The clinical phenotype of primary Sjögren’s syndrome patients with lymphadenopathy

Abstract

Objective Previous cohort studies have shown that around 10% of patients with primary Sjögren’s syndrome (pSS) develop lymphadenopathy during their disease course. However, no studies have described their clinical phenotype. The present study aims to describe the clinical manifestations and laboratory findings of pSS patients presenting long-standing lymphadenopathy. Methods From a total of 1234 consecutive pSS patients fulfilling the 2016 ACR-EULAR criteria, those with stable lymphadenopathy unrelated to lymphoma were identified (lymphadenopathy group). Their clinical data were collected and compared with 2 control groups: a) the remaining unmatched pSS patients without lymphadenopathy (unmatched non-lymphadenopathy group) and b) pSS patients without lymphadenopathy matched for age, sex, and disease duration, in an approximately 1:1 ratio (matched non-lymphadenopathy group). Results One hundred and sixty-five (13.37%) patients presented persistent, stable lymphadenopathy. They were characterised by younger age at both pSS onset and diagnosis, and by shorter disease duration. Compared to the unmatched non-lymphadenopathy group, patients with lymphadenopathy had more frequently salivary gland enlargement (p<0.001), higher focus score at first salivary gland biopsy (p=0.017), palpable purpura (p<0.001), peripheral nervous system involvement (p=0.012), glomerulonephritis (p<0.001), and leukopenia (p<0.001), while the results of the matched comparison were similar. Regarding the serological profile, the comparison with the unmatched group demonstrated higher frequency of ANA (p=0.013), anti-Ro/SSA (p=0.001), and anti-La/SSB (p<0.001) positivity for the lymphadenopathy group, while in the matched comparison only higher rates of anti-Ro/SSA positivity (p=0.002) remained statistically significant. Conclusion pSS patients presenting non-lymphoma related stable lymphadenopathy constitute a subgroup of younger individuals with B-cell hyperactivation.