Sjögren's syndrome disease damage index and disease activity index: Scoring systems for the assessment of disease damage and disease activity in Sjögren's syndrome, derived from an analysis of a cohort of Italian patients

Clinimetric methods in Sjögren's syndrome

OBJECTIVE

Clinimetric tools are useful in both clinical practice and research of Sjögren's syndrome. These instruments assist in the establishment of diagnosis and in the evaluation of disease status. We reviewed the available methods used to monitor sicca signs and symptoms, fatigue, quality of life as well as activity/chronicity in SS.

METHODS

PubMed and MEDLINE database were searched for the keywords "keratoconjunctivitis sicca diagnosis," "dry eye and dry mouth assessment," "sialometry," "sialochemistry," "Sjögren's syndrome outcomes," "Sjögren's syndrome activity," "Sjögren's syndrome damage," "fatigue scales in Sjögren's syndrome," and "Sjögren's syndrome quality of life." All relevant articles and pertinent secondary references were reviewed.

RESULTS

As there is a moderate correlation between sicca symptoms and signs, the assessment of both is crucial. Most of the tests focus on oral and ocular dryness (vital dye staining, tear quantification, tear composition, sialometry, sialochemistry, etc.) and may not be disease specific. Symptoms such as dryness and fatigue have been evaluated with different instruments, being the PROFAD and ESSPRI disease-specific tools. Standardized measures for activity (SSDAI, SCAI, and ESSDAI) and chronicity (SSDDI and SSDI) indexes are currently used, however these methods still present limitations such as low external validity and cross-validation.

CONCLUSION

The heterogeneous nature of the disease and its slow progression, challenge the evaluation of these patients. The use of composite measures might increase our ability to diagnose and evaluate disease activity and cumulative irreversible organ injury in this disease. However the distinction among oral and ocular activity vs. damage is still a matter of research.

Allogeneic mesenchymal stem cell treatment alleviates experimental and clinical Sjögren syndrome

Sjögren syndrome (SS) is a systemic autoimmune disease characterized by dry mouth and eyes, and the cellular and molecular mechanisms for its pathogenesis are complex. Here we reveal, for the first time, that bone marrow mesenchymal stem cells in SS-like NOD/Ltj mice and human patients were defective in immunoregulatory functions. Importantly, treatment with mesenchymal stem cells (MSCs) suppressed autoimmunity and restored salivary gland secretory function in both mouse models and SS patients. MSC treatment directed T cells toward Treg and Th2, while suppressing Th17 and Tfh responses, and alleviated disease symptoms. Infused MSCs migrated toward the inflammatory regions in a stromal cell-derived factor-1-dependent manner, as neutralization of stromal cell-derived factor-1 ligand CXCR4 abolished the effectiveness of bone marrow mesenchymal stem cell treatment. Collectively, our study suggests that immunologic regulatory functions of MSCs play an important role in SS pathogenesis, and allogeneic MSC treatment may provide a novel, effective, and safe therapy for patients with SS.

Treating Sjögren's Syndrome: Insights for the Clinician

Sjögren's syndrome (SS) is a systemic autoimmune disease that affects the exocrine glands, mainly the salivary and lachrymal glands, with consequent persistent dryness of the mouth and eyes. In addition to the clinical manifestations related to the exocrine gland involvement, a consistent prevalence of patients may present systemic manifestations. Some of these can be ascribed to the periepithelial extension of lymphocytic infiltration whilst others are determined by an immunomediated process affecting small- or medium-size vessels. While the use of tear and saliva substitutes and local or systemic stimulation of residual secretions represent the mainstays of the therapy of sicca component, different immunomodulating or immunosuppressive agents are usually required to treat extraglandular features, similarly to what happens in other connective tissue diseases. In the last few years, the advancement in the understanding the pathogenetic mechanisms of this disorder and the availability of new biologic target therapies seem to offer completely new therapeutic options. The use of B cell depleting or modulating therapies has achieved promising results.

Biologic treatments in Sjögren's syndrome

Primary Sjögren's Syndrome (pSS) is characterized by focal lymphocytic infiltration of secretory exocrine glands associated with severe dryness of eyes and mouth in particular. Systemic features such as disabling fatigue, cutaneous vasculitis, lung, neurological, haematological or other systemic involvement also occur. Conventional immunosuppressive therapies such as corticosteroids or disease-modifying drugs, have been used in some patients with these systemic features with variable benefit. Current therapy for dryness is principally symptomatic although medications to stimulate residual glandular secretion can be helpful for appropriate individuals. As the pathogenesis of the condition becomes better understood, particularly, in recent years, the role of systemic B-cell activation, biologic therapies specifically targeted against molecules involved in disease pathogenesis represent a more targeted approach to therapeutic intervention. The greatest experience in pSS is with rituximab, an anti-CD20 (expressed on a subset of B-cells) monoclonal antibody already in use for the treatment of some B-cell lymphomas and rheumatoid arthritis. Randomised placebo-controlled studies in pSS are currently underway. This review discusses the rationale for using biologic therapies in pSS, the current data on rituximab and the potential use of other biologic therapies in pSS in the future.

Increased levels of circulating DNA in patients with systemic autoimmune diseases: A possible marker of disease activity in Sjögren's syndrome

High levels of serum and/or plasma circulating DNA (cDNA) have been described in patients with systemic autoimmune diseases (SADs). However, the role of this molecule has not been clarified. Our aim was to evaluate plasma cDNA levels in 48 systemic lupus erythematosus (SLE) and 44 primary Sjögren's syndrome (SS) patients, as compared with healthy and rheumatoid arthritis (RA) subjects, and to analyse their correlation with disease activity, disease damage and clinical manifestations. Plasma DNA was extracted using Qiagen columns and quantified by real-time quantitative PCR. Disease activity and damage were evaluated in both diseases by analysis of clinical and laboratory findings. Our results showed that plasma cDNA levels were significantly higher in patients with SS (mean ± SE: 32.0 ± 7.3 ng/ml) and with SLE (35.0 ± 9.0 ng/ml) than in controls (5.1 ± 1.1 ng/ml) (p < 0.0001 for both). Disease activity index correlated with cDNA levels in SS (p = 0.02), but not in SLE, and SS subjects with active disease displayed significantly higher cDNA levels with respect to inactive patients (p < 0.05). No correlation was found between plasma cDNA levels and disease damage indexes in either SLE or SS. These results indicate that increased plasma cDNA levels can been demonstrated in SLE and in SS patients with respect to healthy subjects. Interestingly, although cDNA levels did not correlate with indexes of disease damage in these disorders, a significant correlation between cDNA concentrations and disease activity was observed in SS, but not in SLE, suggesting a possible role of cDNA as non-invasive marker of disease activity. The different results obtained in these SADs may be explained by distinct disease pathogenesis or the influence of immunosuppressive and corticosteroid therapy that, unlike in SS, is usually employed in SLE.

Biological therapies in primary Sjögren's syndrome

INTRODUCTION

Primary Sjögren's syndrome (PSS) is a relatively common immune-mediated condition characterized by oral and ocular dryness, fatigue, musculoskeletal pain and poor health-related quality of life. Other extra-glandular organs can also be affected and PSS is associated with a markedly increased risk of lymphoma. Furthermore, the health-economic cost for PSS is substantial. There is currently no effective treatment available. With better understanding of the pathophysiology of PSS and advances in technologies, it is now possible to develop biological therapies to target specific molecules or molecular pathways that are important in PSS pathogenesis. Indeed, a limited number of biological therapies have already been tested in PSS with mixed successes.

AREAS COVERED

Published data on the use of biological therapies in PSS, the possible roles for other biological therapies and the potential challenges for their use.

EXPERT OPINION

The use of biological agents targeting key cellular and molecular pathways in PSS pathogenesis represents a promising therapeutic strategy. Clinical trials assessing the efficacy of biological therapies in PSS should be encouraged but patient selection and outcome measures used in these studies must be carefully considered to ensure that the true effects of biological therapies on the outcomes of PSS are being appropriately evaluated.

Pathogenesis of Sjögren's syndrome and therapeutic consequences

PURPOSE OF REVIEW

To summarize recent findings on new pathogenic mechanisms of interaction between genetic and environmental factors and between innate and adaptive immunity in primary Sjögren's syndrome and to reconcile pathogenesis and treatment by focusing on the crucial pathogenic steps that could be targeted by emerging therapies.

RECENT FINDINGS

Regarding genetic predisposition, the functional relevance of IRF5 and STAT4 gene polymorphisms in the activation of type I interferon pathways has been demonstrated. It has also been shown that the isolated stimulation of innate immunity in mice can result in dryness, which precedes lymphocytic infiltrates in salivary glands. In animal models, possible environmental triggers of the disease, such as oestrogen deficiency and/or infection by Epstein-Barr virus, can lead to innate immune followed by autoimmune epithelitis. The IFN-BAFF-B lymphocyte pathogenic axis is, therefore, targeted by numerous drugs currently in evaluation. The development of consensus disease activity scores and patient-related outcomes might help to initiate new controlled trials. The first positive randomized controlled trial with rituximab has been recently published.

SUMMARY

Hopefully, persistent and joint efforts by many teams to improve the knowledge on the pathogenesis of the disease may allow identification of new therapeutic targets in Sjögren's syndrome.

Hypomethylation and overexpression of CD70 (TNFSF7) in CD4+ T cells of patients with primary Sjögren's syndrome

BACKGROUND

Primary Sjögren's syndrome (pSS) is an autoimmune disease characterized by lymphocytic infiltration and the production of autoantibodies, leading to the destruction of lacrimal and salivary glands. However, very little is known about the pathogenesis of the disorder. CD70 (TNFSF7), a B cell costimulatory molecule, is overexpressed in CD4(+) T cells from patients with systemic erythematosus lupus (SLE) due to the hypomethylation of its promoter.

OBJECTIVE

In this study we asked whether the epigenetic regulation of CD70 expression is abnormal in pSS.

METHODS

CD70 levels in CD4(+) T cells from pSS patients, tinea pedis and healthy controls were measured by real-time RT-PCR and flow cytometry. Bisulphite sequencing was performed to determine the methylation status of the TNFSF7 promoter region.

RESULTS

CD70 expression was significantly elevated and correlated with a decrease in TNFSF7 promoter methylation in pSS CD4(+) T cells compared to controls.

CONCLUSIONS

Demethylation of the CD70 promoter regulatory elements contributes to CD70 overexpression in pSS CD4(+) T cells, and may contribute to autoreactivity.

Primary Sjögren's syndrome activity and damage indices comparison

BACKGROUND

Significant differences exist in outcome measures developed to assess patients with primary Sjögren's Syndrome (pSS). In this review, we have compared proposed indices.

METHODS

Three activity - SSDAI (SS Disease Activity Index), SCAI (Sjögren's Systemic Clinical Activity Index) and ESSDAI (EULAR SS Disease Activity Index) - and two damage indices - SSDDI (SS Disease Damage Index) and SSDI (SS Damage Index) have been analysed. Assessment 'tools' for perspectives of outcome (PROFAD - Profile of Fatigue and Discomfort, SF-36 - Medical Outcomes Study Short-Form 36-item questionnaire and ESSPRI - EULAR Sjögren's Syndrome Patients Reported Index) were also considered.

RESULTS

SSDAI and ESSDAI are global scores. SCAI is a composite score. Validity is a limitation for SSDAI and SCAI. ESSDAI is complemented by ESSPRI for the assessment of subjective features. It is more accurate in detecting changes in activity. Damage indices differ with respect to observation period and external validation but both have low content validity. Main limitations for all indices are: inclusion of patients with mainly mild stable disease and lack of information about the completion time of the forms.

CONCLUSIONS

All indices demonstrate a potentially useful benefit but further, larger studies are needed to assess reliability and sensitivity to change, to validate their use in clinical trials. Improvement in our knowledge of pathophysiology and clinical evolution of pSS is important to address unresolved issues: whether to include prognostic factors for an adverse outcome, an agreed definition of flare and most notably the distinction between activity and damage.

EULAR Sjogren's syndrome disease activity index: development of a consensus systemic disease activity index for primary Sjogren's syndrome

OBJECTIVE

To develop a disease activity index for patients with primary Sjögren's syndrome (SS): the European League Against Rheumatism (EULAR) Sjögren's syndrome disease activity index (ESSDAI).

METHODS

Thirty-nine SS experts participated in an international collaboration, promoted by EULAR, to develop the ESSDAI. Experts identified 12 organ-specific 'domains' contributing to disease activity. For each domain, features of disease activity were classified in three or four levels according to their severity. Data abstracted from 96 patients with systemic complications of primary SS were used to generate 702 realistic vignettes for which all possible systemic complications were represented. Using the 0-10 physician global assessment (PhGA) scale, each expert scored the disease activity of five patient profiles and 20 realistic vignettes. Multiple regression modelling, with PhGA used as the dependent variable, was used to estimate the weight of each domain.

RESULTS

All 12 domains were significantly associated with disease activity in the multivariate model, domain weights ranged from 1 to 6. The ESSDAI scores varied from 2 to 47 and were significantly correlated with PhGA for both real patient profiles and realistic vignettes (r=0.61 and r=0.58, respectively, p<0.001). Compared with 57 (59.4%) of the real patient profiles, 468 (66.7%) of the realistic vignettes were considered likely or very likely to be true.

CONCLUSIONS

The ESSDAI is a clinical index designed to measure disease activity in patients with primary SS. Once validated, such a standardised evaluation of primary SS should facilitate clinical research and be helpful as an outcome measure in clinical trials.

Accurate detection of changes in disease activity in primary Sjögren's syndrome by the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index

OBJECTIVE

To assess and compare the sensitivity to change of the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index (ESSDAI) with that of other primary Sjögren's syndrome (SS) disease activity indexes.

METHODS

We abstracted 96 patient profiles, including data on 3 successive visits (visits 1-3), from the medical charts of patients with primary SS. Patient profiles were scored with the ESSDAI, SS Disease Activity Index (SSDAI), and Sjögren's Systemic Clinical Activity Index (SCAI). Thirty-nine experts assessed 5 profiles for whether disease activity had improved, worsened, or remained stable at visits 2 and 3.

RESULTS

For improved patients, the standardized response means (SRMs) for all scores did not differ, and ranged from -1.08 to -1.38 between visits 1 and 2 and from -0.50 to -0.76 between visits 2 and 3. For patients with worsened activity, the SRMs between visits 1 and 2 and between visits 2 and 3 were +0.46 and +1.10 for the ESSDAI, -0.03 and +0.79 for the SSDAI, and +0.17 and +1.02 for the SCAI, respectively. For patients with stable activity, the SRMs between visits 1 and 2 and between visits 2 and 3 were 0.00 and -0.13 for the ESSDAI, -0.44 and -0.11 for the SSDAI, and -0.36 and +0.34 for the SCAI, respectively.

CONCLUSION

For patients with improved activity, the 3 disease activity indexes showed similar, large sensitivity to change. However, the ESSDAI seemed to detect changes in activity more accurately than other disease activity indexes. Notably, for patients with stable activity, the ESSDAI did not show erroneous improvement.

Periodontal Disease and Sjögren Syndrome: A Possible Correlation?

Sjögren syndrome (SS) is a chronic autoimmune rheumatic disease characterized by a progressive lymphocytic infiltration of exocrine glands, especially salivary and lachrymal ones, leading to xerostomia, parotid gland enlargement, and xerophthalmia. The aim of this study is to describe the capillaroscopic pattern of the interdental papilla in patients with SS and to evaluate a possible correlation with periodontal disease. Methods: A total of 25 patients affected by SS and 25 healthy controls were examined. The patients with conditions that compromise microcirculation, such as diabetes, hypertension, hyperlipidemia, or some pharmacological treatments, were not included in the study. All the patients were nonsmokers. Periodontal capillaroscopy has been used to investigate the features of microcirculation. Visibility, course, tortuosity, as well as the possible presence of microhemorrhage, the average caliber of the capillary loops, and the number of visible capillary loops per square millimeter were evaluated for each patient. Results: The results show evident alterations to the capillaries and a typical conformation of the interdental papilla microcirculation in patients with SS; it was possible to observe a reduced caliber of capillaries, as well as a greater number and tortuosity of capillary loops. Conclusion: This study shows that capillary alterations to patients with SS occur in gingival microcirculation.

Patient-reported outcomes including fatigue in primary Sjögren's syndrome

The hallmark of Sjögren's syndrome is focal lymphocytic infiltration of exocrine glands leading to mucosal dryness, particularly of the eyes and mouth. In addition, approximately 70% of patients report fatigue as a particularly prominent and disabling feature associated with reduced health-related quality of life. Other key patient-reported extraglandular symptoms include arthralgia, myalgia, and Raynaud's phenomenon. This article reviews these patient-reported features, their relationships with objective assessment of the disease, potential therapies for these symptoms, and how measurements of these symptoms are relevant to outcome assessment in clinical therapeutic trials.

Measurement of disease activity and damage in Sjögren's syndrome

Sjögren's syndrome (SS) is a systemic autoimmune disease that is characterized by an aggressive autoimmune response to epithelia, with consequent reduction of their secretions accompanied by sicca complaints. Systemic features may also be present in a subset of patients and may require more aggressive therapies. Improvements in knowledge concerning disease pathophysiology, combined with the availability of specifically targeted therapies able to modulate or block some of the most important pathologic mechanisms of the disease, may open totally new perspectives in the therapeutic approach to SS. The absence of reliable and validated outcome measures for SS is a major obstacle in performing clinical trials of new therapies in SS but studies devoted to defining outcome measurement instruments for this disorder have been performed or are in an advanced phases of completion.

Therapeutic potential for B-cell modulation in Sjögren's syndrome

B-cell hyperactivity has been recognized for a long time in Sjögren's syndrome. This B-cell activation is firstly polyclonal but can progress to monoclonal B-cell lymphoproliferation. This article addresses the therapeutic potential of B-cell modulation in Sjögren's syndrome.

Labial salivary gland biopsies in Sjögren's syndrome: still the gold standard?

OBJECTIVES

The accuracy and diagnostic benefits of the labial salivary gland (LSG) biopsy for Sjögren's syndrome (SS) have received mixed reviews. This study was conducted to assess (1) the inter-rater agreement among 5 pathologists, and (2) the relationship between biopsy findings and clinical disease parameters.

STUDY DESIGN

Three oral pathologists (OP) and two surgical pathologists (SP) provided independent diagnoses, focus scores, and plasma cell characterizations for 37 LSG biopsies. Inter-rater reliability was assessed using percentage of overall agreement and intraclass correlation coefficients. Relationships between diagnoses and clinical parameters were assessed by nonparametric correlations.

RESULTS

Overall agreement among the pathologists was poor, although the intra-specialty agreement was good. The ratings of OP were most highly correlated with serological measures, while those of SP were correlated with salivary flow rate and disease damage.

CONCLUSION

Since the LSG biopsy can be the determining factor in SS diagnoses, these demonstrated inconsistencies merit further consideration.

The Sjögren's Syndrome Damage Index--a damage index for use in clinical trials and observational studies in primary Sjögren's syndrome

OBJECTIVE

To validate a tool for assessment of accumulated damage in patients with Primary SS (PSS).

METHODS

Of the total 114 patients fulfilling American-European Consensus Group (AECG) criteria for PSS 104 were included in the study and assessed by rheumatologists at T (time) = 0 months and T = 12 months. On each occasion, damage and activity data, and autoantibody status were collected. SF-36 and Profile of Fatigue and Discomfort-Sicca Symptoms Inventory (PROFAD-SSI) questionnaires were completed. Cross-sectional analysis of this data was subject to a process of expert validation by 11 ophthalmologists, 14 oral medicine specialists and 8 rheumatologists. Items were removed from the index if >or= 50% of respondents recommended exclusion. Statistical validation was performed on remaining items. Spearman's rank analysis was used to investigate associations between damage scores and other disease status measures and Wilcoxon matched-pair analysis to assess sensitivity to change in the damage score.

RESULTS

Based on the expert validation, a 29-item damage score was agreed incorporating ocular, oral and systemic domains. Total damage score correlated with disease duration at study entry (r = 0.436; P < 0.001), physical function as measured by SF-36 (r = 0.250, T = 0 months; r = 0.261 T = 12 months) and activity as measured by the Sjögren's Systemic Clinical Activity Index (r = 0.213, T = 0 months; r = 0.215, T =12 months). Ocular damage score correlated with the 'eye dry' domain of PROFAD-SSI (r = 0.228, T = 0 months; r = 0.365, T = 12 months). Other associations not present on both assessments were considered clinically insignificant. On Wilcoxon analysis, the index was sensitive to change over 12 months (z = -3.262; P < 0.01).

CONCLUSION

This study begins validation of a tool for collection of longitudinal damage data in PSS. We recommend further trial in both the experimental and clinical environment.