Background:Primary Sjögren’s syndrome (pSS) is a chronic autoimmune disease that affects exocrine systems. Xerostomia is one of representative clinical features which contributes to an accelerated destruction of the mucosal epithelium. Atrophic lesions of the oral mucosa is a common observation in pSS cases.Objectives:To develop a modified ultrasonography scoring system which included the buccal mucosa and major salivary glands in patients with pSS and assess the ultrasonography characteristics of buccal mucosa.Methods:Ultrasonography of buccal mucosa and major salivary glands were conducted for 53 pSS patients and 44 patients with SS-related manifestation but without pSS. The thickness of buccal mucosa and the echogenicity of the buccal mucosa were scored using the 0-2 scoring system. The sonographic features of major salivary glands were scored using the 0-16 scoring system. Differences of buccal mucosa thickness between groups were compared with Mann-Whitney test. The 2 methods (0-16 scoring system, modified 0-18 scoring system) were compared and statistical cutoffs were identified using receiver operating characteristic (ROC) curve analysis.Results:The thicknessr the pSS group was significantly thinner than that for the non-pSS group (p< 0.001), and the best score cut-off was 0.38mm. The echogenicity of buccal epithelium was heterogeneously hyperechoic in 32 (60.4%) of the 53 patients, and was 5(11.4%) of the control group. The optimal cutoff point to distinguish between pSS and non-pSS was 7 in the modified scoring system (sensitivity 79.2%, specificity 95.5%), and it was 6 in the 0-16 system (sensitivity 81.1%, specificity 86.4%). Compared with the 0-16 system, modified scoring system improved the diagnostic specificity.Conclusion:The thickness of the oral mucosa in patients with pSS is thinner and the echogenicity in buccal epithelium increases compared with that of non-pSS. The modified ultrasonography scoring system integrated oral mucosa and major salivary glands is able to improve the diagnostic specificity of patients with pSS.Figure 1.Ultrasonography image of the normal buccal tissue. E = epithelial membrane of buccal mucosa; ST = subepithelial connective tissue; M = buccinator muscle.Figure 2.Ultrasonography image of pSS patient reveals decreased thickness and heterogeneous hyperechogenicity of buccal mucosa. E = epithelial membrane of buccal mucosa; ST = subepithelial connective tissue; M = buccinator muscle.References:[1]Belkacem Chebil R, Oueslati Y, Marzouk M, Ben Fredj F, Oualha L, Douki N. Oral Lichen Planus and Lichenoid Lesions in Sjögren’s Syndrome Patients: A Prospective Study. Int J Dent. 2019:1603657.[2]De Vita S, Lorenzon G, Rossi G, Sabella M, Fossaluzza V. Salivary gland echography in primary and secondary Sjögren’s syndrome. Clin Exp Rheumatol 1992;10(4):351-6.[3]Liu Y, Zhu J, Guo H, Li W, Li J, Wang Y, et al. Buccal Mucosa Assessed by Ultrasonography in Healthy Adults: Methodology and Determination of Normal Appearance. Ultrasound Med Biol. 2019;45(5):1297-1305.Acknowledgments:This work was partly supported by National Natural Science Foundation of China (No. 81571684)Disclosure of Interests:None declared
Diagnostic performances of ultrasound evaluation of major salivary glands according to the 2019 OMERACT US scoring system
