Computed tomography findings in acute exacerbation of idiopathic pulmonary fibrosis

HRCT findings predict 1-year mortality in patients with acute exacerbation of idiopathic inflammatory myopathies-associated interstitial lung disease

Background

Acute exacerbation of idiopathic inflammatory myopathies-associated interstitial lung disease (AE-IIM-ILD) is a significant event associated with increased morbidity and mortality. However, few studies investigated the potential prognostic factors contributing to mortality in patients who experience AE-IIM-ILD.

Objectives

The purpose of our study was to comprehensively investigate whether high-resolution computed tomography (HRCT) findings predict the 1-year mortality in patients who experience AE-IIM-ILD.

Methods

A cohort of 69 patients with AE-IIM-ILD was retrospectively created. The cohort was 79.7 % female, with a mean age of 50.7. Several HRCT features, including total interstitial lung disease extent (TIDE), distribution patterns, and radiologic ILD patterns, were assessed. A directed acyclic graph (DAG) was used to evaluate the statistical relationship between variables. The Cox regression method was performed to identify potential prognostic factors associated with mortality.

Results

The HRCT findings significantly associated with AE-IIM-ILD mortality include TIDE (HR per 10%-increase, 1.64; 95%CI, 1.29-2.1, p < 0.001; model 1: C-index, 0.785), diffuse distribution pattern (HR, 3.75, 95%CI, 1.5-9.38, p = 0.005; model 2: C-index, 0.737), and radiologic diffuse alveolar damage (DAD) pattern (HR, 6.37, 95 % CI, 0.81-50.21, p = 0.079; model 3: C-index, 0.735). TIDE greater than 58.33 %, diffuse distribution pattern, and radiologic DAD pattern correlate with poor prognosis. The 90-day, 180-day, and 1-year survival rates of patients who experience AE-IIM-ILD were 75.3 %, 66.3 %, and 63.3 %, respectively.

Conclusion

HRCT findings, including TIDE, distribution pattern, and radiological pattern, are predictive of 1-year mortality in patients who experience AE-IIM-ILD.

Complications of fibrotic interstitial lung disease for the general radiologist

Interstitial lung diseases (ILDs) are a heterogeneous group of conditions characterised by non-infective inflammation and scarring of the lung parenchyma. They are not infrequently encountered by the general radiologist in both acute and outpatient reporting settings who may even be the first to make the diagnosis. In the acute setting, patients with ILD can present with respiratory deterioration due to a number of causes and in addition to the common causes of dyspnoea, an acute exacerbation of ILD needs to be considered. An exacerbation can be initiated by common triggers such as infection, pulmonary embolism (PE), and heart failure, and it can also be initiated by an insult to the lung or occur due to an unknown cause. Particular care needs to be taken when interpreting computed tomography (CT) examinations in these patients as the findings of an acute exacerbation are non-specific and patient and technical factors can cause spurious appearances including dependent changes, breathing artefact and contrast medium opacification. In the non-acute setting, patients with ILD are at increased risk of lung cancer and pulmonary hypertension (PH), with lung cancer being a particularly important consideration as treatments carry the risk of triggering an acute exacerbation or deterioration in lung function. Overall, this review aims to provide an overview for the general radiologist of additional factors to consider when interpreting scans in patients with ILD and how the presence of ILD impacts the differential diagnoses and complications that can occur in these patients in both acute and non-acute settings.

Relationship between idiopathic interstitial pneumonias (IIPs) and connective tissue disease-related interstitial lung disease (CTD-ILD): A narrative review

While idiopathic interstitial pneumonia (IIP) centering on idiopathic pulmonary fibrosis (IPF) is the most prevalent interstitial lung disease (ILD), especially in the older adult population, connective tissue disease (CTD)-related ILD is the second most prevalent ILD. The pathogenesis of IPF is primarily fibrosis, whereas that of other ILDs, particularly CTD-ILD, is mainly inflammation. Therefore, a precise diagnosis is crucial for selecting appropriate treatments, such as antifibrotic or immunosuppressive agents. In addition, some patients with IIP have CTD-related features, such as arthritis and skin eruption, but do not meet the criteria for any CTD, this is referred to as interstitial pneumonia with autoimmune features (IPAF). IPAF is closely associated with idiopathic nonspecific interstitial pneumonia (iNSIP) and cryptogenic organizing pneumonia (COP). Furthermore, patients with iNSIP or those with NSIP with OP overlap frequently develop polymyositis/dermatomyositis after the diagnosis of IIP. Acute exacerbation of ILD, the most common cause of death, occurs more frequently in patients with IPF than in those with other ILDs. Although acute exacerbation of CTD-ILD occurs at a low rate of incidence, patients with rheumatoid arthritis, microscopic polyangiitis, or systemic sclerosis experience more acute exacerbation of CTD-ILD than those with other CTD. In this review, the features of each IIP, focusing on CTD-related signatures, are summarized, and the pathogenesis and appropriate treatments to improve the prognoses of patients with various ILDs are discussed.

Pulse versus non-pulse corticosteroid therapy in patients with acute exacerbation of idiopathic pulmonary fibrosis

BACKGROUND AND OBJECTIVE

Corticosteroids are commonly used for the treatment of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF); however, the optimal initial dose of corticosteroids remains uncertain due to a lack of sufficient evidence. We evaluated whether the administration of a pulse dose of corticosteroids resulted in improved survival outcomes compared with conventional non-pulse dose of corticosteroids.

METHODS

We retrospectively analysed 238 patients with AE-IPF treated with corticosteroids at a tertiary referral hospital between January 2013 and December 2021. Based on whether a pulse dose of corticosteroids (methylprednisolone of ≥250 mg/day or equivalent) was administered within 7 days of hospitalization for AE-IPF, the patients were divided into the pulse and non-pulse regimen groups. The survival outcomes were compared between the two groups using multivariable regression and propensity score-matched analyses.

RESULTS

Among the 238 patients, 59 patients received pulse dose of corticosteroids, whereas 179 patients received conventional non-pulse dose of corticosteroids. After adjusting for the confounding factors related to the baseline clinical and radiographic severity, compared with the conventional non-pulse regimen, the pulse regimen of corticosteroids did not reduce the risk of mortality at the 3-month (aHR 0.84, 95% CI 0.45-1.38) or 12-month (aHR 0.96, 95% CI 0.60-1.25) follow-ups. Propensity score-matched analysis revealed similar results.

CONCLUSION

The survival outcomes of patients with AE-IPF who received a pulse dose of corticosteroids did not differ from those of patients who received conventional non-pulse dose of corticosteroids. Further prospective studies are required to establish the optimal initial dose of corticosteroids for the treatment of AE-IPF.

Prognostic factors associated with mortality in acute exacerbations of idiopathic pulmonary fibrosis: A systematic review and meta-analysis

BACKGROUND

Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) increases mortality risk, but which factors increase mortality is unknown. We aimed to perform a prognostic review of factors associated with mortality in patients with IPF.

STUDY DESIGN

and methods: We searched MEDLINE, EMBASE, and CINAHL for studies that reported on the association between any prognostic factor and AE-IPF. We assessed risk of bias using the QUIPS tool. We conduced pairwise meta-analyses using REML heterogeneity estimator, and GRADE approach to assess the certainty of the evidence.

RESULTS

We included 35 studies in our analysis. We found that long-term supplemental oxygen at baseline (aHR 2.52 [95 % CI 1.68 to 3.80]; moderate certainty) and a diagnosis of IPF compared to non-IPF ILD (aHR 2.19 [95 % CI 1.22 to 3.92]; moderate certainty) is associated with a higher risk of death in patients with AE-IPF. A diffuse pattern on high resolution computed tomography (HRCT) compared to a non-diffuse pattern (aHR 2.61 [95 % CI 1.32 to 2.90]; moderate certainty) is associated with a higher risk of death in patients with AE-IPF. We found that using corticosteroids prior to hospital admission (aHR 2.19 [95 % CI 1.26 to 3.82]; moderate certainty) and those with increased neutrophils (by % increase) in bronchoalveolar lavage (BAL) during the exacerbation is associated with a higher risk of death (aHR 1.02 [1.01 to 1.04]; moderate certainty).

INTERPRETATION

Our results have implications for healthcare providers in making treatment decisions and prognosticating the clinical trajectory of patients, for researchers to design future interventions to improve patient trajectory, and for guideline developers in making decisions about resource allocation.

Impact of partial pressure of arterial oxygen and radiologic findings on postoperative acute exacerbation of idiopathic interstitial pneumonia in patients with lung cancer

PURPOSE

To establish accurate diagnostic criteria and predictors of treatment response for postoperative acute exacerbation (AE) in patients with lung cancer and idiopathic interstitial pneumonia (IIP).

METHODS

Among 93 patients with IIP who underwent surgery for lung cancer, suspected postoperative AE developed in 20 (21.5%). Patients were divided into a progressive AE group, comprising patients with bilateral alveolar opacities and decreasing PaO2 ≥ 10 mmHg (n = 5); an incipient AE group, comprising patients with unilateral alveolar opacities and decreasing PaO2 ≥ 10 mmHg (n = 10); and an indeterminate AE group, comprising patients with alveolar opacities but decreasing PaO2 < 10 mmHg (n = 5).

RESULTS

The progressive AE group had significantly higher 90-day mortality (80%) than the incipient AE group (10%, P = 0.017) or the indeterminate AE group (0%, P = 0.048). Bilateral opacities may indicate advanced AE and poor prognosis, whereas unilateral opacities may indicate an early stage of AE and a good prognosis. PaO2 < 10 mmHg may indicate conditions other than AE.

CONCLUSIONS

In patients with lung cancer and IIP, decreasing PaO2 and HRCT findings may allow for the initiation of rapid and accurate treatment strategies for postoperative AE.

FDG-Avid Granulomatous Lymphocytic Interstitial Lung Disease With Common Variable Immunodeficiency

ABSTRACT

A 26-year-old woman with known common variable immunodeficiency was referred for FDG PET/CT because of interstitial pulmonary abnormalities and enlarged mediastinal and hilar lymph nodes. FDG PET showed a combination of ground-glass abnormalities and pulmonary nodules, both displaying increased FDG uptake. In addition, multiple FDG-avid axillary, mediastinal, hilar, and inguinal lymph nodes were found. The abnormalities were diagnosed as granulomatous-lymphocytic interstitial lung disease. Cytology of mediastinal lymph nodes yielded only benign disease, without further specification, whereas histology of an excised axillary lymph node showed reactive changes, but no malignancy.

Imaging Features of Idiopathic Interstitial Lung Diseases

Idiopathic interstitial pneumonias (IIPs) are a group of diffuse parenchymal lung diseases of unclear etiology and are distinguished from diffuse parenchymal lung diseases of known cause, such as connective tissue disease-related interstitial lung diseases or hypersensitivity pneumonitis by history, physical exam, imaging, serologic testing, and, when necessary, histopathology. The 2013 American Thoracic Society (ATS)/European Respiratory Society (ERS) guidelines are the most widely accepted classification of IIPs and include the following diagnoses: idiopathic pulmonary fibrosis, idiopathic nonspecific interstitial pneumonia, cryptogenic organizing pneumonia, acute interstitial pneumonia, idiopathic lymphocytic interstitial pneumonia, idiopathic pleuro-parenchymal fibroelastosis, respiratory bronchiolitis-interstitial lung disease, and desquamative interstitial pneumonia. The gold standard for diagnosis of IIP involves multidisciplinary discussion among pulmonologists, radiologists, and pathologists. The focus of this review will be to discuss the imaging features of the most common IIPs and the role of multidisciplinary discussion as the gold standard for diagnosis.

Nintedanib administration after the onset of acute exacerbation of interstitial lung disease in the real world

Nintedanib reduces the decline in forced vital capacity and extends the time to the first acute exacerbation of interstitial lung disease (AE-ILD). However, the effect of additional nintedanib administration after AE-ILD onset is unknown. This study aimed to investigate the efficacy and safety of nintedanib administration after AE-ILD development. We retrospectively collected the data of 33 patients who developed AE-ILD between April 2014 and January 2022. Eleven patients who received nintedanib after AE-ILD development and the remaining who did not were classified into the N and No-N groups, respectively. The survival time in the N group tended to be longer than that in the No-N group. The generalized Wilcoxson test revealed that the cumulative mortality at 90 days from AE-ILD onset was significantly lower in the N group. The time to subsequent AE-ILD development was significantly longer in the N group than that in the No-N group. The incidence of adverse gastrointestinal effects and liver dysfunction in the N group was 9-18%. Treatment without nintedanib after AE-ILD development and the ratio of arterial oxygen partial pressure to fractional inspired oxygen were significant independent prognostic factors in the multivariate analysis. Thus, nintedanib administration may be a treatment option for AE-ILD.

Acute exacerbation of interstitial lung disease in the intensive care unit: Principles of diagnostic evaluation and management

Interstitial lung disease (ILD) is typically managed on an outpatient basis. Critical care physicians manage patients with ILD in the setting of an acute exacerbation (ILD flare) causing severe hypoxia. The principles of management of acute exacerbation of ILD are different from those used to manage patients with acute respiratory distress syndrome from sepsis, etc. Selected patients may be candidates for aggressive measures like extracorporeal membrane oxygenation and lung transplantation, while almost all patients will benefit from early palliative care. This review focused on the types of ILD, diagnosis, and management pathways for this challenging condition.

Prognostic value of the qSOFA in patients with acute exacerbation of idiopathic pulmonary fibrosis

BACKGROUND

Patients with idiopathic pulmonary fibrosis (IPF) have a slowly progressive clinical course, although some develop acute exacerbations (AEs). An easily obtained composite score is desirable for predicting the survival rate in patients with AE of IPF (AE-IPF). We investigated the quick sequential organ failure assessment (qSOFA), originally developed to identify sepsis, as a predictor of mortality in patients with AE-IPF and compared it to other composite assessments.

METHODS

Consecutive patients with IPF admitted for their first AE between 2008 and 2019 were recruited retrospectively. The association between the qSOFA score obtained at admission and mortality was investigated.

RESULTS

During the study period, 97 patients with AE-IPF were hospitalized. The hospital mortality was 30.9%. Multivariate logistic regression analysis revealed that both the qSOFA and the Japanese Association for Acute Medicine (JAAM)-disseminated intravascular coagulation (DIC) scores were significant predictors of hospital mortality (odds ratio [OR] 3.86, 95% confidence interval [CI] 1.43-10.3; p = 0.007 and OR 2.71, 95% CI 1.56-4.67; p = 0.0004; respectively). Kaplan-Meier survival curves showed that both scores were consistently associated with survival. Furthermore, the sum of the two scores was a more effective predictor than the individual scores.

CONCLUSIONS

The qSOFA score of patients admitted with AE-IPF was associated with both in-hospital and long-term mortality, which was also true for the JAAM-DIC score. The qSOFA score plus the JAAM-DIC score should be determined during the diagnostic evaluation of a patient with AE-IPF. Both scores combined may be more effective at predicting outcomes than individual scores.

Combination of computed tomography imaging pattern and severity of respiratory failure as factors associated with prognosis for acute exacerbation of idiopathic chronic fibrosing interstitial pneumonia

BACKGROUND AND OBJECTIVES

The prognosis of idiopathic chronic fibrotic interstitial pneumonitis (CFIP) in patients with acute exacerbation (AE) is variable. We examined whether the imaging pattern on thoracic computed tomography (CT) or the severity of respiratory failure with AE-CFIP is associated with short-term prognosis.

METHODS

Patients admitted to two university hospitals were retrospectively analyzed and divided into derivation and validation cohorts. The distribution of newly appearing parenchymal abnormalities on thoracic CT was classified into peripheral, multifocal, and diffuse patterns. Respiratory failure was defined as severe if a fraction of inspired oxygen ≥ 0.5 was required to maintain percutaneous oxygen saturation ≥ 90% on admission. Factors associated with 90 day-mortality were analyzed using univariate and Cox proportional hazard regression.

RESULTS

In 59 patients with AE-CFIP of the derivation cohort, diffuse pattern on CT was associated with higher mortality within 90 days (43%) than peripheral/multifocal pattern (17%, p = 0.03). Additionally, compared with non-severe failure, severe respiratory failure was associated with higher mortality (47% vs. 21%, p = 0.06). Cox proportional hazard regression analysis demonstrated that a combination of diffuse pattern on CT and severe respiratory failure was associated with the poorest prognosis (hazard ratio [HR] 3.51 [interquartile range 1.26-9.80], p = 0.016) in the derivation cohort, which was confirmed in the validation cohort (n = 31, HR 4.30 [interquartile range 1.51-12.2], p = 0.006).

CONCLUSION

The combination of imaging pattern on thoracic CT and severity of respiratory failure was associated with the prognosis of idiopathic AE-CFIP.

Idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is the most common fibrosing lung disease. It is associated with a very poor prognosis. Treatments can delay the progression of IPF, so early diagnosis is fundamental. Radiologists play a fundamental role in the evaluation and accurate diagnosis of IPF. Identifying the characteristic patterns of IPF on high-resolution computed tomography (HRCT) is key in the process of multidisciplinary diagnosis, often obviating the need for surgical lung biopsies. This review describes and illustrates the clinical and imaging findings in IPF in the context of the most recent international guidelines, as well as the differential diagnosis and the role of HRCT in follow-up and assessment of complications.

Pathological Roles of Pulmonary Cells in Acute Lung Injury: Lessons from Clinical Practice

Interstitial lung diseases (ILD) are relatively rare and sometimes become life threatening. In particular, rapidly progressive ILD, which frequently presents as acute lung injury (ALI) on lung histopathology, shows poor prognosis if proper and immediate treatments are not initiated. These devastating conditions include acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF), clinically amyopathic dermatomyositis (CADM), epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI)-induced lung injury, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection named coronavirus disease 2019 (COVID-19). In this review, clinical information, physical findings, laboratory examinations, and findings on lung high-resolution computed tomography and lung histopathology are presented, focusing on majorly damaged cells in each disease. Furthermore, treatments that should be immediately initiated in clinical practice for each disease are illustrated to save patients with these diseases.

Frequency, proportion of PF-ILD, and prognostic factors in patients with acute exacerbation of ILD related to systemic autoimmune diseases

BACKGROUND

Acute exacerbation (AE) of systemic autoimmune disease-related interstitial lung diseases (SAID-ILD) is less common than AE of idiopathic pulmonary fibrosis (IPF) and the details of AE-SAID-ILD have not been elucidated, but the prognosis is similarly devastating. This study was undertaken to determine the incidences of AE-ILD in each SAID and to elucidate the proportion of progressive fibrosing (PF)-ILD in AE-SAID-ILD.

METHODS

We retrospectively analysed data for patients with SAID-ILD who were diagnosed and observed at our hospital between 1999 and 2020.

RESULTS

Two hundred and thirty-two patients with SAID-ILD were enrolled, with a mean observation period of 100.2 months. AE-SAID-ILD was found in 25 patients (10.78%), mainly in patients with RA (17 patients, 68%) and elderly male patients with a smoking history. The overall incidence of AE-SAID-ILD was 1.29%/person-year, and the incidence for each SAID was as follows: RA 2.193, microscopic polyarteritis (MPA) 3.203, systemic sclerosis (SSc) 2.277, primary Sjögren syndrome 0.426, and polymyositis/dermatomyositis 0.222. The incidence of AE of RA/MPA/SSc-ILD was significantly higher than that of other AE-SAID-ILD (p < 0.001). Five of 25 patients (20%) fulfilled the criteria for PF-ILD. The 90-day survival rate was 48.0%, and a higher neutrophil count at AE (HR 13.27, 95%CI 2.447-246, p = 0.001) and early commencement of long-duration direct haemoperfusion with a polymyxin B-immobilised fibre column (HR 0.105, 95%CI 0.005-0.858, p = 0.035) were significant prognostic factors.

CONCLUSIONS

The incidence of AE-SAID-ILD was significantly higher in patients with RA, MPA, or SSc than in patients with other SAID. Furthermore, even in patients with AE-SAID-ILD, the proportion of PF-ILD just before AE was not high (20%).

Prognosis of acute exacerbation in idiopathic pulmonary fibrosis with pulmonary emphysema: a retrospective cohort study in Japan

OBJECTIVES

To analyse the clinical characteristics and prognosis of acute exacerbation (AE) in patients with idiopathic pulmonary fibrosis (IPF) and pulmonary emphysema.

DESIGN

A multicentre retrospective cohort study SETTING: Two university hospitals in Japan PARTICIPANTS: Patients admitted to hospitals due to AE of IPF diagnosed based on a multidisciplinary discussion.

INTERVENTIONS

None PRIMARY AND SECONDARY OUTCOME MEASURES: 90-day mortality rate METHODS: We retrospectively analysed consecutive patients with AE of IPF, with or without pulmonary emphysema, admitted to two university hospitals between 2007 and 2018.

RESULTS

Among 62 patients (median age, 75 years; 48 men) admitted for AE of IPF, 29 patients (46%) presented with concomitant pulmonary emphysema. There was no significant difference in the arterial partial oxygen pressure/fraction of inhaled oxygen (P/F) ratio or other laboratory and radiographic data between patients with and without emphysema. The 90-day mortality rate was significantly lower in patients with emphysema than in those with IPF alone (23% vs 52%, p=0.03). The median survival time was significantly longer in patients with emphysema than in those with IPF alone (405 vs 242 days, p=0.02).

CONCLUSION

Patients with IPF and emphysema had better short-term survival after AE than those with non-emphysematous IPF.

[French practical guidelines for the diagnosis and management of IPF - 2021 update, full version]

BACKGROUND

Since the previous French guidelines were published in 2017, substantial additional knowledge about idiopathic pulmonary fibrosis has accumulated.

METHODS

Under the auspices of the French-speaking Learned Society of Pulmonology and at the initiative of the coordinating reference center, practical guidelines for treatment of rare pulmonary diseases have been established. They were elaborated by groups of writers, reviewers and coordinators with the help of the OrphaLung network, as well as pulmonologists with varying practice modalities, radiologists, pathologists, a general practitioner, a head nurse, and a patients' association. The method was developed according to rules entitled "Good clinical practice" in the overall framework of the "Guidelines for clinical practice" of the official French health authority (HAS), taking into account the results of an online vote using a Likert scale.

RESULTS

After analysis of the literature, 54 recommendations were formulated, improved, and validated by the working groups. The recommendations covered a wide-ranging aspects of the disease and its treatment: epidemiology, diagnostic modalities, quality criteria and interpretation of chest CT, indication and modalities of lung biopsy, etiologic workup, approach to familial disease entailing indications and modalities of genetic testing, evaluation of possible functional impairments and prognosis, indications for and use of antifibrotic therapy, lung transplantation, symptom management, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are aimed at guiding the diagnosis and the management in clinical practice of idiopathic pulmonary fibrosis.

French practical guidelines for the diagnosis and management of idiopathic pulmonary fibrosis - 2021 update. Full-length version

BACKGROUND

Since the latest 2017 French guidelines, knowledge about idiopathic pulmonary fibrosis has evolved considerably.

METHODS

Practical guidelines were drafted on the initiative of the Coordinating Reference Center for Rare Pulmonary Diseases, led by the French Language Pulmonology Society (SPLF), by a coordinating group, a writing group, and a review group, with the involvement of the entire OrphaLung network, pulmonologists practicing in various settings, radiologists, pathologists, a general practitioner, a health manager, and a patient association. The method followed the "Clinical Practice Guidelines" process of the French National Authority for Health (HAS), including an online vote using a Likert scale.

RESULTS

After a literature review, 54 guidelines were formulated, improved, and then validated by the working groups. These guidelines addressed multiple aspects of the disease: epidemiology, diagnostic procedures, quality criteria and interpretation of chest CT scans, lung biopsy indication and procedures, etiological workup, methods and indications for family screening and genetic testing, assessment of the functional impairment and prognosis, indication and use of antifibrotic agents, lung transplantation, management of symptoms, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are intended to guide the diagnosis and practical management of idiopathic pulmonary fibrosis.

COVID-19-Triggered Acute Exacerbation of IPF, an Underdiagnosed Clinical Entity With Two-Peaked Respiratory Failure: A Case Report and Literature Review

Because severe coronavirus disease 2019 (COVID-19) affects the respiratory system and develops into respiratory failure, patients with pre-existing chronic lung disorders, such as idiopathic pulmonary fibrosis (IPF), are thought to be at high risk of death. Patients with IPF often suffer from a lethal complication, acute exacerbation (AE), a significant part of which is assumed to be triggered by respiratory viral infection. However, whether mild to moderate COVID-19 can trigger AE in patients with IPF remains unknown. This is the case report of a 60-year-old man with a 4-year history of IPF who successfully recovered from moderate COVID-19 but subsequently developed more severe respiratory failure, which was considered to be a COVID-19-triggered acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF). It is important to be aware of the risk of AE-IPF after COVID-19 and to properly manage this deadly complication of IPF. Recent literature reporting cases with chronic interstitial lung diseases which developed respiratory failure by complications with COVID-19 is also reviewed and discussed.

Acute exacerbation of interstitial lung disease associated with rheumatic disease

Interstitial lung disease (ILD) is a cause of morbidity and mortality in patients with rheumatic diseases, such as connective-tissue diseases, rheumatoid arthritis and systemic vasculitis. Some patients with ILD secondary to rheumatic disease (RD-ILD) experience acute exacerbations, with sudden ILD progression and high mortality during or immediately after the exacerbation, and a very low 1-year survival rate. In the ILD subtype idiopathic pulmonary fibrosis (IPF), an acute exacerbation is defined as acute worsening or development of dyspnoea associated with new bilateral ground-glass opacities and/or consolidations at high-resolution CT, superimposed on a background pattern consistent with fibrosing ILD. However, acute exacerbation in RD-ILD (AE-RD-ILD) currently has no specific definition. The aetiology and pathogenesis of AE-RD-ILD remain unclear, but distinct triggers might include infection, mechanical stress, microaspiration and DMARD treatment. At this time, no effective evidence-based therapeutic strategies for AE-RD-ILD are available. In clinical practice, AE-RD-ILD is often empirically treated with high-dose systemic steroids and antibiotics, with or without immunosuppressive drugs. In this Review, we summarize the clinical features, diagnosis, management and prognosis of AE-RD-ILD, enabling the similarities and differences with acute exacerbation in IPF to be critically assessed.

New risk scoring system for predicting 3-month mortality after acute exacerbation of idiopathic pulmonary fibrosis

Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is often fatal. A straightforward staging system for AE-IPF would improve prognostication, guide patient management, and facilitate research. The aim of study is to develop a multidimensional prognostic AE-IPF staging system that uses commonly measured clinical variables. This retrospective study analyzed data from 353 consecutive patients with IPF admitted to our hospital during the period from January 2008 through January 2018. Multivariate analysis of information from a database of 103 recorded AE-IPF cases was used to identify factors associated with 3-month mortality. A clinical prediction model for AE-IPF was developed by using these retrospective data. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance of this model. Logistic regression analysis showed that PaO₂/FiO₂ ratio, diffuse HRCT pattern, and serum C-reactive protein (CRP) were significantly associated with 3-month mortality; thus, PaO₂/FiO₂ ratio < 250 (P), CRP ≥ 5.5 (C), and diffuse HRCT pattern (radiological) (R) were included in the final model. A model using continuous predictors and a simple point-scoring system (PCR index) was developed. For the PCR index, the area under the ROC curve was 0.7686 (P < 0.0001). The sensitivity of the scoring system was 78.6% and specificity was 67.8%. The PCR index identified four severity grades (0, 1, 2, and 3), which were associated with a 3-month mortality of 7.7%, 29.4%, 54.8%, and 80%, respectively. The present PCR models using commonly measured clinical and radiologic variables predicted 3-month mortality in patients with AE-IPF.

Acute exacerbation of interstitial lung disease in the intensive care unit

Acute exacerbations of interstitial lung disease (AE-ILD) represent an acute, frequent and often highly morbid event in the disease course of ILD patients. Admission in the intensive care unit (ICU) is very common and the need for mechanical ventilation arises early. While non-invasive ventilation has shown promise in staving off intubation in selected patients, it is unclear whether mechanical ventilation can alter the exacerbation course unless it is a bridge to lung transplantation. Risk stratification using clinical and radiographic findings, and early palliative care involvement, are important in ICU care. In this review, we discuss many of the pathophysiological aspects of AE-ILD and raise the hypothesis that ventilation strategies used in acute respiratory distress syndrome might be implemented in AE-ILD. We present possible decision-making and management algorithms that can be used by the intensivist when caring for these patients.

Visual classification of three computed tomography lung patterns to predict prognosis of COVID-19: a retrospective study

Background

Quantitative evaluation of radiographic images has been developed and suggested for the diagnosis of coronavirus disease 2019 (COVID-19). However, there are limited opportunities to use these image-based diagnostic indices in clinical practice. Our aim in this study was to evaluate the utility of a novel visually-based classification of pulmonary findings from computed tomography (CT) images of COVID-19 patients with the following three patterns defined: peripheral, multifocal, and diffuse findings of pneumonia. We also evaluated the prognostic value of this classification to predict the severity of COVID-19.

Methods

This was a single-center retrospective cohort study of patients hospitalized with COVID-19 between January 1st and September 30^th, 2020, who presented with suspicious findings on CT lung images at admission (n = 69). We compared the association between the three predefined patterns (peripheral, multifocal, and diffuse), admission to the intensive care unit, tracheal intubation, and death. We tested quantitative CT analysis as an outcome predictor for COVID-19. Quantitative CT analysis was performed using a semi-automated method (Thoracic Volume Computer-Assisted Reading software, GE Health care, United States). Lungs were divided by Hounsfield unit intervals. Compromised lung (%CL) volume was the sum of poorly and non-aerated volumes (− 500, 100 HU). We collected patient clinical data, including demographic and clinical variables at the time of admission.

Results

Patients with a diffuse pattern were intubated more frequently and for a longer duration than patients with a peripheral or multifocal pattern. The following clinical variables were significantly different between the diffuse pattern and peripheral and multifocal groups: body temperature (p = 0.04), lymphocyte count (p = 0.01), neutrophil count (p = 0.02), c-reactive protein (p < 0.01), lactate dehydrogenase (p < 0.01), Krebs von den Lungen-6 antigen (p < 0.01), D-dimer (p < 0.01), and steroid (p = 0.01) and favipiravir (p = 0.03) administration.

Conclusions

Our simple visual assessment of CT images can predict the severity of illness, a resulting decrease in respiratory function, and the need for supplemental respiratory ventilation among patients with COVID-19.

Acute Exacerbation of Idiopathic Pulmonary Fibrosis

Acute exacerbation is a major cause of morbidity and mortality in patients with idiopathic pulmonary fibrosis. Although the real nature of it is still not clear and there is no proven effective therapy, progress has been made since the consensus definition and diagnostic criteria were proposed. The trial results of several new innovative therapies in idiopathic pulmonary fibrosis have suggested a potential for benefit in acute exacerbation of idiopathic pulmonary fibrosis, leading to double blind randomized clinical trials in this area. This article reviews the present knowledge on acute exacerbation of idiopathic pulmonary fibrosis, focusing on the triggering factors and treatment.

Hemosiderin-Laden Macrophages in Bronchoalveolar Lavage: Predictive Role for Acute Exacerbation of Idiopathic Interstitial Pneumonias

Background

Hemosiderin-laden macrophages (HLMs) have been identified in the bronchoalveolar lavage fluid (BALF) of patients with idiopathic pulmonary fibrosis (IPF). This retrospective study examined the ability of HLMs in BALF to predict the acute exacerbation (AE) of chronic idiopathic interstitial pneumonias (IIPs).

Methods

Two hundred and twenty-one patients with IIP diagnosed by bronchoscopy were enrolled in the study (IPF, n = 87; IIPs other than IPF, n = 134). Giemsa stain was used to detect HLMs in BALF specimens. Prussian blue stain was used to quantify HLMs in BALF, and a hemosiderin score (HS) was given to the specimens containing HLMs.

Results

Twenty-four patients had a positive HS (range: 7‒132). The receiver-operating characteristic curve analysis identified the cutoff HS value for predicting the AE of IIPs to be 61.5. Seven cases had a higher HS (≥61.5) and 214 had a lower HS. AE occurred significantly earlier in the higher HS group (4/7 cases) than in the lower HS group (41/214 cases) during a median observation period of 1239 days (log-rank test, p = 0.026). Multivariate Cox proportional hazard regression analysis showed that a higher HS was a significant predictor of AE in addition to IPF, percent predicted forced vital capacity, and modified Medical Research Council score. The C-statistics for the prediction of AE did not significantly improve by all the above parameters with HS as compared without HS.

Conclusions

A higher HS was a significant predictor of AE in IIPs but did not significantly improve the predictive ability of other parameters.

Tolerability and efficacy of second-line antifibrotics in patients with idiopathic pulmonary fibrosis

BACKGROUND

The antifibrotic drugs nintedanib and pirfenidone reduce disease progression in idiopathic pulmonary fibrosis (IPF) and have also shown to improve survival. Switching first-line antifibrotic drug may required in IPF due to disease progression or intolerable adverse effects. The aim of this study was to assess the safety and efficacy of second-line antifibrotic treatment in patients with IPF.

MATERIAL AND METHODS

This retrospective, multicenter study was conducted at three referral interstitial lung disease centers who received first-line antifibrotics more than one month and switched the treatment to a second-line antifibrotic agent during January 2016-June 2021. The drug's safety was evaluated based on the type of adverse effect. Disease progression was defined as an absolute decline in FVC of >10% within 12 months with or without radiological progression.

RESULTS

Among 629 consecutive patients with IPF, 66 patients switched antifibrotics. The median duration of antifibrotics was 13 (1-41) months prior to the switch, and 14 (2-42) months after the switch. The mean age was 70.6 ± 8.9 years and, median FVC (%) was 72.1 ± 18.7 at the initiation of first-line antifibrotics. The most common reason for the switch was disease progression (56%) followed by severe adverse effects (SAEs) (44%). SAEs were significantly less observed after the switch compared before the switch (43.9% vs12.1%, respectively, p < 0.001). Eighteen patients had adverse effects due to second-line antifibrotics. Among these patients, 10 had mild adverse effects and 8 had severe adverse effects. While there was no change in the FVC (%) values in 30.3% patients 12 months after the first-line antifibrotic treatment (before the switch), there was no change in the FVC (%) values in 40% patients at the end of 12 months after the switch. Fourteen patients (42.4%) who received antifibrotic treatment before the switch had more than 10% decline in FVC (%) at the end of 12 months. Eight patients (32.0%) had 10% or more decline in FVC (%) 12 months after the switch.

CONCLUSION

Patients with IPF who do not tolerate first-line antifibrotic treatment or those showing disease progression despite treatment, switching antifibrotics may be a feasible management strategy.

ERS International Congress 2020 Virtual: highlights from the Respiratory Intensive Care Assembly

During the virtual European Respiratory Society Congress 2020, early career members summarised the sessions organised by the Respiratory Intensive Care Assembly. The topics covered included diagnostic strategies in patients admitted to the intensive care unit with acute respiratory failure, with a focus on patients with interstitial lung disease and for obvious reasons, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. These sessions are summarised in this article, with take-home messages highlighted.

Updates from #ERSCongress 2020 on diagnostic strategies in patients admitted to the ICU with acute respiratory failure and on the management of #SARSCoV2 infectionhttps://bit.ly/38cx0Pi

ACR Appropriateness Criteria® Diffuse Lung Disease

Diffuse lung disease, frequently referred to as interstitial lung disease, encompasses numerous disorders affecting the lung parenchyma. The potential etiologies of diffuse lung disease are broad with several hundred established clinical syndromes and pathologies currently identified. Imaging plays a critical role in diagnosis and follow-up of many of these diseases, although multidisciplinary discussion is the current standard for diagnosis of several DLDs. This document aims to establish guidelines for evaluation of diffuse lung diseases for 1) initial imaging of suspected diffuse lung disease, 2) initial imaging of suspected acute exacerbation or acute deterioration in cases of confirmed diffuse lung disease, and 3) clinically indicated routine follow-up of confirmed diffuse lung disease without acute deterioration. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Idiopathic Interstitial Pneumonias and COVID-19 Pneumonia: Review of the Main Radiological Features and Differential Diagnosis

COVID-19 pneumonia represents a challenging health emergency, due to the disproportion between the high transmissibility, morbidity, and mortality of the virus and healthcare systems possibilities. Literature has mainly focused on COVID-19 pneumonia clinical-radiological diagnosis and therapy, and on the most common differential diagnoses, while few papers investigated rare COVID-19 pneumonia differential diagnoses or the overlapping of COVID-19 pneumonia on pre-existing lung pathologies. This article presents the main radiological characteristics of COVID-19 pneumonia and Idiopathic Interstitial Pneumonias (IIPs) to identify key radiological features for a differential diagnosis among IIPs, and between IIPs and COVID-19 pneumonia. COVID-19 pneumonia differential diagnosis with IIPs is challenging, since these entities may share common radiological findings as ground glass opacities, crazy paving patterns, and consolidations. Multidisciplinary discussion is crucial to reach a final and correct diagnosis. Radiologists have a pivotal role in identifying COVID-19 pneumonia patterns, reporting possible overlapping with long-lasting lung diseases, and suggesting potential differential diagnoses. An optimal evaluation of HRTC may help in containing the disease, in promoting better treatment for patients, and in providing an efficient allocation of human and economic resources.

Prognostic significance of bronchoalveolar lavage cellular analysis in patients with acute exacerbation of interstitial lung disease

BACKGROUND

Acute exacerbation (AE) of interstitial lung disease (ILD) is an acute respiratory deterioration of unknown etiology, associated with high mortality. Currently, bronchoalveolar lavage (BAL) has been no longer required for the diagnosis of AE-ILD; however, the clinical utility of BAL fluid (BALF) cellular analysis in AE-ILD remains unclear.

METHODS

A retrospective study of 71 patients who underwent BAL at our institution between 2005 and 2019 and were diagnosed with AE-ILD was conducted. We performed BALF cellular analysis and evaluated its prognostic significance.

RESULTS

There were 26 patients with AE of idiopathic pulmonary fibrosis (IPF) and 45 with AE of non-IPF, including idiopathic interstitial pneumonias/non-IPF (n = 22), ILD associated with collagen tissue disease (n = 20) and fibrotic hypersensitivity pneumonia (n = 3). All patients were treated with high-dose corticosteroids, and the 90-day mortality after AE was 31%. Most patients showed a high percentage of lymphocytes and/or neutrophils in BALF regardless of the underlying ILD. There was a significant negative correlation between BALF neutrophils and the PaO₂/FiO₂ ratio, and patients with UIP pattern or diffuse AE pattern on HRCT had a significantly higher percentage of BALF neutrophils than those with other patterns. Multivariate analysis revealed that lower and higher percentage of lymphocytes and neutrophils, respectively, in BALF were independent poor prognostic factors for 90-day survival. BALF lymphocyte and neutrophil count ≥25% and <20%, respectively, predicted favorable survival after AE.

CONCLUSIONS

Cellular analysis of BALF in AE-ILD is a potential biomarker for predicting prognosis after AE.

Prognostic significance of serum cytokines during acute exacerbation of idiopathic interstitial pneumonias treated with thrombomodulin

BACKGROUND

Acute exacerbation (AE) has been reported to herald a poor prognosis in idiopathic pulmonary fibrosis and is now thought to do so in idiopathic interstitial pneumonias (IIPs). However, the pathophysiology of AE-IIPs is not sufficiently understood. In our previously reported SETUP trial, we found better survival in patients with AE-IIPs treated with corticosteroids and thrombomodulin than in those treated with corticosteroids alone. In that study, we collected serum samples to evaluate changes in cytokine levels and retrospectively examined the prognostic significance and pathophysiological role of serum cytokines in patients with AE-IIPs.

METHODS

This study included 28 patients from the SETUP trial for whom serial serum samples had been prospectively obtained. AE-IIPs were diagnosed using the Japanese Respiratory Society criteria. All patients were treated with intravenous thrombomodulin and corticosteroids from 2014 to 2016. Serum levels of 27 cytokines were measured using Bio-Plex. The high-resolution CT pattern at the time of diagnosis of AE was classified as diffuse or non-diffuse.

RESULTS

Univariate analysis revealed that higher serum levels of interleukin (IL)-2, IL-7, IL-9, IL-12, IL13, basic fibroblast growth factor, granulocyte-macrophage colony-stimulating factor, interferon-γ inducible protein-10, platelet-derived growth factor and regulated on activation, normal T cell expressed and secreted (RANTES) at AE were significant predictors of 90-day survival. The HRCT pattern was also a significant clinical predictor of 90-day survival. Multivariate analysis with stepwise selection identified a higher serum RANTES level at AE to be a significant predictor of 90-day survival, including after adjustment for HRCT pattern. Multivariate analysis with stepwise selection suggested that a marked increase in the serum IL-10 level on day 8 could predict 90-day mortality.

CONCLUSIONS

A higher serum RANTES level at AE the time of diagnosis predicted a good survival outcome, and an elevated serum IL-10 level on day 8 predicted a poor survival outcome.

TRIAL REGISTRATION NUMBER

UMIN000014969.

Efficacy of recombinant thrombomodulin for poor prognostic cases of acute exacerbation in idiopathic interstitial pneumonia: secondary analysis of the SETUP trial

Background

Acute exacerbation (AE) in idiopathic pulmonary fibrosis and other idiopathic interstitial pneumonias (IIPs) are poor prognostic events although they are usually treated with conventional therapy with corticosteroids and immunosuppressants. Previously, we demonstrated the safety and efficacy of recombinant human soluble thrombomodulin (rhTM) for AE-IIP in the SETUP trial. Here, we aimed to clarify the efficacy of rhTM for poor-prognosis cases of AE-IIP.

Methods

In this study, we included 85 patients, in whom fibrin degradation product (FDP)/d-dimer was evaluated at AE, from the 100 patients in the SETUP trial. The AE-IIP patients in the rhTM arm (n=39) were diagnosed using the Japanese criteria from 2014 to 2016 and treated with intravenous rhTM for 6 days in addition to the conventional therapy. The AE-IIP patients in the control arm (n=46) were treated with the conventional therapy without rhTM between 2011 and 2013. The subjects were classified into higher and lower FDP/d-dimer groups based on the Japanese Association for Acute Medicine Disseminated Intravascular Coagulation scoring system. A multivariate Cox proportional hazard regression analysis with stepwise selection was performed to reveal the prognostic factors of AE-IIP.

Results

We developed a prognostic scoring system using two significant prognostic factors, higher FDP/d-dimer at AE and prednisolone therapy before AE, with 3 and 2 points assigned for each parameter, respectively. The prognostic scores ranged from 0 to 5. Survival of AE-IIP patients with a prognostic score=0 was significantly better than that of patients with score ≥2. Survival was improved with the rhTM therapy (p<0.05) in the poor prognostic cases (score ≥2), but not in the good prognostic cases (score=0).

Conclusions

Treatment with rhTM might improve survival in AE-IIP cases with poor prognoses.

Trial registration number

UMIN000014969, date: 28 August 2014.

Acute exacerbation of unclassifiable idiopathic interstitial pneumonia: comparison with idiopathic pulmonary fibrosis

Background:

Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is well known as a life-threatening condition during its clinical course. However, the clinical features and prognosis in AE of unclassifiable idiopathic interstitial pneumonia (AE-UCIIP) remain to be elucidated. The aim of this study was to clarify the clinical features and prognosis of AE-UCIIP compared with those of AE-IPF.

Methods:

In 187 patients with UCIIP or IPF, 64 patients with AE-UCIIP or AE-IPF, who were diagnosed and treated at our hospital, were retrospectively evaluated.

Results:

A total of 24 patients with AE-UCIIP were significantly older (p = 0.011), included more women (p < 0.001) and never-smokers (p < 0.001), and showed fewer lung lesions on high-resolution computed tomography (p = 0.006) than 40 patients with AE-IPF. Incidence of AE-UCIIP was 10.29%/year and was significantly higher than in AE-IPF (Gray’s test, p = 0.008). Prognosis of AE-UCIIP was as poor as that of AE-IPF (log-rank, p = 0.681). Percent-predicted forced vital capacity (%FVC) [hazard ratio (HR) 0.934, p = 0.045], and GAP stage within 12 months before AE (HR 3.530, p = 0.023), and partial pressure arterial oxygen/fraction of inspired oxygen (PaO₂/FiO₂) ratio at AE (HR 0.998, p = 0.016) were significant prognostic factors. Finally, commencement of long-duration (⩾12 h) direct hemoperfusion with a polymyxin B-immobilised fibre column (PMX-DHP) within 2 days after admission significantly improved survival (log-rank, p = 0.038) and was a significant prognostic factor (HR 0.175, p = 0.0039) in AE-UCIIP. Long-duration PMX-DHP showed favourable treatment effects even in the combined group of patients with AE-UCIIP or AE-IPF (log-rank p = 0.002; HR 0.328, p = 0.006).

Conclusions:

Patients with AE-UCIIP were older and included more women and never-smokers than those with AE-IPF. Prognosis of AE-UCIIP was as poor as that of AE-IPF.

The reviews of this paper are available via the supplemental material section.

Chest-CT mimics of COVID-19 pneumonia-a review article

Coronavirus disease 2019 (COVID-19) emerged in early December 2019 in China, as an acute lower respiratory tract infection and spread rapidly worldwide being declared a pandemic in March 2020. Chest-computed tomography (CT) has been utilized in different clinical settings of COVID-19 patients; however, COVID-19 imaging appearance is highly variable and nonspecific. Indeed, many pulmonary infections and non-infectious diseases can show similar CT findings and mimic COVID-19 pneumonia. In this review, we discuss clinical conditions that share a similar imaging appearance with COVID-19 pneumonia, in order to identify imaging and clinical characteristics useful in the differential diagnosis.

Association of serum monomeric periostin level with outcomes of acute exacerbation of idiopathic pulmonary fibrosis and fibrosing nonspecific interstitial pneumonia

Background

The associations of serum monomeric periostin (M-PN) level and serial change in M-PN with acute exacerbation of chronic fibrosing interstitial pneumonia (AE-FIP) are unclear.

Methods

We prospectively measured serum M-PN level from onset of AE to day 14 in 37 patients with AE-FIP and evaluated its association with outcome. To determine localization of periostin expression, immunohistochemical staining of pathological lung tissue from autopsy cases of AE-IPF was evaluated.

Results

Data from 37 AE-FIP patients (28 men; age 73.9±7.8 years) were analyzed. With healthy controls as reference, serum M-PN level was significantly higher in patients with AE-FIP (P=0.02) but not in those with stable idiopathic pulmonary fibrosis (P=1.00). M-PN was significantly lower on day 7 than at AE-FIP onset in survivors [14.6±5.8 vs. 9.3±2.8 ng/mL (onset to day 7: P<0.001)] but not in non-survivors [14.6±5.1 vs. 13.2±5.1 ng/mL (onset to day 7: P=0.07)]. In analysis using a cut-off value for serial change in M-PN (ΔM-PN), 3-month survival was 92.3% in the ΔM-PN decrease group and 36% in the ΔM-PN increase group (P=0.002). In multivariate analysis, 3-month survival tended to be associated with high ΔM-PN (OR: 12.4, 95% CI: 0.82–187.9, P=0.069).

Conclusions

Serial change in serum M-PN level may be a prognostic indicator of AE-FIP.

Prognostic classification in acute exacerbation of idiopathic pulmonary fibrosis: a multicentre retrospective cohort study

Acute exacerbation (AE) in idiopathic pulmonary fibrosis (IPF) is a major prognostic determinant. However, evidence for its prognostic strength is mainly based on the results of small cohort studies with statistical limitations. This retrospective study, which included 108 patients with a first episode of AE-IPF, aimed to identify prognostic factors and to develop prognostic classification models. Multivariate Cox regression analysis revealed that a lower percent-predicted forced vital capacity within 12 months before AE onset (baseline %FVC) and a lower PaO₂/FiO₂ ratio at AE onset were independent mortality predictors. If the value of each predictor was lower than the cutoff determined by receiver-operating characteristic analysis, 1 point was assigned. Classification of patients into mild, moderate, and severe groups based on total score showed post-AE 90-day cumulative survival rates of 83.3%, 66.2%, and 22.2%, respectively (model 1: C-index 0.702). Moreover, a decision tree-based model was created with the recursive partitioning method using baseline %FVC and PaO₂/FiO₂ ratio at AE onset from among multivariable; accordingly, patients were classified into 3 groups with post-AE 90-day cumulative survival rates of 84.1%, 64.3%, and 24.0%, respectively (model 2: C-index 0.735). These models can guide clinicians in determining therapeutic strategies and help design future studies on AE-IPF.

Diagnosis of idiopathic pulmonary fibrosis

Interstitial lung disease (ILD) is a group of diseases, involving the inflammation and fibrosis of the interstitium of the lung. ILD is classified according to whether or not the cause is known. Known causes of ILDs include inhalation of environmental substances, drugs, infection, and related connective tissue disease. ILD of unknown cause is called idiopathic ILD. The most common form of idiopathic ILD is idiopathic pulmonary fibrosis (IPF). IPF is a chronic progressive fibrosing ILD that results in the decline of lung function with exertional dyspnea, cough, bibasilar inspiratory crackles, and digital clubbing. The incidence of IPF increases with age, and is predominant in men. The most characteristic feature of IPF is a usual interstitial pneumonia (UIP) pattern detected on high-resolution computed tomography (HRCT). The typical HRCT pattern in case of UIP is honeycombing, with or without traction bronchiectasis or bronchiolectasis; this may be superimposed with fine reticulation. The typical distribution of UIP is subpleural, and there is basal predominance with heterogeneity. A definitive diagnosis of IPF in patients with clinically suspected IPF is made when there is presence of a UIP pattern on HRCT. Bronchoalveolar lavage or surgical lung biopsy is not recommended if a UIP pattern is detected on HRCT. However, bronchoalveolar lavage and surgical lung biopsy are required if probable UIP pattern, indeterminate UIP pattern, or an alternative diagnosis pattern are found on HRCT in order to diagnose IPF. A specific combination of HRCT patterns and histopathological patterns requiring multidisciplinary discussion is necessary to rule in IPF or rule it out.

Practical Imaging Interpretation in Patients Suspected of Having Idiopathic Pulmonary Fibrosis: Official Recommendations from the Radiology Working Group of the Pulmonary Fibrosis Foundation

Imaging serves a key role in the diagnosis of patients suspected of having idiopathic pulmonary fibrosis (IPF). Accurate pattern classification at thin-section chest CT is a key step in multidisciplinary discussions, guiding the need for surgical lung biopsy and determining available pharmacologic therapies. The recent approval of new treatments for fibrosing lung disease has made it more critical than ever for radiologists to facilitate accurate and early diagnosis of IPF. This document was developed by the Radiology Working Group of the Pulmonary Fibrosis Foundation with the goal of providing a practical guide for radiologists. In this review, the critical imaging patterns of IPF, pitfalls in imaging classifications, confounding imaging findings with other fibrotic lung diseases, and reporting standards for cases of lung fibrosis will be discussed.

Published under a CC BY 4.0 license.

See also the commentary by White and Galvin in this issue.

S2K Guideline for Diagnosis of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a severe and often fatal disease. Diagnosis of IPF requires considerable expertise and experience. Since the publication of the international IPF guideline in the year 2011 and the update 2018 several studies and technical advances have occurred, which made a new assessment of the diagnostic process mandatory. The goal of this guideline is to foster early, confident, and effective diagnosis of IPF. The guideline focusses on the typical clinical context of an IPF patient and provides tools to exclude known causes of interstitial lung disease including standardized questionnaires, serologic testing, and cellular analysis of bronchoalveolar lavage. High-resolution computed tomography remains crucial in the diagnostic workup. If it is necessary to obtain specimens for histology, transbronchial lung cryobiopsy is the primary approach, while surgical lung biopsy is reserved for patients who are fit for it and in whom a bronchoscopic diagnosis did not provide the information needed. After all, IPF is a diagnosis of exclusion and multidisciplinary discussion remains the golden standard of diagnosis.

COVID-19: looking beyond the peak. Challenges and tips for radiologists in follow-up of a novel patient cohort

As the coronavirus pandemic evolves, the focus of radiology departments has begun to change. The acute phase of imaging a new disease entity whilst rationalising radiology services in the face of lockdown has passed. Radiologists are now becoming familiar with the complications of COVID-19, particularly the lung parenchymal and pulmonary vascular sequelae and are considering the impact follow-up imaging may have on departments already struggling with a backlog of suspended imaging in the face of reduced capacity. This review from the British Society of Thoracic Imaging explores both the thoracic and extra-thoracic complications of COVID-19, recognising the importance of a holistic approach to patient follow-up. The British Thoracic Society guidelines for respiratory follow-up of COVID-19 will be discussed, together with newly developed reporting templates, which aim to provide consistency for clinicians as well as an opportunity for longer-term data collection.

Update in Diagnosis of Idiopathic Pulmonary Fibrosis and Interstitial Lung Abnormality

최신 국제 임상진료지침을 기반으로 한 특발폐섬유증의 진단은 부합하는 임상 소견과 함께 고해상 CT에서 전형적인 상용간질폐렴 소견을 보일 때 조직학적 폐 생검 없이 진단 가능하다. 영상 검사는 특발폐섬유증의 평가 및 진단에 중추적인 역할을 하며, 정확한 진단을 위하여 임상적, 영상의학적 및 병리학적 소견에 대한 다학제 검토의 중요성이 강조된다. 간질성 폐이상(interstitial lung abnormality)은 우연히 발견된 영상의학적 이상 소견을 지칭하며, 간질성폐이상과 임상적으로 의미 있는 간질폐질환에 대한 구분은 적절한 임상 평가를 기반으로 이루어져야 한다. 저자들은 이번 종설을 통하여 특발폐섬유증 진단의 최신 지견 및 간질성폐이상에 대한 이해를 도움으로써 미만성 간질폐섬유증 환자의 정확한 진단과 치료 및 예후 증진에 도움이 되고자 한다.

Serum Krebs von den Lungen (KL-6) level as a marker of exacerbation of interstitial lung diseases

Background

Krebs von den Lungen (KL-6) is elevated in serum of interstitial lung disease (ILD) patients based on its leakage from the alveolar space into the blood; KL-6 is significantly higher in patients with acute exacerbation of ILDs (AE-ILD) compared with stable patients. This study aimed to determine the sensitivity and specificity of KL6 to detect AE-ILD.

Results

This is a prospective cross sectional observational study was carried out on 88 subjects at the Chest Department, Minia Cardiothoracic University Hospital, during the period from August 2018 to August 2019. This study was approved by the hospital research ethics board of Minia University and informed consent was obtained. History, examination, spirometry, ABGs, X-ray, HRCT, CBC, ESR, CRP, and KL6 levels were done to both stable and exacerbation groups of ILDs. The level of biomarkers is compared between both groups and control.

Statistical analysis done by using IBM SPSS statistical package version 20 (χ2 test and independent sample t test, ANOVA test, bivariate Pearson correlation analysis, and ROC curve analysis).

The study showed that there is a significant difference between stable and exacerbating groups regarding fever, signs of RHF, dyspnea scale, FVC, and PaO2.

Conclusion

KL-6 cutoff ≥ 187.5 U/ml could exhibit AE-ILDs with a sensitivity of 98% and a specificity of 97%. KL-6 is a more sensitive and specific marker to detect AE-ILD.

Pharmacological management of Idiopathic Pulmonary Fibrosis: current and emerging options

INTRODUCTION

Idiopathic Pulmonary Fibrosis is a chronic, progressive lung disease characterized by worsening lung scarring and the radiological/histological pattern of usual interstitial pneumonia. Substantial progress has been made in the clinical management of IPF in the last decade. The two novel antifibrotics, Nintedanib and Pirfenidone have changed the landscape of IPF, by hindering disease progression; however, the drugs have significant discontinuation rates, due to adverse events and do not offer a definitive cure, as such IPF remains a deleterious disease with poor survival.

AREAS COVERED

In this review, the authors focus on the current and emerging pharmacological options in the treatment of IPF. They include a summary of the current approach including treatment of comorbidities and then discuss promising drugs in the drug pipeline.

EXPERT OPINION

IPF remains a disease with detrimental outcomes. The plethora of emerging pharmacological treatments brings hope for the future. The current pharmacological 'one fits all' approach has been proven effective in slowing disease progression. The future lies in an oncological approach with combination of therapies. We expect to see a change in clinical trial endpoints and a more inclusive approach for the diagnosis of IPF.

ABBREVIATION LIST

AE: Acute ExacerbationA-SMA: a smooth muscle actinATX: AutotaxinCOPD: Combined Obstructive Pulmonary DiseaseCPFE: Combined Pulmonary Fibrosis and EmphysemaGER: Gastro-esophageal refluxFVC: forced vital capacityECMO: extracorporeal membrane oxygenationILD: Interstitial Lung DiseaseIPF: Idiopathic Pulmonary FibrosisNAC: N-acetylcysteineLPA: Lysophosphatidic acidPH: Pulmonary RehabilitationPR: Pulmonary rehabilitationRCTs: randomized placebo-controlled trialsUIP: usual interstitial pneumonia.

Acute exacerbations of idiopathic pulmonary fibrosis and the role of corticosteroids

An acute exacerbation of idiopathic pulmonary fibrosis (AEIPF) is a potentially fatal complication of an already debilitating disease. Management is currently centred on delivering excellent supportive care and identifying reversible triggers. Despite growing international awareness and collaboration, no effective therapies have been identified. Corticosteroids are often the mainstay of treatment; however, the evidence base for their use is poor. Here, we review our current understanding of the disease process and how to manage it, with a focus on the role of corticosteroid therapy.

Acute exacerbations of IPF cause a rapid deterioration in respiratory status and are challenging to manage. With few other options, corticosteroids are widely used as standard of care; however. the evidence to support this is poor.https://bit.ly/3gvSokN

Seroradiologic prognostic evaluation of acute exacerbation in patients with idiopathic interstitial pneumonia: a retrospective observational study

Background

We previously reported that high-resolution computed tomography (HRCT) patterns and certain serum marker levels can predict survival in patients with acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) and in those with idiopathic interstitial pneumonias (IIPs). The utility of serum marker changes before and during AE has not been previously evaluated. This study aimed to clarify whether changes in serum marker levels could improve the prognostic significance of HRCT patterns in patients with AE-IIPs.

Methods

Seventy-seven patients (60 males, 17 females) with AE-IIP diagnosed between 2004 and 2016 and whose serum Krebs von den Lungen (KL)-6 and surfactant protein (SP)-D levels were measured before and at the onset of AE were enrolled in this study. The HRCT pattern of each patient was classified as diffuse, multifocal, or peripheral. We examined the prognostic significance of the HRCT pattern, increased serum marker levels, and a combination of these parameters using Cox proportional hazard regression analysis.

Results

Fifty-three patients had IPF and 24 had non-IPF IIP. A serum KL-6 level that was increased compared with the level in the stable state (ΔKL-6/ST-KL-6: ≤0.211) was a significantly poor prognostic factor in patients with a multifocal pattern. Multivariate Cox analysis identified long-term oxygen therapy, a partial oxygen tension/fraction of inspired oxygen ratio ≤200 Torr, and an elevated SP-D level during a stable state to be significantly poor prognostic factors in all patients. A diffuse HRCT pattern was not a significant prognostic factor in an AE-IIP in multivariate analysis after adjustment; however, a multifocal pattern accompanying a ΔKL-6/ST-KL-6 ≤0.211 or a diffuse pattern was a significantly poor prognostic factor than a peripheral pattern or a multifocal pattern with ΔKL-6/ST-KL-6 >0.211.

Conclusions

Combining the HRCT pattern and the ΔKL-6/ST-KL-6 value can improve our ability to predict the survival of AE-IIP patients.