The most useful laboratory tests for confirming a diagnosis of Sjögren's syndrome include detection of specific autoantibodies such as anti-Ro/SSA and anti-La/SSB antibodies, which are considered hallmark serological markers. These antibodies help differentiate Sjögren's syndrome from other autoimmune conditions and are integral to classification criteria NICE CKS. Additionally, antinuclear antibody (ANA) testing is commonly positive in Sjögren's syndrome, supporting the autoimmune nature of the disease. Rheumatoid factor (RF) is also frequently elevated and can aid diagnosis, especially when combined with other serological markers NICE CKS. Complement levels (C3 and C4) may be reduced in active disease, reflecting immune complex activity, although these are less specific. In some cases, salivary gland biopsy remains a key diagnostic tool, but laboratory tests are essential initial steps.
Recent literature emphasizes advances in laboratory diagnostics, including improved sensitivity and specificity of anti-Ro/SSA and anti-La/SSB assays, and highlights challenges in seronegative cases where these antibodies are absent Li et al. 2025. In such cases, additional markers and clinical correlation are necessary Lenti et al. 2022. Overall, the UK guidelines prioritize anti-Ro/SSA and anti-La/SSB antibody testing as the cornerstone laboratory confirmation, supported by ANA and RF, with complement levels providing adjunctive information NICE CKS Li et al. 2025Lenti et al. 2022.
Key References
- CKS - Dry eye disease
- NG20 - Coeliac disease: recognition, assessment and management
- CKS - Palliative care - oral
- NG95 - Lyme disease
- NG12 - Suspected cancer: recognition and referral
- (Egner, 2000): The use of laboratory tests in the diagnosis of SLE.
- (Lenti et al., 2022): Seronegative autoimmune diseases: A challenging diagnosis.
- (Li et al., 2025): Advances in laboratory diagnosis of Sjogren's disease in children.