Autoantibodies against the NineTeen complex and U5 RNP in systemic sclerosis.

ObjectiveMultiple spliceosome components are known autoantigens in systemic sclerosis (SSc). Here we aim to identify new and characterize rare anti-spliceosomal autoantibodies in patients with SSc without known autoantibody specificity. MethodsSera that precipitated spliceosome subcomplexes, as detected by immunoprecipitation-mass spectrometry (IP-MS), were identified from a database of 106 patients with SSc without known autoantibody specificity. New autoantibody specificities were confirmed with immunoprecipitation-western blot. The IP-MS pattern of new anti-spliceosomal autoantibodies was compared with anti-U1 RNP-positive sera of patients with different systemic autoimmune rheumatic diseases and anti-SmD-positive sera of patients with systemic lupus erythematosus (n = 24). ResultsThe NineTeen Complex (NTC) was identified and confirmed as new spliceosomal autoantigen in one patient with SSc. U5 RNP, as well as additional splicing factors, were precipitated by the serum of another patient with SSc. The IP-MS patterns of anti-NTC and anti-U5 RNP autoantibodies were distinct from those of anti-U1 RNP- and anti-SmD-positive sera. Furthermore, there was no difference in IP-MS patterns between a limited number of anti-U1 RNP-positive sera of patients with different systemic autoimmune rheumatic diseases. ConclusionAnti-NTC autoantibodies are a new anti-spliceosomal autoantibody specificity, here first identified in a patient with SSc. Anti-U5 RNP autoantibodies are a distinct but rare anti-spliceosomal autoantibody specificity. All major spliceosomal subcomplexes have now been described as target of autoantibodies in systemic autoimmune diseases.

Identification of new telomere- and telomerase-associated autoantigens in systemic sclerosis.

PURPOSE: In up to 20% of patients with systemic sclerosis (SSc) no known autoantibody specificity can be identified. Recently discovered autoantigens, such as telomeric repeat binding factor 1 (TERF1), as well as established autoantigens, like RuvBL1/2, are associated with telomere and telomerase biology. We aimed to identify new telomere- and telomerase-associated autoantigens in patients with SSc without known autoantibody specificity. METHODS: Unlabelled protein immunoprecipitation combined with gel-free liquid chromatography-tandem mass spectrometry (IP-MS) was performed with sera of 106 patients with SSc from two tertiary referral centres that had a nuclear pattern on HEp-2 indirect immunofluorescence without previously identified autoantibody. Telomere- or telomerase-associated proteins or protein complexes precipitated by individual sera were identified. Candidate autoantigens were confirmed through immunoprecipitation-western blot (IP-WB). A custom Luminex xMAP assay for 5 proteins was evaluated with sera from persons with SSc (n = 467), other systemic autoimmune rheumatic diseases (n = 923), non-rheumatic disease controls (n = 187) and healthy controls (n = 199). RESULTS: Eight telomere- and telomerase-associated autoantigens were identified in a total of 11 index patients, including the THO complex (n = 3, all with interstitial lung disease and two with cardiac involvement), telomeric repeat-binding factor 2 (TERF2, n = 1), homeobox-containing protein 1 (HMBOX1, n = 2), regulator of chromosome condensation 1 (RCC1, n = 1), nucleolar and coiled-body phosphoprotein 1 (NOLC1, n = 1), dyskerin (DKC1, n = 1), probable 28S rRNA (cytosine(4447)-C(5))-methyltransferase (NOP2, n = 1) and nuclear valosin-containing protein-like (NVL, n = 2). A Luminex xMAP assay for THO complex subunit 1 (THOC1), TERF2, NOLC1, NOP2 and NVL revealed high reactivity in all index patients, but also in other patients with SSc and disease controls. However, the reactivity by xMAP assay in these other patients was not confirmed by IP-WB. CONCLUSION: IP-MS revealed key telomere- and telomerase-associated proteins and protein complexes as autoantigens in patients with SSc.

The role of high-resolution manometry in the assessment of upper gastrointestinal involvement in systemic sclerosis: a systematic review.

Systemic sclerosis (SSc) affects the upper gastrointestinal (GI) system in 90% of patients. High-resolution manometry (HRM) assesses esophageal dysmotility, but its role in diagnosis and follow-up remains unclear. The objectives of this systematic review were to investigate the role of HRM in the assessment of SSc-associated upper GI involvement and to evaluate the correlation between HRM abnormalities and clinical characteristics and the effects of therapeutic interventions on HRM findings. Fifteen articles were included. Most (11/15) studies were of very good or good quality. Most studies assessed correlations between esophageal symptoms and esophageal dysmotility. Two studies assessed the effectiveness of buspirone and reported HRM findings. Studies assessing upper GI symptoms using validated questionnaires, such as the University of California Scleroderma Clinical Trial Consortium Gastrointestinal Tract 2.0 or Gastrointestinal Symptoms Severity Index score, found an association between absent contractility on HRM and upper GI symptoms, but even asymptomatic patients often have esophageal body dysmotility on HRM. Esophageal dysmotility positively correlates with the presence of interstitial lung disease on high-resolution computed tomography and reduced diffusion capacity (< 0.8 of predicted value). Trials investigating the effect of buspirone demonstrate both increased lower esophageal sphincter resting pressure and reduced upper GI symptoms. Most studies report on limited patient numbers and retrospective data. Potential bias was minimized using quality appraisal. HRM findings correlate to upper GI symptoms when assessed by validated questionnaires and can detect response to therapy in buspirone trials. Esophageal body dysmotility on HRM positively correlates with the presence of interstitial lung disease. KEY POINTS: • Esophageal body dysmotility on HRM correlates with presence of ILD. • HRM findings seem to correspond to clinical symptom alleviation in interventional trials, but data are still limited. • At present HRM, a procedure with a high negative burden to the patient, offers little to no role in the therapeutic strategy.

Diagnostic Ability of a Dynamic Multidisciplinary Discussion in Interstitial Lung Diseases: A Retrospective Observational Study of 938 Cases.

BACKGROUND: The advice of a dynamic multidisciplinary discussion (MDD) is believed to be important in the diagnosis of interstitial lung diseases (ILDs). However, to what extent MDD diagnoses differ from the preliminary diagnoses before formal workup and MDD (preMDD diagnoses) is still insufficiently studied. METHODS: We compared preMDD and MDD diagnoses in patients discussed at the Leuven University Hospitals MDDs between January 2005 and December 2015. RESULTS: Of 938 consecutive patients discussed in an MDD, 755 (80.5%) received a specific diagnosis. From the 183 patients with unclassifiable ILD, 150 patients (16.0%) received suggestions concerning further investigations to establish a definite diagnosis. In 191 patients (41.9% of patients with a preMDD diagnosis), the MDD changed the diagnosis. In 384 patients (79.5% of patients without preMDD diagnosis), MDD provided a diagnosis when the referring physician did not. MDD diagnosis showed a trend toward better prognostic discrimination between idiopathic pulmonary fibrosis and other ILDs compared with preMDD diagnosis (Harrell C-index, 0.666 vs 0.631; P = .08), which was particularly clear in patients with discordant MDD and preMDD diagnoses (hazard ratio, 2.68 vs 0.84; P = .012 vs .768). CONCLUSIONS: The MDD provided a definite diagnosis in 80.5% of presented cases, suggesting further investigations in almost all others. Given the high number of patients without preMDD diagnosis, the rate of change in preMDD diagnoses (41.9% of patients with a preMDD diagnosis) probably is an underestimation. The better prognostic discrimination among ILDs by using MDD indicates the added value of MDD in ILD.

Illness representations of systemic lupus erythematosus and systemic sclerosis: a comparison of patients, their rheumatologists and their general practitioners.

OBJECTIVE: Discrepancies in illness representations between patients and physicians result in treatment difficulties, decreased well-being of patients and misunderstandings and disrupted communication. Hence, the objective of this study was to compare illness perceptions of individual patients with systemic lupus erythematosus (SLE) and systemic sclerosis (SSc), their rheumatologists and their general practitioners (GPs) and explore potential differences. METHODS: This study has a cross-sectional design. Patients with SLE and SSc, who were followed at the rheumatology department of the University Hospitals Leuven (Belgium), completed the revised Illness Perception Questionnaire which measures patients' perceptions of their condition and captures nine dimensions. Physicians completed the Revised Illness Perception Questionnaire for Healthcare Professionals which consists of seven dimensions and measures perceptions of the healthcare professional regarding the disease of their patients. Intraclass correlation was performed to examine relationships between pairs of respondents; Cohen's d was used for estimating the magnitude of the difference. RESULTS: Questionnaires were sent to 284 patients of whom 241 (113 SSc and 128 SLE patients) were included. Five rheumatologists and 160 GPs participated. For both diseases, positive correlations were found for 'consequences', 'illness coherence' and 'emotional representations' among patients, rheumatologists and GPs. GPs scored higher on the 'consequences' of these diseases for the patient (d=0.71 for SLE; d=0.80 for SSc). Differences between rheumatologists and GPs were small for SSc and moderate to large for 'consequences' (d=0.56) and 'timeline acute/chronic' (d=0.95) in SLE with higher scores for GPs. CONCLUSIONS: For both diseases and among the three groups, significant correlations are detected for the dimensions 'consequences', 'illness coherence' and 'emotional representations'. Differences between rheumatologists and GPs were mainly detected in the case of SLE patients. This can have implications for the collaboration between these two groups of physicians in daily clinical practice. CLINICAL TRIAL REGISTRATION: NCT02655640; Pre-results.

Diverging illness perceptions between physicians about patients with systemic lupus erythematosus and systemic sclerosis: a vignette-based study.

Systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) are complex chronic auto-immune diseases characterized by multiple organ involvement, comorbidities, and complications. This complexity results in a need for a multidisciplinary management and treatment of SLE and SSc by physicians from a number of medical disciplines, all of who may have different perceptions concerning the condition of a particular patient. The aim of this study was to explore differences in physicians' perceptions on the illness of SLE and SSc patients. Physicians from nine disciplines working at three hospitals in Belgium completed illness perception questionnaires for healthcare professionals based on four patient vignettes, i.e., two vignettes per disease (SLE-SSc). Statistical analysis was carried out by a k-means clustering technique for clustering physicians according to their illness perceptions. Fifty physicians, 62% men with a mean age of 42.8 years (SD 11.3) and mean working experience of 12.7 years (SD 11.6), participated. For each disease, three clusters of physicians with different scores in illness perceptions were identified. For SLE, these clusters were specified as the 'optimistic' group, the 'realistic' group, and the 'overwhelming impact by disease' group. For SSc, the clusters were characterized as the 'optimistic' group, the 'realistic' group, and the 'skeptical' group. We found divergent illness perceptions across physicians of the same and other disciplines. Our study yielded three clusters of physicians per disease with a large variability in illness perceptions. Further studies should focus on the factors that determine these differences and their consequences for patient care.