Detection and Monitoring of Interstitial Lung Disease in Patients with Systemic Sclerosis

Exploring explainable AI features in the vocal biomarkers of lung disease

This review delves into the burgeoning field of explainable artificial intelligence (XAI) in the detection and analysis of lung diseases through vocal biomarkers. Lung diseases, often elusive in their early stages, pose a significant public health challenge. Recent advancements in AI have ushered in innovative methods for early detection, yet the black-box nature of many AI models limits their clinical applicability. XAI emerges as a pivotal tool, enhancing transparency and interpretability in AI-driven diagnostics. This review synthesizes current research on the application of XAI in analyzing vocal biomarkers for lung diseases, highlighting how these techniques elucidate the connections between specific vocal features and lung pathology. We critically examine the methodologies employed, the types of lung diseases studied, and the performance of various XAI models. The potential for XAI to aid in early detection, monitor disease progression, and personalize treatment strategies in pulmonary medicine is emphasized. Furthermore, this review identifies current challenges, including data heterogeneity and model generalizability, and proposes future directions for research. By offering a comprehensive analysis of explainable AI features in the context of lung disease detection, this review aims to bridge the gap between advanced computational approaches and clinical practice, paving the way for more transparent, reliable, and effective diagnostic tools.

Low-Carbon Monoxide Diffusing Capacity, Patient-Reported Measures and Reduced Nailfold Capillary Density Are Associated with Interstitial Lung Disease in Systemic Sclerosis

The aim of this paper is to identify factors associated with interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) and build an algorithm to better define this association for a personalised application in clinical practice.

METHODS

A total of 78 SSc patients underwent HRCT to assess ILD. Demographic, clinical and laboratory variables were collected, focusing on those associated either directly or indirectly with lung involvement. The discriminant value of each variable was determined using the operating characteristic curves (ROC) and included in a model to estimate the strength of ILD association in SSc.

RESULTS

Thirty-three (42.31%) patients showed ILD on HRCT. DLco, M-Borg, GERD-Q and capillary density were significantly associated with the presence of ILD-SSc. A model including these variables had a coefficient of determination (R2) of 0.697. DLco had an AUC of 0.861 (p < 0.001) with a cut-off of ≤72.3% (sensitivity 78.8%, specificity 91.1%, +LR 8.86). The m-Borg Scale showed an AUC of 0.883 (p < 0.001) with a cut-off >2 (sensitivity 84.8%, specificity 82.2%, +LR 4.77), GERD-Q had an AUC of 0.815 (p < 0.001) with a cut-off >7 (sensitivity 72.7%, specificity 86.7%, +LR 5.45). The capillary density showed an AUC of 0.815 (p < 0.001) with a cut-off of ≤4.78 (sensitivity 87.9%, specificity 68.9%, +LR 2.82). Based on the pre-test probability values, these four variables were applied to Fagan's nomogram to calculate the post-test probability of this association.

CONCLUSIONS

Our study identified four associated clinical factors of ILD in SSc patients. Moreover, their inclusion in an algorithm for the post-test probability, tailored to the specific patients' characteristics, significantly increases the ability to find out the presence of SSc-ILD.

The Performance of Pulmonary Function Tests in Predicting Systemic Sclerosis-Interstitial Lung Disease in the European Scleroderma Trial and Research Database

BACKGROUND AND OBJECTIVES

In SSc, ILD is a major cause of morbidity and mortality. We aimed to investigate the performance of DLCO (diffusing capacity of lung carbon monoxide) and FVC (forced vital capacity) delta change (Δ) and baseline values in predicting the development of SSc-ILD.

METHODS

Longitudinal data of DLCO, FVC, and ILD on the HRCT of SSc patients from the EUSTAR database were evaluated at baseline (t0) and after 12 (±4) (t1) and 24 (±4) (t2) months.

RESULTS

474/17805 patients were eligible for the study (403 females); 46 (9.7%) developed ILD at t2. Positivity for anti-topoisomerase antibodies (117 patients) showed an association with ILD development at t2 (p = 0.0031). Neither the mean t0 to t1 change (Δ) of DLCO nor the mean t0 to t1 FVCΔ predicted the appearance of ILD at t2. Investigating the possible role of baseline DLCO and FVC values in predicting ILD appearance after 24 (±4) months, we observed a moderate predictive capability of t0 DLCO < 80%, stronger than that of FVC < 80%.

CONCLUSIONS

We suggest that an impaired baseline DLCO may be predictive of the appearance of ILD after 2 years of follow-up. This result advances the hypothesis that a reduction in gas exchange may be considered an early sign of lung involvement. However, further rigorous studies are warranted to understand the predictive role of DLCO evaluation in the course of SSc.

Radiologic approach and progressive exploration of connective tissue disease-related interstitial lung disease: meeting the curiosity of rheumatologists

Interstitial lung disease (ILD) is often observed in connective tissue diseases (CTDs), frequently in rheumatoid arthritis, systemic sclerosis, primary Sjögren's syndrome, and inflammatory myositis. Early detection of ILDs secondary to rheumatic diseases is important as timely initiation of proper management affects the prognosis. Among many imaging modalities, high-resuloution computed tomography (HRCT) serves the gold standard for finding early lung inflammatory and fibrotic changes as well as monitoring afterwards because of its superior spatial resolution. Additionally, lung ultrasound (LUS) and magnetic resonance imaging (MRI) are the rising free-radiation imaging tools that can get images of lungs of CTD-ILD. In this review article, we present the subtypes of ILD images found in each CTD acquired by HRCT as well as some images taken by LUS and MRI with comparative HRCT scans. It is expected that this discussion would be helpful in discussing recent advances in imaging modalities for CTD-ILD and raising critical points for diagnosis and tracing of the images from the perspective of rheumatologists.

Early detection of interstitial lung disease in rheumatic diseases: A joint statement from the Portuguese Pulmonology Society, the Portuguese Rheumatology Society, and the Portuguese Radiology and Nuclear Medicine Society

INTRODUCTION

Interstitial lung disease (ILD) contributes significantly to morbidity and mortality in connective tissue disease (CTD). Early detection and accurate diagnosis are essential for informing treatment decisions and prognosis in this setting. Clear guidance on CTD-ILD screening, however, is lacking.

OBJECTIVE

To establish recommendations for CTD-ILD screening based on the current evidence.

METHOD

Following an extensive literature research and evaluation of articles selected for their recency and relevance to the characterization, screening, and management of CTD-ILD, an expert panel formed by six pulmonologists from the Portuguese Society of Pulmonology, six rheumatologists from the Portuguese Society of Rheumatology, and six radiologists from the Portuguese Society of Radiology and Nuclear Medicine participated in a multidisciplinary discussion to produce a joint statement on screening recommendations for ILD in CTD.

RESULTS

The expert panel achieved consensus on when and how to screen for ILD in patients with systemic sclerosis, rheumatoid arthritis, mixed connective tissue disease, Sjögren syndrome, idiopathic inflammatory myopathies and systemic lupus erythematous.

CONCLUSIONS

Despite the lack of data on screening for CTD-ILD, an expert panel of pulmonologists, rheumatologists and radiologists agreed on a series of screening recommendations to support decision-making and enable early diagnosis of ILD to ultimately improve outcomes and prognosis in patients with CTD.

The Role of Lung Ultrasound in Systemic Sclerosis: A Systematic Review

BACKGROUND

In systemic sclerosis (SSc), high-resolution computed tomography (HRCT) of the chest is the standard criterion for the diagnosis of interstitial lung disease (ILD). However, recent evidence suggests that lung ultrasound (LUS) can also detect ILD, without radiation exposure. Thus, our goal was to perform a systematic review, aiming to clarify the role of LUS in the detection of ILD in SSc.

METHODS

A systematic review was carried out in PubMed and EMBASE (PROSPERO register number CRD42022293132), to identify studies that compared LUS with HRCT in the detection of ILD in patients with SSc. Risk of bias was assessed with the QUADAS-2 () tool.

RESULTS

Three hundred seventy-five publications were identified. After screening, 13 were included in the final analysis. No study presented high risk of bias. Lung ultrasound protocol was highly heterogeneous between authors, specifically concerning transducer, intercostal spaces evaluated, exclusion criteria, and definition of positive LUS. Most authors evaluated the presence of B-lines as a surrogate of ILD, with only 4 focusing on pleural changes. A positive correlation between LUS findings and ILD detected by HRCT was reported. Results also revealed high sensitivity (74.3%-100%) but variable specificity (16%-99%). Positive predictive value varied between 16% and 95.1%, and negative predictive value between 51.7% and 100%.

CONCLUSION

Lung ultrasound is sensitive in the detection of ILD, but specificity must be optimized. The value of pleural evaluation also requires further investigation. Moreover, a consensus is needed to define a uniform LUS protocol to implement in future investigations.

Juvenile and adult-onset scleroderma: different clinical phenotypes

OBJECTIVES

Systemic sclerosis (SSc) represents extremely rare disease with majority of data coming from adults. Studies comparing juvenile- (jSSc) and adult-onset (aSSc) patients are limited. We aimed to compare clinical features, treatment modalities and survival rates of jSSc and aSSc patients.

METHODS

A retrospective study among pediatric and adult Scl patients has been performed. Demographic characteristics, clinical features, autoantibody profiles, and treatment data were retrieved from the databases. Survival analysis was done using Kaplan-Meier plot and factors associated with mortality were identified with multiple regression analysis.

RESULTS

A total of 158 adults and 58 juvenile Scl patients were identified. The mean age at the disease onset was 37±14.7 vs. 8.8 ± 4.1 years, mean age at diagnosis 42±15.2 vs. 10.4 ± 3.8 years and mean follow-up duration was 6.3 ± 4.9 years vs. 6.6 ± 4.9 years for aSSc and jSSc patients, respectively. The frequency of interstitial lung disease (ILD) (50.9% vs 30%, p<0.001) and systemic hypertension (17.9% vs 0, p = 0.009) was significantly higher among aSSc. While aSSc patients had presented mostly with limited cutaneous subset (74.1%), diffuse cutaneous subset was the dominant subset among jSSc (76.7%), (p<0.001). The mortality rate was significantly higher among adults (p = 0.005). The ILD (p = 0.03) and cardiac insufficiency (p = 0.05) were independent risk factors of mortality in both aSSc and jSSc patients.

CONCLUSION

Juvenile and adult-onset Scl represent rarely seen conditions with different clinical phenotypes. Pediatric patients with LS are more commonly seen by pediatric rheumatologists, in contrary to adults. Diffuse disease subset is the dominant form among juvenile patients, whereas limited form is the main disease subset among adults. On the other hand, juvenile-onset patients have a better survival than those with adult-onset.

Epidemiology and Treatment of Systemic Sclerosis in Korea

Systemic sclerosis (SSc), a rare, chronic progressive systemic autoimmune disease of unknown etiology, is characterized by autoimmunity, tissue fibrosis, and obliterative vasculopathy. SSc can affect all major organs including the skin, blood vessels, lung, heart, kidneys, and gastrointestinal tract. Our understanding of its pathogenesis has increased over the past few decades, leading to improved diagnosis and treatment. However, the mortality rate of SSc remains considerable, mainly due to cardiopulmonary causes. A growing body of evidence suggests that geographical, regional, and ethnic differences could affect the epidemiology, clinical characteristics and prognosis of SSc. Although Korean data of this issue are lacking, a considerable amount of research has been published by many Korean researchers. To establish treatment strategies for Korean patients, extensive Korean research data are needed. This review summarizes the prevalence, incidence, mortality, and clinical and laboratory manifestations of Korean patients with SSc and discusses the current trends in evidence-based treatment and recommendations.

Predicting the Progression of Very Early Systemic Sclerosis: Current Insights

Systemic sclerosis (SSc) is a complex autoimmune connective tissue disease with distinct pathological hallmarks (ie, inflammation, vasculopathy, fibrosis) that may predominate at different stages in the disease course with varying severity. Initial efforts to classify patients with SSc identified a subset of patients with very early SSc. These patients possessed signs of SSc (eg, Raynaud phenomenon, SSc specific autoantibodies and/or nailfold capillary abnormalities) without fulfilling complete SSc classification criteria. Recognizing the inherent value in early diagnosis and intervention in SSc, researchers have endeavored to identify risk factors for progression from very early SSc to definite SSc. The present review summarizes the clinical phenotype of patients with very early and early SSc. Through a scoping review of recent literature, this review also describes risk factors for progression to definite SSc with a focus on the specific clinical features that arise early in the SSc disease course (eg, diffuse cutaneous sclerosis, interstitial lung disease, esophageal dysfunction, renal crisis, cardiac involvement). In addition to clinical risk factors, this review provides evidence for how biological data (ie, serological, genomic, proteomic profiles, skin bioengineering methods) can be integrated into risk assessment models in the future. Furthering our understanding of biological features of very early SSc will undoubtedly provide novel insights into SSc pathogenesis and may illuminate new therapeutic targets to prevent progression of SSc.

Advances in the Treatment of Systemic Sclerosis

Although systemic sclerosis (SSc) is currently incurable, there have been recent advances in treatment. This review article begins by providing a brief background to SSc in terms of disease subtyping and autoantibodies, because both predict disease trajectory and help clinicians to select appropriate monitoring and treatment protocols. Broad principles of management are then described: ‘disease-modifying’ therapies and therapies directed at reducing disease burden and/or progression of SSc-related digital vascular disease and of internal organ involvement. Next, advances in the management of digital vasculopathy, pulmonary arterial hypertension (PAH), interstitial lung disease (ILD) and early diffuse cutaneous SSc are discussed in turn, for example: (a) increased use of phosphodiesterase inhibitors and endothelin receptor antagonists for digital vasculopathy; (b) early recognition and treatment of PAH, including with combination therapies; (c) increased use of mycophenolate mofetil and of nintedanib in ILD; and (d) immunosuppression now as standard practice in early diffuse cutaneous SSc, and autologous haematopoietic stem cell transplantation for highly selected patients with progressive diffuse disease. Finally, future challenges are discussed, including ensuring that all patients with SSc are monitored and treated according to best practice guidelines, and whenever possible giving patients the opportunity to participate in clinical trials.