Value of combined application of the OMERACT scoring system and shear wave elastography for primary Sjögren's syndrome.

Objective: To assess diagnostic efficiency when introduce the OMERACT scoring system and shear wave elastography (SWE) into ACR/EULAR criteria for primary Sjögren's syndrome (pSS).

Methods: One hundred fifteen patients with suspected pSS were enrolled, including 71 pSS and 44 non-pSS patients. Salivary gland ultrasonography (SGUS) was performed on parotid glands (PG) and submandibular glands to obtain the OMERACT scores (range 0-3 for single gland) and SWE values, and diagnostic efficiency was evaluated.

Results: Receiver operating characteristic curves showed that the total OMERACT score of four glands and PG SWE had optimal predictive value for pSS (area under the curve (AUC) = 0.848, 0.852), with cutoff values of 8 and 6.8 kPa, sensitivities of 76.1% and 80.3%, specificities of 86.4% and 81.8%. In addition, the total OMERACT score of 10 and PG SWE value of 9.1 kPa were chosen to get high specificities (97.7% for both). By combining SGUS with current items except labial salivary gland biopsy (LSGB), a modified model was proposed. The modified model significantly distinguished pSS patients form non-pSS patients (AUC = 0.963), provided a sensitivity of 97.2% and specificity of 84.1%. It showed an excellent agreement with ACR/EULAR criteria (Kappa = 0.831, p < 0.001), and no statistical difference in diagnostic performance was observed (p = 0.180).

Conclusion: An ultrasound-integrated diagnosis model with comparable diagnostic efficiency was established by introducing the OMERACT scoring system and SWE. SGUS is a viable non-invasive adjunct for pSS and has potential to reduce reliance on LSGB for patients with negative anti-SSA/Ro. Key Points • Introducing the OMERACT scoring system and SWE into ACR/EULAR criteria had no negative effect on efficiency. • Inclusion of SGUS in the classification criteria may help reduce invasive LSGB.