Background An early and accurate diagnosis of Sjögren's Syndrome is an important factor in limiting complications of the disease. Achieving this diagnosis has historically proved challenging, requiring a number of diagnostic tests including serology . The utility of the traditional serological markers (SSA/Ro, SSB/La, Antinuclear Antibody, Rheumatoid Factor) have several limitations, including a combined sensitivity and specificity of approximately 40–60%, lack of detectability in approximately 20–30% of cases, lack of detectability early in the disease process, and lack of target-organ specificity [1,2].
Sjö™ is an advanced diagnostic panel for the early detection of Sjögren's Syndrome. It includes the traditional biomarkers as well as three novel, proprietary biomarkers (SP-1, CA6, PSP) that provide high sensitivity and specificity for Sjögren's Syndrome, are target-organ specific and appear early in the disease process [3,4].
Objectives To Evaluate the sensitivity and specificity of the advance Sjö panel in comparison to the traditional serological markers.
Methods Antibodies to the traditional markers (SSA [Ro], SSB [La], antinuclear antibody [ANA], and rheumatoid factor [RF]) and the novel biomarkers (salivary protein-1 [SP1], carbonic anhydrase-6 [CA6] and parotid secretory protein [PSP]) in patient sera samples were detected using the Sjö panel. To assess sensitivity, sera samples from 267 confirmed SS patients across 3 clinical studies were analyzed with Sjö. To assess specificity, sera samples from 125 age- and sex-matched controls, as well as 64 pediatric controls, were analyzed with Sjö.
Results Overall, the cumulative sensitivity of the complete Sjö panel was 91.4% (244/267); sensitivity of SSA/SSB alone was 74.9% (200/267), while sensitivity for the novel biomarkers alone was 49.8% (133/267). The cumulative specificity for the complete Sjö panel was 79.8% (151/189), and the cumulative specificity for the novel biomarkers was 83.5% (158/189).
Conclusions An early and accurate diagnosis of SS is an important factor in limiting complications of the disease. The Sjö panel incorporates traditional and novel markers and increases the sensitivity in the diagnosis of SS by over 25% without compromising specificity. Patients who may have SS would benefit from screening with the Sjö panel to facilitate early diagnosis and contribute to better management of dry eye symptoms and other systemic manifestations.
Sjogren Syndrome Foundation. Available at Http://www.sjogrens.org
Ramos-Casals M, Brito-Zerόn P, Sisό-Almirall A, Bosch X. Primary Sjögren's Syndrome. BMJ 2012;344:e3821 doi: 10. 1136/bmj.e382
Shen L, Suresh L, Lindemann M, Xuan J. Kowal P, Malyavantham K. Ambrus JL. Novel autoantibodies in Sjogren's syndrome. Clin Immunol 2012:145;251–25
Shen, L., Kapsogeorgou, E. K., Yu, M., Suresh, L., Malyavantham, K., Tzioufas, A. G,.Ambrus, J. L., Jr. Evaluation of salivary gland protein 1 antibodies in patients with primary and secondary Sjogren's syndrome. Clin Immunol 2014: 155; 42–465.
Suresh, L., Malyavantham, K., Shen, L., Ambrus, J. L., Jr. Investigation of novel autoantibodies in Sjogren's syndrome utilizing Sera from the Sjogren's international collaborative clinical alliance cohort. BMC Ophthalmol 2015, 15;38–42
Disclosure of Interest None declared