Usual Interstitial Pneumonia Pattern Research Articles

High resolution computed tomography in systemic sclerosis: From diagnosis to follow-up.

Early diagnosis of interstitial lung disease (ILD) and pulmonary hypertension (PH) is crucial in systemic sclerosis (SSc) for both management and treatment. However, diagnosing SSc-ILD can be challenging because symptoms of lung involvement are often non-specific at the early stages of disease. High-resolution computed tomography (HRCT) of the chest is recognized as the most accurate imaging modality for baseline and follow-up evaluation of SSc-ILD. Key features of SSc-ILD on HRCT include a non-specific interstitial pneumonia (NSIP) pattern, with peripheral ground-glass opacities and extensive traction bronchiectasis. Less common HRCT manifestations include usual interstitial pneumonia (UIP) pattern, followed by diffuse alveolar damage (DAD), diffuse alveolar hemorrhage (DAH) and organizing pneumonia (OP). The extent of disease on HRCT is known to relate with prognosis and serial assessments can be helpful in monitoring disease progression or treatment response. We discuss the main chest computed tomography (CT) manifestations of SSc, highlighting the role of imaging at both baseline and follow-up evaluations.

Deep-learning CT imaging algorithm to detect usual interstitial pneumonia pattern in patients with systemic sclerosis-associated interstitial lung disease: association with disease progression and survival.

Interstitial lung disease (ILD) is the most common cause of death in patients with systemic sclerosis (SSc), although disease behavior is highly heterogeneous. While a usual interstitial pneumonia (UIP) pattern is associated with worse survival in other ILDs, its significance in SSc-ILD is unclear. We sought to assess the prognostic utility of a deep-learning HRCT algorithm of UIP probability in SSc-ILD. Patients with SSc-ILD were included if HRCT images, concomitant lung function tests, and follow-up data were available. We used the Systematic Objective Fibrotic Imaging analysis Algorithm (SOFIA), a convolution neural network algorithm which provides probabilities of a UIP pattern on HRCT images. These were converted into the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED)-based UIP probability categories. Decline in lung function was assessed by mixed-effect model analysis and relationship with survival by Cox proportional hazards analysis. 522 patients were included in the study. 19.5% were classified as UIP not in the differential, 53.5% as low probability of UIP, 25.7% as intermediate probability of UIP, and 1.3% as high probability of UIP. A higher likelihood of UIP probability expressed as PIOPED categories was associated with worse baseline FVC, as well as with decline in FVC (p= 0.008), and worse 15-year survival (p= 0.001), both independently of age, gender, ethnicity, smoking history, and baseline FVC or Goh et al. staging system. A higher probability of a SOFIA-determined UIP pattern is associated with more advanced ILD, disease progression, and worse survival, suggesting that it may be a useful prognostic marker in SSc-ILD.

FAM13A polymorphism is associated with a usual interstitial pneumonia pattern in patients with systemic sclerosis-associated interstitial lung disease.

The MUC5B promoter single nucleotide polymorphism (SNP) rs35705950 has been associated with idiopathic pulmonary fibrosis (IPF) and rheumatoid arthritis (RA)-related interstitial lung disease (ILD), but not with systemic sclerosis (SSc)-ILD. We hypothesized that the MUC5B promoter polymorphism or other IPF susceptibility loci are associated with an increased risk for the uncommon SSc-usual interstitial pneumonia (UIP) endophenotype, rather than SSc-ILD in general. We performed a cross-sectional study of SSc-ILD patients from 4 US Scleroderma Programs to investigate the frequency of MUC5B rs35705950 and 12 additional IPF susceptibility loci. SSc-ILD patients were stratified by high resolution chest CT (HRCT) imaging findings into UIP and non-UIP groups. Analysis of HRCTs performed by a thoracic radiologist blinded to participants' characteristics classified each scan as definite UIP, probable UIP, indeterminate, or alternative diagnosis, according to American Thoracic Society criteria. Four-hundred eighty-nine SSc-ILD patients were included; 80% were female and 75% were White. Twenty-three (4.7%) patients had a definite UIP pattern. The MUC5B SNP rs35705950 was not associated with a definite UIP pattern in SSc-ILD. In contrast, patients carrying 2 copies of the IPF risk gene FAM13A minor allele rs2609255 had significantly higher odds of a definite UIP pattern compared with the other patterns (OR 3.40, 95% CI 1.19-9.70), and compared with an alternative diagnosis (OR 3.65, 95% CI 1.25-10.65). We demonstrated a novel association between FAM13A and SSc-UIP. Contrary to IPF and RA-ILD, the MUC5B promoter polymorphism was not associated with a definite UIP pattern in SSc-ILD.

Quantitative CT-analysis of over aerated lung tissue and correlation with fibrosis extent in patients with idiopathic pulmonary fibrosis

IntroductionThe usual interstitial pneumonia (UIP) pattern, hallmark of idiopathic pulmonary fibrosis (IPF), may induce harmful local overdistension during mechanical ventilation given the juxtaposition of different tissue elasticities. Mechanotransduction, linking mechanical stress and strain to molecular pro-fibrotic pathways, likely contributes to fibrosis progression. Understanding the mechanical forces and aeration patterns in the lungs of IPF patients is crucial for unraveling potential mechanisms of disease progression. Quantitative lung computed tomography (CT) can accurately assess the air content of lung regions, thus informing on zonal distension. This study aims to investigate radiological evidence of lung over aeration in spontaneously breathing UIP patients compared to healthy controls during maximal inspiration.MethodsPatients with IPF diagnosis referred to the Center for Rare Lung Diseases of the University Hospital of Modena (Italy) in the period 2020–2023 who underwent High Resolution Computed Tomography (HRCT) scans at residual volume (RV) and total lung capacity (TLC) using standardized protocols were retrospectively considered eligible. Patients with no signs of lung disease at HRCT performed with the same image acquisition protocol nor at pulmonary function test (PFTs) served as controls. Lung segmentation and quantitative analysis were performed using 3D Slicer software. Lung volumes were measured, and specific density thresholds defined over aerated and fibrotic regions. Comparison between over aerated lung at RV and TLC in the two groups and according to lung lobes was sought. Further, the correlation between aerated lung and the extent of fibrosis was assessed and compared at RV and TLC.ResultsIPF patients (N = 20) exhibited higher over aerated lung proportions than controls (N = 15) both at RV and TLC (4.5% vs. 0.7%, p < 0.0001 and 13.8% vs. 7%, p < 0.0001 respectively). Over aeration increased significantly from RV to TLC in both groups, with no intergroup difference (p = 0.67). Sensitivity analysis revealed significant variations in over aerated lung areas among lobes when passing from RV to TLC with no difference within lobes (p = 0.28). Correlation between over aeration and fibrosis extent was moderate at RV (r = 0.62, p < 0.0001) and weak at TLC (r = 0.27, p = 0.01), being the two significantly different at interpolation analysis (p < 0.0001).ConclusionsThis study provides the first evidence of radiological signs of lung over aeration in patients with UIP-pattern patients when passing from RV to TLC. These findings offer new insights into the complex interplay between mechanical forces, lung structure, and fibrosis and warrant larger and longitudinal investigations.

Meta-Analysis of Interobserver Agreement in Assessment of Interstitial Lung Disease Using High-Resolution CT.

Background High-resolution CT (HRCT) is central to the assessment of interstitial lung disease (ILD), and accurate classification of disease has important implications for patients. Evaluation of imaging features can be challenging, even for experienced thoracic radiologists. Previous work has provided equivocal evidence on the interpretation of HRCT features at ILD-related imaging. Purpose To perform a meta-analysis to assess the level of agreement among expert thoracic radiologists in interpreting ILD-related imaging. Materials and Methods A systematic literature search from January 2000 to October 2023 of the Ovid MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases was performed for articles reporting assessments of interobserver agreement between thoracic radiologists for evaluation of ILD findings, such as severity and progression of disease, presence of features such as honeycombing and ground-glass opacification, and classification based on the 2011 and 2018 American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/Asociación Latinoamericana del Tórax (ATS/ERS/JRS/ALAT) guidelines for idiopathic pulmonary fibrosis (IPF). Meta-analysis was performed using a random-effects model to obtain pooled κ or intraclass correlation coefficient (ICC) values as measures of interobserver agreement. Results The final analysis included 13 studies consisting of 6943 images and 146 radiologists. In 10 studies assessing agreement of specific radiologic findings in ILD, the pooled κ value was 0.56 (95% CI: 0.43, 0.70). In eight studies, the assessed interobserver agreement of the ATS/ERS/JRS/ALAT diagnostic guidelines for IPF based on usual interstitial pneumonia (UIP) patterns, the pooled κ value was 0.61 (95% CI: 0.48, 0.74). One study reported a κ value of 0.87 for ILD progression. Seven studies assessing ILD severity could not be pooled; the individual κ values for ILD severity ranged from 0.64 to 0.90, and ICC values ranged from 0.63 to 0.96. Conclusion There was moderate agreement between thoracic radiologists when assessing ILD features and UIP pattern diagnosis but little evidence on agreement of disease severity, extent, or progression. Meta-analysis registry no. PROSPERO CRD42022361803 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Humbert in this issue.

Assessment of quality of life in IPF Patients: a multicenter observational study.

This study aimed to examine how dyspnea, cough, sleep disruption, anxiety, depression, and physiological factors affect the quality of life in newly diagnosed, untreated IPF patients. This study is a multicenter observational study. Patients not receiving antifibrotic treatment were included. To assess patients' quality of life, Leicester Cough Questionnaire (LCQ), St. George's Respiratory Questionnaire (SGRQ), Short Form-36 (SF-36), Hospital Anxiety and Depression Scale (HADS), Borg Dyspnea Index (BDI), Modified Medical Research Council Dyspnea Scale (MMRC) score, Composite Physiological Index (CPI), Gender Age and physiology (GAP) score, and Pittsburgh Sleep Quality Index (PSQI) were administered. Among 88 patients (mean age: 67.6±8.5 years), 81.9% were diagnosed with IPF through HRCT, 14.8% through surgery, and 3.4% via cryobiopsy. The average disease duration was 2.2±2.9 years. Over 50% experienced moderate to severe depression, and 40% had moderate to severe anxiety. In the IPF group, 13.6% had possible usual interstitial pneumonia (UIP), and 81.8% had definite UIP pattern. No significant differences were found between UIP groups in various scores. Anxiety and depression correlated negatively with respiratory function and positively with MMRC score and BDI. Sleep quality scores had similar correlations. Patients with good sleep quality had better respiratory parameters (p=0.013), lower MMRC (p=0.004), BDI (p=0.026), and CPI (p=0.047). -Conclusion: A notable number of IPF patients in follow-up show symptoms of anxiety and depression. Moreover, declining respiratory function not only diminishes sleep quality but also elevates dyspnea scores.

Chemokine receptor CXCR4 based positron emission tomography imaging in systemic sclerosis-related interstitial lung disease.

To assess chemokine receptor CXCR4 expression in lung parenchyma and on peripheral immune cells in systemic sclerosis-related interstitial lung disease (SSc-ILD) patients. SSc-ILD patients underwent 68Ga- CPCR4 Trifluoroacetate positron emission tomography (PET) scan, SUVmean in different lung regions and architecturally abnormal areas, and receiver operating characteristic (ROC) curves were analyzed. CXCR4 expression on peripheral immune cells using flow cytometer was studied and correlated with the different lung regions. In addition, subset analysis of CXCR4 expression by clinical subset (early, progressive, stable), ILD pattern and anti-Scl-70 positivity were done. On PET, SSc-ILD patients showed higher median SUVmean uptake of CXCR4 in the whole lung (0.56; p< 0.0001), different lung regions and architecturally abnormal areas than controls. Highest area under curve (AUC) were observed in dorsobasal regions (AUC-0.91; p< 0.0001) and reticular with architecturally distorted areas (AUC-0.95; p< 0.0001). Progressive subset had higher whole lung median SUVmean (0.73) than early (0.49; p< 0.0001) and stable (0.45; p< 0.0001) subsets, and AUC than early and stable subsets. Usual interstitial pneumonia pattern ILD showed higher CXCR4 uptake compared with non-specific interstitial pneumonia (p= 0.0032). Additionally, a trend for higher uptake was noted in anti-Scl70 positive patients as compared with anti-Scl70 negative ones. SSc-ILD patients had higher CD4+CXCR4+T cells (p= 0.0003), and CD8+CXCR4+T cells (p= 0.0013), and showed moderate to strong association on correlation with the lung parenchymal regions. In SSc-ILD, CXCR4 expression is upregulated in both lung parenchyma and peripheral T cells, significantly in progressive and UIP subsets. CXCR4 expression is a potential tool for activity assessment and prognostication.

Durvalumab with etoposide and carboplatin for patients with extensive-stage small cell lung cancer and interstitial lung disease: A multicenter, open-label prospective trial

ObjectivesCertain guidelines recommend caution when administering immunotherapy in patients with pre-existing interstitial lung disease (ILD) owing to the high incidence of pneumonitis induced by anti-cancer therapy. A prospective clinical trial assessing the safety of chemoimmunotherapy in patients with small-cell lung cancer (SCLC) and pre-existing ILD is warranted. Therefore, this study evaluated the safety and efficacy of chemoimmunotherapy in patients with extensive-stage (ES)-SCLC and mild idiopathic interstitial pneumonia (IIP). MethodsIn this multicenter prospective trial, patients with ES-SCLC and pre-existing mild chronic fibrosing IIP were recruited. Mild IIP was defined as the exclusion of poor pulmonary function, a definite usual interstitial pneumonia (UIP) pattern, and positivity for autoantibodies in blood tests. The patients received durvalumab, etoposide, and carboplatin every three weeks (induction phase), followed by 1,500 mg durvalumab every four weeks (maintenance phase). The primary endpoint was severe pneumonitis-free rate. ResultsTwenty-one patients were included in the analysis. Among them, 13 patients displayed a probable UIP pattern, whereas eight patients exhibited an indeterminate for UIP pattern. Two patients (9.5 %) had pneumonitis of any grade during the induction phase; one had Grade 1 and the other had Grade 5 pneumonitis. No other patient developed pneumonitis during the maintenance phase. The severe pneumonitis-free rate was 95.2 % (95 % confidence interval (CI): 77.3–99.2 %). The median progression-free survival was 5.5 months (95 % CI: 3.6–6.4 months). Median overall survival was 10.7 months (95 % CI: 6.0 months to not reached). ConclusionsChemoimmunotherapy is a feasible treatment approach for patients with ES-SCLC and mild IIP.

Pathological features of connective tissue disease-associated interstitial lung disease in transbronchial cryobiopsies.

Transbronchial cryobiopsies are increasingly used for the diagnosis of interstitial lung disease (ILD), but there is a lack of published information on the features of specific ILD in cryobiopsies. Here we attempt to provide pathological guidelines for separating usual interstitial pneumonia (UIP) of idiopathic pulmonary fibrosis (IPF), fibrotic hypersensitivity pneumonitis (FHP) and connective tissue disease-associated ILD (CTD-ILD) in cryobiopsies. We examined 120 cryobiopsies from patients with multidisciplinary discussion (MDD)-established CTD-ILD and compared them to a prior series of 121 biopsies from patients with MDD-established IPF or FHP. A non-specific interstitial pneumonia (NSIP) pattern alone was seen in 36 of 120 (30%) CTD-ILD, three of 83 (3.6%) FHP and two of 38 (5.2%) IPF cases, statistically favouring a diagnosis of CTD-ILD. The combination of NSIP + OP was present in 29 of 120 (24%) CTD-ILD, two of 83 (2.4%) FHP and none of 38 (0%) IPF cases, favouring a diagnosis of CTD-ILD. A UIP pattern, defined as fibroblast foci plus any of patchy old fibrosis/fibrosis with architectural distortion/honeycombing, was identified in 28 of 120 (23%) CTD-ILD, 45 of 83 (54%) FHP and 27 of 38 (71%) IPF cases and supported a diagnosis of FHP or IPF. The number of lymphoid aggregates/mm2 and fibroblast foci/mm2 was not different in IPF, CTD-ILD or FHP cases with a UIP pattern. Interstitial giant cells supported a diagnosis of FHP or CTD-ILD over IPF, but were infrequent. In the correct clinical/radiological context the pathological findings of NSIP, and particularly NSIP plus OP, favour a diagnosis of CTD-ILD in a cryobiopsy, but CTD-ILD with a UIP pattern, FHP with a UIP pattern and IPF generally cannot be distinguished.

Idiopathic Pulmonary Fibrosis in Type 2 Diabetes Mellitus

Type 2 Diabetes Mellitus (T2DM) is a chronic condition that afflicts millions of people worldwide. T2DM correlates with increased levels of pro-inflammatory and pro-fibrotic molecules and respiratory cell injury leading to Idiopathic Pulmonary Fibrosis (IPF) development. Idiopathic pulmonary fibrosis patients with T2DM have a higher rate of progression and worse prognosis, including higher hospital stay length and mortality rate. On High-resolution Computed Tomography (HRCT), IPF patients with T2DM are more likely to exhibit the Usual Interstitial Pneumonia (UIP) pattern (reticular and honeycomb patterns) than those without T2DM. Interventions for IPF include non-pharmacological interventions, i.e., oxygen supplementation and pulmonary rehabilitation, and pharmacological interventions, including nintedanib and pirfenidone. Antidiabetic agents, such as metformin, thiazolidinediones, and glucagon-like peptide 1, have shown anti-pulmonary fibrotic effects and to be associated with better clinical outcomes.

Computed Tomography Spectrum of Complications in Usual Interstitial Pneumonia Pattern in a Tertiary Care Hospital: A Descriptive Cross- sectional Study.

Idiopathic pulmonary fibrosis is the most prevalent form of interstitial lung disease, which presents as usual interstitial pneumonia on histopathology and imaging. It leads to significant lung scarring, damage, and fibrosis and is associated with a high degree of mortality, repeated hospital admissions, and oxygen dependence. Many complications are associated with idiopathic pulmonary fibrosis, which further increases the morbidity of patients. High-resolution computed tomography chest is the imaging modality of choice for usual interstitial pneumonia tracking its progression, evaluating treatment response, and detecting potential complications. This descriptive cross-sectional study was approved by the Institutional Ethics Committee (Reference number: IEC-INT/2023/Study-1256). Departmental computed tomography report database from November, 2017 to June, 2018 was reviewed and scans with imaging features consistent with the 'usual interstitial pneumonia' pattern were identified. Total sampling method was used and two independent radiologists, blinded to the patient's clinical information, reviewed the high-resolution computed tomography chest scans to assess for imaging features of usual interstitial pneumonia and associated complications. Data was collected and analyzed using Microsoft Excel. There were 65 patients reported as unusual interstitial pneumonia pattern. Emphysema and pneumothorax were identified in 4 (6.15%) and 1 (1.53%) scans, respectively. Two (3.08%) scans showed features of pulmonary arterial hypertension. Ten (15.38%) scans exhibited findings consistent with co-existent or superimposed pulmonary infection. Additionally, features of lung malignancy were identified in high-resolution computed tomography scans of 5 (7.69%) patients. Patients with UIP often experience severe lung scarring, and frequent complications, and require regular chest CT scans to monitor disease progression and identify potential complications.

Risk factors of mortality in patients with rheumatoid arthritis-associated interstitial lung disease: a single-centre prospective cohort study

ObjectivesTo determine the risk factors for mortality in Korean patients with rheumatoid arthritis (RA)-associated interstitial lung disease (ILD) in comparison to patients with RA but without ILD (RA-nonILD).MethodsData were extracted from a single-centre prospective cohort of RA patients with a chest computed tomography scan at an academic referral hospital in Korea. Patients with RA-ILD enroled between May 2017 and August 2022 were selected, and those without ILD were selected as comparators. The mortality rate was calculated, and the causes of each death were investigated. We used Cox proportional hazard regression with Firth’s penalised likelihood method to identify the risk factors for mortality in patients with RA-ILD.ResultsA total of 615 RA patients were included: 200 with ILD and 415 without ILD. In the RA-ILD group, there were 15 deaths over 540.1 person-years (PYs), resulting in mortality rate of 2.78/100 PYs. No deaths were reported in the RA-nonILD group during the 1669.9 PYs. The primary causes of death were infection (nine cases) and lung cancer (five cases), with only one death attributed to ILD aggravation. High RA activity (adjusted HR 1.87, CI 1.16–3.10), baseline diffusing capacity for carbon monoxide (DLCO) < 60% (adjusted HR 4.88, 95% CI 1.11–45.94), and usual interstitial pneumonia (UIP) pattern (adjusted HR 5.13, 95% CI 1.00–57.36) were identified as risk factors for mortality in RA-ILD patients.ConclusionPatients with RA-ILD have an elevated risk of mortality compared with those without ILD. Infection-related deaths are the main causes of mortality in this population. High RA activity, low DLCO, and the UIP pattern are significantly associated with the mortality in patients with RA-ILD.

Relationship between nailfold capillaroscopy findings and the etiology and prognosis of interstitial lung disease

ObjectivesConnective tissue-associated interstitial lung diseases (CTD-ILD) are believed to be caused by microvascular damage. The objective of this study was to assess the nailfold capillaroscopy (NFC) pattern in patients diagnosed with both CTD-ILD and non-CTD-ILD to identify microvascular changes and determine the relation between capillaroscopic parameters, clinical variables, and disease-related measurements.Patients and methodsThis cross-sectional study included 95 patients with interstitial lung disease who applied to our Rheumatology and Chest Clinics between September 2021 and July 2023. The patients were divided into two groups based on their diagnosis: non-CTD-ILD (group 1) and CTD-ILD (group 2). Nailfold capillaroscopy was performed.ResultsNinety-five patients, 49 (51% female, mean age 62.31 ± 11.027 years) in group 1 and 46 (69.6% female, mean age 62.09 ± 10.887 years) in group 2, were included in the study. Abnormal capillary morphologies were both detected in the CTD-ILD group and the non-CTD-ILD groups. In patients with a usual interstitial pneumonia (UIP) pattern on chest computed tomography (CT), tortuosity was higher than in patients with non-specific interstitial pneumonia (NSIP) (P = 0.041), and the proportion of tortuosity increased significantly as the duration of the disease increased (P = 0.016).ConclusionOur study highlights capillaroscopic abnormalities alone may not be sufficient to differentiate CTD-ILD (other than systemic sclerosis) from non-CTD-ILD. The presence of NFC abnormalities in non-CTD-ILD may suggest that fibrotic lung disease could potentially play a role in the deterioration of the microvascular structure or abnormal angiogenesis. Our study demonstrated that a multidisciplinary approach, incorporating clinical, morphological, pathological, and serological evaluations, is necessary for interpreting ILD.Key Points• Capillaroscopic abnormalities can also be seen in non-CTD-ILD.• Capillaroscopy findings do not distinguish the non-Ssc etiology of ILD.• Nailfold capillaroscopy may have the potential to serve as a useful tool in predicting prognosis and monitoring the disease progression in patients with idiopathic pulmonary fibrosis (IPF).

Stress–strain curve and elastic behavior of the fibrotic lung with usual interstitial pneumonia pattern during protective mechanical ventilation

Patients with acute exacerbation of lung fibrosis with usual interstitial pneumonia (EUIP) pattern are at increased risk for ventilator-induced lung injury (VILI) and mortality when exposed to mechanical ventilation (MV). Yet, lack of a mechanical model describing UIP-lung deformation during MV represents a research gap. Aim of this study was to develop a constitutive mathematical model for UIP-lung deformation during lung protective MV based on the stress–strain behavior and the specific elastance of patients with EUIP as compared to that of acute respiratory distress syndrome (ARDS) and healthy lung. Partitioned lung and chest wall mechanics were assessed for patients with EUIP and primary ARDS (1:1 matched based on body mass index and PaO2/FiO2 ratio) during a PEEP trial performed within 24 h from intubation. Patient’s stress–strain curve and the lung specific elastance were computed and compared with those of healthy lungs, derived from literature. Respiratory mechanics were used to fit a novel mathematical model of the lung describing mechanical-inflation-induced lung parenchyma deformation, differentiating the contributions of elastin and collagen, the main components of lung extracellular matrix. Five patients with EUIP and 5 matched with primary ARDS were included and analyzed. Global strain was not different at low PEEP between the groups. Overall specific elastance was significantly higher in EUIP as compared to ARDS (28.9 [22.8–33.2] cmH2O versus 11.4 [10.3–14.6] cmH2O, respectively). Compared to ARDS and healthy lung, the stress/strain curve of EUIP showed a steeper increase, crossing the VILI threshold stress risk for strain values greater than 0.55. The contribution of elastin was prevalent at lower strains, while the contribution of collagen was prevalent at large strains. The stress/strain curve for collagen showed an upward shift passing from ARDS and healthy lungs to EUIP lungs. During MV, patients with EUIP showed different respiratory mechanics, stress–strain curve and specific elastance as compared to ARDS patients and healthy subjects and may experience VILI even when protective MV is applied. According to our mathematical model of lung deformation during mechanical inflation, the elastic response of UIP-lung is peculiar and different from ARDS. Our data suggest that patients with EUIP experience VILI with ventilatory setting that are lung-protective for patients with ARDS.

Central Role of CT in Management of Pulmonary Fibrosis.

With the approval of antifibrotic medications to treat patients with idiopathic pulmonary fibrosis and progressive pulmonary fibrosis, radiologists have an integral role in diagnosing these entities and guiding treatment decisions. CT features of early pulmonary fibrosis include irregular thickening of interlobular septa, pleura, and intralobular linear structures, with subsequent progression to reticular abnormality, traction bronchiectasis or bronchiolectasis, and honeycombing. CT patterns of fibrotic lung disease can often be reliably classified on the basis of the CT features and distribution of the condition. Accurate identification of usual interstitial pneumonia (UIP) or probable UIP patterns by radiologists can obviate the need for a tissue sample-based diagnosis. Other entities that can appear as a UIP pattern must be excluded in multidisciplinary discussion before a diagnosis of idiopathic pulmonary fibrosis is made. Although the imaging findings of nonspecific interstitial pneumonia and fibrotic hypersensitivity pneumonitis can overlap with those of a radiologic UIP pattern, these entities can often be distinguished by paying careful attention to the radiologic signs. Diagnostic challenges may include misdiagnosis of fibrotic lung disease due to pitfalls such as airspace enlargement with fibrosis, paraseptal emphysema, recurrent aspiration, and postinfectious fibrosis. The radiologist also plays an important role in identifying complications of pulmonary fibrosis-pulmonary hypertension, acute exacerbation, infection, and lung cancer in particular. In cases in which there is uncertainty regarding the clinical and radiologic diagnoses, surgical biopsy is recommended, and a multidisciplinary discussion among clinicians, radiologists, and pathologists can be used to address diagnosis and management strategies. This review is intended to help radiologists diagnose and manage pulmonary fibrosis more accurately, ultimately aiding in the clinical management of affected patients. ©RSNA, 2024 Supplemental material is available for this article.

Radiofrequency Ablation in Patients with Interstitial Lung Disease and Lung Neoplasm: A Retrospective Multicenter Study

PurposeTo retrospectively investigate the safety and effectiveness of percutaneous radiofrequency (RF) ablation by analyzing results in patients with lung neoplasm accompanied by interstitial lung disease (ILD) on computed tomography (CT) in a multicenter study. Materials and MethodsPatients with lung neoplasm accompanied by ILD who underwent RF ablation between April 2002 and October 2017 at 7 institutions were investigated. Technical success rate and local tumor progression (LTP) of ablated tumors were evaluated. Adverse events including acute exacerbation of ILD were also evaluated. Univariate analyses were performed to identify factors associated with acute exacerbation. ResultsForty-nine patients with 64 lung neoplasms (mean diameter, 23 mm; range, 4–58 mm) treated in 66 sessions were included. Usual interstitial pneumonia (UIP) pattern on CT was identified in 23 patients (47%). All patients underwent successful RF ablation. Acute exacerbations were seen in 5 sessions (8%, 7% with UIP pattern and 8% without) in 5 patients, all occurring on or after 8 days (median, 12 days; range, 8–30 days). Three of those 5 patients died of acute exacerbation. Treatment resulted in mortality after 5% of sessions, representing 6% of patients. Pleural effusion and fever (temperature ≥ 38°C) after RF ablation were identified by univariate analysis (P = .001 and P = .02, respectively) as significant risk factors for acute exacerbation. The cumulative LTP rate was 43% at 1 year. ConclusionsRF ablation appears feasible for patients with lung neoplasm complicated by ILD. Acute exacerbation occurred in 8% of patients with symptoms occurring more than 8 days after ablation and was associated with a 45% mortality rate.

Antifibrotics in the Management of Rheumatoid Arthritis-Associated Interstitial Lung Disease: Prospective Real-World Experience From an Interstitial Lung Disease Clinic in India.

Interstitial lung disease (ILD) in rheumatoid arthritis (RA) is a serious complication with varied prevalence ranging from 4% to as high as 68%, with varied presentation. Immunosuppressants and antifibrotics are used in the management of RA ILD. The clinicodemographic profile and presentation in our country need to be further explored. We assessed the efficacy and safety profile of antifibrotic drugs in combination with immunosuppressants among RA ILD patients. A prospective observational study was conducted in the Interstitial Lung Disease (ILD) Clinic in the Department of Pulmonary Medicine, All India Institute of Medical Sciences Raipur, India, between January 2022 to January 2023. RA patients with dyspnea and chronic cough were referred to us for evaluation of ILD. Patients underwent clinical examination, complete lung function study including spirometry, single breath diffusion capacity for carbon monoxide (DLCO), six-minute walk test, and high-resolution computed tomography of the thorax. Quality of life was assessed using the King's Brief Interstitial Lung Disease (KBILD) questionnaire. Two hundred eighteen RA patients were evaluated and out of these, 43 (20.8%) had features of ILD on high-resolution computed tomogram (HRCT) thorax. Twenty-six (2.18%) met the inclusion criteria for starting antifibrotics. The mean ± SD. age of the patients was 52.96 ± 14.04 and the majority (77%) were females. Fourteen (53.38%) patients had usual interstitial pneumonia (UIP)/probable UIP pattern and 12 (46.22%) had nonspecific interstitial pneumonia (NSIP) patterns on HRCT. Out of 26 patients, 24 (92.3%) were started on antifibrotics. Fourteen (53.8%) patients were on nintedanib and 10 (38.4%) were on pirfenidone. The mean ± SD forced vital capacity (FVC)% predictedwas 62.5 ± 20.04.The mean ± SD. The DLCO percentage predicted was 54.4 ± 22.8. Twenty-two (84.6%) patients did not experience any side effects. The mean ± SD. KBILD score was 59.9 ± 11.17 and was similar in both sexes. In our study, the prevalence of RA ILD was nearly 20.8% and more common in females. Twenty-four (2%) patients were included for antifibrotic treatment. There was an improvement in lung function at the end of six months, but the change was not significant. All patients tolerated antifibrotics well without any serious adverse events.

Risk Factors and Biomarkers for Interstitial Lung Disease and Pulmonary Arterial Hypertension in Systemic Sclerosis: Experience of Two Tertiary Centers in Turkey

Purpose: To define the clinical and laboratory characteristics of patients with systemic sclerosis (SSc), and to investigate the risk factors affecting the prevalence of interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH), which are important causes of morbidity and mortality. Patients and methods: 88 patients with SSc were compared according to the presence of ILD and PAH. ILD was confirmed by chest computed tomography, and PAH was suspected and considered probable PAH when right ventricular systolic pressure was &gt;40 mmHg according to echocardiography. Results: Of the 88 patients, 44.3% had diffuse-type and 55.7% had limited-type SSc. Diffuse type, percentages of positive anti-scleroderma-70 (anti-Scl70) antibody and anti-centromere antibody, white blood cell (WBC), platelet, erythrocyte sedimentation rate (ESR), smoking, and presence of the sclerodactyly and telangiectasia differed significantly in SSc with ILD group. The positive titer of anti-Scl70 antibody (odds ratio (OR)=6.124, p=0.004), platelet count (OR=0.138, p=0.002), ESR (OR=1.042, p=0.035) and presence of telangiectasia (OR=10.571, p=0.001) were associated with ILD in patients with SSc. Also, while diffuse-type (OR=0.223, p=0.010), the presence of sclerodactyly (OR=11.112, p=0.028) and telangiectasia (OR=3.861, p=0.020) were risk factors for the development of ILD in nonspecific interstitial pneumonia pattern, anti-Scl-70 antibody positivity (OR=12.921, p=0.019) and high ESR (OR=1.034, p=0.030) were found to be risk factors for the development of usual interstitial pneumonia pattern. Conclusion: Positive titer of the anti-Scl70 antibody, diffuse type, presence of telangiectasia, and high ESR were independently associated with ILD in SSc patients.

#1356 Kidney phenotype in interstitial lung disease associated with ANCA-vasculitis: European Multicentre Study

Abstract Background and Aims Interstitial lung disease (ILD) in ANCA-associated vasculitis (AAV) has the appearance of a progressive fibrotic disease on imaging and primarily affects the interstitial lung compartment and is usually associated with MPO-ANCA. Whether patients with AAV-ILD display a similar fibrotic pattern in their kidneys is unclear. Method A European multicentre retrospective study included patients with AAV-ILD. The diagnosis of ILD was confirmed by a CT chest pattern of usual interstitial pneumonia (UIP), non-specific interstitial pneumonia (NSIP), organising pneumonia or chronic hypersensitivity pneumonia. We aimed to determine if kidney involvement in AAV-ILD exhibited a more fibrotic pattern compared to AAV-related nephritis without ILD, using data from the Cambridge AAV cohort. Results 135 patients with AAV-ILD were included; 94 (70%) had also kidney involvement, in whom the mean age was 71 ± 11 years and 87% MPO-ANCA positive. The ILD diagnosis preceded AAV in 17%, 64% presented concurrently with kidney involvement, 20% with pulmonary haemorrhage. The most common lung radiological pattern was UIP (67%). At presentation, the median glomerular filtration rate (GFR) was 27 ml/min per 1.73 m2 (interquartile range 12-50), with a median albumin-to creatinine ratio 23 mg/mmol (IQR 10-97). Among 72 patients with available kidney biopsy, the most prevalent Berden class was focal in 45%, followed by mixed in 33%, crescentic in 18% and sclerotic in 4%. Although, the prevalence of Berden classes did not significantly differ between ILD-nephritis and no ILD-nephritis groups, the former group had a higher baseline GFR (p = 0.05), lower albuminuria level (p = 0.002), higher percentage of normal glomeruli (p = 0.027), lower glomerular necrosis percentage (p = 0.002) and higher interstitial fibrosis score (p = 0.049). Within five years, the ILD-nephritis group demonstrated renal recovery, as indicated by an adjusted mean delta GFR of 13.4 ml/min per 1.73 m2, without a significant difference compared to the no ILD-nephritis group. Over a median follow-up of 4.9 years (IQR 2-9), the progression to end-stage kidney disease (ESKD) was comparable between the groups. However, notably, the ILD-nephritis group experienced significantly poorer survival rates (mean 10.9 years vs 17.9 years, log-rank p &amp;lt; 0.001). Conclusion In AAV-ILD, kidney involvement is often characterized by fewer inflammatory and a higher prevalence of fibrotic lesions than on non-ILD-AAV. Despite initial differences in renal pathology and kidney function between these groups, both demonstrated similar risks of progressing to ESKD. Nevertheless, it's crucial to underscore the significant influence of ILD on the overall outcomes of AAV patients with kidney involvement.

Patrones radiológicos en enfermedades pulmonares intersticiales

This article explores the role of high-resolution computed tomography (HRCT) in the diagnosis of diffuse interstitial lung diseases (ILD), discussing key tomographic findings, parenchymal changes, and the importance of identifying various radiological patterns, with a special focus on the usual interstitial pneumonia (UIP) pattern. Given the complexity and diversity of manifestations of diffuse ILD, the collaborative evaluation of a multidisciplinary team, in which the radiologist plays a fundamental role in the diagnostic chain using HRCT, is essential. This exam enables the detection of parenchymal alterations in DILD, such as ground-glass opacities, consolidation, reticular patterns, traction bronchiectasis/bronchiectasis, and honeycombing. The interpretation and association of these findings, along with their distribution, facilitate the establishment of specific radiological patterns that, in addition to indicating possible etiologies, guide the most appropriate therapeutic options. The adoption of specific imaging protocols and the use of standardized language are essential to increase diagnostic accuracy. Moreover, the incorporation of technological innovations, such as advanced photon counting technology and automated analysis through artificial intelligence, promise to significantly improve the identification and quantification of interstitial alterations, shaping the future of thoracic radiology.