Background Real time sonoelastography (RTS) is a novel imaging option involving tissue stiffness assessment that might be a useful in primary Sjögren's syndrome (PSS).

Objectives To evaluate the stiffness of parotid and submandibular glands using RTS, and to correlate with a morphologic ultrasonographic (US) score, profibrotic chemokines and cytokines, and gland fibrosis among patients with PSS.

Methods We included 26 PSS patients with salivary gland biopsy within 5 years previous the US evaluation. B-Mode US and RTS (ARFI technique) were performed by a trained radiologist. Parotid and submandibular glands were individually rated for parenchymal echogenicity, homogeneity, hypoechogenic areas, hyperechogenic reflections and clearness of borders using the Hocevar scale (Global B-mode sum score 0–48 points). RTS was conducted at both parotid and submandibular glands (8 areas of each gland to obtain a median value) and then reported a median global RTS score in m/seg. We assessed the ESSDAI, ESSPRI, non-stimulated whole salivary flow rate (NSWSF), C3 and C4 levels, RF, anti-Ro/La antibodies and salivary levels of CXCL14, CCL28, TRAIL and TGb measured by ELISA. We also evaluated the presence of fibrosis in biopsies with the Masson's trichrome staining.

Results The mean age was 51.1±11 years, median disease duration of 6.1 years, 92.8% were females and 92.8% had oral symptoms. The global B-mode score was 22.2 points (13–44) and the RTS global score 2.5 (1.64–3.28) m/seg. We found a correlation between the RTS global score and the global B-mode score (t=0.53, p=0.001), the RTS global score between both parotids (t=0.58, p=0.0001) and both submandibulars (t=0.50, p=0.0001); but not between parotids and submandibular glands. The RTS global score correlated with the NSWSF (t=-0.53, p=0.001), ESSDAI (t=0.31, p=0.03), glandular ESDDAI domain (t=0.36, p=0.02), C4 levels (t=-0.32, p=0.04), but not with the rest of serological variables, chemokines and cytokines levels.

We found fibrosis in 7 patients (26.9%), and these patients were not different when compared to the group without it, regarding the RTS global score, B-mode global score, age and chemokine and cytokines levels, but tended to have a longer disease duration. At the linear regression analysis, the glandular ESSDAI domain (B=0.49, p=0.04), the C4 level (B=-0.02, p=0.05) and the disease duration (B=0.04, p=0.04) were associated with the RTS global score.

Conclusions The elastrographic evaluation correlated with the US morphologic score and glandular activity but not with fibrosis.

1. Dejaco C, De Zordo T, Heber D, et al. Real-time sonoelastography of salivary glands for diagnosis and functional assessment of primary Sjögren's syndrome. Ultrasound in Med & Biol 2014; 40:2759–67.

Disclosure of Interest None declared