Clinical characteristics and biopsy accuracy in suspected cases of Sjögren's syndrome referred to labial salivary gland biopsy

British Society for Rheumatology guideline on management of adult and juvenile onset Sjögren disease

Sjögren disease (SD) is a chronic, autoimmune disease of unknown aetiology with significant impact on quality of life. Although dryness (sicca) of the eyes and mouth are the classically described features, dryness of other mucosal surfaces and systemic manifestations are common. The key management aim should be to empower the individual to manage their condition-conserving, replacing and stimulating secretions; and preventing damage and suppressing systemic disease activity. This guideline builds on and widens the recommendations developed for the first guideline published in 2017. We have included advice on the management of children and adolescents where appropriate to provide a comprehensive guideline for UK-based rheumatology teams.

Serology and histology in Sjögren's syndrome diagnosis: a retrospective accuracy study

INTRODUCTION

Sjögren's syndrome (SS) presents complex diagnostic challenges due to its multi-organ involvement, often leading to misdiagnosis, which can result in unnecessary treatments, elevated healthcare costs, and significant impacts on patient quality of life. Accurate diagnosis is therefore critical, utilising ACR/EULAR criteria that include both labial minor salivary gland (LMSG) biopsy and anti-SSA antibodies.

METHODS

This retrospective study analysed medical records of 87 adults suspected of primary SS, who underwent both anti-SSA serology and LMSG biopsy. We evaluated the diagnostic accuracy of these tests under existing ACR/EULAR criteria and a newly proposed 'modified ACR/EULAR criteria - ClinDx'. Statistical analysis included Pearson's chi-square test for the association between test results and disease status and receiver operating characteristic (ROC) curves to assess the sensitivity and specificity of the diagnostic models.

RESULTS

Utilising ACR/EULAR criteria, 40 patients were diagnosed with SS, while 47 were categorised as non-diseased. The ClinDx criteria application resulted in 32 SS diagnoses and 55 non-diseased classifications, highlighting discrepancies in patients with low anti-SSA titers (< 200 MFU). Statistical analysis confirmed a significant association (p < 0.001) between test results and disease status, indicating the robustness of the modified criteria in enhancing diagnostic accuracy.

CONCLUSIONS

This study underscores the utility of integrating serological tests and histological biopsies in diagnosing SS. While anti-SSA antibodies provide a good preliminary screening tool, the specificity of LMSG biopsies is indispensable. Refining both serological and histological assessments per ClinDx criteria can improve diagnostic accuracy, aiding in better management of SS and reducing healthcare burdens.

Salivary Flow Rate in Patients with Sjögren's Syndrome: Correlations with Salivary Gland Ultrasound Findings and Biomarkers of Disease Activity

Sjögren's syndrome (SS) is a slowly progressive, chronic autoimmune inflammatory condition characterized by the affliction of the exocrine glands, with issues that derive from it markedly decreasing the quality of life of these patients. Salivary gland involvement can be identified through imaging methods. Among them, salivary gland ultrasonography (SGUS) is used as a diagnostic and prognostic tool in pSS. The aim of the present study was to assess the salivary flow rate and correlations between it and SGUS findings and markers of pSS activity. A total of 112 patients with pSS and 56 healthy subjects were included in this study. All patients underwent investigations including the measurement of serum autoantibodies, salivary flow rate determination, and ultrasonographic evaluation. SGUS modifications had a strong inverse correlation with salivary flow (r = -68.002, p < 0.0001) and a positive, strong correlation with IL-6 and Beta-2-microglobulin (r = -0.78 and r = -0.84, respectively, p < 0.001 in both cases). The SGUS findings were also strongly and positively correlated with the ESSDAI (r = -0.88, p < 0.0001) and Focus scores (r = -0.82, p < 0.0001). SGUS represents a non-invasive means of assessing the state of the salivary glands and, implicitly, the salivary flow of patients, offering valuable insights into disease progression and steps that can be taken in order to improve patients' quality of life.

Pulmonary Involvement in Sjögren's Syndrome: Correlations with Biomarkers of Activity and High-Resolution Computer Tomography Findings

(1) Background: Sjögren's syndrome (SS) represents a systemic autoimmune disease whose pathophysiology has yet to be elucidated, though it is known that the inflammatory process encountered in SS is of a systemic nature, with cytokines representing the main mediators for tissue damage. (2) Aim of the study: The aim of the present study is to further the understanding of the link between interleukin serum levels, cytokine serum levels, HRCT findings and the Warrick score (as tools for the evaluation of pulmonary involvement) in patients with pSS. (3) Methods: The present study is a retrospective, observational one aimed at ascertaining the link between SS activity and its clinical implications, as well as how interleukin and TNF-α levels correlate with systemic changes. The study enrolled 112 patients with pSS and 56 healthy subjects, matched for age and gender, as a control group. pSS activity was assessed using the ESSDAI. Cytokine levels and leukocyte and lymphocyte counts were measured in both groups. The focus score was calculated for each patient, HRCT was performed to assess lung function, and the Warrick score was calculated. (4) Conclusions: HRCT revealed NSIP in 13 patients (59.09%) and UIP in 9 patients. The strongest positive correlation was identified upon analyzing the relation between IL-8 and the Warrick score (r = 0.9156, p < 0.00001), followed by a positive correlation between the score and IL-6 levels (r = 0.5738, p < 0.0052). Unsurprisingly, the degree and severity of pulmonary involvement was also positively correlated with the degree of disease activity (r = 0.4345, p = 0.0433).

Endothelial Dysfunction in Primary Sjögren's Syndrome: Correlation with Serum Biomarkers of Disease Activity

To assess the relationship between endothelial dysfunction and serum cytokines, anti-SSA and anti-SSB antibodies, beta-2 microglobulin levels, focus score and EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) in primary Sjögren's syndrome (pSS) patients. The study included 90 patients with pSS and 45 healthy subjects, matched for age and gender, as controls. Serum beta-2 microglobulin, total cholesterol, HDL-cholesterol, triglycerides, TNF-α, and IL-6 were analyzed in both the groups. Patients with pSS were also tested for antinuclear antibodies, anti-SAA (anti-Sjögren's syndrome-related antigen A) antibodies, anti-SSB (anti-Sjögren syndrome related antigen B) antibodies, and focus score (the histopathologic one, based on minor salivary gland biopsy). Endothelial dysfunction was assessed by means of flow-mediated dilation (FMD) in the brachial artery. Data are presented as mean ± standard deviation. Statistical analysis was performed using the t-test and the Pearson's correlation. Differences were considered to be statistically significant if the value of p < 0.05. Endothelial dysfunction was identified in pSS patients (p < 0.00001). The serum levels of cytokines (TNF-α, respective IL-6) and beta-2 microglobulin were increased in pSS patients compared with controls (p < 0.00001). Endothelial dysfunction (expressed as FMD%) was correlated with focus score, ESSDAI, levels of anti-SSA and anti-SSB antibodies, beta-2 microglobulin, IL-6, and TNF-α, with statistical significance. Endothelial dysfunction is present in pSS patients and is associated with a high focus score and activity as well as increased concentrations of antibodies, pro-inflammatory cytokines, and beta 2-microglobulin.

Identification of Salivary Metabolic Signatures Associated with Primary Sjögren's Disease

Sjögren's disease (SjD) is the second most prevalent autoimmune disorder that involves chronic inflammation of exocrine glands. Correct diagnosis of primary SjD (pSjD) can span over many years since disease symptoms manifest only in advanced stages of salivary and lachrymal glandular destruction, and consensus diagnostic methods have critical sensitivity and selectivity limitations. Using nuclear magnetic resonance (NMR) spectroscopy, we determined the composition of metabolites in unstimulated saliva samples from 30 pSjD subjects and 30 participants who do not have Sjögren's disease (non-Sjögren's control group, NS-C). Thirty-four metabolites were quantified in each sample, and analysis was conducted on both non-normalized (concentration) and normalized metabolomics data from all study participants (ages 23-78) and on an age-restricted subset of the data (ages 30-70) while applying false discovery rate correction in determining data significance. The normalized data of saliva samples from all study participants, and of the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate, as well as significant decreases in the levels of 5-aminopentanoate, acetate, butyrate and propionate, in subjects with pSjD compared to subjects in the NS-C group. Additionally, a significant increase in choline was found only in the age-restricted subset, and a significant decrease in fucose was found only in the whole study population in normalized data of saliva samples from the pSjD group compared to the NS-C group. Metabolite concentration data of saliva samples from all study participants, but not from the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate in subjects with pSjD compared to controls. The study showed that NMR metabolomics can be implemented in defining salivary metabolic signatures that are associated with disease status, and can contribute to differential analysis between subjects with pSjD and those who are not affected with this disease, in the clinic.

Neurologic involvement in seronegative primary Sjögren's syndrome with positive minor salivary gland biopsy: a single-center experience

Objective

To assess the demographics, neurologic manifestations, comorbidities, and treatment of patients with seronegative primary Sjögren's syndrome (pSS).

Patients and methods

We conducted a retrospective chart review on patients with seronegative pSS evaluated by a neurologist at the University of Utah Health between January 2010 and October 2018. The diagnosis was based on characteristic symptoms, positive minor salivary gland biopsy according to the American-European Consensus Group 2002 criteria, and seronegative antibody status.

Results

Of 45 patients who met the study criteria, 42 (93.3%) were Caucasian, and 38 (84.4%) were female. The patients' mean age at diagnosis was 47.8 ± 12.6 (range 13-71) years. Paresthesia, numbness and dizziness, and headache were noted in 40 (88.9%), 39 (86.7%), and 36 patients (80.0%), respectively. Thirty-four patients underwent brain magnetic resonance imaging. Of these, 18 (52.9%) showed scattered nonspecific periventricular and subcortical cerebral white matter T2/fluid-attenuated inversion recovery hyperintense foci. Twenty-nine patients (64.4%) presented to the neurology clinic prior to pSS diagnosis, and the median delay in diagnosis from the first neurology clinic visit was 5 (interquartile ranges 2.0-20.5) months. Migraine and depression were the most common comorbidities in 31 patients (68.9%). Thirty-six patients received at least one immunotherapy, and 39 were on at least one medication for neuropathic pain.

Conclusion

Patients often display various nonspecific neurological symptoms. Clinicians should express a high degree of skepticism regarding seronegative pSS and consider minor salivary gland biopsy to avoid delaying diagnosis, as undertreatment can affect patients' quality of life.

A combination treatment of low-dose dexamethasone and aspirin-triggered resolvin D1 reduces Sjögren syndrome-like features in a mouse model

Background

Sjögren syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration and diminished secretory function of the salivary glands. Dexamethasone (DEX) resolves dry mouth and lymphocytic infiltration; however, this treatment is difficult to maintain because of multiple adverse effects (eg, osteoporosis and skin thinning); likewise, aspirin-triggered resolvin D1 (AT-RvD1) increases saliva secretion but cannot eliminate lymphocytic infiltration. Previous studies showed that a combination of low-dose DEX with AT-RvD1 before disease onset prevents SS-like features in a mouse model; however, this is not clinically practical because there are no reliable indicators of SS before disease onset. Therefore, the authors applied the combined treatment at disease onset to show its efficacy and comparative lack of adverse effects, so that it may reasonably be maintained over a patient's lifetime.

Methods

NOD/ShiLtJ mice were treated with ethanol (vehicle control), high-dose DEX alone, AT-RvD1 alone, or a combination of low-dose DEX with AT-RvD1 at disease onset for 8 weeks. Then saliva flow rates were measured, and submandibular glands were harvested for histologic analyses.

Results

A combined treatment of low-dose DEX with AT-RvD1 significantly decreased mast cell degranulation and lymphocytic infiltration, increased saliva secretion, and restored apical aquaporin-5 expression in submandibular glands of NOD/ShiLtJ mice.

Conclusions

Low-dose DEX combined with AT-RvD1 reduces the severity of SS-like manifestation and prevents the development of advanced and potentially irreversible damage, all in a form that can reasonably be administered indefinitely without the need to cease treatment because of secondary effects.

Exosome-Derived microRNAs from Mouthrinse Have the Potential to Be Novel Biomarkers for Sjögren Syndrome

Sjögren syndrome (SS) is diagnosed based on invasive tissue biopsies and blood sampling. Therefore, a novel non-invasive and simple inspection diagnostic marker of SS is required. Here, we identified exosome-derived microRNAs (miRNAs) as biomarkers for SS using non-invasive mouthrinse samples collected from patients with SS and healthy volunteers. We compared miRNAs derived from exosomes in mouthrinse samples from the two groups using microarrays and real-time polymerase chain reaction (PCR) and identified 12 miRNAs as biomarker candidates. The expression ratios of four miRNAs were significantly increased in the SS group compared to the control group. Logistic regression analysis revealed a more significant influence of miR-1290 and let-7b-5p in the SS group than that in the control group. We combined these miRNAs to create a diagnostic prediction formula using logistic regression analysis. The combination of miR-1290 and let-7b-5p distinguished SS from the control samples with an AUC, sensitivity, specificity, positive predictive value, and negative predictive value of 0.856, 91.7%, 83.3%, 84.6%, and 90.9%, respectively. These results indicated that an increased ratio of these miRNAs could serve as a novel and non-invasive diagnostic marker for SS. This is the first report of diagnosis and screening of SS by adopting a non-invasive method using mouthrinse.

Minor Salivary Gland Biopsy in Diagnosis of Sjögren’s Syndrome

Objective

Previous studies have questioned the safety and efficacy of minor salivary gland biopsy in the diagnosis of Sjögren’s syndrome, citing complications and difficulty of pathologic evaluation. This study aims to determine the rate of biopsy specimen adequacy and the risk of complications after minor salivary gland biopsy.

Study Design

Case series.

Setting

Single tertiary care center.

Methods

We reviewed the records of all patients who underwent minor salivary gland biopsy at our institution from October 1, 2016, to September 1, 2021. Demographics, comorbidities, symptoms, and serologic results were recorded. The primary outcome was adequacy of the tissue sample. Complications of the procedure were recorded. Biopsies with at least one focus of ≥50 lymphocytes per 4-mm2 sample were considered positive.

Results

We identified 110 patients who underwent minor salivary gland biopsy. Ninety-three (85%) were female, and the median age was 49.1 years (range, 18.7-80.5). Seventy-seven procedures (70%) were performed in the office setting, and 33 (30%) were performed in the operating room. Nearly all biopsy samples (n = 108, 98%) were adequate, and 33 (31%) were interpreted as positive. Four patients (4%) experienced temporary lip numbness, which resolved with conservative management. No permanent complications were reported after lip biopsy. Nineteen (58%) patients with positive biopsy results had no Sjögren’s-specific antibodies. Most patients with positive biopsy results (n = 20, 61%) subsequently started immunomodulatory therapy.

Conclusion

Minor salivary gland biopsy can be performed safely and effectively in both the office and the operating room. This procedure provides clinically meaningful information and can be reasonably recommended in patients suspected to have Sjögren’s syndrome.

Research on primary Sjögren's syndrome in 2004-2021: a Web of Science-based cross-sectional bibliometric analysis

The extent, range, and nature of available research in the field of primary Sjögren's syndrome (pSS) have not been understood fully. This study aimed to map the literature available on pSS, and identify global hotspots and trends in the research. Papers on pSS published between 2004 and 2021 were searched from Web of Science Core Collection. The quantity and citations of publications, and the research hotspots and trends in the field of pSS were analyzed and presented visually by Microsoft Excel and Citespace software. A total of 3606 papers mainly from 526 institutions in 83 countries/regions were included for analysis. The number of publications presented an overall upward trend in the field of pSS from 2004 to 2021. The USA ranked first in the number of publications (n = 661), followed by China (n = 491), Italy (n = 405), France (n = 351), and Japan (n = 292). Moreover, seven of the top ten countries by the number of publications on pSS were from Europe. The University of Groningen (n = 661), Xavier Mariette (n = 95), and Clinical and Experimental Rheumatology (n = 184) were the most prolific affiliation, author, and journal, respectively. Vitali C (n = 2009) and Arthritis and Rheumatism (n = 3918) held the record for the most cited papers by an author and journal, respectively. At present, the hot keywords in the field of pSS include disease activity, ultrasonography, management, consensus, and data-driven. Lymphoid organization, clinical phenotypes outcome, salivary gland ultrasonography, and Toll-like receptor are the emerging research trends in pSS. Research on pSS is flourishing. Current research of pSS mainly focuses on disease activity, ultrasonography, and management. While, the emerging research trends in pSS are lymphoid organization, clinical phenotypes outcome, salivary gland ultrasonography, and Toll-like receptor.

Sclerosing Sialadenitis Is Associated With Salivary Gland Hypofunction and a Unique Gene Expression Profile in Sjögren's Syndrome

Purpose

To develop a novel method to quantify the amount of fibrosis in the salivary gland and to investigate the relationship between fibrosis and specific symptoms associated with Sjögren’s syndrome (SS) using this method.

Materials and Methods

Paraffin-embedded labial salivary gland (LSG) slides from 20 female SS patients and their clinical and LSG pathology data were obtained from the Sjögren’s International Collaborative Clinical Alliance. Relative interstitial fibrosis area (RIFA) in Masson’s trichrome-stained LSG sections was quantified from digitally scanned slides and used for correlation analysis. Gene expression levels were assessed by microarray analysis. Core promoter accessibility for RIFA-correlated genes was determined using DNase I hypersensitive sites sequencing analysis.

Results

RIFA was significantly correlated with unstimulated whole saliva flow rate in SS patients. Sixteen genes were significantly and positively correlated with RIFA. In a separate analysis, a group of differentially expressed genes was identified by comparing severe and moderate fibrosis groups. This combined set of genes was distinct from differentially expressed genes identified in lung epithelium from idiopathic pulmonary fibrosis patients compared with controls. Single-cell RNA sequencing analysis of salivary glands suggested most of the RIFA-correlated genes are expressed by fibroblasts in the gland and are in a permissive chromatin state.

Conclusion

RIFA quantification is a novel method for assessing interstitial fibrosis and the impact of fibrosis on SS symptoms. Loss of gland function may be associated with salivary gland fibrosis, which is likely to be driven by a unique set of genes that are mainly expressed by fibroblasts.

Adverse post-operative events of salivary gland biopsies: A systematic review and meta-analysis

OBJECTIVES

The study aimed to perform a systematic review and meta-analysis of the complications following major and minor salivary gland biopsy.

MATERIALS AND METHODS

Observational studies assessing postoperative complications of minor salivary gland biopsy and indexed at Medline/PubMed, EMBASE, Cinahl, LILACS, or Scopus were selected. This review was registered under the protocol number: CRD42020211169. The level of significance considered was 0.05, and the R software (The R Foundation) was used for the meta-analysis.

RESULTS

Twenty-seven studies reporting 3208 patients were included in this review. The combined prevalence of postsurgical complications was 11% (95% CI, 8 to 13%, p = 0.01). The percentage of the combined prevalence of neurological complications was 3% (95% CI, 1-6%, p = 0.01). The surgical technique did not influence the frequency of overall and neurological complications.

CONCLUSION

Minor salivary gland biopsies are a safe and predictable procedure that should be performed on the lower lip. Postoperative complications are more common than previously reported, but permanent complaints are uncommon.

Handheld spatial frequency domain imager for noninvasive Sjögren's syndrome labial salivary gland biopsy

A labial salivary gland biopsy (LSGB) plays an essential role in diagnosing Sjögren's syndrome (SS), but its clinical application is limited due to its invasiveness. Here, we present a handheld single snapshot multiple-frequency demodulation-spatial frequency domain imaging (SSMD-SFDI) device for a rapid optical biopsy of labial salivary glands noninvasively. The structural and physiological parameters of lower lip mucosa were obtained from the light reflectance of the layered oral mucosa. The recovered parameters were found to correlate strongly with the progression of SS. In our pilot study on 15 healthy subjects and 183 SS patients, a support vector machine (SVM) classifier using the measured parameters distinguished healthy subjects, LSGB I, II, III, and IV patients in sequence with AUCs of 0.979, 0.898, 0.906, and 0.978, respectively. Critical structural and physiological alterations in the mucosa due to SS were further identified and used to assess its risk using an explainable neural network. The handheld spatial frequency domain imager may serve as a valuable label-free and noninvasive tool for early diagnosing and surveying SS.

Diagnostic performance of serology against histologic assessment to diagnose Sjogren's syndrome: a systematic review

The objective of this review was to assess and evaluate whether the published diagnostic accuracy studies provide evidence to sustain the current diagnostic guidelines put forth by ACR/EULAR used for patients with suspected Sjögren's syndrome (SS). Literature databases, including Medline, Embase, and EBM Reviews, were searched for relevant studies on the correlation between ACR/EULAR criteria, particularly those with a direct comparison between their accuracy in diagnosing Sjögren's syndrome. We followed Cochrane, QUADAS-2, and STARD guidelines and the four-phase flow diagram by the PRISMA Statement. Reports in several languages, but only human studies were considered. Three studies assessed the accuracy of the current diagnostic tests, and these did not present adequate designs that would allow a well-supported conclusion with a high level of certainty. Due to significant clinical and methodological heterogeneity, a meta-analysis was not performed. A qualitative review of the papers was undertaken. Neither the comparative nor the non-comparative study designs permit conclusive recommendations regarding an alternative diagnostic pathway for SS. Well-designed studies of the diagnostic accuracy of SS tests are needed to validate current guidelines or to suggest changes to the current guidelines.

Vibrational Spectroscopy Saliva Profiling as Biometric Tool for Disease Diagnostics: A Systematic Literature

Saliva is a biofluid that can be considered as a "mirror" reflecting our body's health status. Vibrational spectroscopy, Raman and infrared, can provide a detailed salivary fingerprint that can be used for disease biomarker discovery. We propose a systematic literature review based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to evaluate the potential of vibrational spectroscopy to diagnose oral and general diseases using saliva as a biological specimen. Literature searches were recently conducted in May 2020 through MEDLINE-PubMed and Scopus databases, without date limitation. Finally, over a period of 10 years, 18 publications were included reporting on 10 diseases (three oral and seven general diseases), with very high diagnostic performance rates in terms of sensitivity, specificity, and accuracy. Thirteen articles were related to six different cancers of the following anatomical sites: mouth, nasopharynx, lung, esophagus, stomach, and breast. The other diseases investigated and included in this review were periodontitis, Sjögren's syndrome, diabetes, and myocardial infarction. Moreover, most articles focused on Raman spectroscopy (n = 16/18) and more specifically surface-enhanced Raman spectroscopy (n = 12/18). Interestingly, vibrational spectroscopy appears promising as a rapid, label-free, and non-invasive diagnostic salivary biometric tool. Furthermore, it could be adapted to investigate subclinical diseases-even if developmental studies are required.

Expression of NGAL-specific cells and mRNA levels correlate with inflammation in the salivary gland, and its overexpression in the saliva, of patients with primary Sjögren's syndrome

Salivary gland involvement is a characteristic feature of primary Sjögren's syndrome (pSS), where tissue destruction is mediated by infiltrating immune cells, and may be accompanied by the presence of adipose tissue. Optimally diagnosing this multifactorial disease requires the incorporation of additional routines. Screening for disease-specific biomarkers in biological fluid could be a promising approach to increase diagnostic accuracy. We have previously investigated disease biomarkers in saliva and tear fluid of pSS patients, identifying Neutrophil gelatinase-associated lipocalin (NGAL) as the most upregulated protein in pSS. In the current study, we aimed to explore for the first time NGAL expression at the site of inflammation in the pSS disease target organ. Immunohistochemical staining was conducted on minor salivary gland biopsies from 11 pSS patients and 11 non-SS sicca subjects, targeting NGAL-specific cells. Additional NGAL/PNAd double staining was performed to study NGAL expression in high endothelial venules, known as specialised vascular structures. Moreover, NGAL mRNA expression was measured utilising quantitative real-time polymerase chain reaction (qRT-PCR) on minor salivary gland biopsies from 15 pSS patients and 7 non-SS sicca individuals that served as tissue controls. Our results demonstrated NGAL expression in acinar and ductal epithelium within the salivary gland of pSS patients, where significantly greater levels of acinar NGAL were observed in pSS patients (p < .0018) when compared to non-SS subjects. Also, acinar expression positively correlated with focus score values (r ² = 0.54, p < .02), while ductal epithelial expression showed a negative such correlation (r ² = 0.74, p < .003). Some PNAD⁺ endothelial venules also expressed NGAL. An increase in NGAL staining with increased fatty replacement was also observed in pSS patients. Concurringly, a 27% increase in NGAL mRNA levels were also detected in the minor salivary glands of pSS patients when compared to non-SS tissue control subjects. In conclusion, there is a positive association between increase in NGAL expression and inflammation in the pSS disease target organ, which also coincides with its previously demonstrated upregulation in the saliva of pSS patients. Additional functional analyses are needed to better understand the immunological implications of this potential biomarker.

Epithelial Cell Adhesion Molecule in Primary Sjögren's Syndrome Patients: Characterization and Evaluation of a Potential Biomarker

Objective

To determine the subcellular localization of epithelial cell adhesion molecule (EpCAM) in labial salivary gland (LSG) and evaluate the diagnostic use of the extracellular domain of EpCAM (EpEX) and intracellular domain (EpICD) for primary Sjögren's syndrome (pSS).

Methods

Immunohistochemical (IHC) analysis was conducted using EpEX and EpICD domain-specific antibodies on labial salivary gland biopsy (LSGB) from participants. Chi-square or Fisher's exact analysis, Mann-Whitney U-test, and Kruskal-Wallis test compared differences among groups. Independent risk factors of pSS were determined by multiple logistic regression analysis. Receiver-operator characteristic curves (ROC) were carried out to estimate the diagnostic value.

Results

Compared to non-SS controls, loss of membranous EpEX and EpICD expression was observed in LSGB of pSS patients, which occurred in parallel with increased accumulation of cytoplastic and nuclear EpICD. The subcellular EpEX/EpICD expressions were associated with various features of pSS patients, especially histopathological grade of LSGB. Furthermore, high IHC scores of membranous EpEX were independent risk factors for pSS, even for the pSS patients at early stage. The IHC scores of subcellular EpEX/EpICD were of great diagnostic value for pSS with high sensitivity (70-80%) and specificity (85-95%).

Conclusion

This study first found the aberrant expression pattern of EpCAM in LSG of pSS patients. The IHC scores of subcellular EpEX/EpICD were demonstrated to have the potential to act as diagnostic biomarkers for pSS.

Recommendations from the Brazilian society of rheumatology for the diagnosis of Sjögren's syndrome (Part I): glandular manifestations (systematic review)

BACKGROUND

Primary Sjögren's syndrome (pSS) is a systemic immune-mediated disease whose main characteristic is exocrine gland inflammation and, subsequent reduction in tear and saliva production. A delayed diagnosis is common due to the nonspecific clinical manifestations of disease. The aim of the present study was to develop recommendations for the diagnosis of glandular manifestations of pSS based on evidence and expert opinion. We conducted a systematic literature review to retrieve the best evidence available on the accuracy of diagnostic tests for pSS. We also held two in-person meetings with experts (rheumatologists, pathologists, ophthalmologists and dentists) to establish their level of agreement using the Delphi method. Ultimately, we generated 18 recommendations that aim to facilitate the diagnosis of the glandular manifestations of pSS.

CONCLUSION

The diagnosis of glandular manifestations of pSS is complex and multidisciplinary. It requires specific knowledge in the field of ophthalmology, immunology, pathology and imaging, making it compulsory for the rheumatologist to work with professionals from these different areas in order to improve accuracy and early diagnosis. Glandular dysfunction tests, ANA, RF, Anti-Ro, protein electrophoresis, urinalysis, blood count, C-Reactive protein, complement, testing for syphilis and viruses (HCV, HIV) and SGUS should be investigated when dryness or systemic manifestation are present. Minor salivary gland biopsy is recommended for all anti-Ro negative or incomplete criteria cases.

Evaluation of patients with dry eye for the presence of primary or secondary Sjӧgren's syndrome

PURPOSE

To assess the frequency of Sjӧgren's syndrome (SS), either primary or secondary to rheumatic disease, in a cohort of patients with aqueous-deficient dry eye and to determine the most accurate objective test for diagnosis of SS.

METHODS

A total of 111 patients with dry eye were recruited from Minia University's ​Ophthalmology Outpatient Clinic (69 patients) and Rheumatology Outpatient Clinic (42 patients). The patients were screened for aqueous tear-deficient dry eye by abnormal test results of Schirmer test I (<10 mm) and tear-film break-up time (<10 seconds) in at least one eye. The diagnosis of SS was made according to the 2012 American College of Rheumatology​ criteria. A complete work up for SS was performed, including clinical examination, serological tests, ocular tests, and labial salivary-gland biopsy (LSGB).

RESULTS

Of the 111 patients, 58 had aqueous-deficient dry eye: 23 in the ophthalmology clinic cohort (group I) and 35 in the rheumatology clinic cohort (group II). Three patients had pSS, and its frequency was 13% in group I and 5.2% among all studied patients. The ocular staining score is the most diagnostic ocular test (sensitivity 100% and specificity 90.9%). Anti-SSA/Ro antibody is the most accurate serological method (sensitivity 33.3% and specificity 100%). LSGB histopathology is the most diagnostic method for SS, with sensitivity, specificity, and positive and negative predictive values of 100%.

CONCLUSION

SS was detected with reasonable frequency among dry-eye patients, particularly pSS. Screening of dry eye for SS can select SS patients early in the disease course.

Severity of clinical dry eye manifestations influences protein expression in tear fluid of patients with primary Sjögren's syndrome

Ocular dryness is a characteristic feature of primary Sjögren’s syndrome (pSS). This may result in dry eye disease (DED), leading to damage of the ocular surface. Additional, non-invasive diagnostic techniques are needed when evaluating pSS patients. Hence, screening for disease-specific biomarkers in biological fluid could be promising. We have previously examined the proteome of tear fluid from pSS patients through Liquid chromatography-mass spectrometry (LC-MS), and conducted a thorough ocular evaluation of patients with pSS. In this study we further explored the association between dry eye manifestations and protein expression in tear fluid of pSS patients. Medical history of 27 patients and 32 healthy controls was gathered. Subjective complaints were registered through questionnaires. Objective findings including tear osmolarity, tear film break up time (TFBUT), Schirmer’s test, and ocular and corneal surface staining were also recorded. LC-MS was conducted formerly on tear fluid from all subjects in order to generate proteomic biomarker profiles. Scaffold was employed to analyse the LC-MS data for quantitative differences between patient and control groups, and the mean spectral counts were calculated for the five most upregulated proteins in relation to DED manifestations. Dysregulated cellular processes were identified in pSS patients using FunRichv3 enrichment analysis. The five most upregulated proteins previously identified in pSS patients were DNA (apurinic or apyrimidinic site) lyase (APEX1), thioredoxin-dependent peroxidase reductase (PRDX3), copine (CPNE1), aconitate hydratase (ACO2), and LIM domain only protein 7 (LMO7), in descending order. A significant increase in mean spectral counts for these proteins were observed in pSS patients with pathological DED manifestations compared to healthy controls (p<0.0001). Consequently, dysregulated cellular pathways involving innate and adaptive immunity were also detected. In conclusion, our observations suggest a relationship between presence of dry eye signs and upregulated proteins in tear fluid from patients with pSS. Further studies are needed in order to replicate the concepts explored and analyses performed in a greater cohort of pSS patients, where sensitivity and specificity of the methods conducted can also be verified further.

Parallel ocular and serologic course in a patient with early Sjogren's syndrome markers

Purpose

To report on a case of a young female with progressing dry eye symptoms and evolving autoimmune markers consistent with a presentation of early Sjogren's syndrome (SS).

Observations

A 32 year-old female presented with chronic dry eye symptoms refractory to artificial tears. Slit lamp examination revealed punctate epithelial erosions, decreased tear break-up time, and decreased tear lake bilaterally. Initial tests for ocular surface inflammation (InflammaDry, Quidel, San Diego) and systemic autoantibodies (antinuclear antibodies, anti-SSA/Ro and anti-SSB/La) were negative. After 4 months of persistent ocular symptoms and signs, ocular surface inflammation was detected via InflammaDry and blood results included a positive antinuclear antibody (1:160), rheumatoid factor (IgG 25.3 EU/ml), and carbonic anhydrase 6 (IgM 20.2 EU/ml), but persistently negative anti-SSA/Ro and anti-SSB/La antibodies.

Conclusions and importance

Taken together, these findings were suggestive of early Sjogren's syndrome with simultaneous appearance of both ocular and serum biomarkers. Novel autoantibodies testing in suspected patients can guide early intervention and potentially improve both the glandular and extra-glandular function in patients.

Minor Salivary Gland Biopsy-An Important Contributor to the Diagnosis of Sjögren Syndrome

PURPOSE

Sjögren syndrome (SS), although commonly associated with xerostomia and xerophthalmia, can present with extraglandular manifestations that make definitive diagnosis difficult. The 2 leading diagnostic classification systems include a positive minor salivary gland biopsy (MSGB) result as a major inclusion criterion. The purpose of this study was to better define the role of the MSGB in establishing a diagnosis of SS in a cohort of referred patients.

MATERIALS AND METHODS

This is a retrospective cohort study of patients referred to the Massachusetts General Hospital Department of Oral and Maxillofacial Surgery (Boston, MA) over a 5-year period to establish a diagnosis of SS. Inclusion criteria were complete information regarding presenting symptoms, reason for referral, and findings at MSGB. Incomplete records and referral for reasons other than presumptive SS resulted in exclusion. The MSGB and its role in definitive diagnosis based on accepted classification systems were evaluated for sensitivity, specificity, and positive and negative predictive values. Other variables of interest (demographics, pattern of referral, and symptomology) are described for the cohort.

RESULTS

Eighty-seven patients met the inclusion criteria. The mean age was 48.3 years (range, 19 to 74 yr) and 75 were women (86.2%). Fifteen MSGB results (17.2%) were positive based on the focus score histologic criteria. In 12 of 15 cases, the positive MSGB result allowed for a definitive diagnosis (80%). In 3 cases, other criteria allowed diagnosis without the contribution of the MSGB (sensitivity of MSGB, 80.0%; specificity, 87.5%; positive predictive value, 57.1%; negative predictive value, 95.5%).

CONCLUSION

The MSGB is an important contributor to a diagnosis of SS. When serology was negative, the MSGB often was the criterion that allowed the diagnosis to be established. It is the most frequently positive of the major criteria used by the 2 classification systems in current use.

The Potential Role for Early Biomarker Testing as Part of a Modern, Multidisciplinary Approach to Sjögren's Syndrome Diagnosis

Sjögren's syndrome (SS) is a chronic and progressive multisystem autoimmune disease typically managed by rheumatologists. Diagnostic delays are common, due in large part to the non-specific and variable nature of SS symptoms and the slow progression of disease. The hallmark characteristics of SS are dry eye and dry mouth, but there are a broad range of other possible symptoms such as joint and muscle pain, skin rashes, chronic dry cough, vaginal dryness, extremity numbness or tingling, and disabling fatigue. Given that dry eye and dry mouth are typically the earliest presenting complaints, eye care clinicians and dental professionals are often the first point of medical contact and can provide critical collaboration with rheumatologists to facilitate both timely diagnosis and ongoing care of patients with SS. Current diagnostic criteria advocated by the American College of Rheumatology are predicated on the presence of signs/symptoms suggestive of SS along with at least two objective factors such as traditional biomarker positivity, salivary gland biopsy findings, and/or presence of keratoconjunctivitis sicca. Traditional biomarkers for SS include the autoantibodies anti-Sjögren's syndrome-related antigen A (SS-A/Ro), anti-Sjögren's syndrome-related antigen B (SS-B/La), antinuclear antibody (ANA) titers, and rheumatoid factor (RF). While diagnostically useful, these biomarkers have low specificity for SS and are not always positive, especially in early cases of SS. Several newly-identified biomarkers for SS include autoantibodies to proteins specific to the salivary and lacrimal glands [SP-1 (salivary gland protein-1), PSP (parotid secretory protein), CA-6 (carbonic anhydrase VI)]. Data suggest that these novel biomarkers may appear earlier in the course of disease and are often identified in cases that test negative to traditional biomarkers. The Sjö^® test is a commercially available diagnostic panel that incorporates testing for traditional SS biomarkers (anti-SS-A/Ro, anti-SS-B/La, ANA, and RF), as well as three novel, proprietary early biomarkers (antibodies to SP-1, PSP, and CA-6) which provide greater sensitivity and specificity than traditional biomarker testing alone. Timely diagnosis of SS requires appropriate clinical vigilance for potential SS symptoms, referral and collaborative communication among rheumatology, ophthalmology, and oral care professions, and proactive differential work-up that includes both physical and laboratory evaluations.

Identification of potential saliva and tear biomarkers in primary Sjögren's syndrome, utilising the extraction of extracellular vesicles and proteomics analysis

Background

There is a long-lasting need for non-invasive, more accurate diagnostic techniques when evaluating primary Sjögren’s syndrome (pSS) patients. Incorporation of additional diagnostics involving screening for disease-specific biomarkers in biological fluid is a promising concept that requires further investigation. In the current study we aimed to explore novel disease biomarkers in saliva and tears from pSS patients.

Methods

Liquid chromatography-mass spectrometry (LC-MS) was performed on stimulated whole saliva and tears from 27 pSS patients and 32 healthy controls, and salivary and tear proteomic biomarker profiles were generated. LC-MS was also combined with size exclusion chromatography to isolate extracellular vesicles (EVs) from both fluids. Nanoparticle tracking analysis was conducted on joint fractions from the saliva and tears to determine size distribution and concentration of EVs. Further EV characterisation was performed by immunoaffinity capture of CD9-positive EVs using magnetic beads, detected by flow cytometry. The LC-MS data were analysed for quantitative differences between patient and control groups using Scaffold, and the proteins were further analysed using the Database for Annotation, Visualization and Integrated Discovery (DAVID), for gene ontology overrepresentation, and the Search Tool for the Retrieval of Interacting Genes/Proteins for protein-protein interaction network analysis.

Results

Upregulation of proteins involved in innate immunity (LCN2), cell signalling (CALM) and wound repair (GRN and CALML5) were detected in saliva in pSS. Saliva EVs also displayed biomarkers critical for activation of the innate immune system (SIRPA and LSP1) and adipocyte differentiation (APMAP). Tear analysis indicated overexpression of proteins involved in TNF-α signalling (CPNE1) and B cell survival (PRDX3). Moreover, neutrophil gelatinase-associated lipocalin was upregulated in saliva and tears in pSS. Consistently, DAVID analysis demonstrated pathways of the adaptive immune response in saliva, of cellular component assembly for saliva EVs, and of metabolism and protein folding in tears in pSS patients.

Conclusions

LC-MS of saliva and tears from pSS patients, solely and in combination with size-exclusion chromatography allowed screening for possible novel biomarkers encompassing both salivary and lacrimal disease target organs. This approach could provide additional diagnostic accuracy in pSS, and could possibly also be applied for staging and monitoring the disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1228-x) contains supplementary material, which is available to authorized users.

Evaluation of the oral component of Sjögren's syndrome: An overview

Sjögren's syndrome is a chronic autoimmune disorder characterized by lymphocytic infiltration, and consequently hypofunction of lacrimal and salivary glands. The loss of salivary function induces oral dryness (xerostomia). This review focuses on methods for determining salivary gland function including clinical signs, salivary flow rate measurements (sialometry), analysis of salivary composition (sialochemistry), histopathological and radiologic examinations, and other recent advanced techniques.

Adipose tissue is prominent in salivary glands of Sjögren's syndrome patients and appears to influence the microenvironment in these organs

A minor salivary gland (SG) biopsy with focal lymphocytic sialadenitis and a focus score of ≥1 is today's widely accepted pathological finding confirming the SG component of Sjögren's syndrome (SS). Adipocytes can occupy a large percentage of the SG area although little is known about their significance in SS lesions. This study aimed to characterise adipose tissue infiltration in labial SG biopsies from 27 SS patients and 28 non-SS sicca controls. Biopsies were evaluated by one oral pathologist and assessed for focus score, acinar atrophy, fatty replacement and non-specific chronic inflammation. Moreover, to explore the SG microenvironment, immunohistochemical staining of paraffin-embedded SG tissue was performed using interleukin-6 (IL-6). The fatty replacement was evident in all SS patients possessing autoantibodies (Ro/SSA and/or La/SSB) as well as a positive SG biopsy (focus score ≥1). Additionally, 62% of SS patients having autoantibodies but a negative biopsy showed fatty infiltration (FI) while non-SS controls demonstrated fatty replacement in only 32% of the cases. Overall, the SS group (mean age 53.0 years) had a significantly higher incidence (p value 0.005) of FI than the non-SS controls (mean age 54.8 years). Interestingly, adipocytes were located in IL-6 rich areas, and IL-6 positive adipocytes were detected. As fat deposition seems to be more recurrent in SGs affected by SS, we propose the assessment of adipose tissue replacement as a helpful tool for diagnostic evaluation in SS. Detection of IL-6 positive adipocytes suggests their involvement in immune reactions. Still, functional studies are needed to investigate the SG microenvironment further.