Biopsy Results in Sjogren's Syndrome Save

A prospective study from the Netherlands analyzed the comparative value of simultaneous labial and parotid salivary gland biopsies performed in patients with sicca complaints and suspected Sjogren's syndrome (SjD).

Researchers from the University Medical Center Groningen compared the focus score (FS) and other histopathologic features from 99 SjS patients, between 2014 and 2017. FS is defined as the number of foci per 4 mm2 of salivary gland tissue. An FS ≥ 1 indicates a positive diagnosis of SjS.

Three experts diagnosed SjD in one-third (n=36) and 63 others with as having non-SjD sicca. 

Overall agreement with between labial and parotid biopsies was high; 80% for focus scores, 89% for germinal centers, 84% for the immunoglobulin (Ig) A/IgG plasma cell shift, and 93% for pre-lymphoepithelial lesions (LELs). 

More labial gland biopsies had a FS ≥ 1 compared with their parotid biopsies (P = .012) in both the SjS and non-SjS sicca populations, indicating that labial gland biopsies are more likely to show inflammation.  When considering only SjD patients, labial glands contained significantly less B-lymphocytes, GCs/mm² and less severe LELs compared with parotid glands.    

In SjS patients, the parotid biopsies were more likely to have higher absolute B-lymphocyte count, germinal centers and pre-lymphoepithelial lesions (compared to labial biopsies), suggesting B-lymphocyte hyperactivity.

Both labial and parotid glands can be used for diagnosis and classification of SjD. Yet there is a skew towards more B cell activity in parotid salivary glands and inflammation in the labial glands.