RElevance of UltraSonography for Assessing Salivary Gland Involvement in Systemic Sclerosis (SSc)

RElevance of UltraSonography for Assessing Salivary Gland Involvement in Systemic Sclerosis (SSc)

As fibrosis of salivary glands is supposed to be the main mechanism involved in Systemic sclerosis (SSc)-associated sicca syndrome, Ultrasonography , biopsy and measuring gland elasticity (by ARFI (Acoustic Radiation Force Impulse)) in SSc patients could also constitute a relevant method to assess the potential alterations of echostructure of major salivary glands and the fibrosis of Salivary Glands in this disease.

Systemic sclerosis (SSc) is a rare autoimmune chronic disorder characterised by vascular hyper-reactivity and fibrosis of the skin as well as internal organs. Intimal hyperplasia, endothelial dysfunction and occlusive vasculopathy are the underlying basis of these chronic vascular damages. The expression of the vasculopathy especially includes Raynaud phenomenon (RP), digital ulcers (DUs), gastro-intestinal involvement and pulmonary arterial hypertension (PAH). Sicca syndrome is clinically characterised by dryness of the eyes (xerophthalmia) and mouth (xerostomia). The prevalence of sicca symptoms is up to 70% in prospective series of SSc patients. Sicca syndrome is supposed to be primarily related to glandular fibrosis. The prevalence of primary Sjögren Syndrome (pSS) among SSc patients, as defined by the American-European Consensus Group criteria is around 15%. Sicca syndrome is therefore a frequent feature in SSc and constitutes an important cause of quality of life's impairment in SSc If studies have already evaluated clinical and histological alterations of minor salivary glands secondary to sicca syndrome in SSc , only few studies used the recent ACR(American College of Rheumatology) 2013 classification criteria for SSc to select patients. SGUS(Salivary Gland UltraSonography) evaluation in SSc has never been assessed to date. Potential alterations of MSG (Major Salivary Gland) echostructure in SSc have never been described to date. The performances and reliability of SGUS to assessed MSG involvement in SSc are still to be determined. As fibrosis of salivary glands is supposed to be the main mechanism involved in SSc-associated sicca syndrome, measuring salivary-gland elasticity using ARFI-ultrasonography in SSc patients could also constitute a relevant method to assess the fibrosis of MSG in this disease. A cross-sectional pilot study is therefore needed to explore these relevant questions about sicca syndrome in SSc.

Inclusion Criteria:

• Patients over eighteen years old;
• Fulfilling 2013 ACR classification criteria for Systemic sclerosis (Van den Hoogen et al. 2013);
• 60 patients with subjective sicca symptoms reported by a standardised questionnaire (Vitali C et al. 2002);
• 15 patients without sicca symptoms;
• Who has signed an informed consent
• Benefiting from a social security scheme

Exclusion Criteria:

• Treatment: current (or in the past 6 months) immunosuppressive treatment by rituximab or cyclophosphamide (representing less than 5% of SSc patients in the investigator's centres);
• Current (or in the past 6 months) treatment with drugs with anti-cholinergic properties (Selective Serotonin Reuptake Inhibitors and anti-histaminic inhibitors (hydroxyzine));
• Current treatment with antiplatelet aggregates
• Anti-vitamin K treatment (increasing risk of bleeding during minor salivary gland biopsy); and oral anti-coagulant
• Known abnormal coagulation (prolonged aPPT(activated partial thromboplastin time) and / or PT (Prothrombin time ( <70%)), or known thrombocytopenia (<150,000 platelets / mm3)
• Known secondary sicca symptoms : history of head-and-neck radiotherapy, hepatitis C infection, AIDS, sarcoidosis, amyloidosis, graft-vs-host disease and IgG4(Isotype's immunoGlobulin G4)-related disease;
• Pregnancy or breastfeeding mothers;
• Known intolerance/allergy to xylocain injection;
• Adults legally protected (under judicial protection, guardianship, or supervision), inability to consent.