Environmental Triggers
- The major histocompatibility complex/human leukocyte antigen (MHC/HLA) region is significantly associated with primary Sjögren's syndrome.
- A genome-wide association study identified six independent loci associated with primary Sjögren's syndrome.
- These loci include IRF5, STAT4, BLK, IL12A, TNIP1, and CXCR5.
- HLA-DR and HLA-DQ alleles are involved in the pathogenesis of Sjögren's syndrome.
- HLA class II alleles are associated with specific subsets of autoantibodies.
- Glandular viral infection can activate the innate immune system through toll-like receptors.
- Epstein-Barr virus (EBV), human T-lymphotropic virus 1, and hepatitis C virus have been implicated in Sjögren's syndrome.
- EBV reactivation is common in Sjögren's patients, indicating viral replication and immune response in target organs.
- The exact mechanisms of EBV reactivation in Sjögren's lesions are not fully understood.
- Other environmental factors may also contribute to the development of Sjögren's syndrome.
Autoantibodies and Epigenetic Abnormalities
- Loss of B-cell tolerance leads to the production of autoantibodies.
- Anti-SSA/Ro and anti-SSB/La antibodies are associated with Sjögren's syndrome.
- Seropositivity for anti-Ro and anti-La antibodies is linked to greater disease severity and longer duration.
- These antibodies are abundant in the salivary glands of Sjögren's patients.
- Their role in the pathogenesis of Sjögren's syndrome is essential.
- Epigenetic abnormalities may play a key role in the pathogenesis of autoimmune diseases, including Sjögren's syndrome.
- DNA methylation, histone acetylation, and microRNA expression are potential epigenetic mechanisms involved.
- Research in this area is limited.
- Further studies are needed to understand the impact of epigenetic abnormalities on Sjögren's syndrome.
- Targeting epigenetic modifications could be a potential therapeutic approach.
Ethnic Variations
- Patients of different ethnic origins carry different HLA-susceptibility alleles.
- HLA-DR and HLA-DQ alleles are involved in Sjögren's syndrome pathogenesis.
- Northern and Western European and North American patients have a high prevalence of B8, DRw52, and DR3 genes.
- HLA class II alleles are associated with specific subsets of autoantibodies.
- Ethnic variations may contribute to differences in disease presentation and severity.
Sjögren syndrome or Sjögren's syndrome (SjS, SS) is a long-term autoimmune disease that affects the body's moisture-producing glands (lacrimal and salivary), and often seriously affects other organ systems, such as the lungs, kidneys, and nervous system.
Sjögren's syndrome | |
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Other names | Sjögren's syndrome, sicca syndrome |
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Image with a microscope of focal lymphoid infiltration in the minor salivary gland associated with Sjögren's syndrome. | |
Pronunciation |
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Specialty | Immunology, rheumatology ![]() |
Symptoms | Dry mouth, dry eyes, other areas of dryness |
Complications | Lymphoma |
Usual onset | Middle age |
Duration | Long term |
Causes | Autoimmune disease (unknown cause) |
Diagnostic method | Tissue biopsy, blood tests |
Differential diagnosis | Medication side effect, anxiety, sarcoidosis, amyloidosis |
Treatment | Artificial tears, medications to reduce inflammation, surgery |
Prognosis | Normal life expectancy |
Frequency | ~0.7% |