High prevalence of salivary gland ultrasound abnormalities in systemic sclerosis

Abstract

Objective: To evaluate salivary gland (SG) involvement in patients with systemic sclerosis (SSc) using SG ultrasound (SGUS).

Methods: Patients with SSc (n=62), primary Sjögren's syndrome (pSS) (n=59), and idiopathic Sicca syndrome (n=43) were evaluated using the outcome measures in rheumatology clinical trial (OMERACT) definitions of the SGUS scoring system. The hyperechogenic bands using the 0-3 scoring system, intraglandular power Doppler signal (PDS), and SG volumes were also assessed.

Results: The proportion of patients with OMERACT grades (≥2) among the four SGs was significantly higher in SSc (51.6%) and pSS (62.7%) groups than those in the idiopathic Sicca syndrome group (4.7%). Patients with SSc and pSS had significantly higher total fibrosis grades than controls. No difference in fibrosis grades was observed between SSc and pSS groups. The PDS scores of SGs were higher in the SSc group than in the idiopathic Sicca syndrome group. SG volumes did not differ between the groups. SSc patients with SGUS grades ≥2 had more anti-centromere antibodies (ACA) (65.6% vs. 30.0%) than individuals with grades 0-1. SSc patients with fibrosis grades ≥2 reported more Sicca symptoms than those with grades 0-1. Inhomogeneity and hyperechogenic bands within the SGs were not associated with organ involvement in SSc.

Conclusions: More than half of patients with SSc, specifically with ACA, showed SG involvement. SG fibrosis was more prominent in SSc than in idiopathic Sicca syndrome and was associated with subjective Sicca symptoms. However, hyperechoic bands within the SGs are not features that can differentiate between SSc and pSS.

Keywords: Salivary glands; Sjögren's syndrome; Systemic sclerosis; Ultrasonography.