Diagnostic Performances of Ultrasound Evaluation of Major Salivary Glands According to the 2019 Outcome Measures in Rheumatology Ultrasound Scoring System.

OBJECTIVE

To evaluate the diagnostic performance of ultrasound examination of the salivary glands (US-SG) according to the 2019 Outcome Measures in Rheumatology (OMERACT) US scoring system for Sjögren's syndrome (SS).

METHODS

The present work was a retrospective study based on a multicentric cohort with SS/sicca syndrome. The American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) 2016 classification criteria for SS (a score of ≥4 without ocular staining score), the American-European Consensus Group (AECG) 2002 classification criteria, and clinician experts were considered as reference standards for diagnosis of SS. An OMERACT score of ≥2 according to 2 independent readers defined the diagnosis of SS based on US-SG assessment. Diagnostic performances and interobserver reproducibility of US-SG were assessed.

RESULTS

Forty-two patients fulfilling the ACR/EULAR 2016 criteria for SS were compared to 30 control subjects with sicca syndrome. Twenty-five patients were diagnosed as having SS according to US-SG evaluation, and they were more frequently observed in the SS group (52.5%) than in the control group (10.0%) (P < 0.001). US-SG showed an area under the curve (AUC) of 0.751 (95% confidence interval [95% CI] 0.621, 0.882) for the diagnosis of SS (ACR/EULAR 2016 classification). The inclusion of US-SG in the ACR/EULAR 2016 classification improved sensitivity (91.5% versus 89.4%) with limited decrease of specificity (96.0% versus 100%) and with an AUC of 0.975 (95% CI 0.945, 1.00). Similar results were observed when US-SG was included in the AECG 2002 classification criteria. Interobserver reproducibility of a score of ≥2 according to the 2019 OMERACT US scoring system for SS diagnosis was good (κ = 0.73 [95% CI 0.64, 0.81]). Histologic lymphocyte infiltration of the minor salivary glands was associated with the OMERACT grading of US-SG.

CONCLUSION

The present study confirms the good specificity of the 2019 OMERACT US classification measures of US-SG for the diagnosis of SS and its feasibility in daily practice.