Increased Interferon Signalling in Vaginal Tissue of Patients With Primary Sjögren Syndrome.

OBJECTIVE: Vaginal dryness is an important factor influencing sexual function in women with primary Sjögren syndrome (pSS). Previous studies showed a higher degree of inflammation in vaginal biopsies from patients with pSS compared to non-pSS controls. However, the molecular pathways that drive this inflammation remain unclear. Therefore, the aim of this study was to investigate inflammatory pathway activity in the vaginal tissue of patients with pSS. METHODS: Vaginal biopsies of 8 premenopausal patients with pSS experiencing vaginal dryness and 7 age-matched non-pSS controls were included. Expression of genes involved in inflammation and tissue homeostasis was measured using NanoString technology and validated using TaqMan Real-Time PCR. Vaginal tissue sections were stained by immunohistochemistry for myxovirus resistance protein 1 (MxA) and CD123 (plasmacytoid dendritic cells [pDCs]). RESULTS: The most enriched pathway in vaginal biopsies from patients with pSS compared to non-pSS controls was the interferon (IFN) signaling pathway (P < 0.01). Pathway scores for Janus kinase and signal transducer and activator of transcription (JAK-STAT) and Notch signaling were also higher (P < 0.01 for both pathways). Conversely, transforming growth factor-ß signaling and angiogenesis pathway scores were lower in pSS (P = 0.02 and P = 0.04, respectively). Differences in IFN signaling between patients with pSS and non-pSS controls were confirmed by PCR and MxA tissue staining. No CD123+ pDCs were detected in vaginal biopsies. IFN-stimulated gene expression levels correlated positively with CD45+ cell numbers in vaginal biopsies and serum anti-SSA/Ro positivity. CONCLUSION: Upregulation of IFN signaling in vaginal tissue of women with pSS, along with its association with tissue pathology, suggests that IFNs contribute to inflammation of the vaginal wall and potentially also to clinical symptomatology (ie, vaginal dryness).

Increased Diagnostic Accuracy of the Labial Gland Biopsy in Primary Sjögren Syndrome When Multiple Histopathological Features Are Included.

OBJECTIVE: The aim of this study was to evaluate the diagnostic accuracy of the labial salivary gland biopsy based on multiple histopathological features in patients with suspected primary Sjögren syndrome (pSS). METHODS: Patients from a diagnostic sicca cohort with clinically suspected pSS who underwent a labial gland biopsy were included. Patients were categorized as having pSS or non-Sjögren syndrome sicca (non-SS sicca) based on vignettes scored by an expert panel. Labial gland biopsies were analyzed for the presence of four histopathological features: focus score (FS) ≥1, prelymphoepithelial and lymphoepithelial lesions, immunoglobulin G plasma cell shift, and germinal centers. Sensitivity and specificity of histologic features were calculated, and the optimal cutoff value for the number of histopathological features needed to diagnose pSS was determined with receiver operating curve analysis. RESULTS: A total of 38 patients were categorized as having pSS and 65 as having non-SS sicca. In labial gland biopsies of patients with pSS, the prevalence of FS ≥1 was 82%, followed by 68% for pre-lymphoepithelial and lymphoepithelial lesions, 63% for plasma cell shift, and 24% for germinal centers. Although FS ≥1 showed the highest sensitivity for patients with pSS (82%), specificity was higher for the other three features (98%-100%). The presence of two or more (of four) histopathological features had almost comparable sensitivity to FS alone, but specificity increased with 12% to 100%. For fulfillment of American College of Rheumatology/EULAR criteria, specificity increased from 84% to 95% when an abnormal biopsy was defined by the presence of two or more histopathological features instead of FS ≥1 only. CONCLUSION: The diagnostic accuracy of the labial gland biopsy increases when other histopathological features besides FS are taken into account, by reducing the number of false-positive biopsies.

Can ultrasound of the major salivary glands differentiate Sjögren's disease from its major mimics?

OBJECTIVES: Ultrasound of the major salivary glands (SGUS) is widely used to assess the major salivary glands in Sjögren's disease (SjD). Little is known, however, regarding the diagnostic accuracy of SGUS to differentiate SjD from its mimics. This study aims to investigate the diagnostic accuracy of SGUS in differentiating SjD from other diseases with salivary gland involvement. METHODS: SGUS was performed in 20 consecutive patients with SjD and 20 consecutive patients with well-established systemic disease, i.e., with either sarcoidosis, amyloidosis, HIV infection or chronic HCV infection. Images were scored independently by two blinded observers using the Hocevar scoring system. Diagnostic accuracy to discriminate between the patient (sub-)groups was explored. RESULTS: The accuracy of SGUS to differentiate SjD from other systemic diseases was excellent (area under ROC curve of 0.91). The optimal cut-off value to define positive or negative ultrasound for SS was 15. Sensitivity, specificity, positive predictive value and negative predictive value were high, varying from 85-90%, and diagnostic odds ratio was 51. SGUS was positive in the vast majority of SjD patients (n=18), but also in 2 patients with HIV infection and one patient with sarcoidosis. SGUS score differed significantly between patients with SjD and other systemic diseases (median 27 vs. 10, p<0.001) as well as between SjD patients and patients with either sarcoidosis, amyloidosis, HIV or HCV infection (all p<0.05). CONCLUSIONS: This study indicates that SGUS has a potentially high diagnostic accuracy to discriminate SjD from systemic diseases which can also cause salivary gland involvement.

Patient Acceptable Symptom State (PASS) in patients with primary Sjögren's syndrome in daily clinical practice.

OBJECTIVES: To explore Patient Acceptable Symptom State (PASS) in a standard of care cohort of patients with primary Sjögren's syndrome (pSS) and to compare patient characteristics including EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) between PASS and non-PASS groups. METHODS: All pSS patients fulfilling ACR/EULAR classification criteria from the Registry of Sjögren's Syndrome LongiTudinal (RESULT) cohort, who had available PASS data at baseline were included. Patient-reported outcomes included the PASS question: "Considering all the different ways your disease is affecting you, if you were to stay in this state for the next few months, do you consider your current state satisfactory?"; yes: PASS / no: non-PASS. RESULTS: Of the 278 included pSS patients, 199 (72%) had an acceptable symptom state according to the PASS question, and median ESSPRI was 6 (IQR 4-7). In the PASS group, 118 (59%) patients had an unacceptable symptom state according to ESSPRI (score ≥5). In multivariable regression analyses, ESSPRI and disease duration were independently associated with presence of PASS. The accuracy of ESSPRI to predict PASS was fair (AUC of 0.78). The cut-off point of ESSPRI for presence of PASS with the highest Youden's index was 7.2 (sensitivity 85%, specificity 56%), followed by 5.2 (sensitivity 48%, specificity 90%). CONCLUSIONS: The majority of pSS patients reported being in an acceptable symptom state according to the PASS question, despite high ESSPRI scores. In our standard of care cohort, the optimal cut-off point of ESSPRI to predict PASS is different when focusing on sensitivity (±7) or specificity (±5).

Long-term abatacept treatment for 48 weeks in patients with primary Sjögren's syndrome: The open-label extension phase of the ASAP-III trial.

OBJECTIVE: To investigate treatment efficacy of long-term abatacept treatment in pSS patients. METHODS: The single-centre ASAP-III trial consisted of two phases: the randomised, double-blind, placebo-controlled phase (1:1 randomisation) from baseline to week 24, of which results have been published previously, and the open-label extension phase from week 24 to 48, in which all patients received abatacept. Main inclusion criteria were fulfilment of the AECG criteria, positive gland biopsy, disease duration ≤ 7 years and ESSDAI ≥ 5. Long-term treatment effects of abatacept on clinical, patient-reported, glandular and laboratory outcome measures were assessed in patients treated with abatacept from baseline to week 48. Furthermore, Composite of Relevant Endpoints for Sjögren's Syndrome (CRESS) response (response on ≥3 of 5 items) was analysed. RESULTS: In patients on abatacept treatment for 48 weeks (n = 40), median ESSDAI improved from baseline 14.0 (IQR 9.0-16.8) to 4.0 (2.0-8.0) at week 48 (p < 0.001), with 50% of patients reaching low disease activity (ESSDAI < 5) at week 48. Median ESSPRI improved from 7.0 (IQR 5.4-7.7) to 5.0 (3.7-6.7) (p < 0.001). Significant improvement was also seen in dry eye and laboratory tests. Combining response at multiple clinically relevant items, 73% of patients were CRESS responders at week 48. Additional improvement was seen between week 24 and week 48 of abatacept treatment. CONCLUSION: In the open-label extension phase of the ASAP-III trial, improvement was seen up to 48 weeks of abatacept treatment in clinical, patient-reported, dry eye and laboratory outcomes. The majority of patients were CRESS responders at week 48.

Histopathology, salivary flow and ultrasonography of the parotid gland: three complementary measurements in primary Sjögren's syndrome.

OBJECTIVE: The involvement of salivary glands in primary SS (pSS) can be assessed in different ways: histopathology, salivary flow and ultrasonography. To understand the relative value of these different approaches, it is crucial to understand the relationship between them. As we routinely perform these three modalities in the parotid gland for disease evaluation, our aim was to investigate the construct validity between these modalities in one and the same gland. METHODS: Consecutive sicca patients underwent a multidisciplinary diagnostic workup including parotid gland biopsy, collection of parotid gland-specific saliva and parotid gland ultrasonography. Patients who were classified as pSS according to the ACR-EULAR criteria were included. Construct validity was assessed using Spearman's correlation coefficients. RESULTS: The 41 included pSS patients completed a full workup within a mean time interval of 2.6 months. Correlations between histopathological features and stimulated parotid salivary flow were fair (ρ = -0.123 for focus score and ρ = -0.259 for percentage of CD45+ infiltrate). Likewise, poor correlations were observed between stimulated parotid salivary flow and parotid ultrasonography (ρ = -0.196). Moderate to good associations were found between the histopathological items focus score and the percentage of CD45+ infiltrate, with parotid US scores (total US score: ρ = 0.510 and ρ = 0.560; highest for homogeneity: ρ = 0.574 and ρ = 0.633). CONCLUSION: Although pSS-associated ultrasonographic findings did correlate with histopathological features, the three modalities that evaluate salivary gland involvement assess different (or at best partly related) constructs. Therefore histopathology, salivary flow and ultrasonography are complementary measurements and cannot directly replace each other in the workup of pSS.

Clinical determinants of vaginal dryness in patients with primary Sjögren's syndrome.

OBJECTIVES: The majority of women with primary Sjögren's syndrome (pSS) suffer from vaginal dryness, which negatively impacts daily and sexual activities. As little is known about the aetiology and clinical context of this complaint, this study investigated the relationship between vaginal dryness and other clinical parameters associated with pSS. METHODS: Female participants of the REgistry of Sjögren syndrome at UMCG - LongiTudinal (RESULT) cohort who fulfilled ACR-EULAR and/or AECG classification criteria for pSS were included, using baseline data for analyses. Patient-reported vaginal dryness (range 0-10) was correlated with demographic characteristics, systemic disease activity (i.e., ESSDAI), Sjögren's Syndrome Disease Damage Index, salivary and lacrimal gland function, patient-reported outcomes (ESSPRI, MFI), serology and quality of life (SF-36, EQ-5D). Significantly associated parameters (p<0.05) were corrected for potential confounders. RESULTS: This cross-sectional study included 199 women with pSS; mean age was 52±14 years, 53% were postmenopausal, and median vaginal dryness score was 5 (IQR 2-7). Vaginal dryness was significantly associated with older age, postmenopausal status, peripheral neuropathy, oral and ocular dryness, ESSPRI and SF-36 mental and general health. After correction for age, menopausal status and medication use, peripheral neuropathy (B=1.632), oral dryness (B=0.302), and ocular dryness (B=0.230) were independently associated with vaginal dryness. CONCLUSIONS: The independent association of vaginal dryness with oral and ocular dryness might imply that the aetiology of these symptoms is partly shared. Of all extraglandular features, only peripheral neuropathy was independently associated with vaginal dryness, suggesting that peripheral neuropathy plays a significant role in the pathology of vaginal dryness in pSS.

Clinical Phenotyping of Primary Sjögren Syndrome Patients Using Salivary Gland Ultrasonography: Data From the RESULT Cohort.

OBJECTIVE: To investigate salivary gland ultrasound (SGUS) abnormalities in relation to clinical phenotype and patient characteristics, disease activity, and disease damage in patients with primary Sjögren syndrome (pSS). METHODS: Consecutive outpatients included in our REgistry of Sjögren Syndrome LongiTudinal (RESULT) cohort were selected. Patients with pSS who were included were classified according to the American College of Rheumatology/European League Against Rheumatism (EULAR) criteria and underwent full ultrasonographic examination (Hocevar score 0-48) at baseline. Total SGUS scores of ≥ 15 were considered positive. Patient characteristics, disease activity, and disease damage were compared between the different SGUS groups. RESULTS: In total, 172 of 186 patients with pSS were eligible, of whom 136 (79%) were SGUS positive. Compared with patients who were SGUS negative, SGUS-positive patients had significantly longer disease duration, higher EULAR Sjögren Syndrome Disease Activity Index, higher Sjögren Syndrome Disease Damage Index, and were more likely to have a positive parotid gland biopsy, anti-SSA/SSB antibodies, and abnormal unstimulated whole saliva (UWS) and ocular staining score (OSS), and higher levels of IgG and rheumatoid factor. Regarding patient-reported outcome measurements (PROM), patients who were SGUS positive scored significantly lower on the EULAR Sjögren Syndrome Patient-Reported Index for fatigue and pain, and more often found their disease state acceptable compared with patients who were SGUS negative. SGUS total score showed significant associations with various clinical and serological variables, and with PROM. Highest associations were found for UWS (ρ = -0.551) and OSS (ρ = 0.532). CONCLUSION: Patients who were SGUS positive show a distinct clinical phenotype in all aspects of the disease compared with patients who were SGUS negative: clinical, functional, serological, and PROM. SGUS could be a helpful tool in selecting patients for clinical trials and estimating treatment need.

Composite of Relevant Endpoints for Sjögren's Syndrome (CRESS): development and validation of a novel outcome measure.

BACKGROUND: Recent randomised controlled trials (RCTs) in primary Sjögren's syndrome used the European League Against Rheumatism (EULAR) Sjögren's Syndrome Disease Activity Index (ESSDAI) as their primary endpoint. Given the heterogeneous and complex nature of primary Sjögren's syndrome, it might be more appropriate to also assess other clinically relevant disease features. We aimed to develop a novel composite endpoint for assessing treatment efficacy in patients with primary Sjögren's syndrome: the Composite of Relevant Endpoints for Sjögren's Syndrome (CRESS). METHODS: A multidisciplinary expert team selected clinically relevant items and candidate measurements for inclusion in the composite score. For each measurement, cutoff points for response to treatment were chosen based on expert opinion, previously published data on minimal clinically important improvements, and trial data, primarily the week-24 data of the single-centre ASAP-III trial of abatacept versus placebo. CRESS was validated using data from three independent RCTs: one trial of rituximab (TRACTISS), one of abatacept (multinational trial), and one of tocilizumab (ETAP). We calculated the number and percentage of patients who were responders in the separate CRESS items, and the percentage of responders based on the total CRESS at the primary endpoint visits (week 48 for TRACTISS, week 24 for the other two trials). Patients with fewer than three items available for evaluating CRESS response were imputed as non-responders. FINDINGS: Based on expert opinion, five complementary items were selected to assess response: (1) systemic disease activity by Clinical ESSDAI (less than 5 points); (2) patient-reported symptoms by EULAR Sjögren's Syndrome Patient Reported Index, assessed by a decrease of at least 1 point or at least 15% from baseline; (3) tear gland item by Schirmer's test and ocular staining score, assessed by an increase of at least 5 mm or decrease of at least 2 points, respectively, in patients with abnormal Schirmer's test or ocular staining score findings at baseline, or, in patients with normal baseline values, assessed by no change to abnormal for both; (4) salivary gland item, assessed by unstimulated whole saliva secretion (increase of at least 25%) and salivary gland ultrasonography (decrease of at least 25%); and (5) serology, assessed by rheumatoid factor (decrease of at least 25%) and IgG (decrease of at least 10%). Total CRESS response is defined as response on at least three of five items. Post-hoc assessment of phase 3 trial data showed that CRESS response rates at the primary endpoint visits were 60% (24 of 40) for abatacept versus 18% (seven of 39) for placebo (p<0·0001) in ASAP-III, 49% (33 of 67) for rituximab versus 30% (20 of 66) for placebo (p=0·026) in the TRACTISS trial, 45% (41 of 92) for abatacept versus 32% (30 of 95) for placebo (p=0·067) in the multinational abatacept trial, and 18% (10 of 55) for tocilizumab versus 24% (13 of 55) for placebo (p=0·48) in the ETAP trial. INTERPRETATION: The CRESS is a feasible, well-balanced, composite endpoint for use in trials of primary Sjögren's syndrome. As a next step, the CRESS will require validation in a prospective RCT. FUNDING: None. TRANSLATION: For the Dutch translation of the abstract see Supplementary Materials section.

Ten years of the ESSDAI: is it fit for purpose?

Primary Sjögren's syndrome (pSS) is a very heterogeneous disease with systemic manifestations such as arthritis, skin, lung and renal involvement. To be able to assess systemic disease activity, the EULAR Sjögren's syndrome disease activity index (ESSDAI) was developed for use in daily clinical practice and in clinical trials. Since its development it has been widely used in cohort studies and clinical trials. The ESSDAI gives a systematic overview of a patient's systemic disease activity, which is very useful in daily clinical practice. However, using the ESSDAI as outcome measure in trials has been more challenging. Several RCTs with the ESSDAI as primary endpoint failed and showed large 'response rates' in placebo-treated patients as well. In this review, we discuss what we learned from using the ESSDAI in cohorts and clinical trials. We recommend to use the ESSDAI only in combination with other important outcome measures, such as patient-reported symptoms and glandular function as part of a composite endpoint in clinical trials in pSS patients.

Vaginal dryness in primary Sjögren's syndrome: a histopathological case-control study.

OBJECTIVE: The aim was to study clinical, histopathological and immunological changes in the vagina and cervix of women with primary SS, which might explain vaginal dryness. METHODS: We included 10 pre-menopausal female primary SS patients with vaginal dryness and 10 pre-menopausal controls undergoing a laparoscopic procedure. The vaginal health index was recorded. Multiplex immunoassays and flow cytometry were performed on endocervical swab and cervicovaginal lavage samples to evaluate cellular and soluble immune markers. Mid-vaginal and endocervical biopsies were taken and stained for various leucocyte markers, caldesmon (smooth muscle cells), avian V-ets erythroblastosis virus E26 oncogene homologue (ERG; endothelial cells) and anti-podoplanin (lymphatic endothelium). The number of positive pixels per square micrometre was calculated. RESULTS: One patient was excluded because of Clamydia trachomatis, and two controls were excluded because of endometriosis observed during their laparoscopy. Vaginal health was impaired in primary SS. CD45+ cells were increased in vaginal biopsies of women with primary SS compared with controls. Infiltrates were predominantly located in the peri-epithelial region, and mostly consisted of CD3+ lymphocytes. In the endocervix, CD45+ infiltrates were present in patients and in controls, but a higher number of B lymphocytes was seen in primary SS. Vascular smooth muscle cells were decreased in the vagina of primary SS patients. No differences were found in leucocyte subsets in the vaginal and endocervical lumen. CXCL10 was increased in endocervical swab samples of primary SS patients. CONCLUSION: Women with primary SS show impaired vaginal health and increased lymphocytic infiltration in the vagina compared with controls. Vaginal dryness in primary SS might be caused by vascular dysfunction, possibly induced by IFN-mediated pathways.

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.

Abatacept treatment for patients with early active primary Sjögren's syndrome: a single-centre, randomised, double-blind, placebo-controlled, phase 3 trial (ASAP-III study).

BACKGROUND: Several small open-label studies have suggested efficacy of abatacept-a co-stimulation inhibitor-in patients with primary Sjögren's syndrome. These promising results warranted further evaluation. We therefore aimed to further assess the safety and efficacy of abatacept compared with placebo in patients with primary Sjögren's syndrome. METHODS: We did a single-centre, randomised, double-blind, placebo-controlled, phase 3 trial at the University Medical Center Groningen (Groningen, Netherlands). We included patients with primary Sjögren's syndrome fulfilling the American-European Consensus Group criteria, aged 18 years or older, with positive salivary gland biopsies, time from diagnosis of 7 years or less, and a European League Against Rheumatism Sjögren's Syndrome Disease Activity Index (ESSDAI) score of 5 or more. Independent pharmacists randomly allocated patients (1:1) to either the abatacept group or placebo group using a computer-generated sequence stratified by previous use of disease-modifying anti-rheumatic drugs. Patients received at-home subcutaneous injections of abatacept (125 mg) or placebo once a week for 24 weeks. The primary outcome was the between-group difference in ESSDAI score at week 24. Efficacy was analysed in patients who received at least one drug dose and for whom post-baseline data were collected. Safety was analysed in all patients who received at least one drug dose. FINDINGS: Between Aug 14, 2014, and Aug 23, 2018, 580 patients were reviewed for eligibility, of which 80 patients were randomly assigned to receive study treatment. Efficacy was analysed in 40 patients receiving abatacept and 39 patients receiving placebo (one patient in this group was lost to follow-up). The primary outcome did not significantly differ between the treatment groups. The adjusted mean difference in ESSDAI score at week 24 between the abatacept group and placebo group was -1·3 (95% CI -4·1 to 1·6). No deaths or treatment-related serious adverse events occurred. In 38 (95%) of 40 patients in the abatacept group, 103 adverse events occurred, including one serious adverse event and 46 infections. In 38 (95%) of 40 patients in the placebo group, 87 adverse events occurred, including four serious adverse events and 49 infections. INTERPRETATION: On the basis of this trial, we cannot recommend abatacept treatment as standard of care to reduce systemic disease activity in patients with primary Sjögren's syndrome. Further studies should evaluate whether patients with specific clinical manifestations and biological characteristics might benefit from abatacept treatment. FUNDING: Bristol-Myers Squibb.

Presence of intraepithelial B-lymphocytes is associated with the formation of lymphoepithelial lesions in salivary glands of primary Sjögren's syndrome patients.

OBJECTIVES: Lymphoepithelial lesions (LELs) in salivary glands are associated with primary Sjögren's syndrome (pSS). LELs are composed of hyperplastic epithelium infiltrated with lymphocytes. The objective of this study was obtaining insight in the relative roles of intraepithelial B- and T-lymphocytes in the formation of LELs in salivary glands of pSS patients. METHODS: Parotid and labial salivary gland biopsies of pSS patients (n=15), non-SS sicca patients (n=5) and non-sicca controls (n=5) were analysed. Serial sections were stained with H & E and for cytokeratin, CD20 and CD3. Striated ducts with lymphocytes, but without hyperplasia, and striated ducts with LELs were identified in H & E and cytokeratin stained sections. LELs were classified in successive stages of severity based on the amount of hyperplasia (stage1-3). Numbers of B- and T-lymphocytes within striated ducts and LELs were counted in CD20 and CD3 stained sections. RESULTS: Lymphocyte-containing striated ducts of both salivary glands of all pSS and control patients harboured T-lymphocytes, scattered throughout the ductal epithelium. In contrast, B-lymphocytes were exclusively found in a small fraction (21%) of striated ducts without hyperplasia and in nearly all striated ducts with LELs of pSS patients, but not in controls. In striated ducts with LELs B-lymphocytes were mostly located in the areas of proliferating epithelium. Numbers of B-lymphocytes and B/T-ratios increased significantly with higher severity of LELs. This was even more pronounced in the parotid than in the labial gland. CONCLUSIONS: We conclude there is an association between presence of intraepithelial B-lymphocytes and the formation of LELs in salivary glands of pSS patients.

Serum immunoglobulin free light chains are sensitive biomarkers for monitoring disease activity and treatment response in primary Sjögren's syndrome.

Objectives: Serum immunoglobulin free light chains (FLCs) are frequently elevated in B-cell-mediated autoimmune diseases, including primary SS (pSS). The objective of this study was to assess if serum FLCs can contribute to classification, mucosa-associated lymphoid tissue (MALT) lymphoma detection, monitoring of disease activity and treatment response in pSS. Methods: Serum samples of 100 consecutive patients suspected of pSS were included. Forty-five patients fulfilled ACR-EULAR criteria for pSS. Additionally, samples of 17 pSS patients with MALT lymphoma and longitudinal samples of pSS patients treated with rituximab (n = 20), placebo (n = 10) or abatacept (n = 15) were included. Serum FLCκ/FLCλ was measured by nephelometry or turbidimetry. Results: At diagnosis, FLCκ and FLCλ serum levels were significantly higher in pSS compared with non-SS sicca patients. The FLCκ/FLCλ ratio was abnormal in 11% of pSS patients. In established MALT-pSS patients, without recent rituximab treatment (n = 12), 50% had abnormal FLCκ/FLCλ ratios. FLC measurement had no additional value for pSS classification, compared with IgG and anti-SSA. FLC levels correlated significantly with systemic disease activity, assessed by EULAR SS Disease Activity Index (ESSDAI) and clinical ESSDAI, both cross-sectionally and longitudinally following treatment. Treatment with rituximab or abatacept significantly lowered FLC levels. FLCs show a large sensitivity to change and relative changes induced by treatment were higher compared with IgG. Conclusion: Serum FLCs are elevated in pSS, and abnormal FLCκ/FLCλ ratios may be indicative for the presence of MALT lymhoma. FLC levels can be used as a biomarker for systemic disease activity and monitoring treatment responses. FLCs are sensitive to change and have more favorable kinetics than IgG.

Validation of the ACR-EULAR criteria for primary Sjögren's syndrome in a Dutch prospective diagnostic cohort.

Objectives: To validate the ACR-EULAR classification criteria for primary SS (pSS), and compare them to the American-European Consensus Group (AECG) and ACR criteria in a Dutch prospective diagnostic cohort. Methods: Consecutive patients (n = 129) referred for suspicion of pSS underwent a multidisciplinary evaluation, including a labial and/or parotid gland biopsy. Patients with an incomplete work-up (n = 8) or associated systemic auto-immune disease (n = 7) were excluded. The ACR-EULAR classification was compared with expert classification, AECG and ACR classification. Additionally, the accuracy of individual ACR-EULAR items in discriminating pSS from non-pSS was evaluated. The validity of criteria sets was described separately using parotid or labial gland biopsy results for classification. Results: Of the 114 evaluated patients, the expert panel classified 34 (30%) as pSS and 80 (70%) as non-pSS. Using labial gland biopsy results, ACR-EULAR classification showed 87% absolute agreement (κ = 0.73) with expert classification, with a sensitivity of 97% and specificity of 83%. Using the parotid gland biopsy results, the ACR-EULAR criteria performed excellently as well. Focus score, anti-SSA titre and ocular staining score showed good to excellent accuracy, whereas unstimulated whole saliva and Schirmer's test had poor accuracy. The ACR-EULAR and AECG criteria had equal validity. Compared with ACR classification, ACR-EULAR classification showed higher sensitivity but lower specificity. Conclusion: The ACR-EULAR criteria showed good agreement with expert classification, but some patients may be misclassified as pSS. Unstimulated whole saliva and Schirmer's test showed poor discriminative value. The ACR-EULAR criteria performed equally to the AECG criteria, and had higher sensitivity but lower specificity than the ACR criteria.

Scoring hypoechogenic areas in one parotid and one submandibular gland increases feasibility of ultrasound in primary Sjögren's syndrome.

OBJECTIVE: To assess whether ultrasonographic scoring of (i) both parotid and submandibular salivary glands and (ii) all individual components of the Hocevar scoring system, is needed for classifying patients as primary Sjögren's syndrome (pSS). METHODS: Ultrasound examination of the major salivary glands (sUS) was performed in 204 consecutive patients clinically suspected (n=171) or diagnosed (n=33) with pSS.Parenchymal echogenicity, homogeneity, hypoechogenic areas, hyperechogenic reflections and salivary gland posterior border were scored in left and right parotid and submandibular glands. Logistic regression analyses were performed to assess which glands and sUS components contributed significantly to classification as pSS or non-pSS according to the 2016 American College of Rheumatology-European League Against Rheumatism (ACR-EULAR) criteria. RESULTS: 116 (57%) patients were classified as pSS, the remaining as non-pSS. Instead of scoring both sides (area under the curve; AUC=0.856, Nagelkerke R2=0.526), multivariate analysis showed that sUS scoring of only right (AUC=0.850; R2=0.518) or left (AUC=0.852; R2=0.511) parotid and submandibular glands is sufficient to predict ACR-EULAR classification. Moreover, all individual components of the Hocevar scoring system significantly predicted classification. Multivariate analysis showed that parenchymal echogenicity and hypoechogenic areas contributed independently to ACR-EULAR classification (AUC=0.857; R2=0.539). Scoring these components in one parotid and one submandibular gland highly predicted ACR-EULAR classification (AUC=0.855; R2=0.539). Scoring only hypoechogenic areas on one side showed almost similar results (AUC=0.846; R2=0.498). CONCLUSION: sUS examination of parotid and submandibular glands on one side is sufficient to predict classification of patients according to the ACR-EULAR criteria. To further increase feasibility of sUS in outpatient clinics worldwide, only hypoechogenic areas can be scored.

Ultrasound of the Major Salivary Glands is a Reliable Imaging Technique in Patients with Clinically Suspected Primary Sjögren's Syndrome.

OBJECTIVE: To assess the inter- and intraobserver reliability of ultrasound of major salivary glands in patients clinically suspected of having primary Sjögren's syndrome (pSS) as well as to assess sources of variation in outcomes of ultrasonographic evaluation. METHODS: 80 consecutive outpatients with clinically suspected pSS underwent ultrasound evaluation. The following ultrasound variables of the parotid and submandibular salivary glands were assessed: echogenicity, parenchymal homogeneity, presence of hypoechogenic areas, hyperechogenic reflections and clearness of posterior glandular border, according to the scoring system of Hocevar et al. (total score range: 0 - 48). Images were scored independently by three blinded observers in two sessions. RESULTS: The intraobserver reliability of the total ultrasound score was excellent, with an intraclass correlation (ICC) ranging from 0.89 to 0.96. The interobserver reliability was good to excellent, with ICCs of 0.84 and 0.76 for the total ultrasound score in the two sessions. The kappa value ranged from 0.60 to 0.83 depending on the applied cut-offs (cut-off score ≥ 15 and ≥ 17). Hypoechogenic areas and homogeneity of parotid glands showed the highest interobserver reliability. The median kappa for echogenicity was low. The total ultrasound scores varied more between observers in patients with higher ultrasonographic scores (approximately scores ≥ 20). CONCLUSION: Ultrasound of major salivary glands is a reliable imaging technique for patients with clinically suspected pSS. Discrepancies between observers in assessing the severity of ultrasound findings may interfere with detecting 'true' changes over time. When monitoring the progression of pSS or treatment efficacy, it is advised that a particular patient be scored by the same ultrasonographer at every time point.