Discriminatory Characteristics in Patients with Primary Sjögren’s Syndrome and Non-Sjögren

Objectives: To evaluate potential discriminatory systemic, oral and salivary characteristics in patients with primary Sjögren’s syndrome (pSS) and non-Sjögren’s syndrome (non-pSS).
Methods: Twenty-three patients referred for diagnosis of pSS underwent an interview including exocrine and non-exocrine symptoms and manifestations, an oral clinical examination, measurements of unstimulated (UWS) and chewing-stimulated (SWS) whole saliva flow rates, a labial salivary gland biopsy and a test for serum autoantibodies.
Results: Nine females (aged 57±8 years) fulfilled the American-European Consensus Classification Criteria, whereas 13 females and 1 male (aged 54±15 years) did not. No significant differences were found in symptoms of oral and ocular dryness, arthralgia, UWS flow rates, mean score of decayed-missed-filled-teeth/-surfaces, levels of plaque, gingival inflammation and probing depth. However, patients diagnosed with pSS had lower SWS flow rates (0.42±0.37 ml/min vs. 0.83±0.65 ml/min), more missing teeth (2±3 vs. 1±3), higher fatigue scores and presence of keratoconjunctivitis sicca (89% vs. 50%), fewer concomitant systemic diseases and lower intake of prescribed medication. Lymphocytic infiltration (i.e., focus score ≥1) were present in 4/9 (44%) salivary gland biopsies from patients with pSS and in none of those from non-pSS (mean focus score 2.9±5.2 vs. 0.01±0.03). In the remaining 56% of patients with pSS, the salivary gland tissue was characterized by atrophy, fibrosis and diffuse inflammation. All patients diagnosed with pSS had elevated levels of circulating anti-Ro/SSA serum autoantibodies as compared to only 3/14 (21%) in the non-pSS group.
Conclusions: Our preliminary findings indicate that non-pSS patients differentiate from pSS patients by having higher/normal SWS flow rates, which suggest a medication-induced salivary hypofunction corresponding to the higher medication intake in the non-pSS group. Oral, ocular and systemic symptoms and manifestations, and the presence of anti-Ro/SSA as well, are poor discriminatory characteristics. Our on-going study includes a larger cohort to substantiate findings and search for more specific biomarkers.