A Stratification Approach Based on Salivary Gland Ultrasonography for Assessing Secretory Function in Sjögren's Disease.

Abstract

Our aim was to develop an ultrasonographic scoring model for staging hypofunction of salivary gland (SG) in patients suffering from Sjögren's disease (SjD). The assessment of SG secretory hypofunction was conducted by measuring whole salivary flows. B-mode ultrasonography was performed bilaterally on the parotid and submandibular glands to evaluate the Gland score and OMERACT score quantitatively. The correlation between these scores and SG secretory function in SjD patients was analyzed, leading to the development of an ultrasonographic scoring model for staging SG hypofunction. A one-center derivation cohort comprising 164 SjD patients and a double-center validation cohort consisting of 107 SjD patients were included. Both ultrasonographic scores demonstrated excellent discriminatory ability between SjD patients with hypofunction and those with normal function (both AUC>0.8, p<0.001). A novel ultrasonographic scoring model revealed that low total OMERACT scores (<5) indicated initial-stage SG hypofunction, while high scores (>9) suggested end-stage hypofunction. Conversely, patients with moderate-level total OMERACT scores (5~9) require further stratification using total Gland scores. The incidence of SG hypofunction among all 271 SjD patients was found to be 18% in the initial stage, 58% in the progressive stage, and 100% in the end stage (p<0.001). Furthermore, the incidence of lacrimal gland involvement and hyperglobulinemia (IgG>16 IU/mL) was significantly lower in the initial-stage patients compared to those at other stages (all p<0.001). The novel ultrasonographic scoring model incorporates precise definitions for each stage, providing a robust and clinically significant approach to stratify salivary gland secretory hypofunction in SjD.