Ultrasound intima-media thickness cut-off values for the diagnosis of giant cell arteritis using a dual clinical and MRI reference standard and cardiovascular risk stratification

Objectives

To derive segmental cut-off values and measures of diagnostic accuracy for the intima-media thickness of compressed temporal artery segments for the diagnosis of giant cell arteritis (GCA) on the patient level. To examine the influence of cardiovascular risk.

Methods

Retrospectively, patients evaluated for GCA with an ultrasound of the temporal arteries and an MRI of the head, including a T1-fatsat-black blood (T1-BB) sequence, were identified and classified based on cardiovascular risk and a dual reference standard of T1-BB on the segmental level and the clinical diagnosis on the patient level. Intima-media thickness of the common superficial temporal artery (CSTA), frontal and parietal branches (FB, PB) were measured by compression technique. Statistically and clinically optimal (specificity of approx. 90% for the patient level) cut-offs were derived. Diagnostic accuracy was evaluated on the patient level.

Results

The population consisted of 144 patients, 74 (51.4%) with and 70 (48.6%) without GCA. The statistically optimal cut-offs were 0.86 mm, 0.68 mm and 0.67 mm for the CSTA, the FB and PB, respectively. On the patient level sensitivity and specificity were 86.5 and 81.4%. Clinically optimal cut-offs were 1.01 mm, 0.82 mm and 0.69 mm and showed a sensitivity of 79.7% and a specificity of 90.0%. For patients without high cardiovascular risk, statistically optimal cut-offs showed a sensitivity of 89.6% and a specificity of 90.5%.

Conclusion

Newly derived ultrasound intima-media thickness cut-offs with a dual reference standard show high diagnostic accuracy on the patient level for the diagnosis of GCA, particularly in patients without high cardiovascular risk.

Patient global assessment and inflammatory markers in patients with idiopathic inflammatory myopathies - A longitudinal study

AIM

To explore if patient global assessment (PGA) is associated with inflammation over time and if associations are explained by other measures of disease activity and function in patients with idiopathic inflammatory myopathies (IIM).

METHODS

PGA and systemic inflammatory markers prospectively collected over five years were retrieved from the International MyoNet registry for 1200 patients with IIM. Associations between PGA, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and creatine kinase (CK) were analyzed using mixed models. Mediation analysis was used to test if the association between PGA and inflammatory markers during the first year of observation could be explained by measures of disease activity and function.

RESULTS

PGA improved, and inflammatory markers decreased during the first year of observation. In the mixed models, high levels of inflammatory markers were associated with worse PGA in both men and women across time points during five years of observation. In men, but not in women, the association between elevated ESR, CRP and poorer PGA was explained by measures of function and disease activity. With a few exceptions, the association between improved PGA and reduced inflammatory markers was partially mediated by improvements in all measures of function and disease activity.

CONCLUSION

Increased levels of systemic inflammation are associated with poorer PGA in patients with IIM. In addition to known benefits of lowered inflammation, these findings emphasize the need to reduce systemic inflammation to improve subjective health in patients with IIM. Furthermore, the results demonstrate the importance of incorporating PGA as an outcome measure in clinical practice and clinical trials.

DWI scrolling artery sign for the diagnosis of giant cell arteritis: a pattern recognition approach

OBJECTIVES

To investigate the diagnostic accuracy of a pattern recognition approach for the evaluation of MRI scans of the head with diffusion-weighted imaging (DWI) in suspected giant cell arteritis (GCA).

METHODS

Retrospectively, 156 patients with suspected GCA were included. The 'DWI-Scrolling-Artery-Sign' (DSAS) was defined as hyperintense DWI signals in the cranial subcutaneous tissue that gives the impression of a blood vessel when scrolling through a stack of images. The DSAS was rated by experts and a novice in four regions (frontotemporal and occipital, bilaterally). The temporal, occipital and posterior auricular arteries were assessed in the T1-weighted black-blood sequence (T1-BB). The diagnostic reference was the clinical diagnosis after ≥6 months of follow-up.

RESULTS

The population consisted of 87 patients with and 69 without GCA; median age was 71 years and 59% were women. The DSAS showed a sensitivity of 73.6% and specificity of 94.2% (experts) and 59.8% and 95.7% (novice), respectively. Agreement between DSAS and T1-BB was 80% for the region level (499/624; kappa(κ)=0.59) and 86.5% for the patient level (135/156; κ=0.73). Inter-reader agreement was 95% (19/20; κ=0.90) for DSAS on the patient level and 91.3% (73/80; κ=0.81) on the region level for experts. For expert versus novice, inter-reader agreement for DSAS was 87.8% on the patient level (137/156; κ=0.75) and 91.2% on the region level (569/624; κ=0.77).

CONCLUSIONS

The DSAS can be assessed in less than 1 min and has a good diagnostic accuracy and reliability for the diagnosis of GCA. The DSAS can be used immediately in clinical practice.

Concomitant Sjögren's disease as a biomarker for treatment effectiveness in rheumatoid arthritis - results from the Swiss clinical quality management cohort

OBJECTIVE

To investigate the clinical phenotype and treatment response in patients with rheumatoid arthritis (RA) with and without concomitant Sjögren's disease (SjD).

METHODS

In this observational cohort study, patients with RA from the Swiss Clinical Quality Management in Rheumatic Diseases registry were categorised according to the presence or absence of SjD. To assess treatment effectiveness, drug retention of tumor necrosis factor-α-inhibitors (TNFi) was compared to other mode of action (OMA) biologics and Janus kinase-inhibitors (JAKi) in RA patients with and without SjD. Adjusted hazard ratios (HR) for time to drug discontinuation were compared in crude and adjusted Cox proportional regression models for potential confounders.

RESULTS

We identified 5974 patients without and 337 patients with concomitant SjD. Patients with SjD were more likely to be female, to have a positive rheumatoid factor, higher disease activity scores, and erosive bone damage. For treatment response, a total of 6781 treatment courses were analysed. After one year, patients with concomitant SjD were less likely to reach DAS28 remission with all three treatment modalities. Patients with concomitant SjD had a higher hazard for stopping TNFi treatment (adjusted HR 1.3 [95% CI 1.07-1.6]; OMA HR 1.12 [0.91-1.37]; JAKi HR 0.97 [0.62-1.53]). When compared to TNFi, patients with concomitant SjD had a significantly lower hazard for stopping treatment with OMA (adjusted HR 0.62 [95% CI 0.46-0.84]) and JAKi (HR 0.52 [0.28-0.96]).

CONCLUSION

RA patients with concomitant SjD reveal a severe RA phenotype, are less responsive to treatment, and more likely to fail TNFi.

Interdisciplinary Diagnosis and Management of Patients with Interstitial Lung Disease and Connective Tissue Disease

Diagnosis of interstitial lung diseases (ILD) can be challenging, and the identification of an associated connective tissue disease (CTD) is crucial to estimate prognosis and establish the optimal treatment approach. Diagnostic delay, limited expertise and fragmented care are barriers that impede the delivery of comprehensive healthcare for patients with rare, complex and multiorgan diseases such as CTD and ILD. In this article we present our perspective on the interdisciplinary diagnosis and interprofessional treatment of patients with ILD and suspected CTD or CTD at risk for ILD. We outline the structure of our service, delineating the roles and responsibilities of the team members. Additionally, we provide an overview of our patient population including diagnostic approaches and specific treatments and illustrate a patient case. Furthermore, we focus on specific benefits and challenges of joint interdisciplinary and interprofessional patient consultations. The importance of rheumatology and pulmonology assessments in specific patient populations is emphasized. Finally, we explore future directions and discuss potential strategies to improve care delivery for patients with CTD-ILD.

Serum protein profiling reveals distinct patient clusters in giant cell arteritis

OBJECTIVES

We investigated the potential of serum proteins to distinguish clinical and molecular subtypes in patients with giant cell arteritis (GCA).

METHODS

Proximity extension assays were used to analyse 1463 proteins in serum samples from patients with new-onset GCA (n = 16) and after achieving remission (n = 13). Unsupervised and supervised cluster analyses were performed.

RESULTS

Unsupervised cluster analysis identified three distinct clusters based on the protein signature. Compared with cluster 2, patients of cluster 1 had less polymyalgia rheumatica symptoms, increased levels of macrophage migration inhibitory factor (MIF) and pronounced NF-kB, STAT5 and interleukin-1 signalling. The changes in serum proteins upon remission differed between cluster 1 and 2.Patients with cranial GCA were characterised by altered endothelial and Th17 signalling whereas patients not responding to treatment within the GUSTO-trial showed increased Th1 and diminished B cell signalling. Patients with anterior ischemic optic neuropathy displayed higher levels of CHI3L1 (YKL40), MMP12 and reduced levels of TIMP3.

CONCLUSIONS

Protein profiling identifies patient clusters in GCA with distinct proteomic features and therefore likely different pathophysiology. These unique proteomic footprints might lead to more targeted treatments in future.

Therapeutic management of fibrosis in systemic sclerosis patients - an analysis from the Swiss EUSTAR cohort

OBJECTIVES

Systemic sclerosis is a chronic autoimmune connective tissue disease leading to microvascular and fibrotic manifestations in multiple organs. Several treatment options and recommendations from different European countries are available. In this study, for which the ambit is Switzerland specifically, we aim to describe the treatment patterns of systemic sclerosis patients with fibrotic manifestations.

METHODS

Systemic sclerosis patients were selected from six Swiss tertiary centres recorded in the multicentre, prospective European Scleroderma Trials and Research (EUSTAR) registry. Patients fulfilling the 2013 ACR/EULAR systemic sclerosis classification criteria at baseline were included. To determine the differences in treatment of varying degrees of fibrosis, four groups were identified: (1) patients with a modified Rodnan skin score (mRSS) >0; (2) those with mRSS ≥7; (3) those with interstitial lung disease (SSc-ILD), diagnosed by either chest X-Ray or high-resolution computed tomography; and (4) patients fulfilling one of the additional criteria for extensive interstitial lung disease, defined as interstitial lung disease involvement of >20% in high-resolution computed tomography, dyspnea NYHA-stage 3/4, or a predicted forced vital capacity (FVC) of <70%.

RESULTS

A total of 590 patients with systemic sclerosis fulfilled the inclusion criteria. In this cohort, 421 (71.4%) had mRSS >0, of whom 195 (33.1%) had mRSS ≥7; interstitial lung disease was diagnosed in 198 of 456 (43.4%), of whom 106 (18.0 %) showed extensive interstitial lung disease. Regarding non-biologic disease-modifying medications (DMARDs), the most frequently prescribed was methotrexate, followed by hydroxychloroquine and mycophenolate mofetil. Rituximab and tocilizumab were most frequently used among the biologic DMARDs. Specifically, 148/372 (39.8%) of treated patients with skin fibrosis received methotrexate, mycophenolate mofetil or rituximab, and 80/177 (45.2%) with interstitial lung disease received cyclophosphamide, mycophenolate mofetil, tocilizumab or rituximab. Most patients received a proton-pump inhibitor, and few patients underwent hematopoietic stem cell transplantation.

CONCLUSION

Overall, in Switzerland, a wide range of medications is prescribed for systemic sclerosis patients. This includes modern, targeted treatments for which randomised controlled clinical trial have been recently reported.

Phenotyping by persistent inflammation in systemic sclerosis associated interstitial lung disease: a EUSTAR database analysis

BACKGROUND

Systemic sclerosis (SSc) is a heterogeneous disease with frequently associated interstitial lung disease (SSc-ILD). We aimed to determine the prognostic potential of phenotyping patients with SSc and SSc-ILD by inflammation and to describe disease trajectories stratified by inflammation and immunosuppressive treatment.

METHODS

Patients from the European Scleroderma Trials and Research (EUSTAR) group cohort were allocated to persistent inflammatory, intermediate and non-inflammatory phenotypes if C-reactive protein (CRP) levels were ≥5 mg/L at ≥80%, at 20-80% and at <20% of visits, respectively. Cox regression models were used to analyse mortality risk and mixed effect models to describe trajectories of FVC and diffusing capacity for carbon monoxide (DLCO) %-predicted stratified by inflammation and immunosuppressive treatment.

RESULTS

2971 patients with SSc and 1171 patients with SSc-ILD had at least three CRP measurements available. Patients with SSc-ILD with a persistent inflammatory phenotype had a 6.7 times higher risk of mortality within 5 years compared with those with a persistent non-inflammatory phenotype (95% CI 3 to 15). In the inflammatory phenotype, FVC %-predicted was declining without (-1.11 (95% CI -2.14 to -0.08)/year), but stable with immunosuppressive treatment (-0.00 (95% CI -0.92 to 0.92)/year). In the non-inflammatory phenotype, patients with and without immunosuppressive treatment had a significant decline in FVC %-predicted, which was more pronounced in those with immunosuppressive treatment (-1.26 (95% CI -1.87 to -0.64) and -0.84 (95% CI -1.35 to -0.33)/year, respectively).

CONCLUSIONS

Phenotyping by persistent inflammation provides valuable prognostic information, independent of demographics, disease duration, cutaneous subtype, treatment and SSc-ILD severity. The findings from this study support early immunosuppressive treatment in patients with SSc-ILD with persistent inflammation.

Comparison of clinical features between patients with anti-synthetase syndrome and dermatomyositis: Results from the MYONET registry

OBJECTIVES

To compare clinical characteristics, including the frequency of cutaneous, extramuscular manifestations, and malignancy, between adults with anti-synthetase syndrome (ASyS) and dermatomyositis (DM).

METHODS

Using data regarding adults from the MYONET registry, a cohort of DM patients with anti-Mi2/-TIF1ɣ/-NXP2/-SAE/-MDA5 autoantibodies, and a cohort of ASyS patients with anti-tRNA synthetase autoantibodies (anti-Jo1/-PL7/-PL12/-OJ/-EJ/-Zo/-KS) were identified. Patients with DM sine dermatitis or with discordant dual autoantibody specificities were excluded. Sub-cohorts of patients with ASyS with or without skin involvement were defined based on presence of DM-type rashes (heliotrope rash, Gottron's papules/sign, violaceous rash, shawl sign, V sign, erythroderma, and/or periorbital rash).

RESULTS

In total 1,054 patients were included (DM, n = 405; ASyS, n = 649). In ASyS cohort, 31% (n = 203) had DM-type skin involvement (ASyS-DMskin). A higher frequency of extramuscular manifestations, including Mechanic's hands, Raynaud's phenomenon, arthritis, interstitial lung disease, and cardiac involvement differentiated ASyS-DMskin from DM (all p< 0.001), whereas higher frequency of any of four DM-type rashes: heliotrope rash (n = 248, 61% vs n = 90, 44%), violaceous rash (n = 166, 41% vs n = 57, 9%), V sign (n = 124, 31% vs n = 28, 4%), and shawl sign (n = 133, 33% vs n = 18, 3%) differentiated DM from ASyS-DMskin (all p< 0.005). Cancer-associated myositis (CAM) was more frequent in DM (n = 67, 17%) compared with ASyS (n = 21, 3%) and ASyS-DMskin (n = 7, 3%) cohorts (both p< 0.001).

CONCLUSION

DM-type rashes are frequent in patients with ASyS; however, distinct clinical manifestations differentiate these patients from classical DM. Skin involvement in ASyS does not necessitate increased malignancy surveillance. These findings will inform future ASyS classification criteria and patient management.

Diffusion-weighted magnetic resonance imaging for the diagnosis of giant cell arteritis - a comparison with T1-weighted black-blood imaging

OBJECTIVES

To investigate the diagnostic performance of diffusion-weighted imaging (DWI) of the superficial cranial arteries in the diagnosis of giant cell arteritis (GCA).

METHODS

Retrospectively, 156 patients with clinically suspected GCA were included. A new 4-point ordinal DWI rating scale was developed. A post-contrast, fat-suppressed, T1-weighted "black-blood" sequence (T1-BB) was rated for comparison. Ten arterial segments were assessed: common superficial temporal arteries, temporal and parietal branches, occipital and posterior auricular arteries bilaterally. The expert clinical diagnosis after ≥ 6 months of follow-up was the diagnostic reference standard. Diagnostic accuracy was evaluated for different rating methods.

RESULTS

The study cohort consisted of 87 patients with and 69 without GCA. For DWI, the area under the curve was 0.90. For a cut-off of ≥ 2 consecutive pathological slices, DWI showed a sensitivity of 75.9%, a specificity of 94.2% and a positive likelihood ratio of 13.09. With a cut-off of ≥ 3 consecutive pathological slices, sensitivity was 70.1%, specificity was 98.6%, and the positive likelihood ratio was 48.38. For the T1-BB, values were 88.5%, 88.4% and 7.63, respectively. The inter-rater analysis for DWI with a cut-off of ≥ 2 pathological slices showed a kappa of 1.00 on the patient level and 0.85 on the arterial segment level. For the T1-BB the kappa was 0.78 and 0.79, respectively.

CONCLUSION

DWI of the superficial cranial arteries demonstrates a good diagnostic accuracy and reliability for the diagnosis of GCA. DWI is widely available and can be used immediately in clinical practice for patients with suspected GCA.

Vision transformer assisting rheumatologists in screening for capillaroscopy changes in systemic sclerosis: an artificial intelligence model

OBJECTIVES

The first objective of this study was to implement and assess the performance and reliability of a vision transformer (ViT)-based deep-learning model, an 'off-the-shelf' artificial intelligence solution, for identifying distinct signs of microangiopathy in nailfold capilloroscopy (NFC) images of patients with SSc. The second objective was to compare the ViT's analysis performance with that of practising rheumatologists.

METHODS

NFC images of patients prospectively enrolled in our European Scleroderma Trials and Research group (EUSTAR) and Very Early Diagnosis of Systemic Sclerosis (VEDOSS) local registries were used. The primary outcome investigated was the ViT's classification performance for identifying disease-associated changes (enlarged capillaries, giant capillaries, capillary loss, microhaemorrhages) and the presence of the scleroderma pattern in these images using a cross-fold validation setting. The secondary outcome involved a comparison of the ViT's performance vs that of rheumatologists on a reliability set, consisting of a subset of 464 NFC images with majority vote-derived ground-truth labels.

RESULTS

We analysed 17 126 NFC images derived from 234 EUSTAR and 55 VEDOSS patients. The ViT had good performance in identifying the various microangiopathic changes in capillaries by NFC [area under the curve (AUC) from 81.8% to 84.5%]. In the reliability set, the rheumatologists reached a higher average accuracy, as well as a better trade-off between sensitivity and specificity compared with the ViT. However, the annotators' performance was variable, and one out of four rheumatologists showed equal or lower classification measures compared with the ViT.

CONCLUSIONS

The ViT is a modern, well-performing and readily available tool for assessing patterns of microangiopathy on NFC images, and it may assist rheumatologists in generating consistent and high-quality NFC reports; however, the final diagnosis of a scleroderma pattern in any individual case needs the judgement of an experienced observer.

Identification of Novel Associations and Localization of Signals in Idiopathic Inflammatory Myopathies Using Genome-Wide Imputation

OBJECTIVE

The idiopathic inflammatory myopathies (IIMs) are heterogeneous diseases thought to be initiated by immune activation in genetically predisposed individuals. We imputed variants from the ImmunoChip array using a large reference panel to fine-map associations and identify novel associations in IIM.

METHODS

We analyzed 2,565 Caucasian IIM patient samples collected through the Myositis Genetics Consortium (MYOGEN) and 10,260 ethnically matched control samples. We imputed 1,648,116 variants from the ImmunoChip array using the Haplotype Reference Consortium panel and conducted association analysis on IIM and clinical and serologic subgroups.

RESULTS

The HLA locus was consistently the most significantly associated region. Four non-HLA regions reached genome-wide significance, SDK2 and LINC00924 (both novel) and STAT4 in the whole IIM cohort, with evidence of independent variants in STAT4, and NAB1 in the polymyositis (PM) subgroup. We also found suggestive evidence of association with loci previously associated with other autoimmune rheumatic diseases (TEC and LTBR). We identified more significant associations than those previously reported in IIM for STAT4 and DGKQ in the total cohort, for NAB1 and FAM167A-BLK loci in PM, and for CCR5 in inclusion body myositis. We found enrichment of variants among DNase I hypersensitivity sites and histone marks associated with active transcription within blood cells.

CONCLUSION

We found novel and strong associations in IIM and PM and localized signals to single genes and immune cell types.

Diffuse myocardial fibrosis precedes subclinical functional myocardial impairment and provides prognostic information in systemic sclerosis

AIMS

Myocardial involvement is common in patients with systemic sclerosis (SSc) and causes myocardial fibrosis and subtle ventricular dysfunction. However, the temporal onset of myocardial involvement during the progression of the disease and its prognostic value are yet unknown. We used cardiovascular magnetic resonance (CMR) to investigate subclinical functional impairment and diffuse myocardial fibrosis in patients with very early diagnosis of SSc (VEDOSS) and established SSc and examined whether this was associated with mortality.

METHODS AND RESULTS

One hundred and ten SSc patients (86 established SSc, 24 VEDOSS) and 15 healthy controls were prospectively recruited. The patients were followed-up for a median duration of 7.0 years (interquartile range 6.0-7.3 years). Study subjects underwent CMR including assessment of myocardial fibrosis [native T1 and extracellular volume (ECV)] and measurement of global longitudinal (GLS) and circumferential (GCS) myocardial strain. Native T1 values and ECV were elevated in VEDOSS and SSc patients compared with controls (P < 0.001). GLS was similar in VEDOSS and controls but significantly impaired in patients with established SSc (P < 0.001). GCS was similar over all groups (P = 0.88). There were 12 deaths during follow-up. Elevated native T1 [hazard ratio (HR) 5.8, 95% confidence interval (CI): 1.7-20.4; P = 0.006] and reduced GLS (HR 6.1, 95% CI: 1.3-29.9; P = 0.038) identified subjects with increased risk of death. Only native T1 was predictive for cardiovascular mortality (P < 0.001).

CONCLUSION

Subclinical myocardial involvement first manifests as diffuse myocardial fibrosis identified by the expansion of ECV and increased native T1 in VEDOSS patients while subtle functional impairment only occurs in established SSc. Native T1 and GLS have prognostic value for all-cause mortality in SSc patients.

Belimumab treatment in autoimmune hepatitis and primary biliary cholangitis - a case series

Background

The majority of patients with autoimmune hepatitis (AIH) achieve complete remission with established treatment regiments. In patients with intolerance or insufficient response to these drugs, the remaining options are limited and novel treatment approaches necessary. In primary biliary cholangitis (PBC), ursodeoxycholic acid (UDCA) and fibrates have improved prognosis dramatically, but there remains a proportion of patients with refractory disease.In patients with refractory AIH and/or PBC, we used a novel treatment strategy with the anti-B cell activating factor, belimumab. The first three patients had concomitant Sjögren's disease. The connecting element between all three diseases is B cell activation, including elevated levels of the B cell activating factor (BAFF). Furthermore, belimumab has been shown to be beneficial in Sjögren's disease.

Aims and methods

To retrospectively investigate treatment response in six patients with AIH or PBC with or without concomitant Sjögren's disease treated with the anti-BAFF therapy belimumab at the University Hospital in Bern, Switzerland.

Results

In all three patients with AIH, belimumab improved disease control and helped by-pass or reduce problematic side effects from corticosteroids and calcineurin inhibitors. In PBC patients (n = 3), there was no clear improvement of liver function tests, despite reduction or normalization of IgM. All patients with concomitant Sjögren's disease (n = 3) had an improvement of sicca symptoms and two out of three patients experienced an initially marked reduction in fatigue, which lessened over time.

Conclusions

Belimumab may be a promising treatment option for patients with AIH and further investigations are needed. In PBC however, response was not convincing. The effects on sicca symptoms and fatigue were encouraging.

Transferability of radiomic signatures from experimental to human interstitial lung disease

Background

Interstitial lung disease (ILD) defines a group of parenchymal lung disorders, characterized by fibrosis as their common final pathophysiological stage. To improve diagnosis and treatment of ILD, there is a need for repetitive non-invasive characterization of lung tissue by quantitative parameters. In this study, we investigated whether CT image patterns found in mice with bleomycin induced lung fibrosis can be translated as prognostic factors to human patients diagnosed with ILD.

Methods

Bleomycin was used to induce lung fibrosis in mice (n_control = 36, n_experimental = 55). The patient cohort consisted of 98 systemic sclerosis (SSc) patients (n_ILD = 65). Radiomic features (n_histogram = 17, n_texture = 137) were extracted from microCT (mice) and HRCT (patients) images. Predictive performance of the models was evaluated with the area under the receiver-operating characteristic curve (AUC). First, predictive performance of individual features was examined and compared between murine and patient data sets. Second, multivariate models predicting ILD were trained on murine data and tested on patient data. Additionally, the models were reoptimized on patient data to reduce the influence of the domain shift on the performance scores.

Results

Predictive power of individual features in terms of AUC was highly correlated between mice and patients (r = 0.86). A model based only on mean image intensity in the lung scored AUC = 0.921 ± 0.048 in mice and AUC = 0.774 (CI95% 0.677-0.859) in patients. The best radiomic model based on three radiomic features scored AUC = 0.994 ± 0.013 in mice and validated with AUC = 0.832 (CI95% 0.745-0.907) in patients. However, reoptimization of the model weights in the patient cohort allowed to increase the model’s performance to AUC = 0.912 ± 0.058.

Conclusion

Radiomic signatures of experimental ILD derived from microCT scans translated to HRCT of humans with SSc-ILD. We showed that the experimental model of BLM-induced ILD is a promising system to test radiomic models for later application and validation in human cohorts.

Sekundäre Immundefekte in der Rheumatologie

Zusammenfassung. Bei der Behandlung von autoimmunen und autoinflammatorischen Erkrankungen spielt die immunsuppressive Behandlung mit konventionellen, «Small Molecule»- oder biologischen Basistherapeutika eine entscheidende Rolle. Dies kann zu einer sekundären Immundefizienz mit erhöhtem Risiko für Infektionen führen, worauf wir in diesem Artikel eingehen. Das Reaktivierungsrisiko bei chronischer Hepatitis B ist besonders hoch bei Glukokortikoidsteroid-Dosen ≥ 20mg/d für länger als vier Wochen, bei B-Zell-depletierenden Therapien, gefolgt von Anti-TNF-α-Inhibitoren. Letztere gehen zudem mit einem hohen Reaktivierungsrisiko einer latenten Tuberkulose einher. Hohe Glukokortikosteroid-Dosen über längere Zeiträume stellen einen Risikofaktor für Pneumonie mit Pneumocystis jirovecii dar, insbesondere in der Kombination mit weiteren Basistherapeutika. Ein gesteigertes Risiko für Herpes zoster besteht vor allem bei TNF-α-Inhibition sowie bei JAK-Inhibitoren. Eine schwere Immunsuppression (z.B. B-Zell-Depletion, Cyclophosphamid, Mycophenolate Mofetil, JAK-Inhibitoren, Prednisondosen ≥ 20mg/d oder auch Kombinationstherapien) erhöht das Risiko für einen schweren Krankheitsverlauf mit COVID-19.

Skeletal Muscle Disorders: A Noncardiac Source of Cardiac Troponin T

BACKGROUND

Cardiac troponin (cTn) T and cTnI are considered cardiac specific and equivalent in the diagnosis of acute myocardial infarction. Previous studies suggested rare skeletal myopathies as a noncardiac source of cTnT. We aimed to confirm the reliability/cardiac specificity of cTnT in patients with various skeletal muscle disorders (SMDs).

METHODS

We prospectively enrolled patients presenting with muscular complaints (≥2 weeks) for elective evaluation in 4 hospitals in 2 countries. After a cardiac workup, patients were adjudicated into 3 predefined cardiac disease categories. Concentrations of cTnT/I and resulting cTnT/I mismatches were assessed with high-sensitivity (hs-) cTnT (hs-cTnT-Elecsys) and 3 hs-cTnI assays (hs-cTnI-Architect, hs-cTnI-Access, hs-cTnI-Vista) and compared with those of control subjects without SMD presenting with adjudicated noncardiac chest pain to the emergency department (n=3508; mean age, 55 years; 37% female). In patients with available skeletal muscle biopsies, TNNT/I1-3 mRNA differential gene expression was compared with biopsies obtained in control subjects without SMD.

RESULTS

Among 211 patients (mean age, 57 years; 42% female), 108 (51%) were adjudicated to having no cardiac disease, 44 (21%) to having mild disease, and 59 (28%) to having severe cardiac disease. hs-cTnT/I concentrations significantly increased from patients with no to those with mild and severe cardiac disease for all assays (all P<0.001). hs-cTnT-Elecsys concentrations were significantly higher in patients with SMD versus control subjects (median, 16 ng/L [interquartile range (IQR), 7-32.5 ng/L] versus 5 ng/L [IQR, 3-9 ng/L]; P<0.001), whereas hs-cTnI concentrations were mostly similar (hs-cTnI-Architect, 2.5 ng/L [IQR, 1.2-6.2 ng/L] versus 2.9 ng/L [IQR, 1.8-5.0 ng/L]; hs-cTnI-Access, 3.3 ng/L [IQR, 2.4-6.1 ng/L] versus 2.7 ng/L [IQR, 1.6-5.0 ng/L]; and hs-cTnI-Vista, 7.4 ng/L [IQR, 5.2-13.4 ng/L] versus 7.5 ng/L [IQR, 6-10 ng/L]). hs-cTnT-Elecsys concentrations were above the upper limit of normal in 55% of patients with SMD versus 13% of control subjects (P<0.01). mRNA analyses in skeletal muscle biopsies (n=33), mostly (n=24) from individuals with noninflammatory myopathy and myositis, showed 8-fold upregulation of TNNT2, encoding cTnT (but none for TNNI3, encoding cTnI) versus control subjects (n=16, P_Wald<0.001); the expression correlated with pathological disease activity (R=0.59, P_t-statistic<0.001) and circulating hs-cTnT concentrations (R=0.26, P_t-statistic=0.031).

CONCLUSIONS

In patients with active chronic SMD, elevations in cTnT concentrations are common and not attributable to cardiac disease in the majority. This was not observed for cTnI and may be explained in part by re-expression of cTnT in skeletal muscle.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03660969.

POS0873 PERSISTENT INFLAMMATION IN SYSTEMIC SCLEROSIS IS STRONGLY ASSOCIATED WITH SEVERE DISEASE AND MORTALITY: AN ANALYSIS FROM THE EUSTAR DATABASE

Background

Systemic sclerosis (SSc) is a heterogeneous autoimmune disease, with a high disease-related mortality and morbidity. A subset of patients show elevated CRP levels (20-35%), which has been reported as inflammatory SSc. Preliminary data suggest that this subset is characterized by a severe phenotype.

Objectives

To analyse the phenotype and the survival of inflammatory compared with non-inflammatory SSc patient subsets.

Methods

Data from 8571 SSc patients with available CRP measurement from the EUSTAR cohort were analysed. Exclusion criteria included acute infection, missing follow-up and tocilizumab treatment. Patients with a CRP ≥5mg/l at ≥80% of visits were stratified as persistent inflammatory and as non-inflammatory if CRP was ≥5 mg/l at <20% of visits (as described previously (1)). As a sensitivity analysis, patients were defined as inflammatory and non-inflammatory based on a single CRP measurement at baseline only (CRP ≥5 or <5mg/l, respectively). We compared baseline characteristics using Chi-square and non-parametric Kruskal–Wallis tests as appropriate. Kaplan Meier curves with log-rank tests were used to estimate time from baseline to death or censoring, and Cox regression to compare mortality risks adjusted for time from diagnosis to baseline.

Results

Out of 2883 patients with more than two visits, 404 (14%) showed persistent inflammation and 1032 (36%) a non-inflammatory phenotype. Out of 5619 patients with more than one visit, 1830 (33%) were stratified as inflammatory as defined by as single CRP measurement at baseline and 3789 (67%) as non-inflammatory. With both definitions, the inflammatory subset revealed a more severe phenotype than non-inflammatory patients, including more frequent diffuse-cutaneous disease, anti-Scl-70 autoantibodies, pulmonary fibrosis, pulmonary hypertension, higher modified Rodnan skin score, and lower forced vital capacity and diffusing capacity for carbon monoxide. Patients with persistent inflammation had a strongly increased risk of all-cause mortality (HR 7.1 [95%CI 3.7 to 13.5], p<0.001) compared to non-inflammatory patients, whereas this association was weaker when based on a single CRP measurement (HR 2.6 [95%CI 2.1 to 3.2], p<0.001).

Conclusion

The severe phenotype and decreased survival of the inflammatory SSc subset, which was most prominent in patients with persistently elevated CRP levels, suggest a distinct disease subset. Therefore both, the need for more regular monitoring of inflammatory parameters and implications for immune-modulating treatment, needs to be carefully analysed.

References

[1]Mitev, A., et al., Inflammatory stays inflammatory: a subgroup of systemic sclerosis characterized by high morbidity and inflammatory resistance to cyclophosphamide. Arthritis Res Ther, 2019. 21(1): p. 262. PMID: 31791379

Figure 1.

Overall mortality from baseline onward a. by persistent inflammatory phenotype, b. by inflammatory phenotype at baseline

Disclosure of Interests

Adela-Cristina Sarbu: None declared, Sabina Guler: None declared, Odile Stadler: None declared, Yannick Allanore: None declared, Vera Bernardino: None declared, Jörg H.W. Distler: None declared, Armando Gabrielli: None declared, Anna-Maria Hoffmann-Vold: None declared, Marco Matucci-Cerinic: None declared, Ulf Müller-Ladner: None declared, Vera Ortiz-Santamaria: None declared, Simona Rednic: None declared, Valeria Riccieri: None declared, Vanessa Smith: None declared, Susanne Ullman: None declared, Ulrich Walker: None declared, Thomas Geiser: None declared, Oliver Distler: None declared, Britta Maurer Speakers bureau: Boehringer-Ingelheim, Consultant of: Novartis, Boehringer Ingelheim, Janssen-Cilag, Grant/research support from: AbbVie, Protagen, Novartis Biomedical Research, Florian Kollert Shareholder of: Roche, Consultant of: BMS, Actelion, Boehringer-Ingelheim, Pfizer, Grant/research support from: Roche, Gilead, Pfizer, Employee of: Roche

OP0199 RADIOMIC SIGNATURES REFLECT TREATMENT RESPONSE TO NINTEDANIB IN PRECLINICAL LUNG FIBROSIS MODEL

Background

Responses to anti-fibrotic drugs in preclinical disease models are difficult to quantify by histological analysis of single tissue sections. Quantitative in-depth analysis of imaging data, termed “radiomics”, may represent a more reliable and accurate measure of treatment response since the pathology of the whole organ is captured.

Objectives

To study the potential of µCT-derived radiomic features to reflect response to Nintedanib in the bleomycin (BLM)-induced murine model of fibrosing interstitial lung disease.

Methods

All C57BL/6J mice from both study groups were intratracheally instilled with 2 U/kg BLM on day 0 to induce lung fibrosis. Nintedanib was administered daily by gavage at 60 mg/kg for two weeks starting from day 7 (n=15). Controls received equivalent treatment with vehicle-only (n=19). Whole lung µCT scans (SkyScan 1176, Bruker) of each animal were acquired at baseline (day 0), pre-treatment (day 7), and post-treatment (day 21). The Ashcroft score was assessed on Sirius Red stained lung sections post-treatment. Lung volumes in µCTs were defined semi-automatically in MIM Software (6.9.2), followed by extraction of radiomic features with our in-house developed software Z-Rad (7.3.1). Each data set contained 1’386 features, describing image characteristics with histogram, texture, and wavelet functions. Data pre-processing involved removal of features sensitive to intra- and interobserver delineation variability (ICC<0.75), highly correlated features (Pearson’s r>0.95), and features not significantly changing between days 0 and 7 (p>0.05). Agglomerative clustering of radiomic temporal trajectories was performed on the Nintedanib group to identify distinct feature clusters. The identified feature sets were then used to plot average feature value trajectories for both study groups in each cluster. To identify features significantly different between a) Nintedanib vs. control, and b) pre- vs. post-treatment, Mann-Whitney U and Wilcoxon signed-rank tests were used, respectively. Samples were pooled from two independent experiments.

Results

Evaluation of tissue sections did not show a significant treatment-induced reduction of fibrosis with average Ashcroft scores of 3.7 (±1.2 s.d.) and 3.4 (±1.6 s.d.) in Nintedanib and control samples, respectively (p>0.05). Radiomics data analysis revealed two feature clusters in Nintedanib samples, composed of 52 features (cluster 1) and 96 features (cluster 2), the trajectories of which were then plotted for both study groups. In cluster 1, feature value trajectories significantly decreased in both Nintedanib and control group between pre-and post-treatment (p<0.001), whereas feature values in cluster 2 remained flat (p>0.05). Importantly, Nintedanib-treated mice displayed a much more pronounced feature value decrease post-treatment in cluster 1 compared to the control group (p<0.05). Here, feature values post-treatment resembled pre-disease baseline conditions in the Nintedanib group (p>0.05), whereas the control group remained significantly different from baseline (p<0.01). Cluster 1 was composed of 6 histogram, 11 texture, and 35 wavelet features, emphasizing the role of high-dimensional metrics for the detection of differences.

Conclusion

Histological quantification of lung fibrosis accounts only for a small fraction of the whole pathology in a spatially heterogeneous disease. We demonstrated that µCT-derived radiomic features identified significant differences on imaging level following Nintedanib treatment, which we could not reliably detect on tissue level using Ashcroft scoring. These findings hold great potential for the development of novel readouts for improved stratification of anti-fibrotic treatment effects in preclinical models.

Acknowledgements

This study received funding support from the Swiss Lung Association.

Disclosure of Interests

David Lauer Shareholder of: Roche (no relation to project), Employee of: Former employee of Roche (no relation to project), Janine Schniering: None declared, Hubert Gabrys: None declared, Malgorzata Maciukiewicz: None declared, Matthias Brunner: None declared, Oliver Distler Speakers bureau: Speaker fees in the area of systemic sclerosis and related complications from Bayer, Boehringer Ingelheim, Janssen, Medscape, Consultant of: Consultancies in the area of systemic sclerosis and its complications with Abbvie, Acceleron, Alcimed, Amgen, AnaMar, Arxx, AstraZeneca, Baecon, Blade, Bayer, Boehringer Ingelheim, Corbus, CSL Behring, 4P Science, Galapagos, Glenmark, Horizon, Inventiva, Kymera, Lupin, Miltenyi Biotec, Mitsubishi Tanabe, MSD, Novartis, Prometheus, Roivant, Sanofi and Topadur, Grant/research support from: Grant/research support from Kymera, Mitsubishi Tanabe, Boehringer Ingelheim, Thomas Frauenfelder: None declared, Stephanie Tanadini-Lang: None declared, Britta Maurer Speakers bureau: Received speaker fees from Boehringer-Ingelheim as well as congress support from Medtalk, Pfizer, Roche, Actelion, Mepha, and MSD, Consultant of: Consultancies with Novartis, Boehringer Ingelheim, Janssen-Cilag. Has a patent mir-29 for the treatment of systemic sclerosis issued (US8247389, EP2331143), Grant/research support from: Had grant/research support from AbbVie, Protagen, Novartis Biomedical Research.

POS0406 CHARACTERISATION OF ENHANCER RNAs IN RHEUMATOID ARTHRITIS SYNOVIAL FIBROBLASTS

Background

Rheumatoid arthritis synovial fibroblasts (SF) exhibit a prolonged histone 3 lysine 27 acetylation (H3K27ac) after stimulation with TNF, leading to a sustained inflammatory response. Enhancer RNAs (eRNAs) are short-lived non-coding RNAs transcribed from cell type-specific H3K27ac-marked enhancers that facilitate the transcription of their linked coding genes. The interrelation of eRNAs and their linked coding genes in SF has not been studied yet.

Objectives

To analyze the expression and regulation of inflammatory eRNAs in SF.

Methods

The expression of eRNAs in SF (n=9), stimulated with TNF (24h; 10 ng/µl) or left untreated, was detected by cap analysis of gene expression followed by sequencing (CAGEseq). To further investigate eRNA expression in SF, the expression of selected eRNAs and their linked coding genes (CXCL1, CCL20, IL6, CCL2, CXCL12, IL8) was analyzed by real-time PCR in SF that were stimulated with TNF (1, 3, 6, 24h; 10 ng/µl), IL1 (1, 24h; 1 ng/ml), or the Toll-like receptor agonists Pam3 (1, 24h; 1 ng/ml), pIC (1, 24h; 10 μg/ml) and LPS (1, 24h; 100 ng/µl). Samples containing the untranscribed RNA were measured in parallel. To study eRNA regulation, SF were treated with the bromodomain inhibitor I-BET (1 µM; 24h), or silenced for the histone acetyltransferases CBP and p300 by transfection of antisense LNA gapmeRs (12.5 nM) prior to stimulation with TNF (1, 24h).

Results

We have selected four potential eRNAs for CCL2 and IL8, three for CXCL12, two for IL6 and CXCL1 and one for CCL20 from CAGEseq analysis. They were located upstream (eCCL2#1, eCCL2#2, eCXCL1#2, eCXL12#3, eIL6#1 + 2, eIL8#1-4), downstream (eCCL2#3, eCCL2#4, eCXCL1#1, eCXL12#1) and intronic (eCCL20, eCXL12#2) at distances between 300 bp to 35.6 kb relative to the transcription start sites of the corresponding coding genes. None of the eRNAs was present in all nine samples in CAGEseq data sets, indicating a patient-dependent variability in eRNA expression. The majority of eRNAs were not detected in unstimulated SF, with the exception of eRNAs for CXCL12. By performing TNF time course experiments (Figure 1), we have detected different patterns of eRNAs: (a) eRNAs, that peaked at 1h (eCCL20, eIL8#2, eCCL2#1), (b) at 6h (eCXCL1#1), (c) or at 24h (eIL8#1, eIL8#3, eIL8#4, eCXCL1#2) after stimulation, (d) eRNAs that were stably expressed over the time points (eCCL2#2, 3, 4), and (e) eRNAs that were down regulated by TNF stimulation (eCXCL12#1, eCXCL12#3). All inflammatory stimuli induced eRNA expression in SF, with LPS and IL1, followed by TNF, being the most potent inducers of eRNAs. I-BET suppressed the TNF-induced expression of all eRNAs tested. The effects on the expression of eRNAs after silencing of p300 but not of CBP mirrored to a large extent those of the respective coding genes.

Figure 1.

Conclusion

In SF, the expression of some eRNAs is maintained for up to 24h, contradicting previous reports that eRNAs are short-lived. Our data suggest that different eRNAs orchestrate the early and sustained expression of cytokines and chemokines in SF. eRNA expression is controlled by p300 and BET bromodomain proteins.

Disclosure of Interests

Larissa Moser: None declared, Miranda Houtman: None declared, Oliver Distler Consultant of: Abbvie, Britta Maurer Speakers bureau: Boehringer-Ingelheim, Consultant of: Novartis, Boehringer Ingelheim, Janssen-Cilag, Grant/research support from: AbbVie, Protagen, Novartis Biomedical Research, Caroline Ospelt: None declared, Kerstin Klein Grant/research support from: Novartis Foundation for biomedical research (2019)

POS0892 IDENTIFICATION OF DEFINED MICROANGIOPATHIC CHANGES IN NAILFOLD CAPILLAROSCOPY IMAGES OF PATIENTS WITH SYSTEMIC SCLEROSIS USING A VISION TRANSFORMER MODEL – A MONOCENTRIC IMPLEMENTATION AND VALIDATION COHORT STUDY

Background

An accurate assessment of nailfold capillaroscopy (NFC) images has great importance in the diagnosis and prognosis of systemic sclerosis (SSc). To overcome some of the inherent problems with NFC image analysis (operator/observer bias, time requirements), there is an interest to automate and standardize NFC image assessment using computer vision algorithms, such as the Vision Transformer (ViT), which are based on recent advances in deep learning.

Objectives

Our aims were (1) to implement and assess the performance and the reliability of ViT in detecting changes on NFC images, and (2) to compare the performance of ViT to that of practicing rheumatologists.

Methods

For this study, we used NFC images of patients with SSc enrolled in our European Scleroderma Trials and Research group (EUSTAR) and Very Early Diagnosis of Systemic Sclerosis (VEDOSS) local registries. Concretely, we included routine NFC images (all NFC images available – digit II to V of both hands-, irrespective of any image artefacts) of patients aged ≥ 18 years with visits between 2012 and 2021, who fulfilled either the 2013 American College of Rheumatology / European League Against Rheumatism classification criteria for SSc (established disease) or the preliminary criteria for VEDOSS (mild/early disease).

ViT was trained to identify the following NFC signs of microangiopathy: enlarged capillaries (apex diameter of the capillary > 20 µm, and < 50µm), giant capillaries (> 50 µm), loss of capillaries (< 7 capillaries/mm), and microhaemorrhages. Absence of any of these signs was considered as being a “normal NFC”, while presence of any of these signs was seen as an abnormal NFC image. Its performance was evaluated in a cross-fold (k = 5) validation setting, and the gold standard was the treating physician. Area under the ROC curve (AUC) was used as indicator of the performance. Considered cut-offs for AUC were 90-100% - excellent, 80-89.9% - good, 70-79.9% - fair, 60-69.9% - poor, 50-59.9% - fail. From the first cross-fold, a randomly sampled reliability set was created which was used to compare the NFC assessment performance of four rheumatologists (three invited and trained annotators and the treating physician) with that of of ViT.

Results

We analysed 17,126 NFC images of 234 EUSTAR patients (14.6% males, 67.8% limited cutaneous SSc, median age 57 years, median disease duration 9 years) and 55 VEDOSS patients (92.7% females, median age 44 years, median time elapsed since first Raynaud’s phenomenon 5 years). ViT had fair to excellent performance in identifying the different NFC changes across all five folds (of 3443 NFC images each), with an area under the ROC curve ranging from 78.59% to 90.4% (Figure 1a).

Figure 1.

Performance of the ViT: (a) AUCs values for ViT in diagnosing the respective feature on NFC image. (b) Sensitivity / specificity trade-off across the images in the reliability set. The blue lines show the ROC curves corresponding to the ViT predictions, with ViT’s AUC, “optimal” sensitivity and specificity shown in the box. Also shown are the point performances of each of the four annotators, with performances below the blue line indicating lower performance than ViT.

In the reliability set (see Figure 1b), we observed highest performance for diagnosing giant capillaries (AUC =92.89%) followed by identification of enlarged capillaries (AUC = 91.7%). Good AUCs were seen in depicting capillary loss (AUC = 87.3%), microhemorrhages (AUC = 85.9%) and the abnormal/normal NFC classification (AUC = 84.7%). The rheumatologists had generally higher performance in assessing NFC images. However, ViT outperformed two rheumatologists with different experience in classifying capillary loss and enlarged capillaries, respectively.

Conclusion

ViT is a modern, well performing and readily available AI model to assess signs of microangiopathy on NFC images acquired during routine practice.

Disclosure of Interests

Alexandru Garaiman: None declared, Farhad Nooralahzadeh: None declared, Carina Mihai Speakers bureau: MEDtalks Switzerland, Mepha, Nikitas Gkikopoulos: None declared, Nicolas Perez Gonzalez: None declared, Mike O. Becker Speakers bureau: Mepha, MSD, Novartis, GSK, Bayer and Vifor, Oliver Distler Speakers bureau: Bayer, Boehringer Ingelheim, Medscape, Novartis, Roche, Pfizer, Roche, Sanofi, Consultant of: Abbvie, Acceleron, Alcimed, Amgen, AnaMar, Arxx, AstraZeneca, Baecon, Blade, Bayer, Boehringer Ingelheim, ChemomAb, Corbus, CSL Behring, Galapagos, Glenmark, GSK, Horizon, Inventiva, iQvia, Kymera, Lupin, Medac, Medscape, Miltenyi Biotec, Mitsubishi Tanabe, MSD, Prometheus Biosences, Roche, Roivant, Topadur and UBC, Lilly, Pfizer, Grant/research support from: Kymera, Mitsubishi Tanabe, Michael Krauthammer Speakers bureau: Oncobit, Britta Maurer Speakers bureau: Boehringer-Ingelheim, Medtalk, Pfizer, Roche, Actelion, Mepha, and MSD, Consultant of: Novartis, Boehringer Ingelheim, Janssen-Cilag, Grant/research support from: AbbVie, Protagen, Novartis Biomedical Research

POS0426 BRD3 REGULATES THE INFLAMMATORY AND STRESS RESPONSE IN RHEUMATOID ARTHRITIS SYNOVIAL FIBROBLASTS

Background

Small molecule inhibitors targeting members of the bromodomain and extra-terminal (BET) protein family (BRD2, BRD3, BRD4) have anti-inflammatory properties in rheumatoid arthritis (RA). BET proteins are readers of acetylated histone side chains and activators of transcription. BRD3 is an understudied member of BET proteins.

Objectives

To analyse individual functions of BET proteins and mechanisms underlying BET inhibition in RA synovial fibroblasts (SF).

Methods

The expression of BRD2, BRD3, and BRD4 was silenced by lenti-viral transduction followed by TNF stimulation (10 ng/µl, 24h). Silencing was confirmed by Western blotting. Transcriptomes were determined by RNA-seq (Illumina NovaSeq 6000, n=3). Pathway enrichment analysis for KEGG and Reactome databases was conducted with significantly affected genes (± fold change > 1.5, FDR < 0.05). SF were treated with I-BET (1 µM) and TNF (10 ng/µl, 24h). Autophagy was evaluated by Western blotting using the conversion of LC3B as a marker (n=9). I-BET-induced global changes on post-translational histone modifications were analysed by mass spectrometry (Mod Spec, Active Motif; n=2; 120h protocol) and Western blotting (H3K27ac, H3K18ac, total acH3; n=7; 24h and 120h protocol). For this purpose, SF were stimulated with I-BET (1 µM) for 24h, and either co-stimulated with TNF (24h protocol), or washed with PBS, followed by a 24h stimulation with TNF 120h after the I-BET treatment (120h protocol).

Results

Silencing of BRD2 and BRD4 in SF was, in contrast to silencing of BRD3, associated with high levels of cell death, and therefore not analyzed further. We detected 257 and 324 differentially expressed genes (DEG) that were affected by BRD3 silencing in unstimulated and TNF-stimulated SF, respectively. 105 DEG overlapped between the two groups. DEG were enriched in inflammatory pathways such as “TNF signaling pathway”, “rheumatoid arthritis”, “Toll-like receptor cascades”, “MAPK signaling pathway”, “IL-17 signaling pathway” and “signaling by interleukins”. Furthermore, pathway enrichment analysis suggested a role for BRD3 in different stress-associated pathways, including “DNA repair”, “chaperone mediated autophagy”, “cellular responses to stress”, and “autophagy”. In line with the pathway enrichment analysis, I-BET induced levels of LC3B-II in unstimulated (4.3 fold, p=0.07) and TNF-stimulated (2.9 fold, p=0.07) SF, indicating a role of BET proteins in the regulation of autophagy. To further study the mechanisms underlying I-BET-mediated suppression of gene expression, we analyzed potential effects of I-BET on histone modifications. Mod Spec analysis indicated that I-BET induced profound changes in chromatin modifications, with a global reduction of acetylation on different histone side chains. We confirmed some of these differences in independent samples. I-BET treatment reduced mean TNF-induced levels of total acH3 by 25.2% (120h; p=0.0303), of H3K18ac by 35.3% (24h; p=0.0288) and by 29.3% (120h; p=0.0373) and of H3K27ac by 41.7% (120h; p=0.0587).

Conclusion

BRD3 acts as an upstream regulatory factor that integrates the response to inflammatory stimuli and stress conditions in SF. Our data suggest that BET inhibitors do not only prevent the reading of acetylated histone side chains, but also directly affect the chromatin structure, in particular by downregulating global levels of histone acetylation.

Disclosure of Interests

Malgorzata Maciukiewicz: None declared, Larissa Moser: None declared, Monika Krosel: None declared, Tanja Seifritz: None declared, Matija Tomsic: None declared, Britta Maurer Speakers bureau: Boehringer-Ingelheim, Consultant of: Novartis, Boehringer Ingelheim, Janssen-Cilag, Grant/research support from: AbbVie, Protagen, Novartis Biomedical Research, Oliver Distler Consultant of: Abbvie, Caroline Ospelt: None declared, Kerstin Klein Grant/research support from: Novartis Foundation for biomedical research (2019)

[Dermatomyositis and juvenile dermatomyositis]

Dermatomyositis (DM) is an inflammatory multisystem disease of unknown etiology, which can already occur in children but first onset can also be in older adulthood. Myalgia and muscle weakness can occur later in the course of the disease or even be completely absent in some forms. Classical signs on the skin include heliotrope rash, facial erythema, Gottron's papules and nailfold capillary abnormalities. For the diagnosis, screening for the presence of myositis-specific autoantibodies has become increasingly more relevant. Muscle enzymes may be elevated but not in approximately one third of patients. In the absence of typical clinical or serologic findings, additional examination methods such as nailfold capillaroscopy, magnetic resonance imaging, electromyography, skin or muscle biopsies may help to establish the diagnosis. Depending on the clinical and serological subtype, additional screening for gastrointestinal or cardiopulmonary involvement should be considered. In adults, an age-appropriate tumor screening should also be performed. Apart from corticosteroids as induction therapy, biologics and small molecule inhibitors are gaining in importance in addition to conventional disease-modifying anti-rheumatic drugs and intravenous immunoglobulins. The prognosis for DM and juvenile DM (JDM) has improved. Most patients recover at least to some extent; however, a few patients die and a minority develop persisting muscle atrophy or severe calcinosis.

P222 Clinical features of extra-muscular disease in dermatomyositis and anti-synthetase syndrome patients with skin involvement classified by presence of disease-specific autoantibodies: results from the EuroMyositis registry

Background/Aims

Anti-synthetase syndrome (ASS) represents a distinct entity within myositis spectrum disorders; however, correct classification of patients with anti-tRNA synthetase autoantibodies and skin manifestations akin to dermatomyositis (DM) remains uncertain. Our aim was to compare clinical characteristics, skin involvement, and malignancy, between patients with ASS and DM, classified by disease-specific autoantibodies.

Methods

Data from 05/2009-03/2016 from 9 countries from the prospective, myositis EuroMyositis registry were downloaded. Those with anti-tRNA synthetase autoantibodies (Jo-1/PL-7/PL-12/OJ/EJ/KS) were classified as ASS, and those with Mi-2/TIF1-γ/NXP2/SAE/MDA5 autoantibodies as DM. Clinical phenotypes including malignancies (except skin malignancies) were tabulated. Characteristics of patients with skin involvement (excluding mechanic’s hands and Raynaud’s phenomenon) were compared using Fisher’s exact test with Bonferroni corrected p-values.

Results

Of 3,067 patients, 2,028 had autoantibody profiling results (66.1%), of which 783 (38.6%) were positive for at least one of the autoantibodies being considered. Five patients with dual autoantibody specificities were excluded. Of the remaining 778, 320 (41.1%) were classified as DM, and 458 (58.9%) as ASS. Median age at diagnosis was 48.2 years (interquartile range [IQR] 37.5 to 57.8) in the DM cohort and 49 (IQR 38.3 to 62.2) in the ASS cohort. Skin involvement was present in 277 (86.6%) DM patients (DM skin) vs 204 (44.5%) ASS patients (ASS skin) (pcorr&lt;0.01) (Table 1). Whilst relatively high proportions of so-called “DM-specific” rashes were seen in ASS skin, the frequency of heliotrope rash, Gottron’s papules, violaceous rash, periorbital rash, V-sign, shawl sign, and periungual erythema was significantly higher in DM skin (pcorr&lt;0.01 for all). Conversely, mechanic’s hands, Raynaud’s, arthritis, and interstitial lung disease were more frequent in ASS skin (pcorr&lt;0.01 for all). Malignancy was less frequent in ASS skin vs DM skin (pcorr&lt;0.01) and occurred temporally closer to myositis diagnosis in DM skin (median 0.95 months [IQR -6.54. to 19.45]) vs ASS skin (median 12.17 months [IQR -15.85 to 79.31]).

Conclusion

Patients with ASS have frequent skin involvement but also a distinct clinical phenotype compared to DM. These findings may inform the development of future classification criteria for ASS.

Disclosure

R.M. Hum: None. J.B. Lilleker: None. J.A. Lamb: None. W.E. Ollier: None. G. Wang: None. L.R. Wedderburn: None. L.P. Diederichsen: None. J. Schmidt: None. P. Oakley: None. O. Benveniste: None. M.G. Danieli: None. K. Danko: None. N.T.P. Thuy: None. M.V.D. Mercado: None. H. Andersson: None. B.D. Paepe: None. J.L.D. Bleecker: None. B. Maurer: None. L.J. McCann: None. N. Pipitone: None. N. McHugh: None. P. New: None. J. Vencovsky: None. I.E. Lundberg: None. H. Chinoy: None.

Trajectories of humoral and cellular immunity and responses to a third dose of mRNA vaccines against SARS-CoV-2 in patients with a history of anti-CD20 therapy

BACKGROUND

The majority of patients with B-cell-depleting therapies show compromised vaccination-induced immune responses. Herein, we report on the trajectories of anti-SARS-CoV-2 immune responses in patients of the RituxiVac study compared with healthy volunteers and investigate the immunogenicity of a third vaccination in previously humoral non-responding patients.

METHODS

We investigated the humoral and cell-mediated immune response after SARS-CoV-2 messanger RNA vaccination in patients with a history with anti-CD20 therapies. Coprimary outcomes were antispike and SARS-CoV-2-stimulated interferon-γ concentrations in vaccine responders 4.3 months (median; IQR: 3.6-4.8 months) after first evaluation, and humoral and cell-mediated immunity (CMI) after a third vaccine dose in previous humoral non-responders. Immunity decay rates were compared using analysis of covariance in linear regression.

RESULTS

5.6 months (IQR: 5.1-6.7) after the second vaccination, we detected antispike IgG in 88% (29/33) and CMI in 44% (14/32) of patients with a humoral response after two-dose vaccination compared with 92% (24/26) healthy volunteers with antispike IgG and 69% (11/16) with CMI 6.8 months after the second vaccination (IQR: 6.0-7.1). Decay rates of antibody concentrations were comparable between patients and controls (p=0.70). In two-dose non-responders, a third SARS-CoV-2 vaccine elicited humoral responses in 19% (6/32) and CMI in 32% (10/31) participants.

CONCLUSION

This study reveals comparable immunity decay rates between patients with anti-CD20 treatments and healthy volunteers, but inefficient humoral or CMI after a third SARS-CoV-2 vaccine in most two-dose humoral non-responders calling for individually tailored vaccination strategies in this population.Trial registration numberNCT04877496; ClinicalTrials.gov number.

Humoral and cellular immune responses on SARS-CoV-2 vaccines in patients with anti-CD20 therapies: a systematic review and meta-analysis of 1342 patients

BACKGROUND

Immune responses on SARS-CoV-2 vaccination in patients receiving anti-CD20 therapies are impaired but vary considerably. We conducted a systematic review and meta-analysis of the literature on SARS-CoV-2 vaccine induced humoral and cell-mediated immune response in patients previously treated with anti-CD20 antibodies.

METHODS

We searched PubMed, Embase, Medrxiv and SSRN using variations of search terms 'anti-CD20', 'vaccine' and 'COVID' and included original studies up to 21 August 2021. We excluded studies with missing data on humoral or cell-mediated immune response, unspecified methodology of response testing, unspecified timeframes between vaccination and blood sampling or low number of participants (≤3). We excluded individual patients with prior COVID-19 or incomplete vaccine courses. Primary endpoints were humoral and cell-mediated immune response rates. Subgroup analyses included time since anti-CD20 therapy, B cell depletion and indication for anti-CD20 therapy. We used random-effects models of proportions.

FINDINGS

Ninety studies were assessed. Inclusion criteria were met by 23 studies comprising 1342 patients. Overall rate of humoral response was 0.40 (95% CI 0.35 to 0.47). Overall rate of cell-mediated immune responses was 0.71 (95% CI 0.57 to 0.87). A time interval >6 months since last anti-CD20 therapy was associated with higher humoral response rates with 0.63 (95% CI 0.53 to 0.72) versus <6 months 0.2 (95% CI 0.03 to 0.43); p=0<01. Similarly, patients with circulating B cells more frequently showed humoral responses. Anti-CD20-treated kidney transplant recipients showed lower humoral response rates than patients with haematological malignancies or autoimmune disease.

INTERPRETATION

Patients on anti-CD20 therapies can develop humoral and cell-mediated immune responses after SARS-CoV-2 vaccination, but subgroups such as kidney transplant recipients or those with very recent therapy and depleted B cell are at high risk for non-seroconversion and should be individually assessed for personalised SARS-CoV-2 vaccination strategies. Potential limitations are small patient numbers and heterogeneity of studies included.

FUNDING

This study was funded by Bern University Hospital.

Case Report: Genetic Double Strike: VEXAS and TET2-Positive Myelodysplastic Syndrome in a Patient With Long-Standing Refractory Autoinflammatory Disease

Somatic genetic mutations involving the innate and inflammasome signaling are key drivers of the pathogenesis of myelodysplastic syndromes (MDS). Herein, we present a patient, who suffered from a long-standing refractory adult-onset autoinflammatory syndrome (AIS), previously interpreted as various distinct rheumatic disorders. Developing pancytopenia and particularly macrocytic anemia prompted the screening for a hematological malignancy, which led to the diagnosis of a TET-2-positive MDS. The impressive and continuously changing range of organ involvement, with remarkable refractoriness to anti-inflammatory treatment, exceeded the common autoinflammatory phenotype of MDS patients. This prompted us to suspect a recently discovered disease, characterized by somatic mutations of the UBA1 gene: the VEXAS (Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) syndrome, which was ultimately confirmed by genetic testing. Reevaluation of previous bone marrow biopsies showed the presence of characteristic vacuoles in myeloid- and erythroid progenitor cells. Our case illustrates that the triad of an unresponsive multisystemic autoinflammatory disease, hematological abnormalities and vacuoles in myeloid- and erythroid progenitors in the bone marrow biopsy should prompt screening for the VEXAS syndrome.

Humoral and cellular responses to mRNA vaccines against SARS-CoV-2 in patients with a history of CD20 B-cell-depleting therapy (RituxiVac): an investigator-initiated, single-centre, open-label study

BACKGROUND

B-cell-depleting therapies increase the risk of morbidity and mortality due to COVID-19. Evidence-based SARS-CoV-2 vaccination strategies for patients on B-cell-depleting therapies are scarce. We aimed to investigate humoral and cell-mediated immune responses to SARS-CoV-2 mRNA-based vaccines in patients receiving CD20-targeted B-cell-depleting agents for autoimmune disease, malignancy, or transplantation.

METHODS

The RituxiVac study was an investigator-initiated, single-centre, open-label study done at the Bern University Hospital (Bern, Switzerland). Patients with a treatment history of anti-CD20-depleting agents (rituximab or ocrelizumab) and with no previous history of SARS-CoV-2 infection were enrolled between April 26 and June 30, 2021, for analysis of humoral and cell-mediated immune responses (by interferon-γ [IFNγ] release assay) at least 4 weeks after completing vaccination against SARS-CoV-2. Healthy controls without a history of SARS-CoV-2 infection were also enrolled at least 4 weeks after completing vaccination against SARS-CoV-2. All study participants received two doses of either the Pfizer-BioNTech BNT162b2 vaccine or the Moderna mRNA-1273 vaccine. The primary outcome was the proportion of patients with a history of anti-CD20 treatment who showed a humoral immune response against the SARS-CoV-2 spike protein in comparison with immunocompetent controls. Prespecified secondary endpoints were the effect of anti-CD20 therapy (including time since last treatment and cumulative dose) on humoral or cell-mediated immune responses to SARS-CoV-2 vaccination, and biomarkers of immunocompetence. This study is registered with ClinicalTrials.gov, NCT04877496.

FINDINGS

The final study population comprised 96 patients and 29 immunocompetent controls. The median age of patients was 67 years (IQR 57-72) and of controls was 54 years (45-62), and 51 (53%) of 96 patients and 19 (66%) of 29 controls were female. The median time since last anti-CD20 treatment was 1·07 years (IQR 0·48-2·55) and the median cumulative dose of an anti-CD20 depleting agent was 2·80 g (1·50-5·00). Anti-spike IgG antibodies were detected in 47 (49%) of 96 patients 1·79 months (IQR 1·16-2·48) after the second vaccine dose compared to 29 (100%) of 29 controls 1·81 months (1·17-2·48) after the second vaccine dose (p<0·001). SARS-CoV-2-specific IFNγ release was detected in 13 (20%) of 66 patients and 21 (75%) of 28 of healthy controls (p<0·001). Only nine (14%) of 66 patients were double positive for anti-SARS-CoV-2 spike IgG and cell-mediated responses, compared with 21 (75%) of 28 healthy controls (p<0·001). Time since last anti-CD20 therapy (>7·6 months; positive predictive value 0·78), peripheral CD19+ cell count (>27 cells per μL; positive predictive value 0·70), and CD4+ lymphocyte count (>653 cells per μL; positive predictive value 0·71) were predictive of humoral vaccine response (area under the curve [AUC] 67% [95% CI 56-78] for time since last anti-CD20 therapy, 67% [55-80] for peripheral CD19+ count, and 66% [54-79] for CD4+ count).

INTERPRETATION

This study provides further evidence of blunted humoral and cell-mediated immune responses elicited by SARS-CoV-2 mRNA vaccines in patients with a history of CD20 B-cell-depleting treatment. Lymphocyte subpopulation counts were associated with vaccine response in this highly vulnerable population. On validation, these results could help guide both the administration of SARS-CoV-2 vaccines and B-cell-depleting agents in this population.

FUNDING

Bern University Hospital.

Computed tomography-based radiomics decodes prognostic and molecular differences in interstitial lung disease related to systemic sclerosis

Background

Radiomic features calculated from routine medical images show great potential for personalised medicine in cancer. Patients with systemic sclerosis (SSc), a rare, multiorgan autoimmune disorder, have a similarly poor prognosis due to interstitial lung disease (ILD). Here, our objectives were to explore computed tomography (CT)-based high-dimensional image analysis (“radiomics”) for disease characterisation, risk stratification and relaying information on lung pathophysiology in SSc-ILD.

Methods

We investigated two independent, prospectively followed SSc-ILD cohorts (Zurich, derivation cohort, n=90; Oslo, validation cohort, n=66). For every subject, we defined 1355 robust radiomic features from standard-of-care CT images. We performed unsupervised clustering to identify and characterise imaging-based patient clusters. A clinically applicable prognostic quantitative radiomic risk score (qRISSc) for progression-free survival (PFS) was derived from radiomic profiles using supervised analysis. The biological basis of qRISSc was assessed in a cross-species approach by correlation with lung proteomic, histological and gene expression data derived from mice with bleomycin-induced lung fibrosis.

Results

Radiomic profiling identified two clinically and prognostically distinct SSc-ILD patient clusters. To evaluate the clinical applicability, we derived and externally validated a binary, quantitative radiomic risk score (qRISSc) composed of 26 features that accurately predicted PFS and significantly improved upon clinical risk stratification parameters in multivariable Cox regression analyses in the pooled cohorts. A high qRISSc score, which identifies patients at risk for progression, was reverse translatable from human to experimental ILD and correlated with fibrotic pathway activation.

Conclusions

Radiomics-based risk stratification using routine CT images provides complementary phenotypic, clinical and prognostic information significantly impacting clinical decision making in SSc-ILD.

CT-based radiomics decodes phenotypic, prognostic and molecular differences in SSc-ILD, and predicts progression-free survival with a significant impact on future clinical decision making in SSc-ILDhttps://bit.ly/3zPaMOn

Staphylococcus aureus impairs dermal fibroblast functions with deleterious effects on wound healing

Chronic wounds are a major disease burden worldwide. The breach of the epithelial barrier facilitates transition of skin commensals to invasive facultative pathogens. Therefore, we investigated the potential effects of Staphylococcus aureus (SA) on dermal fibroblasts as key cells for tissue repair. In co-culture systems combining live or heat-killed SA with dermal fibroblasts derived from the BJ-5ta cell line, healthy individuals, and patients with systemic sclerosis, we assessed tissue repair including pro-inflammatory cytokines, matrix metalloproteases (MMPs), myofibroblast functions, and host defense responses. Only live SA induced the upregulation of IL-1β/-6/-8 and MMP1/3 as co-factors of tissue degradation. Additionally, the increased cell death reduced collagen production, proliferation, migration, and contractility, prerequisite mechanisms for wound closure. Intracellular SA triggered inflammatory and type I IFN responses via intracellular dsDNA sensor molecules and MyD88 and STING signaling pathways. In conclusion, live SA affected various key tissue repair functions of dermal fibroblasts from different sources to a similar extent. Thus, SA infection of dermal fibroblasts should be taken into account for future wound management strategies.

Diffuse myocardial fibrosis precedes impairment of myocardial strain in patients with systemic sclerosis

Funding Acknowledgements

Type of funding sources: None.

Background - Myocardial involvement is common in patients with systemic sclerosis (SSc) and causes myocardial fibrosis and subtle ventricular dysfunction. However, the temporal onset of myocardial involvement during the progression of the disease is yet unknown.

Purpose - To investigated the presence of subclinical functional impairment and diffuse myocardial fibrosis in patients with very early diagnosis of SSc (VEDOSS) and to compared the findings to patients with established SSc and healthy controls.

Methods - 110 SSc patients (86 with established SSc and 24 with VEDOSS) and 15 healthy controls were prospectively recruited. The study subjects underwent cardiovascular magnetic resonance on a clinical 1.5T system. Pre- and post-contrast T1 mapping was performed using a MOLLI (Modified Look-Locker Inversion Recovery) sequence. For extracellular volume (ECV) measurements, a single bolus protocol with image acquisition 15-20 min. post-contrast injection was used. For the assessment of subtle functional impairment, global longitudinal (GLS) and circumferential (GCS) myocardial strain were evaluated.

Results - Native T1 values and ECV were elevated in VEDOSS and in patients with established SSc compared to controls (p &lt; 0.001; Figure 1 A & B). GLS was similar in VEDOSS and controls but significantly reduced in patients with established SSc (p &lt; 0.001; Figure 1 C). GCS was similar over all groups (p = 0.88). Patients with clinical evidence of pulmonary or gastrointestinal involvement had higher ECV or T1 values, respectively. Patients with clinical signs of cardiac involvement had lower absolute GLS. SSc subtype, classification or disease duration were not associated with the extent of myocardial fibrosis or impaired strain.

Conclusion - Subclinical myocardial involvement first manifests as diffuse myocardial fibrosis identified by expansion of ECV and increased native T1 in VEDOSS patients while subtle functional impairment as measured by GLS only occurs in established SSc. No single clinical feature of SSc shows a strong association with subtle myocardial involvement.

The Hospital Anxiety and Depression Scale in patients with systemic sclerosis: a psychometric and factor analysis in a monocentric cohort

OBJECTIVES

To evaluate the feasibility, validity, reliability, and responsiveness of the Hospital Anxiety and Depression Scale (HADS) and to analyse its model structure in patients with systemic sclerosis (SSc).

METHODS

In this study, 316 SSc patients were included; of these, 159 participated in the responsiveness analysis. Psychometric properties were tested in analogy to the Outcome Measures in Rheumatology (OMERACT) filter and an exploratory and confirmatory factor analysis was performed to examine the structure of HADS.

RESULTS

The HADS showed adequate feasibility, validity, reliability, and responsiveness to clinically relevant worsening of the disease. For our population of SSc patients, the HADS model with two sub-scales, HADS-A and HADS-D, and a general scale HADS-S, measuring anxiety, depression, and distress, respectively, was most appropriate. The rates of anxiety, depression, mixed anxiety-depressive disorder (MADD) and distress identified by HADS were 32.2%, 25.9%, 18.5%, and 49.5%, respectively, in our cohort.

CONCLUSIONS

The psychometric properties of the HADS make it useful for screening in SSc, where anxiety, depression, MADD, and distress represent a significant burden to patients.

OP0150 MACHINE LEARNING APPROACHES FOR RISK MODELLING IN INTERSTITIAL LUNG DISEASE ASSOCIATED WITH SYSTEMIC SCLEROSIS USING HIGH DIMENSIONAL IMAGE ANALYSIS

Background:

The interstitial lung disease (ILD) associated with connective tissue diseases including systemic sclerosis (SSc) is heterogenous disease characterized by reduced survival of approximately 3 years (1). “Radiomics’’ is a field of research which describes the in-depth analysis of tissues by computational retrieval of high-dimensional quantitative features from medical images (2). Our previous study suggested capacity of radiomics features to differentiate between “high” and “low” risk groups for lung function decline in two independent cohorts (3).

Objectives:

  •bTo develop robust, machine learning (ML) workflow for “radiomics” data in SSc-ILD to select optimal methods for prediction.

  •oTo predict the time to individual lung function decline defined as defined by the time to a relative decline of ≥ 15% in Forced Vital Capacity (FVC)% as previously (3), using workflow.

Methods:

We investigated two cohorts of SSc-ILD: 90 patients (76.7% female, median age 57.5 years) from the University Hospital Zurich and 66 patients (75.8% female, median age 61.0 years) from Oslo University Hospital’s. Patients were retrospectively selected if (3): a) diagnosed with early/mild SSc according to the Very Early Diagnosis of Systemic Sclerosis (VEDOSS) criteria, b) presence of ILD on HRCT as determined by a senior radiologist. For every subject, we defined 1,355 robust radiomic features from HRCT images. The follow-up period was defined as the time interval between baseline visit and the last available follow-up visit.

We have developed a systematic computational workflow to build predictive ML models. To reduce the number of redundant radiomic features, we applied correlation thresholds. We applied distinct methods including 1) Lasso Penalized Regression for feature selection, and 2) Random Forest (RF) for modeling using the R package ‘caret’. To select the optimal ML model, we randomly divided derivation cohort into Training (70%) and Holdout (30%) sets and applied fivefold cross-validation (5kCV) for feature and classifier selection on Training set only.

Results:

We have investigated various methods to select the optimal set of predictive radiomic features. Since the ML model performance is affected by both, feature, and classifier selection, we assessed these factors first.

Results from feature filtering and selection, suggested that the combination of correlation threshold of 0.9 with Lasso regression proved best. As we perform feature selection in 5k CV workflow, features present in at least 2 sets entered model optimization step.

During model selection, we selected RF classifier. We detected positive correlation between actual and predicted values with Spearman’s rho = 0.313, p = 0.167 and Spearman’s rho = 0.341, p = 0.015 in Oslo and Holdout sets respectively, as shown on Figure 1. The percentage of variance remained modest for both Holdout (Rsq = 0.104) and Oslo (Rsq = 0.126) datasets.

Figure 1.

Performance of the best, RF classifier shown as scatterplot between actual and predicted values of individual time to lung decline.

Conclusion:

In summary, we: (1) developed ML workflow that allowed to select o optimal methodology for modeling (i.e., feature and classifier selection), and (2) provide models that predicted time to individual lung function decline, characterized by significant correlation between predicted and actual values.

References:

[1]Hansell DM, Goldin JG, King TE, Jr., Lynch DA, Richeldi L, Wells AU. CT staging and monitoring of fibrotic interstitial lung diseases in clinical practice and treatment trials: a position paper from the Fleischner Society. Lancet Respir Med. 2015;3(6):483-96.

[2]Lambin, P. et al. Radiomics: extracting more information from medical images using advanced feature analysis. Eur. J. Cancer 48, 441–446 (2012).

[3]Schniering J. et al. Resolving phenotypic and prognostic differences in interstitial lung disease related to systemic sclerosis by computed tomography-based radiomics. https://www.medrxiv.org/content/10.1101/2020.06.09.20124800v1

Disclosure of Interests:

None declared

AB0411 CHALLENGES IN THE MANAGEMENT OF MIXED CONNECTIVE TISSUE DISEASE: A RETROSPECTIVE ANALYSIS OF THE MCTD COHORT IN A TERTIARY REFERRAL CENTRE

Background:

As a rare, complex, and heterogeneous disease, mixed connective tissue disease (MCTD) represents a challenge for clinical practice.

Objectives:

We aimed to unravel potential pitfalls including correct referral diagnosis, fulfilment of diagnostic criteria, distinction from other CTDs, disease course and activity, and treatment modalities.

Methods:

We analysed the prospectively collected MCTD cohort at our tertiary referral centre. The patients’ medical histories were investigated for fulfilment of Sharp’s (1), Kasukawa’s (2), and Alarcón-Segovia’s (3) diagnostic MCTD criteria. We defined overlap syndromes as simultaneous fulfilment of clinical as well as immunological criteria of two defined rheumatic diseases. Disease conversion was defined as emergence of new symptoms and autoantibodies consistent with another rheumatic disease. Remission was defined by simultaneous systemic lupus erythematosus disease activity index 2000 (SLEDAI-2 K) of 0 and European League Against Rheumatism scleroderma trial and research (EUSTAR) activity index <2.5. Disease phenotype and disease activity were monitored over time and all patients were evaluated for fulfilment of classification criteria of various connective tissue diseases.

Results:

Out of 85 patients initially referred as MCTD, only one third fulfilled the diagnostic MCTD criteria. Most of the remaining patients had undifferentiated CTD (29%) or overlap syndromes (20%). In our final cohort of 33 MCTD patients, 6 (48%) also met the classification criteria of systemic sclerosis, 13 (39%) those of systemic lupus erythematosus (SLE), 6 (18%) those of rheumatoid arthritis, and 3 (9%) those of primary myositis. Over the median observation period of 4.6 (1.6, 9.9) years, only two patients (6%) underwent disease conversion from MCTD to SLE and no patient converted towards other diseases. The number of patients in remission increased from 6 (18%) to 15 (45%) due to introduction of immune modulatory treatment. Combination therapy was favoured in most cases (17 patients, 52%), whereas monotherapy was less frequent (12 patients, 36%), and only 4 (12%) patients remained without immune modulators until the end of the follow-up period. Hydroxychloroquine, prednisone, and methotrexate were the most frequently used medications in our cohort.

Conclusion:

Our study showed a high risk for misdiagnosis for patients with MCTD. Phenotype conversion was a very rare event. As a multi-organ disease, MCTD required prolonged (combined) immunosuppressive therapy to achieve remission. The establishment of an international registry with longitudinal data from observational multi-centre cohorts might represent a first step to address the many unmet needs of MCTD.

References:

[1]Sharp GC. Diagnostic criteria for classification of MCTD. In: Kasukawa R, Sharp GC, editors. Mixed connective tissue disease and anti-nuclear antibodies: proceedings of the International Symposium on Mixed Connective Tissue Disease and Anti-nuclear Antibodies, Tokyo, 29-30 August 1986. no. 719. Amsterdam: Elsevier Science Publishers B.V. (Biomedical Division); 1987. p. 23-30.

[2]Kasukawa R, Tojo T, Miyawaki S, Yoshida H, Tanimoto K, Nobunaga M, et al. Preliminary diagnostic criteria for classification of mixed connective tissue disease. In: Kasukawa R, Sharp GC, editors. Mixed connective tissue disease and anti-nuclear antibodies: proceedings of the International Symposium on Mixed Connective Tissue Disease and Anti-nuclear Antibodies, Tokyo, 29-30 August 1986. no. 719. Amsterdam: Elsevier Science Publishers B.V. (Biomedical Division); 1987. p. 41-7.

[3]Alarcón-Segovia D, Villarreal M. Classification and diagnostic criteria for mixed connective tissue disease. In: Kasukawa R, Sharp GC, editors. Mixed connective tissue disease and anti-nuclear antibodies: proceedings of the International Symposium on Mixed Connective Tissue Disease and Anti-nuclear Antibodies, Tokyo, 29-30 August 1986. no. 719. Amsterdam: Elsevier Science Publishers B.V. (Biomedical Division); 1987. p. 33-40.

Disclosure of Interests:

Adrian Wanzenried: None declared, Alexandru Garaiman: None declared, Suzana Jordan: None declared, Oliver Distler Consultant of: O.D. had consultancy relationship and/or has received research funding from Abbvie, Actelion, Acceleron Pharma, Amgen, AnaMar, Baecon Discovery, Blade Therapeutics, Bayer, Boehringer Ingelheim, Catenion, Competitive Drug Development International Ltd, CSL Behring, ChemomAb, Curzion Pharmaceuticals, Ergonex, Ga-lapagos NV, Glenmark Pharmaceuticals, GSK, Inventiva, Italfarmaco, iQone, iQvia, Lilly, medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Novartis, Pfizer, Roche, Sanofi, Target Bio Science and UCB in the area of potential treatments of scleroderma and its complications., Britta Maurer Consultant of: Boehringer-Ingelheim, Grant/research support from: AbbVie, Protagen, and Novartis Biomedical Research as well as congress support from Pfizer, Roche, Actelion, mepha, and MSD.

POS0795 ULTRASOUND-GUIDED CORE NEEDLE BIOPSY: AN EFFECTIVE AND SAFE TOOL TO DIAGNOSE SJÖGREN`S SYNDROME AND LYMPHOMA OF THE MAJOR SALIVARY GLANDS

Background:

Histopathology is a cornerstone of diagnostics in Sjögren`s syndrome (SjS). The current widely accepted standard, minor salivary gland (lip) biopsy, is a surgical procedure with several disadvantages including permanent sensory loss of the lips as a well-known complication (reviewed in 1). Moreover, lymphoma of salivary glands cannot be excluded. Ultrasound-guided core needle biopsy (CNB) is an excellent diagnostic tool with good safety (2) and encouraging results as compared to open biopsy (3).

Objectives:

To retrospectively analyze safety and diagnostic outcome of ultrasound-guided CNB in patients with known or suspected SjS.

Methods:

A retrospective analysis of a case series of four patients with known or suspected SjS. All patients were treated at the outpatient clinic of the Department of Rheumatology & Immunology, and the Department of Otorhinolaryngology. All patients underwent ultrasound-guided CNB: We clean and disinfect the ultrasound transducer and the skin of the patient before and after the procedure. We use a sterile probe cover and gloves. Only sterile ultrasound gel or ultrasound compatible disinfectant should be used. Core-needle biopsy was performed using a 20 g needle (Bard). A Logiq S8 GE ultrasound device with a 6-15 MHz matrix linear transducer was used. We performed a local anesthesia at the entry point and a 2mm skin incision. The sampling length was set on 20mm. The CNB was performed at the most suspicious focal sonographic lesion. 2-3 needle passes were carried out through the same skin access.

Results:

Representative histopathological samples were obtained from all patients. In patient 1 (62y) with known SjS and parotid swelling, mucosa-associated lymphoid tissue (MALT) lymphoma was diagnosed (previous lip biopsy with no proof of malignancy). Also in patient 2 (35y) with known SjS and a 20-years history of parotid swelling, MALT lymphoma was diagnosed. In this patient a lip biopsy was performed in the previous year supporting the diagnosis of SjS, but without proof of malignancy. In patient 3 (64y) with SSc, anti-Ro/SSA positivity and dry eyes and mouth, the biopsy established the diagnosis of SjS. In patient 4 (59y) with SSc, negative anti-Ro/SSA antibodies and dry eyes/mouths, SjS could be excluded. In the corresponding ultrasound, all patients showed hypoechogenic lesions and inhomogeneous parenchyma of major salivary glands reflecting OMERACT grade II-III SjS ultrasound score (4). No safety signals were observed. Patients with prior lip biopsies perceived ultrasound-guided CNB as preferable.

Conclusion:

This pilot study suggests that ultrasound-guided CNB in SjS is a safe procedure with an excellent diagnostic yield allowing the diagnosis of lymphoma of the salivary glands, which is superior to lip biopsy. Given these encouraging results, we will now increase patient numbers for further validation.

References:

[1]Pijpe, J., et al., Parotid gland biopsy compared with labial biopsy in the diagnosis of patients with primary Sjogren’s syndrome. Rheumatology (Oxford), 2007. 46(2): p. 335-41.

[2]Kim, H.J. et al., Ultrasound-guided core needle biopsy in salivary glands: A meta-analysis. Laryngoscope, 2018. 128(1): p. 118-125.

[3]Zabotti, A. et al., Ultrasound-guided core needle biopsy compared with open biopsy: a new diagnostic approach to salivary gland enlargement in Sjögren’s syndrome? Rheumatology (Oxford). 2020.17:keaa441. Epub ahead of print.

[4]Jousse-Joulin, S., et al., Video clip assessment of a salivary gland ultrasound scoring system in Sjogren’s syndrome using consensual definitions: an OMERACT ultrasound working group reliability exercise. Ann Rheum Dis, 2019. 78(7): p. 967-973.

Disclosure of Interests:

Urs Borner: None declared, Lluis Nisa Hernandez: None declared, Adela-Cristina Sarbu: None declared, Lisa Christ Shareholder of: Roche, Grant/research support from: Gilead, Roche, Pfizer, Yara Banz: None declared, Britta Maurer Speakers bureau: Boehringer-Ingelheim, Grant/research support from: Abbvie, Protagen, Novartis Biomedical Research and congress support from Pfizer, Roche, Actelion, mepha, and MSD. BM has a patent for mir-29 for the treatment of systemic sclerosis issued (US8247389, EP233143)., Marco D. Caversaccio Grant/research support from: Medel, Cochlear, Oticon, Storz, Florian Kollert Shareholder of: Roche, Consultant of: Actelion, BMS, Boehringer-Ingelheim, Pfizer, Grant/research support from: Gilead, Pfizer, Employee of: In the past at Novartis, currently at Roche

POS0866 TWO-DIMENSIONAL HRCT-BASED RADIOMIC FEATURES IN SSC-ILD DISTINGUISH DRUG RESPONDERS FROM NON-RESPONDERS

Background:

Management of patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD) is complicated by high inter-patient variability. To date, no validated predictors of treatment response are available for routine use. High resolution computed tomography (HRCT)-based radiomics, i.e. the high-dimensional, quantitative analysis of imaging metadata, have previously been shown to be successful in discriminating (SSc-)ILD phenotypes in preclinical and clinical studies1. Since HRCT is an integral part of the routine work-up in SSc, HRCT-based radiomic features may hold potential as non-invasive biomarkers.

Objectives:

To predict treatment response using two-dimensional (2D) HRCT-based radiomics in SSc-ILD patients from a prospectively followed cohort.

Methods:

Inclusion criteria were diagnosis of SSc-ILD in HRCT, availability of a suitable chest HRCT scan within 12 months prior to initiation of a new treatment, and availability of clinical baseline and follow-up information. Treatment response was defined as the absence of all of the following over a follow-up period of 12-24 months: relative decrease in forced vital capacity (FVC) ≥5%, increase of ILD in HRCT as assessed by a radiologist, change in treatment regimen due to insufficient response, ILD-related death or lung transplantation. Of each pre-treatment HRCT, 6 slices (15±5 mm apart, starting from the basal lung margin) were manually segmented and 1513 2D radiomic features were extracted using the in-house software Z-Rad (Python 2.7). Features were Z-score transformed and pre-filtered for inter- and intra-reader robustness (intraclass correlation coefficient >0.85) and inter-feature correlation (Spearman’s rho <0.9). A categorical linear regression model was created using 3-fold cross-validated elastic nets for feature selection. Features were then summarized and divided by their number. For generation of a score cut-off, Youden’s score was used. For two-group analyses of continuous variables, Wilcoxon’s test was performed, whereas categorical data was assessed using Fisher’s exact test.

Results:

A total of 64 pre-treatment HRCTs from 54 patients were analyzed. In 9 patients, >1 asynchronous treatments were assessed, while 45 patients had only 1 eligible treatment approach. The response rate within the assessed follow-up period was 45.3% (n=29). For score generation, 13 radiomic features were selected and an optimal cut-off value of -0.1589 was determined. Univariate linear regression showed significant association between our categorical radiomics-based score and treatment response (p=0.007, area under the curve = 0.65 (0.51-0.79), sensitivity=0.90, specificity=0.43), whereby a high score was predictive for treatment response.

No differences between patients with high (n=46) or low (n=18) scores were detected for baseline age (mean±SD=55.5±12.0 and 55.5±13.6 years, p=0.84), duration of SSc (mean±SD=6.2±8.4 and 4.7±4.4 years, p=0.79), time since ILD diagnosis (2.7±2.9 and 2.4±3.1 years, p=0.59), FVC (77.6±20.6 and 80.1±17.9, p=0.41) or DLco (54.4±21.0 and 57.6±18.9, p=0.40). Distribution of anti-Scl-70 positivity (45.7% vs. 55.6%, p=0.58) and diffuse cutaneous disease (47.7% vs. 61.1%, p=0.41) was not significantly different between patients with high and low scores, respectively, although a trend towards higher percentages in the high score group was observed.

Conclusion:

Our results indicate that, following validation in external cohorts, radiomics may be a promising tool for future pre-treatment patient stratification. Moreover, our radiomics-based score seems not to be associated with commonly studied clinical predictors such as anti-Scl-70 positivity or lung function, underlining a possible additive value to ‘traditional’ clinical parameters.

References:

[1]Schniering, J., et al. Resolving phenotypic and prognostic differences in interstitial lung disease related to systemic sclerosis by computed tomography-based radiomics. medRxiv [Preprint] doi:10.1101/2020.06.09.20124800 (2020).

Disclosure of Interests:

Chantal Meier: None declared, Malgorzata Maciukiewicz: None declared, Matthias Brunner: None declared, Janine Schniering: None declared, Hubert Gabrys: None declared, Anja Kühnis: None declared, Oliver Distler Speakers bureau: Speaker fee on Scleroderma and related complications: Bayer, Boehringer Ingelheim, Medscape, Novartis, Roche. Speaker fee on rheumatology topic other than Scleroderma: MSD, iQone, Novartis, Pfizer, Roche, Consultant of: Consultancy fee for Scleroderma and its complications: Abbvie, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Bayer, Baecon Discovery, Boehringer, CSL Behring, ChemomAb, Corbus Pharmaceuticals, Horizon Pharmaceuticals, Galapagos NV, GSK, Glenmark Pharmaceuticals, Inventiva, Italfarmaco, iQvia, Kymera, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Roche, Roivant Sciences, Sanofi, UCB. Consultancy fee for rheumatology topic other than Scleroderma: Abbvie, Amgen, Lilly, Pfizer, Grant/research support from: Research Grants to investigate the pathophysiology and potential treatment of Scleroderma and its complications: Kymera Therapeutics, Mitsubishi Tanabe, Thomas Frauenfelder: None declared, Stephanie Tanadini-Lang: None declared, Britta Maurer Speakers bureau: Speaker fees from Boehringer-Ingelheim, Grant/research support from: Grant/research support from AbbVie, Protagen, Novartis Biomedical Research, congress support from Pfizer, Roche, Actelion, mepha, and MSD

Performance of the UCLA Scleroderma Clinical Trials Consortium Gastrointestinal Tract 2.0 instrument as a clinical decision aid in the routine clinical care of patients with systemic sclerosis

BACKGROUND AND OBJECTIVES

The University of California Los Angeles Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument 2.0 (UCLA GIT 2.0) is validated to capture gastrointestinal (GI) tract morbidity in patients with systemic sclerosis (SSc). The aims of this study were to determine in a large SSc cohort if the UCLA GIT 2.0 is able to discriminate patients for whom a rheumatologist with experience in SSc would recommend an esophago-gastro-duodenoscopy (EGD), and if it could identify patients with endoscopically proven esophagitis or with any pathologic finding on EGD.

METHODS

We selected patients fulfilling the ACR/EULAR 2013 criteria for SSc from our EUSTAR center having completed at least once the UCLA GIT 2.0 questionnaire, and we collected data on gastrointestinal symptoms and EGD from their medical charts. We analyzed by general linear mixed effect models several parameters, including UCLA GIT 2.0, considered as potentially associated with the indication of EGD, as well as with endoscopic esophagitis and any pathologic finding on EGD.

RESULTS

We identified 346 patients (82.7% female, median age 63 years, median disease duration 10 years, 23% diffuse cutaneous SSc) satisfying the inclusion criteria, who completed UCLA GIT 2.0 questionnaires at 940 visits. EGD was recommended at 169 visits. In multivariable analysis, UCLA GIT 2.0 and some of its subscales (reflux, distention/bloating, social functioning) were associated with the indication of EGD. In 177 EGD performed in 145 patients, neither the total ULCA GIT 2.0 score nor any of its subscales were associated with endoscopic esophagitis, nor with any pathologic EGD findings.

CONCLUSIONS

In a real-life setting, the UCLA GIT 2.0 and its reflux subscale were able to discriminate patients with SSc who had an indication for EGD, but did not correlate with findings in EGD. We conclude that, while using the UCLA GIT 2.0 in the routine care of patients with SSc may help the rheumatologist to better understand the burden of GI symptoms in the individual patient, it should not be used as a stand-alone instrument to identify an indication of EGD.

Integrative analysis of cell state changes in lung fibrosis with peripheral protein biomarkers

The correspondence of cell state changes in diseased organs to peripheral protein signatures is currently unknown. Here, we generated and integrated single-cell transcriptomic and proteomic data from multiple large pulmonary fibrosis patient cohorts. Integration of 233,638 single-cell transcriptomes (n = 61) across three independent cohorts enabled us to derive shifts in cell type proportions and a robust core set of genes altered in lung fibrosis for 45 cell types. Mass spectrometry analysis of lung lavage fluid (n = 124) and plasma (n = 141) proteomes identified distinct protein signatures correlated with diagnosis, lung function, and injury status. A novel SSTR2+ pericyte state correlated with disease severity and was reflected in lavage fluid by increased levels of the complement regulatory factor CFHR1. We further discovered CRTAC1 as a biomarker of alveolar type-2 epithelial cell health status in lavage fluid and plasma. Using cross-modal analysis and machine learning, we identified the cellular source of biomarkers and demonstrated that information transfer between modalities correctly predicts disease status, suggesting feasibility of clinical cell state monitoring through longitudinal sampling of body fluid proteomes.

Circulating collagen neo-epitopes and their role in the prediction of fibrosis in patients with systemic sclerosis: a multicentre cohort study

BACKGROUND

Extracellular matrix remodelling is a hallmark of systemic sclerosis. We evaluated extracellular matrix neo-epitopes as potential serum biomarkers for progression of fibrosis in systemic sclerosis.

METHODS

We included patients meeting the 2013 American College of Rheumatology and European League Against Rheumatism criteria and healthy controls from a derivation and validation cohort. The primary outcome was progression of fibrosis at follow-up, defined as decline in percentage of predicted forced vital capacity of 10% or more in patients with interstitial lung disease or increase in modified Rodnan skin score of 25% or more and more than 5 points at a 1-year follow-up visit. Longitudinal assessment and biobanking followed European Scleroderma Trials and Research standards. Extracellular matrix-degradation (BGM, C3M, C4M, and C6M) and extracellular matrix-formation neo-epitopes (PRO-C1, PRO-C3, PRO-C4, PRO-C5, and PRO-C6) were measured in serum using validated ELISAs.

FINDINGS

Between Aug 18, 2011, and Jan 19, 2015, 149 patients with systemic sclerosis (27 [18%] progressors and 122 [82%] non-progressors) and 29 healthy controls were included in the derivation cohort. Concentrations of type III and IV collagen neo-epitopes were higher in patients with systemic sclerosis compared with healthy controls and were significantly associated with systemic sclerosis in univariable logistic regression. Concentrations of degradation neo-epitopes of type III and IV collagens and their turnover ratios distinguished between progressors and non-progressors (C3M area under the curve 0·77 [95% CI 0·67-0·86], p<0·0001; PRO-C3:C3M 0·70 [0·59-0·80], p=0·0013; C4M 0·73 [0·63-0·82], p<0·0001; PRO-C4:C4M 0·75 [0·64-0·86], p<0·0001). 384 patients with systemic sclerosis (73 [19%] progressors) and 60 healthy controls were included in the multicentre validation cohort between April 17, 2003, and Jan 24, 2017. Analysis of the validation cohort confirmed that neo-epitopes of type III and IV collagens are changed in progressors. In a pooled analysis of both cohorts, the serum concentrations of formation neo-epitopes PRO-C3 and PRO-C4 and the turnover ratio of type IV collagen (PRO-C4:C4M) were higher in skin progressors. The turnover ratio of type IV collagen and PRO-C3 significantly predicted skin progression in a multivariable model adjusted for modified Rodnan skin score, sex, and age.

INTERPRETATION

These data suggest that neo-epitopes of type III and IV collagens are promising biomarkers for the assessment and prediction of extracellular matrix remodelling in systemic sclerosis. They could be used in clinical practice to risk stratify patients at risk of progression of fibrosis.

FUNDING

None.

Long noncoding RNA H19X is a key mediator of TGF-β-driven fibrosis

TGF-β is a master regulator of fibrosis, driving the differentiation of fibroblasts into apoptosis-resistant myofibroblasts and sustaining the production of extracellular matrix (ECM) components. Here, we identified the nuclear long noncoding RNA (lncRNA) H19X as a master regulator of TGF-β-driven tissue fibrosis. H19X was consistently upregulated in a wide variety of human fibrotic tissues and diseases and was strongly induced by TGF-β, particularly in fibroblasts and fibroblast-related cells. Functional experiments following H19X silencing revealed that H19X was an obligatory factor for TGF-β-induced ECM synthesis as well as differentiation and survival of ECM-producing myofibroblasts. We showed that H19X regulates DDIT4L gene expression, specifically interacting with a region upstream of the DDIT4L gene and changing the chromatin accessibility of a DDIT4L enhancer. These events resulted in transcriptional repression of DDIT4L and, in turn, in increased collagen expression and fibrosis. Our results shed light on key effectors of TGF-β-induced ECM remodeling and fibrosis.

Impact of CT convolution kernel on robustness of radiomic features for different lung diseases and tissue types

OBJECTIVES

In this study, we aimed to assess the impact of different CT reconstruction kernels on the stability of radiomic features and the transferability between different diseases and tissue types. Three lung diseases were evaluated, i.e. non-small cell lung cancer (NSCLC), malignant pleural mesothelioma (MPM) and interstitial lung disease related to systemic sclerosis (SSc-ILD) as well as four different tissue types, i.e. primary tumor, largest involved lymph node ipsilateral and contralateral lung.

METHODS

Pre-treatment non-contrast enhanced CT scans from 23 NSCLC, 10 MPM and 12 SSc-ILD patients were collected retrospectively. For each patient, CT scans were reconstructed using smooth and sharp kernel in filtered back projection. The regions of interest (ROIs) were contoured on the smooth kernel-based CT and transferred to the sharp kernel-based CT. The voxels were resized to the largest voxel dimension of each cohort. In total, 1386 features were analyzed. Feature stability was assessed using the intraclass correlation coefficient. Features above the stability threshold >0.9 were considered stable.

RESULTS

We observed a strong impact of the reconstruction method on stability of the features (at maximum 26% of the 1386 features were stable). Intensity features were the most stable followed by texture and wavelet features. The wavelet features showed a positive correlation between percentage of stable features and size of the ROI (R2 = 0.79, p = 0.005). Lymph node radiomics showed poorest stability (<10%) and lung radiomics the largest stability (26%). Robustness analysis done on the contralateral lung could to a large extent be transferred to the ipsilateral lung, and the overlap of stable lung features between different lung diseases was more than 50%. However, results of robustness studies cannot be transferred between tissue types, which was investigated in NSCLC and MPM patients; the overlap of stable features for lymph node and lung, as well as for primary tumor and lymph node was very small in both disease types.

CONCLUSION

The robustness of radiomic features is strongly affected by different reconstruction kernels. The effect is largely influenced by the tissue type and less by the disease type.

ADVANCES IN KNOWLEDGE

The study presents to our knowledge the most complete analysis on the impact of convolution kernel on the robustness of CT-based radiomics for four relevant tissue types in three different lung diseases. .

Pain chronification and the important role of non-disease-specific symptoms in patients with systemic sclerosis

Background

Pain is a frequent, yet inadequately explored challenge in patients with systemic sclerosis (SSc). This study aimed to conduct an extensive pain assessment, examining pain chronification and its association with disease manifestations.

Methods

Consecutive SSc patients attending their annual assessment were included. SSc-specific features were addressed as defined by the European Scleroderma Trials and Research (EUSTAR) guidelines. Pain analysis included intensity, localization, treatment, chronification grade according to the Mainz Pain Staging System (MPSS), general well-being using the Marburg questionnaire on habitual health findings (MFHW) and symptoms of anxiety and depression using the Hospital Anxiety and Depression Scale (HADS).

Results

One hundred forty-seven SSc patients completed a pain questionnaire, and 118/147 patients reporting pain were included in the analysis. Median pain intensity was 4/10 on a numeric rating scale (NRS). The most frequent major pain localizations were hand and lower back. Low back pain as the main pain manifestation was significantly more frequent in patients with very early SSc (p = 0.01); those patients also showed worse HADS and MFHW scores. Regarding pain chronification, 34.8% were in stage I according to the MPSS, 45.2% in stage II and 20.0% in stage III. There was no significant correlation between chronification grade and disease severity, but advanced chronification was significantly more frequent in patients with low back pain (p = 0.024). It was also significantly associated with pathological HADS scores (p < 0.0001) and linked with decreased well-being and higher use of analgesics.

Conclusions

Our study implies that also non-disease-specific symptoms such as low back pain need to be considered in SSc patients, especially in early disease. Since low back pain seems to be associated with higher grades of pain chronification and psychological problems, our study underlines the importance of preventing pain chronification in order to enhance the quality of life.

[The Long-COVID Syndrome - a New Clinical Picture after COVID-19 Infection]

The Long-COVID Syndrome - a New Clinical Picture after COVID-19 Infection Abstract. Long-term consequences are increasingly reported in the current literature after COVID-19 infections. Some patients suffer from persistent pulmonary and extrapulmonary symptoms even months after the acute infection. Pulmonary impairment, but also dysregulation and effects on immune system, cardiovascular system, neurological system, skin and kidney are described or anticipated. This mini review gives a short update to the practitioner about the current knowledge about Long COVID.

Serum metabolites as biomarkers in systemic sclerosis-associated interstitial lung disease

Systemic sclerosis (SSc) is a severe multi-organ disease with interstitial lung disease (ILD) being the major cause of death. While targeted therapies are emerging, biomarkers for sub-stratifying patients based on individual profiles are lacking. Herein, we investigated how levels of serum metabolites correlated with different stages of SSc and SSc-ILD. Serum samples of patients with SSc without ILD, stable and progressive SSc-ILD as well as of healthy controls (HC) were analysed using liquid targeted tandem mass spectrometry. The best discriminating profile consisted of 4 amino acids (AA) and 3 purine metabolites. L-tyrosine, L-tryptophan, and 1-methyl-adenosine distinguished HC from SSc patients. L-leucine, L-isoleucine, xanthosine, and adenosine monophosphate differentiated between progressing and stable SSc-ILD. In SSc-ILD, both, L-leucine and xanthosine negatively correlated with changes in FVC% predicted. Additionally, xanthosine was negatively correlated with changes in DLco% predicted and positively with the prognostic GAP index. Validation of L-leucine and L-isoleucine by an enzymatic assay confirmed both the sub-stratification of SSc-ILD patients and correlation with lung function and prognosis score. Serum metabolites may have potential as biomarkers for discriminating SSc patients based on the presence and severity of ILD. Confirmation in larger cohorts will be needed to appreciate their value for routine clinical care.

Can Nuclear Imaging of Activated Macrophages with Folic Acid-Based Radiotracers Serve as a Prognostic Means to Identify COVID-19 Patients at Risk?

Herein, we discuss the potential role of folic acid-based radiopharmaceuticals for macrophage imaging to support clinical decision-making in patients with COVID-19. Activated macrophages play an important role during coronavirus infections. Exuberant host responses, i.e., a cytokine storm with increase of macrophage-related cytokines, such as TNFα, IL-1β, and IL-6 can lead to life-threatening complications, such as acute respiratory distress syndrome (ARDS), which develops in approximately 20% of the patients. Diverse immune modulating therapies are currently being tested in clinical trials. In a preclinical proof-of-concept study in experimental interstitial lung disease, we showed the potential of ¹⁸F-AzaFol, an ¹⁸F-labeled folic acid-based radiotracer, as a specific novel imaging tool for the visualization and monitoring of macrophage-driven lung diseases. ¹⁸F-AzaFol binds to the folate receptor-beta (FRβ) that is expressed on activated macrophages involved in inflammatory conditions. In a recent multicenter cancer trial, ¹⁸F-AzaFol was successfully and safely applied (NCT03242993). It is supposed that the visualization of activated macrophage-related disease processes by folate radiotracer-based nuclear imaging can support clinical decision-making by identifying COVID-19 patients at risk of a severe disease progression with a potentially lethal outcome.

FRI0240 HOSPITAL ANXIETY AND DEPRESSION SCALE AND SENSE OF COHERENCE 13-ITEM SCALE IN A SWISS COHORT OF SYSTEMIC SCLEROSIS PATIENTS: VALIDITY, RELIABILITY AND SENSITIVITY TO CHANGE

Background:

Depression, anxiety and distress affect the quality of life of patients with systemic sclerosis (SSc) [1]. The Hospital Anxiety and Depression Scale (HADS) and Sense of Coherence 13-item scale (SOC-13, measuring comprehensibility, manageability and meaningfulness) are screening tools used in patients with different medical conditions. However, their validity, reliability and sensitivity to change in SSc patients has not been evaluated yet.

Objectives:

To examine the psychometric properties of HADS and its subscales HADS-A and HADS-D (measuring anxiety and depression symptoms, respectively), and unidimensional SOC-13 in a large cohort of Swiss SSc patients.

Methods:

Consecutive patients fulfilling the ACR/EULAR 2013 classification criteria for SSc who completed the HADS, SOC-13, Short Form-36 Health Survey (SF-36) and Scleroderma Health Assessment Questionnaire (SHAQ) were included in a cross-sectional and longitudinal analysis. Cronbach’s α, split-half reliability and construct validity were measured. Sensitivity to change (Cohen’s d coefficient) was assessed in patients who worsened within 12±3 months, defined as occurrence of any of the following events: decline in forced vital capacity (FVC)≥10%, new diagnosis of interstitial lung disease (ILD) on high-resolution computed tomography (HRCT), progression of known ILD to >20% lung involvement on HRCT (ILD20), new-onset pulmonary hypertension (PH), increase in European Scleroderma Study Group activity index (EScSG-AI) >3 points, new active digital ulcers, increase in modified Rodnan skin score (mRSS) > 7 points.

Results:

Of 345 patients (aged 59.34±14.17, 82.9% female, 18.8% with diffuse cutaneous SSc, 47.6% anti-centromere Ab-positive, 23.5% anti-Scl-70 Ab-positive, 13% anti-U1RNP Ab-positive and 11.3% anti-RNA polymerase III Ab-positive) 85 participated with a second visit to the sensitivity to change analysis.

Internal consistency was excellent for the HADS (Cronbach’s α=0.91; split-half reliability r=0.92), and very good for HADS-A, HADS-D and SOC-13 (Cronbach’s α=0.85-0.89; split-half reliability r=0.86-0.89).

Regarding construct validity, all four scales showed a strong to very strong correlation to each other, as well as with the mental components of SF-36 (Spearman’s r=0.63-0.85). There was a moderate to strong correlation with the SHAQ (Spearman’s r=0.45-0.64).

Regarding sensitivity to change: HADS-A showed a large to very large effect size (ES) for progression of ILD as assessed on HRCT and increase in EScSG-AI (Cohen’s d=1-1.63), and a very small to small ES for changes in FVC, DU and mRSS (Cohen’s d=0.02-0.45). HADS-D showed a large ES for changes in the ILD20, mRSS and EScSG-AI (Cohen’s d=0.82-1), and moderate ES for changes of FVC, ILD, PH, DU (Cohen’s d=0.1-0.49). SOC-13 showed generally a very small to small EF, except for change in mRSS (Cohen’s d=0.56).

Conclusion:

The HADS(A/D) and SOC-13 are valid and easy-to-use tools to detect depression, anxiety and distress in SSc. However, their sensitivity to change might be limited by the respective type of organ involvement and its impact on the patients’ psychological wellbeing.

References:

[1]Legendre C, Allanore Y, Ferrand I, Kahan A. Evaluation of depression and anxiety in patients with systemic sclerosis. Joint Bone Spine. 2005;72(5):408–411.

Disclosure of Interests:

Alexandru Garaiman: None declared, Carina Mihai: None declared, Rucsandra Dobrota: None declared, Suzana Jordan: None declared, Britta Maurer Grant/research support from: AbbVie, Protagen, Novartis, congress support from Pfizer, Roche, Actelion, and MSD, Speakers bureau: Novartis, Oliver Distler Grant/research support from: Grants/Research support from Actelion, Bayer, Boehringer Ingelheim, Competitive Drug Development International Ltd. and Mitsubishi Tanabe; he also holds the issued Patent on mir-29 for the treatment of systemic sclerosis (US8247389, EP2331143)., Consultant of: Consultancy fees from Actelion, Acceleron Pharma, AnaMar, Bayer, Baecon Discovery, Blade Therapeutics, Boehringer, CSL Behring, Catenion, ChemomAb, Curzion Pharmaceuticals, Ergonex, Galapagos NV, GSK, Glenmark Pharmaceuticals, Inventiva, Italfarmaco, iQvia, medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Roche, Sanofi and UCB, Speakers bureau: Speaker fees from Actelion, Bayer, Boehringer Ingelheim, Medscape, Pfizer and Roche, Mike-Oliver Becker: None declared

THU0331 INTERSTITIAL LUNG DISEASE IN SYSTEMIC SCLEROSIS: DECLINE IN FORCED VITAL CAPACITY DOES NOT PREDICT FURTHER PROGRESSION IN THE FOLLOWING PERIOD

Background:

In systemic sclerosis (SSc) patients with interstitial lung disease (ILD) approximately 30% show progressive ILD. It is unknown whether a progressive ILD period is followed by further lung function decline. In clinical practice, treatment is frequently initiated after observation of lung function decline over 6-12 months and lung function stabilization at follow up is often interpreted as treatment effect.

Objectives:

Assess the predictive ability of lung function decline over 12 months for further deterioration adjusted for known risk factors for ILD and treatment in two large and well characterized SSc cohorts.

Methods:

Patients with SSc-ILD by HRCT, fulfilling SSc classification criteria, from the Oslo and Zurich University Hospital were included. The first period with three consecutive annual forced vital capacity (FVC) measurements (i.e. at 0, 12 and 24 months, +/- 3 months) was used. Lung function decline was assessed by absolute changes in FVC% predicted. Moderately progressive ILD was defined as FVC decline of >5-<10% and significantly progressive ILD as FVC decline ≥10% in 12 months. Candidate predictors by experts (including SSc subtype, autoantibodies, disease duration, baseline and FVC decline in the first period, extent of lung and skin (mRSS) fibrosis, CRP, reflux, tendon friction rubs, O2 desaturation, dyspnea) for FVC decline in the second period were tested using logistic regression analysis. Treatment included low dose corticosteroids, mycophenolate mofetil; and other immunosuppressive treatment (cyclophosphamide, Rituximab and Tocilizumab).

Results:

In total, 240 SSc-ILD patients met the inclusion criteria (table). Of these 69 (29%) SSc-ILD patients showed progressive ILD in the first 12 months period; 34 (14%) with moderate (5-10%) and 35 (15%) with significant FVC decline (≥10%). Independent of FVC changes in the first period, 77 (32%) showed progressive ILD in the second period; 44 (18%) moderate and 33 (14%) significant FVC decline. Only 21 (9%) SSc-ILD patients had two progressive periods, and 115 (48%) were stable in the two 12 month’s periods; all independent of treatment. In multivariable logistic regression, progressive ILD in the first period (moderate, significant or combined FVC decline) was not predictive for progression in the following period. Of all applied risk factors, only mRSS was significantly predictive for further FVC decline, also when adjusted for age, gender and treatment (OR 1.03, 95%CI 1.00-1.08, p=0.035).

Conclusion:

Decline of FVC in one 12 months period did not predict further ILD progression in the following 12 months independent of treatment. These results have important clinical implications. Firstly, a decline of lung function in one period seems not to be the right indicator for initiating treatment. Secondly, stabilization of lung function under treatment initiated after ILD progression cannot necessarily be interpreted as a treatment response on the individual patient level.

Table:

First periodBoth periodsSSc-ILD (n=240)ILD progression (n=69)ILD progression (n=21)Stable ILD (n=115)Age, years (SD)48 (14.7)49 (13.8)50 (14.3)46 (15.3)Male, n (%)57 (24)18 (26)5 (24)27 (24)Disease duration yrs, mean (SD)10.2 (11.4)9.8 (10.2)8.8 (11.0)10.8 (12.3)Disease duration <3 years, n (%)68 (28)22 (32)8 (38)29 (25)Diffuse cutaneous SSc, n (%)95 (40)30 (44)11 (52)43 (27)Anti-topoisomerase I Ab, n (%)84 (35)27 (40)9 (43)42 (37)mRSS, mean (SD)10 (9.3)11 (10.2)16 (13.0)8 (8.3)CRPml, mean (SD)3.6 (7.2)3.3 (6.2)4.4 (9.1)3.1 (5.1)GERD, n (%)148 (62)44 (64)15 (74)70 (61)FVC % predicted90 (20.3)90 (21.9)92 (21.7)89 (19.3)DLCO% predicted64 (17.9)64 (16.6)70 (11.3)65 (17.5)Lung fibrosis >20%, n (%)55 (23)16 (23)4 (19)27 (24)Mycophenolate Mofetil, n (%)47 (20)15 (22)5 (24)23 (20)Other immunosuppression, n (%)79 (33)22 (32)9 (43)42 (37)Corticosteroids, n (%)62 (26)18 (26)8 (38)28 (24)

Disclosure of Interests:

Anna-Maria Hoffmann-Vold Grant/research support from: Boehringer Ingelheim, Consultant of: Boehringer Ingelheim, Actelion, Bayer, GlaxoSmithKline, Speakers bureau: Boehringer Ingelheim, Actelion, Roche, Håvard Fretheim: None declared, Britta Maurer Grant/research support from: AbbVie, Protagen, Novartis, congress support from Pfizer, Roche, Actelion, and MSD, Speakers bureau: Novartis, Mike Durheim Grant/research support from: BI, Consultant of: BI, Speakers bureau: BI, Øyvind Midtvedt: None declared, Mike O. Becker: None declared, Rucsandra Dobrota: None declared, Øyvind Molberg: None declared, Suzana Jordan: None declared, Oliver Distler Grant/research support from: Grants/Research support from Actelion, Bayer, Boehringer Ingelheim, Competitive Drug Development International Ltd. and Mitsubishi Tanabe; he also holds the issued Patent on mir-29 for the treatment of systemic sclerosis (US8247389, EP2331143)., Consultant of: Consultancy fees from Actelion, Acceleron Pharma, AnaMar, Bayer, Baecon Discovery, Blade Therapeutics, Boehringer, CSL Behring, Catenion, ChemomAb, Curzion Pharmaceuticals, Ergonex, Galapagos NV, GSK, Glenmark Pharmaceuticals, Inventiva, Italfarmaco, iQvia, medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Roche, Sanofi and UCB, Speakers bureau: Speaker fees from Actelion, Bayer, Boehringer Ingelheim, Medscape, Pfizer and Roche