CD27(-)CD38(low)CD21(low) B-Cells Are Increased in Axial Spondyloarthritis

B-cells have received little attention in axial spondyloarthritis (axSpA) and for this reason their role in pathogenesis remains unclear. However, there are indications that B-cells may be involved in the disease process. Our objective was to obtain insights into the composition of the peripheral B-cell compartment of axSpA patients compared to healthy donors (HD) and patients with primary Sjögren’s syndrome (pSS), a typical B-cell-associated autoimmune disease. Special emphasis was given to CD27-negative B-cells expressing low levels of CD21 (CD21(low) B-cells), since this subset is implicated in autoimmune diseases with strong involvement of B-cells. Transitional B-cells (CD38(hi)) were excluded from the analysis of the CD27(-)CD21(low) B-cell compartment. This study included 45 axSpA patients, 20 pSS patients and 30 HDs. Intriguingly, compared to HDs the frequency of CD27(-)CD38(low)CD21(low) B-cells was significantly elevated in both axSpA and pSS patients (P<0.0001 for both comparisons). The frequency of CD27(-)CD38(low)CD21(low) B-cells expressing the activation-induced immune markers T-bet and CD11c was decreased in axSpA patients compared to HDs. A higher proportion of CD27(-)CD38(low)CD21(low) B-cells expressed the chemokine receptor CXCR3 in axSpA compared to HDs, suggestive for active involvement of these cells in an inflammatory process. The frequency of CD27(-)CD38(low)CD21(low) B-cells in axSpA patients correlated positively with age and erythrocyte sedimentation rate. Furthermore, axSpA patients with extra-skeletal manifestations (ESM) showed increased frequencies of CD27(-)CD38(low)CD21(low) B-cells compared to patients without ESM. In conclusion, our findings are suggestive of active B-cell involvement in the pathogenesis of axSpA, against prevailing dogma

Incorporation of Salivary Gland Ultrasonography Into the American College of Rheumatology/European League Against Rheumatism Criteria for Primary Sjögren's Syndrome

Objective: To assess whether the addition of salivary gland ultrasonography (SGUS) or replacement of current criteria items by SGUS influences the performance of the American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria for primary Sjögren's syndrome. Methods: Included were consecutive patients with complete data on all ACR/EULAR items (n = 243) who underwent SGUS in our primary Sjögren's syndrome expertise center. Clinical diagnosis by the treating physician was used as the gold standard. Separate analyses were performed for patients who underwent labial or parotid gland biopsies. The average score for hypoechogenic areas in 1 parotid and 1 submandibular gland was determined (range 0–3). Next, performance of the ACR/EULAR criteria was evaluated after addition of SGUS or replacement of current items by SGUS. Results: Receiver operating characteristic analysis showed an optimal cutoff value of ≥1.5 for SGUS. The optimal weight for SGUS positivity was 1. Cutoff for ACR/EULAR fulfilment remained ≥4. In patients who underwent a labial gland biopsy (n = 124), the original criteria showed an area under the curve (AUC) of 0.965, sensitivity of 95.9%, and specificity of 92.2%. After the addition of SGUS, the AUC was 0.966, with a sensitivity of 97.3% and specificity of 90.2%. In patients who underwent a parotid gland biopsy (n = 198), similar results were found. Sensitivity of the criteria decreased substantially when SGUS replaced salivary gland biopsy or anti-SSA antibodies, while performance remained equal when SGUS replaced the ocular staining score, Schirmer's test, or unstimulated whole saliva flow. Conclusion: Validity of the ACR/EULAR criteria remains high after incorporation of SGUS. With SGUS, clinicians are offered a larger array of tests to evaluate fulfillment of the ACR/EULAR criteria

FDG-PET/CT discriminates between patients with and without lymphomas in primary Sjögren's syndrome

OBJECTIVES: To assess the usefulness of FDG-PET/CT 1) to discriminate between pSS patients with and without lymphomas and 2) to evaluate systemic disease activity in pSS.METHODS: ACR-EULAR-positive pSS patients who underwent FDG-PET/CT were included. Scans were visually evaluated and quantitative analysis was performed by measuring standardized uptake values (SUV) of salivary and lacrimal glands and systemic regions. ROC analyses were performed to find SUV cut-off values to discriminate between lymphoma and non-lymphoma.RESULTS: 26 of the 70 included patients were diagnosed with a pSS-associated lymphoma, mostly of the mucosa associated lymphoid tissue type (23/26). Lymphoma patients showed higher FDG-uptake in the parotid and submandibular glands, and more frequently showed presence of nodular lung lesions, compared with non-lymphoma patients. The accuracy of the maximum SUV (SUVmax) in the parotid and submandibular gland to predict lymphoma diagnosis was good, with optimal cut-off points of 3.1 and 2.9. After combining these three visual and quantitative findings (nodular lung lesions, parotid SUVmax &gt; 3.1 and submandibular SUVmax &gt; 2.9), sensitivity was 92% when at least one of the three features were present, and specificity was 91% in case at least two features were present. Furthermore, FDG-PET/CT was able to detect systemic manifestations in pSS patients, mostly involving lymph nodes, entheses and lungs.CONCLUSIONS: FDG-PET/CT can assist in excluding pSS-associated lymphomas in patients without PET abnormalities, possibly leading to a decrease of invasive biopsies in suspected lymphoma patients. Furthermore, FDG-PET/CT is able to detect systemic manifestations in pSS and can guide to the best biopsy location.</p