Serological abnormalities that predict progression to systemic autoimmune rheumatic diseases in antinuclear antibody-positive individuals.

OBJECTIVE: We investigated the autoantibody (autoAb) profiles in ANA+ individuals lacking systemic autoimmune rheumatic disease (SARD) and early SARD patients to determine the key differences between these groups and identify factors that are associated with an increased risk of symptomatic progression within the next 2 years in ANA+ individuals. METHODS: Using custom antigen (Ag) microarrays, 144 IgM and IgG autoAbs were surveyed in 84 asymptomatic and 123 symptomatic (48 UCTD and 75 SARD patients) ANA+ individuals. AutoAbs were compared in ANA+ individuals lacking a SARD diagnosis with ≥2 years follow-up (n = 52), including all those who demonstrated progression (n = 14) during this period, with changes over time assessed in a representative subset. RESULTS: We show that ANA+ individuals have autoAb to many self-Ags that are not being captured by current screening techniques and very high levels of these autoAbs are predominantly restricted to early SARD patients, with SLE patients displaying reactivity to many more autoAgs than the other groups. In general, the symptoms that developed in progressors mirrored those seen in SARD patients with similar patterns of autoAbs. Only anti-Ro52 Abs were found to predict progression (positive predictive value 46%, negative predictive value 89%). Surprisingly, over 2 years of follow-up the levels of autoAbs remained remarkably stable regardless of whether individuals progressed or not. CONCLUSION: Our findings strongly argue that development of assays with an expanded set of auto-Ags and enhanced dynamic range would improve the diagnostic and prognostic ability of autoAb testing.

Interferon and interferon-induced cytokines as markers of impending clinical progression in ANA+ individuals without a systemic autoimmune rheumatic disease diagnosis.

BACKGROUND: Elevated levels of interferons (IFNs) are a characteristic feature of systemic autoimmune rheumatic diseases (SARDs) and may be useful in predicting impending symptomatic progression in anti-nuclear antibody-positive (ANA+) individuals lacking a SARD diagnosis. Typically, these are measured by their effect on gene expression in the blood, which has limited their utility in clinical settings. Here, we assessed whether the measurement of serum IFN-α or selected IFN-induced cytokines accurately mirrors IFN-induced gene expression in ANA+ individuals and investigated their utility as biomarkers of clinical progression. METHODS: A total of 280 subjects were studied, including 50 ANA- healthy controls, 160 ANA+ individuals without a SARD diagnosis (96 asymptomatic, 64 with undifferentiated connective tissue disease), and 70 SARD patients. IFN-induced gene expression was measured by nanoString and cytokine levels by ELISA or Simoa. ANA+ individuals lacking a SARD diagnosis who had the new onset of SARD criteria over the subsequent 2 years were defined as progressors. RESULTS: Measurement of IFN-α levels by high-sensitivity ELISA or Simoa correlated much better with IFN-induced gene expression than measurement of CXCL-10 or Galectin-9 levels. Despite this, high CXCL-10 and Galectin-9 levels were better predictors of subsequent progression in ANA+ individuals than measures of IFN-α or IFN-induced gene expression with the optimal combination of predictive cytokines (CXCL-10 and IFN-α as measured by ELISA), resulting in a specificity and positive predictive value of 100%. CONCLUSION: Easily performed ELISA assays for CXCL-10 and IFN-α can be used to predict ANA+ individuals at high risk of imminent symptomatic progression.

Whole stimulated salivary flow: correlation with the pathology of inflammation and damage in minor salivary gland biopsy specimens from patients with primary Sjögren's syndrome but not patients with sicca.

OBJECTIVE: To determine which measure of the salivary flow rate, stimulated or unstimulated, is most strongly associated with pathologic changes in minor salivary gland (MSG) biopsy specimens, and to explore the correlation of salivary flow with oral surface damage, disease duration, and symptom severity in patients with primary Sjögren's syndrome (SS). METHODS: In all patients (n = 32), a biopsy of the MSG was performed, and stimulated salivary flow was assessed. Beginning in 2002, unstimulated salivary flow was also assessed. Scores for the severity of symptoms, according to the decayed/missing/filled teeth (DMF) index, were recorded. Associations between measures of salivary flow and covariates characterizing pathology were examined. RESULTS: A definite association between stimulated salivary flow and the MSG focus score, the grade of MSG fibrosis, the duration of dry mouth symptoms, and the DMF score was observed. In contrast, unstimulated salivary flow was not associated with fibrosis, atrophy, the DMF score, or the duration of dry mouth symptoms. In patients with primary SS, the DMF score was associated with pathologic changes in the MSG. Among patients with sicca, 57.9% had an abnormal unstimulated salivary flow rate (versus 82.4% of patients with primary SS), and 15.2% had an abnormal stimulated salivary flow rate (versus 61.8% of patients with primary SS). Among patients with sicca, neither stimulated salivary flow nor unstimulated salivary flow was associated with the degree of fibrosis or atrophy or with the DMF score. CONCLUSION: Compared with unstimulated salivary flow, stimulated salivary flow appeared to be a better measure of inflammation (according to the focus score) and fibrosis. In patients with sicca, the unstimulated salivary flow rate appeared to be abnormal more commonly compared with the stimulated salivary flow rate. In the future, stimulated salivary flow may serve as a noninvasive surrogate biomarker of inflammation and fibrosis as well as a measure of response to treatment in patients with primary SS.

Content Validity of Sjögren's Syndrome Symptom Diary and Functional Assessment of Chronic Illness Therapy-Fatigue in Patients with Sjögren's.

INTRODUCTION: Sjögren's Syndrome Symptom Diary (SSSD) and Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) are patient-reported outcome (PRO) instruments assessing Sjögren's symptoms. Original SSSD items have demonstrated content validity, however qualitative evidence supporting the updated 'tiredness' item and two new supplementary items is lacking. Although well established and validated in other rheumatic diseases, there is no qualitative evidence supporting content validity of FACIT-F in Sjögren's. This study addressed these evidence gaps to support use of SSSD and FACIT-F as clinical trial endpoints, in clinical practice and in other research settings. METHODS: Qualitative, semi-structured telephone interviews were conducted with patients with Sjögren's (n = 12) and expert Sjögren's physicians (n = 10). Patient interviews explored content validity (e.g., understanding and relevance) of the new and updated SSSD items, perceptions of item and total score meaningful change on SSSD, and understanding and relevance of FACIT-F items. Physician interviews explored opinions on various SSSD scoring approaches. RESULTS: The new and updated SSSD items and FACIT-F demonstrated good content validity. Most patients considered a two-point improvement on most SSSD items meaningful, as well as a one- or two-point total score improvement. Most physicians reported tracking changes in patient responses to individual items as the most appropriate SSSD scoring approach. CONCLUSIONS: SSSD and FACIT-F are content valid in a Sjögren's population, meeting an important criterion to support their use as clinical trial endpoints, but also their use in clinical practice and other research settings. Qualitative data exploring meaningful change will be valuable in supporting psychometrically derived responder definitions.

Sjögren's Syndrome Symptom Diary (SSSD) and Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) are questionnaires completed by individuals with Sjögren's to assess the severity of their symptoms. It is important to show that these questionnaires are well understood and relevant to the individuals who complete them. Therefore, interviews were conducted with individuals with Sjögren's to explore their understanding and relevance of new and updated SSSD questions. Similarly, the interviews explored whether the FACIT-F questionnaire was well understood and relevant to individuals with Sjögren's, as this has not been explored before. Interviews were also conducted with expert Sjögren's physicians to explore the best approach to scoring SSSD (e.g., calculating a total score or looking at scores on individual items). The new and updated SSSD questions and the FACIT-F questionnaire were well understood and considered relevant by most individuals with Sjögren's. This suggests these questionnaires are appropriate for use in Sjögren's clinical trials, clinical practice, and other research settings. Most individuals with Sjögren's considered an improvement of two points on individual SSSD questions to be important, as well as a one- or two-point improvement in their total SSSD score. Most physicians agreed on the best approach to scoring SSSD.

Qualitative Research with Patients and Physicians to Assess Content Validity and Meaningful Change on ESSDAI and ESSPRI in Sjögren's.

INTRODUCTION: European Alliance of Associations for Rheumatology (EULAR) Sjögren's Syndrome Disease Activity Index (ESSDAI) is a clinician-reported outcome (ClinRO) instrument, assessing Sjögren's disease activity from the physician perspective. EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) is a patient-reported outcome (PRO) instrument, assessing patient-defined Sjögren's symptom severity. Both instruments are commonly used as clinical trial endpoints and have been psychometrically validated. However, qualitative evidence supporting content validity and what constitutes a meaningful change is limited. Qualitative evidence supporting Physician/Patient Global Assessment of disease activity and symptom severity (PhGA/PaGA) items used within anchor-based analyses for ESSDAI/ESSPRI is also lacking. METHODS: Qualitative, semi-structured, telephone/video interviews were conducted with patients with Sjögren's (n = 12) and physicians who specialise in Sjögren's (n = 10). Interviews explored: appropriateness of ESSDAI domain weights and meaningful improvements on domain/total scores from the physician perspective, appropriateness of ESSPRI's 2-week recall period from the patient/physician perspective, patients' perspectives on meaningful improvements in ESSPRI total scores, and patients'/physicians' interpretation of PhGA/PaGA items. RESULTS: Most ESSDAI domain weights were considered clinically appropriate. Generally, a one-category improvement in domain-level scores and a 3-point improvement in total ESSDAI scores were considered clinically meaningful. Most patients/physicians considered ESSPRI's 2-week recall period appropriate, and patients considered a 1-to-2-point ESSPRI total score improvement meaningful. PhGA/PaGA items developed for use as ESSDAI/ESSPRI anchors were consistently interpreted. CONCLUSIONS: The findings support use of ESSDAI and ESSPRI as Sjögren's clinical trials endpoints, as well as in clinical practice and other research settings. Qualitative data exploring meaningful change supports existing minimal clinically important improvement (MCII) thresholds.

European Alliance of Associations for Rheumatology (EULAR) Sjögren's Syndrome Disease Activity Index (ESSDAI) is an assessment used by physicians to measure how active Sjögren's is in individuals with the condition. EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) is a questionnaire completed by individuals with Sjögren's to assess the severity of their symptoms. It is important to show that ESSDAI and ESSPRI are considered appropriate by physicians and individuals with Sjögren's, respectively, and that ESSPRI is well understood by individuals with Sjögren's completing the questionnaire. Therefore, interviews were conducted with physicians who specialise in Sjögren's to explore the appropriateness of ESSDAI, the level of improvement on the assessment that would be important to individuals with Sjögren's, and the appropriateness of the ESSPRI recall period (i.e. whether it is acceptable to ask individuals to remember their symptoms over the past 2 weeks). Interviews were also conducted with individuals with Sjögren's to explore their understanding and relevance of ESSPRI (including the 2-week recall period) and the level of improvement on the questionnaire that would be important to them. Most physicians and patients considered ESSDAI and ESSPRI appropriate, supporting their use in a range of settings including Sjögren's clinical trials, clinical practice and other research settings. Most physicians reported that a 3-point improvement in ESSDAI total score would be meaningful to individuals with Sjögren's. Individuals with Sjögren's reported that a 1-to-2-point improvement in ESSPRI total score would be meaningful.

Altered Balance of Pro-Inflammatory Immune Cells to T Regulatory Cells Differentiates Symptomatic From Asymptomatic Individuals With Anti-Nuclear Antibodies.

Systemic Autoimmune Rheumatic Diseases (SARDs) are characterized by the production of anti-nuclear antibodies (ANAs). ANAs are also seen in healthy individuals and can be detected years before disease onset in SARD. Both the immunological changes that promote development of clinical symptoms in SARD and those that prevent autoimmunity in asymptomatic ANA+ individuals (ANA+ NS) remain largely unexplored. To address this question, we used flow cytometry to examine peripheral blood immune populations in ANA+ individuals, with and without SARD, including 20 individuals who subsequently demonstrated symptom progression. Several immune populations were expanded in ANA+ individuals with and without SARD, as compared with ANA- healthy controls, particularly follicular and peripheral T helper, and antibody-producing B cell subsets. In ANA+ NS individuals, there were significant increases in T regulatory subsets and TGF-ß1 that normalized in SARD patients, whereas in SARD patients there were increases in Th2 and Th17 helper cell levels as compared with ANA+ NS individuals, resulting in a shift in the balance between inflammatory and regulatory T cell subsets. Patients with SARD also had increases in the proportion of pro-inflammatory innate immune cell populations, such as CD14+ myeloid dendritic cells, and intermediate and non-classical monocytes, as compared to ANA+ NS individuals. When comparing ANA+ individuals without SARD who progressed clinically over the subsequent 2 years with those who did not, we found that progressors had significantly increased T and B cell activation, as well as increased levels of LAG3+ T regulatory cells and TGF-ß1. Collectively, our findings suggest that active immunoregulation prevents clinical autoimmunity in ANA+ NS and that this becomes impaired in patients who progress to SARD, resulting in an imbalance favoring inflammation.

Correlation Between Subjective and Objective Severity of Oral and Ocular Dryness in Primary Sjögren Syndrome.

OBJECTIVE: Sjögren syndrome (SS) is a common autoimmune disease primarily affecting the eyes and mouth. With no single gold standard test for its diagnosis, accurate identification of patients with SS continues to be challenging. We aimed to assess the correlation of ocular and oral symptoms of dryness with objective measures in order to evaluate reliability in the screening of primary SS (pSS) in clinical practice. METHODS: We conducted a cross-sectional analysis of pre-screened pSS and sicca control patients assessed in the Multidisciplinary Sjögren's Clinic at the University Health Network in Toronto. The signs, symptoms, and objective measure of oral and ocular dryness and damage of each patient were prospectively recorded using a standardized protocol. RESULTS: Subjective measures of severity for xerophthalmia and xerostomia correlated in general with objective severity. Oral symptoms tend to have a stronger correlation with objective findings than ocular symptoms. Many patients with few or insignificant eye symptoms had profound ocular dryness and damage. Similarly, some patients with few or no symptoms of oral dryness had profound objective salivary hypofunction. The absence of symptoms does not rule out profound eye and mouth dryness or damage. CONCLUSION: Although objective measures of xerostomia may not be practical for general population screening, it is crucial that practicing specialists perform objective testing of all patients suspected of pSS, instead of relying on symptoms. Without objective testing, the physician cannot ensure the diagnosis of pSS and that the existence of significant damage is not overlooked and left untreated.

Factor analysis of the clinical characteristics of primary Sjogren syndrome.

PURPOSE: The purpose of this study was to use factor analysis to analyze 90 clinical characteristics of a cohort of 231 patients with primary Sjogren syndrome (pSS). METHODS: The records of all patients seen at the University Health Network Sjogren Syndrome Clinic from October 1992 to July 2006 were reviewed and documented. Those diagnosed as pSS by the American European Consensus Criteria of 2002 were included. The 90 clinical variables, including health history, blood analysis, symptoms of dry eye and dry mouth, salivary flow and biopsy, tear flow and staining, were analyzed by factor analysis. RESULTS: Two hundred thirty-one patients with pSS charts were reviewed, and 90 variables were recorded. Factor analysis resulted in three factors: factor 1: ocular surface staining, factor 2: antimicrosomal antibodies and antithyroid antibodies, and factor 3: serum anti-Ro and anti-La. CONCLUSIONS: Ocular surface staining accounted for the greatest variance in this population of patients with pSS.

Comparison of Effect on Sicca Symptoms of Anticentromere Antibody-positive Sjögren Syndrome and Primary Sjögren Syndrome Alone.

OBJECTIVE: To determine whether positive anticentromere antibody (ACA) serology affects the severity of sicca symptoms in patients with primary Sjögren syndrome (pSS). METHODS: Evaluation to detect subjective and objective sicca symptoms included questionnaires, physical examination, and pathology. Cases of pSS were classified according to the 2002 American-European Consensus Group (AECG) criteria. All patients were evaluated for presence of anti-Ro, anti-La, and ACA serology. Patients with pSS were categorized into ACA+ SS and ACA-SS. The groups were compared for measures of severity of oral and ocular sicca. RESULTS: The pSS group had 446 patients, of whom 26 were ACA+ SS. Subjective ocular sicca measured 7.0 ± 2.4 (out of 10) in ACA+ SS and 6.4 ± 2.6 in ACA-SS (p = 0.197). Objective ocular sicca measured 3.2 mm ± 1.8 mm/5 min in ACA+ SS and 4.2 mm ± 4.4 mm/5 min in ACA-SS (p = 0.038). Subjective oral sicca measured 8.5 ± 1.4 in ACA+ SS and 6.7 ± 2.4 in ACA-SS (p < 0.001). Objective oral sicca measured 0.1 ml ± 0.2 ml/15 min in ACA+ SS and 0.4 ml ± 1.0 ml/15 min in ACA-SS (p < 0.001). Only 35% of ACA+ patients with SS were anti-Ro-positive or anti-La-positive compared with 77% of the ACA-patients with SS (p < 0.001). There was no significant difference in minor salivary gland fibrosis or focus scores between ACA+ SS and ACA-patients with SS. CONCLUSION: ACA+ SS is associated with more severe objective ocular sicca and more severe subjective and objective oral sicca compared to ACA-SS. The majority of ACA+ patients with SS meet AECG criteria for pSS despite negative serology for anti-Ro/La antibodies.

Fatigue severity in anti-nuclear antibody-positive individuals does not correlate with pro-inflammatory cytokine levels or predict imminent progression to symptomatic disease.

BACKGROUND: Fatigue is a common symptom of systemic autoimmune rheumatic disease (SARD). Patients with SARD have a protracted pre-clinical phase during which progressive immunologic derangements occur culminating in disease. In this study, we sought to determine when fatigue develops and whether its presence correlates with inflammatory factors or predicts disease progression. METHODS: Anti-nuclear antibody (ANA)-negative healthy controls (HCs) and ANA-positive participants with no criteria, at least one clinical criteria (undifferentiated connective tissue disease, UCTD), or meeting SARD classification criteria were recruited. Fatigue was assessed using a modified version of the FACIT-F questionnaire and the presence of fibromyalgia determined using a questionnaire based on the modified 2010 ACR criteria. Peripheral blood expression of five IFN-induced genes was quantified by NanoString and the levels of IL-1ß, IL-6, or TNF-α by ELISA. RESULTS: Fatigue was as prevalent and severe in individuals lacking SARD criteria as it was in UCTD and SARD. Overall, ~ 1/3 of ANA+ subjects met fibromyalgia criteria, with no differences between sub-groups. Although fatigue was more severe in these individuals, those lacking fibromyalgia remained significantly more fatigued than ANA- HC. However, even in these subjects, fatigue correlated with the widespread pain index and symptom severity scores on the fibromyalgia questionnaire. Fatigue was not associated with elevated cytokine levels in any of the ANA+ sub-groups and did not predict imminent disease progression. CONCLUSIONS: Fatigue is common in ANA+ individuals lacking sufficient criteria for a SARD diagnosis, correlates with fibromyalgia-related symptoms, and is not associated with inflammation or predictive of disease progression.

Epidemiology and Survival of Systemic Sclerosis-Systemic Lupus Erythematosus Overlap Syndrome.

OBJECTIVE: Systemic sclerosis (SSc) may overlap with systemic lupus erythematous (SLE). Little is known about the epidemiology, clinical characteristics, and survival of SSc-SLE overlap. We evaluated the prevalence of SSc-SLE overlap and differences in SSc characteristics, and compared survival with SSc without SLE. METHODS: A cohort study was conducted including subjects who fulfilled the American College of Rheumatology (ACR)/European League Against Rheumatism classification criteria for SSc and/or the ACR criteria for SLE. The primary outcome was time from diagnosis to all-cause mortality. Survival was evaluated using Kaplan-Meier and Cox proportional hazard models. RESULTS: We identified 1252 subjects (SSc: n = 1166, SSc-SLE: n = 86) with an SSc-SLE prevalence of 6.8%. Those with SSc-SLE were younger at diagnosis (37.9 yrs vs 47.9 yrs, p < 0.001), more frequently East Asian (5.5% vs 20%) or South Asian (5.1% vs 12%), had lupus anticoagulant (6% vs 0.3%, p < 0.001), anticardiolipin antibody (6% vs 0.9%, p < 0.001), and pulmonary arterial hypertension (PAH; 52% vs 31%, p < 0.001). Those with SSc-SLE less frequently had calcinosis (13% vs 27%, p = 0.007), telangiectasia (49% vs 75%, p < 0.001), and diffuse subtype (12% vs 35%, p < 0.001). There were no significant differences in the occurrence of renal crisis (7% vs 7%), interstitial lung disease (ILD; 41% vs 34%), and digital ulcers (38% vs 32%). Those with SSc-SLE had better median survival time (26.1 vs 22.4 yrs), but this was not statistically significant (log-rank p = 0.06). Female sex and diffuse subtype attenuated survival differences between groups (HR 1.07, 95% CI 0.67-1.67). CONCLUSION: Patients with SSc-SLE are younger at diagnosis, more frequently have PAH, and less frequently have cutaneous manifestations of SSc. They should be monitored for ILD, renal crisis, and digital ulcers.

The presence of anti-nuclear antibodies alone is associated with changes in B cell activation and T follicular helper cells similar to those in systemic autoimmune rheumatic disease.

BACKGROUND: Diagnosis of systemic autoimmune rheumatic diseases (SARD) relies on the presence of hallmark anti-nuclear antibodies (ANA), many of which can be detected years before clinical manifestations. However, ANAs are also seen in healthy individuals, most of whom will not develop SARD. Here, we examined a unique cohort of asymptomatic ANA+ individuals to determine whether they share any of the cellular immunologic features seen in SARD. METHODS: Healthy ANA- controls and ANA+ (ANA ≥1:160 by immunofluorescence) participants with no SARD criteria, with at least one criterion (undifferentiated connective tissue disease (UCTD)), or meeting SARD classification criteria were recruited. Peripheral blood cellular immunological changes were assessed by flow cytometry and transcript levels of BAFF, interferon (IFN)-induced and plasma cell-expressed genes were quantified by NanoString. RESULTS: A number of the immunologic abnormalities seen in SARD, including changes in peripheral B (switched memory) and T (iNKT, T regulatory, activated memory T follicular helper) subsets and B cell activation, were also seen in asymptomatic ANA+ subjects and those with UCTD. The extent of these immunologic changes correlated with ANA titer or the number of different specific ANAs produced. Principal component analysis of the cellular data indicated that a significant proportion of asymptomatic ANA+ subjects and subjects with UCTD clustered  with patients with early SARD, rather than ANA- healthy controls. CONCLUSIONS: ANA production is associated with altered T and B cell activation even in asymptomatic individuals. Some of the currently accepted cellular features of SARD may be associated with ANA production rather than the immunologic events that cause symptoms in SARD.

Office capillaroscopy in systemic sclerosis.

The aims of this study are to assess the reliability of two office techniques, the ophthalmoscope and the Dermlite dermatoscope, and to detect nailfold capillaroscopy abnormalities in systemic sclerosis (SSc). Two separate studies were performed. In the first, the nailfolds of two fingers on one hand of 13 SSc patients and two normals were examined by four rheumatologists using an ophthalmoscope. In the second, the nailfolds of the two fingers of each hand of six SSc patients and two normals were examined by six rheumatologists with a Dermlite dermatoscope. Widefield capillary microscopy was performed by one observer in the ophthalmoscope study to assess validity. The examiners determined the presence or absence of dilated loops, giant capillary loops, and/or avascular areas on each digit. The kappa coefficient was calculated to demonstrate agreement. With the ophtalmoscope, the inter-observer kappa coefficients were 0.43, 0.54, and 0.19; the average intra-observer agreements were 0.61, 0.56, and 0.31; and the ophthalmoscope-microscope agreement were 0.63, 0.52, and <0.1 for dilated capillaries, giant capillaries, and avascular areas, respectively. With the dermatoscope, the kappa values for inter-observer reliability were 0.63, 0.40, and 0.20; and intra-observer reliability was 0.71, 0.55, and 0.40 for dilated capillaries, giant capillaries, and avascular areas, respectively. The ophthalmoscope and the dermatoscope provide moderate to substantial reliability to detect the presence of giant and dilated capillaries but poor inter-observer agreement for avascular areas. The ophthalmoscope is valid when compared to the microscope for detecting giant or dilated capillaries. We conclude that these techniques are useful office tools to detect capillary abnormalities in SSc.

A Challenging Diagnosis of IgG4-Related Disease When Understanding Limitations of Laboratory Testing Was Pivotal.

A 76-year-old man was incidentally found on a CT scan to have lymphadenopathy and bilateral kidney enlargement suggestive of infiltrative renal disease. He was largely asymptomatic but had bilateral salivary and lacrimal gland enlargement. A grossly elevated serum IgG (>70 g/L) with concomitant suppression of other immunoglobulins, a small IgG restriction, and a parotid biopsy revealing lymphoplasmacytic infiltrate with slight kappa light chain excess all suggested a lymphoproliferative disorder (LPD). The diagnostic workup was further confounded by a normal serum IgG4 concentration. Moreover, bone marrow and renal biopsies did not reveal evidence of LPD. Discussion with the laboratory not only clarified that the markedly increased total IgG could not be accounted for by the small IgG restriction, but also identified a discrepancy in the IgG4 measurement. Repeat analysis of a follow-up sample revealed an elevated IgG4 of 5.94 (reference interval: 0.039-0.864) g/L, which prompted a repeat parotid biopsy that showed predominant IgG4+ lymphocytic infiltrates. Despite the deluding presentations, a final diagnosis of IgG4-related disease (IgG4-RD) was made based on elevated serum IgG4 concentrations and histopathological findings. This case highlights the importance of recognizing limitations of laboratory testing and the benefit of close communications among clinical subspecialties and the laboratory.

Presence of an interferon signature in individuals who are anti-nuclear antibody positive lacking a systemic autoimmune rheumatic disease diagnosis.

BACKGROUND: Elevated levels of type I interferons (IFNs) are a characteristic feature of the systemic autoimmune rheumatic diseases (SARDs) and are thought to play an important pathogenic role. However, it is unknown whether these elevations are seen in anti-nuclear antibody-positive (ANA+) individuals who lack sufficient criteria for a SARD diagnosis. We examined IFN-induced gene expression in asymptomatic ANA+ individuals and patients with undifferentiated connective tissue disease (UCTD) to address this question. METHODS: Healthy ANA- control subjects and ANA+ titre (≥1:160 by immunofluorescence) participants meeting no criteria, meeting at least one criterion (UCTD) or meeting SARD classification criteria were recruited. Whole peripheral blood IFN-induced and BAFF gene expression were quantified using NanoString technology. The normalized levels of five IFN-induced genes were summed to produce an IFN5 score. RESULTS: The mean IFN5 scores were increased in all ANA+ participant subsets as compared with healthy control subjects. We found that 36.8% of asymptomatic ANA+ and 50% of UCTD participants had IFN5 scores >2 SD above the mean for healthy control subjects. In all ANA+ subsets, the IFN5 score correlated with the presence of anti-Ro/La antibodies. In the asymptomatic ANA+ subset, this score also correlated with the ANA titre, whereas in the other ANA+ subsets, it correlated with the number of different ANA specificities. Development of new SARD criteria was seen in individuals with normal and high IFN5 scores. CONCLUSIONS: An IFN signature is seen in a significant proportion of ANA+ individuals and appears to be associated with ANA titre and type of autoantibodies, rather than with the presence or development of clinical SARD symptoms.

EULAR Sjögren's syndrome disease activity index (ESSDAI): a user guide.

The EULAR Sjögren's syndrome (SS) disease activity index (ESSDAI) is a systemic disease activity index that was designed to measure disease activity in patients with primary SS. With the growing use of the ESSDAI, some domains appear to be more challenging to rate than others. The ESSDAI is now in use as a gold standard to measure disease activity in clinical studies, and as an outcome measure, even a primary outcome measure, in current randomised clinical trials. Therefore, ensuring an accurate and reproducible rating of each domain, by providing a more detailed definition of each domain, has emerged as an urgent need. The purpose of the present article is to provide a user guide for the ESSDAI. This guide provides definitions and precisions on the rating of each domain. It also includes some minor improvement of the score to integrate advance in knowledge of disease manifestations. This user guide may help clinicians to use the ESSDAI, and increase the reliability of rating and consequently of the ability to detect true changes over time. This better appraisal of ESSDAI items, along with the recent definition of disease activity levels and minimal clinically important change, will improve the assessment of patients with primary SS and facilitate the demonstration of effectiveness of treatment for patients with primary SS.

Correlation between corneal sensitivity, subjective dry eye symptoms and corneal staining in Sjögren's syndrome.

BACKGROUND: Previous studies have shown a poor correlation between dry eye symptoms and objective clinical signs in patients with Sjögren's syndrome. We examined the hypothesis that reduced corneal sensitivity is associated with increased ocular surface disease and reduced symptoms in patients with Sjögren's syndrome. METHODS: Eighteen subjects with a diagnosis of Sjögren's syndrome attending a Sjögren's clinic participated in the study. All participants completed the Ocular Surface Disease Index (OSDI) and the Symptom Severity of Discomfort (SSD) scale and answered a question regarding overall severity of dry eye symptoms. The subjects underwent measurement of best-corrected Snellen visual acuity, corneal sensitivity testing with the Cochet-Bonnet esthesiometer, fluorescein and lissamine green staining of the cornea, Schirmer's test I and determination of the tear film break-up time. The results were analysed using Pearson correlational analysis. RESULTS: Both fluorescein and lissamine green staining of the cornea correlated negatively with central corneal sensation (r = -0.3542, p = 0.034, and r = -0.3748, p = 0.029 respectively), indicating that corneal sensation was reduced with increased ocular surface disease. The overall symptom severity correlated negatively with lissamine green staining of the cornea (r = -0.4310, p = 0.011), suggesting reduced symptoms with increased corneal disease. INTERPRETATION: Reduced corneal sensation correlated with increased ocular surface disease. Ocular surface disease similarly demonstrated a reciprocal relation with patients' dry eye symptoms. Consequently, we found that patients with Sjogren's syndrome with advanced corneal staining tended to have fewer dry eye symptoms than patients with less corneal staining.