The prevalence of sicca symptoms and sjogren's syndrome in patients with systemic sclerosis and expression of ?lfa?smooth muscle actin in salivary gland biopsy specimens

Objective:Systemic sclerosis (SSc) is a heterogeneous systemic disorder characterized by massive deposition of collagen and other matrix substances in connective tissue. Although sicca symptoms are thought to be a frequent complaint associated with SSc, pathogenesis of salivary hypofonction is not defined clearly and little is known about how often they occur. The aim of this study was to determine the prevalence and contributing factors of sicca symptoms and Sjogren?s syndrome (SjS) in patients with SSc, and also to evaluate to expression of the ?-smooth muscle actin (??SMA), a myofibroblast marker, in salivary gland specimens.Method:Consecutive 102 SSc patients [91 female (89%), mean age 52,5 ± 12 years] followed by an outpatient rheumatology clinic were included in the study. The systematic first-line clinical evaluation included a questionnaire specific for the subjective presence of xerophthalmia and xerostomia based on the revised American?European Consensus Group criteria for SS, together with the Schirmer I test and unstimulated whole salivary flow. If the findings of the first-line clinical evaluation were positive a labial salivary gland biopsy was performed. Salivary glandular tissue sections were evaluated for the presence of focal lymphocytic sialadenitis (a focus score?1), and glandular fibrosis. Immunohistochemistry was used for the expression of ??SMA.Results:Of 102 patients, 85 (83%) had limited SSc (lSSc), 12 (%12) diffuse SSc (dSSc) and 5 (5%) had sine scleroderma. Seventy-six patients (75%) had sicca syndrome (65 [64%] had xerostomia, and 49 [48%] had xerophthalmia). Sixty-five of the 102 patients (64%) had positive findings on the Schirmer test and 36 (35%) patients had positive salivary flow test. A total salivary gland biopsy was indicated in 90 patients according to our protocol. Six patients refused the procedure therefore biopsy were performed in eighty-four (82%) patients. On histopathologic examination of biopsy samples; fibrotic lesion were observed in 67 out of 84 (80%) and in 38 (45%) sample focus score was ?1. Thirty-six patients (35,3%) fulfilled American European Consensus Group criteria for secondary SjS. Thirty-four patients who diagnosed secondary SjS had lcSSc and two of them had sine scleroderma. Secondary SjS were associated with age, age at onset of disease and the presence of SS-A antibody. Multivariate analysis revealed that SS-A antibody positivity, age were significant predictor for SjS (p=0,015, p=0,038). In immunohistochemistry examination only 7 sample were stained poorly for ?-SMA.Conclusion:Despite fibrosis seems to be the main cause of sicca symptoms, our study revealed one of the highest prevalence of SjS in patients with SSc. These results suggest that limited cutaneous subtype of SSc carries a greater risk for SjS. Our study also suggested that myofibroblastic transformation may not be the only factor for fibrosis seen on minor salivary glandular tissue.