Clinical advances in the diagnosis and therapy of the interstitial lung diseases

The impact of pre-existing interstitial lung disease on radiation and checkpoint inhibitor pneumonitis in lung cancer patients: a systematic review and meta-analysis

Background

Current research presents conflicting evidence on whether pre-existing interstitial lung disease (ILD) serves as a risk factor for radiation pneumonitis (RP) and checkpoint inhibitor pneumonitis (CIP) in patients with lung cancer.

Objectives

This study aims to systematically evaluate the impact of pre-existing ILD on the risk of developing RP and CIP in lung cancer patients.

Design

A systematic review and meta-analysis was conducted using a random-effects model.

Data sources and methods

PubMed, Embase, and Web of Science were searched to identify relevant studies. A random-effects model was applied to estimate the risk and incidence of RP and CIP in lung cancer patients with pre-existing ILD compared to those without ILD. Sensitivity analyses were performed to assess the robustness of the pooled findings, and potential publication bias was evaluated using Begg's and Egger's tests.

Results

A total of 12 studies involving 2576 patients were included in the RP risk assessment, while 29 studies with 8037 patients were analyzed for CIP risk. The pooled results indicated that pre-existing ILD significantly increased the risk of developing any-grade RP (odds ratio (OR): 3.63, 95% confidence interval (CI): 2.26-5.83) and severe RP (OR: 6.10, 95% CI: 2.68-13.86) in lung cancer patients. Subgroup analyses identified stereotactic body radiation therapy as the modality associated with the lowest risk of any-grade RP in these patients. Similarly, pre-existing ILD was associated with a significantly higher risk of any-grade CIP (OR: 3.86, 95% CI: 2.65-5.61) and severe CIP (OR: 3.24, 95% CI: 2.07-5.07), with anti-programmed cell death 1 therapies showing the highest CIP risk.

Conclusion

Pre-existing ILD markedly increases the risk of both RP and CIP in lung cancer patients. These findings underscore the critical importance of thorough ILD evaluation and the development of personalized treatment strategies to mitigate these risks prior to initiating cancer therapy.

Body composition, maximal fitness, and submaximal exercise function in people with interstitial lung disease

BACKGROUND

Cardiopulmonary exercise testing (CPET) is feasible, valid, reliable, and clinically useful in interstitial lung disease (ILD). However, maximal CPET values are often presented relative to body mass, whereas fat-free mass (FFM) may better reflect metabolically active muscle during exercise. Moreover, despite the value of maximal parameters, people with ILD do not always exercise maximally and therefore clinically relevant submaximal parameters must be identified. Therefore, this study assessed peak oxygen uptake (VO2peak) relative to FFM, identifying the validity of common scaling techniques; as well as characterising the oxygen uptake efficiency slope (OUES) and plateau (OUEP) as possible submaximal parameters.

METHODS

Participants with ILD underwent assessment of body composition and CPET via cycle ergometry during a single study visit. To determined effectiveness of scaling for body size, both body mass and FFM were scaled using ratio-standard (X/Y) and allometric (X/Yb) techniques. Pearsons's correlations determined agreement between OUES, OUEP, and parameters of lung function. Cohens kappa (κ) assessed agreement between OUES, OUEP and VO2peak.

RESULTS

A total of 24 participants (7 female; 69.8 ± 7.5 years; 17 with idiopathic pulmonary fibrosis) with ILD completed the study. Maximal exercise parameters did not require allometric scaling, and when scaled to FFM, it was shown that women have a significantly higher VO2peak than men (p = 0.044). Results also indicated that OUEP was significantly and positively correlated with DLCO (r = 0.719, p < 0.001), and held moderate agreement with VO2peak (κ = 0.50, p < 0.01).

CONCLUSION

This study identified that ratio-standard scaling is sufficient in removing residual effects of body size from VO2peak, and that VO2peak is higher in women when FFM is considered. Encouragingly, this study also identified OUEP as a possible alternative submaximal marker in people with ILD, and thus warrants further examination.

Evaluation of the protective effect of Compound Kushen Injection against radiation‑induced lung injury in mice

Radiation‑induced lung injury (RILI) is a prevalent complication following thoracic radiation, and currently there is a lack of effective intervention options. The present study investigated the potential of Compound Kushen Injection (CKI), a botanical drug, to mitigate inflammatory responses in mice with RILI, along with its underlying mechanisms of action. C3H mice underwent total lung irradiation (TLI) and intraperitoneal injection of CKI (2, 4 or 8 ml/kg) once daily for 8 weeks. Pre‑radiation treatment with 4 or 8 ml/kg CKI starting 2 weeks before TLI or concurrent treatment of 8 ml/kg CKI with TLI led to a significantly longer overall survival compared with the TLI vehicle‑treated group. Micro‑computed tomography evaluations showed that concurrent treatment with 8 ml/kg CKI was associated with a significantly lower incidence of RILI. Histological evaluations revealed that concurrent CKI (4 and 8 ml/kg) treatment significantly reduced grades of lung inflammation. Following radiation at 72 h, TLI plus vehicle‑treated mice had significantly elevated serum IL6, IL17A, and transforming growth factor β (TGF‑β) levels compared with non‑irradiated normal mice. Conversely, mice that received TLI plus CKI displayed lower cytokine levels than those in the TLI plus vehicle‑treated mice. Immunohistochemistry staining showed a reduction of TGF‑β positive cells in the lung tissues of TLI mice after CKI treatment. The concurrent TLI CKI‑treated mice had a significantly reduced cyclooxygenase 2 (COX‑2) activity and COX‑2 metabolites compared with TLI vehicle‑treated mice. These data highlight that CKI substantially reduced radiation‑induced lung inflammation, mitigated RILI incidence, and prolonged overall survival.

Radiomics Biomarkers to Predict Checkpoint Inhibitor Pneumonitis in Non-small Cell Lung Cancer

RATIONALE AND OBJECTIVES

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of non-small cell lung cancer (NSCLC). However, immune-related adverse events still occur, of which checkpoint inhibitor pneumonitis (CIP) is the most common. We aimed to construct and validate a contrast-enhanced computed tomography-based radiomic nomogram to predict the probability of CIP before ICIs treatment in NSCLC.

MATERIALS AND METHODS

We retrospectively analyzed 685 patients with NSCLC who were initially treated with ICIs. A total of 186 patients were included in our study, and an additional 52 patients from another hospital were considered for external validation. After radiomics feature extraction and selection, we applied a support vector machine classification model to distinguish CIP and used the probability as a radiomics signature. A radiomics-clinical logistic regression model was built using the filtered clinical parameters and a radiomic signature. Receiver operating characteristic, area under the curve (AUC), calibration curve, and decision curve analysis was used for inter-model comparison.

RESULTS

The combined radiomics-clinical model constructed using age, interstitial lung disease, emphysema at baseline, and radiomics signature showed an AUC of 0.935, 0.905, and 0.923 for the training, validation, and external validation cohorts, respectively. Compared with the clinical-only (AUC of 0.829, 0.826, and 0.809) and radiomics-only models (0.865, 0.847, and 0.841), the radiomics-clinical displayed better predictive power.

CONCLUSION

This combined radiomics-clinical model predicted the probability of CIP during ICIs treatment in patients with NSCLC with favorable accuracy and could therefore be used as an effective tool to guide clinical ICIs decisions.

Targeting pleuro-alveolar junctions reverses lung fibrosis in mice

Lung fibrosis development utilizes alveolar macrophages, with mechanisms that are incompletely understood. Here, we fate map connective tissue during mouse lung fibrosis and observe disassembly and transfer of connective tissue macromolecules from pleuro-alveolar junctions (PAJs) into deep lung tissue, to activate fibroblasts and fibrosis. Disassembly and transfer of PAJ macromolecules into deep lung tissue occurs by alveolar macrophages, activating cysteine-type proteolysis on pleural mesothelium. The PAJ niche and the disassembly cascade is active in patient lung biopsies, persists in chronic fibrosis models, and wanes down in acute fibrosis models. Pleural-specific viral therapeutic carrying the cysteine protease inhibitor Cystatin A shuts down PAJ disassembly, reverses fibrosis and regenerates chronic fibrotic lungs. Targeting PAJ disassembly by targeting the pleura may provide a unique therapeutic avenue to treat lung fibrotic diseases.

Influence of home-based pulmonary rehabilitation program among people with interstitial lung disease: A pre-post study

INTRODUCTION

Access to interstitial lung disease programs may not be available in rural settings. Home-based pulmonary rehabilitation (PR) programs have been proposed as an alternative to hospital-based programs.

METHOD

Forty participants with ILD underwent a structured unsupervised home-based pulmonary rehabilitation program from September 2020 to September 2022. Quality of life was assessed using St. George Respiratory Questionnaire (SGRQ) and functional capacity using 6-minute walk test (6MWT). The outcome measures were assessed at baseline and 4 weeks post-unsupervised home-based PR program.

RESULT

We recruited 40 participants with ILD. There was statistically significant improvement in the 6-minute walk distance (353.8 m and 368 m, effect size - 0.5, p ≤ .001) and quality of life using SGRQ total score (38.6 and 42.35, effect size - 2.5, p ≤ .001) between before and after receiving home-based PR among all 40 participants with ILD.

CONCLUSION

Four weeks of home-based PR program, using minimal resources, deliver short-term improvements in functional exercise capacity and quality of life among ILD participants. Our home-based PR program resulted in a quarter percentage improvement in functional capacity, and we believe that if consistency is maintained, it will result in similar changes corresponding to the already established Minimal Clinically Important Difference (MCID) of 35 m.

Diagnostic Value of Serum KL-6 in Interstitial Lung Diseases

Objective

To explore serum KL-6 level and investigate its diagnostic value in interstitial lung diseases (ILDs).

Methods

Serum KL-6 level was measured using the chemiluminescent enzyme immunoassay. Statistical analysis was performed for determining the KL-6 concentration of each group.

Results

KL-6 level (U/mL) in the ILD group was 1388.321 ±1943.116, which was higher than that in the control group, showing a significant statistical difference. ROC curve analysis based on the receiver operating characteristic curve showed the optimal cut-off value of 402.5U/mL, sensitivity of 77.4%, specificity of 93.4%, and accuracy of 89.4%; through Chi-square test with the two groups, the positive rate of KL-6 in patients with ILD was proved to be significantly higher than that in the control group. KL-6 level was 1063.00±504.757 in the idiopathic pulmonary fibrosis (IPF) group, 1346.892 ±1827.252 in the connective tissue disease-associated interstitial lung disease (CTD-ILD) group, 467.889±288.859 in the organizing pneumonia (OP) group, 8252.333±6050.625 in the pulmonary alveolar proteinosis (PAP) group, and 359.200±392.707 in the sarcoidosis group. The rank sum test showed that the differences were statistically significant. KL-6 level was the lowest in the sarcoidosis group, followed by that in the OP group.

Conclusion

Serum KL-6 level was confirmed to be highly sensitive, specific, and accurate in the diagnosis of ILD. Subgroup analysis showed that the KL-6 level was the lowest in the sarcoidosis group, followed by that in the OP group.

Cancer Therapy and Exercise Intolerance: The Heart Is But a Part: JACC: CardioOncology State-of-the-Art Review

The landscape of cancer therapeutics is continually evolving, with successes in improved survivorship and reduced disease progression for many patients with cancer. Improved cancer outcomes expose competing comorbidities, some of which may be exacerbated by cancer therapies. The leading cause of disability and death for many early-stage cancers is cardiovascular disease (CVD), which is often attributed to direct or indirect cardiac injury from cancer therapy. In this review, the authors propose that toxicities related to conventional and novel cancer therapeutics should be considered beyond the heart. The authors provide a framework using the oxygen pathway to understand the impact of cancer treatment on peak oxygen uptake, a marker of integrative cardiopulmonary function and CVD risk. Peripheral toxicities and the impact on oxygen transport are discussed. Consideration for the broad effects of cancer therapies will improve the prediction and identification of cancer survivors at risk for CVD, functional disability, and premature mortality and those who would benefit from therapeutic intervention, ultimately improving patient outcomes.

Challenges in Managing Newly Diagnosed Granulomatosis With Polyangiitis and Concurrent Respiratory Infections: A Retrospective Case Series

INTRODUCTION

Granulomatosis with polyangiitis (GPA), formerly termed Wegener's granulomatosis, is an autoimmune disease marked by necrotizing granulomatous inflammation and vasculitis affecting small-sized vessels. It commonly impacts the renal and respiratory systems.

MATERIALS AND METHODS

This retrospective case series sampling conducted in a tertiary care hospital between May 2023 and April 2024 examined six newly diagnosed GPA patients who were proteinase 3 cytoplasmic-antinuclear cytoplasmic antibody (PR3 c-ANCA) positive and had concurrent respiratory infections. None of them had any prior immunosuppressive conditions. The age range was 18-47 years with a mean of 35.0 (standard deviation: 11.83). All the patients had pneumonia (N=6, 100%). Out of all, five had bacterial pneumonia (N=5, 83.3%) and one had tuberculous pneumonia (N=1, 16.7%). A high level of PR3 c-ANCA (>150 RU/mL) was noted in four patients (N=4, 66.7%). Common symptoms included dry cough (N=5, 83.3%), loss of weight and appetite (N=2, 33.3%), and fever (N=2, 33.3%). Three patients had otitis media and/or nasal polyposis (N=3, 50%). Two patients (N=2, 33.3%) with life-threatening organ dysfunction were given concurrent antibiotics and steroids; the antibiotics were later modified based on culture and sensitivity results. One of these patients received antituberculosis therapy as Mycobacterium tuberculosis (MTB) was detected after 27 days of incubation in mycobacterial growth indicator tube broth. The remaining four patients (N=4, 66.7%) received antibiotics initially for 5-7 days until clinical resolution of pneumonia. Ultimately, they all showed clinical and radiological resolution (N=6, 100%) within 3-6 months of treatment.

RESULTS

The patients exhibited constitutional symptoms such as fever and weight loss; lower airway disease symptoms including dry cough and hemoptysis; nasal and ear disease symptoms like epistaxis, ear pain, and ear discharge; and a renal disease symptom, hematuria. Computed tomography of the thorax revealed bilateral consolidations, most of which were cavitating. Bronchoalveolar lavage cultures grew Escherichia coli, Burkholderia cepacia, Pseudomonas aeruginosa, Klebsiella pneumoniae, and MTB, whereas pus swab cultures from otitis media grew Pseudomonas aeruginosa, Staphylococcus aureus, and coagulase-negative staphylococci.

DISCUSSION

This study highlights the therapeutic challenges of GPA complicated by concurrent infections. Patients exhibited typical GPA signs, confirmed by PR3 c-ANCA levels. Concurrent infections require cautious antibiotic treatment before starting immunosuppressive therapy, except in life-threatening organ dysfunction. A unique case presented with both tuberculosis and GPA. Tailored treatment regimens combining antibiotics and immunosuppressives, including corticosteroids, methotrexate, and rituximab, resulted in clinical and radiological improvement in all the patients within 3-6 months. The addition of co-trimoxazole reduced the incidence of non-severe GPA relapses.

CONCLUSION

Tailored treatment plans addressing both infectious and autoimmune aspects are essential for optimal care in GPA complicated by concurrent infections. This study highlights the need for a multidisciplinary approach involving pulmonologist, rheumatologist, microbiologist, and pathologist in the diagnosis and treatment of GPA, emphasizing the importance of individualized treatment plans tailored to the specific clinical scenario.

Assessing Lung Fibrosis with ML-Assisted Minimally Invasive OCT Imaging

This paper presents a combined optical coherence tomography (OCT) imaging/machine learning (ML) technique for real-time analysis of lung tissue morphology to determine the presence and level of invasiveness of idiopathic lung fibrosis (ILF). This is an important clinical problem as misdiagnosis is common, resulting in patient exposure to costly and invasive procedures and substantial use of healthcare resources. Therefore, biopsy is needed to confirm or rule out radiological findings. Videoscopic-assisted thoracoscopic wedge biopsy (VATS) under general anesthesia is typically necessary to obtain enough tissue to make an accurate diagnosis. This kind of biopsy involves the placement of several tubes through the chest wall, one of which is used to cut off a piece of lung to send for evaluation. The removed tissue is examined histopathologically by microscopy to confirm the presence and the pattern of fibrosis. However, VATS pulmonary biopsy can have multiple side effects, including inflammation, tissue morbidity, and severe bleeding, which further degrade the quality of life for the patient. Furthermore, the results are not immediately available, requiring tissue processing and analysis. Here, we report an initial attempt of using ML-assisted polarization sensitive OCT (PS-OCT) imaging for lung fibrosis assessment. This approach has been preliminarily tested on a rat model of lung fibrosis. Our preliminary results show that ML-assisted PS-OCT imaging can detect the presence of ILF with an average of 77% accuracy and 89% specificity.

Predictive factors for severe radiation-induced lung injury in patients with lung cancer and coexisting interstitial lung disease

BACKGROUND AND PURPOSE

This study aimed to investigate the predictive factors of severe radiation-induced lung injury (RILI) in patients with lung cancer and coexisting interstitial lung disease (ILD) undergoing conventionally fractionated thoracic radiotherapy.

MATERIALS AND METHODS

The study includes consecutive patients treated with thoracic radiotherapy for lung cancer at two tertiary centers between 2010 and 2021. RILI severity was graded using the National Cancer Institute Common Terminology Criteria version 5.0, with severe RILI defined as toxicity grade ≥4, and symptomatic RILI as grade ≥2. The absolute neutrophil count (ANC), absolute lymphocyte count (ALC), and C-reactive protein were collected within 4 weeks before starting radiotherapy. Neutrophil-lymphocyte ratios (NLR) were calculated as ANC/ALC. The median follow-up was 9 (range, 6-114) months.

RESULTS

Among 54 patients, 22 (40.7 %) had severe RILI. On multivariate logistic regression analysis, high pretreatment ANC (p = 0.030, OR = 4.313), pretreatment NLR (p = 0.007, OR = 5.784), and ILD severity (p = 0.027, OR = 2.416) were significant predictors of severe RILI. Dosimetric factors were not associated with severe RP. Overall survival was significantly worse for patients with severe RILI than those without, with 1-year cumulative overall survival rates of 7.4 % and 62.8 %, respectively.

CONCLUSION

Pretreatment blood NLR, ANC, and ILD severity were associated with severe RILI. Overall survival was dismal for patients with severe RILI.

Fleischner Society: Glossary of Terms for Thoracic Imaging

Members of the Fleischner Society have compiled a glossary of terms for thoracic imaging that replaces previous glossaries published in 1984, 1996, and 2008, respectively. The impetus to update the previous version arose from multiple considerations. These include an awareness that new terms and concepts have emerged, others have become obsolete, and the usage of some terms has either changed or become inconsistent to a degree that warranted a new definition. This latest glossary is focused on terms of clinical importance and on those whose meaning may be perceived as vague or ambiguous. As with previous versions, the aim of the present glossary is to establish standardization of terminology for thoracic radiology and, thereby, to facilitate communications between radiologists and clinicians. Moreover, the present glossary aims to contribute to a more stringent use of terminology, increasingly required for structured reporting and accurate searches in large databases. Compared with the previous version, the number of images (chest radiography and CT) in the current version has substantially increased. The authors hope that this will enhance its educational and practical value. All definitions and images are hyperlinked throughout the text. Click on each figure callout to view corresponding image. © RSNA, 2024 Supplemental material is available for this article. See also the editorials by Bhalla and Powell in this issue.

Evaluation of the Protective Effect of Compound Kushen Injection Against Radiation- induced Pneumonitis in Mice

Background Radiation-induced lung injury (RILI) via inflammation is a common adverse effect of thoracic radiation that negatively impacts patient quality of life and survival. Compound kushen injection (CKI), a botanical drug treatment, was examined for its ability to reduce RILI, and inflammatory responses and improve survival in mice exposed total lung irradiation (TLI). CKI's specific mechanisms of action were also evaluated. Methods C3H mice underwent TLI and were treated with CKI (2, 4, or 8 mL/kg) intraperitoneally once a day for 8 weeks. The effects of CKI on survival were estimated by Kaplan-Meier survival analysis and compared by log-rank test. RILI damage was evaluated by histopathology and micro-computed tomography (CT). Inflammatory cytokines and cyclooxygenase metabolites were examined by IHC staining, western blot, and ELISA. Results Pre-irradiation treatment with 4 or 8 mL/kg CKI starting 2 weeks before TLI or concurrent treatment with 8 mL/kg CKI were associated with a significantly longer survival compared with TLI vehicle-treated group ( P  < 0.05). Micro-CT images evaluations showed that concurrent treatment with 8 mL/kg CKI was associated with significantly lower incidence of RILI ( P  < 0.05). Histological evaluations revealed that concurrent TLI treatment of CKI (4 and 8 mL/kg) significantly reduced lung inflammation (p < 0.05). Mechanistic investigation showed that at 72 hours after radiation, TLI plus vehicle mice had significantly elevated serum IL6, IL17A, and TGF-β levels compared with non-irradiated, age-matched normal mice; in contrast, levels of these cytokines in mice that received TLI plus CKI treatment were lower than those in the TLI plus vehicle-treated mice ( P  < 0.05) and similar to the nonirradiated mice. IHC staining showed that the CKI treatment led to a reduction of TGF-β positive cells in the lung tissues of TLI mice (P < 0.01). The concurrent CKI with TLI treatment group had a significant reduction in COX-2 activity and COX-2 metabolites compared with the TLI vehicle-treated group ( P  < 0.05). Conclusions These data suggest that CKI treatment was associated with reduced radiation-induced inflammation in lung tissues, reduced RILI, and improved survival. Further investigation of CKI in human clinical trials as a potential radioprotector against RILI to improve patients' quality of life and survival is warranted.

Cross-Cancer Type Evaluation of Potential Interstitial Lung Disease Complications of Immune Checkpoint Inhibitors Using JADER

Interstitial lung disease (ILD) is a serious adverse event caused by the administration of immune checkpoint inhibitors (ICIs). However, only few large-scale studies have explored the association among ICI use, underlying cancer type, and ILD complications. This study aimed to analyze the association between the primary cancer type and ICI-induced ILD in a cross-sectional manner using the Japanese Adverse Drug Event Report (JADER) database. Nivolumab and pembrolizumab (anti-programmed cell death 1 (PD-1) antibodies) and durvalumab, avelumab, and atezolizumab (anti-programmed cell death ligand 1 (PD-L1) antibodies) were included as ICIs in this study. Adverse events were identified based on the preferred terms of Medical Dictionary for Regulatory Activities (MedDRA) version 27.0/J listed in the Standardized MedDRA Queries (SMQ) "interstitial lung disease." The reporting odds ratio was calculated to detect the association between ICI use and ILD complications, and a signal was detected if the lower limit of the 95% confidence interval exceeded 1. In the analysis of all cancer types, a signal was detected for all ICIs except avelumab. An association between ICI and ILD was detected for all cancer types with nivolumab. However, pembrolizumab exhibited a signal only in colorectal cancer. In contrast, anti-PD-L1 antibodies displayed signals in five cancer types, excluding head and neck cancer, which was not reported in JADER. Among these cancer types, atezolizumab exhibited a signal only in breast cancer. The results of this study will help guide the safe use of ICIs based on the underlying cancer type in terms of ILD complications.

Beyond the Lungs: O 2 Supplementation Improves Cerebral Oxygenation and Fatigue during Exercise in Interstitial Lung Disease

PURPOSE

Cerebral hypoxia may exacerbate the perception of fatigue. We previously demonstrated that exercise-related hypoxemia, a hallmark of fibrotic interstitial lung disease ( f -ILD), dose dependently impairs cerebral oxygenation in these patients. It is unknown whether normalizing cerebral oxygenation with O 2 supplementation would be associated with positive changes in a relevant patient-centered outcome during exercise in f -ILD, such as improved perceived fatigue.

METHODS

Fourteen patients (12 males, 72 ± 8 yr, 8 with idiopathic pulmonary fibrosis, lung diffusing capacity for carbon monoxide = 44% ± 13% predicted) performed a constant-load (60% peak work rate) cycle test to symptom limitation (Tlim) breathing medical air. Fourteen controls cycled up to Tlim of an age- and sex-matched patient. Patients repeated the test on supplemental O 2 (fraction of inspired O 2 = 0.41 ± 0.08) for the same duration. Near-infrared spectroscopy and the rating-of-fatigue (ROF) scale assessed prefrontal cortex oxygenation and perceived fatigue, respectively.

RESULTS

Patients showed severe exertional hypoxemia (Tlim O 2 saturation by pulse oximetry = 80% ± 8%); they had poorer cerebral oxygenation (e.g., oxy-deoxyhemoglobin difference [HbDiff] = -3.5 ± 4.7 [range = -17.6 to +1.9] vs +1.9 ± 1.7 μmol from rest) and greater fatigue (ROF = 6.2 ± 2.0 vs 2.6 ± 2.3) versus controls under air ( P < 0.001). Reversal of exertional hypoxemia with supplemental O 2 led to improved HbDiff (+1.7 ± 2.4 μmol from rest; no longer differing from controls) and lower ROF scores (3.7 ± 1.2, P < 0.001 vs air) in patients. There was a significant correlation between O 2 -induced changes in HbDiff and ROF scores throughout exercise in f -ILD ( rrepeated-measures correlation = -0.51, P < 0.001).

CONCLUSIONS

Supplemental O 2 improved cerebral oxygenation during exercise in f -ILD, which was moderately associated with lower ratings of perceived fatigue. Reversing cerebral hypoxia with O 2 supplementation may thus have positive effects on patients' disablement beyond those expected from lower ventilation and dyspnea in this patient population.

May noninvasive mechanical ventilation and/ or continuous positive airway pressure increase the bronchoalveolar lavage salvage in patients with pulmonary diseases? Randomized clinical trial - Study protocol

PURPOSE

Bronchoalveolar lavage (BAL) procedure is a useful tool in the diagnosis of patients with interstitial lung disease (ILD) and is helpful in clinical research of chronic obstructive pulmonary disease (COPD) patients. Still little is known about predictors of poor BAL salvage. The trial aims to find the most efficient way to improve BAL recovery.

MATERIAL AND METHODS

Our study is a prospective, multicenter, international, two-arm randomized controlled trial. We aim to obtain BAL samples from a total number of 300 patients: 150 with ILD and 150 with COPD to achieve a statistical power of 80 ​%. Patients with initial BAL salvage <60 ​% will be randomized into the non-invasive ventilation (NIV) or continuous positive airway pressure (CPAP) arm. The NIV and CPAP will be set according to the study protocol. The influence on BAL salvage will be assessed in terms of BAL volume and content. Multivariable analysis of the additional test results to determine predictors for low BAL recovery will be conducted. In a study subgroup of approximately 20 patients per specific disease, a metabolomic assessment of exhaled air condensate will be performed. All procedures will be assessed in terms of the patient's safety. The trial was registered on clinicaltrials.gov (ID# NCT05631132). Interested experienced centers are invited to join the research group by writing to the corresponding author.

CONCLUSION

The results of our prospective study will address the currently unsolved problem of how to increase BAL salvage in patients with pulmonary diseases without increasing the risk of respiratory failure exacerbation.

Increased expiratory flows identify early interstitial lung disease

BACKGROUND

Most interstitial lung diseases (ILDs) manifest with a restrictive ventilatory defect as the common physiologic abnormality. Low carbon monoxide diffusing capacity (Dlco) is considered to be the earliest abnormality on pulmonary function tests (PFTs) in patients with ILD. However, its measurement requires complex and expensive equipment. Our study aimed to assess if high expiratory flows are the earliest PFT abnormality in patients with idiopathic pulmonary fibrosis (IPF) and ILD.

METHODS

In a real-world cohort of incident cases with ILD, we identified the initial PFTs on all patients newly diagnosed with ILD at Kingston Health Sciences Center (in Kingston, Ontario, Canada) between 2013 and 2017. The diagnosis of ILD, including IPF, was established as per current guidelines. Among patients with normal forced vital capacity (FVC), total lung capacity (TLC), and Dlco, we assessed the frequency of high expiratory flows defined as forced expiratory volume in 1 s (FEV1)/FVC, FEF25, FEF25-75, FEF75, and peak expiratory flow > 95% confidence limit of normal. We adjusted for emphysema, increased airway resistance, and obesity.

RESULTS

We assessed PFTs of 289 patients with ILD; 88 (30%) of them had normal FVC, TLC, and Dlco. Among these, high FEV1/FVC was the most common abnormality in 37% of patients, in 43% of nonobese patients, and in 58% of those with no emphysema and normal airway resistance. Results were similar in the 88 patients with IPF.

CONCLUSIONS

High FEV1/FVC could allow identifying patients with ILD/IPF in the earliest stages of their disease with simple spirometry, leading to earlier diagnosis and treatment.

Serum Rcn3 level is a potential diagnostic biomarker for connective tissue disease-associated interstitial lung disease and reflects the severity of pulmonary function

BACKGROUND

Although reticulocalbin 3 (Rcn3) has a critical role in alveolar epithelial function as well as in pathogenesis of pulmonary fibrosis, no study has yet examined its diagnostic and prognostic values for interstitial lung disease (ILD). This study aimed to evaluate Rcn3 as a potential marker in differential diagnosis of idiopathic pulmonary fibrosis (IPF) and connective tissue disease-associated interstitial lung disease (CTD-ILD) and in reflecting the severity of disease.

METHODS

This was a retrospective observational pilot study included 71 ILD patients and 39 healthy controls. These patients were stratified into IPF group (39) and CTD-ILD group (32). The severity of ILD was evaluated through pulmonary function test.

RESULTS

Serum Rcn3 level was statistically higher in CTD-ILD patients than that in IPF patients (p = 0.017) and healthy controls (p = 0.010). Serum Rcn3 further showed statistically negative correlation with pulmonary function indexes (TLC% pred and DLCO% pred) and positive correlation with inflammatory indexes (CRP and ESR) (r =  - 0.367, p = 0.039; r =  - 0.370, p = 0.037; r = 0.355, p = 0.046; r = 0.392, p = 0.026, respectively) in CTD-ILD patients rather than IPF patients. ROC analysis demonstrated that serum Rcn3 had superior diagnostic value for CTD-ILD and a cutoff value of 2.73 ng/mL had a sensitivity of 69%, a specificity of 69% and an accuracy of 45% for diagnose of CTD-ILD.

CONCLUSIONS

Serum Rcn3 levels might be a clinically useful biomarker in screening and evaluating CTD-ILD.

Immune cell profiles and patient clustering in complex cases of interstitial lung disease

Interstitial lung disease comprises numerous clinical entities posing significant challenges towards a prompt and accurate diagnosis. Amongst the contributing factors are intricate pathophysiological mechanisms, an overlap between conditions, and interobserver disagreement. We developed a model for patient clustering offering an additional approach to such complex clinical cases. The model is based on surface phenotyping of over 40 markers on immune cells isolated from bronchoalveolar lavage in combination with clinical data. Based on the marker expression pattern we constructed an individual immune cell profile, then merged these to create a global profile encompassing various pathologies. The contribution of each participant to the global profile was assessed through dimensionality reduction tools and the ensuing similarity between samples was calculated. Our model enables two approaches. First, assessing the immune cell population landscape similarity between patients within a diagnostic group allows rapid identification of divergent profiles, which is particularly helpful for cases with uncertain diagnoses. Second, sample clustering is based exclusively on the calculated similarity of the immune cell profiles, thereby removing physician bias and relying on cellular nearest neighbors.

Quantifying leg muscle deoxygenation during incremental cycling in hypoxemic patients with fibrotic interstitial lung disease

BACKGROUND

Hypoxaemia and cardiocirculatory abnormalities may impair muscle oxygen (O₂ ) delivery relative to O₂ requirements thereby increasing the rate of O₂ extraction during incremental exercise in fibrotic interstitial lung disease (f-ILD). Using changes in deoxyhaemoglobin concentration ([HHb]) by near-infrared spectroscopy (NIRS) as a proxy of O₂ extraction, we investigated whether a simplified (double-linear) approach, previously tested in heart failure, would provide useful estimates of muscle deoxygenation in f-ILD.

METHODS

A total of 25 patients (23 men, 72 ± 8 years; 20 with idiopathic pulmonary fibrosis, lung diffusing capacity for carbon monoxide = 44 ± 11% predicted) and 12 age- and sex-matched healthy controls performed incremental cycling to symptom limitation. Changes in vastus lateralis [HHb] assessed by NIRS were analysed in relation to work rate (WR) and O₂ uptake throughout the exercise.

RESULTS

Patients showed lower exercise capacity than controls (e.g., peak WR = 67 ± 18% vs. 105 ± 20% predicted, respectively; p < 0.001). The [HHb] response profile was typically S-shaped, presenting three distinct phases. Exacerbated muscle deoxygenation in patients versus controls was evidenced by: (i) a steeper mid-exercise [HHb]-WR slope (0.30 ± 0.22 vs. 0.11 ± 0.08 μmol/W; p = 0.008) (Phase 2), and (ii) a larger late-exercise increase in [HHb] (p = 0.002) (Phase 3). Steeper [HHb]-WR slope was associated with lower peak WR (r = -0.70) and greater leg discomfort (r = 0.77; p < 0.001) in f-ILD.

CONCLUSION

This practical approach to interpreting [HHb] during incremental exercise might prove useful to determine the severity of muscle deoxygenation and the potential effects of interventions thereof in hypoxemic patients with f-ILD.

Navigational Bronchoscopy with Cryobiopsy for Diagnosis of ILD

Background

Interstitial lung diseases (ILDs) are a group of parenchymal pulmonary diseases in which pathologic diagnosis is essential. Although cryobiopsy has a high diagnostic yield, the complication rate remains high. Case Presentation. We report two cases of lung cryobiopsy guided by navigational bronchoscopy (LCB) for the diagnosis of ILD. In both cases, a CT chest angiogram (CTA) using a navigational protocol was performed. Targets were premarked and reached with the navigational system. Radial ultrasound (RU) was applied in combination with fluoroscopy guidance (FG) prior to sampling. Both patients achieved a final diagnosis; they were discharged home after procedure and no complications were noted. Discussion. By using a CTA with navigational guidance, we were able to perform cryobiopsy in areas with most disease activity and least vascularization.

Conclusion

LCB used with navigational guidance for the diagnosis of ILD provides may be a safe and effective procedure that provides high diagnostic yield. Limitations include cost, availability, and expertise. Larger trials are needed to confirm the additional benefit.

Comparing outcomes of ILD patients managed in specialised versus non-specialised centres

Background

Early appropriate diagnosis and treatment of interstitial lung diseases (ILD) is crucial to slow disease progression and improve survival. Yet it is unknown whether initial management in an expert centre is associated with improved outcomes. Therefore, we assessed mortality, hospitalisations and health care costs of ILD patients initially diagnosed and managed in specialised ILD centres versus non-specialised centres and explored differences in pharmaceutical treatment patterns.

Methods

An epidemiological claims data analysis was performed, including patients with different ILD subtypes in Germany between 2013 and 2018. Classification of specialised centres was based on the number of ILD patients managed and procedures performed, as defined by the European Network on Rare Lung Diseases. Inverse probability of treatment weighting was used to adjust for covariates. Mortality and hospitalisations were examined via weighted Cox models, cost differences by weighted gamma regression models and differences in treatment patterns with weighted logistic regressions.

Results

We compared 2022 patients managed in seven specialised ILD centres with 28,771 patients managed in 1156 non-specialised centres. Specialised ILD centre management was associated with lower mortality (HR: 0.87, 95% CI 0.78; 0.96), lower all-cause hospitalisation (HR: 0.93, 95% CI 0.87; 0.98) and higher respiratory-related costs (€669, 95% CI €219; €1156). Although risk of respiratory-related hospitalisations (HR: 1.00, 95% CI 0.92; 1.10) and overall costs (€− 872, 95% CI €− 75; €1817) did not differ significantly, differences in treatment patterns were observed.

Conclusion

Initial management in specialised ILD centres is associated with improved mortality and lower all-cause hospitalisations, potentially due to more differentiated diagnostic approaches linked with more appropriate ILD subtype-adjusted therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02143-1.

Disease activity of lung cancer at the time of acute exacerbation of interstitial lung disease during cytotoxic chemotherapy

Background

The prognosis of lung cancer patients with interstitial lung disease (ILD) is poor, and acute exacerbation (AE) of ILD can occur during chemotherapy as a fatal adverse event. Although AE‐ILD development is correlated with various factors, no reports are investigating the disease activity of lung cancer at the time of AE‐ILD development.

Methods

All consecutive lung cancer patients with ILD who developed chemotherapy‐related AE‐ILD within 28 days after the last administration of cytotoxic chemotherapy between 2011 and 2020 were retrospectively reviewed.

Results

Among 206 lung cancer patients with ILD who were treated with cytotoxic chemotherapy, 30 patients were included. The median age was 72 years and all patients were men with smoking history. Usual interstitial pneumonia (UIP) and non‐UIP patterns of ILD was observed in 17 and 13 patients. Most of AE‐ILD occurred during second‐ or later‐line (22/30, 73.3%) and developed within first or second courses during chemotherapy (19/30, 63.3%). Regarding tumor response to chemotherapy at AE‐ILD development, majority of patients (18 patients, 60.0%) experienced progressive disease and only one patient (3.3%) experienced a partial response. Notably, 27 patients (90.0%) did not exhibit any tumor shrinkage of the thoracic lesions.

Conclusion

Lung cancer was uncontrolled with cytotoxic chemotherapy at the time of AE‐ILD development. Although AE‐ILD during chemotherapy has been generally discussed in terms of drug‐specific adverse effects, uncontrolled lung cancer may be also correlated with AE‐ILD development.

The state of the art for artificial intelligence in lung digital pathology

Lung diseases carry a significant burden of morbidity and mortality worldwide. The advent of digital pathology (DP) and an increase in computational power have led to the development of artificial intelligence (AI)-based tools that can assist pathologists and pulmonologists in improving clinical workflow and patient management. While previous works have explored the advances in computational approaches for breast, prostate, and head and neck cancers, there has been a growing interest in applying these technologies to lung diseases as well. The application of AI tools on radiology images for better characterization of indeterminate lung nodules, fibrotic lung disease, and lung cancer risk stratification has been well documented. In this article, we discuss methodologies used to build AI tools in lung DP, describing the various hand-crafted and deep learning-based unsupervised feature approaches. Next, we review AI tools across a wide spectrum of lung diseases including cancer, tuberculosis, idiopathic pulmonary fibrosis, and COVID-19. We discuss the utility of novel imaging biomarkers for different types of clinical problems including quantification of biomarkers like PD-L1, lung disease diagnosis, risk stratification, and prediction of response to treatments such as immune checkpoint inhibitors. We also look briefly at some emerging applications of AI tools in lung DP such as multimodal data analysis, 3D pathology, and transplant rejection. Lastly, we discuss the future of DP-based AI tools, describing the challenges with regulatory approval, developing reimbursement models, planning clinical deployment, and addressing AI biases. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Predicting checkpoint inhibitors pneumonitis in non-small cell lung cancer using a dynamic online hypertension nomogram

OBJECTIVES

Checkpoint inhibitors pneumonitis (CIP) is one of the most lethal adverse events in non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs). Currently, there is no recognized and effective predictive model to predict CIP in NSCLC.

MATERIALS AND METHODS

This study retrospectively analyzed 460 NSCLC patients who were first treated with ICIs. Patients were divided into three cohorts based on the occurrence of CIP: any grade CIP cohort, grade ≥ 2 CIP cohort and grade ≥ 3 CIP cohort.

RESULTS

A dynamic hypertension nomogram was constructed with elements including hypertension, interstitial lung disease (ILD), emphysema at baseline, and higher baseline platelet/lymphocyte ratio (PLR). The C indices of the training cohort and the internal and external validation cohort in any grade CIP cohort were 0.872, 0.833 and 0.840, respectively. The constructed hypertension nomogram was applied to grade ≥ 2 cohort and grade ≥ 3 cohort, and their C indices were 0.844 and 0.866, respectively. Compared with the non-hypertension nomogram, the hypertension nomogram presented better predictive power.

CONCLUSIONS

After validated by internal and external validation cohorts, the dynamic online hypertension has the potential to become a convenient, intuitive, and personalized clinical tool for assessing the risk of CIP in NSCLC patients.

Performance of Lung Ultrasound for Monitoring Interstitial Lung Disease

OBJECTIVES

In this study, we sought to assess the validity of lung ultrasound (LUS) during the follow-up of patients with a wide spectrum of interstitial lung diseases (ILDs).

METHODS

Twenty-four patients (13 males, 11 females; mean age ± SD, 65.4 ± 14.3 years; age range, 40-84 years) with a diagnosis of ILDs who were admitted to the Interstitial Lung Disease Unit were prospectively enrolled. Patients were examined with a 56-lung intercostal space LUS protocol in lateral decubitus position, at baseline, 6-months, and 1-year. The LUS score was defined as the sum of B-lines counted in each intercostal space. All patients underwent complete pulmonary function tests at baseline and follow-up time-points. High-resolution computed tomography (HRCT) was performed at baseline and during follow-up, according to personalized patients' needs. All HRCT studies were graded according to the Warrick scoring system (WS).

RESULTS

Pooled data analysis showed a significant correlation between WS and LUS scores (P < .001). For separate time-point analysis, a significant correlation between LUS scores and WS was found at baseline (P < .001) and 1 year (P = .005). LUS scores negatively correlated with alveolar volume (VA) (P < .046) and diffusing capacity for carbon monoxide (DLCO) (P < .001) at 6 months and with transfer coefficient of the lung for carbon monoxide (KCO) (P < .031) and DLCO (P = .002) at 12-months. A multivariate regression model showed DLCO to be an independent predictor of LUS score at 1 year (P = .026).

CONCLUSIONS

Our results highlight the validity and potential applicability of LUS for disease monitoring in a wide spectrum of ILDs.

Effects of Influenza Vaccination in Patients with Interstitial Lung Diseases: An Epidemiological Claims Data Analysis

Rationale

Vaccination is the most effective protection against influenza. Patients with interstitial lung diseases (ILDs) represent a high-risk group for influenza complications. Thus, yearly influenza vaccination is recommended, but evidence on its effects is sparse.

Objectives

This study aimed to compare all-cause mortality and all-cause and respiratory-related hospitalization between vaccinated and unvaccinated patients with ILD.

Methods

Using data from the largest German statutory health insurance fund (about 27 million insurees in 2020), we analyzed four influenza seasons from 2014–2015 to 2017–2018 and compared vaccinated with unvaccinated patients with ILD. Starting from September 1 of each year, we matched vaccinated and unvaccinated patients in a 1:1 ratio using a rolling cohort design. Mortality and hospitalization were compared with Kaplan-Meier plots, and effects were calculated during the influenza season (in season) with risk ratios.

Results

Both the vaccinated and the unvaccinated cohorts included 7,503 patients in 2014–2015, 10,318 in 2015–2016, 12,723 in 2016–2017, and 13,927 in 2017–2018. Vaccination rates were low at 43.2% in season 2014–2015 and decreased over time to 39.9% in season 2017–2018. The risk ratios for all-cause mortality were 0.79 (95% confidence interval [CI], 0.65–0.97; P = 0.02) in season 2014–2015, 0.66 (95% CI, 0.54–0.80; P < 0.001) in 2015–2016, 0.89 (95% CI, 0.76–1.04; P = 0.15) in 2016–2017, and 0.95 (95% CI, 0.81–1.12; P = 0.57) in 2017–2018. The effects on all-cause hospitalization and respiratory-related hospitalization were similar in all seasons.

Conclusions

Although an unequivocally beneficial impact of influenza vaccination in patients with ILD could not be demonstrated, we observed promising results regarding avoidance of all-cause mortality in half of the seasons observed. Given the low vaccination rates, further efforts are necessary to improve vaccination rates in patients with ILD.

Discrimination between NSIP- and IPF-Derived Fibroblasts Based on Multi-Parameter Characterization of Their Growth, Morphology and Physic-Chemical Properties

Background: The aim of the research presented here was to find a set of parameters enabling discrimination between three types of fibroblasts, i.e., healthy ones and those derived from two disorders mimicking each other: idiopathic pulmonary fibrosis (IPF), and nonspecific interstitial pneumonia (NSIP). Methods: The morphology and growth of cells were traced using fluorescence microscopy and analyzed quantitatively using cell proliferation and substrate cytotoxicity indices. The viability of cells was recorded using MTS assays, and their stiffness was examined using atomic force microscopy (AFM) working in force spectroscopy (FS) mode. To enhance any possible difference in the examined parameters, experiments were performed with cells cultured on substrates of different elasticities. Moreover, the chemical composition of cells was determined using time-of-flight secondary ion mass spectrometry (ToF-SIMS), combined with sophisticated analytical tools, i.e., Multivariate Curve Resolution (MCR) and Principal Component Analysis (PCA). Results: The obtained results demonstrate that discrimination between cell lines derived from healthy and diseased patients is possible based on the analysis of the growth of cells, as well as their physical and chemical properties. In turn, the comparative analysis of the cellular response to altered stiffness of the substrates enables the identification of each cell line, including distinguishing between IPF- and NSIP-derived fibroblasts.

Caring for a parent with pulmonary fibrosis in Malta: The lived experiences of daughters in mid-adulthood

Idiopathic pulmonary fibrosis is a progressive fibrotic lung disease that is on the rise globally. The disease is associated with significant morbidity and hence poses significant challenges for their informal carers, particularly daughters in mid-adulthood, who struggle with their own personal demands and that of their ill parents. Yet there is a dearth of literature on the experiences of these specific carers. Hence, the purpose of this study is to explore the lived experiences of daughters caring for a parent with pulmonary fibrosis within a community setting. This was explored using a phenomenological qualitative framework that was conducted between January and April 2017. Semi-structured audio-recorded interviews were conducted with six adult daughters who provided care to a parent having pulmonary fibrosis. Purposive sampling was used to recruit study participants. Transcribed data were analysed using Interpretative Phenomenological Analysis. Three main themes were extracted which communicate the essence of the daughters' lived experiences: "Walking on tiptoes", "Flooded by emotions" and "Shifts in family dynamics." Participants described experiencing the toll of being constantly vigilant for symptoms. They also expressed a range of emotions that included guilt, helplessness and worry related to their care experience. However, these emotional struggles were suppressed in order to present an external facade of strength and control. A shift in roles was also described where the daughters became the informal carers/support for both their ill and well parent, albeit in different ways. Caring for a person with pulmonary fibrosis is an emotional and life changing experience and hence, there is the need for individualised interventions that target the unique perceptions of these informal carers.

Cardiopulmonary exercise testing in interstitial lung diseases and the value of ventilatory efficiency

Interstitial lung diseases (ILDs) are diverse parenchymal pulmonary disorders, primarily characterised by alveolar and interstitial inflammation and/or fibrosis, and sharing pathophysiological similarities. Thus, patients generally harbour common respiratory symptoms, lung function abnormalities and modified exercise adaptation. The most usual and disabling complaint is exertional dyspnoea, frequently responsible for premature exercise interruption. Cardiopulmonary exercise testing (CPET) is increasingly used for the clinical assessment of patients with ILD. This is because exercise performance or dyspnoea on exertion cannot reliably be predicted by resting pulmonary function tests. CPET, therefore, provides an accurate evaluation of functional capacity on an individual basis. CPET can unmask anomalies in the integrated functions of the respiratory, cardiovascular, metabolic, peripheral muscle and neurosensory systems in ILDs. CPET uniquely provides an evaluation of all above aspects and can help clinicians shape ILD patient management. Preliminary evidence suggests that CPET may also generate valuable prognostic information in ILDs and can be used to shed light on the presence of associated pulmonary hypertension. This review aims to provide comprehensive and updated evidence concerning the clinical utility of CPET in ILD patients, with particular focus on the physiological and clinical value of ventilatory efficiency (V˙_E/V˙_CO2 ).

The effect of heated humidified nasal high flow oxygen supply on exercise tolerance in patients with interstitial lung disease: A pilot study

BACKGROUND AND OBJECTIVES

Patients with interstitial lung disease (ILD) experience early symptoms of dyspnoea and leg fatigue during exercise together with severe and rapid oxygen desaturation. Heated and humidified nasal high flow oxygen (NHF) has been proven to enhance exercise endurance and physiological parameters in COPD patients. This study aims to evaluate the effect of NHF on exercise tolerance in ILD patients.

METHODS

Twenty-five patients (10 female) with severe ILD performed three constant-load (70% maximal workload) cycling tests to exhaustion under different breathing conditions: room air, oxygen supplementation (4 L min^-1 O₂) and NHF (inspiratory O₂ fraction 0.5, 30-50 L min^-1, heated 34 °C and humidified).

RESULTS

Endurance time was significantly longer with NHF (618 ± 297 s) compared to O₂ (369 ± 217 s, p < 0.001) and room air (171 ± 76 s, p < 0.001). Kinetics of oxygen desaturation, chronotropic response, dyspnoea and leg fatigue sensations were delayed with NHF. At exhaustion with NHF, compared to the two other conditions, oxygen desaturation was less severe while heart rate, dyspnoea and leg fatigue were similar.

CONCLUSION

NHF significantly improved endurance time, physiological parameters and sensations during exercise in severe ILD patients. NHF may be useful to improve functional capacities and facilitate pulmonary rehabilitation in ILD.

Inflammatory profile of induced sputum composition in systemic sclerosis and comparison with healthy volunteers

Systemic sclerosis (SSc) is a potentially serious and disabling connective tissue disease specially in case of interstitial lung disease (SSc-ILD). The aim of our study was to evaluate the potential utility of dosing in the induced sputum (IS) and to compare their levels in SSc-ILD and SSc-nonILD patients, as well as in healthy volunteers (HV). IS and sera values were also compared. In a prospective cross-sectional analysis, we studied the IS and serum provided from 25 SSc patients, 15 SSc-nonILD and 10 SSc-ILD, compared to 25 HV. We analyzed sputum cell composition and quantified in the supernatant and corresponding serum by commercially available immunoassays: IGFBP-1, IGFBP-2, IGFBP-3, TGF-β, IL-8, TNF-α, YKL-40, MMP-7 and MMP-9. Lung function was studied by the determination of FEV-1 (%), FVC (%), DLCO (%) and KCO (%). The IS of SSc patients had a lower weight than HV (p<0.05, p<0.01) without any significant difference with regard to the cellularity. IGFBP-1 (p < 0.0001), TGF-β (p < 0.05), IL-8 (p < 0.05), YKL-40 (p < 0.0001) and MMP-7 (p < 0.01) levels were increased in the IS of SSc patients compared to HV. Only IL-8 serum levels (p < 0.001) were increased in SSc patients compared to HV. Neither in IS nor in serum were observed differences between SSc-ILD and SSc-nonILD patients. Correlations were observed between IS IL-8 levels and FEV-1 (%) (r =  = − 0.53, p < 0.01), FVC (%) (r = − 0.51, p < 0.01) and annualized ∆KCO (%) (r = 0.57, p < 0.05), between IS TGF-β levels and annualized ∆FEV-1 (%) (r =  = − 0.57, p < 0.05), between IS IGFBP-2 levels and annualized ∆KCO (%) (r = 0.56, p < 0.05). Our study showed that SSc patients exhibit raised IS levels of IGFBP-1, TGF-β, IL-8, YKL-40 and MMP-7, molecules known to be involved in lung remodeling and fibrotic process, without any significant difference between SSc-ILD and SSc-nonILD patients. IL-8, TGF-β and IGFBP-2 are correlated with lung function in SSc patients which emphasize clinical relevance. IS analysis represents a new approach to understand lung inflammatory process in SSc patients. A longitudinal study is needed to evaluate their pathophysiological relevance.

Study protocol for a randomised, placebo-controlled, single-blind phase II study of the efficacy of morphine for dyspnoea in patients with interstitial lung disease (JORTC-PAL 15)

INTRODUCTION

Dyspnoea is common in patients with interstitial lung disease (ILD) and often refractory to conventional treatment. Little is known about the efficacy of systemic morphine for dyspnoea in patients with ILD. The aim of this study is to estimate the efficacy of a single subcutaneous morphine injection for dyspnoea in patients with ILD.

METHODS AND ANALYSIS

We will conduct a multicentre, prospective, randomised, placebo-controlled, single-blinded phase II study of a single subcutaneous morphine injection for dyspnoea in patients with ILD. In patients with ILD who have dyspnoea at rest refractory to conventional treatment will be eligible for participation in this study. The morphine dose will be 2 mg. The primary endpoint is changes in dyspnoea intensity from baseline to 60 min after treatment as measured using an 11-point Numerical Rating Scale and compared between the morphine and placebo groups.

ETHICS AND DISSEMINATION

Ethical approval has been obtained by the Osaka City University Certified Review Board. The results of this study will be submitted for publication in an international peer-reviewed journal and the findings will be presented at international scientific conferences.

TRIAL REGISTRATION NUMBER

jRCTs051190030; pre-results.

Functional performance tests in interstitial lung disease: Impairment and measurement properties

BACKGROUND

There is limited information regarding impairment in functional performance tests and their measurement properties in ILD. The present study aimed to verify the impairment and measurement properties of functional performance tests in ILD.

METHODS

ILD and healthy individuals underwent assessments of pulmonary function, peripheral muscle strength (handgrip force and maximum isometric contraction of quadriceps femoris - MIVCq) and exercise capacity (6-min walk test - 6MWT). Functional performance was assessed by timed-up-and-go with usual (TUGu) and fast (TUGf) gait speeds, 4-m gait speed (4MGS), sit-to-stand in 30 s (30sec-STS), 1 min (1min-STS) and with 5 repetition (5rep-STS) and Short Physical Performance Battery (SPPB). Functional performance was compared between groups, validity (correlation with 6MWT and MIVCq) and reliability of tests were checked in subjects with ILD (intra- and inter-rater agreement analysis).

RESULTS

Seventy-six participants (40 ILD [25 women, 61 ± 11 years, FVC 75 ± 17 %pred] and 36 healthy [22 women, 61 ± 9 years, FVC 97 ± 11 %pred]) were included. Functional performance in ILD was worse than in healthy individuals in all tests, except for the 30sec-STS (p = 0.13). Pre-specified validity criteria were reached for TUGu, TUGf, 4MGS and 5rep-STS (-0.69 < r < 0.55; p < 0.05 for all). Except for 4MGS and SPPB, all tests showed good to excellent inter-rater (0.85 < ICC<0.93; p < 0.05 for all) and all tests showed good to excellent intra-rater (0.83 < ICC< 0.94; p < 0.05 for all) reliability.

CONCLUSIONS

Subjects with ILD present worse functional performance than healthy individuals. According to reliability and validity results, TUGu, TUGf and 5rep-STS seem to be the most appropriate tests to evaluate functional performance in ILD.

Oxygen supplementation during exercise improves leg muscle fatigue in chronic fibrotic interstitial lung disease

BACKGROUND

Exercise-induced hypoxaemia is a hallmark of chronic fibrotic interstitial lung disease (f-ILD). It remains unclear whether patients' severe hypoxaemia may exaggerate locomotor muscle fatigue and, if so, to what extent oxygen (O₂) supplementation can ameliorate these abnormalities.

METHODS

Fifteen patients (12 males, 9 with idiopathic pulmonary fibrosis) performed a constant-load (60% peak work rate) cycle test to symptom limitation (Tlim) while breathing medical air. Fifteen age-matched and sex-matched controls cycled up to patients' Tlim. Patients repeated the exercise test on supplemental O₂ (42%±7%) for the same duration. Near-infrared spectroscopy assessed vastus lateralis oxyhaemoglobin concentration ((HbO₂)). Pre-exercise to postexercise variation in twitch force (∆Tw) induced by femoral nerve magnetic stimulation quantified muscle fatigue.

RESULTS

Patients showed severe hypoxaemia (lowest O₂ saturation by pulse oximetry=80.0%±7.6%) which was associated with a blunted increase in muscle (HbO₂₎ during exercise vs controls (+1.3±0.3 µmol vs +4.4±0.4 µmol, respectively; p<0.001). Despite exercising at work rates ∼ one-third lower than controls (42±13 W vs 66±13 W), ∆Tw was greater in patients (∆Tw/external work performed by the leg muscles=-0.59±0.21 %/kJ vs -0.25±0.19 %/kJ; p<0.001). Reversal of exertional hypoxaemia with supplemental O₂ was associated with a significant increase in muscle (HbO₂₎, leading to a reduced decrease in ∆Tw in patients (-0.33±0.19 %/kJ; p<0.001 vs air). Supplemental O₂ significantly improved leg discomfort (p=0.005).

CONCLUSION

O₂ supplementation during exercise improves leg muscle oxygenation and fatigue in f-ILD. Lessening peripheral muscle fatigue to enhance exercise tolerance is a neglected therapeutic target that deserves clinical attention in this patient population.

The Association between MUC5B Rs35705950 and Risks of Idiopathic Interstitial Pneumonia, Systemic Sclerosis Interstitial Lung Disease, and Familial Interstitial Pneumonia: A Meta-Analysis

Background:

Interstitial lung disease (ILD) is a category of chronic lung diseases with more than 200 subtypes. Idiopathic interstitial pneumonia (IIP), systemic sclerosis (SSc) ILD, and familial interstitial pneumonia (FIP) are three major groups of lung diseases with different causes or with unknown causes. Mucin5B (MUC5B) belongs to the mucin family, which contribute to the lubricating and viscoelastic properties of the whole saliva, normal lung mucus, and cervical mucus. The association between MUC5B rs35705950 and ILDs risks has been widely studied. However, the results were inconclusive and inconsistent.

Methods:

In the present meta-analysis, the database PubMed, Embase, Cochrane Central Register of Controlled Trials, CNKI and Chinese Biomedical Literature Database were searched till Aug 20^th, 2018. Overall 16 publications with 28 studies, 76345 cases and 18402 controls were included.

Results:

The results indicated a significant increase of overall IIP risk for TT genotype and T allele of the rs35705950 in all genetic models (TT vs GG, OR=9.11; TT vs GT+TT, OR=5.80; GT+TT vs GG, OR=4.34; T vs G, OR=4.03. P<0.0001). Subgroup analysis by subtypes of IIP revealed higher risks of TT genotype and T allele for IPF and iNSIP (P<0.05). A significant increase of FIP risk was also found for the TT genotype and T allele of the rs35705950 (TT vs GG, OR=17.08; GT+TT vs GG, OR=6.02; T vs G, OR=1.64.P<0.05).

Conclusion:

No significant relations existed between the rs35705950 and SSc-ILD risks. MUC5B rs35705950 might be a predictor for the susceptibility of IIP and FIP.

Effect of tuned elasticity and chemical modification of substrate on fibrotic and healthy lung fibroblasts

Response to substrate elasticity, dependent on mechanical properties of cells, differs for lung fibroblast derived from idiopathic pulmonary fibrosis (IPF) and the healthy ones. These altered interactions might potentially act as a 'biomarker' for easy and reliable IPF diagnosis. In this work, systematic studies on the effect of polydimethylsiloxane (PDMS) substrate elasticity, tuned stepwise from 600 kPa to 1.5 MPa on the growth of IPF-derived (LL97A) and healthy (LL24) lung fibroblasts were reported. Additionally, impact of substrate chemistry on both cell lines was studied for fibroblasts cultured on glass substrates modified with three organosilanes - 3-aminopropyltriethoxysilane (APTES), 3-mercaptopropyltriethoxysilane (MPTES) and 3-glycidyloxypropyl trimethoxysilane (GOPS), with different end groups. Finally, the effect of the simultaneous modification of mechanical and chemical properties on the cellular behavior was studied for fibroblast cultured on PDMS substrates covered with silanes. The growth of cells was traced using fluorescence microscopy and analyzed quantitatively by nucleus-cytoplasm ratio, indicating strong, cell-dependent impact of substrate elasticity dominating over effect of chemical modification.

Effect of Substrate Stiffness on Physicochemical Properties of Normal and Fibrotic Lung Fibroblasts

The presented research aims to verify whether physicochemical properties of lung fibroblasts, modified by substrate stiffness, can be used to discriminate between normal and fibrotic cells from idiopathic pulmonary fibrosis (IPF). The impact of polydimethylsiloxane (PDMS) substrate stiffness on the physicochemical properties of normal (LL24) and IPF-derived lung fibroblasts (LL97A) was examined in detail. The growth and elasticity of cells were assessed using fluorescence microscopy and atomic force microscopy working in force spectroscopy mode, respectively. The number of fibroblasts, as well as their shape and the arrangement, strongly depends on the mechanical properties of the substrate. Moreover, normal fibroblasts remain more rigid as compared to their fibrotic counterparts, which may indicate the impairments of IPF-derived fibroblasts induced by the fibrosis process. The chemical properties of normal and IPF-derived lung fibroblasts inspected using time-of-flight secondary ion mass spectrometry, and analyzed complexly with principal component analysis (PCA), show a significant difference in the distribution of cholesterol and phospholipids. Based on the observed distinctions between healthy and fibrotic cells, the mechanical properties of cells may serve as prospective diagnostic biomarkers enabling fast and reliable identification of idiopathic pulmonary fibrosis (IPF).

The Efficacy and Safety of First-Line Chemotherapy in Patients With Non-small Cell Lung Cancer and Interstitial Lung Disease: A Systematic Review and Meta-Analysis

Background: Lung cancer is a well-known comorbidity of interstitial lung disease (ILD), and the actual efficacy and safety of chemotherapy for patients with non-small cell lung cancer and interstitial lung disease (NSCLC-ILD) have not been determined. We conducted this meta-analysis to assess the efficacy and safety of chemotherapy for patients with NSCLC-ILD.

Methods: We searched related studies from the Cochrane Library, PubMed, and Embase. The endpoints were objective response rate (ORR), disease control rate (DCR), 1-year overall survival rate (1-yOS rate), and first-line chemotherapy-related acute exacerbation of interstitial lung disease rate (AE-ILD rate).

Results: We included 21 studies involving 684 patients in our analysis. The pooled ORR was 43% (95% CI: 38.0–49.0%), and the pooled DCR was 80.0% (95% CI: 75.7–83.9%). The modified overall 1-yOS rate was 33.0% (95% CI: 29.0–37.0%). The pooled AE-ILD rate was 8.07% (95% CI: 6.12–10.26%). Subgroup analysis revealed a trend for lower AE-ILD rate (4.98%; 95% CI: 2.44–8.37%) in patients with carboplatin plus nab-paclitaxel. Lung function and AE-ILD may be associated with the prognosis of patients with NSCLC-ILD.

Conclusions: First-line chemotherapy is effective in patients with NSCLC-ILD, and the AE-ILD rate is acceptable, but the prognosis is limited. Future randomized controlled trials are needed to explore more appropriate treatment regimens to improve the prognosis of patients with NSCLC-ILD.

Supplemental oxygen for the management of dyspnea in interstitial lung disease

PURPOSE OF REVIEW

This article presents a summary of the evidence relating to supplemental oxygen use for the management of dyspnea in patients with interstitial lung disease (ILD).

RECENT FINDINGS

In contrast to the majority of the available literature, recent findings suggest that supplemental oxygen can significantly reduce exertional dyspnea in ILD. ILD patients' need for supplemental oxygen often surpasses the levels that the most commonly used oxygen delivery systems provide. More effective delivery of supplemental oxygen has the potential for greater relief of dyspnea. There is also evidence suggesting that indications for supplemental oxygen may differ in ILD compared with other chronic lung diseases.

SUMMARY

Large clinical trials are needed to determine if the reductions in dyspnea with supplemental oxygen observed in the laboratory setting can translate into meaningful benefits in everyday life for patients with ILD. More effective and practical oxygen delivery systems are needed. Future guidelines should consider including recommendations addressing the potential role of supplemental oxygen for mildly hypoxemic patients with ILD as well as recommendations specific to supplemental oxygen use for exercise training in ILD.

Therapeutic potential of targeting kinase inhibition in patients with idiopathic pulmonary fibrosis

Fibrosis is characterized by excessive accumulation of extracellular matrix components. The fibrotic process ultimately leads to organ dysfunction and failure in chronic inflammatory and metabolic diseases such as pulmonary fibrosis, advanced kidney disease, and liver cirrhosis. Idiopathic pulmonary fibrosis (IPF) is a common form of progressive and chronic interstitial lung disease of unknown etiology. Pathophysiologically, the parenchyma of the lung alveoli, interstitium, and capillary endothelium becomes scarred and stiff, which makes breathing difficult because the lungs have to work harder to transfer oxygen and carbon dioxide between the alveolar space and bloodstream. The transforming growth factor beta (TGF-β) signaling pathway plays an important role in the pathogenesis of pulmonary fibrosis and scarring of the lung tissue. Recent clinical trials focused on the development of pharmacological agents that either directly or indirectly target kinases for the treatment of IPF. Therefore, to develop therapeutic targets for pulmonary fibrosis, it is essential to understand the key factors involved in the pathogenesis of pulmonary fibrosis and the underlying signaling pathway. The objective of this review is to discuss the role of kinase signaling cascades in the regulation of either TGF-β-dependent or other signaling pathways, including Rho-associated coiled-coil kinase, c-jun N-terminal kinase, extracellular signal-regulated kinase 5, and p90 ribosomal S6 kinase pathways, and potential therapeutic targets in IPF.

Cardiopulmonary Exercise Testing in Patients With Interstitial Lung Disease

Interstitial lung disease (ILD) is a heterogeneous group of conditions characterized by fibrosis and/or inflammation of the lung parenchyma. The pathogenesis of ILD consistently results in exertional dyspnea and exercise intolerance. Cardiopulmonary exercise testing (CPET) provides important information concerning the pathophysiology of ILD that can help inform patient management. Despite the purported benefits of CPET, its clinical utility in ILD is not well defined; however, there is a growing body of evidence that provides insight into the potential value of CPET in ILD. Characteristic responses to CPET in patients with ILD include exercise-induced arterial hypoxemia, an exaggerated ventilatory response, a rapid and shallow breathing pattern, critically low inspiratory reserve volume, and elevated sensations of dyspnea and leg discomfort. CPET is used in ILD to determine cause(s) of symptoms such as exertional dyspnea, evaluate functional capacity, inform exercise prescription, and determine the effects of pharmacological and non-pharmacological interventions on exercise capacity and exertional symptoms. However, preliminary evidence suggests that CPET in ILD may also provide valuable prognostic information and can be used to ascertain the degree of exercise-induced pulmonary hypertension. Despite these recent advances, additional research is required to confirm the utility of CPET in patients with ILD. This brief review outlines the clinical utility of CPET in patients with ILD. Typical patterns of response are described and practical issues concerning CPET interpretation in ILD are addressed. Additionally, important unanswered questions relating to the clinical utility of CPET in the assessment, prognostication, and management of patients with ILD are identified.

Overview of the ChILD Research Network: A roadmap for progress and success in defining rare diseases

Children's interstitial and diffuse lung diseases are a diverse group of rare lung disorders that present in childhood with diffuse pulmonary infiltrates and respiratory signs and symptoms. Children with these disorders face high morbidity and mortality and their families must cope with overwhelming uncertainty. Physicians caring for these patients are challenged by a paucity of directed therapies, or even understanding of natural history. Through the establishment of the Children's Interstitial Lung Disease Foundation Research Network and the Children's Interstitial Lung Disease Foundation significant progress has been made through collaboration and research. This review outlines the past and current successes in the new and rapidly growing field of Children's Interstitial and Diffuse Lung Disease.

Systematic review and meta-analysis of prognostic factors of acute exacerbation of idiopathic pulmonary fibrosis

OBJECTIVE

To clarify prognostic factors of acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF).

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

Medline, Embase and Science Citation Index Expanded were searched from 2002 through 1 March 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

The review included primary studies addressing the association between the outcomes such as all-cause mortality of AE of IPF and its potential prognostic factors, which were designated as any clinical information related to the outcomes.

DATA EXTRACTION AND SYNTHESIS

Two reviewers extracted relevant data independently and assessed risk of bias. Univariate results were pooled using a random-effect model if at least three studies were available. Prognostic factors were determined based on significant and consistent results on both univariate and multivariate analyses in the majority of studies.

RESULTS

Out of a total of 6763 articles retrieved, 37 were eligible and 31 potential prognostic factors for all-cause mortality were selected. Each study was subject to certain methodological shortcomings. The following five factors were statistically significant by a meta-analysis of univariate results, which was confirmed by multivariate analysis, that is, Acute Physiology and Chronic Health Evaluation (APACHE) II score (HR 1.10, 1.01 to 1.19), partial pressure of arterial oxygen to fraction of inspired oxygen (PaO₂/FiO₂) ratio (ORs 0.99 in two studies and HRs 0.31 and 0.99 in two studies, respectively), lactate dehydrogenase (LDH) (HRs 1.002, 1.003, 1.01 and 1.02), white blood cell (WBC) count (OR 1.38, 1.04 to 1.83) and oxygen therapy before AE (HRs 3.68, 1.05 to 12.9 and 2.34, 1.04 to 5.28) (multivariate analysis, 95% CI).

CONCLUSIONS

APACHE II score, PaO₂/FiO₂ ratio, LDH, WBC count and oxygen therapy before AE were deemed as prognostic factors of AE of IPF. Although there are some methodological limitations in this study, these findings are reliable due to consistent results by both univariate and multivariate analyses.

PROSPERO REGISTRATION NUMBER

CRD42018106172.

Effects of adopting the Global Lung Function Initiative 2017 reference equations on the interpretation of carbon monoxide transfer factor

The recently published Global Lung Function Initiative (GLI) carbon monoxide transfer factor (T _LCO) reference equations provide an opportunity to adopt a current, all-age, widely applicable reference set. The aim of this study was to document the effect of changing to GLI from commonly utilised reference equations on the interpretation of T _LCO results.33 863 T _LCO results (48% female, 88% Caucasian, n=930 aged <18 years) from clinical pulmonary function laboratories within three Australian teaching hospitals were analysed. The lower limit of normal (LLN) and proportion of patients with a T _LCO below this value were calculated using GLI and other commonly used reference equations.The average T _LCO LLN for GLI was similar or lower than the other equations, with the largest difference seen for Crapo equations (median: -1.25, IQR: -1.64, -0.86 mmol·min^-1·kPa^-1). These differences resulted in altered rates of reduced T _LCO for GLI particularly for adults (+1.9% versus Miller to -27.6% versus Crapo), more so than for children (-0.8% versus Kim to -14.2% versus Cotes). For adults, the highest raw agreement for GLI was with Miller equations (94.7%), while for children it was with Kim equations (98.1%). Results were reclassified from abnormal to normal more frequently for younger adults, and for adult females, particularly when moving from Roca to GLI equations (30% of females versus 16% of males).The adoption of GLI T _LCO reference equations in adults will result in altered interpretation depending on the equations previously used and to a greater extent in adult females. The effect on interpretation in children is less significant.

[A Review of Drug Therapy of Lung Cancer with Interstitial Lung Disease]

Interstitial lung disease (ILD) is a risk factor for lung cancer. Patients with lung cancer associated with ILD (LC-ILD) often appear clinically. During the treatment of LC-ILD, there is a risk of causing acute exacerbation or even death in the treatment of lung cancer. At the same time, combining ILD has become the exclusion criteria for prospective clinical trials of most lung cancers. Therefore, when lung cancer is combined with ILD, it often becomes a difficult point for the treatment of lung cancer. Because LC-ILD patients have a certain proportion in the clinic, it is necessary to explore the best treatment options. Here we review the results of existing clinical studies for reference.

Diagnostic and prognostic predictive values of circulating KL-6 for interstitial lung disease: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Past investigations showed inconsistent results for diagnostic and prognostic predictive values of Krebs von den Lungen-6 (KL-6) for interstitial lung disease (ILD).

METHODS

Web of Science and PubMed were systematically searched on for articles exploring the association of KL-6 and ILDs published between September 1993 and March 2019. For comparisons between-groups, the standard mean difference and 95% confidence intervals (CIs) were computed as the effect sizes. For diagnostic studies, a summary of sensitivity, specificity, positive likelihood ratios, negative likelihood ratios, and diagnostic odds ratio, which indicated the accuracy of KL-6 in the differentiation of ILDs and no ILDs, were calculated from the true positive, true negative, false positive, and false negative of each study. In addition, the summary receive-operating characteristics curve was constructed to summarize the TP and FP rates. For follow-up study, we computed hazard ratios (HRs) and 95% CIs for mortality. ILD patients showed elevated concentrations of KL-6, compared to healthy controls and patients without ILD.

RESULTS

The meta-analysis showed a sensitivity (0.85 [95% CI: 0.77-0.91]) and specificity (0.97 [95% CI: 0.90-0.99]) of KL-6 for ILDs. In addition, it showed elevated baseline circulating levels of KL-6 in subsequent active ILD, compared to subsequent inactive ILD. Moreover, there was a significant association between baseline levels of circulating KL-6 and mortality of ILD (HR 2.95, 95% CI 2.45-3.55, I = 65.9%, P = .032).

CONCLUSION

In conclusion, the study suggested that circulating KL-6 showed diagnostic and prognostic predictive values for ILDs.