Background. Acute exacerbation (AE) is a common cause of rapid deterioration and high mortality in idiopathic pulmonary fibrosis (IPF) patients. Osteopontin (OPN) plays an important role in IPF, but the studies about serum OPN in AE‐IPF are unclear. We aimed to investigate whether OPN had a potential prognostic value in acute exacerbation and mortality in IPF. Methods. Thirty‐two patients with AE‐IPF, 39 with S‐IPF, and 20 healthy controls were included. Serum OPN and KL‐6 levels were compared between AE‐IPF and S‐IPF. Logistic regression analysis was applied to identify the predicted value of OPN for AE. Kaplan–Meier curves were used to display survival, and Cox proportional hazards regression was used to identify risk for mortality. Results. In AE‐IPF patients, serum OPN levels were significantly higher than in S‐IPF subjects (p < 0.001) or healthy controls (p < 0.001). Immunohistochemical staining in lung transplant specimens of IPF showed strong expression of OPN in the alveolar epithelial cells lining honeycomb space and alveolar macrophages accumulating in interalveolar spaces adjacent to the fibrotic lesion. Serum OPN was correlated with higher C‐reactive protein (CRP) and lactate dehydrogenase (LDH). Serum OPN, KL‐6, CRP, LDH, percent forced vital capacity (FVC%), and percent diffusing capacity (DLCO%) in IPF were correlated with AE status, with respective odds ratios of 1.305 (p = 0.004), 1.001 (p = 0.010), 1.039 (p = 0.002), 1.035 (p < 0.001), 0.950 (p = 0.024), and 0.929 (p = 0.010). Serum OPN (above 3.24 ng/ml) was associated with an increasing risk of mortality (p = 0.019). Multivariate Cox regression demonstrated an association of OPN levels with mortality risk (p = 0.036). Conclusion. Elevated OPN could be a potential serum predictor for AE status and survival in IPF patients.

Objective. To investigate prognostic values of serum biomarkers of soluble intercellular adhesion molecule 1 (sICAM-1), macrophage migration inhibitor factor (MIF), interleukin 1β (IL-1β), and soluble urokinase plasminogen activator receptor (su-PAR) in patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF). Methods. From August 2017 to November 2019, 122 consecutive IPF patients treated in our center were classified as stable IPF and AE-IPF based on the newly published international guidelines. Serum levels of four biomarkers at admission were measured by the enzyme-linked immunosorbent assay (ELISA). The primary endpoint was 3-month mortality. The log-rank test and logistic regression analysis were used to evaluate the effects of these biomarkers for survival in patients with AE-IPF. Cox proportional hazards analysis was performed to evaluate the prognostic values of serological biomarkers and clinical data. Results. Eighty-one patients were diagnosed with stable IPF, and 41 AE-IPF patients were enrolled in the study. Serum levels of sICAM-1 (p<0.001), IL-1β (p<0.001), MIF (p<0.001), and su-PAR (p<0.001) in patients with IPF were significantly increased compared to those in healthy controls. All the four biomarkers were elevated in patients with AE-IPF compared to those with stable IPF. The 3-month mortality in AE-IPF was 56.1% (23/41). Increased levels of MIF (p=0.01) and IL-1β (>5 pg/mL, p=0.033) were independent risk factors for 3-month mortality in patients with AE-IPF. Conclusions. We showed the higher serum levels of IL-1β, and MIF had prognostic values for 3-month mortality in AE-IPF. This study provided a clue to promote our understanding in the pathogenesis of the disease.

The prognosis of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is very poor with a high mortality. The aim of this study was to describe the clinical features and survival of patients with AE-IPF with usual pulmonary fibrosis (UIP) and possible UIP (P-UIP) pattern on chest high resolution computed tomography (HRCT). This retrospective study included 107 patients with AE-IPF admitted to Nanjing Drum Tower Hospital from January 2010 to December 2016. The subjects were divided into UIP (n = 86) and P-UIP group (n = 21) based on chest HRCT. Continuous variables were analyzed using Student's t test or Mann-Whitney U test. Categorical variables were analyzed using χ2 test. Log-rank test was used for the survival analysis. Cox proportional models evaluated the risk factors for AE occurrence and survival. The male, older patients, previous N-acetylcysteine use, elevated white blood cell (WBC) counts, and microbiology infection were more common in the UIP group than the P-UIP group (χ2 = 13.567, P z AE occurrence of UIP patients in IIP was significantly higher than P-UIP cases. The short-term survival was better in the UIP group despite of the similar overall survival in the two groups. WBC count, PaO2/FiO2, and CT score were the independent predictors for survival in UIP subjects.

Background: Patients with antimelanoma differentiation–associated gene 5 antibody–positive dermatomyositis–associated interstitial lung disease (anti-MDA5+DM-ILD) are susceptible to rapidly progressive interstitial lung disease (RP-ILD) and have a high risk of mortality. There is an urgent need for a reliable prediction model, accessible via an easy-to-use web-based tool, to evaluate the risk of death. Objective: This study aimed to develop and validate a risk prediction model of 3-month mortality using machine learning (ML) in a large multicenter cohort of patients with anti-MDA5+DM-ILD in China. Methods: In total, 609 consecutive patients with anti-MDA5+DM-ILD were retrospectively enrolled from 6 hospitals across China. Patient demographics and laboratory and clinical parameters were collected on admission. The primary endpoint was 3-month mortality due to all causes. Six ML algorithms (Extreme Gradient Boosting [XGBoost], logistic regression (LR), Light Gradient Boosting Machine [LightGBM], random forest [RF], support vector machine [SVM], and k-nearest neighbor [KNN]) were applied to construct and evaluate the model. Results: After applying inclusion and exclusion criteria, 509 (83.6%) of the 609 patients were included in our study, divided into a training cohort (n=203, 39.9%), an internal validation cohort (n=51, 10%), and 2 external validation cohorts (n=92, 18.1%, and n=163, 32%). ML identified 8 important variables as critical for model construction: RP-ILD, erythrocyte sedimentation rate (ESR), serum albumin (ALB) level, age, C-reactive protein (CRP) level, aspartate aminotransferase (AST) level, lactate dehydrogenase (LDH) level, and the neutrophil-to-lymphocyte ratio (NLR). LR was chosen as the best algorithm for model construction, and the model demonstrated excellent performance, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.866, a sensitivity of 84.8%, and a specificity of 84.4% on the validation data set and an AUC of 0.90, a sensitivity of 85.0%, and a specificity of 83.9% on the training data set. Calibration curves and decision curve analysis (DCA) confirmed the model’s accuracy and clinical applicability. Moreover, the model showed strong predictive performance in the external validation cohorts (cohort 1: AUC=0.836, 95% CI 0.754-0.916; cohort 2: AUC=0.915, 95% CI 0.871-0.959), indicating good generalizability. This model was integrated into a web-based tool to predict the 3-month mortality for patients with anti-MDA5+DM-ILD. Conclusions: We successfully developed a robust clinical prediction model and an accompanying web tool to estimate the 3-month mortality risk for patients with anti-MDA5+DM-ILD.

Objective. The aim of this study was to evaluate the diagnostic and prognostic value of red blood cell distribution width (RDW) in patients with connective tissue disease-associated interstitial lung disease (CTD-ILD). Methods. We retrospectively reviewed 213 CTD-ILD patients and 97 CTD patients without ILD from February 2017 to February 2020. Hospital and office records were used as data sources. CTD-ILD patients were followed up. Results. Patients with CTD-ILD had significantly higher RDW than those with CTD without ILD ( ). The area under the receiver operating characteristic curve (AUROC) of RDW for discriminating CTD-ILD from CTD without ILD was 0.64 (95% CI: 0.57-0.70, ). The cutoff value of RDW for discriminating CTD-ILD from CTD without ILD was 13.95% with their corresponding specificity (55.9%) and sensitivity (70.1%). Correlation analyses showed that the increased RDW was significantly correlated with decreased DLCO%predicted ( , ). Cox multiple regression analysis indicated that RDW ( , ) was an independent factor in the survival of CTD-ILD. The best cutoff value of RDW to predict the survival of patients with CTD-ILD was 14.05% ( , 95% CI: 0.72-0.84, ). The log-rank test showed a significant difference in survival between the two groups ( and ). Conclusion. RDW was higher in CTD-ILD patients and had a negative correlation with DLCO%predicted. RDW may be an important serum biomarker for severity and prognosis of patients with CTD-ILD.

Objective. Several serum markers were reported to reflect the severity of pulmonary alveolar proteinosis (PAP). The aim of this study is to investigate a reliable and facile marker to access and monitor the clinical course of PAP in a large cohort.Methods. PAP patients from January 2010 to June 2018 were enrolled. Hospital records were used as data sources. The levels of various serum indicators were detected. We evaluated the correlation between pulmonary function test results and clinical variables.Results. Diffusion capacity for carbon monoxide (DLCO) level was positively correlated with the level of high-density lipoprotein cholesterol (HDL-C) (P<0.05) in 122 patients of PAP at baseline. The levels of HDL-C and DLCO significantly increased while carcinoembryonic antigen (CEA), CYFRA21-1, neuron-specific enolase (NSE), and lactic dehydrogenase (LDH) levels decreased six months after granulocyte-macrophage colony-stimulating factor (GM-CSF) inhalation therapy between 14 patients with PAP. Nevertheless, the increased DLCO was significantly correlated with decreased CEA (r=‐0.579,P=0.031) and CYFRA 21-1 (r=‐0.632,P=0.015). In 10 PAP patients without GM-CSF inhalation therapy, HDL-C and DLCO significantly decreased while NSE and LDH levels increased after six months of follow-up. The decreased DLCO was significantly correlated with increased LDH (r=‐0.694,P=0.026).Conclusions. Serum CEA, CYFRA21-1, and LDH are valuable serum markers for the evaluation of disease activity of PAP and may predict the response to treatment of PAP.