Objective: To evaluate the relevance of the blood B-cell subset profile to the diagno-sis of Sjögren’s syndrome (SS).
Methods: The distribution of mature blood B cells from Bm1 through Bm5 was de-termined in 161 patients, of whom 25 fulfilled the American-European Consensus Group criteria for primary SS (pSS), and 136 served as disease controls.
Results: The percentage of Bm2 and Bm2' cells was increased in the pSS patients compared with the 54 rheumatoid arthritis (RA) and the 18 systemic lupus erythemato-sus (SLE) patients (p<10-4 for the 2 comparisons). In contrast, those of early Bm5 (eBm5) and Bm5 were decreased in pSS patients, compared with RA, and SLE pa-tients (p<10-4 for the 2 comparisons). The receiver-operating characteristic curves al-lowed for optimizing cut-off value of Bm2+Bm2’ cells at 71.1% for 88.0% sensitivity (Se) and 83.1% specificity (Sp), that of Bm5+Bm5 cells at ≤ 13.5% for 84.0% Se and 83.1% Sp, and consequently that of Bm2+Bm2'/eBm5+Bm5 at ≥ 5 for 88.0% Se and 84.6% Sp.
Conclusion: Given its presentation as a signature for pSS, relative to RA and SLE, such a distribution of B-cell subsets might provide a useful diagnostic tool.