|Title||Sjögren's Syndrome without focal lymphocytic infiltration of the salivary glands.|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||Sharma, R, Chaudhari, KS, Kurien, BT, Grundahl, K, Radfar, L, Lewis, DM, Lessard, CJ, Li, H, Rasmussen, A, Sivils, KL, R Scofield, H|
|Date Published||2019 May 15|
OBJECTIVE: Primary Sjögren's syndrome (SS) is characterized by a focal lymphocytic infiltrate in exocrine glands. We undertook this study to describe patients that lacked this key feature.
METHODS: We evaluated subjects with sicca in a comprehensive clinic at which medical, dental and ophthalmological examinations were performed. All subjects underwent a minor salivary gland biopsy with focus score calculation. Extra-glandular manifestations were also determined. We categorized subjects as high, intermediate, or low in terms of the expression of interferon-regulated genes.
RESULTS: About 20% (51 of 229, 22%) of those classified as primary Sjögren's syndrome had a focus score of zero. Compared to those with anti-Ro positivity and a focus score >1.0, the focus score zero patients (who by classification criteria must be anti-Ro positive) were statistically less likely to have anti-La (or SSB) and elevated immunoglobulin as well as less severe corneal staining. In addition, the focus score zero patients were less likely to have elevated expression of interferon-regulated genes in peripheral blood mononuclear cells than anti-Ro positive SS subjects with a focal salivary infiltrate.
CONCLUSION: There are only a few clinical differences between primary Sjögren's syndrome patients with focus score zero and those with both anti-Ro and a focus score >1.0. Nonetheless, the small subset of focus score zero patients tested did not have elevated expression of interferon-regulated genes, but did have systemic disease. Thus, extra-glandular manifestations are perhaps more related to the presence of anti-Ro than increased interferon. This may have relevance to Sjögren's syndrome pathogenesis.
|Alternate Journal||J. Rheumatol.|