Pretreatment mortality risk prediction model in patients with polymyositis/dermatomyositis-associated interstitial lung disease.

OBJECTIVES: Risk prediction for patients with polymyositis/dermatomyositis-associated interstitial lung disease (PM/DM-ILD) is challenging due to heterogeneity in the disease course. We aimed to develop a mortality risk prediction model for PM/DM-ILD. METHODS: This prognostic study analysed patients with PM/DM-ILD admitted to Nanjing Drum Hospital from 2016 to 2021. The primary outcome was mortality within 1 year. We used a least absolute shrinkage and selection operator (LASSO) logistic regression model to identify predictive laboratory indicators. These indicators were used to create a laboratory risk score, and we developed a mortality risk prediction model by incorporating clinical factors. The evaluation of model performance encompassed discrimination, calibration, clinical utility and practical application for risk prediction and prognosis. RESULTS: Overall, 418 patients with PM/DM-ILD were enrolled and randomly divided into development (n=282) and validation (n=136) cohorts. LASSO logistic regression identified four optimal features in the development cohort, forming a laboratory risk score: C reactive protein, lactate dehydrogenase, CD3+CD4+ T cell counts and PO2/FiO2. The final prediction model integrated age, arthralgia, anti-melanoma differentiation-associated gene 5 antibody status, high-resolution CT pattern and the laboratory risk score. The prediction model exhibited robust discrimination (area under the receiver operating characteristic: 0.869, 95% CI 0.811 to 0.910), excellent calibration and valuable clinical utility. Patients were categorised into three risk groups with distinct mortality rates. The internal validation, sensitivity analyses and comparative assessments against previous models further confirmed the robustness of the prediction model. CONCLUSIONS: We developed and validated an evidence-based mortality risk prediction model with simple, readily accessible clinical variables in patients with PM/DM-ILD, which may inform clinical decision-making.

Novel 3D-based deep learning for classification of acute exacerbation of idiopathic pulmonary fibrosis using high-resolution CT.

PURPOSE: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is the primary cause of death in patients with IPF, characterised by diffuse, bilateral ground-glass opacification on high-resolution CT (HRCT). This study proposes a three-dimensional (3D)-based deep learning algorithm for classifying AE-IPF using HRCT images. MATERIALS AND METHODS: A novel 3D-based deep learning algorithm, SlowFast, was developed by applying a database of 306 HRCT scans obtained from two centres. The scans were divided into four separate subsets (training set, n=105; internal validation set, n=26; temporal test set 1, n=79; and geographical test set 2, n=96). The final training data set consisted of 1050 samples with 33 600 images for algorithm training. Algorithm performance was evaluated using accuracy, sensitivity, specificity, positive predictive value, negative predictive value, receiver operating characteristic (ROC) curve and weighted κ coefficient. RESULTS: The accuracy of the algorithm in classifying AE-IPF on the test sets 1 and 2 was 93.9% and 86.5%, respectively. Interobserver agreements between the algorithm and the majority opinion of the radiologists were good (κw=0.90 for test set 1 and κw=0.73 for test set 2, respectively). The ROC accuracy of the algorithm for classifying AE-IPF on the test sets 1 and 2 was 0.96 and 0.92, respectively. The algorithm performance was superior to visual analysis in accurately diagnosing radiological findings. Furthermore, the algorithm's categorisation was a significant predictor of IPF progression. CONCLUSIONS: The deep learning algorithm provides high auxiliary diagnostic efficiency in patients with AE-IPF and may serve as a useful clinical aid for diagnosis.

Elevated serum mitochondrial DNA levels were associated with the progression and mortality in idiopathic pulmonary fibrosis.

Circulating mitochondrial DNA (mtDNA) was implicated in idiopathic pulmonary fibrosis (IPF), but the association between circulating mtDNA levels with clinical parameters in IPF was unclear. In this study, we investigate the relationship between serum mtDNA levels with the progression and mortality of IPF. Eighty-three patients with clinical diagnoses of IPF and fifty-three healthy controls were enrolled. Clinical data were collected and IPF patients were classified as stable disease (SD) and progressive disease (PD) based on the diagnostic criteria. Serum mtDNA levels were measured by real-time quantitative PCR and were compared between the two groups. Associations of the mtDNA levels with pulmonary function data and clinical parameters were assessed. Cox regression was performed to access the association between serum mtDNA levels with mortality in IPF. The serum mtDNA levels were significantly higher in IPF patients compared to those in healthy controls (P < 0.001), and further higher in patients with PD than those with SD (P < 0.001). Serum mtDNA levels were significantly inverse correlated with carbon monoxide diffusing capacity percent predicted (DLCO% predicted) (P = 0.030) and serum albumin levels (P = 0.008). During follow-up, 36 patients (43.4 %) died with a median survival of 46.00 (IQR: 25.00-69.75) months. Multivariate analysis showed that higher serum mtDNA levels were a significant predictor of mortality in IPF. In conclusion, elevated serum mtDNA levels were associated with the progression and mortality of IPF, which provided new insights that mitochondrial metabolism might have a potential role in the pathogenesis of IPF.

Alveolar macrophages in pulmonary alveolar proteinosis: origin, function, and therapeutic strategies.

Pulmonary alveolar proteinosis (PAP) is a rare pulmonary disorder that is characterized by the abnormal accumulation of surfactant within the alveoli. Alveolar macrophages (AMs) have been identified as playing a pivotal role in the pathogenesis of PAP. In most of PAP cases, the disease is triggered by impaired cholesterol clearance in AMs that depend on granulocyte-macrophage colony-stimulating factor (GM-CSF), resulting in defective alveolar surfactant clearance and disruption of pulmonary homeostasis. Currently, novel pathogenesis-based therapies are being developed that target the GM-CSF signaling, cholesterol homeostasis, and immune modulation of AMs. In this review, we summarize the origin and functional role of AMs in PAP, as well as the latest therapeutic strategies aimed at addressing this disease. Our goal is to provide new perspectives and insights into the pathogenesis of PAP, and thereby identify promising new treatments for this disease.

Updated severity and prognosis score of pulmonary alveolar proteinosis: A multi-center cohort study in China.

Background: The high-resolution computed tomography (HRCT) score is an important component of the severity and prognosis score of pulmonary alveolar proteinosis (SPSP). However, the HRCT score in SPSP only considers the extent of opacity, which is insufficient. Methods: We retrospectively evaluated HRCT scores for 231 patients with autoimmune pulmonary alveolar proteinosis (APAP) from three centers of the China Alliance for Rare Diseases. The SPSPII was created based on the overall density and extent, incorporating the SPSP. The severity of APAP patients was assessed using disease severity scores (DSS), SPSP, and SPSPII to determine the strengths and weaknesses of the different assessment methods. We then prospectively applied the SPSPII to patients before treatment, and the curative effect was assessed after 3 months. Results: The HRCT overall density and extent scores in our retrospective analysis were higher than the extent scores in all patients and every original extent score severity group, as well as higher related to arterial partial oxygen pressure (PaO2) than extent scores. The mild patients accounted for 61.9% based on DSS 1-2, 20.3% based on SPSP 1-3, and 20.8% based on SPSPII 1-3. Based on SPSP or SPSPII, the number of severe patients deteriorating was higher in the mild and moderate groups. When applied prospectively, arterial PaO2 differed between any two SPSPII severity groups. The alveolar-arterial gradient in PaO2 (P[A-a]O2), % predicted carbon monoxide diffusing capacity of the lung (DLCO), and HRCT score were higher in the severe group than in the mild and moderate groups. After diagnosis, mild patients received symptomatic treatment, moderate patients received pure whole lung lavage (WLL) or granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy, and severe patients received WLL and GM-CSF therapy. Importantly, the SPSPII in mild and severe groups were lower than baseline after 3 months. Conclusion: The HRCT density and extent scores of patients with APAP were better than the extent score. The SPSPII score system based on smoking status, symptoms, PaO2, predicted DLCO, and overall HRCT score was better than DSS and SPSP for assessing the severity and efficacy and predicting the prognosis. Trial registration: ClinicalTrial.gov, identifier: NCT04516577.

Increased serum levels of sCD40L were associated with rapidly progressive interstitial lung disease in idiopathic inflammatory myopathies.

OBJECTIVES: Whether coagulopathy exists in development of idiopathic inflammatory myopathies associated rapidly progressive interstitial lung disease (IIMs-RPILD) is unclear. In this study, we aimed to investigate soluble CD40 ligand and D-dimer levels in RPILD patients. METHODS: Patients with IIMs-ILD were enrolled and classified as RPILD and stable-ILD group. Clinical data, laboratory examinations including coagulation-associated parameters and the myositis antibodies status, chest high-resolution computed tomography (HRCT) findings and treatment regimens were collected and serum levels of sCD40L were detected by ELISA. Univariable and adjusted multivariable cox regression were performed to identify risk factors for 6-month mortality, and further to select predictors for establishing predictive model for RPILD. RESULTS: Eighty patients with IIMs-ILD were enrolled and 34 of them were diagnosed as RPILD while 46 as stable-ILD. Multivariable cox regression showed that albumin<32.4 g/L and sCD40L<1658.55 pg/ml were independent risk factors of short-term mortality in RPILD. A SMAD model consisting of serum sCD40L>1054 pg/ml, anti-MDA5 positivity, albumin<32.4 g/L and D-dimer>0.865 mg/L were generated. The odds for RPILD with SMAD score of 0, 1, 2, 3 and 4 were 0, 26.9%, 66.7%, 91.7% and 100%. The 6-month survival stratified by mild (SMAD score 0), moderate (SMAD score 1 and 2) and severe group (SMAD score 3 and 4) were 100%, 79.5% and 20%, respectively. CONCLUSIONS: We established a predictive model for IIMs-RPILD, which provided a clue that coagulopathy might exist in IIMs-RPILD and could help to better treat patients with RPILD. This model awaits further validations.

An observational study of clinical recurrence in patients with interstitial lung disease related to the antisynthetase syndrome.

OBJECTIVE: To describe the clinical characteristics and risk factors of clinical recurrence in interstitial lung disease related to antisynthetase syndrome (ARS-ILD). METHODS: Patients diagnosed as ARS-ILD in Nanjing Drum Tower Hospital between January 2015 and November 2020 were retrospectively analyzed. Clinical information and treatment course were reviewed. The primary endpoint was the disease recurrence, and the secondary point was mortality. Univariate and multivariable Cox regression analyses were performed to identify risk factors for recurrence. RESULTS: Totally, 132 patients with ARS-ILD received immunomodulation treatment from diagnosis. During follow-ups, sixty-nine patients showed recurrence, with a recurrency rate yielding 52.3%. The median duration from treatment initiation to recurrence was 11 (5-18) months. The median tapering course in the recurrence group was 8 (3-12.5) months, which was significantly shorter than the 16 (10-32) months in the no-recurrence group (p < 0.001). Fifty-eight patients experienced recurrence when the glucocorticoids (GC) dose dropped to 10 (9.375-15) mg/day. Twelve patients discontinued GC with a median treatment course of 11.5 (8-16.75) months, and 11 patients developed recurrence after discontinuing GC for 3 (1-4) months. Twelve patients died, with a mortality rate of 9.1%, and recurrence was not associated with increased mortality. The adjusted multivariate analysis showed that age, increased serum lactate dehydrogenase (LDH) level, relatively shorter tapering duration, and inappropriate GC discontinuation were associated with recurrence. CONCLUSION: Recurrence of ARS-ILD was common during medication intensity reduction. Age, LDH, medication tapering duration, and discontinuation were risk factors for recurrence. Further efforts to reduce recurrence should take into consideration of these factors. Key Points • Recurrence is observed commonly with a recurrency rate 52.3% in patients with interstitial lung disease related to antisynthetase syndrome (ARS-ILD) when glucocorticoids (GC) tapering or discontinuation. • Age, increased serum lactate dehydrogenase (LDH) level, medication tapering duration, and GC discontinuation were identified to be significantly associated with the recurrence of ARS-ILD.

Tumor-intrinsic RGS1 potentiates checkpoint blockade response via ATF3-IFNGR1 axis.

Background: Non-responsiveness is a major barrier in current cancer immune checkpoint blockade therapies, and the mechanism has not been elucidated yet. Therefore, it is necessary to discover the mechanism and biomarkers of tumor immunotherapeutic resistance. Methods: Bioinformatics analysis was performed based on CD8+ T cell infiltration in multiple tumor databases to screen out genes related to anti-tumor immunity. Associations between Regulator of G-protein signaling 1 (RGS1) and IFNγ-STAT1 signaling, and MHCI antigen presentation pathway were examined by RT-qPCR, western blotting, and flow cytometry. The modulatory mechanisms of RGS1 were investigated via CHIP-qPCR and dual-luciferase assay. The clinical and therapeutic implications of RGS1 were comprehensively investigated using tumor cell lines, mouse models, and clinical samples receiving immunotherapy. Results: RGS1 was identified as the highest gene positively correlated with immunogenicity among RGS family. Inhibition of RGS1 in neoplastic cells dampened anti-tumor immune response and elicited resistance to immunotherapy in both renal and lung murine subcutaneous tumors. Mechanistically, RGS1 enhanced the binding of activating transcription factor 3 (ATF3) to the promoter of interferon gamma receptor 1 (IFNGR1), activated STAT1 and the subsequent expression of IFNγ-inducible genes, especially CXCL9 and MHC class I (MHCI), thereby influenced CD8+ T cell infiltration and antigen presentation and processing. Clinically, lower expression level of RGS1 was associated with resistance of PD1 inhibition therapy and shortened progression-free survival among 21 NSCLC patients receiving immunotherapy. Conclusions: Together, these findings uncover a novel mechanism that elicits immunotherapy resistance and highlight the function of tumor-intrinsic RGS1, which brings new insights for future strategies to sensitize anti-PD1 immunotherapy.

Quantitative chest CT assessment of pulmonary alveolar proteinosis with deep learning: a real-world longitudinal study.

Background: High-resolution computed tomography (HRCT) plays an important role in accessing the severity of pulmonary alveolar proteinosis (PAP). Visual evaluation of changes between two HRCT scans is subjective. This study was conducted to quantitatively evaluate lung burden changes in patients with PAP using HRCT-based automated deep-learning method following 12 months of statin therapy. Methods: In this prospective real-world observational study, patients with PAP who underwent chest HRCT were evaluated from November 28, 2018, to April 12, 2021. Oral statin administration was initiated as therapy for these PAP patients with 12 months of follow-up. HRCT-derived lung ground-glass opacification percentage of the whole lung and 5 lobes and the percentage of different densities of ground glass were automatically quantified with deep-learning software. Longitudinal changes of the HRCT quantitative parameter were also compared. Results: The study enrolled 50 patients with PAP, including 25 mild-moderate PAP cases and 25 severe PAP cases. The percentage of lung ground-glass opacification of the whole lung and 5 lobes and the percentage of different densities of ground glass were significantly different among the 2 different clinical types at baseline (all P values <0.05). Overall, the percentage of whole-lung ground-glass opacification significantly decreased between the baseline HRCT and the HRCT results after 12 months of follow-up (P=0.023; 95% CI: 1.384-18.684). Changes in the total opacification of the whole lung were positively correlated with changes in partial pressure of arterial oxygen (PaO2; r=0.716; P<0.001) and percentage of predicted diffusion capacity for carbon monoxide (DLCO%pred; r=0.664; P<0.001). Conclusions: A quantitative image parameter automatically generated by a deep-learning tool from chest HRCT scans may be used to evaluate the severity of PAP and may help to evaluate and quantify the response to statin therapy.

Assessment of Statin Treatment for Pulmonary Alveolar Proteinosis without Hypercholesterolemia: A 12-Month Prospective, Longitudinal, and Observational Study.

Background: Pulmonary alveolar proteinosis (PAP) is a rare disorder which is characterized by the accumulation of excessive surfactant lipids and proteins in alveolar macrophages and alveoli. Oral statin therapy has been reported to be a novel therapy for PAP with hypercholesterolemia. We aimed to evaluate the safety and efficacy of oral statin therapy for PAP without hypercholesterolemia. Methods: In a prospective real-world observational study, 47 PAP patients without hypercholesterolemia were screened. Oral statin was initiated as therapy for these PAP patients with 12 months of follow-up. Results: Forty PAP patients completed the study. 26 (65%) of 40 PAP patients responded to statin therapy according to the study criteria. Partial pressure of arterial oxygen (PaO2) and percentage of diffusion capacity predicted (DLCO%) significantly increased while disease severity score (DSS) and radiographic abnormalities decreased after 12 months of statin therapy (all p < 0.05). The factors associated with response were higher levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) antibody and baseline total cholesterol/high-density lipoprotein cholesterol (TC/HDL) (p = 0.015 and p = 0.035, respectively). The area under the receiver operating characteristic curve (AUROC) of dose of atorvastatin for predicting the response to statin therapy for PAP was 0.859 (95% CI: 0.738-0.979, p < 0.001). The cutoff dose of atorvastatin was 67.5 mg daily with their corresponding specificity (64.3%) and sensitivity (96.2%). No severe side effects were observed during the study. Conclusions: In PAP patients without hypercholesterolemia, statin therapy resulted in improvements in arterial blood gas (ABG) measurement, pulmonary function, and radiographic assessment.

Prediction model for the pretreatment evaluation of mortality risk in anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis with interstitial lung disease.

Background: Anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis with interstitial lung disease (anti-MDA5 DM-ILD) is a disease with high mortality. We sought to develop an effective and convenient prediction tool to estimate mortality risk in patients with anti-MDA5 DM-ILD and inform clinical decision-making early. Methods: This prognostic study included Asian patients with anti-MDA5 DM-ILD hospitalized at the Nanjing Drum Hospital from December 2016 to December 2020. Candidate laboratory indicators were retrospectively collected. Patients hospitalized from 2016 to 2018 were used as the discovery cohort and applied to identify the optimal predictive features using a least absolute shrinkage and selection operator (LASSO) logistic regression model. A risk score was determined based on these features and used to construct the mortality risk prediction model in combination with clinical characteristics. Results were verified in a temporal validation comprising patients treated between 2019 and 2020. The primary outcome was mortality risk within one year. The secondary outcome was overall survival. The prediction model's performance was assessed in terms of discrimination, calibration, and clinical usefulness. Results: This study included 127 patients, (72 men [56.7%]; median age, 54 years [interquartile range, 48-63 years], split into discovery (n = 87, 70%) and temporal validation (n=37, 30%) cohorts. Five optimal features were selected by LASSO logistic regression in the discovery cohort (n = 87) and used to construct a risk score, including lymphocyte counts, CD3+CD4+ T-cell counts, cytokeratin 19 fragment (CYFRA21-1), oxygenation index, and anti-Ro52 antibody. The retained predictive variables in the final prediction model were age, Heliotrope, fever, and risk score, and the most predictive factor was the risk score. The prediction model showed good discrimination (AUC: 0.915, 95% CI: 0.846-0.957), good calibration (Hosmer-Lemeshow test, P = 0.506; Brier score, 0.12), and fair clinical usefulness in the discovery cohort. The results were verified among patients in the temporal validation cohort (n = 38). We successfully divided patients into three risk groups with very different mortality rates according to the predictive score in both the discovery and validation cohorts (Cochran-Armitage test for trend, P < 0.001). Conclusions: We developed and validated a mortality risk prediction tool with good discrimination and calibration for Asian patients with anti-MDA5 DM-ILD. This tool can offer individualized mortality risk estimation and inform clinical decision-making.

Development of a scoring system with multidimensional markers for fibrosing interstitial lung disease.

Fibrosing interstitial lung disease (ILD) can cause high mortality and sensitive evaluation of fibrosing ILD could be critical. The aim of this study is to develop a scoring system to predict prognosis of fibrosing ILD. 339 patients with fibrosing ILD were enrolled as a derivation cohort. Cox multiple regression analysis indicated that smoking history (HR = 3.826, p = 0.001), age(HR = 1.043, p = 0.015), CEA(HR = 1.059, p = 0.049),CYFRA21-1(HR = 1.177, p = 0.004) and DLCO% predicted (HR = 0.979, p = 0.032) were independent prognostic factors for fibrosing ILD. The clinical scoring system for fibrosing ILD was established based on the clinical variables (age [A], CEA and CYFRA21-1 [C], DLCO% predicted [D], and smoking history [S]; ACDS). The area under the receiver operating characteristic curve (AUROC) of the scoring system for predicting prognosis of fibrosing ILD was 0.90 (95%CI: 0.87-0.94, p < 0.001). The cutoff value was 2.5 with their corresponding specificity (90.7%) and sensitivity (78.8%). To validate the value of ACDS score levels to predict the survival of patients with fibrosing ILD, 98 additional fibrosing ILD patients were included as a validation cohort. The log-rank test showed a significant difference in survival between the two groups(ACDS score < 2.5 and ACDS score ≥ 2.5) in validation cohort. The independent risk factors for mortality in patients with fibrosing ILD are higher CEA, higher CYFRA21-1, smoking history, lower DLCO%predicted at baseline and older age. ACDS is a simple and feasible clinical model for predicting survival of fibrosing ILD.

A Retrospective Analysis of Outcome in Melanoma Differentiation-Associated Gene 5-Related Interstitial Lung Disease Treated with Tofacitinib or Tacrolimus.

OBJECTIVE: The efficacy of tofacitinib (TOF) in the early diagnosis of melanoma differentiation-associated gene 5 (MDA5)-related interstitial lung disease (ILD) has been described. However, whether TOF exposure is associated with a reduced 1-year mortality rate remains undetermined. METHODS: Patients diagnosed with MDA5-ILD receiving TOF or tacrolimus (TAC) treatment were included. A Cox proportional hazards model, which was adjusted for age, sex, smoking history, anti-MDA5 antibody titers, and concurrent use of other steroid-sparing agents, was performed to compare all-cause mortality and to investigate the risk factors predicting 1-year mortality rates in the 2 treatment groups. RESULTS: During the study period, 26 patients were treated with TOF and 35 were treated with TAC. The 6-month (38.5% vs 62.9%; P = 0.03) and 1-year (44.0% vs 65.7%; P = 0.03) mortality rates in the TOF group were significantly lower than those in the TAC group. There were 13 patients diagnosed with rapidly progressive ILD (RP-ILD) in the TOF group and 22 in the TAC group. The majority of deaths occurred in patients with RP-ILD. The 6-month (76.9% vs 95.5%; P = 0.02) and 1-year (84.6% vs 100.0%; P = 0.02) mortality rates of patients with RP-ILD in the TOF group were also lower than those in the TAC group, respectively. The adjusted model showed that TOF exposure was associated with a lower risk for 1-year mortality (hazard ratio 0.44, 95% CI 0.20-0.96; P = 0.04). However, the incidence of adverse events (73.1% vs 74.3%; P > 0.99) and medication discontinuation rates (23.1% vs 14.3%; P = 0.50) in the TOF and TAC groups were similar, respectively. CONCLUSION: Our observational study showed that TOF use might have a potential effect on improving the outcomes of MDA5-ILD. Future clinical trials are needed to assess the long-term efficacy and tolerability of TOF.

Soluble ST2 in serum predicts the prognosis of idiopathic pulmonary fibrosis: a retrospective study.

Background: Idiopathic pulmonary fibrosis (IPF) is a heterogeneous and progressive fibrosing interstitial lung disease with a poor prognosis. However, there are currently no effective biomarker that can reliably predict the prognosis for IPF in clinic. The serum level of soluble suppression of tumorigenicity-2 (sST2), which is involved in the immune response, has proven to be a prognostic predictor for various diseases. Previous studies have confirmed that the immune dysfunction plays an important role in the pathogenesis of IPF and the serum sST2 concentrations in patients with IPF are elevated. However, the relationship between sST2 and the prognosis of IPF remains unknown. Methods: A total of 83 patients with IPF and 20 healthy controls from 2016 to 2021 were enrolled and demographic variables, indices of lung function testing as well as the biomarkers including the sST2 were obtained at baseline. During follow-up, the primary endpoint was defined as all-cause death and clinical deterioration. Cox hazard models and Kaplan-Meier method were used to assess the prognostic value of various indices including sST2. Results: Mean duration of follow-up was 29 months, during which 49 patients had an event, and of them, 35 patients died. The sST2 level was higher in the IPF patients compared with the healthy controls. Although the sST2 level did not directly predict all-cause death in the present study, it was proved to be an independent predictor of event-free survival. Multivariate forward stepwise model which was adjusted by age, sex, and body surface area (BSA) showed that the overexpression of sST2 increased the hazard ratio [1.005, 95% confidence interval (CI): 1.001-1.010]. A higher sST2 serum level heralded more deterioration and the poor outcomes. Moreover, the effect of sST2 on the prognosis of IPF may not necessarily involve the development of IPF-related pulmonary hypertension (PH). Conclusions: In our study, the sST2 serum level was significantly elevated and a higher serum level of sST2 predicted more deterioration and poor outcomes in patients with IPF. Thus, sST2 can serve as a valuable prognostic biomarker for the outcome of IPF. However, further multicenter clinical trials of larger sample size are needed in the future.

Elevated Expression of Growth Differentiation Factor-15 Is Associated With Acute Exacerbation of Idiopathic Pulmonary Fibrosis.

Backgrounds: Growth differentiation factor 15 (GDF-15) is a highly divergent member of the TGF-ß superfamily and has been implicated in various biological functions. However, the expression of GDF-15 in patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is unclear. Method: The study included 47 AE-IPF patients, 61 stable IPF (S-IPF) subjects, and 31 healthy controls (HCs). Serum GDF-15 levels and their expression in the lung were measured. The correlation between serum GDF-15 and other clinical parameters and the risk factors for AE occurrence and the survival of IPF patients were analyzed. Results: Serum GDF-15 levels were significantly elevated in AE-IPF patients (1279.22 ± 540.02 pg/ml) as compared with HCs (891.30 ± 479.90 pg/ml) or S-IPF subjects (107.82 ± 14.21 pg/ml) (both p < 0.001). The protein and mRNA expressions of GDF-15 in the lung of AE-IPF patients were significantly increased as compared with S-IPF cases (p = 0.007 and p = 0.026, respectively). The serum GDF-15 level was correlated with the clinical variables of inflammation, metabolism, and disease severity in IPF subjects (all p < 0.05). The GDF-15 serum concentration was significantly higher in decedents than in survivors (p = 0.005). A serum GDF-15 level above 989.3 pg/ml was a risk factor for AE occurrence (p = 0.04), and the level above 1,075.76 pg/ml was an independent predictor for survival in IPF cases (p = 0.007). Conclusions: The GDF-15 level was significantly elevated in subjects with AE-IPF. GDF-15 could be a promising biomarker for AE occurrence and survival in IPF patients.

Human epididymis protein 4 is associated with severity and poor prognosis of connective tissue disease-associated interstitial lung disease with usual interstitial pneumonia pattern.

BACKGROUND: Overexpression of human epididymis protein 4 (HE4) was previously described in idiopathic pulmonary fibrosis (IPF), but whether serum HE4 can be considered as a potential biomarker in connective tissue disease-associated interstitial lung disease (CTD-ILD) with usual interstitial pneumonia (UIP) pattern was still unknown. METHOD: A total of 55 CTD-ILD patients with UIP pattern (UIP-CTD) and 52 healthy controls were enrolled in this study. The serum levels of HE4 and Krebs von den Lungen-6 (KL-6) were evaluated in both cohorts. In addition, immunohistochemistry analysis for HE4 was performed on the lung sections of 6 patients with rheumatoid arthritis-associated UIP (UIP-RA) and 6 patients with early-stage lung cancer as normal control. RESULTS: The levels of serum HE4 and KL-6 were higher in patients with UIP-CTD than in healthy controls (292.3 pmol/L versus 79.5 pmol/L for HE4, p < 0.001; 1091.0 IU/mL versus 171.5 IU/mL for KL-6, p < 0.001). Significant correlations between serum HE4 levels and percentpredicted forced vital capacity (FVC%) (r = -0.425, p = 0.004), percent predicted diffusing capacity of the lung for carbon monoxide (DLCO%) (r = -0.447, p = 0.003), and Gender-Age-Physiology (GAP) index (r = 0.494, p < 0.001) were observed in UIP-CTD patients. In immunohistochemistry analysis, elevated expression of HE4 in bronchiolar epithelium and mesenchyme was observed in patients with UIP-RA compared with controls. The serum levels of HE4 (≥277.5 pmol/L) and GAP index were related to an increased risk of mortality (HR = 3.884, p = 0.034; HR = 1.480, p = 0.028, respectively). CONCLUSION: The expression of HE4 in serum and lung specimens was significantly elevated in UIP-CTD patients. Moreover, serum HE4 may be utilized as a biomarker to evaluate the severity of disease and predict the prognosis of UIP-CTD patients.

Anti-Ro52 antibodies are associated with the prognosis of adult idiopathic inflammatory myopathy-associated interstitial lung disease.

OBJECTIVES: In the present study, we aimed to assess the prevalence and clinical significance of anti-Ro52 antibodies in a cohort of patients with idiopathic inflammatory myopathy-associated interstitial lung disease (IIM-ILD) with different myositis-specific autoantibodies (MSAs). METHODS: A cohort of 267 IIM-ILD patients, including 62 patients with PM, 126 patients with DM and 79 patients with clinically amyopathic DM (CADM) were retrospectively analysed in this study. Clinical and laboratory findings, pulmonary function tests (PFTs), HRCT patterns and treatment information were compared between patients with and without anti-Ro52 antibodies. The association between prognosis and anti-Ro52 antibodies was also evaluated based on different MSA subgroups. RESULTS: Anti-Ro52 antibodies were more frequent in patients with anti-MDA5 (62.1%, P < 0.01) and anti-Jo1 (64.9%, P < 0.01) antibodies than in those with other MSAs. The proportion of patients with anti-Jo1 antibodies was higher in the anti-Ro52 antibody-positive group than in the anti-Ro52 antibody-negative group. Patients with anti-Ro52 antibodies were more likely to exhibit the Gottron sign than the anti-Ro52 antibody-negative group (P < 0.001). Furthermore, it was a predictive factor for rapid progression interstitial lung disease (RP-ILD) (P = 0.001) and was also associated with a higher mortality rate (log-rank test, P = 0.001). Furthermore, RP-ILD was more frequently exhibited in anti-MDA5- and anti-Ro52-positive patients. Moreover, anti-Ro52 antibody positivity was closely associated with a higher mortality rate in anti-MDA5-ILD patients (log-rank test, P < 0.05). CONCLUSIONS: Anti-Ro52 antibodies were highly prevalent in patients with anti-MDA5 and anti-Jo1 antibodies. Within all patients with IIM-ILD, those with anti-Ro52 autoantibodies had a higher frequency of RP-ILD and a poorer prognosis, especially in the anti-MDA5 antibody subgroup.

Progressive lymphocytosis in familial hemophagocytic lymphohistiocytosis with lymphocytic interstitial pneumonia: a case report.

Familial hemophagocytic lymphohistiocytosis (FHL) is a genetically heterogeneous disorder which is less typical in adults than pediatric patients. In this study, we reported a rare case of adult-onset FHL3 with progressive lymphocytosis and lymphocytic interstitial pneumonia (LIP). A 20-year old female was admitted to our institution for persistent cough with fever. A chest high-resolution computed tomography (HRCT) scan showed diffuse bilateral ground glass opacities (GGO). A lung biopsy revealed infiltration of lymphocyte in the pulmonary interstitium. The patient was treated with corticosteroids and immunosuppressants, followed by significant clinical improvement although lymphocytosis still persisted. The definitive diagnosis of FHL was based on whole genome sequencing by which heterozygous mutations in UNC13D gene were identified. Lymphocytosis may be a remarkable feature of some patients with FHL. Performing gene sequencing is important to improve the recognition of FHL to avoid misdiagnosis.

Association of Red Blood Cell Distribution Width Levels with Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-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 (p < 0.001). 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, p < 0.001). 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 (r = -0.211, p = 0.002). Cox multiple regression analysis indicated that RDW (HR = 1.495, p < 0.001) 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% (AUC = 0.78, 95% CI: 0.72-0.84, p < 0.001). The log-rank test showed a significant difference in survival between the two groups (RDW > 14.05% and RDW < 14.05%). 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.

Protective function of interleukin-22 in pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive scarring disease with unknown etiology. The evidence of a pathogenic role for transforming growth factor-beta (TGF-ß) in the development and progression of IPF is overwhelming. In the present study, we investigated the role of interleukin-22 (IL-22) in the pathogenesis of IPF by regulating the TGF-ß pathway. We measured parameters and tissue samples from a clinical cohort of IPF. IL-22R knock out (IL-22RA1-/- ) and IL-22 supplementation mouse models were used to determine if IL-22 is protective in vivo. For the mechanistic study, we tested A549, primary mouse type II alveolar epithelial cell, human embryonic lung fibroblast, and primary fibroblast for their responses to IL-22 and/or TGF-ß1. In a clinical cohort, the expression level of IL-22 in the peripheral blood and lung tissues of IPF patients was lower than healthy controls, and the lower IL-22 expression was associated with poorer pulmonary function. IL-22R-/- mice demonstrated exacerbated inflammation and fibrosis. Reciprocally, IL-22 augmentation by intranasal instillation of recombinant IL-22 repressed inflammation and fibrotic phenotype. In vitro, IL-22 treatment repressed TGF-ß1 induced gene markers representing epithelial-mesenchymal-transition and fibroblast-myofibroblast-transition, likely via the inhibition of TGF-ß receptor expression and subsequent Smad2/3 activation. IL-22 appears to be protective against pulmonary fibrosis by inhibiting TGF-ß1 signaling, and IL-22 augmentation may be a promising approach to treat IPF.