Primary Sjogren's Syndrome: Diagnostic and Prognostic Value of Salivary Gland Ultrasonography Using a Simplified Scoring System

Objective. To determine the usefulness and prognostic value of a simplified salivary gland ultrasonography (SGUS) scoring system in primary Sjogren's syndrome (SS). Methods. Patients with primary SS (n = 105) and controls (n = 57) were evaluated using a simplified SGUS scoring system. Parenchymal homogeneity in salivary glands was graded from 0 to 3, with grades 0 (normal) and 1 (mild inhomogeneity) being interpreted as normal or unspecific, and grades 2 (several rounded) and 3 (numerous or confluent hypoechoic lesions) as primary SS typical. Associations between SGUS and clinical, histologic, and laboratory disease characteristics were analyzed. Results. The characteristic hypoechoic lesions (score 2 or 3) were found in 52% of primary SS patients and in 1 (1.8%) of controls (P < 0.001). Specificity and positive predictive value of abnormal SGUS for primary SS were both 98%, sensitivity and negative predictive values were 52% and 53%, respectively. Age or disease duration did not influence the SGUS result. Dryness did not differ between normal or abnormal SGUS. However, patients with pathologic SGUS had significantly more often signs and symptoms of systemic complications, higher disease activity, and more frequently markers of lymphoma development, such as salivary gland swelling, skin vasculitis, germinal center-like structures in salivary gland biopsy findings, and CD4+ T cell lymphopenia. Conclusion. SGUS using a simplified score for assessment of parenchyma dyshomogeneity is highly specific for primary SS and offers the advantage of identifying patients with severe disease or at risk of lymphoma. However, early disease may be missed. SGUS is easy and rapidly performed and may be considered as an item in future modified classification criteria.