Correlation between ultrasound imaging of major salivary glands and histopathological findings of labial gland biopsy samples in Sjogren's syndrome

Abstract

BackgroundUltrasound imaging has been recognised as a non-invasive, reproducible method for assessing the major salivary glands. The aim of this study was to investigate the relation between ultrasound imaging of major glands and focal lymphocytic score (FS) of minor salivary glands in Sjogren's syndrome. MethodsBiopsies of labial glands and ultrasound imaging of major glands were done on 196 patients (mean age 55 years, 19 male, 177 female) attending the Sjogren's Clinic at Guy's Hospital. FS of labial glands was judged by two histopathologists whose assessment was standardised. Ultrasonography was done with a single Philips-iU22 Ultrasound machine, and a disease severity score (US) was determined. Patients were categorised into three groups: those diagnosed with Sjogren's syndrome according to the American-European classification criteria (Sjogren's syndrome group), those with non-specific sialadenitis (sialadenitis group), and those with normal biopsy results (non-salivary gland disease group). FindingsThere was a highly significant correlation between FS and US scores (mean score 1·8 [SD 2·4, range 0–11·3] vs 2·7 [2·9, 0–9], r=0·665, n=196; p<0·0001). Mean FS and US scores for the Sjogren's syndrome group were significantly greater than for the sialadenitis group (p=0·0001). For the Sjogren's syndrome group, there was a significant correlation between FS and US scores (mean score 3·6 [SD 2·6, range 0–11·3] vs 5·0 [2·4, 0–9], r=0·395, n=87; p<0·0001). For the sialadenitis group, there was a significant correlation between FS and US scores (mean score 0·4 [SD 0·6, range 0–2·3] vs 1·1 [1·7, 0–7], r=0·321, n=66; p<0·005). No obvious correlation between FS and US scores existed for the non-salivary gland disease group (mean score 0·2 [SD 0·5, range 0–2·6] vs 0·5 [SD 1·2, 0–5], n=43). InterpretationThis is the first large-scale study to show the strong relation between US scores of major salivary glands, and FS scores of minor salivary glands, suggesting a uniform disease process. Ultrasound analysis proves to be an important methodology in management and studies of Sjogren's syndrome. FundingNational Institute for Health Research.