26th January 2024

Background

Sjogren’s syndrome is a chronic autoimmune inflammatory disorder characterised by dryness of the eyes and mouth, fatigue and musculoskeletal pain that is the result of diminished lacrimal and salivary gland function. 

Epidemiology 

The overall incidence is 7 per 100,000 people per year. The prevalence is highest in the Asian population and lowest in the African population. It is ten times more common in women and is usually diagnosed during middle age (40s) or after menopause. Older adults tend to have more severe symptoms of dry eyes and dry mouth; however, this is due to confounding factors such as adverse effects of medications, age-related fibrosis, and atrophy of secreting tissues. 

Pathophysiology 

The pathophysiology of SS is thought to be a multifactorial process. Autoantibodies in genetically predisposed individuals are triggered by environmental factors such as viral infection, which result in B-cell stimulation and chronic inflammation of the salivary and lacrimal glands. 

Multiple polymorphisms are associated with SS, the most common haplotype being HLA-DR3, but there are also associations with HLA-B8 and HLA-DQ2. The most common viral association is Epstein-Barr virus (EBV). However, HTLV-1, HIV and Hepatitis C have also been noted to have associations with SS. The presence of autoantibodies such as Anti-Ro/SSA and Anti-La/SSB are found in 60-80% of individuals affected with SS.