Noninvasive Score in Classification Diagnosis of Sjögren's Syndrome

Abstract

Background: To develop simple, practical classification criteria for Sjögren's Syndrome (SS) without Labial Salivary Gland Biopsy (LSGB). Methods: In the new criteria (noninvasive score, NIS) set, classification as “definite SS” is based on the ocular and oral symptoms and signs, autoantibodies and the existence of autoimmune thyroid disease, which were calculated. Patients with a score ≥5 were classified as having definite SS and patients with a score <4 were supposed to be excluded from SS. For the patients with a score of 4, LSGB was suggested. Result: 76 patients with suspected SS were recruited between April 2013 and September 2014, 42 of which were definitive diagnosis of SS and 34 were excluded from SS. Sensitivity and specificity for the NIS criteria in the diagnosis of SS were 97.6% and 94.1%, respectively. The Negative Predictive Value (NPV) and Positive Predictive Value (PPV) to detect SS were 97.0% and 95.3% respectively, and the diagnostic accuracy was 96.1%. The area under the ROC curves (AUC; 95% CI) for NIS criteria was 0.959 (0.905-1.000), which performed better than the American-European Consensus Group’s (AECG) criteria and LSGB in the diagnosis of SS (P < 0.05). Conclusion: The NIS criteria are an alternative to the AECG criteria in classification diagnosis of SS, which are with high diagnostic efficiency. We recommend using a score <4 and ≥5 to rule out or to diagnose SS respectively. For the patients with a score of 4, LSGB is necessary and able to diagnose SS.