Differences in the risk of immune-related pneumonitis between PD-1 and PD-L1 inhibitors: a meta-analysis according to the new mirror-principle and PRISMA guidelines.

PURPOSE: To compare the risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors, the meta-analysis was designed. METHOD: The difference in risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors was assessed by two different meta-analysis methods, the Mirror-pairing and the PRISMA guidelines. RESULTS: A total of eighty-eight reports were used for meta-analysis, while thirty-two studies were used for the Mirror-pairing. Both PD-1 and PD-L1 inhibitors (used alone or combined with chemotherapy) increased the risk of developing immune-related pneumonitis (P < 0.00001; P < 0.00001). Based on indirect analyses results (subgroup analyses), the risk of PD-L1-induced pneumonitis was weaker than that of PD-1 inhibitors when the control group was chemotherapy (OR = 3.33 vs. 5.43) or placebo (OR = 2.53 vs. 3.19), while no obvious significant differences were found (P = 0.17; P = 0.53). For the Mirror-pairing-based meta-analysis, the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors (OR = 1.46, 95%CI [1.08, 1.98], I2 = 0%, Z = 2.47 (P = 0.01)). However, this difference was not significant, when they were combined with chemotherapy (OR = 1.05, 95%CI [0.68, 1.60], I2 = 38%, Z = 0.21 (P = 0.84)). CONCLUSION: Both PD-1 and PD-L1 inhibitors increased the risk of immune-related pneumonitis, while the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors.

Hypersensitivity Pneumonitis on Thin-Section Chest CT Scans: Diagnostic Performance of the ATS/JRS/ALAT versus ACCP Imaging Guidelines.

Purpose To compare the diagnostic performance of the American Thoracic Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax (ATS/JRS/ALAT) versus the American College of Chest Physicians (ACCP) imaging classifications for hypersensitivity pneumonitis (HP). Materials and Methods Patients in the institutional review board-approved Interstitial Lung Disease (ILD) registry referred for multidisciplinary discussion (MDD) at the authors' institution (January 1, 2006-April 1, 2021) were included in this retrospective study when ILD was diagnosed at MDD. MDD diagnoses included HP, connective tissue disease-ILD, and idiopathic pulmonary fibrosis. Retrospective review of thin-section CT images was performed in consensus by two cardiothoracic radiologists blinded to the diagnosis. Diagnostic patterns were determined for thin-section CT images using both classifications. Discordance rates were determined. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were assessed using MDD diagnosis as the reference standard. Results A total of 297 patients were included in the study: 200 (67%) with HP, 49 (16%) with connective tissue disease-ILD, and 48 (16%) with idiopathic pulmonary fibrosis at MDD. The discordance rate between the two classifications was 21%. Assuming low HP prevalence (10%), ATS/JRS/ALAT classification outperformed ACCP classification, with greater accuracy (92.3% vs 87.6%) and greater positive predictive value (60.7% vs 42.9%). Assuming high prevalence (50%), accuracy and negative predictive value were superior using ACCP classification (81.7% vs 79.7% and 77.7% vs 72.6%, respectively), and positive predictive value was superior using ATS/JRS/ALAT classification (93.3% vs 87.1%). Conclusion Accuracy of the ATS/JRS/ALAT and ACCP HP classifications was greater in settings with low and high HP prevalence, respectively. Diagnostic performance of both classifications was discordant in a minority of cases. Keywords: CT, Thorax, Hypersensitivity Pneumonitis, Interstitial Lung Disease Supplemental material is available for this article. © RSNA, 2024.

The prognostic impact of severe grade immune checkpoint inhibitor related pneumonitis in non-small cell lung cancer patients.

Objective: To compare the prognostic differences between non-small cell lung cancer (NSCLC) patients with mild and severe checkpoint inhibitor-associated pneumonitis (CIP), and explore the causes of death and prognostic risk factors in NSCLC patients with severe CIP. Methods: A retrospective study of a cohort of 116 patients with unresectable stage III or IV NSCLC with any grade CIP from April 2016 to August 2022 were conducted. To analyze the clinical characteristics of patients with different CIP grades, patients were divided into mild CIP group (grade 1-2, n=49) and severe CIP group (grade 3-5, n=67) according to the grade of CIP. To explore the OS-related risk factors in the severe CIP group, the patients were divided into a good prognosis (GP) group (≥ median OS, n=30) and a poor prognosis (PP) group (< median OS, n=37) based on whether their overall survival (OS) were greater than median OS. Baseline clinical and laboratory data were collected for analysis. Results: The median OS of all NSCLC patients combined with CIP was 11.4 months (95%CI, 8.070-16.100), The median OS for mild CIP and severe CIP was 22.1 months and 4.4 months respectively (HR=3.076, 95%CI, 1.904-4.970, P<0.0001). The results showed that the most common cause of death among severe CIP patients in the PP group was CIP and the most common cause in the GP group was tumor. The univariate regression analysis showed that suspension of antitumor therapy was a risk factor for poor prognosis (OR=3.598, 95%CI, 1.307-9.905, p=0.013). The multivariate logistic regression analysis showed that suspension of anti-tumor therapy (OR=4.24, 95%CI, 1.067-16.915, p=0.040) and elevated KL-6 (OR=1.002, 95%CI, 1.001-1.002, p<0.001) were independent risk factors for poor prognosis. Conclusion: In conclusion, patients with severe CIP had a poor prognosis, especially those with elevated KL-6, and the main cause of death is immune checkpoint inhibitor-associated pneumonitis complicated with infection. In addition, anti-tumor therapy for severe CIP patients should be resumed in time and should not be delayed for too long.

Lymphocyte-Directed Immunomodulation Remits Thymoma-Associated Autoimmune Pneumonitis.

BACKGROUND: Thymoma presents with several autoimmune manifestations and is associated with secondary autoimmune regulator (AIRE) deficiency. Pneumonitis has recently been described as an autoimmune manifestation associated with thymoma presenting with similar clinical, radiographic, histological, and autoantibody features as seen in patients with inherited AIRE deficiency who suffer from Autoimmune PolyEndocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) syndrome. OBJECTIVES: To treat two patients with biopsy-proven thymoma-associated pneumonitis with lymphocyte-directed immunomodulation. METHODS: Two patients with thymoma were enrolled on IRB-approved protocols at the NIH Clinical Center. We performed history and physical examination; laboratory, radiographic, histologic and pulmonary function evaluations; and measurement of the lung-directed autoantibodies KCNRG and BPIFB1 prior to and at 1- and 6-months following initiation of lymphocyte-directed immunomodulation with azathioprine with or without rituximab. RESULTS: Combination T- and B-lymphocyte-directed immunomodulation resulted in improvement of clinical, functional, and radiographic parameters at 6-month follow-up evaluations in both patients with sustained remission up to 12-36 months following treatment initiation. CONCLUSION: Lymphocyte-directed immunomodulation remitted autoimmune pneumonitis in two patients with thymoma.

Severe lupus pneumonitis: A case of life-saving multimodal therapy with rituximab and corticosteroids.

Severe lupus pneumonitis is a rare and life-threatening complication of systemic lupus erythematosus (SLE), characterized by its rapid progression and high mortality rate. This case report describes the clinical trajectory and therapeutic management of a young Aboriginal female with established lupus nephritis who developed severe lupus pneumonitis. Despite her stable renal condition under long-term immunosuppressive treatment, she experienced acute respiratory distress, leading to her admission to the intensive care unit and subsequent mechanical ventilation. The diagnostic process was complicated by the difficulty in obtaining tissue biopsies, necessitating reliance on clinical judgement and radiological evidence to formulate a diagnosis. The patient was treated with pulsed intravenous methylprednisolone followed by rituximab infusions, resulting in significant clinical and radiological improvement. This case highlights the importance of early and intensive immunosuppressive therapy in the management of severe lupus pneumonitis and underscores the utility of a multidisciplinary approach in overcoming diagnostic ambiguities. Furthermore, it contributes to the growing body of evidence supporting the efficacy of rituximab in severe lupus pneumonitis cases, offering insights into potential therapeutic avenues when conventional management strategies are inadequate or unsuitable.

Acute hypoxic respiratory failure due to Lenalidomide-induced interstitial pneumonitis in a patient with multiple myeloma.

BACKGROUND: Patients with multiple myeloma are immunosuppressed due to both the disease itself and immunosuppressive therapies. Thus, when presenting with respiratory failure and pulmonary opacities, pneumonia must be considered. However, while rare, immunomodulating medications used in the treatment of multiple myeloma can also cause potentially life-threatening respiratory failure, a distinction which has important treatment implications. CASE PRESENTATION: An 80-year-old male with recently diagnosed multiple myeloma undergoing treatment with lenalidomide and daratumumab presented with acute, rapidly progressive hypoxic respiratory failure ultimately requiring intubation and mechanical ventilatory support. Imaging revealed bilateral pulmonary opacities, however infectious workup was negative, and he was ultimately diagnosed with lenalidomide-induced interstitial pneumonitis, a rare but serious adverse effect of this medication. He was treated with drug discontinuation and methylprednisolone, and quickly recovered. CONCLUSION: Lenalidomide is an immunomodulating medication used in the treatment of multiple myeloma, and is associated with rare but serious cases of drug-induced interstitial pneumonitis. Thus, if a patient receiving lenalidomide develops shortness of breath and/or hypoxia, drug-induced pneumonitis must be on the differential. Permanent drug discontinuation with or without corticosteroids is the mainstay of treatment, and patients are often able to fully recover, underscoring the need for early recognition of this condition.

[Smoking-related interstitial lung disease : Radiological findings, histopathological correlations, and clinical observations]. / Raucherassoziierte interstitielle Lungenerkrankungen : Radiologisches Erscheinungsbild, histopathologische Korrelation und klinische Aspekte.

CLINICAL/METHODOLOGICAL ISSUE: Identifying smoking-related interstitial lung diseases (SRILD) in smokers is challenging, as clinical manifestations can be nonspecific, and there is a variety of SRILD entities that not only interconnect but can also overlap. RADIOLOGICAL STANDARD PROCEDURES: In diagnosing SRILD, imaging techniques such as high-resolution computed tomography (HRCT) allow the identification of characteristic features, serving as crucial pieces of the puzzle for definitive differentiation. PERFORMANCE: Studies have demonstrated that HRCT exhibits a sensitivity of approximately 80-90% in identifying SRILD, with a specificity around 70-80%. The conclusive diagnosis often requires a correlation between histopathological findings and clinical observations. PRACTICAL RECOMMENDATIONS: Regular monitoring of smokers, especially when experiencing symptoms like shortness of breath and cough, coupled with a comprehensive diagnosis of SRILD, is crucial for accurate identification and individualized therapy.

Remission of hypersensitivity pneumonitis after allogeneic hematopoietic stem cell transplantation.

A 50-year-old man was diagnosed with hypersensitivity pneumonitis caused by the environment of his bar owing to worsening symptoms, laboratory test results, and computed tomography images after an environmental inhalation challenge test. His hypersensitivity pneumonitis exacerbated despite receiving prednisolone 20 mg/day. The patient underwent allogeneic hematopoietic stem cell transplantation (HSCT) from a human leukocyte antigen-matched unrelated donor for myelodysplastic syndrome. No exacerbation of hypersensitivity pneumonitis was observed after HSCT. An environmental inhalation challenge test involving exposure to his bar confirmed the remission of hypersensitivity pneumonitis after HSCT. This case demonstrates that hypersensitivity pneumonitis can be remitted by HSCT.

Multi-omics deep learning for radiation pneumonitis prediction in lung cancer patients underwent volumetric modulated arc therapy.

BACKGROUND AND OBJECTIVE: To evaluate the feasibility and accuracy of radiomics, dosiomics, and deep learning (DL) in predicting Radiation Pneumonitis (RP) in lung cancer patients underwent volumetric modulated arc therapy (VMAT) to improve radiotherapy safety and management. METHODS: Total of 318 and 31 lung cancer patients underwent VMAT from First Affiliated Hospital of Wenzhou Medical University (WMU) and Quzhou Affiliated Hospital of WMU were enrolled for training and external validation, respectively. Models based on radiomics (R), dosiomics (D), and combined radiomics and dosiomics features (R+D) were constructed and validated using three machine learning (ML) methods. DL models trained with CT (DLR), dose distribution (DLD), and combined CT and dose distribution (DL(R+D)) images were constructed. DL features were then extracted from the fully connected layers of the best-performing DL model to combine with features of the ML model with the best performance to construct models of R+DLR, D+DLD, R+D+DL(R+D)) for RP prediction. RESULTS: The R+D model achieved a best area under curve (AUC) of 0.84, 0.73, and 0.73 in the internal validation cohorts with Support Vector Machine (SVM), XGBoost, and Logistic Regression (LR), respectively. The DL(R+D) model achieved a best AUC of 0.89 and 0.86 using ResNet-34 in training and internal validation cohorts, respectively. The R+D+DL(R+D) model achieved a best performance in the external validation cohorts with an AUC, accuracy, sensitivity, and specificity of 0.81(0.62-0.99), 0.81, 0.84, and 0.67, respectively. CONCLUSIONS: The integration of radiomics, dosiomics, and DL features is feasible and accurate for the RP prediction to improve the management of lung cancer patients underwent VMAT.

Investigating risk factors and treatment options for severe, partially steroid responsive, and steroid-refractory checkpoint inhibitor pneumonitis.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have revolutionized cancer care with incredible reductions in mortality. One of the most devastating complications of treatment is ICI-related pneumonitis (ICI-p). Despite this, little is known regarding risk factors for severe pneumonitis and treatment effectiveness of various therapeutic options for steroid-refractory disease. To address this, we conducted a retrospective study on patients with cancer who developed ICI-p. METHODS: We examined consecutive patients who received ICIs and developed ICI-p. Risk factors of interest for severe disease and steroid-refractory ICI-p, including pre-treatment pulmonary function tests (PFTs) and chest imaging, were compared between patients with severe (grades 3-5) and mild (grades 1-2) pneumonitis. The clinical and treatment courses for patients with steroid-refractory ICI-p were recorded. RESULTS: A total of 132 patients developed ICI-p, with 60 patients having mild and 72 with severe disease. We found that lower forced vital capacity percent predicted (66.24 vs 85.05, P = .05), lower total lung capacity percent predicted (85.23 vs 99.71, P = .13), and specific radiographic patterns on pre-treatment chest imaging were predictors of severe disease. Initial corticosteroid dose of less than 1 milligram per kilogram prednisone equivalent (P = .14) was correlated with partially steroid-responsive or steroid-refractory ICI-p. Ten patients had steroid refractory ICI-p, and those who received IVIG alone as the immune suppressant beyond corticosteroids had improved survival (P = 05). CONCLUSIONS: We are the first to identify pre-treatment PFTs and chest imaging abnormalities as risk factors for severe ICI-p. We also found that lower corticosteroid doses were associated with partially steroid-responsive and steroid-refractory ICI-p. Larger, prospective studies are needed to validate our results.

[Normal mouse serum alleviates radiation pneumonitis in mice by inhibiting the focal adhesion signaling pathway].

OBJECTIVE: To evaluate the therapeutic effect of normal mouse serum on radiation pneumonitis in mice and explore the possible mechanism. METHODS: Mouse models of radiation pneumonitis induced by thoracic radiation exposure were given intravenous injections of 100 µL normal mouse serum or normal saline immediately after the exposure followed by injections once every other day for a total of 8 injections. On the 15th day after irradiation, histopathological changes of the lungs of the mice were examined using HE staining, the levels of TNF-α, TGF-ß, IL-1α and IL-6 in the lung tissue and serum were detected using ELISA, and the percentages of lymphocytes in the lung tissue were analyzed with flow cytometry. Highth-roughput sequencing of exosome miRNA was carried out to explore the changes in the signaling pathways. The mRNA expression levels of the immune-related genes were detected by qRT-PCR, and the protein expressions of talin-1, tensin2, FAK, vinculin, α-actinin and paxillin in the focal adhesion signaling pathway were detected with Western blotting. RESULTS: In the mouse models of radiation pneumonitis, injections of normal mouse serum significantly decreased the lung organ coefficient, lowered the levels of TNF-α, TGF-ß, IL-1α and IL-6 in the serum and lung tissues, and ameliorated infiltration of CD45+, CD4+ and Treg lymphocytes in the lung tissue (all P < 0.05). The expression levels of Egfr and Pik3cd genes at both the mRNA and protein levels and the protein expressions of talin-1, tensin2, FAK, vinculin, α?actinin and paxillin were all significantly down-regulated in the mouse models after normal mouse serum treatment. CONCLUSION: Normal mouse serum ameliorates radiation pneumonitis in mice by inhibiting the expressions of key proteins in the Focal adhesion signaling pathway.

A case of pneumomediastinum complicating immunotherapy associated pneumonitis.

We describe the case of an 87-year-old gentleman referred to a metropolitan hospital in Sydney with pneumomediastinum complicating immunotherapy associated pneumonitis and recent bronchoscopic intervention. The contribution of pneumonitis in the setting of interstitial lung disease has been well described to developing pneumomediastinum however this is less clear in the setting of immunotherapy associated pneumonitis and to what extent bronchoscopic intervention compounds this risk.

Lung Clearance Index as a Screening Parameter of Pulmonary Impairment in Patients under Immune Checkpoint Therapy: A Pilot Study.

Background: Immune checkpoint blockade (ICB) has presented a breakthrough in the treatment of malignant tumors and increased the overall survival of patients with various tumor entities. ICB may also cause immune-related adverse events, such as pneumonitis or interstitial lung disease. The lung clearance index (LCI) is a multiple-breath washout technique offering information on lung pathology in addition to conventional spirometry. It measures the degree of pulmonary ventilation inhomogeneity and allows early detection of pulmonary damage, especially that to peripheral airways. Methods: This cross-sectional study compared the lung function of patients with melanoma or metastatic cutaneous squamous cell carcinoma who received programmed cell death 1 (PD-1) and cytotoxic T-Lymphocyte-associated Protein 4 (CTLA-4) antibodies, alone or in combination, to age- and sex-matched controls. Lung function was assessed using spirometry, according to American Thoracic Society and European Respiratory Society standards, the LCI, and a diffusion capacity of carbon monoxide (DLCO) measurement. Results: Sixty-one screened patients and thirty-eight screened controls led to nineteen successfully included pairs. The LCI in the ICB-treated patients was 8.41 ± 1.15 (mean ± SD), which was 0.32 higher compared to 8.07 ± 1.17 in the control group, but the difference was not significant (p = 0.452). The patients receiving their ICB therapy for under five months showed a significantly lower LCI (7.98 ± 0.77) compared to the ICB patients undergoing therapy for over five months (9.63 ± 1.22) at the point of testing (p = 0.014). Spirometric analysis revealed that the forced expiratory volume between 25 and 75% of the forced vital capacity (FEF25-75%) in the ICB-treated patients was significantly reduced (p = 0.047) compared to the control group. DLCO (%predicted and adjusted for hemoglobin) was 94.4 ± 19.7 in the ICB patients and 93.4 ± 21.7 in the control group (p = 0.734). Conclusions: The patients undergoing ICB therapy showed slightly impaired lung function compared to the controls. Longer periods of ICB treatment led to deterioration of the LCI, which may be a sign of a subclinical inflammatory process. The LCI is feasible and may be easily integrated into the clinical daily routine and could contribute to early detection of pulmonary (auto-)inflammation.

Quantitative analysis of interstitial lung abnormalities on computed tomography to predict symptomatic radiation pneumonitis after lung stereotactic body radiotherapy.

BACKGROUND AND PURPOSE: Symptomatic radiation pneumonitis (SRP) is a complication of thoracic stereotactic body radiotherapy (SBRT). As visual assessments pose limitations, artificial intelligence-based quantitative computed tomography image analysis software (AIQCT) may help predict SRP risk. We aimed to evaluate high-resolution computed tomography (HRCT) images with AIQCT to develop a predictive model for SRP. MATERIALS AND METHODS: AIQCT automatically labelled HRCT images of patients treated with SBRT for stage I lung cancer according to lung parenchymal pattern. Quantitative data including the volume and mean dose (Dmean) were obtained for reticulation + honeycombing (Ret + HC), consolidation + ground-glass opacities, bronchi (Br), and normal lungs (NL). After associations between AIQCT's quantified metrics and SRP were investigated, we developed a predictive model using recursive partitioning analysis (RPA) for the training cohort and assessed its reproducibility with the testing cohort. RESULTS: Overall, 26 of 207 patients developed SRP. There were significant between-group differences in the Ret + HC, Br-volume, and NL-Dmean in patients with and without SRP. RPA identified the following risk groups: NL-Dmean ≥ 6.6 Gy (high-risk, n = 8), NL-Dmean < 6.6 Gy and Br-volume ≥ 2.5 % (intermediate-risk, n = 13), and NL-Dmean < 6.6 Gy and Br-volume < 2.5 % (low-risk, n = 133). The incidences of SRP in these groups within the training cohort were 62.5, 38.4, and 7.5 %; and in the testing cohort 50.0, 27.3, and 5.0 %, respectively. CONCLUSION: AIQCT identified CT features associated with SRP. A predictive model for SRP was proposed based on AI-detected Br-volume and the NL-Dmean.

The incidence of drug-induced interstitial lung disease caused by epidermal growth factor receptor tyrosine kinase inhibitors or immune checkpoint inhibitors in patients with non-small cell lung cancer in presence and absence of vascular endothelial growth factor inhibitors: a systematic review.

Interstitial lung disease (ILD) or pneumonitis caused by epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) or immune checkpoint inhibitors (ICI) is a major concern in the treatment of non-small cell lung cancer (NSCLC). Whether the addition of vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) inhibitors can reduce the incidence of drug-induced ILD remains unclear. We conducted a systematic review to assess the incidence of ILD induced by EGFR-TKIs or ICIs in the presence or absence of VEGF/VEGFR inhibitors in relevant randomized trials between January 2009 and October 2023. The primary outcome was the odds ratio for the incidence of ILD in all patients worldwide and Asians. Secondary outcomes were the odds ratios (ORs) of the incidence at grade-3 or higher ILD in all patients worldwide and Asians. We identified 13 randomized studies, one sub-analysis in the EGFR-TKI group, and three randomized studies in the ICI group. In the EGFR-TKI group, the OR of ILD incidence at any grade with VEGF/VEGFR inhibitors was 0.54 (95% CI, 0.32-0.90; p = 0.02), which represented a significantly lower incidence than that without VEGF/VEGFR inhibitors. Contrarily, the OR of ILD incidence at grade ≥ 3 with VEGF/VEGFR inhibitors was 1.00 (95% CI, 0.43-2.36; p = 0.99). In all subjects in the ICI group, the OR of ILD incidence at any grade with VEGF/VEGFR inhibitors was 0.78 (95% CI, 0.51-1.21; p = 0.27). The systematic review demonstrated that the addition of VEGF/VEGFR inhibitors could reduce the incidence of drug-induced ILD at any grade caused by EGFR-TKI in patients with NSCLC but could not reduce that at grade ≥ 3. The ILD induced by ICIs remains undetermined owing to the limited number of randomized trials for which ILD data are available. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=409534, identifier CRD42023409534.

Accuracy of the Infectious Diseases Society of America and British Thoracic Society Criteria for Acute Pneumonia in Differentiating Chemical and Bacterial Complications of Aspiration in Comatose Ventilated Patients Following Drug Poisoning.

Drug poisoning frequently leads to admission to intensive care units, often resulting in aspiration, a potentially life-threatening condition if not properly managed. Aspiration can manifest as either bacterial aspiration pneumonia (BAP) or aspiration pneumonitis (AP), which are challenging to distinguish potentially leading to overprescription of antibiotics and the emergence of multidrug-resistant bacteria. This study aims to assess the accuracy of the Infectious Diseases Society of America (IDSA) and British Thoracic Society (BTS) criteria in differentiating BAP from AP in comatose ventilated patients following drug poisoning. This cross-sectional study included 95 patients admitted for drug poisoning at the Lille University Hospital intensive care department, between 2013 and 2017, requiring mechanical ventilation and receiving antibiotics for aspiration. Patients were categorized as having bacterial complications if tracheal sampling yielded positive culture results, and if they were otherwise considered to have chemical complications. The sensitivity, specificity, positive predictive value, and negative predictive value of IDSA and BTS criteria in identifying patients with bacterial complications were evaluated. Among the patients, 34 (36%) experienced BAP. The IDSA criteria demonstrated a sensitivity of 62% and specificity of 33%, while the BTS criteria showed a sensitivity of 50% and specificity of 38%. Both the IDSA and BTS criteria exhibited poor sensitivity and specificity in identifying microbiologically confirmed pneumonia in comatose ventilated patients following drug poisoning.

Effect of Xe/O2 Inhalation on Hemostasis in Experimental Thromboplastin Pneumonitis.

We studied the effectiveness of Xe/O2 mixture inhalation (30% Xe and 70% O2, 20 min for 5 days) in a model of experimental thromboplastin pneumonitis. Inhalation of the studied mixture decreased the intensity of the inflammatory process in the lung tissue assessed by the temperature response of animals, changed lung weight and lung weight coefficient. At acute stage of pneumonitis, an increase in xenon consumption was recorded due to its retention in the gas exchange zone and a natural decrease in oxygen consumption due to partial alveolar/capillary block. The formation of pneumonitis was accompanied by a pronounced procoagulant shift in the regulation system of the aggregate state of blood. The Xe/O2 inhalations ensured physiologically optimal levels of prothrombin and activated partial thromboplastin time against the background of a moderate decrease in fibrinogen level throughout the experiment. At the same time, the activity of the natural anticoagulant antithrombin III increased from day 5 to day 14.

Single Cell Analysis Reveals Novel Immune Perturbations in Fibrotic Hypersensitivity Pneumonitis.

Rationale: Fibrotic hypersensitivity pneumonitis is a debilitating interstitial lung disease driven by incompletely understood immune mechanisms. Objectives: To elucidate immune aberrations in fibrotic hypersensitivity pneumonitis in single-cell resolution. Methods: Single-cell 5' RNA sequencing was conducted on peripheral blood mononuclear cells and bronchoalveolar lavage cells obtained from 45 patients with fibrotic hypersensitivity pneumonitis, 63 idiopathic pulmonary fibrosis, 4 non-fibrotic hypersensitivity pneumonitis, and 36 healthy controls in the United States and Mexico. Analyses included differential gene expression (Seurat), transcription factor activity imputation (DoRothEA-VIPER), and trajectory analyses (Monocle3/Velocyto-scVelo-CellRank). Measurements and Main Results: Overall, 501,534 peripheral blood mononuclear cells from 110 patients and controls and 88,336 bronchoalveolar lavage cells from 19 patients were profiled. Compared to controls, fibrotic hypersensitivity pneumonitis has elevated classical monocytes (adjusted-p=2.5e-3) and are enriched in CCL3hi/CCL4hi and S100Ahi classical monocytes (adjusted-p<2.2e-16). Trajectory analyses demonstrate that S100Ahi classical monocytes differentiate into SPP1hi lung macrophages associated with fibrosis. Compared to both controls and idiopathic pulmonary fibrosis, fibrotic hypersensitivity pneumonitis patient cells are significantly enriched in GZMhi cytotoxic T cells. These cells exhibit transcription factor activities indicative of TGFß and TNFα/NFκB pathways. These results are publicly available at https://ildimmunecellatlas.org. Conclusions: Single-cell transcriptomics of fibrotic hypersensitivity pneumonitis patients uncovered novel immune perturbations, including previously undescribed increases in GZMhi cytotoxic CD4+ and CD8+ T cells - reflecting this disease's unique inflammatory T-cell driven nature - as well as increased S100Ahi and CCL3hi/CCL4hi classical monocytes also observed in idiopathic pulmonary fibrosis. Both cell populations may guide the development of new biomarkers and therapeutic interventions.

Cell-Based Therapy for Fibrosing Interstitial Lung Diseases, Current Status, and Potential Applications of iPSC-Derived Cells.

Fibrosing interstitial lung diseases (FILDs), e.g., due to idiopathic pulmonary fibrosis (IPF), are chronic progressive diseases with a poor prognosis. The management of these diseases is challenging and focuses mainly on the suppression of progression with anti-fibrotic drugs. Therefore, novel FILD treatments are needed. In recent years, cell-based therapy with various stem cells has been investigated for FILD, and the use of mesenchymal stem cells (MSCs) has been widely reported and clinical studies are also ongoing. Induced pluripotent stem cells (iPSCs) have also been reported to have an anti-fibrotic effect in FILD; however, these have not been as well studied as MSCs in terms of the mechanisms and side effects. While MSCs show a potent anti-fibrotic effect, the possibility of quality differences between donors and a stable supply in the case of donor shortage or reduced proliferative capacity after cell passaging needs to be considered. The application of iPSC-derived cells has the potential to overcome these problems and may lead to consistent quality of the cell product and stable product supply. This review provides an overview of iPSCs and FILD, followed by the current status of cell-based therapy for FILD, and then discusses the possibilities and perspectives of FILD therapy with iPSC-derived cells.