Importance of salivary gland focus score in the diagnosis of Sjögren's syndrome

Abstract

To explore the correlation between labial salivary gland focus score (FS) and severity of Sjögren's syndrome patients. From January 2009 to December 2010, a total of 77 patients with primary Sjögren's syndrome were recruited to undergo minor salivary gland biopsy, Schirmer's test, unstimulated whole salivary flow, organ function and serological test. Focus score was calculated for all biopsy samples. And the correlation between focus score and serological test and organ function damage was evaluated. Their pathological examinations revealed focal lymphocytic sialadenitis (n = 62), 10 cases with non-specific or sclerosing chronic sialadenitis (n = 10) and normal features (n = 5). Among 62 cases with focal lymphocytic sialadenitis, 46 cases had FS ≥ 1 and another 16 FS < 1. The median FS was 2.4 ± 2.5 . FS ≥ 1 was strongly associated with unstimulated whole salivary flow rates and ocular staining score (P < 0.05), but not significantly with dry mouth or eyes. FS was significantly correlated with serum immunoglobin G (IgG), immunoglobin M (IgM) and rheumatoid factor level (P < 0.05). Those with positive anti-SSA had higher FS level than those with negative anti-SSA antibody (P < 0.05). In addition, FS level was not significantly associated with organ function damage. Prior to determining FS, distinguishing focal lymphocytic sialadenitis from other types of sialadenitis is essential in assessing salivary gland biopsy. And the FS level might be associated with disease activity and positive anti-SSA. No correlation exists between FS and organ function damage.