Predictors of lung function decline in scleroderma-related interstitial lung disease based on high-resolution computed tomography: implications for cohort enrichment in systemic sclerosis-associated interstitial lung disease trials

Prevalence of the limited vs. extensive scleroderma-related interstitial lung disease at the time of diagnosis of SSc-ILD based on Goh et al. criteria. Systematic review and meta-analysis

INTRODUCTION

Goh et al. proposed in 2008 a classificatory algorithm of limited or extensive SSc-ILD. The prevalence of both at the time of diagnosis of SSc-ILD is not known with exactitude.

METHODS

The review was undertaken by means of MEDLINE and SCOPUS from 2008 to 2023 and using the terms: "systemic", "scleroderma" or "interstitial lung disease" [MesH]. The Newcastle-Ottawa Scale was used for the qualifying assessment for observational studies and the Jadad scale for clinical trials. The inverse variance-weighted method was performed.

RESULTS

Twenty-seven studies were initially included in the systematic review and meta-analysis (SRMA). Of these, 17 studies had no overlapping data. They reported data from 2,149 patients, 1,369 (81.2%) were female. The mean age was 52.4 (SD 6.6) years. 45.2% of the patients had the diffuse subtype and 54.8% had the limited or sine scleroderma subtype. A total of 38.7% of the patients showed positive antitopoisomerase antibodies (ATA) and 14.2% positive anticentromere antibodies (ACA). The mean percentage of forced vital capacity (FVC) at baseline was 80.5% (SD 6.9) and of diffusing capacity of the lungs for carbon monoxide (DLco) was 59.1% (SD 9.6). Twelve studies presented SSc-ILD extension data adjusted for PFTs and were included in the meta-analysis. The 10 observational cohort studies were analyzed separately. The overall percentage of limited extension was estimated at 63.5% (95%CI 55.3-73; p < 0.001) using the random-effects model. Heterogeneity between studies (I2) was 9.8% (95%CI 0-68.2%) with the random-effects model. Extensive pulmonary involvement was estimated at 34.3% (95%CI 26-45.4; p < 0.001). Heterogeneity between studies (I2) was 0% (95%CI 0-61.6%) with the random-effects model.

CONCLUSION

The overall percentage of limited SSc-ILD at the time of diagnosis of SSc-ILD was estimated at 63.5% and extensive at 34.3%.

CT evaluation of interstitial lung disease related to systemic sclerosis: visual versus automated assessment. A systematic review

AIM

To identify similarities and differences between visual (VA) and automated assessment (AA) of systemic sclerosis-related interstitial lung disease (SSc-ILD) at chest computed tomography (CT) in terms of clinical applicability.

MATERIALS AND METHODS

Medline, Embase, and Web of Science were searched to identify all studies investigating VA and AA for SSc-ILD assessment, from inception to 31 July 2022. Exclusion criteria were manuscripts not in English, absence of full-text, reviews, diseases other than ILD in SSc, CT not analysed with both VA and AA, VA and AA not adopted for the same purpose or not compared, overlap syndromes, SSc-ILD data not extractable, and studies with <10 patients.

RESULTS

Ten full-text studies (804 patients) were included. The most adopted VAs were the Warrick or Goh score (four studies each), while densitometry (eight studies) or lung texture analysis (LTA, two studies) were utilised as AAs. The main field of investigation was the correlation with baseline pulmonary function tests (PFT, six studies). Warrick VA showed lower correlations compared to densitometry, while Goh VA demonstrated more heterogeneous results. Compared to LTA, Goh VA obtained lower correlations with lung volumes but similar or stronger coefficients with alveolar diffusibility.

CONCLUSIONS

VA and AA may show heterogeneous results comparing their correlations with PFT, probably depending on the specific analysis adopted for each method. More data are needed on VA versus LTA. Comparisons between VA and AA regarding correlation with PFT follow-up and as prognostic elements, or for disease monitoring, are lacking. AAs in progressive fibrosis diagnosis remain to be tested.

Prognostic and predictive markers of systemic sclerosis-associated interstitial lung disease in a clinical trial and long-term observational cohort

OBJECTIVES

To explore prognostic and predictive markers of SSc-associated interstitial lung disease (SSc-ILD) outcomes in a phase 3 trial (focuSSced) and prognostic markers in a real-world cohort (SMART).

METHODS

The focuSSced SSc-ILD subgroup included 68 of 106 placebo-treated and 68 of 104 tocilizumab-treated patients. The SMART cohort included 505 patients with SSc-ILD. Linear mixed-effect models were used to identify factors associated with change in forced vital capacity (FVC). Kaplan-Meier estimation and Cox regression were used for time-to-event analyses.

RESULTS

In placebo-treated focuSSced patients, sex was a significant prognostic factor for FVC decline; males had increased risk for absolute decline ≥10% in percent-predicted FVC (ppFVC) and 0.22% faster weekly FVC decline than females (P = 0.0001). FVC was 9.8% lower in patients with CRP >6 mg/ml vs those with CRP ≤6 mg/ml (P = 0.0059). Tocilizumab reduced the risk for ≥10% decline in ppFVC in patients who were male, had earlier disease (<2 years duration), had IL-6 levels <10 pg/ml, or had anti-topoisomerase antibodies (ATA). In the SMART cohort, prognostic factors for ppFVC <70% were male sex, ATA, and low baseline FVC. Males had 3.3% lower FVC 1 year after disease onset (P < 0.001) and 0.6% faster yearly decline (P = 0.03) than females.

CONCLUSION

Prognostic markers in SSc-ILD were similar between focuSSced and SMART. Male sex and inflammatory markers were associated with lower FVC but IL-6 ≥10 pg/ml was not predictive of response to tocilizumab.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02453256.

Heterogeneity of determining disease severity, clinical course and outcomes in systemic sclerosis-associated interstitial lung disease: a systematic literature review

Objective The course of systemic sclerosis-associated interstitial lung disease (SSc-ILD) is highly variable and different from continuously progressive idiopathic pulmonary fibrosis (IPF). Most proposed definitions of progressive pulmonary fibrosis or SSc-ILD severity are based on the research data from patients with IPF and are not validated for patients with SSc-ILD. Our study aimed to gather the current evidence for severity, progression and outcomes of SSc-ILD.Methods A systematic literature review to search for definitions of severity, progression and outcomes recorded for SSc-ILD was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in Medline, Embase, Web of Science and Cochrane Library up to 1 August 2023.Results A total of 9054 papers were reviewed and 342 were finally included. The most frequent tools used for the definition of SSc-ILD progression and severity were combined changes of carbon monoxide diffusing capacity (DLCO) and forced vital capacity (FVC), isolated FVC or DLCO changes, high-resolution CT (HRCT) extension and composite algorithms including pulmonary function test, clinical signs and HRCT data. Mortality was the most frequently reported long-term event, both from all causes or ILD related.Conclusions The studies presenting definitions of SSc-ILD 'progression', 'severity' and 'outcome' show a large heterogeneity. These results emphasise the need for developing a standardised, consensus definition of severe SSc-ILD, to link a disease specific definition of progression as a surrogate outcome for clinical trials and clinical practice.PROSPERO registration number CRD42022379254.Cite Now.

Enrichment strategies for clinical trials targeting skin fibrosis and interstitial lung disease in systemic sclerosis

PURPOSE OF REVIEW

This review gives an update on enrichment strategies for clinical trials in patients with systemic sclerosis (SSc) in two contexts - skin fibrosis in early diffuse cutaneous disease, and SSc-related interstitial lung disease (ILD) - focusing on reports from the last 18 months. Lessons have been learnt from recent studies, making this review timely.

RECENT FINDINGS

Recent trials have highlighted how patients included into trials must be carefully selected to include 'progressors', that is, those most likely to benefit from treatment, and how drug mechanism action of action will influence trial design. For skin fibrosis, current enrichment strategies are mainly on clinical grounds (including disease duration, extent of skin thickening, tendon friction rubs and anti-RNA polymerase III positivity). Gene expression signatures may play a role in the future. For ILD, current enrichment strategies (degree of lung involvement as assessed by pulmonary function and high-resolution computed tomography) may help to recruit the most informative patients, but should avoid being too stringent to be feasible or for findings to be generalizable.

SUMMARY

Both skin fibrosis and ILD trials are challenging in SSc. Ongoing work on enrichment strategies should help to differentiate effective new treatments from placebo with smaller sample sizes than have been included in recent studies.

Weak to no correlation between quantitative high-resolution computed tomography metrics and lung function change in fibrotic diseases

Background

Identifying systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF) patients at risk of more rapid forced vital capacity (FVC) decline could improve trial design. The purpose of the present study was to explore the prognostic value of quantitative high-resolution computed tomography (HRCT) metrics derived by Imbio lung texture analysis (LTA) tool in predicting FVC slope.

Methods

This retrospective study used data from patients who were not treated with investigational drugs with and without background antifibrotic therapies in tocilizumab phase 3 SSc, lebrikizumab phase 2 IPF, and zinpentraxin alfa phase 2 IPF studies conducted from 2015 to 2021. Controlled HRCT axial volumetric multidetector computed tomography scans were evaluated using the Imbio LTA tool. Associations between HRCT metrics and FVC slope were assessed through the Spearman correlation coefficient and adjusted R2 in a linear regression model adjusted by demographics and baseline clinical characteristics.

Results

A total of 271 SSc and IPF patients were analysed. Correlation coefficients of highest magnitude were observed in the SSc study between the extent of ground glass, normal volume, quantification of interstitial lung disease, reticular pattern, and FVC slope (-0.25, 0.28, -0.28, and -0.33, respectively), while the correlation coefficients observed in IPF studies were in general <0.2. The incremental prognostic value of the baseline HRCT metrics was marginal after adjusting baseline characteristics and was inconsistent across study arms.

Conclusion

Data from the SSc and IPF studies suggested weak to no and inconsistent correlation between quantitative HRCT metrics derived by the Imbio LTA tool and FVC slope in the studied SSc and IPF population.

Recent innovations in the screening and diagnosis of systemic sclerosis-associated interstitial lung disease

INTRODUCTION

Interstitial lung disease (ILD) is the leading cause of mortality in patients with systemic sclerosis (SSc). Risk of developing progressive ILD is highest among patients with diffuse cutaneous disease, positive anti-topoisomerase I antibody, and elevated acute phase reactants. With the FDA approval of two medications and a pipeline of novel therapeutics in trials, early recognition and intervention is critical. High-resolution computed tomography of the chest is the current gold standard test for diagnosis of ILD. Yet, it is not offered as a screening tool to all patients due to which ILD can be missed in up to a third of patients. There is a need to develop and validate more innovative screening modalities.

AREAS COVERED

In this review, we provide an overview of screening and diagnosis of SSc-ILD, highlighting the recent innovations particularly the role of soluble serologic, radiomic (quantitative lung imaging, lung ultrasound), and breathomic (exhaled breath analysis) biomarkers in the early detection of SSc-ILD.

EXPERT OPINION

There is remarkable progress in the development of new radiomics and serum biomarkers in diagnosing SSc-ILD. There is an urgent need for conceptualizing and testing composite ILD screening strategies that incorporate these biomarkers.

Study the Relationship of MDCT Staging in Disease Extent with the Systemic Sclerosis Disease Parameters

BACKGROUND AND OBJECTIVES

The highest incidence of death in systemic sclerosis due to pulmonary disease raises the need for early detection and treatment. The study aim is the assessment of interstitial pulmonary disease by Multi Detector High Resolution CT (MDCT) and finds its relationship with the other disease parameters and the Pulmonary Function tests (PFT).

PATIENTS AND METHODS

A prospective cross-sectional study was performed in Assiut University Hospitals from May 2018 to January 2020 and included 62 consecutive SSc female patients. Demographic, clinical, Laboratory, PFT and MDCT assessment were conducted for all participants.

RESULTS

The coarseness of fibrosis was 8.32 (range 0.0-17), the average proportion of ground-glass opacification was 28.3% (range, 0.0%-75%). Honey-comb pattern was seen in (52.5%). Mean Extent of disease was 46.25±3.7 (range 5-81). Restrictive deficit found in 42 patients. Significant relation was found between the extent of disease and the percentage predicted FVC (r=0.373, p 0.018) and FEV1/FVC (r=0.593, p 0.000) and coarseness of fibrosis and proportion of ground glass opacification correlated inversely with VC (r=-0.385, p=0.014, r=-0.376, p=0.017 respectively), Rayanud's phenomena, modified Rodnan Skin Score and Medsger's general are positively correlated with MDCT disease extent.

CONCLUSION

Scoring of systemic sclerosis (SSc) related interstitial lung disease (SSc-ILD) could be applicable as one of the important tools for disease assessment.

Automated quantification system predicts survival in rheumatoid arthritis-associated interstitial lung disease

OBJECTIVE

The prognosis of RA-associated interstitial lung disease (RA-ILD) is difficult to predict because of the variable clinical course. This study aimed to determine the prognostic value of an automated quantification system (AQS) in RA-ILD.

METHODS

We retrospectively analysed the clinical data and high-resolution CT (HRCT) images of 144 patients with RA-ILD. Quantitative lung fibrosis (QLF, sum of reticulation and traction bronchiectasis) and ILD [QILD; sum of QLF, honeycombing (QHC), and ground-glass opacity (QGG)] scores were measured using the AQS.

RESULTS

The mean age was 61.2 years, 43.8% of the patients were male, and the 5-year mortality rate was 30.5% (median follow-up, 52.2 months). Non-survivors showed older age, higher ESR and greater AQS scores than survivors. In multivariable Cox analysis, higher QLF, QHC and QILD scores were independent prognostic factors along with older age and higher ESR. In receiver-operating characteristic curve analysis, the QLF score showed better performance in predicting 5-year mortality than the QHC and QGG scores but was similar to the QILD score. Patients with high QLF scores (≥12% of total lung volume) showed higher 5-year mortality (50% vs 17.4%, P < 0.001) than those with low QLF scores and similar survival outcome to patients with idiopathic pulmonary fibrosis (IPF). Combining with clinical variables (age, ESR) further improved the performance of QLF score in predicting 5-year mortality.

CONCLUSION

QLF scores might be useful for predicting prognosis in patients with RA-ILD. High QLF scores differentiate a poor prognostic phenotype similar to IPF.

Profibrotic Role of Inducible Heat Shock Protein 90α Isoform in Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune disease that affects skin and multiple internal organs. TGF-β, a central trigger of cutaneous fibrosis, activates fibroblasts with the involvement of the stress-inducible chaperone heat shock protein 90 isoform α (Hsp90α). Available evidence supports overexpression and secretion of Hsp90α as a feature in profibrotic pathological conditions. The aim of this work is to investigate the expression and function of Hsp90α in experimental models of skin fibrosis such as human fibroblasts, C57BL/6 mice, and in human SSc. For this purpose, we generated a new experimental model based on doxorubicin administration with improved characteristics with respect to the bleomycin model. We visualized disease progression in vivo by fluorescence imaging. In this work, we obtained Hsp90α mRNA overexpression in human skin fibroblasts, in bleomycin- and doxorubicin-induced mouse fibrotic skin, and in lungs of bleomycin- and doxorubicin-treated mice. Hsp90α-deficient mice showed significantly decreased skin thickness compared with wild-type mice in both animal models. In SSc patients, serum Hsp90α levels were increased in patients with lung involvement and in patients with the diffuse form of SSc (dSSc) compared with patients with the limited form of SSc. The serum Hsp90α levels of patients dSSc were correlated with the Rodnan score and the forced vital capacity variable. These results provide new supportive evidence of the contribution of the Hsp90α isoform in the development of skin fibrosis. In SSc, these results indicated that higher serum levels were associated with dSSc and lung fibrosis.

The disconnect between visual assessment of air trapping and lung physiology for assessment of small airway disease in scleroderma-related interstitial lung disease: An observation from the Scleroderma Lung Study II Cohort

OBJECTIVE

To explore the presence of small airway disease (SAD) and emphysema in scleroderma-related interstitial lung disease (SSc-ILD) and to evaluate the physiologic and clinical correlates of SAD in SSc-ILD.

METHODS

Thoracic high-resolution computed tomography (HRCT) images obtained from the Scleroderma Lung Study II (SLSII) participants were reviewed by a group of thoracic radiologists. The presence of SAD was assessed by visual assessment for air trapping. HRCT scans were also evaluated for the presence of emphysema. The association of the presence of air trapping and emphysema with physiological measures of airway disease and clinical variables was evaluated.

RESULTS

A total of 155 baseline HRCT scans were reviewed. For assessment of air trapping, images needed to be adequate end-expiratory examinations, leaving 123 scans. Air trapping was seen in 13/123 (10.6%) of the SSc-ILD cohort and was independent of smoking history, asthma or the presence of gastroesophageal reflux. Air trapping on HRCT was not associated with physiologic evidence of SAD. We also identified 8/155 (5.2%) patients with emphysema on HRCT, which was independent of SAD and found mostly in prior smokers.

CONCLUSION

We report the first study of air trapping on standardized, high-quality HRCT images as a reflection of SAD in a relatively large, well characterized SSc-ILD cohort. The presence of SAD in non-smoking SSc-ILD patients supports that SSc may cause not only restrictive lung disease (SSc-ILD), but also, to a lesser extent, obstructive disease. Physiologic measures alone may be inadequate to detect airway disease in patients with SSc-ILD.

Idiopathic Pulmonary Fibrosis (an Update) and Progressive Pulmonary Fibrosis in Adults: An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline

Background: This American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana de Tórax guideline updates prior idiopathic pulmonary fibrosis (IPF) guidelines and addresses the progression of pulmonary fibrosis in patients with interstitial lung diseases (ILDs) other than IPF. Methods: A committee was composed of multidisciplinary experts in ILD, methodologists, and patient representatives. 1) Update of IPF: Radiological and histopathological criteria for IPF were updated by consensus. Questions about transbronchial lung cryobiopsy, genomic classifier testing, antacid medication, and antireflux surgery were informed by systematic reviews and answered with evidence-based recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. 2) Progressive pulmonary fibrosis (PPF): PPF was defined, and then radiological and physiological criteria for PPF were determined by consensus. Questions about pirfenidone and nintedanib were informed by systematic reviews and answered with evidence-based recommendations using the GRADE approach. Results:1) Update of IPF: A conditional recommendation was made to regard transbronchial lung cryobiopsy as an acceptable alternative to surgical lung biopsy in centers with appropriate expertise. No recommendation was made for or against genomic classifier testing. Conditional recommendations were made against antacid medication and antireflux surgery for the treatment of IPF. 2) PPF: PPF was defined as at least two of three criteria (worsening symptoms, radiological progression, and physiological progression) occurring within the past year with no alternative explanation in a patient with an ILD other than IPF. A conditional recommendation was made for nintedanib, and additional research into pirfenidone was recommended. Conclusions: The conditional recommendations in this guideline are intended to provide the basis for rational, informed decisions by clinicians.

Early Radiographic Progression of Scleroderma: Lung Disease Predicts Long-term Mortality

BACKGROUND

Radiographic end points commonly are included in therapeutic trials for systemic sclerosis (SSc)-interstitial lung disease (ILD); however, the relationship between these outcomes and long-term mortality is unclear.

RESEARCH QUESTION

Do short-term changes in radiographic measures of ILD predict long-term survival in patients with SSc?

STUDY DESIGN AND METHODS

The Scleroderma Lung Study (SLS) I and II evaluated the safety and efficacy of cyclophosphamide (in SLS I and II) and mycophenolate mofetil (in SLS II) for the treatment of SSc-ILD. Changes in the extent of ILD over time were assessed on high-resolution CT scans of the chest by quantitative image analysis, an approach that applies a computer-based algorithm to assess changes in the radiographic extent of ILD objectively. Participants subsequently were followed for up to 12 years (SLS I) and 8 years (SLS II). Cox proportional hazards models determined whether the change in the quantitative radiographic extent of ILD predicted survival, adjusting for other known predictors of survival.

RESULTS

Among SLS I and II participants, 82 and 90 had follow-up imaging scans, respectively, and were included in the analysis. Participants in both trials who showed an increase in the total quantitative radiographic extent of ILD scores of ≥ 2% at 12 months (SLS I) or 24 months (SLS II) experienced significantly worse long-term survival than those with change scores of < 2% (P ≤ .01, log-rank test). In the multivariate Cox models, radiographic progression remained associated with worse long-term survival in SLS I (P = .089) and SLS II (P = .014).

INTERPRETATION

Data from two independent clinical trial cohorts with extensive long-term follow-up demonstrated that radiographic progression of ILD over 12 to 24 months, in both treatment and placebo arms, can predict increased risk for long-term mortality in patients with SSc. These findings suggest that radiographic end points may serve as surrogates for mortality in SSc-ILD.

Quantitative evaluation of disease severity in connective tissue disease-associated interstitial lung disease by dual-energy computed tomography

Background

High-resolution computed tomography (HRCT) is recommended diagnosing and monitoring connective tissue disease-associated interstitial lung disease (CTD-ILD). Quantitative computed tomography has the potential to precisely assess the radiological severity of CTD-ILD, but has still been under study.

Objective

To investigate whether dual-energy computed tomography (DECT), a novel quantitative technique, can be used for quantitative severity assessment in CTD-ILD.

Methods

This cross sectional study recruited adult CTD-ILD patients who underwent DECT scans from the ICE study between October 2019 and November 2021. DECT parameters, including effective atomic number (Z_eff), lung (lobe) volume, and monochromatic CT number (MCTN) of each lung lobe, were evaluated. CTD-ILD was classified into extensive CTD-ILD and limited CTD-ILD by staging algorithm using combined forced vital capacity (FVC)%predicted and total extent of ILD (TEI) on CT. Dyspnea, cough, and life quality were scored by Borg dyspnea score, Leicester cough questionnaire (LCQ), and short-form 36 health survey questionnaire (SF-36), respectively.

Results

There was a total of 147 patients with DECT scans enrolled. Higher Z_eff value (3.104 vs 2.256, p < 0.001), higher MCTN (− 722.87 HU vs − 802.20 HU, p < 0.001), and lower lung volume (2309.51cm³ vs 3475.21cm³, p < 0.001) were found in extensive CTD-ILD compared with limited CTD-ILD. DECT parameters had significant moderate correlations with FVC%predicted (|r|= 0.542–0.667, p < 0.01), DLCO%predicted (|r|= 0.371–0.427, p < 0.01), and TEI (|r|= 0.485–0.742, p < 0.01). Receiver operating characteristic (ROC) analysis indicated MCTN averaged over the whole lung had the best performance for extensive CTD-ILD discrimination (AUC = 0.901, cut-off: − 762.30 HU, p < 0.001), with a sensitivity of 82.1% and a specificity of 85.4%. The Z_eff value was the independent risk factor for dyspnea (OR = 3.644, 95% CI: 1.846–7.192, p < 0.001) and cough (OR = 3.101, 95% CI: 1.528–6.294, p = 0.002), and lung volume significantly contributed to the mental component summary (MCS) in SF-36 (standardized β = 0.198, p < 0.05).

Conclusions

DECT can be applied to evaluate the severity of CTD-ILD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01972-4.

Pleuroparenchymal fibroelastosis in systemic sclerosis-associated interstitial lung disease

BACKGROUND

To explore the frequency and clinical associations of radiologic pleuroparenchymal fibroelastosis (PPFE) in patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD).

METHODS

In this single-center retrospective study, high resolution computed tomography (HRCT) images of 105 patients with SSc-ILD were examined for the presence of PPFE. Demographic, clinical, laboratory, and pulmonary function test (PFT) data of patients with and without PPFE were compared.

RESULTS

PPFE was detected in 19 (18.1%) patients ('definite PPFE' in 13 and 'consistent with PPFE' in 6 patients). Patients with PPFE had higher age and longer disease duration than PPFE (-) patients (p < 0.05 for both). Radiologic usual interstitial pneumoniae (UIP) pattern was more frequent (26.3% vs. 4.7%, p = 0.01) and median force vital capacity (FVC) was lower in patients with PPFE (64% vs. 82%, p = 0.005). Spontaneous pneumothorax developed in one patient with PPFE. More deaths occured in PPFE (+) group during follow-up (31% vs. 11%, p = 0.04).

Computed Tomography Predictors of Mortality or Disease Progression in Systemic Sclerosis–Interstitial Lung Disease: A Systematic Review

Objective

Although interstitial lung disease (ILD) is a major cause of morbidity and mortality in systemic sclerosis (SSc), its prognostication remains challenging. Given that CT represents the gold standard imaging technique in ILD assessment, a systematic review on chest CT findings as predictors of mortality or ILD progression in SSc-ILD was performed.

Materials and Methods

Three databases (Medline, Embase, and Web of Science) were searched to identify all studies analyzing CT mortality or ILD progression predictors in SSc-ILD, from inception to December 2020. ILD progression was defined by worsening of forced vital capacity and/or CT ILD findings. Manuscripts not written in English, with not available full-text, not focusing on SSc-ILD or with SSc-ILD not extrapolated, otherwise with overlap syndromes, pediatric patients, <10 cases or predictors other than CT features were excluded.

Results

Out of 3,513 citations, 15 full-texts (2,332 patients with SSc-ILD) met the inclusion criteria. ILD extent and extensive ILD, ILD densitometric analysis parameters, fibrotic extent and reticulation extent resulted as independent mortality predictors. Extensive ILD is also an independent predictor of death, need for supplemental oxygen or lung transplantation. Honeycombing extent is an independent risk factor for respiratory mortality. Independent predictors of ILD progression were not identified.

Conclusions

ILD extent and extensive ILD independently predict mortality in SSc-ILD on CT, as well as ILD densitometric analysis, fibrotic extent and reticulation extent. Extensive ILD is also a predictor of death, need for supplemental oxygen, or lung transplantation. Honeycombing extent predicts respiratory mortality. CT predictors of ILD progression need to be further investigated.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, PROSPERO, identifier: CRD420202005001.

Linagliptin ameliorates pulmonary fibrosis in systemic sclerosis mouse model via inhibition of endothelial-to-mesenchymal transition

Systemic sclerosis (SSc) is a connective tissue disease that often causes pulmonary fibrosis. Dipeptidyl peptidase 4 (DPP4) inhibitor has shown anti-fibrotic properties in various fibrotic diseases. However, only two studies have reported its anti-fibrosis effects in pulmonary fibrosis, and the mechanism is not completely clear. In the present study, we further investigated the protective effects of linagliptin, a highly specific DPP4 inhibitor, on pulmonary fibrosis in SSc mouse model and the potential mechanisms. The results showed that linagliptin ameliorated pulmonary fibrosis in SSc mouse model, as evidenced by improved pathological changes of lung and body weight loss induced by BLM. Linagliptin also reduced BLM-induced oxidative stress, inflammation in lung in vivo. We revealed that linagliptin attenuated BLM-induced endothelial-to-mesenchymal transition (EndMT) in vitro and in vivo. BLM-induced enhanced migration ability of endothelial cells was also alleviated by linagliptin. Moreover, we confirmed that the Akt/mammalian target of rapamycin pathway was involved in BLM-induced EndMT in vivo, which was suppressed by linagliptin. In summary, we further confirmed the therapeutic effects of linagliptin on pulmonary fibrosis in SSc mouse model, which is based on its inhibitory effects on EndMT, oxidative stress, and inflammation.

C-reactive protein and ground-glass opacity as predictors for intractable interstitial lung disease in patients with systemic sclerosis under cyclophosphamide treatment regardless of concomitant glucocorticoids

OBJECTIVES

Cyclophosphamide (CYC) has been proposed as a standard induction regimen for interstitial lung disease (ILD) associated with systemic sclerosis (SSc). However, there remain patients with SSc-ILD who are intractable to the therapy. This study aimed to identify factors associated with inadequate response to CYC and investigate how to treat SSc-ILD, especially in the need for glucocorticoids (GCs) combined with CYC.

METHODS

This retrospective study included consecutive patients diagnosed with SSc-ILD and treated with CYC between 2009 and 2020. Logistic regression models were used to determine the prognostic factors indicating significant progression of ILD (SP-ILD). The clinical findings of patients treated with vs. without GCs were compared.

RESULTS

Nineteen patients were registered, with a median age of 61.0 years. Fifteen were females, and five were classified into SP-ILD. Baseline high C-reactive protein (CRP) levels and non-widespread or localized ground-glass opacities (GGOs) predicted SP-ILD in multivariable analyses, and the cut-off level of CRP was 0.41 mg/dL. In clinical courses, SSc-ILD with high inflammation temporarily responded to CYC, regardless of the combined use of GCs; however, the therapeutic effects deteriorated soon after stopping CYC.

CONCLUSION

High CRP levels with non-widespread GGO predicted progressive ILD in patients with SSc treated with CYC.

Diagnosis and monitoring of systemic sclerosis-associated interstitial lung disease using high-resolution computed tomography

Patients with systemic sclerosis are at high risk of developing systemic sclerosis–associated interstitial lung disease. Symptoms and outcomes of systemic sclerosis–associated interstitial lung disease range from subclinical lung involvement to respiratory failure and death. Early and accurate diagnosis of systemic sclerosis–associated interstitial lung disease is therefore important to enable appropriate intervention. The most sensitive and specific way to diagnose systemic sclerosis–associated interstitial lung disease is by high-resolution computed tomography, and experts recommend that high-resolution computed tomography should be performed in all patients with systemic sclerosis at the time of initial diagnosis. In addition to being an important screening and diagnostic tool, high-resolution computed tomography can be used to evaluate disease extent in systemic sclerosis–associated interstitial lung disease and may be helpful in assessing prognosis in some patients. Currently, there is no consensus with regards to frequency and scanning intervals in patients at risk of interstitial lung disease development and/or progression. However, expert guidance does suggest that frequency of screening using high-resolution computed tomography should be guided by risk of developing interstitial lung disease. Most experienced clinicians would not repeat high-resolution computed tomography more than once a year or every other year for the first few years unless symptoms arose. Several computed tomography techniques have been developed in recent years that are suitable for regular monitoring, including low-radiation protocols, which, together with other technologies, such as lung ultrasound and magnetic resonance imaging, may further assist in the evaluation and monitoring of patients with systemic sclerosis–associated interstitial lung disease. A video abstract to accompany this article is available at: https://www.globalmedcomms.com/respiratory/Khanna/HRCTinSScILD

Anti-Ro/SS-A Antibody is Associated with Worse Pulmonary Outcome and Reduced Overall Survival in Systemic Sclerosis

OBJECTIVE

We sought to determine the association of anti-Ro/SS-A antibody with organ involvement and disease outcome, in patients with systemic sclerosis (SSc).

METHODS

A retrospective, long-term study of a cohort of incident patients diagnosed with SSc, and continuously followed at our rheumatology clinic during 1990-2018.

RESULTS

Included were 105 patients with known anti-Ro/SS-A antibody status, 92.4% female, mean age at diagnosis 52.0±15.6 years, and median follow-up 10 years; 64% were diagnosed with limited cutaneous SSc, 18% with diffuse cutaneous SSc, and 18% had SSc siné scleroderma or undetermined disease type. Anti-Ro/SS-A antibody tested positive in 21% of patients. In univariate analysis, anti-Ro/SS-A antibody-positivity was significantly associated with SSc overlap with Sjogren's syndrome (p <0.001). Pulmonary function tests (PFT) deterioration at last encounter was significantly associated with anti-Ro/SS-A antibody-positivity. In multivariate regression for anti-Ro/SS-A antibody-positive SSc patients and disease outcome (adjusted for age>50 years, smoking, and baseline predicted forced vital capacity (pFVC) < 80%), positive anti-Ro/SS-A antibody was significantly associated with higher all-cause mortality rate (HR 5.17, CI 95% 1.18-22.67, p=0.029), and greater deterioration of pFVC defined as decrement of last available pFVC compared to first available pFVC of ≥10% (HR 3.65, CI 95% 1.07-12.38, p=0.038).

CONCLUSIONS

Anti-Ro/SS-A antibody is an independent risk factor for worse pulmonary outcome and higher all-cause mortality in patients with SSc, independent of SSc clinical and/or serological subtype.

Increased Red Blood Cell Distribution Width in the First Year after Diagnosis Predicts Worsening of Systemic Sclerosis-Associated Interstitial Lung Disease at 5 Years: A Pilot Study

The course of systemic sclerosis-associated interstitial lung disease (SSc-ILD) varies among individuals. Red blood cell distribution width (RDW) has been reported to be a predictor of idiopathic pulmonary fibrosis. However, there are no studies on the relationship between RDW and SSc-ILD. We conducted a retrospective study of 28 patients who were diagnosed with SSc-ILD on their first visit to our hospital and were followed-up for 5 years. The correlation between the changes in RDW, KL-6, and SP-D (ΔRDW, ΔKL-6, ΔSP-D) and the changes in percent-predicted forced lung volume and % carbon monoxide diffusion (Δ%FVC, Δ%DLco) was investigated. ΔRDW at 1 year after diagnosis was significantly inversely correlated with Δ%FVC at 5 years after diagnosis (r = -0.51, p < 0.001) and Δ%DLco at 5 years after diagnosis (r = -0.47, p < 0.001), whereas ΔKL-6 and ΔSP-D at 1 year were not correlated with Δ%FVC or Δ%DLco at 5 years. In the group of SSc-ILD patients with RDW increase in the first year after diagnosis, %FVC and %DLco were significantly lower than baseline at 3-, 4-, and 5-year assessments. In the group of patients without RDW increase in the first year, %FVC and %DLco did not decrease during the follow-up period. In conclusion, the changes in RDW in the first year after diagnosis may be useful surrogate markers to predict the long-term course of SSc-ILD.

Outcome measurement instrument selection for lung physiology in systemic sclerosis associated interstitial lung disease: A systematic review using the OMERACT filter 2.1 process

OBJECTIVE

The Outcome Measures in Rheumatology (OMERACT) is a research organization focused on improving health care outcomes for patients with autoimmune and musculoskeletal diseases. The Connective Tissue Disease-Interstitial Lung Disease (CTD-ILD) Working Group on Lung Physiology is a group within OMERACT charged with identifying outcome measures that should be implemented in studies of patients with CTD-ILD. The OMERACT Filter 2.1 is an evidence-based algorithm used to identify outcome measures that are truthful, feasible, and able to discriminate between groups of interest. Our objective was to summate evidence (published literature, key opinion leader input, patient perspectives) that would influence the CTD-ILD Working Group's vote to accept or reject the use of two measures of lung physiology, the forced vital capacity (FVC) and the diffusion capacity of carbon monoxide (DLco) for use in randomized controlled trials (RTCs) and longitudinal observational studies (LOSs) involving patients with systemic sclerosis associated ILD (SSc-ILD).

METHODS

Patient Research Partners (those afflicted with SSc-ILD) and the CTD-ILD Working Group on Lung Physiology were polled to assess their opinion on the FVC and DLco in terms of feasibility; the CTD-ILD Working Group was also queried on these instruments' face and content validity. We then conducted a systematic literature review to identify articles in the SSc-ILD population that assessed the following measurement properties of FVC and DLco: (1) construct validity, (2) test-retest reliability, (3) longitudinal construct validity, (4) clinical trial discrimination/sensitivity to detect change in clinical trials, and (5) thresholds of meaning. Results were summarized in a Summary of Measurement Properties (SOMP) table for each instrument. OMERACT CTD-ILD Working Group members discussed and voted on the strength of evidence supporting these two instruments and voted to endorse, provisionally endorse, or not endorse either instrument.

RESULTS

Forty Patient Research Partners reported these two measures are feasible (are not an unnecessary burden or represent an infeasible longitudinal assessment of their disease). A majority of the 18 CTD-ILD Working Group members voted that both the FVC and DLco are feasible and have face and content validity. The systematic literature review returned 1,447 non-duplicated articles, of which 177 met eligibility for full text review. Forty-eight studies (13 RCTs, 35 LOSs) were included in the qualitative analysis. The FVC SOMP table revealed high quality, consistent data with evidence of good performance for all five measurement properties, suggesting requisite published evidence to proceed with endorsement. The DLco SOMP table showed a lack of data to support test-retest reliability and inadequate evidence to support clinical trial discrimination. There was unanimous agreement (15 [100%]) among voting CTD-ILD Working Group members to endorse the FVC as an instrument for lung physiology in RCTs and LOSs in SSc-ILD. Based on currently available evidence, DLco did not meet the OMERACT criteria and is not recommended for use in RCTs to represent lung physiology of SSc-ILD. The OMERACT Technical Advisory Group agreed with these decisions.

CONCLUSION

The OMERACT Filter 2.1 was successfully applied to the domain of lung physiology in patients with SSc-ILD. The FVC was endorsed for use in RCTs and LOSs based on the Working Group's vote; DLco was not endorsed.

High-Resolution Computed Tomography: Lights and Shadows in Improving Care for SSc-ILD Patients

The diagnosis and classification of systemic sclerosis-associated interstitial lung disease (SSc-ILD) is essential to improve the prognosis of systemic sclerosis (SSc) patients. The risk-stratification of disease severity and follow-up requires a multidisciplinary approach, integrating high-resolution computed tomography (HRTC) of the lung, pulmonary function tests (PFT), along with clinical and symptomatic evaluations. The use of HRCT in detecting SSc-ILD is not so much based on a definitive validation, but rather reflects the widespread clinician recognition of dissatisfaction with other modalities. However, due to the heterogeneity of SSc-ILD and the potential absence of symptoms in early or mild disease, it is prudent to consider as many parameters as possible in the assessment and monitoring of newly diagnosed patients. An early diagnosis meets the primary goal, i.e., the prevention of disease progression. The current first line treatment regimens are mainly centered on immunosuppressive therapy. This review assesses the role HRCT plays in optimizing care and improving clinical outcomes in SSc-ILD patients.

Tocilizumab Prevents Progression of Early Systemic Sclerosis-Associated Interstitial Lung Disease

OBJECTIVE

Tocilizumab (TCZ) has demonstrated lung function preservation in 2 randomized controlled trials in early systemic sclerosis (SSc). This effect has yet to be characterized in terms of radiographically evident quantitative lung involvement. We undertook this study to assess the impact of TCZ on lung function preservation in a post hoc analysis, stratifying treatment arms according to the degree of lung involvement.

METHODS

The focuSSced trial was a phase III randomized placebo-controlled trial of TCZ in patients with SSc and progressive skin disease. Participants underwent baseline and serial spirometry along with high-resolution chest computed tomography at baseline and at week 48. Quantitative interstitial lung disease (QILD) and fibrosis scores were assessed by computer software. We classified QILD into the following categories of lung involvement: mild (>5-10%), moderate (>10-20%), and severe (>20%).

RESULTS

Of 210 participants recruited for the trial, 136 patients (65%) had ILD. The majority of these patients (77%) had moderate-to-severe involvement (defined as >10% lung involvement). The TCZ arm demonstrated preservation of forced vital capacity percent predicted (FVC%) over 48 weeks (least squares mean change in FVC% = -0.1) compared to placebo (-6.3%). For mild, moderate, and severe QILD, the mean ± SD change in FVC% in the TCZ arm at 48 weeks were -4.1 ± 2.5% (n = 11), 0.7 ± 1.9% (n =19), and 2.1 ± 1.6% (n = 26), respectively, and in the placebo group were -10.0 ± 2.6% (n = 11), -5.7 ± 1.6% (n = 26), and -6.7 ± 2.0% (n = 16), respectively. Similar treatment-related preservation findings were seen independent of fibrosis severity.

CONCLUSION

TCZ in early SSc-associated ILD with progressive skin disease stabilized FVC% over 48 weeks, independent of the extent of radiographically evident QILD.

Study the Relationship of MDCT Staging in Disease Extent with the Systemic Sclerosis Disease Parameters

BACKGROUND AND OBJECTIVES

The highest incidence of death in systemic sclerosis due to pulmonary disease raises the need for early detection and treatment. The study aim is the assessment of interstitial pulmonary disease by Multi Detector High Resolution CT (MDCT) and finds its relationship with the other disease parameters and the Pulmonary Function tests (PFT).

PATIENTS AND METHODS

A prospective cross-sectional study was performed in Assiut University Hospitals from May 2018 to January 2020 and included 62 consecutive SSc female patients. Demographic, clinical, Laboratory, PFT and MDCT assessment were conducted for all participants.

RESULTS

The coarseness of fibrosis was 8.32 (range 0.0-17), the average proportion of ground-glass opacification was 28.3% (range, 0.0%-75%). Honey-comb pattern was seen in (52.5%). Mean Extent of disease was 46.25±3.7 (range 5-81). Restrictive deficit found in 42 patients. Significant relation was found between the extent of disease and the percentage predicted FVC (r=0.373, p 0.018) and FEV1/FVC (r=0.593, p 0.000) and coarseness of fibrosis and proportion of ground glass opacification correlated inversely with VC (r=-0.385, p=0.014, r=-0.376, p=0.017 respectively), Rayanud's phenomena, modified Rodnan Skin Score and Medsger's general are positively correlated with MDCT disease extent.

CONCLUSION

Scoring of systemic sclerosis (SSc) related interstitial lung disease (SSc-ILD) could be applicable as one of the important tools for disease assessment.

18F-FDG positron emission tomography scanning in systemic sclerosis-associated interstitial lung disease: a pilot study

Background

Interstitial lung disease is a common complication of systemic sclerosis (SSc-ILD), and it remains difficult to accurately predict its course. Progressing ILD could be more metabolically active, suggesting that the ¹⁸F-FDG tracer could be a tool in the managing of SSc-ILD.

Methods

In our center, SSc patients and controls (non-Hodgkin lymphoma cured after first-line regimen) who had received a PET/CT were screened retrospectively. The FDG uptake (visual intensity, pattern, SUV_max) was systematically recorded in > 30 regions of interest (ROIs) linked to SSc in a blind reviewing by 2 independent nuclear medicine physicians using a standardized form.

Results

Among the 545 SSc patients followed up in our center, 36, including 22 SSc-ILDs, had a PET/CT, whose indication was cancer screening in most cases. The mean ± SD age was 57.9 ± 13.0 years with 20/36 females. Fourteen patients had a disease duration of less than 2 years. A third had anti-centromere antibodies and 27.8% had anti-topoisomerase antibodies. Pulmonary FDG uptakes were higher in SSc patients than in controls (n = 89), especially in those with ILD compared with those without ILD. Pulmonary FDG uptakes were positively correlated with the ILD severity (fibrosis extent, %FVC, and %D_LCO). No significant difference was found in the FDG uptakes from extrathoracic ROIs. Progressing SSc-ILDs within the 2 years after PET/CT (n = 9) had significant higher pulmonary FDG uptakes at baseline than stable SSc-ILDs (n = 13).

Conclusion

PET/CT could be a useful tool in the assessment of the severity and the prediction of pulmonary function outcome of SSc-ILD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02460-8.

Large-Scale Characterization of Systemic Sclerosis Serum Protein Profile: Comparison to Peripheral Blood Cell Transcriptome and Correlations With Skin/Lung Fibrosis

OBJECTIVE

To provide a large-scale assessment of serum protein dysregulation in diffuse cutaneous systemic sclerosis (dcSSc) and to investigate serum protein correlates of SSc fibrotic features.

METHODS

We investigated serum protein profiles of 66 participants with dcSSc at baseline who were enrolled in the Scleroderma: Cyclophosphamide or Transplant Trial and 66 age- and sex-matched healthy control subjects. A panel of 230 proteins, including several cytokines and chemokines, was investigated. Whole blood gene expression profiling in concomitantly collected samples was performed.

RESULTS

Among the participants with dcSSc, the mean disease duration was 2.3 years. All had interstitial lung disease (ILD), and none were being treated with immunosuppressive agents at baseline. Ninety proteins were differentially expressed in participants with dcSSc compared to healthy control subjects. Similar to previous global skin transcript results, hepatic fibrosis, granulocyte and agranulocyte adhesion, and diapedesis were the top overrepresented pathways. Eighteen proteins correlated with the modified Rodnan skin thickness score (MRSS). Soluble epidermal growth factor receptor was significantly down-regulated in dcSSc and showed the strongest negative correlation with the MRSS, being predictive of the score's course over time, whereas α₁ -antichymotrypsin was significantly up-regulated in dcSSc and showed the strongest positive correlation with the MRSS. Furthermore, higher levels of cancer antigen 15-3 correlated with more severe ILD, based on findings of reduced forced vital capacity and higher scores of disease activity on high-resolution computed tomography. Only 14 genes showed significant differential expression in the same direction in serum protein and whole blood RNA gene expression analyses.

CONCLUSION

Diffuse cutaneous SSc has a distinct serum protein profile with prominent dysregulation of proteins related to fibrosis and immune cell adhesion/diapedesis. The differential expression for most serum proteins in SSc is likely to originate outside the peripheral blood cells.

Systemic Sclerosis and Pulmonary Disease

Systemic sclerosis is a complex, often progressive, multisystem autoimmune disease. It is commonly categorized into limited cutaneous or diffuse cutaneous systemic sclerosis. There is near universal involvement of skin fibrosis and gastrointestinal dysfunction, but lung disease is not only common but also a most serious complication. Severe lung disease is the top cause of mortality, displacing scleroderma renal crisis as the leading cause of death. Whether there is limited cutaneous or diffuse cutaneous manifestations can be predictive of what type of lung disease that can present in the patient. Limited cutaneous systemic sclerosis patients tend to have pulmonary hypertension whereas diffuse cutaneous systemic sclerosis patients tend to have interstitial lung disease. There are more rare phenotypes associated with antibodies Th/To and U3RNP that can have both pulmonary hypertension and interstitial lung disease concomitantly. There are inherent challenges in the management for both pulmonary hypertension and interstitial lung disease but with the focus on early diagnosis for each of these lung complications, treatment may have a higher chance of efficacy.

Assessment of recent evidence for the management of patients with systemic sclerosis-associated interstitial lung disease: a systematic review

This systematic review summarises current evidence to help guide treatment decisions for patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD). A systematic search of the literature (January 2012 to April 2018), including grey literature (searched between 1992 and 2011), was conducted using multiple electronic databases. Guidelines, meta-analyses, randomised controlled trials and observational studies reporting on risk stratification, screening, diagnosis, treatment and management outcomes for patients with SSc-ILD were included. A quality assessment of the included evidence was undertaken. In total, 2464 publications were identified and 280 included. Multiple independent risk factors for ILD in patients with SSc were identified, including older age, male sex and baseline pulmonary function. High-resolution computed tomography (HRCT) has been used for characterising ILD in patients with SSc, and pulmonary function tests are a key adjunctive component in the diagnostic and monitoring pathway. The clinical value of biomarkers relating to SSc-ILD diagnosis or assessment for disease progression is unknown at present. Immunosuppressive therapy (monotherapy or combined therapy) is the current standard of care for SSc-ILD; long-term evidence for effective and safe treatment of SSc-ILD is limited. Identification of patients at risk for SSc-ILD remains challenging. HRCT and pulmonary function tests are key to diagnosing and monitoring for disease progression. Although immunosuppressive therapy is considered current first-line treatment, it is partly associated with adverse effects and long-term follow-up evidence is limited. Novel therapies and biomarkers should be further explored in well-controlled clinical studies.

Diagnosis and management of connective tissue disease-associated interstitial lung disease in Australia and New Zealand: A position statement from the Thoracic Society of Australia and New Zealand

Pulmonary complications in CTD are common and can involve the interstitium, airways, pleura and pulmonary vasculature. ILD can occur in all CTD (CTD-ILD), and may vary from limited, non-progressive lung involvement, to fulminant, life-threatening disease. Given the potential for major adverse outcomes in CTD-ILD, accurate diagnosis, assessment and careful consideration of therapeutic intervention are a priority. Limited data are available to guide management decisions in CTD-ILD. Autoimmune-mediated pulmonary inflammation is considered a key pathobiological pathway in these disorders, and immunosuppressive therapy is generally regarded the cornerstone of treatment for severe and/or progressive CTD-ILD. However, the natural history of CTD-ILD in individual patients can be difficult to predict, and deciding who to treat, when and with what agent can be challenging. Establishing realistic therapeutic goals from both the patient and clinician perspective requires considerable expertise. The document aims to provide a framework for clinicians to aid in the assessment and management of ILD in the major CTD. A suggested approach to diagnosis and monitoring of CTD-ILD and, where available, evidence-based, disease-specific approaches to treatment have been provided.

Expert Perspectives On Clinical Challenges: Expert Perspectives: Challenges in Scleroderma

You are consulted to evaluate a 56-year-old woman with known Raynaud's phenomenon, finger swelling of several; months' duration, and new hypertension with a blood pressure of 160/100 mm/Hg. She also reports progressive shortness of breath. Physical examination reveals telangiectasias, sclerodactyly, and proximal skin sclerosis (thick shiny skin on the chest and upper arms), and bibasilar crackles are found on chest examination. Laboratory tests reveal evidence of microangiopathic hemolytic anemia, thrombocytopenia, and elevation of the serum creatinine level (previously normal), and chest computed tomography shows evidence of ground-glass opacification in both lower lung fields.

Etiology, Risk Factors, and Biomarkers in Systemic Sclerosis with Interstitial Lung Disease

Systemic sclerosis (SSc) is a complex, multiorgan, autoimmune disease. Lung fibrosis occurs in ∼80% of patients with SSc; 25% to 30% develop progressive interstitial lung disease (ILD). The pathogenesis of fibrosis in SSc-associated ILD (SSc-ILD) involves cellular injury, activation/differentiation of mesenchymal cells, and morphological/biological changes in epithelial/endothelial cells. Risk factors for progressive SSc-ILD include older age, male sex, degree of lung involvement on baseline high-resolution computed tomography imaging, reduced Dl_CO, and reduced FVC. SSc-ILD does not share the genetic risk architecture observed in idiopathic pulmonary fibrosis (IPF), with key risk factors yet to be identified. Presence of anti-Scl-70 antibodies and absence of anti-centromere antibodies indicate increased likelihood of progressive ILD. Elevated levels of serum Krebs von den Lungen-6 and C-reactive protein are both associated with SSc-ILD severity and predict SSc-ILD progression. A promising prognostic indicator is serum chemokine (C-C motif) ligand 18. SSc-ILD shares similarities with IPF, although clear differences exist. Histologically, a nonspecific interstitial pneumonia pattern is commonly observed in SSc-ILD, whereas IPF is defined by usual interstitial pneumonia. The course of SSc-ILD is variable, ranging from minor, stable disease to a progressive course, whereas all patients with IPF experience progression of disease. Although appropriately treated patients with SSc-ILD have better chances of stabilization and survival, a relentlessly progressive course, akin to IPF, is seen in a minority. Better understanding of cellular and molecular pathogenesis, genetic risk, and distinctive features of SSc-ILD and identification of robust prognostic biomarkers are needed for optimal disease management.

Connective Tissue Disease-Associated Interstitial Lung Disease: Evaluation and Management

Interstitial lung disease is common among patients with connective tissue disease and is an important contributor to morbidity and mortality. Infection and drug toxicity must always be excluded as the cause of radiographic findings. Immunosuppression remains a mainstay of therapy despite few controlled trials supporting its use. When a decision regarding therapy initiation is made, considerations include an assessment of disease severity as well as a determination of the rate of progression. Because patients may have extrathoracic disease activity, a multidisciplinary approach is crucial and should include supportive and nonpharmacologic management strategies.

Quantitative computed tomography assessment for systemic sclerosis-related interstitial lung disease: comparison of different methods

OBJECTIVES

To compare the previously defined six different histogram-based quantitative lung assessment (QLA) methods on high-resolution CT (HRCT) in patients with systemic sclerosis (SSc)-related interstitial lung disease (ILD).

METHODS

The HRCT images of SSc patients with ILD were reviewed, and the visual ILD score (semiquantitative) and the severity of ILD (limited or extensive) were calculated. The QLA score of ILD was evaluated using the previously defined six different methods and parameters (different lung attenuation ranges, skewness, kurtosis, mean lung attenuation, and standard deviation [SD]). Pulmonary function tests (PFTs) were also performed on all patients. Relationships among variables were evaluated using Spearman's correlation coefficient (r). Diagnostic performance of quantitative methods for the ability to differentiate the limited from extensive ILD was calculated using ROC analysis.

RESULTS

Fifty-five patients were included in the study. There was a significant correlation between all quantitative and semiquantitative measurement results (p < 0.0001). The QLA scores revealed a significant correlation with PFT results. The kurtosis value of the voxels between - 200 and - 1024 Hounsfield unit (HU) (Method-5) showed the best correlation with semiquantitative evaluation (r = - 0.740, p < 0.0001). The ROC analysis demonstrated the best performance of SD of the voxels between - 400 and - 950 HU (Method-6) for histogram analysis method and Method-3 (voxels between - 260 and - 600 HU were calculated as ILD) for CT density cutoff methods.

CONCLUSIONS

All the QLA methods are applicable in assessing the ILD score in SSc patients and have potential importance to differentiate limited from extensive ILD.

KEY POINTS

• Quantitative interstitial lung disease assessment helps clinicians to assess systemic sclerosis patients with interstitial lung disease. • Quantitative lung assessment methods are applicable in assessing the interstitial lung disease score in systemic sclerosis patients. • Quantitative lung assessment methods have potential importance in the management of patients.

Treatment of systemic sclerosis-associated interstitial lung disease: Lessons from clinical trials

Systemic sclerosis-associated interstitial lung disease remains a leading cause of mortality. Despite decades of clinical trials, the treatment effects of disease modifying anti-rheumatic drugs continue to be modest and there remains a great need for therapies that attenuate and hopefully ameliorate parenchymal lung disease. In this review, we highlight the key clinical trials that have shaped the management strategies employed by the authors, providing their strength of recommendation based on level of evidence. We also review lessons learned in more recent years, suggesting a benefit in targeting patients with subclinical interstitial lung disease with high risk for progression early in the disease course, as well as the benefit seen in a large clinical trial leading to the first Food and Drug Administration-approved treatment for systemic sclerosis-associated interstitial lung disease. These lessons come in a context of heterogeneity of patient populations and response to therapy, as well as the inherent constraints of time-limited studies to detect meaningful outcomes for patients.

Systemic sclerosis-associated interstitial lung disease

Systemic sclerosis is an autoimmune connective tissue disease, which is characterised by immune dysregulation and progressive fibrosis that typically affects the skin, with variable internal organ involvement. It is a rare condition that affects mostly young and middle-aged women, resulting in disproportionate morbidity and mortality. Currently, interstitial lung disease is the most common cause of death among patients with systemic sclerosis, with a prevalence of up to 30% and a 10-year mortality of up to 40%. Interstitial lung disease is more common among African Americans and in people with the diffuse cutaneous form of systemic sclerosis or anti-topoisomerase 1 antibodies. Systemic sclerosis-associated interstitial lung disease most commonly presents with dyspnoea, cough, and a non-specific interstitial pneumonia pattern on CT scan, with a minority of cases fulfilling the criteria for usual interstitial pneumonia. The standard therapy has traditionally been combinations of immunosuppressants, particularly mycophenolate mofetil or cyclophosphamide. These immunosuppressants can be supplemented by targeted biological and antifibrotic therapies, whereas autologous haematopoietic stem-cell transplantation and lung transplantation are reserved for refractory cases.

The identification and management of interstitial lung disease in systemic sclerosis: evidence-based European consensus statements

BACKGROUND

Systemic sclerosis-associated interstitial lung disease (ILD) carries a high mortality risk; expert guidance is required to aid early recognition and treatment. We aimed to develop the first expert consensus and define an algorithm for the identification and management of the condition through application of well established methods.

METHODS

Evidence-based consensus statements for systemic sclerosis-associated ILD management were established for six domains (ie, risk factors, screening, diagnosis and severity assessment, treatment initiation and options, disease progression, and treatment escalation) using a modified Delphi process based on a systematic literature analysis. A panel of 27 Europe-based pulmonologists, rheumatologists, and internists with expertise in systemic sclerosis-associated ILD participated in three rounds of online surveys, a face-to-face discussion, and a WebEx meeting, followed by two supplemental Delphi rounds, to establish consensus and define a management algorithm. Consensus was considered achieved if at least 80% of panellists indicated agreement or disagreement.

FINDINGS

Between July 1, 2018, and Aug 27, 2019, consensus agreement was reached for 52 primary statements and six supplemental statements across six domains of management, and an algorithm was defined for clinical practice use. The agreed statements most important for clinical use included: all patients with systemic sclerosis should be screened for systemic sclerosis-associated ILD using high-resolution CT; high-resolution CT is the primary tool for diagnosing ILD in systemic sclerosis; pulmonary function tests support screening and diagnosis; systemic sclerosis-associated ILD severity should be measured with more than one indicator; it is appropriate to treat all severe cases; no pharmacological treatment is an option for some patients; follow-up assessments enable identification of disease progression; progression pace, alongside disease severity, drives decisions to escalate treatment.

INTERPRETATION

Through a robust modified Delphi process developed by a diverse panel of experts, the first evidence-based consensus statements were established on guidance for the identification and medical management of systemic sclerosis-associated ILD.

FUNDING

An unrestricted grant from Boehringer Ingelheim International.

Effects of N-acetylcysteine on Pulmonary Functions in Patients with Systemic Sclerosis: A Randomized Double Blind, Placebo Controlled Study

BACKGROUND

Systemic sclerosis (SSc) is a systematic and rare autoimmune disease that affects many organs. N-acetylcysteine (NAC), thiol-containing compound, can act both as the precursor of reduced glutathione and direct scavenger of reactive oxygen species.

OBJECTIVE

We assessed the clinical effect of NAC on the pulmonary function test of patients with diffuse scleroderma.

METHODS

This study is a randomized double-blind clinical trial that was done on 25 patients with diffuse SSc without lung involvement on primary chest high-resolution computed tomography. Placebo was administered for 13 patients and 1200 milligram NAC for 12 patients. Body plethysmography parameters were assessed at the beginning of the study and after 24 weeks.

RESULTS

Patients in the two groups were matched in the basic demographic data like age, duration of disease, and modified Rodnan skin score. The analysis showed no significant differences in parameters of plethysmography between the two groups. After importing the data of 2 patients in the placebo-treated group, who developed interstitial lung disease, DLCO in the placebo-treated group was 90.69 ± 21.29 milliliter at the end of the study, which significantly decreased compared with the beginning of the study (102.30 ± 13.83 ml). Also, changes of DLCO between the two groups were significantly different.

CONCLUSION

In this trial, the sensitivity of DLCO as the first marker in the evaluation of pulmonary function in patients with SSc was confirmed. On the other hand, NAC had no effect versus placebo in a period of 24 weeks.

Interstitial Lung Disease in Systemic Sclerosis: Focus on Early Detection and Intervention

Systemic sclerosis (SSc) is a progressive and often devastating disease characterized by autoimmune dysfunction, vasculopathy, and fibrosis. Interstitial lung disease (ILD) is identified in the majority of patients with SSc and is the leading cause of SSc-related mortality. Although clinical manifestations and ILD severity vary among patients, lung function typically declines to the greatest extent during the first 3-4 years after disease onset. We aim to provide an overview of SSc-associated ILD (SSc-ILD) with a focus on current and emerging tools for early diagnosis of ILD and current and novel treatments under investigation. Early detection of ILD provides the opportunity for early therapeutic intervention, which could improve patient outcomes. Thoracic high-resolution computed tomography is the most effective method of identifying ILD in patients with SSc; it enables detection of mild lung abnormalities and plays an important role in monitoring disease progression. Cyclophosphamide and mycophenolate mofetil are the most commonly prescribed treatments for SSc-ILD. Recently, nintedanib (an antifibrotic) was approved by the Food and Drug Administration for patients with SSc-ILD; it is indicated for slowing the rate of decline in pulmonary function. However, there is a need for additional effective and well-tolerated disease-modifying therapy. Ongoing studies are evaluating other antifibrotics and novel agents. We envision that early detection of lung involvement, combined with the emergence and integration of novel therapies, will lead to improved outcomes in patients with SSc-ILD.

Natural History of Systemic Sclerosis-Related Interstitial Lung Disease: How to Identify a Progressive Fibrosing Phenotype

The natural history of interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) is highly variable. Historical observational studies have demonstrated that the greatest decline in lung function in SSc occurs early in the course of the disease; however, not all patients experience a decline in lung function even in the absence of treatment. Furthermore, among patients who do experience a decline in lung function, the rate of decline can be either rapid or slow. The most common clinical phenotypes of SSc-ILD therefore: (i) Rapid Progressors, (ii) Gradual Progressors, (iii) Stabilizers and (iv) Improvers. This review summarizes the features of SSc-ILD patients who are more likely to experience rapid progression of ILD, as well as those who are more likely not to experience ILD progression. Understanding the clinical, biological and radiographic factors that consistently predict ILD-related outcomes in SSc is central to our ability to recognize those patients who are at heightened risk for ILD progression. With new options available for treating patients with SSc-ILD, it is more important than ever to accurately identify patients who may derive the most benefit from aggressive SSc-ILD therapy. Early therapeutic intervention in patients with this progressive fibrosing phenotype may ultimately improve morbidity and mortality outcomes in patients with SSc-ILD.

Does Systemic Sclerosis-associated Interstitial Lung Disease Burn Out? Specific Phenotypes of Disease Progression

RATIONALE

Previous studies have suggested that interstitial lung disease (ILD) progresses most rapidly early in the course of systemic sclerosis-associated (SSc)-ILD, and that SSc-ILD is often more stable or even "burned out" after the first 4 years following diagnosis.

OBJECTIVES

Our objectives were to determine whether an apparent plateau in pulmonary function decline is due to survival bias and to identify distinct prognostic phenotypes of ILD progression.

METHODS

Consecutive patients with SSc-ILD from a single center were included. Pulmonary function measurements were typically performed every 6 months. Study participants were categorized into long-term survivors (>8 yr survival from diagnosis), and those with medium-term and short-term mortality (4-8 and <4 yr survival, respectively). We excluded those censored with less than 8 years of follow-up. Subject-specific slopes for change in forced vital capacity (FVC) and diffusing capacity of the lung for carbon monoxide (Dl_CO) were calculated using generalized linear models with mixed effects. The rate of decline in FVC was compared across prognostic groups.

RESULTS

The cohort included 171 study participants with SSc-ILD. A plateau in the progression of FVC was apparent in the full cohort analysis but disappeared with stratification into prognostic subgroups to account for survival bias. Those with short-term mortality had a higher annual rate of decline in FVC (-4.10 [95% confidence interval (CI), -7.92 to -0.28] vs. -2.14 [95% CI, -3.31 to -0.97] and -0.94 [-1.46 to -0.42]; P = 0.003) and Dl_CO (-5.28 [95% CI, -9.58 to -0.99] vs. -3.13 [95% CI, -4.35 to -1.92] and -1.32 [95% CI, -2.01 to -0.63]; P < 0.001) than those with medium-term mortality and long-term survival with adjustment for age, sex, and pack-years. Change in FVC in the previous year did not predict FVC change in the subsequent year.

CONCLUSIONS

Adults with SSc-ILD have distinct patterns of physiological progression that remain relatively consistent during long-term follow-up; however, recent change in FVC cannot be used to predict future change in FVC within shorter follow-up intervals. The findings of this study provide important information on the course of disease in SSc-ILD and identify specific phenotypes of progression that may improve clinical decision-making and design of future therapeutic trials.

Multiple External Root Resorption of Teeth as a New Manifestation of Systemic Sclerosis-A Cross-Sectional Study in Japan

BACKGROUND

Multiple external root resorption (MERR) has been reported in systemic sclerosis (SSc) patients in Japan and Spain. To establish whether MERR is a new manifestation, we investigated the prevalence of MERR and systemic and oral manifestations to be associated with MERR in patients with SSc.

METHODS

Root resorption was detected by dental X-rays, panoramagraphy or cone beam computed tomography (CBCT). The prevalence of systemic and oral manifestations was examined by rheumatologists and dentists, respectively. Autoantibodies were investigated using laboratory tests.

RESULTS

MERR was detected in four out of the 41 patients (9.8%) who participated in the present study. The prevalence of digital ulcers was significantly higher in patients with MERR (MERR vs non-MERR, 75% vs 16.2%, p < 0.05), whereas that of other systemic manifestations was not. The prevalence of face skin sclerosis (100% vs 10.8%, p < 0.01), calcinosis at the facial region (75% vs 0%, p < 0.01), limited mouth opening (75% vs 18.9% p < 0.05), temporomandibular disorder symptoms (50% vs 2.7%, p < 0.05), and tongue rigidity (75% vs 2.7%, p < 0.05) was significantly higher in patients with MERR.

CONCLUSION

SSc patients with MERR had highly homogenous maxillofacial manifestations. Further clinical and basic studies are needed to elucidate the mechanisms underlying MERR in SSc patients.

Management of systemic sclerosis-associated interstitial lung disease

PURPOSE OF REVIEW

To review the recently published data and provide a practical overview for management of systemic sclerosis-interstitial lung disease (SSc-ILD).

RECENT FINDINGS

Published evidence shows considerable practitioner variability in screening patients for ILD. Recent published data support use of cyclophosphamide or mycophenolate mofetil as first-line treatment of SSc-ILD. For patients not responding to first-line therapies, consideration is given to rituximab as rescue therapy. Recent trials of hematopoietic autologous stem cell transplantation have demonstrated benefit in patients with progressive SSc-ILD. Antifibrotic agents are approved in idiopathic pulmonary fibrosis; studies with antifibrotics are underway for SSc-ILD.

SUMMARY

The specter of rapidly progressive lung disease requires clinicians to risk stratify patients according to known predictors for progression and rigorously monitor for symptoms and advancing disease. The abovementioned therapies promise improved efficacy and favorable side-effect profiles compared to cyclophosphamide.

Determining progression of scleroderma-related interstitial lung disease

Interstitial lung disease occurs in the majority of patients with systemic sclerosis. Although interstitial lung disease is the number one cause of death in systemic sclerosis, interstitial lung disease progression rates vary considerably among patients with systemic sclerosis. Some patients with systemic sclerosis-associated interstitial lung disease have sub-clinical disease and may not derive benefit from immunosuppression, while others have a more aggressive interstitial lung disease phenotype. Reliable predictors of interstitial lung disease progression are lacking. The present review describes our current approach to monitoring systemic sclerosis-associated interstitial lung disease progression in clinical practice. To illustrate the marked heterogeneity that exists in interstitial lung disease progression rates in systemic sclerosis, this review presents the individual disease course of five unique patients with systemic sclerosis-associated interstitial lung disease who participated in the Scleroderma Lung Study II. These cases illustrate that treatment response rates vary in systemic sclerosis-associated interstitial lung disease and more research is needed to determine how to predict treatment response in systemic sclerosis-associated interstitial lung disease and to develop personalized treatment approaches for patients with this devastating disease.

Automated CT quantification methods for the assessment of interstitial lung disease in collagen vascular diseases: A systematic review

Interstitial lung disease (ILD) is highly prevalent in collagen vascular diseases and reduction of ILD is an important therapeutic target. To that end, reliable quantification of pulmonary disease severity is of great significance. This study systematically reviewed the literature on automated computed tomography (CT) quantification methods for assessing ILD in collagen vascular diseases. PRISMA-DTA guidelines for systematic reviews were used and 19 original research articles up to January 2018 were included based on a MEDLINE/Pubmed and Embase search. Quantitative CT methods were categorized as histogram assessment (12 studies) or pattern/texture recognition (7 studies). R² for correlation with visual ILD scoring ranged from 0.143 (p < 0.01) to 0.687 (p < 0.0001), for FVC from 0.048 (p < 0.0001) to 0.504 (p < 0.0001) and for DLCO from 0.015 (p = 0.61) to 0.449 (p < 0.0001). Automated CT methods are independent of reader's expertise and are a promising tool in the quantification of ILD in collagen vascular disease patients.