Loss Of Lung Function Research Articles

Kiss1 receptor knockout exacerbates airway hyperresponsiveness and remodeling in a mouse model of allergic asthma

BackgroundIn asthma, sex-steroids signaling is recognized as a critical regulator of disease pathophysiology. However, the paradoxical role of sex-steroids, especially estrogen, suggests that an upstream mechanism or even independent of estrogen plays an important role in regulating asthma pathophysiology. In this context, in our previous studies, we explored kisspeptin (Kp) and its receptor Kiss1R’s signaling in regulating human airway smooth muscle cell remodeling in vitro and airway hyperresponsiveness (AHR) in vivo in a mouse (wild-type, WT) model of asthma. In this study, we evaluated the effect of endogenous Kp in regulating AHR and remodeling using Kiss1R knockout (Kiss1R−/−) mice.MethodsC57BL/6J WT (Kiss1R+/+) and Kiss1R−/− mice, both male and female, were intranasally challenged with mixed-allergen (MA) and/or phosphate-buffered saline (PBS). We used flexiVent analysis to assess airway resistance (Rrs), elastance (Ers), and compliance (Crs). Following this, broncho-alveolar lavage (BAL) was performed for differential leukocyte count (DLC) and cytokine analysis. Histology staining was performed using hematoxylin and eosin (H&E) for morphological analysis and Masson’s Trichrome (MT) for collagen deposition. Additionally, lung sections were processed for immunofluorescence (IF) of Ki-67, α-smooth muscle actin (α-SMA), and tenascin-c.ResultsInterestingly, the loss of Kiss1R exacerbated lung function and airway contractility in mice challenged with MA, with more profound effects in Kiss1R−/− female mice. MA-challenged Kiss1R−/− mice showed a significant increase in immune cell infiltration and proinflammatory cytokine levels. Importantly, the loss of Kiss1R aggravated Th2/Th17 biased cytokines in MA-challenged mice. Furthermore, histology of lung sections from Kiss1R−/− mice showed increased collagen deposition on airway walls and mucin production in airway cells compared to Kiss1R+/+ mice. In addition, immunofluorescence analysis showed loss of Kiss1R significantly aggravated airway remodeling and subsequently AHR.ConclusionsThese findings demonstrate the importance of inherent Kiss1R signaling in regulating airway inflammation, AHR, and remodeling in the pathophysiology of asthma.

Assessing Bronchiectasis Progression in Low-dose Screening for Lung Cancer: Frequency and Predictors.

Bronchiectasis is associated with loss of lung function, substantial use of health care resources, and increased morbidity and mortality in people with cardiopulmonary diseases. We assessed the frequency of progression or new development of bronchiectasis and predictors of progression in participants in low-dose computed tomography (CT) screening programs. We reviewed our prospectively enrolled screening cohort in the Early Lung and Cardiac Action Program cohort of smokers, aged 40 to 90, between 2010 and 2019, and medical records to assess the progression of bronchiectasis after five or more years of follow-up after baseline low-dose CT. Logistic and multivariate-analysis-of-covariance regression analyses were used to examine factors associated with bronchiectasis progression. Among 2182 baseline screening participants, we identified 534 (mean age: 65±9y; 53.6% women) with follow-up screening of 5+ years (median follow-up: 103.2mo). Of the 534 participants, 34 (6.4%) participants had progressed (25/126, 19.8%) or newly developed (9/408, 2.2%) bronchiectasis. Significant predictors of progression (progressed+newly developed) were: age (P=0.03), pack-years of smoking (P=0.004), baseline components of the ELCAP Bronchiectasis Score, including the severity of bronchial dilatation (P=0.01), its extent (P=0.01), bronchial wall thickening (P=0.04), and mucoid impaction (P<0.001). Assuming similar progression rates, ~136 out of 2182 participants are expected to progress on follow-up screening. This study sheds light on bronchiectasis progression and its significant predictors in a low-dose CT screening program. We recommend reporting bronchiectasis as participants who have smoked are at increased risk, and continued assessment over the entire period of participation in the low-dose CT screening program would allow for the identification of possible causes, early warning, and even early treatment.

Gal-1-mediated cytochrome p450 activation promotes fibroblast into myofibroblast differentiation in pulmonary fibrosis

Pulmonary fibrosis (PF) results from excessive extracellular matrix (ECM) deposition and tissue remodeling after activation of fibroblasts into myofibroblasts. Abnormally deposited fibrotic ECM, in turn, promotes fibroblast activation and accelerates loss of lung structure and function. However, the molecular mediators and exact mechanisms by which fibrotic ECM promotes fibroblast activation are unclear. In a bleomycin-induced PF mouse model, we found Galectin-1 (Gal-1) expression was significantly increased in lung tissue, and overexpression of Gal-1 plasmid-transfected fibroblasts were activated into myofibroblasts. Using the decellularization technique to prepare decellularized fibrotic ECM and constructing a 3D in vitro co-culture system with fibroblasts, we found that decellularized fibrotic ECM induced a high expression of Gal-1 and promoted the activation of fibroblasts into myofibroblasts. Therefore, Gal-1 has been identified as a pivotal mediator in PF. Further, we found that decellularized fibrotic ECM delivered mechanical signals to cells through the Gal-1-mediated FAK-Src-P130Cas mechanical signalling pathway, while the CYP450 enzymes (mainly involved in CYP1A1, CYP24A1, CYP3A4, and CYP2D6 isoforms) acted as a chemical signalling pathway to receive mechanical signals transmitted from upstream Gal-1, thereby promoting fibroblast activation. The Gal-1 inhibitor OTX008 or the CYP1A1 inhibitor 7-Hydroxyflavone prevented PF in mice and inhibited the role of fibrotic ECM in promoting fibroblast activation into myofibroblasts, preventing PF. These results reveal novel molecular mechanisms of lung fibrosis formation and identify Gal-1 and its downstream CYP1A1 as potential therapeutic targets for PF disease treatmnts.

Serum Vitamin D Status in Patients with Asthma-COPD Overlap

Introduction: Asthma-COPD overlap shared its risk factors with asthma and COPD, including development in the later decades of life, airway hyper-responsiveness, often tobacco smoke exposure, and progressive loss of lung function. It has been shown that this group of patients might possess vitamin D deficiency. By assessing the level of vitamin D we can identify the deficiency earlier and can give appropriate supplements. Objective: This study was done to assess the serum vitamin D status in patients with Asthma-COPD overlap. Materials and Methods: This cross-sectional study was carried out in the Department of Physiology of Bangabandhu Sheikh Mujib Medical University, Dhaka, from January 2018 to July 2018. Total 47 men subjects age ranged between 40-70 years were involved in this study. Among them 23 (twenty three) men (40-70 years) were involved as study group (Group II) and 24 (twenty four) men (40-70 years) were taken as control group (Group I). Results: The results were expressed as mean with standard error (mean±SEM). The data were statistically analyzed by Graphpad prism (Version 7) using independent sample ‘t’ test. The mean (±SEM) of serum vitamin D of Group I and Group II were 16.37±0.78 kg/m2 &amp; 18.47±1.01 ng/ml respectively. Conclusion: Vitamin D deficiency is present in both groups. By this study we recommended that routine estimation of this parameter is important for early detection and prevention of complication related to Asthma-COPD overlap for managing a healthy life. Medicine Today 2024, Vol.36 (2): 120-123

TMEM176B Prevents and alleviates bleomycin-induced pulmonary fibrosis via inhibiting transforming growth factor β-Smad signaling

Pulmonary fibrosis is a severe and progressive lung disease characterized by the abnormal accumulation of extracellular matrix, leading to scarring and loss of normal lung function. Recent bioinformatics analysis through the Gene Expression Omnibus (GEO) database identified a significant downregulation of Transmembrane Protein 176B (TMEM176B), previously unexplored in the context of fibrotic lung tissues. To investigate the functional role of TMEM176B, we induced pulmonary fibrosis in mice using bleomycin, TGFβ1, and silica, which consistently resulted in a marked decrease in TMEM176B expression. Intriguingly, overexpression of TMEM176B via adenoviral vectors prior to the induction of fibrosis led to significant improvements in fibrotic manifestations and lung function. Mechanistically, TMEM176B appears to mitigate pulmonary fibrosis by inhibiting the TGFβ1-SMAD signaling pathway, which is a critical mediator of fibroblast proliferation and differentiation and promotes extracellular matrix production. These findings suggest that TMEM176B plays an inhibitory role in the pathophysiological processes of pulmonary fibrosis, highlighting its potential as a therapeutic target.

Dendritic Cell - Fibroblast Crosstalk via TLR9 and AHR Signaling Drives Lung Fibrogenesis.

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive scarring and loss of lung function. With limited treatment options, patients succumb to the disease within 2-5 years. The molecular pathogenesis of IPF regarding the immunologic changes that occur is poorly understood. We characterize a role for non-canonical aryl-hydrocarbon receptor signaling (ncAHR) in dendritic cells (DCs) that leads to production of IL-6 and IL-17, promoting fibrosis. TLR9 signaling in myofibroblasts is shown to regulate production of TDO2 which converts tryptophan into the endogenous AHR ligand kynurenine. Mice with augmented ncAHR signaling were created by crossing floxed AHR exon-2 deletion mice (AHR Δex2 ) with mice harboring a CD11c-Cre. Bleomycin was used to study fibrotic pathogenesis. Isolated CD11c+ cells and primary fibroblasts were treated ex-vivo with relevant TLR agonists and AHR modulating compounds to study how AHR signaling influenced inflammatory cytokine production. Human datasets were also interrogated. Inhibition of all AHR signaling rescued fibrosis, however, AHR Δex2 mice treated with bleomycin developed more fibrosis and DCs from these mice were hyperinflammatory and profibrotic upon adoptive transfer. Treatment of fibrotic fibroblasts with TLR9 agonist increased expression of TDO2. Study of human samples corroborate the relevance of these findings in IPF patients. We also, for the first time, identify that AHR exon-2 floxed mice retain capacity for ncAHR signaling.

Quantifying abnormal alveolar microstructure in cystic fibrosis lung disease via hyperpolarized 129Xe diffusion MRI

RationaleCystic Fibrosis (CF) progresses through recurrent infection and inflammation, causing permanent lung function loss and airway remodeling. CT scans reveal abnormally low-density lung parenchyma in CF, but its microstructural nature remains insufficiently explored due to clinical CT limitations. To this end, diffusion-weighted 129Xe MRI is a non-invasive and validated measure of lung microstructure. In this work, we investigate microstructural changes in people with CF (pwCF) relative to age-matched, healthy subjects using comprehensive imaging and analysis involving pulmonary-function tests (PFTs), and 129Xe MRI. Methods38 healthy subjects (age 6–40; 17.2 ± 9.5 years) and 39 pwCF (age 6–40; 15.6 ± 8.0 years) underwent 129Xe-diffusion MRI and PFTs. The distribution of diffusion measurements (i.e., apparent diffusion coefficients (ADC) and morphometric parameters) was assessed via linear binning (LB). The resulting volume percentages of bins were compared between controls and pwCF. Mean ADC and morphometric parameters were also correlated with PFTs. ResultsMean whole-lung ADC correlated significantly with age (P < 0.001) for both controls and CF, and with PFTs (P < 0.05) specifically for pwCF. Although there was no significant difference in mean ADC between controls and pwCF (P = 0.334), age-adjusted LB indicated significant voxel-level diffusion (i.e., ADC and morphometric parameters) differences in pwCF compared to controls (P < 0.05). Conclusions129Xe diffusion MRI revealed microstructural abnormalities in CF lung disease. Smaller microstructural size may reflect compression from overall higher lung density due to interstitial inflammation, fibrosis, or other pathological changes. While elevated microstructural size may indicate emphysema-like remodeling due to chronic inflammation and infection.

Evidence from recent clinical trials in fibrotic interstitial lung diseases.

Idiopathic pulmonary fibrosis (IPF) is the prototype of fibrosing interstitial lung diseases. It is mirrored by progressive pulmonary fibrosis (PPF), an umbrella term which characterizes disease behavior of various fibrotic interstitial lung diseases with irreversible progression, accounting for loss of lung function, exercise intolerance and respiratory failure leading to early mortality. Pirfenidone and nintedanib halve the decline in lung function but do not halt disease progression. Since the publication in 2014 of pivotal pirfenidone and nintedanib studies, a number of clinical trials were conducted, many of them did not reach their primary endpoints. In IPF, promising phase 2 trials were followed by large phase 3 trials that did not confirm a favorable efficacy to tolerability favorable profile, including those with ziritaxestat, an autotaxin-1 inhibitor, zinpentraxin-alpha (human recombinant pentraxin-2), and the monoclonal antibody pamrevlumab targeting connective tissue growth factor. Nevertheless, newer compounds that hold promise are currently being evaluated in phase 3 or phase 2b randomized controlled trials, including: nerandomilast, a preferential phosphodiesterase 4B inhibitor; admilparant, a lysophosphatidic acid receptor antagonist; inhaled treprostinil, a prostacyclin agonist; and bexotegrast, a dual-selective inhibitor of αvβ6 and αvβ1 integrins. Nerandomilast, admilparant, inhaled treprostinil, and inhaled AP01 (pirfenidone), are currently studied in patients with PPF. Despite recent frustrating negative results, there is a growing portfolio of candidate drugs developed in both IPF and PPF.

Efficacy and safety of LAU-7b in a Phase 2 trial in adults with cystic fibrosis

BackgroundLung inflammation is associated with tissue damage in cystic fibrosis (CF). LAU-7b, a novel oral drug candidate, was shown to control inflammation and stabilize CFTR protein in the epithelial membrane during inflammatory stress in preclinical models of CF. MethodsA double-blind, randomized, placebo-controlled Phase 2 study was conducted to evaluate efficacy and safety of LAU-7b in adults with CF. LAU-7b or placebo was administered over 24 weeks as six 21-day treatment cycles each separated by 7 days. The primary efficacy endpoint was the absolute change from baseline in percent predicted forced expiratory volume in 1 second (ppFEV1) at 24 weeks. ResultsA total of 166 subjects received at least one dose of study drug (Intent-To-Treat population, ITT), of which 122 received ≥5 treatment cycles (Per-Protocol population, PP). Both treatment arms showed a mean lung function loss at 24 weeks of 1.18 ppFEV1 points with LAU-7b and 1.95 ppFEV1 with placebo, a 0.77 ppFEV1 (40 s) difference, p=0.345, and a 0.95 ppFEV1 (49 %) difference in the same direction in PP population, p=0.263. Primary analysis of mean ppFEV1 through 24 weeks showed differences of 1.01 and 1.23 ppFEV1, in the ITT (65 % less loss, p=0.067) and PP populations (78 % less loss, reaching statistical significance p=0.049), respectively. LAU-7b had an acceptable safety profile. ConclusionAlthough the study did not meet its primary efficacy endpoint in the ITT population, LAU-7b was generally well tolerated and showed evidence of preservation of lung function to support further development.

Serum metabolomics analysis of patients with chronic obstructive pulmonary disease and 'frequent exacerbator' phenotype.

Chronic obstructive pulmonary disease (COPD) exacerbations accelerate loss of lung function and increased mortality. The complex nature of COPD presents challenges in accurately predicting and understanding frequent exacerbations. The present study aimed to assess the metabolic characteristics of the frequent exacerbation of COPD (COPD‑FE) phenotype, identify potential metabolic biomarkers associated with COPD‑FE risk and evaluate the underlying pathogenic mechanisms. An internal cohort of 30 stable patients with COPD was recruited. A widely targeted metabolomics approach was used to detect and compare serum metabolite expression profiles between patients with COPD‑FE and patients with non‑frequent exacerbation of COPD (COPD‑NE). Bioinformatics analysis was used for pathway enrichment analysis of the identified metabolites. Spearman's correlation analysis assessed the associations between metabolites and clinical indicators, while receiver operating characteristic (ROC) analysis evaluated the ability of metabolites to distinguish between two groups. An external cohort of 20 patients with COPD validated findings from the internal cohort. Out of the 484 detected metabolites, 25 exhibited significant differences between COPD‑FE and COPD‑NE. Metabolomic analysis revealed differences in lipid, energy, amino acid and immunity pathways. Spearman's correlation analysis demonstrated associations between metabolites and clinical indicators of acute exacerbation risk. ROC analysis demonstrated that the area under the curve (AUC) values for D‑fructose 1,6‑bisphosphate (AUC=0.871), arginine (AUC=0.836), L‑2‑hydroxyglutarate (L‑2HG; AUC=0.849), diacylglycerol (DG) (16:0/20:5) (AUC=0.827), DG (16:0/20:4) (AUC=0.818) and carnitine‑C18:2 (AUC=0.804) were >0.8, highlighting their discriminative capacity between the two groups. External validation results demonstrated that DG (16:0/20:5), DG (16:0/20:4), carnitine‑C18:2 and L‑2HG were significantly different between patients with COPD‑FE and those with COPD‑NE. In conclusion, the present study offers insights into early identification, mechanistic understanding and personalized management of the COPD‑FE phenotype.

The disruptive effects of COPD exacerbation-associated factors on epithelial repair responses.

Exacerbations of chronic obstructive pulmonary disease (COPD) increase mortality risk and can lead to accelerated loss of lung function. The increased inflammatory response during exacerbations contributes to worsening of airflow limitation, but whether it also impacts epithelial repair is unclear. Therefore, we studied the effect of the soluble factor micro-environment during COPD exacerbations on epithelial repair using an exacerbation cocktail (EC), composed of four factors that are increased in COPD lungs during exacerbations (IL-1β, IL-6, IL-8, TNF-α). Mouse organoids (primary CD31-CD45-Epcam+ cells co-cultured with CCL206 fibroblasts) were used to study epithelial progenitor behavior. Mature epithelial cell responses were evaluated using mouse precision cut lung slices (PCLS). The expression of epithelial supportive factors was assessed in CCL206 fibroblasts and primary human lung fibroblasts. EC exposure increased the number and size of organoids formed, and upregulated Lamp3, Muc5ac and Muc5b expression in day 14 organoids. In PCLS, EC imparted no effect on epithelial marker expression. Pre-treatment of CCL206 fibroblasts with EC was sufficient to increase organoid formation. Additionally, the expression of Il33, Tgfa and Areg was increased in CCL206 fibroblasts from EC treated organoids, but these factors individually did not affect organoid formation or size. However, TGF-α downregulated Foxj1 expression and upregulated Aqp5 expression in day 14 organoids. EC exposure stimulates organoid formation and growth, but it alters epithelial differentiation. EC changes the epithelial progenitor support function of fibroblasts which contributes to observed effects on epithelial progenitors.

Extracorporeal photopheresis (ECP) in the treatment of chronic lung allograft dysfunction (CLAD): a prospective, multicentre, open-label, randomised controlled trial studying the addition of ECP to standard care in the treatment of bilateral lung transplant patients with CLAD (E-CLAD UK)

BackgroundLong-term survival after lung transplantation is limited compared with other organ transplants. The main cause is development of progressive immune-mediated damage to the lung allograft. This damage, which can develop...

Long-Term Follow-Up after Laser-Assisted Pulmonary Metastasectomy Shows Complete Lung Function Recovery.

Preserving maximum lung function is a fundamental goal of parenchymal-sparing pulmonary laser surgery. Long-term studies for follow-up of lung function after pulmonary laser metastasectomy are lacking. However, a sufficient postoperative lung function is essential for quality of life and reduces potential postoperative complications. In this study, we investigate the extent of loss in lung function following pulmonary laser resection after three, six, and twelve months. We conducted a retrospective analysis using a prospective database of 4595 patients, focusing on 126 patients who underwent unilateral pulmonary laser resection for lung metastases from 1996 to 2022 using a 1318 nm Nd:YAG laser or a high-power pure diode laser. Results show that from these patients, a median of three pulmonary nodules were removed, with 75% presenting central lung lesions and 25% peripheral lesions. The median preoperative FEV1 was 98% of the predicted value, decreasing to 71% postoperatively but improving to 90% after three months, 93% after six months, and 96% after twelve months. Statistical analysis using the Friedman test indicated no significant difference in FEV1 between preoperative levels and those at six and twelve months post-surgery. The findings confirm that pulmonary laser surgery effectively preserves lung function over time, with patients generally regaining their preoperative lung function within a year, regardless of the metastases' location.

Five-Year Outcomes among U.S. Bronchiectasis and NTM Research Registry Patients.

Rationale: Nontuberculous mycobacteria (NTM) are prevalent among patients with bronchiectasis. However, the long-term natural history of patients with NTM and bronchiectasis is not well described. Objectives: To assess the impact of NTM on 5-year clinical outcomes and mortality in patients with bronchiectasis. Methods: Patients in the Bronchiectasis and NTM Research Registry with ⩾5 years of follow-up were eligible. Data were collected for all-cause mortality, lung function, exacerbations, hospitalizations, and disease severity. Outcomes were compared between patients with and without NTM at baseline. Mortality was assessed using Cox proportional hazards models and the log-rank test. Measurements and Main Results: In total, 2,634 patients were included: 1,549 (58.8%) with and 1,085 (41.2%) without NTM at baseline. All-cause mortality (95% confidence interval) at Year 5 was 12.1% (10.5%, 13.7%) overall, 12.6% (10.5%, 14.8%) in patients with NTM, and 11.5% (9.0%, 13.9%) in patients without NTM. Independent predictors of 5-year mortality were baseline FEV1 percent predicted, age, hospitalization within 2 years before baseline, body mass index, and sex (all P < 0.01). The probabilities of acquiring NTM or Pseudomonas aeruginosa were approximately 4% and 3% per year, respectively. Spirometry, exacerbations, and hospitalizations were similar, regardless of NTM status, except that annual exacerbations were lower in patients with NTM (P < 0.05). Conclusions: Outcomes, including exacerbations, hospitalizations, rate of loss of lung function, and mortality rate, were similar across 5 years in patients with bronchiectasis with or without NTM.

E038 Predictors for pulmonary function decline in interstitial lung disease

Abstract Background/Aims Interstitial lung disease (ILD) is commonly associated with a decline in forced vital capacity (FVC). The most substantial loss of lung function typically occurs early in the course of the disease. The natural history of ILD varies among individuals. Several studies have employed FVC decline as the primary endpoint and NICE has recently approved antifibrotics based on this as an endpoint. An FVC reduction exceeding 10% has consistently been shown to correlate with poorer survival, leading to evidence-based guidelines recommending, an absolute decrease in FVC of 10% can be used as a surrogate marker of mortality. Aim: To obtain insights into the decline in lung function in patients with ILD, by comparing FVC measurements at baseline and 52 weeks. We hypothesised that the rate of absolute decline is increased with higher age, active smoking, sex, duration of ILD and comorbidities. Methods This was a retrospective study conducted at Southend University Hospital, involving a single-centre cohort of ILD patients identified from the ILD multidisciplinary team from 2016-June 2023. Data collection included parameters such as age at ILD onset, gender, occupation, smoking history, serial pulmonary function tests, imaging, comorbidities, survival outcomes, causes of death, and treatment regimens. Results Data from 197 patients were included in this study. Mean age of the cohort at diagnosis was 74. Men 112 (57%) and females 85 (43%). Among the study population 128 had a history of ex or current smoking. Mean duration of ILD was 40 months, ranging from 2 to 168 months. Of the participants 115 were deceased &amp; 83 remained alive. We included most common conditions in the analysis: idiopathic pulmonary fibrosis (IPF) = 65, RA = 22, idiopathic pulmonary fibrosis with autoimmune features (IPAF) =15, hypersensitivity pneumonitis (HP) = 20, unclassified=25, SSc-ILD = 13, Sjogren’s = 2, myositis = 1, vasculitis = 3 and sarcoidosis = 7. For analysis, we included RA, SSc, Sjogren’s, vasculitis, ankylosing spondylitis, myositis, and sarcoidosis in the CTD -ILD group. 23 were excluded from analysis (COOP, OP, CPFE, PPFE and drug induced pneumonitis). We categorised disease progression as severe, if FVC decline exceeded 10%. This was achieved as follows; 3/36 in CTD -ILD, 2/10 in IPAF, 6/16 in HP, 5/19 unclassified in ILD and 14/47 in IPF (χ²=7.5, p = 0.109). Moderate disease progression was defined as an FVC decline between 5- 10%. It was achieved in 6/36 in CTD -ILD, 3/16 in HP, 1/19 in unclassified and 5/47 in IPF (χ²=3.8, p = 0.439).In univariate analysis, none of the predictors achieved significance for severe or moderate progression among subgroups. In multivariate analysis, only the disease subgroup achieved significance in predicting significant lung function decline progression. Conclusion The rate of decline in lung function during follow-up differed across the subgroups based on clinical factors and demographics. This data supports the unpredictable nature of ILD. Disclosure G.M. Koduri: Corporate appointments; NONE. Consultancies; NONE. Shareholder/stock ownership; NONE. Royalties; NONE. Honoraria; NONE. Member of speakers’ bureau; NONE. Grants/research support; NONE. Other; NONE.

Lymphangioleiomyomatosis in patients with tuberous sclerosis: a national centre audit

BackgroundLymphangioleiomyomatosis (LAM) is common in tuberous sclerosis complex (TSC) yet under recognised with management mostly based upon evidence obtained from patients with sporadic LAM. We performed a prospective audit of patients with TSC-LAM attending a national referral centre to inform management guidelines.MethodsThe UK LAM Centre was established in 2011 and conducts a prospective audit of pre-defined quality outcomes for all subjects. Audit data are reported on all patients with TSC-LAM and a comparator population of patients with sporadic LAM.ResultsBetween 2011 and 2022, 73 patients were seen with TSC-LAM. All were women with a mean (SD) age of 39 (12) years. Referral rates were similar over the study period including after the introduction of CT screening. Median age of diagnosis with TSC was 11 years (range 0–70) with one third diagnosed with TSC as adults. Compared with all TSC patients in the ‘TOSCA’ registry, TSC-LAM patients tended to have been diagnosed with TSC at an older age, had fewer neuro-cognitive manifestations and were more likely to have angiomyolipoma. The most common presentations of TSC-LAM were following workup for angiomyolipoma, pneumothorax or dyspnoea with only one fifth detected after CT screening. Baseline FEV1 and DLCO at first assessment were reduced to 77 and 63% predicted respectively and were similar to patients with sporadic LAM. During follow-up, FEV1 fell by a mean of 81 ml/year and DLCO fell by 0.309 mmol/ml/kPa/year in patients not being treated with an mTOR inhibitor. 55% required treatment with either sirolimus or Everolimus for LAM or angiomyolipoma respectively. For those treated with an mTOR inhibitor, mean FEV1 fell by 3 ml/year and DLCO increased by 0.032 mmol/ml/kPa/year and was similar to sporadic LAM. Risk of death due to LAM or need for lung transplant in patients with TSC-LAM was 0.67%/year.ConclusionsDespite screening recommendations, LAM is often diagnosed in TSC after symptoms develop which may delay treatment. Complications including pneumothorax and loss of lung function are significant and similar to sporadic LAM. Work is needed to implement the recommended CT screening for LAM and improve respiratory care for TSC-LAM.

Understanding the Gaps in the Reporting of COPD Exacerbations by Patients: A Review.

Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with loss of lung function, poor quality of life, loss of exercise capacity, risk of serious cardiovascular events, hospitalization, and death. However, patients underreport exacerbations, and evidence suggests that unreported exacerbations have similar negative health implications for patients as those that are reported. Whilst there is guidance for physicians to identify patients who are at risk of exacerbations, they do not help patients recognise and report them. Newly developed tools, such as the COPD Exacerbation Recognition Tool (CERT) have been designed to achieve this objective. This review focuses on the underreporting of COPD exacerbations by patients, the factors associated with this, the consequences of underreporting, and potential solutions.

A Comparison of the Effectiveness of Nintedanib and Pirfenidone in Treating Idiopathic Pulmonary Fibrosis: A Systematic Review.

Idiopathic pulmonary fibrosis (IPF), which shares a radiographic pattern with the usual interstitial pneumonia (UIP), is a specific form of chronic and progressive interstitial lung disorder resulting in persistent fibrosis and impaired lung function. Most of the patients suffer from dyspnea which adversely affects health-related quality of life (HRQOL). The underlying etiology of the disease is not yet understood, but research done on the subject reveals that aberrant repair mechanisms and dysregulated immune responses may be the cause.It can affect any age group but predominantly affects patients who are above 50 years of age. It has been observed that in addition to age, the reasons are also related to smoking, pollution, and inhalation of harmful elements. As the cause of IPF is still unknown and there is no cure yet, presently, it is treated to delay lung function loss with antifibrotic medications, nintedanib, and pirfenidone. However, both nintedanib and perfenidone have side effects which affect different patients in different ways and with different levels of severity, thereby making the treatment even more challenging for medical practitioners. The present systematic review aims at studying the efficacy of pirfenidone and nintedanib in relieving symptoms and in extending survival in patients. A detailed search was done in relevant articles listed in PubMed, ScienceDirect, and the New England Journal of Medicine between 2018 and 2023. It was observed that the most accepted way of measuring the progression of IPF is the evaluation of pulmonary function by assessing the forced vital capacity (FVC). Several studies have shown that the decline in FVC over a period of 6-12 months is directly associated with a higher mortality rate. The outcomes were similar in both male and female irrespective of age, gender, and ethnicity. However, some patients being treated with pirfenidone and nintedanib experienced various side-effects which were mainly gastrointestinal like diarrhea, dyspepsia, and vomiting. In the case of pirfenidone, some patients also experienced photosensitivity and skin rashes. In cases where the side-effects are extremely severe and are more threatening than the disease itself, the treatment has to be discontinued. The survival rate in patients with IPF is marked by a median of 3-5 yearsthat is even lower than many cancers; hence, the treatment should be started as soon as the disease is detected. However, further research is needed to establish the etiology of IPF and to establish treatments that can stop its progression.

CF Lung Disease - a German S3 Guideline: Pseudomonas aeruginosa

Cystic Fibrosis (CF) is the most common autosomal recessive genetic multisystemic disease. In Germany, it affects at least 8000 people. The disease is caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene leading to dysfunction of CFTR, a transmembrane chloride channel. This defect causes insufficient hydration of the airway epithelial lining fluid which leads to reduction of the mucociliary clearance.Even if highly effective, CFTR modulator therapy has been available for some years and people with CF are getting much older than before, recurrent and chronic infections of the airways as well as pulmonary exacerbations still occur. In adult CF life, Pseudomonas aeruginosa (PA) is the most relevant pathogen in colonisation and chronic infection of the lung, leading to further loss of lung function. There are many possibilities to treat PA-infection.This is a S3-clinical guideline which implements a definition for chronic PA-infection and demonstrates evidence-based diagnostic methods and medical treatment in order to give guidance for individual treatment options.

Accelerated Lung Function Decline and Mucus-Microbe Evolution in Chronic Obstructive Pulmonary Disease.

Rationale: Progressive lung function loss is recognized in chronic obstructive pulmonary disease (COPD); however, no study concurrently evaluates how accelerated lung function decline relates to mucus properties and the microbiome in COPD. Objectives: Longitudinal assessment of mucus and microbiome changes accompanying accelerated lung function decline in patients COPD. Methods: This was a prospective, longitudinal assessment of the London COPD cohort exhibiting the greatest FEV1 decline (n = 30; accelerated decline; 156 ml/yr FEV1 loss) and with no FEV1 decline (n = 28; nondecline; 49 ml/yr FEV1 gain) over time. Lung microbiomes from paired sputum (total 116 specimens) were assessed by shotgun metagenomics and corresponding mucus profiles evaluated for biochemical and biophysical properties. Measurements and Main Results: Biochemical and biophysical mucus properties are significantly altered in the accelerated decline group. Unsupervised principal component analysis showed clear separation, with mucus biochemistry associated with accelerated decline, whereas biophysical mucus characteristics contributed to interindividual variability. When mucus and microbes are considered together, an accelerated decline mucus-microbiome association emerges, characterized by increased mucin (MUC5AC [mucin 5AC] and MUC5B [mucin 5B]) concentration and the presence of Achromobacter and Klebsiella. As COPD progresses, mucus-microbiome shifts occur, initially characterized by low mucin concentration and transition from viscous to elastic dominance accompanied by the commensals Veillonella, Gemella, Rothia, and Prevotella (Global Initiative for Chronic Obstructive Lung Disease [GOLD] A and B) before transition to increased mucus viscosity, mucins, and DNA concentration together with the emergence of pathogenic microorganisms including Haemophilus, Moraxella, and Pseudomonas (GOLD E). Conclusions: Mucus-microbiome associations evolve over time with accelerated lung function decline, symptom progression, and exacerbations affording fresh therapeutic opportunities for early intervention.