Pulmonary complications: one of the most challenging complications of systemic sclerosis

Apical fibrosis was the most common incidental pulmonary finding in a familial Mediterranean fever cohort

INTRODUCTION

Familial Mediterranean fever (FMF) is one of the common autoinflammatory diseases with multisystemic manifestation. Pleuritis is the only known pulmonary involvement of FMF; however, as far as we know, thoracic involvements in pleural, parenchymal, bronchial, and vascular structures have not been evaluated yet.

METHOD

We included 243 consecutive FMF patients who applied to our clinic within the last 5 years and were requested to have a thorax CT for any reason and 122 trauma patients without any comorbidity. An experienced radiologist evaluated the thorax CT images blindly according to the relevant guidelines. We then presented the common incidental pulmonary and mediastinal findings on the thorax CT. Additionally, we compared patients with and without lung involvement according to demographic and disease-related parameters.

RESULTS

In our study, 167 of 243 patients (68.7%) had at least one of the pulmonary findings on their thorax CT. The most common pulmonary findings were apical fibrosis in 96 (39.5%) patients, parenchymal fibrotic changes in 48 (19.8%) patients, and a solitary parenchymal nodule smaller than 4 mm in 33 (13.6%) patients. All demographic, genetic, and disease-related characteristics, including the frequency of spondyloarthropathy, were similar in patients with and without pulmonary findings.

CONCLUSIONS

We showed that the most common incidental pulmonary finding in our FMF cohort was apical fibrosis on thoracic CT. Our data did not show causality between FMF and apical fibrosis; therefore, more studies are needed to evaluate the frequency and clinical significance of apical fibrosis in FMF. Key Points • More than two-thirds of familial Mediterranean fever (FMF) patients in our study group who underwent a thoracic scan for any reason had pulmonary and mediastinal findings on thorax computed tomography (CT). • In our FMF cohort, the most common incidental pulmonary finding on their thorax CT was apical fibrosis. • All demographic and disease-related characteristics, including the frequency of spondyloarthritis, were similar between patients with and without pulmonary and mediastinal findings.

PET/CT and inflammatory mediators in systemic sclerosis-associated interstitial lung disease

Objective:

To investigate the correlation of HRCT findings with pulmonary metabolic activity in the corresponding regions using ¹⁸F-FDG PET/CT and inflammatory markers in patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD).

Methods:

This was a cross-sectional study involving 23 adult patients with SSc-associated ILD without other connective tissue diseases. The study also involved ¹⁸F-FDG PET/CT, HRCT, determination of serum chemokine levels, clinical data, and pulmonary function testing.

Results:

In this cohort of patients with long-term disease (disease duration, 11.8 ± 8.7 years), a nonspecific interstitial pneumonia pattern was found in 19 (82.6%). Honeycombing areas had higher median standardized uptake values (1.95; p = 0.85). Serum levels of soluble tumor necrosis factor receptor 1, soluble tumor necrosis factor receptor 2, C-C motif chemokine ligand 2 (CCL2), and C-X-C motif chemokine ligand 10 were higher in SSc patients than in controls. Serum levels of CCL2-a marker of fibroblast activity-were correlated with pure ground-glass opacity (GGO) areas on HRCT scans (p = 0.007). ¹⁸F-FDG PET/CT showed significant metabolic activity for all HRCT patterns. The correlation between serum CCL2 levels and GGO on HRCT scans suggests a central role of fibroblasts in these areas, adding new information towards the understanding of the mechanisms surrounding cellular and molecular elements and their expression on HRCT scans in patients with SSc-associated ILD.

Conclusions:

¹⁸F-FDG PET/CT appears to be unable to differentiate the intensity of metabolic activity across HRCT patterns in chronic SSc patients. The association between CCL2 and GGO might be related to fibroblast activity in these areas; however, upregulated CCL2 expression in the lung tissue of SSc patients should be investigated in order to gain a better understanding of this association.

IL-13 and IL-33 Serum Levels Are Increased in Systemic Sclerosis Patients With Interstitial Lung Disease

Objective

Systemic sclerosis (SSc) mortality is extremely variable in its internal organ involvement. Pulmonary fibrosis occurs in up to 30% of the cases. Animal models provide evidence that IL-33 is able to induce both cutaneous and pulmonary fibrosis via increased IL-13 and in SSc patients the levels of IL-33 correlate with skin fibrosis. Our aim was to test whether both IL-33 and IL-13 are higher in patients with diffuse SSc and interstitial lung disease (SSc-ILD) compared to SSc patients without ILD and healthy controls.

Methods

Serum levels of IL-13 and IL-33 were measured in 30 SSc patients with diffuse disease and 30 healthy controls by enzyme-linked immunosorbent assay. The extent of pulmonary fibrosis was assessed according to HRCT Warrick score. Pulmonary function tests included lung diffusion capacity for carbon monoxide, forced vital capacity and total lung capacity.

Results

Both IL-13 and IL-33 levels were increased in SSc patients compared to controls and significantly associated each other. DLco, FVC and TLC scores were inversely associated with IL-33 and IL-13 levels. Both IL-33 and IL-13 levels were significantly associated with the Warrick severity score and higher in the group of SSc patients with reduced pulmonary function compared to SSc patients with normal pulmonary function tests.

Conclusion

The IL-13/IL-33 axis needs to be further explored in longitudinal studies of SSc-ILD patients to assess its validity as a biomarker and future treatment target, as does downstream mediator ST2.

Ongoing clinical trials and treatment options for patients with systemic sclerosis-associated interstitial lung disease

SSc is a rare CTD that affects multiple organ systems, resulting in substantial morbidity and mortality. Evidence of interstitial lung disease (ILD) is seen in ∼80% of patients with SSc. Currently there is no approved disease-modifying treatment for ILD and few effective treatment options are available. CYC is included in treatment guidelines, but it has limited efficacy and is associated with toxicity. MMF is becoming the most commonly used medication in clinical practice in North America and the UK, but its use is not universal. Newer agents targeting the pathogenic mechanisms underlying SSc-ILD, including fibrotic and inflammatory pathways, lymphocytes, cell-cell and cell-extracellular membrane interactions, hold promise for better treatment outcomes, including improved lung function, patient-related outcomes and quality of life. Here we review ongoing trials of established and novel agents that are currently recruiting patients with SSc-ILD.

Is heart transplantation a valuable option in patients with diffuse systemic sclerosis and primary cardiac involvement?

Systemic sclerosis patients with primary cardiac involvement can be reliably diagnosed by cardiac magnetic resonance imaging and are associated with a poor prognosis. This case report highlights the importance of considering heart transplantation in those patients as a lifesaving procedure.

A simplified lung ultrasound for the diagnosis of interstitial lung disease in connective tissue disease: a meta-analysis

Background

Interstitial lung disease (ILD) is a common complication of connective tissue disease (CTD) and a leading cause of morbidity and mortality. There are various lung ultrasound (LUS) scoring systems with different lung intercostal spaces (LIS). The purpose of this meta-analysis was to find a simplified LUS method for the assessment of CTD-ILD.

Methods

We systematically retrieved lung ultrasound diagnostic studies on CTD-ILD in PubMed, Embase, and Web of Science databases. Summary diagnostic accuracy, including sensitivity, specificity, and area under the curve (AUC), was analyzed. Subgroup analysis was conducted according to different LIS and diseases.

Results

The 11 studies included in this meta-analysis comprised a total of 487 patients with CTD. The pooled sensitivity and specificity of the LUS were 0.859 (95% confidence interval (CI) 0.812–0.898) and 0.839 (95% CI 0.782–0.886), respectively, illustrating its great value for CTD-ILD diagnosis. In addition, there were six methods to evaluate LIS, including 72, 65, 50, 14, 10, and all LIS. The pooled sensitivity and specificity of 14 LIS were 0.982 (95% CI 0.904–1.000) and 0.875 (95% CI 0.710–0.965), respectively. The pooled positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odd ratio (DOR) of 14 LIS were 7.297 (95% CI 6.050–17.45), 0.029 (95% CI 0.006–0.147), and 292.30 (95% CI 35.53–2403.8), respectively. Moreover, the AUC for systemic sclerosis (SSc) and rheumatoid arthritis (RA) was 0.929 and 0.981, respectively; the DOR for SSc and RA was 42.93 (95% CI 17.75–103.79) and 80.24 (95% CI 8.107–796.09), respectively.

Conclusions

We found a modified and simplified method of LUS, by scanning 14 LIS in a short time, which had a very high sensitivity and specificity.

Treatment of systemic sclerosis associated fibrotic manifestations: Current options and future directions

Systemic sclerosis (SSc) is a complicated multisystem disease which is characterized by the highest standardized mortality ratio among all systemic rheumatic diseases with no approved therapies so far. From a pathogenetic point of view it is generally considered that autoimmunity, vasculopathy and fibrosis are the main pathophysiologic processes. In this opinion article/minireview we will discuss current and future options for SSc-related fibrotic manifestations (skin thickening and lung fibrosis). Based on the results of SLS II the best treatment option for skin involvement in SSc is mycophenolate mofetil (MMF). Methotrexate (MTX) is another option which is safe and of low cost but evidence supporting its use is weak. The standard of care for SSc-ILD nowadays is MMF. Patients not responding to MMF could be treated with rituximab (RTX) or cyclophosphamide (CYC) (tocilizumab [TCZ] could be an option as well but only for patients with increased inflammatory markers). Hematopoietic stem cell transplantation (HSCT) could be considered in patients with severe/life-threatening disease who have failed conventional treatment. The most promising therapeutic approach currently been evaluated in phase 3 trials is probably the combination of MMF plus pirfenidone.

Mesenchymal stromal cells from human umbilical cord prevent the development of lung fibrosis in immunocompetent mice

Lung fibrosis is a severe condition resulting from several interstial lung diseases (ILD) with different etiologies. Current therapy of ILD, especially those associated with connective tissue diseases, is rather limited and new anti-fibrotic strategies are needed. In this study, we investigated the anti-fibrotic activity in vivo of human mesenchymal stromal cells obtained from whole umbilical cord (hUC-MSC). Adult immunocompetent C57BL/6 mice (n. = 8 for each experimental condition) were injected intravenously with hUC-MSC (n. = 2.5 × 10⁵) twice, 24 hours and 7 days after endotracheal injection of bleomycin. Upon sacrifice at days 8, 14, 21, collagen content, inflammatory cytokine profile, and hUC-MSC presence in explanted lung tissue were analyzed. Systemic administration of a double dose of hUC-MSC significantly reduced bleomycin-induced lung injury (inflammation and fibrosis) in mice through a selective inhibition of the IL6-IL10-TGFβ axis involving lung M2 macrophages. Only few hUC-MSC were detected from explanted lungs, suggesting a “hit and run” mechanism of action of this cellular therapy. Our data indicate that hUC-MSC possess strong in vivo anti-fibrotic activity in a mouse model resembling an immunocompetent human subject affected by inflammatory ILD, providing proof of concept for ad-hoc clinical trials.

Ultrasound B-lines in the evaluation of interstitial lung disease in patients with systemic sclerosis: Cut-off point definition for the presence of significant pulmonary fibrosis

The aim of this study was to establish the cut-off point of ultrasound (US) B-lines number for detecting the presence of significant interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) (SSc-ILD) in relation to high-resolution computed tomography (HRCT) findings.Consecutive SSc-ILD patients underwent chest HRCT, lung US (LUS), pulmonary function test, and clinical assessment. Exclusion criteria were represented by the presence of a coexisting congestive heart failure and a clinical history suggestive of lung or pleural diseases. HRCT images were scored for the presence of ILD by 2 readers, in accordance with the Warrick scoring system. US assessment was performed by a US skilled rheumatologist, blinded to HRCT results and clinical data, and included the bilateral evaluation of 14 lung intercostal spaces (LIS). In each LIS, the number of B-lines was recorded and summed. To test discriminant validity, we used the receiver operating characteristic (ROC) curve analysis applying a Warrick score of 7 as external criterion for the presence of SSc-ILD.Forty patients completed the study. The US B-lines number and the Warrick score confirmed excellent correlation (Spearman rho: 0.958, P = .0001). The ROC curve analysis revealed that the presence of 10 US B-lines is the cut-off point with the greatest positive likelihood ratio (12.52) for the presence of significant SSc-ILD.The detection of 10 B-lines is highly predictive for the HRCT presence of significant SSc-ILD. In SSc patients, the LUS assessment as first imaging tool may represent an effective model to improve the correct timing of chest HRCT.

Sirtuin1 Protects against Systemic Sclerosis-related Pulmonary Fibrosis by Decreasing Proinflammatory and Profibrotic Processes

Pulmonary fibrosis is the leading cause of death in systemic sclerosis (SSc). Sirtuin1 (SIRT1) is a deacetylase with known antiinflammatory and antifibrotic activity in the liver, kidney, and skin. The role of SIRT1 in SSc-related pulmonary fibrosis is unknown. In the present work, we determined that the expression of SIRT1 in peripheral blood mononuclear cells of patients with SSc with pulmonary fibrosis is lower than that in patients with SSc without pulmonary fibrosis. In in vivo studies of bleomycin-induced lung fibrosis in mice, SIRT1 activation with resveratrol reduced collagen production when it was administered either prophylactically during the inflammatory stage or after the development of fibrosis. Furthermore, SIRT1 activation or overexpression inhibited tumor necrosis factor-α-induced inflammatory responses in vitro in human fetal lung fibroblasts, depletion of SIRT1 in fibroblasts enhanced inflammation, and these effects were related to changes in the acetylation of NF-κB. In addition, SIRT1 activation or exogenous overexpression inhibited collagen production in vitro, and these manipulations also inhibited fibrosis via inactivation of transforming growth factor-β/mothers against decapentaplegic homolog and mammalian target of rapamycin signaling. Taken together, our results show that a loss of SIRT1 may participate in the pathogenesis of SSc-related pulmonary fibrosis, and that SIRT1 activation is an effective treatment for both the early (inflammatory) and late (fibrotic) stages of pulmonary fibrosis. Thus, SIRT1 may be a promising therapeutic target in the management of SSc-related pulmonary fibrosis.

[Pulmonary manifestations in collagen vascular diseases]

CLINICAL/METHODICAL ISSUE

Pulmonary complications are frequent in patients with collagen vascular diseases (CVD). Frequent causes are a direct manifestation of the underlying disease, side effects of specific medications and lung infections.

STANDARD RADIOLOGICAL METHODS

The standard radiological procedure for the work-up of pulmonary pathologies in patients with CVD is multidetector computed tomography (MDCT) with thin-slice high-resolution reconstruction.

PERFORMANCE

The accuracy of thin-slice CT for the identification of particular disease patterns is very high. The pattern of usual interstitial pneumonia (UIP) representing the direct pulmonary manifestation of rheumatoid arthritis (RA) can be identified with a sensitivity of 45 % and a specificity of 96 %.

ACHIEVEMENTS

Both direct pulmonary manifestations, drug-induced toxicity and certain infections can have a similar appearance in thin-slice MDCT in various forms of CVD. Knowledge of the patterns and causes contributes to the diagnostic certainty.

PRACTICAL RECOMMENDATIONS

At first diagnosis of a CVD and associated pulmonary symptoms thin-slice MDCT is recommended. Clinical, lung function and imaging follow-up examinations should be performed every 6-12 months depending on the results of the MDCT. In every case the individual CT morphological patterns of pulmonary involvement must be identified. The combination of information on the anamnesis, clinical and imaging results is a prerequisite for an appropriate disease management.

Predictors of lung function test severity and outcome in systemic sclerosis-associated interstitial lung disease

Systemic sclerosis-related interstitial lung disease (SSc-ILD) is the leading cause of death in SSc. In this study, we aimed to describe the baseline severity and evolution of forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO) in patients with SSc-ILD and to assess the baseline clinical, biological and high-resolution CT scan (HRCT) predictors of this evolution. Baseline and serial FVC and DLCO were collected in 75 SSc-ILD patients followed during 6.4±4.2 years (n = 557 individual data). FVC and DLCO evolution was modelled using a linear mixed model with random effect. During follow-up, FVC was stable while DLCO significantly decreased (-1.5±0.3%/year (p<0.0001). Baseline NYHA functional class III/IV, extensive SSc-ILD on HRCT and DLCO<80% were associated with a lower baseline FVC. Absence of digital ulcers extensive SSc-ILD, and FVC<80% and were associated with a lower baseline DLCO. Presence or history of digital ulcers and presence of pulmonary hypertension at baseline or during follow-up were associated with a faster decline of DLCO overtime. Neither age, gender, subtype of SSc nor specificity of autoantibodies were associated with baseline severity or outcome of lung function tests. In this SSc-ILD population, FVC was therefore stable while DLCO significantly declined over time. ILD extension was associated with baseline FVC and DLCO but not with their evolution. Presence or history of digital ulcers and pulmonary hypertension were predictors of a faster decline of DLCO over time.

Tomography patterns of lung disease in systemic sclerosis

Currently, lung impairment is the leading factor responsible for the morbidity and mortality associated with systemic sclerosis. Therefore, the recognition of the various tomography patterns becomes decisive in the clinical management of these patients. In high-resolution computed tomography studies, the most common pattern is that of nonspecific interstitial pneumonia. However, there are other forms of lung involvement that must also be recognized. The aim of this study was to review the literature on the main changes resulting from pulmonary involvement in systemic sclerosis and the corresponding radiological findings, considering the current classification of interstitial diseases. We searched the Medline (PubMed), Lilacs, and SciELO databases in order to select articles related to pulmonary changes in systemic sclerosis and published in English between 2000 and 2015. The pulmonary changes seen on computed tomography in systemic sclerosis are varied and are divided into three main categories: interstitial, alveolar, and vascular. Interstitial changes constitute the most common type of pulmonary involvement in systemic sclerosis. However, alveolar and vascular manifestations must also be recognized and considered in the presence of atypical clinical presentations and inadequate treatment responses.

Selecting registration schemes in case of interstitial lung disease follow-up in CT

PURPOSE

Primary goal of this study is to select optimal registration schemes in the framework of interstitial lung disease (ILD) follow-up analysis in CT.

METHODS

A set of 128 multiresolution schemes composed of multiresolution nonrigid and combinations of rigid and nonrigid registration schemes are evaluated, utilizing ten artificially warped ILD follow-up volumes, originating from ten clinical volumetric CT scans of ILD affected patients, to select candidate optimal schemes. Specifically, all combinations of four transformation models (three rigid: rigid, similarity, affine and one nonrigid: third order B-spline), four cost functions (sum-of-square distances, normalized correlation coefficient, mutual information, and normalized mutual information), four gradient descent optimizers (standard, regular step, adaptive stochastic, and finite difference), and two types of pyramids (recursive and Gaussian-smoothing) were considered. The selection process involves two stages. The first stage involves identification of schemes with deformation field singularities, according to the determinant of the Jacobian matrix. In the second stage, evaluation methodology is based on distance between corresponding landmark points in both normal lung parenchyma (NLP) and ILD affected regions. Statistical analysis was performed in order to select near optimal registration schemes per evaluation metric. Performance of the candidate registration schemes was verified on a case sample of ten clinical follow-up CT scans to obtain the selected registration schemes.

RESULTS

By considering near optimal schemes common to all ranking lists, 16 out of 128 registration schemes were initially selected. These schemes obtained submillimeter registration accuracies in terms of average distance errors 0.18 ± 0.01 mm for NLP and 0.20 ± 0.01 mm for ILD, in case of artificially generated follow-up data. Registration accuracy in terms of average distance error in clinical follow-up data was in the range of 1.985-2.156 mm and 1.966-2.234 mm, for NLP and ILD affected regions, respectively, excluding schemes with statistically significant lower performance (Wilcoxon signed-ranks test, p < 0.05), resulting in 13 finally selected registration schemes.

CONCLUSIONS

Selected registration schemes in case of ILD CT follow-up analysis indicate the significance of adaptive stochastic gradient descent optimizer, as well as the importance of combined rigid and nonrigid schemes providing high accuracy and time efficiency. The selected optimal deformable registration schemes are equivalent in terms of their accuracy and thus compatible in terms of their clinical outcome.

Imaging of pulmonary involvement in rheumatic disease

Lung disease commonly occurs in connective tissue diseases (CTD) and is an important cause of morbidity and mortality. Imaging is central to the evaluation of CTD-associated pulmonary complications. In this article, a general discussion of radiologic considerations is followed by a description of the pulmonary appearances in individual CTDs, and the imaging appearances of acute and nonacute pulmonary complications. The contribution of imaging to monitoring disease, evaluating treatment response, and prognostication is reviewed. Finally, we address the role of imaging in the challenging multidisciplinary evaluation of interstitial lung disease where there is an underlying suspicion of an undiagnosed CTD.

Update on biomarkers in systemic sclerosis: tools for diagnosis and treatment

Systemic sclerosis (SSc) is a complex autoimmune disease in which immune activation, vasculopathy, and extensive fibrosis of the skin and internal organs are among the principal features. SSc is a heterogeneous disease with varying manifestations and clinical outcomes. Currently, patients’ clinical evaluation often relies on subjective measures, non-quantitative methods, or requires invasive procedures as markers able to predict disease trajectory or response to therapy are lacking. Therefore, current research is focusing on the discovery of useful biomarkers reflecting ongoing inflammatory or fibrotic activity in the skin and internal organs, as well as being predictive of future disease course. Recently, remarkable progress has been made towards a better understanding of numerous mechanisms involved in the pathogenesis of SSc. This has opened new possibilities for the development of novel biomarkers and therapy. However, current proposed biomarkers that could reliably describe various aspects of SSc still require further investigation. This review will summarize studies describing the commonly used and validated biomarkers, the newly emerging and promising SSc biomarkers identified to date, and consideration of future directions in this field.

[Clinical value of surfactant protein D as a biomarker of pulmonary fibrosis in patients with scleroderma systematica in relation to the presence of gastroesophageal reflux]

AIM

To study the role of serum surfactant protein D (SP-D) as a biomarker of lung injury in scleroderma systematica (SDS) in relation to the presence of gastroesophageal reflux (GER).

SUBJECTS AND METHODS

Fifty-six patients (mean age 46±14 years) with diffuse and circumscribed SDS were examined and underwent pulmonary functional tests, X-ray and, if lung injury was present, high-resolution computed tomography of the lung, echocardiography, gastroduodenoscopy, and barium X-ray of the esophagus; an enzyme-linked immunosorbent assay was used to determine serum SP-D levels.

RESULTS

SP-D concentrations significantly correlate with the presence of lung injury in SDS and are significantly higher in the presence of pulmonary fibrosis and the signs of frosted glass and honeycomb lung patterns. SP-D levels were higher in the patients with lung injury and SDS in the group of those with pulmonary fibrosis and GER than in the group of pulmonary fibrosis patients without the latter.

CONCLUSION

Serum SP-D may be considered in a number of biomarkers for the severity of lung injury in SDS, including GER-associated lung injury.

The Role of PPAR Gamma in Systemic Sclerosis

Fibrosis is recognized as an important feature of many chronic diseases, such as systemic sclerosis (SSc), an autoimmune disease of unknown etiology, characterized by immune dysregulation and vascular injury, followed by progressive fibrosis affecting the skin and multiple internal organs. SSc has a poor prognosis because no therapy has been shown to reverse or arrest the progression of fibrosis, representing a major unmet medical need. Recently, antifibrotic effects of PPARγ ligands have been studied in vitro and in vivo and some theories have emerged leading to new insights. Aberrant PPARγ function seems to be implicated in pathological fibrosis in the skin and lungs. This antifibrotic effect is mainly related to the inhibition of TGF-β/Smad signal transduction but other pathways can be involved. This review focused on recent studies that identified PPARγ as an important novel pathway with critical roles in regulating connective tissue homeostasis, with emphasis on skin and lung fibrosis and its role on systemic sclerosis.

Automated 3D ιnterstitial lung disease εxtent quantification: performance evaluation and correlation to PFTs

In this study, the performance of a recently proposed computer-aided diagnosis (CAD) scheme in detection and 3D quantification of reticular and ground glass pattern extent in chest computed tomography of interstitial lung disease (ILD) patients is evaluated. CAD scheme performance was evaluated on a dataset of 37 volumetric chest scans, considering five representative axial anatomical levels per scan. CAD scheme reliability analysis was performed by estimating agreement (intraclass correlation coefficient, ICC) of automatically derived ILD pattern extent to semi-quantitative disease extent assessment in terms of 29-point rating scale provided by two expert radiologists. Receiver operating characteristic (ROC) analysis was employed to assess CAD scheme accuracy in ILD pattern detection in terms of area under ROC curve (A z ). Correlation of reticular and ground glass volumetric pattern extent to pulmonary function tests (PFTs) was also investigated. CAD scheme reliability was substantial for ILD extent (ICC = 0.809) and distinct reticular pattern extent (0.806) and moderate for distinct ground glass pattern extent (0.543), performing within inter-observer agreement. CAD scheme demonstrated high accuracy in detecting total ILD (A z  = 0.950 ± 0.018), while accuracy in detecting distinct reticular and ground glass patterns was 0.920 ± 0.023 and 0.883 ± 0.024, respectively. Moderate and statistically significant negative correlation was found between reticular volumetric pattern extent and diffusing capacity, forced expiratory volume in 1 s, forced vital capacity, and total lung capacity (R = -0.581, -0.513, -0.494, and -0.446, respectively), similar to correlations found between radiologists' semi-quantitative ratings with PFTs. CAD-based quantification of disease extent is in agreement with radiologists' semi-quantitative assessment and correlates to specific PFTs, suggesting a potential imaging biomarker for ILD staging and management.

[Use of pulmonary function tests and biomarkers studies to diagnose and follow-up interstitial lung disease in systemic sclerosis]

Interstitial lung disease (ILD) is becoming one of the main causes of death of patients with systemic sclerosis (SSc). The prevalence of ILD associated with SSc (SSc-ILD) varies from 33% to 100% according to diagnostic methods. Clinical features such as dyspnea on exertion, dry cough, and chest pains are not specific and usually late-appearing, implying more specific tests in the diagnostic, prognosis, and follow-up of ILD in patients with SSc. High resolution thoracic CT scanner (HRCT) is more sensitive than chest X-ray in the detection of SSc-ILD. Pulmonary function tests (PFT) are non-invasive and periodically used to assess the impacts of SSc on respiratory function. Diagnostic values of bronchoalveolar lavage and histological examination on lung biopsy are controversial. However, these techniques are essential for studying cellular and molecular mechanisms underlying the pathophysiology of SSc-ILD. Several biomarkers such as surfactant-A (SP-A), -D (SP-D), mucin-like high molecular weight glycoprotein (KL-6), and chemokine CCL-18 have been implicated in SSc-PID. Serum levels of these proteins are correlated with the severity of SSc-ILD, as assessed by HRCT and/or PFT. Finally, alveolar concentration of exhaled nitric oxide can be used to screen SSc patients with high risk of deterioration of respiratory function, in whom immunosuppressant treatment could be useful in preventing the evolution to irreversible lung fibrosis.

Early systemic sclerosis: marker autoantibodies and videocapillaroscopy patterns are each associated with distinct clinical, functional and cellular activation markers

INTRODUCTION

Early systemic sclerosis (SSc) is characterized by Raynaud's phenomenon together with scleroderma marker autoantibodies and/or a scleroderma pattern at capillaroscopy and no other distinctive feature of SSc. Patients presenting with marker autoantibodies plus a capillaroscopic scleroderma pattern seem to evolve into definite SSc more frequently than patients with either feature. Whether early SSc patients with only marker autoantibodies or capillaroscopic positivity differ in any aspect at presentation is unclear.

METHODS

Seventy-one consecutive early SSc patients were investigated for preclinical cardiopulmonary alterations. Out of these, 44 patients and 25 controls affected by osteoarthritis or primary fibromyalgia syndrome were also investigated for serum markers of fibroblast (carboxyterminal propeptide of collagen I), endothelial (soluble E-selectin) and T-cell (soluble IL-2 receptor alpha) activation.

RESULTS

Thirty-two of the 71 patients (45.1%) had both a marker autoantibody and a capillaroscopic scleroderma pattern (subset 1), 16 patients (22.5%) had only a marker autoantibody (subset 2), and 23 patients (32.4%) had only a capillaroscopic scleroderma pattern (subset 3). Patients with marker autoantibodies (n = 48, 67.6%) had a higher prevalence of impaired diffusing lung capacity for carbon monoxide (P = 0.0217) and increased serum levels of carboxyterminal propeptide of collagen I (P = 0.0037), regardless of capillaroscopic alterations. Patients with a capillaroscopic scleroderma pattern (n = 55, 77.5%) had a higher prevalence of puffy fingers (P = 0.0001) and increased serum levels of soluble E-selectin (P = 0.0003) regardless of marker autoantibodies.

CONCLUSION

These results suggest that the autoantibody and microvascular patterns in early SSc may each be related to different clinical-preclinical features and circulating activation markers at presentation. Longitudinal studies are warranted to investigate whether these subsets undergo a different disease course over time.

Systemic sclerosis and the risk of tuberculosis

OBJECTIVE

Pulmonary involvement is common in patients with systemic sclerosis (SSc), and this condition causes substantial morbidity and mortality. Disrupted immunity from the disease or associated medication may render such patients subject to tuberculosis (TB) infection. However, the relationship between SSc and TB has not yet been investigated.

METHODS

Using the Taiwan National Health Insurance Research Database, 838 patients with SSc diagnosed in Taiwan during 2000-2006 were identified and followed for emergence of TB infection. Incidence rate ratios (IRR) of TB compared to 8380 randomly selected age-, sex-, and comorbidity-matched controls without SSc were calculated. The Cox proportional hazards model was used for multivariate adjustment to identify independent risk factors for TB infection.

RESULTS

The risk of TB infection was higher in the SSc cohort than in controls (IRR 2.81, 95% CI 1.36-5.37; p = 0.004), particularly for pulmonary TB (IRR 2.53, 95% CI 1.08-5.30; p = 0.022). Other independent risk factors for TB infection in patients with SSc were age ≥ 60 years [hazard ratio (HR) 3.52, 95% CI 1.10-11.33; p = 0.035] and pulmonary hypertension (PH; HR 6.06, 95% CI 1.59-23.17; p = 0.008). Mortality did not differ for SSc patients with or without TB.

CONCLUSION

In this nationwide study, the incidence of TB infection was significantly higher among patients with SSc than in controls without SSc. Special care should be taken in managing patients with SSc who are at high risk for TB, especially those aged ≥ 60 years or who also have PH.

Scleroderma-related lung disease: are adipokines involved pathogenically?

Scleroderma is a systemic autoimmune disease of unknown etiology whose characteristic features include endothelial cell dysfunction, fibroblast proliferation, and immune dysregulation. Although almost any organ can be pathologically involved in scleroderma, lung complications including interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are the leading cause of death in patients with this condition. Currently, the molecular mechanisms leading to development of scleroderma-related lung disease are poorly understood; however, the systemic nature of this condition has led many to implicate circulating factors in the pathogenesis of some of its organ impairment. In this article we focus on a new class of circulating factors derived from adipose-tissue called adipokines, which are known to be altered in scleroderma. Recently, the adipokines adiponectin and leptin have been found to regulate biological activity in endothelial, fibroblast, and immune cell types in lung and in many other tissues. The pleiotropic nature of these circulating factors and their functional activity on many cell types implicated in the pathogenesis of ILD and PAH suggest these hormones may be mechanistically involved in the onset and/or progression of scleroderma-related lung diseases.

Treating CTDs related fibrotic ILDs by immunosuppressants: "facts and faults"

Fibrotic interstitial lung diseases (ILDs) are commonly encountered in scleroderma where they significantly influence prognosis. The mainstay of treatment in idiopathic fibrotic ILDs for the past 30 years was based on the combined administration of prednisone and cyclophosphamide (CYC) or prednisone, azathioprine plus N-acetyl cysteine, recently proved ineffective and harmful. Rheumatologists also despite "facts" showing that CYC treatment has no beneficial impact on fibrotic ILDs in scleroderma continue to commit the same, in a manner of speaking, "faults" by "treating their fibrotic ILDs by immunosuppressants." In this issue of the journal, Panopoulos et al. (Lung, 191, 483-489, 2013) recognizing the minimal effect of CYC on fibrotic ILDs in scleroderma patients and the increased use in clinical practice of mycophenolate mofetil (MMF) as an alternative, report that MMF use to replace CYC in this setting is not supported, confirming that restoration of purely fibrotic damage in the lungs remains one of the most challenging fields in medicine.

Carbohydrate antigen 15.3 as a serum biomarker of interstitial lung disease in systemic sclerosis patients

BACKGROUND

To determine the usefulness of Ca 15.3 as a candidate biomarker in systemic sclerosis (SSc) patients with interstitial lung disease (ILD).

METHODS

Two-hundred-twenty-one SSc patients with Ca 15.3 determinations were considered; 168 had evidence of interstitial lung involvement on high-resolution computed tomography (HRCT); digitalized scans were available for scoring in 84 subjects. Discrimination between patients with or without ILD, was assessed by receiving operating characteristics (ROC) analysis; correlations between HRCT scores and Ca 15.3 were performed. Survival and serial pulmonary function tasting (PFT) data were used for prognostication.

RESULTS

Ca 15.3 serum levels strongly correlated with HRCT scores (r=0.734, p<0.0001) which were predictors of survival at the 20% threshold (p=3.1∗10(-4)). Ca 15.3 had an area under ROC to detect the meaningful 20% fibrosis extent equal to 0.927 and abnormal Ca 15.3 values were capable of differentiating between patients at hi- or low-risk for progression in the group with undetermined disease extent (HR=3.209, confidence interval [CI95]=1.56-6.602, p=0.002). Ca 15.3 outperformed other PFT measures in providing a separation of survival estimates where HRCT scans are unavailable. The combined use of HRCT scores and Ca 15.3 in SSc-ILD patients was more discriminatory (HR=4.824, CI95=2.612-8.912, p<0.0001) than the staging system based on HRCT scores plus FVC (HR=2.657, CI95=1.703-4.147, p<0.0001) and characterized by lower prediction errors (0.2134 vs 0.2234).

CONCLUSION

Ca 15.3 is a rapid and inexpensive candidate biomarker for SSc-ILD being proportional to the extent of lung injury and specific and sensitive in assessing meaningful extents of the disease with prognostic significance.

Using cyclophosphamide in inflammatory rheumatic diseases

Cyclophosphamide (CYC), primarily introduced into clinical practice as an anti-cancer substance, is a potent immunosuppressive drug. Today, it is used in a number of organ- or life -threatening autoimmune diseases such as systemic vasculitides or connective tissue diseases. While being effective, CYC has a small therapeutic index and is associated with significant toxicity. CYC has been used in oncology in a variety of diseases and a lot of data has been derived from this area. This knowledge is often extrapolated to the rheumatologic settings. However, besides some similarities substantial differences between these two specialties considering the underlying diseases as well as the kind of application of the drug exist. The aim of the present review is to describe the general characteristics of the use of CYC from the rheumatologist's point of view, including pharmacologic and pharmacokinetic properties, drug interactions, toxicity and possible preventive and/or therapeutic measures; all of which are important to consider when using this particular drug in the treatment of inflammatory rheumatic diseases.

Interstitial lung disease in the connective tissue diseases

The connective tissue diseases (CTDs) are inflammatory, immune-mediated disorders in which interstitial lung disease (ILD) is common and clinically important. Interstitial lung disease may be the first manifestation of a CTD in a previously healthy patient. CTD-associated ILD frequently presents with the gradual onset of cough and dyspnea, although rarely may present with fulminant respiratory failure. Infection and drug reaction should always be ruled out. A diagnosis of idiopathic ILD should never be made without a careful search for subtle evidence of underlying CTD. Treatment of CTD-ILD typically includes corticosteroids and immunosuppressive agents.

Extent of disease on high-resolution computed tomography lung is a predictor of decline and mortality in systemic sclerosis-related interstitial lung disease

OBJECTIVES

In a multi-centre study, we sought to determine whether extent of disease on high-resolution CT (HRCT) lung, reported using a simple grading system, is predictive of decline and mortality in SSc-related interstitial lung disease (SSc-ILD), independently of pulmonary function tests (PFTs) and other prognostic variables.

METHODS

SSc patients with a baseline HRCT performed at the time of ILD diagnosis were identified. All HRCTs and PFTs performed during follow-up were retrieved. Demographic and disease-related data were prospectively collected. HRCTs were graded according to the percentage of lung disease: >20%: extensive; <20%: limited; unclear: indeterminate. Indeterminate HRCTs were converted to limited or extensive using a forced vital capacity threshold of 70%. The composite outcome variable was deterioration (need for home oxygen or lung transplantation), or death.

RESULTS

Among 172 patients followed for mean (s.d.) of 3.5 (2.9) years, there were 30 outcome events. In Weibull multivariable hazards regression modelling, baseline HRCT grade was independently predictive of outcome, with an adjusted hazard ratio (aHR) = 3.0, 95% CI 1.2, 7.5 and P = 0.02. In time-varying covariate models (based on 1309 serial PFTs and 353 serial HRCTs in 172 patients), serial diffusing capacity of the lung for carbon monoxide by alveolar volume ratio (ml/min/mmHg/l) (aHR = 0.4; 95% CI 0.3, 0.7; P = 0.001) and forced vital capacity (dl) (aHR = 0.9; 95% CI 0.8, 0.97; P = 0.008), were also strongly predictive of outcome.

CONCLUSION

Extensive disease (>20%) on HRCT at baseline, reported using a semi-quantitative grading system, is associated with a three-fold increased risk of deterioration or death in SSc-ILD, compared with limited disease. Serial PFTs are informative in follow-up of patients.

The promising role of lung ultrasound in systemic sclerosis

Ultrasound (US) has an emergent and relevant role in the assessment of systemic sclerosis (SSc) even if there are many fields and applications that still have not been sufficiently explored. In this review, we will report an update of the available data regarding the use of US in lung involvement that might cause disability and mortality in SSc patients. Lung US does not employ ionizing radiation and is more rapid and less expensive than traditional high-resolution tomography (HRCT). Furthermore, recent initial studies have demonstrated that US scores correlated to HRCT and functional respiratory test results in SSc interstitial lung disease. The research agenda for the future should include a more profound investigation of its specificity (comparison with healthy subjects and other diseases) and sensitivity to change at follow-up, to adequately disseminate its use in daily practice and clinical trials.

Ultrasound in the assessment of pulmonary fibrosis in connective tissue disorders: correlation with high-resolution computed tomography

OBJECTIVE

To investigate the correlation between ultrasound (US) B-lines and high-resolution computed tomography (HRCT) findings in the assessment of pulmonary fibrosis (PF) in patients with connective tissue disorders (CTD).

METHODS

Thirty-four patients with a diagnosis of CTD were included. Each patient underwent clinical examination, pulmonary function test (PFT), chest HRCT, and lung US by an experienced radiologist or rheumatologist. A second rheumatologist carried out US examinations to assess interobserver agreement. In each patient, US B-line lung assessment including 50 intercostal spaces (IS) was performed. For the anterior and lateral chest, the IS were the second to the fifth along the parasternal, mid-clavicular, anterior axillary, and medial axillary lines (the left fifth IS of the anterior and lateral chest was not performed because of the presence of the heart, which limits lung visualization). For the posterior chest, the IS assessed were the seventh to the eighth along the posterior-axillary and subscapular lines. The second to eighth IS were assessed in the paravertebral line. In each IS, the number of US B-lines under the transducer was recorded, summed, and graded according to the following semiquantitative scoring: grade 0 = normal (< 10 B-lines); grade 1 = mild (11 to 20 B-lines); grade 2 = moderate (21 to 50 B-lines); and grade 3 = marked (> 50 B-lines).

RESULTS

A total of 1700 IS in 34 patients were assessed. A significant linear correlation was found between the US score and the HRCT score (p < 0.001; correlation coefficient ρ = 0.875). A positive correlation was found between US B-line assessments and values of DLCO (p = 0.014). Both κ values and overall percentages of interobserver agreement showed excellent agreement.

CONCLUSION

Our study demonstrates that US B-line assessment may be a useful and reliable additional imaging method in the evaluation of PF in patients with CTD.

Thoracic manifestations of collagen vascular diseases

Collagen vascular diseases are a diverse group of immunologically mediated systemic disorders that often lead to thoracic changes. The collagen vascular diseases that most commonly involve the lung are rheumatoid arthritis, progressive systemic sclerosis, systemic lupus erythematosus, polymyositis and dermatomyositis, mixed connective tissue disease, and Sjögren syndrome. Interstitial lung disease and pulmonary arterial hypertension are the main causes of mortality and morbidity among patients with collagen vascular diseases. Given the broad spectrum of possible thoracic manifestations and the varying frequency with which different interstitial lung diseases occur, the interpretation of thoracic images obtained in patients with collagen vascular diseases can be challenging. The task may be more difficult in the presence of treatment-related complications such as drug toxicity and infections, which are common in this group of patients. Although chest radiography is most often used for screening and monitoring of thoracic alterations, high-resolution computed tomography can provide additional information about lung involvement in collagen vascular diseases and may be especially helpful for differentiating specific disease patterns in the lung. General knowledge about the manifestations of thoracic involvement in collagen vascular diseases allows radiologists to provide better guidance for treatment and follow-up of these patients.

Interferon and alternative activation of monocyte/macrophages in systemic sclerosis-associated pulmonary arterial hypertension

OBJECTIVE

To explore the relationship between biomarkers of pulmonary arterial hypertension (PAH), interferon (IFN)-regulated gene expression, and the alternative activation pathway in systemic sclerosis (SSc).

METHODS

Peripheral blood mononuclear cells (PBMCs) were purified from healthy controls, patients with idiopathic PAH, and SSc patients (classified as having diffuse cutaneous SSc, limited cutaneous SSc [lcSSc] without PAH, and lcSSc with PAH). IFN-regulated and "PAH biomarker" genes were compared after supervised hierarchical clustering. Messenger RNA levels of selected IFN-regulated genes (Siglec1 and MX1), biomarker genes (IL13RA1, CCR1, and JAK2), and the alternative activation marker gene (MRC1) were analyzed on PBMCs and on CD14- and CD14+ cell populations. Interleukin-13 (IL-13) and IL-4 concentrations were measured in plasma by immunoassay. CD14, MRC1, and IL13RA1 surface expression was analyzed by flow cytometry.

RESULTS

Increased PBMC expression of both IFN-regulated and biomarker genes distinguished SSc patients from healthy controls. Expression of genes in the biomarker cluster, but not in the IFN-regulated cluster, distinguished lcSSc with PAH from lcSSc without PAH. The genes CCR1 (P<0.001) and JAK2 (P<0.001) were expressed more highly in lcSSc patients with PAH compared with controls and mainly by CD14+ cells. MRC1 expression was increased exclusively in lcSSc patients with PAH (P<0.001) and correlated strongly with pulmonary artery pressure (r=0.52, P=0.03) and higher mortality (P=0.02). MRC1 expression was higher in CD14+ cells and was greatly increased by stimulation with IL-13. IL-13 concentrations in plasma were most highly increased in lcSSc patients with PAH (P<0.001).

CONCLUSION

IFN-regulated and biomarker genes represent distinct, although related, clusters in lcSSc patients with PAH. MRC1, a marker for the effect of IL-13 on alternative monocyte/macrophage activation, is associated with this severe complication and is related to mortality.

Right ventricular systolic pressure assessed by echocardiography: a predictive factor of mortality in patients with scleroderma

BACKGROUND

Pulmonary arterial hypertension (PAH) is a well-known complication of systemic sclerosis (SSc). Doppler echocardiographic screening for the detection of PAH (by measuring right ventricular systolic pressure [RVSP]) is therefore recommended for all patients with SSc. However, the validity of RVSP as a predictor of mortality in patients with SSc is not well established.

HYPOTHESIS

Doppler-determined PAH identifies a high-risk subset of patients with SSc with decreased survival.

METHODS

We performed echocardiography in 155 consecutive patients with SSc between May 2005 and July 2006 and tested the value of an RVSP level of ≥36 mm Hg to predict mortality. Cox proportional hazards model was used to examine the individual relationship between each variable and the mortality rate.

RESULTS

Tricuspid regurgitant jets for RVSP determination were quantified in 129 patients (82.6%), of which 47 (36.4%) had RVSP ≥36 mm Hg. The median follow-up time was 34 months. The 1-, 2-, and 3-year survival rates were significantly lower among SSc patients with RVSP ≥36 vs ≤36 mm Hg (82%, 78%, and 67% vs 98%, 90%, and 86%, respectively, P < 0.01 by Wilcoxon test). In a multivariate analysis including echocardiographic and clinical variables, only an RVSP ≥36 mm Hg and a New York Heart Association III/IV class were associated with increased mortality; the respective Cox hazard ratios were 2.22 (95% confidence interval [CI]: 1.01-4.89, P = 0.048) and 4.77 (95% CI: 2.09-10.90, P = 0.000).

CONCLUSIONS

Our results indicate that Doppler RVSP identifies a high-risk subset and supports the use of Doppler RVSP as a screening test in patients with SSc who may warrant early treatment of their PAH.

The short-term role of corticosteroid therapy for pulmonary arterial hypertension associated with connective tissue diseases: report of five cases and a literature review

Pulmonary arterial hypertension (PAH) is a life-threatening complication in connective tissue diseases (CTD). It remains controversial whether immunosuppressive therapy is useful for PAH associated with CTD (PAH-CTD). The Dana Point algorithm does not refer such treatments in patients with PAH-CTD due to the lack of evidence. However, some case reports have shown the potential efficacy of immunosuppression for PAH-CTD. Here we report five cases of PAH-CTD treated with corticosteroids and discuss the current management of PAH-CTD with immunosuppressive agents. Our cases consisted of three active systemic lupus erythematosus (SLE), a quiescent SLE and an active polymyositis. WHO functional classes at baseline were class III in three cases and class II in two. Median follow-up period was 44 (28-92) weeks. PAH was diagnosed by right heart catheterization in all cases (median pulmonary arterial pressure was 45 (29-49) mmHg). All patients received 1 mg/kg of prednisolone (PSL) for 2-4 weeks, followed by appropriate dose reduction. Methylprednisolone pulse therapy was performed in patients resistant to the high dosage of PSL. Four patients received vasodilators in combination. The therapy as above improved WHO functional class 4 weeks after the initiation of PSL in all the patients. Two patients required dose increase or additional administration of vasodilators due to the dose reduction of PSL. Corticosteroid therapy may be effective for PAH-CTD at least in the short term, even in low general activity of CTD or moderate PAH. Our experience suggests that corticosteroid therapy, by itself or in conjunction with standard vasodilators, is effective for PAH-CTD patients.

Efficacy of cyclophospamide in the treatment of interstitial lung disease associated with systemic sclerosis

BACKGROUND

Cyclophosphamide (CYC) stabilizes the parameters of lung function tests (LFT) of patients with (SSc) and interstitial lung disease (ILD) treated for 12 months. There is little information about long-term treatment (24 months). The aim of this study is to analyze the effect of intravenous CYC in LFT parameters in patients with SSc and ILD treated for 24 months.

PATIENTS AND METHOD

Retrospective study of 37 patients with ILD associated with scleroderma treated with intravenous CYC for 24 months and regularly assessed by LFT (at baseline, 6, 12 and 24 months) including forced vital capacity (FVC) and transfer capacity of carbon monoxide (DL(CO)). To evaluate response to treatment the recommendations of the ATS and SEPAR were considered.

RESULTS

The difference between FVC and DL(CO) values performed at baseline and those performed at 6, 12, and 24 months were less than 10%, which meant that CYC stabilized LFT. There were no differences in LFT when patients treated for 6 months were evaluated according to the type of skin involvement of the SSc (diffuse or limited) and the duration of the ILD. Although patients with severe restriction (FVC<70%) showed more improvement, it was less than 10% in all cases.

CONCLUSION

In this series of patients with ILD associated with SSc intravenous CYC was effective in stabilizing LFT in long-term treatment.

Immunology of fibrotic lung disease: managing infections whilst preventing autoimmunity?

Interstitial lung disease (ILD) and lung fibrosis are characterized by different grades of fibrosis and inflammation. Persistent low-grade inflammation is believed to play a major pathogenic role, leading to an imbalance of cytokines, growth factors, and tissue proteinases. Recruited monocytes and macrophages play a pivotal role through their cytokine expression and possibly differentiation into fibrocytes, pericytes, or myofibroblasts. Atypical bacterial infections can cause ILD, although not usually in the form of usual interstitial pneumonia. On the other hand, bacterial colonization is frequently encountered in patients with chronic fibrotic lung disorders, and patients regularly undergo antibacterial treatment. As demonstrated in patients with diffuse panbronchiolitis and other chronic respiratory disorders, treatment with macrolides can be beneficial. This is partly explained by their antimicrobial effects but, for macrolides, immunomodulatory properties have been identified which might also be beneficial in patients with ILD or lung fibrosis. This article reviews the immunology of lung fibrogenesis and putative implications of macrolides for reinstallation of tolerance.