Pathogenesis and management of emphysema in people with HIV.

INTRODUCTION: Since early in the HIV epidemic, emphysema has been identified among people with HIV (PWH) and has been associated with increased mortality. Smoking cessation is key to risk reduction. Health maintenance for PWH and emphysema should ensure appropriate vaccination and lung cancer screening. Treatment should adhere to inhaler guidelines for the general population, but inhaled corticosteroid (ICS) should be used with caution. Frontiers in treatment include targeted therapeutics. Major knowledge gaps exist in the epidemiology of and optimal care for PWH and emphysema, particularly in low and middle-income countries (LMIC). AREAS COVERED: Topics addressed include risk factors, pathogenesis, current treatment and prevention strategies, and frontiers in research. EXPERT OPINION: There are limited data on the epidemiology of emphysema in LMIC, where more than 90% of deaths from COPD occur and where the morbidity of HIV is most heavily concentrated. The population of PWH is aging, and age-related co-morbidities such as emphysema will only increase in salience. Over the next 5 years, the authors anticipate novel trials of targeted therapy for emphysema specific to PWH, and we anticipate a growing body of evidence to inform optimal clinical care for lung health among PWH in LMIC.

Mesenchymal Stem Cells from COPD Patients Are Capable of Restoring Elastase-Induced Emphysema in a Murine Experimental Model.

COPD is a chronic lung disease that affects millions of people, declining their lung function and impairing their life quality. Despite years of research and drug approvals, we are still not capable of halting progression or restoring normal lung function. Mesenchymal stem cells (MSC) are cells with extraordinary repair capacity, and MSC-based therapy brings future hope for COPD treatment, although the best source and route of administration are unclear. MSC from adipose tissue (AD-MSC) represents an option for autologous treatment; however, they could be less effective than donor MSC. We compared in vitro behavior of AD-MSC from COPD and non-COPD individuals by migration/proliferation assay, and tested their therapeutic potential in an elastase mouse model. In addition, we tested intravenous versus intratracheal routes, inoculating umbilical cord (UC) MSC and analyzed molecular changes by protein array. Although COPD AD-MSC have impaired migratory response to VEGF and cigarette smoke, they were as efficient as non-COPD in reducing elastase-induced lung emphysema. UC-MSC reduced lung emphysema regardless of the administration route and modified the inflammatory profile in elastase-treated mice. Our data demonstrate equal therapeutic potential of AD-MSC from COPD and non-COPD subjects in the pre-clinical model, thus supporting their autologous use in disease.

Intratracheally injected human-induced pluripotent stem cell-derived pneumocytes and endothelial cells engraft in the distal lung and ameliorate emphysema in a rat model.

OBJECTIVES: Pulmonary emphysema is characterized by the destruction of alveolar units and reduced gas exchange capacity. In the present study, we aimed to deliver induced pluripotent stem cell-derived endothelial cells and pneumocytes to repair and regenerate distal lung tissue in an elastase-induced emphysema model. METHODS: We induced emphysema in athymic rats via intratracheal injection of elastase as previously reported. At 21 and 35 days after elastase treatment, we suspended 80 million induced pluripotent stem cell-derived endothelial cells and 20 million induced pluripotent stem cell-derived pneumocytes in hydrogel and injected the mixture intratracheally. On day 49 after elastase treatment, we performed imaging, functional analysis, and collected lungs for histology. RESULTS: Using immunofluorescence detection of human-specific human leukocyte antigen 1, human-specific CD31, and anti--green fluorescent protein for the reporter labeled pneumocytes, we found that transplanted cells engrafted in 14.69% ± 0.95% of the host alveoli and fully integrated to form vascularized alveoli together with host cells. Transmission electron microscopy confirmed the incorporation of the transplanted human cells and the formation of a blood-air barrier. Human endothelial cells formed perfused vasculature. Computed tomography scans revealed improved vascular density and decelerated emphysema progression in cell-treated lungs. Proliferation of both human and rat cell was higher in cell-treated versus nontreated controls. Cell treatment reduced alveolar enlargement, improved dynamic compliance and residual volume, and improved diffusion capacity. CONCLUSIONS: Our findings suggest that human induced pluripotent stem cell-derived distal lung cells can engraft in emphysematous lungs and participate in the formation of functional distal lung units to ameliorate the progression of emphysema.

Bronchoscopic Measurement of Collateral Ventilation: State of the Art.

Endoscopic lung volume reduction procedure with valves is a well-studied treatment option for advanced lung emphysema to target lung hyperinflation in carefully selected patients with COPD. Before valve implantation, collateral ventilation (CV) of the target lobe needs to be assessed to obtain an optimal treatment effect. The analysis of CV according to current standards occurs via an in vivo assessment with the Chartis®system (PulmonX Inc., Redwood City, CA, USA) and a computed tomography (CT) scan of the thorax with interlobar fissure analysis. The focus of this review is to provide detailed information about the Chartis®procedure and interpretation of Chartis® phenotypes. As a main tool in the assessment of CV and being a safe procedure, the Chartis® assessment should be performed by default to confirm interlobar fissure analysis in most emphysema patients. Based on the obtained results, lung volume reduction therapy options should be discussed in an interdisciplinary emphysema conference.

Pneumothorax in patients with COPD and emphysema receiving home chronic non-invasive ventilation: is it the emphysema phenotype or ventilator setting?

We describe three patients with chronic obstructive pulmonary disease (COPD) and emphysema who developed a pneumothorax while receiving chronic home non-invasive ventilation (NIV). These cases raise the question whether the high alveolar pressures given by NIV may have contributed to the development of their pneumothorax by barotrauma. Pneumothorax in patients with COPD receiving NIV is uncommon, the pressures in our patients with COPD who developed pneumothorax were not extremely high and time to development of pneumothorax was relatively long after the initiation of NIV. Further, in our patients, the CT scan showed paraseptal emphysema, a known risk factor for pneumothorax. This suggests that COPD/emphysema phenotype is probably a more important factor for indicating pneumothorax risk than ventilator settings. Better phenotyping of patients with COPD in whom benefits of NIV can be expected at minimal risk of serious side-effects is needed to inform our patients properly and bring the field of chronic NIV in COPD forward.

Reporte de caso: hemoptisis masiva como manifestación clínica de un síndrome de Swyer-James-Mac Leod / Case report: massive hemoptysis as a clinical manifestation of Swyer-James-Mac Leod syndrome

El síndrome de Swyer-James-Mac Leod es una entidad poco frecuente adquirida en la infancia, generalmente tras una infección pulmonar moderada a grave de tipo bronquiolitis o neumonía, generalmente virales. Ocasionalmente se tiene el antecedente de infecciones repetidas de este tipo. Consiste en el desarrollo de enfisema hipoplásico pulmonar unilateral, que puede a veces relacionarse con bronquiectasias ipsilaterales o bilaterales, obstrucción fija al flujo aéreo y puede también asociarse a reducción del flujo sanguíneo del pulmón hipoplásico, de manera focal o difusa, con o sin tortuosidad de la vascularización proximal y a veces con una compensación del pulmón contralateral, en forma de sobredistensión e hiperflujo vascular relativo. Presentamos el caso de un varón de 79 años de edad con antecedentes de infecciones tipo bronquiolitis virales repetidas en la infancia, obstrucción fija grave al flujo aéreo y hemoptisis masiva secundaria a una infección por Pseudomonas aeruginosa sensible a la terapia antibiótica habitual.

Swyer-James-Mac Leod syndrome is a rare condition acquired in childhood, usually after a moderate to severe lung infection such as bronchiolitis or pneumonia, usually viral. Occasionally there is a history of repeated infections of this type. It consists of the development of unilateral pulmonary hypoplastic emphysema, which can sometimes be related to ipsilateral or bilateral bronchiectasis, fixed airflow obstruction, and may also be associated with reduced blood flow in the hypoplastic lung, with or without tortuosity of the proximal vascular supply and sometimes with compensation from the contralateral lung, in the form of overdistension and relative vascular hyperflow. We present the case of a 79-year-old man with a history of recurrent viral bronchiolitis-type infections in childhood, severe fixed airflow obstruction, and massive hemoptysis secondary to a Pseudomonas aeruginosa infection sensitive to usual antibiotic therapy.

Reduction of Emphysema Severity by Human Umbilical Cord-Derived Mesenchymal Stem Cells in Mice.

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality in chronic lung disease patients throughout the world. Mesenchymal stem cells (MSCs) have been shown to regulate immunomodulatory, anti-inflammatory, and regenerative responses. However, the effects of human-umbilical-cord-derived mesenchymal stem cells (hUC-MSCs) on the lung pathophysiology of COPD remain unclear. We aimed to investigate the role of hUC-MSCs in emphysema severity and Yes-associated protein (Yap) phosphorylation (p-Yap) in a porcine-pancreatic-elastase (PPE)-induced emphysema model. We observed that the emphysema percentages (normalized to the total lung volume) measured by chest computed tomography (CT) and exercise oxygen desaturation were significantly reduced by hUC-MSCs at 107 cells/kg body weight (BW) via intravenous administration in emphysematous mice (p < 0.05). Consistently, the emphysema index, as assessed by the mean linear intercept (MLI), significantly decreased with hUC-MSC administration at 3 × 106 and 107 cells/kg BW (p < 0.05). Changes in the lymphocytes, monocytes, and splenic cluster of differentiation 4-positive (CD4+) lymphocytes by PPE were significantly reversed by hUC-MSC administration in emphysematous mice (p < 0.05). An increasing neutrophil/lymphocyte ratio was reduced by hUC-MSCs at 3 × 106 and 107 cells/kg BW (p < 0.05). The higher levels of tumor necrosis factor (TNF)-α, keratinocyte chemoattractant (KC), and lactate dehydrogenase (LDH) in bronchoalveolar lavage fluid (BALF) were significantly decreased by hUC-MSC administration (p < 0.05). A decreasing p-Yap/Yap ratio in type II alveolar epithelial cells (AECII) of mice with PPE-induced emphysema was significantly increased by hUC-MSCs (p < 0.05). In conclusion, the administration of hUC-MSCs improved multiple pathophysiological features of mice with PPE-induced emphysema. The effectiveness of the treatment of pulmonary emphysema with hUC-MSCs provides an essential and significant foundation for future clinical studies of MSCs in COPD patients.

Spanish COPD Guidelines (GesEPOC 2021): Non-pharmacological Treatment Update. / Actualización 2021 de la Guía Española de la EPOC (GesEPOC). Tratamiento no farmacológico.

In addition to recommendations for pharmacological treatment stratified for risk and phenotype, the new 2021 edition of the Spanish COPD Guidelines (GesEPOC 2021) proposes a personalized approach to treatable traits, defined as a characteristic (clinical, physiological, or biological) that can be identified by diagnostic tests or biomarkers, for which a specific treatment is available. Some treatable traits, such as malnutrition, sedentarism, emphysema or respiratory failure, can be treated with non-pharmacological therapies, and this was not covered in detail in the guidelines. This section of GesEPOC 2021 includes a narrative update with recommendations on dietary treatment, physical activity, respiratory rehabilitation, oxygen therapy, non-invasive ventilation, volume reduction, and lung transplantation. A PICO question with recommendations on the use of supplemental oxygen during exercise in COPD patients without severe hypoxemia is also included.

MTMR14 Alleviates Chronic Obstructive Pulmonary Disease as a Regulator in Inflammation and Emphysema.

Extensive inflammation and apoptosis in structural cells of the lung are responsible for the progression and pathogenesis of chronic obstructive pulmonary disease (COPD). Myotubularin-related protein 14 (MTMR14) has been shown to participate in various biological processes, including apoptosis, inflammation, and autophagy. Nonetheless, the role of MTMR14 in COPD remains elusive. In the present study, we explored the expression of MTMR14 in human lung tissues and investigated the effects of overexpressed MTMR14 on in vitro and in vivo COPD models. Moreover, one of the possible mechanisms of MTMR14 alleviating COPD was explored based on mitochondrial function and mitophagy homeostasis. The results showed that MTMR14 expression was reduced in COPD patients' lungs in comparison to control subjects. MTMR14 overexpression inhibited cigarette smoke extract-induced inflammation and apoptosis and improved mitochondrial function and mitophagy in vitro. Further verification was carried out in COPD model mice. MTMR14 overexpression inhibited lung inflammation and reduced levels of IL-6 and KC in bronchoalveolar lavage fluid, as well as prevented emphysema and a decline in lung function. Furthermore, MTMR14 overexpression improved mitochondrial function and mitophagy to a certain extent. Collectively, our data support the hypothesis that MTMR14 participates in the pathogenesis of COPD. Improving mitochondrial function and mitophagy homeostasis may be one of the mechanisms by which MTMR14 alleviates COPD and may potentially be a novel therapeutic target for COPD.

Impact of Ventilation Modes on Bronchoscopic Chartis Assessment Outcome in Candidates for Endobronchial Valve Treatment.

BACKGROUND: Endobronchial valve therapy has proven to reduce lung hyperinflation and decrease disease burden in patients with severe lung emphysema. Exclusion of collateral ventilation (CV) of the targeted lobe by using an endobronchial assessment system (Chartis; PulmonX, Drive Redwood City, CA, USA) in combination with software-based fissure integrity analysis (FCS [fissure completeness score]) of computed tomography scans of the lung are established tools to select appropriate patients for endobronchial valve treatment. So far, there is no conclusive evidence if the ventilation mode during bronchoscopy impacts the outcome of Chartis assessments. METHODS: Patients with Chartis assessments and software-based quantification of FCS (StratX; PulmonX, Drive Redwood City, CA, USA) were enrolled in this retrospective study. During bronchoscopy, pulmonary fissure integrity was evaluated with the Chartis assessment system in each patient first under spontaneous breathing and subsequently under high-frequency (HF) jet ventilation. RESULTS: In total, 102 patients were analyzed. Four Chartis phenotypes CV positive (CV+), CV negative (CV-), low flow, and low plateau in spontaneous breathing and HF jet ventilation were identified. The frequency of each Chartis phenotype per lobe was similar in both settings. When comparing Chartis assessments in spontaneous breathing and HF jet ventilation, there was an overall good concordance rate for all analyzed fissures. In agreement, receiver operating characteristic analysis of the FCS showed an almost similar prediction for CV+ and CV- status independent of the ventilation modes. CONCLUSION: Chartis assessment in spontaneous breathing and HF jet ventilation had similar rates in detecting CV in lung emphysema. Our results suggest that both modes are equivalent for the assessment of CV.

[Management of unilateral acquired pulmonary bullous emphysema in a premature infant through selective bronchial intubation. Case report and review of literature]. / Manejo de enfisema intersticial unilateral adquirido en un recién nacido prematuro mediante intubación bronquial selectiva: Descripción de un caso y revisión de la literatura.

INTRODUCTION: Acquired pulmonary bullous emphysema is an infrequent complication of assisted ventilation in the premature infant that is difficult to manage. OBJECTIVE: The goal of this report is to present the case of a premature infant who required selective bronchial intubation as well as to provide a review of the current literature on the subject. CLINICAL CASE: The patient is a 27-week gestational age neonatal female patient whose clinical course was complicated by left unilateral bullous emphysema during assisted ventilation for respiratory distress syndrome. Lower peak inspiratory pressures, higher res piratory frequencies, patient positioning, and lower inspiration time failed to improve the patient's condition. The left lung became critically overinflated and compressed the right lung to the point of atelectasis. The patient was selectively mono intubated through the right main bronchus, which resulted in a collapse of the left emphysematous lung. Single right lung ventilation was continued for 48 hours before restarting conventional ventilation of both lungs. Our patient improved significantly, was extubated 6 days after the procedure and later discharged home with normal chest x-ray images. CONCLUSION: Selective bronchial intubation is a safe and effective procedure in cases of acquired bu llous emphysema when usual ventilatory management fails.

Human Adipose-Derived Mesenchymal Stem Cells Ameliorate Elastase-Induced Emphysema in Mice by Mesenchymal-Epithelial Transition.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is a worldwide problem because of its high prevalence and mortality. However, there is no fundamental treatment to ameliorate their pathological change in COPD lung. Recently, adipose-derived mesenchymal stem cells (ADSCs) have attracted attention in the field of regenerative medicine to repair damaged organs. Moreover, their utility in treating respiratory diseases has been reported in some animal models. However, the detailed mechanism by which ADSCs improve chronic respiratory diseases, including COPD, remains to be elucidated. We examined whether human ADSCs (hADSCs) ameliorated elastase-induced emphysema and whether hADSCs differentiated into alveolar epithelial cells in a murine model of COPD. METHODS: Female SCID-beige mice (6 weeks old) were divided into the following four groups according to whether they received an intratracheal injection of phosphate-buffered saline or porcine pancreatic elastase, and whether they received an intravenous injection of saline or hADSCs 3 days after intratracheal injection; Control group, hADSC group, Elastase group, and Elastase-hADSC group. We evaluated the lung function, assessed histological changes, and compared gene expression between hADSCs isolated from the lung of Elastase-hADSC group and naïve hADSCs 28 days after saline or elastase administration. RESULTS: hADSCs improved the pathogenesis of COPD, including the mean linear intercept and forced expiratory volume, in an elastase-induced emphysema model in mice. Furthermore, hADSCs were observed in the lungs of elastase-treated mice at 25 days after administration. These cells expressed genes related to mesenchymal-epithelial transition and surface markers of alveolar epithelial cells, such as TTF-1, ß-catenin, and E-cadherin. CONCLUSION: hADSCs have the potential to improve the pathogenesis of COPD by differentiating into alveolar epithelial cells by mesenchymal-epithelial transition.

Effect of Endobronchial Coils on Exercise Tolerance and Lung Functions in Patients with Severe Emphysema - A Retrospective Cohort Study of 48 Patients.

BACKGROUND: Lung volume reduction with endobronchial coils treatment (ECT), for patients with severe emphysema, has shown modest improvement in exercise capacity and lung functions in clinical trials, yet the benefit of this procedure is still unclear. METHODS: We conducted a multicenter retrospective cohort study including all patients who underwent ECT in Israel and a propensity score matched control group of patients with chronic obstructive pulmonary disease (COPD) that were treated with usual care. The primary outcome was six-minute walk test distance (6MWTD), secondary outcomes were lung function tests and patient survival. RESULTS: Overall, 46 patients were included in the ECT group. Their mean 6MWTD at baseline and at 6 and at 24 months post procedure was 331.0±101.4, 372.9±76.8 and 338.8±104.8, respectively (overall P=0.04, pairwise comparison: baseline to 6 months (P=0.1), baseline to 24 months (P=1.0)). Mean FEV1 values at baseline and at 6 and at 24 months post procedure were 0.86±0.38, 0.92±0.37 and 0.82±0.36 liters, respectively (overall P=0.003, pairwise comparison: baseline to 6 months (P=0.04), baseline to 24 months (P=0.75)). The median 6MWTD for the ECT and control groups at 24 months were 333.0 (262.5-390) and 280 (210-405), respectively (P=0.16). There was no difference in overall survival (P=0.84). Heterogenous emphysema was a significant predictor of treatment success in univariate analysis (p=0.004). CONCLUSION: Lung volume reduction with endobronchial coils may improve the exercise capacity and FEV1 of COPD patients. However, the majority of the effect was diminished after 24 months. The current state of evidence does not support regulatory approval of ECT and warrant its use only after consideration of the benefit-harm ratio in a highly selected patient population.

Vanishing lung syndrome with community-acquired pneumonia and infection of bullae.

We present a case of a 36-year old male who was a long-term smoker and was found to have giant bullous emphysema on chest imaging as an accidental finding. At the time, when his first chest CT was obtained, he was asymptomatic and was recommended to consult a pulmonologist but was lost to follow-up for a year until he presented to the emergency department with fever, dyspnea, and chest pain. He was admitted to a pulmonology department. Chest CT was performed and it revealed infected bullae containing air-fluid levels as a complication of community-acquired pneumonia. After successful antibacterial treatment, the patient was discharged and recommended to consult with a thoracic surgeon. A few months later, he had video-assisted thoracoscopic surgery and left upper lobectomy as part of definitive treatment.

Clinical Features and Outcomes of Combined Pulmonary Fibrosis and Emphysema After Lung Transplantation.

BACKGROUND: Combined pulmonary fibrosis and emphysema (CPFE) is recognized as a characteristic syndrome of smoking-related interstitial lung disease that has a worse prognosis than idiopathic pulmonary fibrosis (IPF). However, outcomes after lung transplantation for CPFE have not been reported. The aim of this study is to describe the clinical features and outcomes of CPFE after lung transplantation. RESEARCH QUESTION: What are the clinical features and outcomes of CPFE after lung transplantation? STUDY DESIGN AND METHODS: This is a single-center retrospective cohort study of patients with CPFE and IPF who underwent lung transplantation at our center between January 2011 and December 2016. We defined CPFE as ≥10% emphysema in the upper lung fields combined with fibrosis on high-resolution CT scan. We characterized the clinical features of patients with CPFE and compared their outcomes after lung transplantation with those with IPF. RESULTS: Twenty-seven of 172 (16%) patients with IPF met criteria for CPFE. Severe pulmonary hypertension was present in 16 of 27 (59%) patients with CPFE. On logistic regression analysis, CPFE was significantly associated with primary graft dysfunction (PGD) grade 3 (OR, 3.14; 95% CI, 1.18-8.37; P = .02). On competing risk regression analysis, CPFE was associated with acute cellular rejection (ACR) grade ≥ A2, and chronic lung allograft dysfunction (CLAD) (hazard ratio [HR], 1.89; 95% CI, 1.10-3.25; P = .02; HR, 1.96; 95% CI, 1.02-3.77; P = .04, respectively). Five-year survival was 79.0% for the CPFE group and 75.4% for the IPF group (log-rank P = .684). INTERPRETATION: After transplantation, patients with CPFE were more likely to develop PGD, ACR, and CLAD compared with those with IPF. However, survival was not significantly different between the two groups.

Comparison of Multiple Diagnostic Tests to Measure Dynamic Hyperinflation in Patients with Severe Emphysema Treated with Endobronchial Coils.

PURPOSE: For this study, we aimed to compare dynamic hyperinflation measured by cardiopulmonary exercise testing (CPET), a six-minute walking test (6-MWT), and a manually paced tachypnea test (MPT) in patients with severe emphysema who were treated with endobronchial coils. Additionally, we investigated whether dynamic hyperinflation changed after treatment with endobronchial coils. METHODS: Dynamic hyperinflation was measured with CPET, 6-MWT, and an MPT in 29 patients before and after coil treatment. RESULTS: There was no significant change in dynamic hyperinflation after treatment with coils. Comparison of CPET and MPT showed a strong association (rho 0.660, p < 0.001) and a moderate agreement (BA-plot, 202 ml difference in favor of MPT). There was only a moderate association of the 6-MWT with CPET (rho 0.361, p 0.024). CONCLUSION: MPT can be a suitable alternative to CPET to measure dynamic hyperinflation in severe emphysema but may overestimate dynamic hyperinflation possibly due to a higher breathing frequency.

Combined Pulmonary Fibrosis and Emphysema (CPFE) Clinical Features and Management.

BACKGROUND: Combined pulmonary fibrosis and emphysema (CPFE) is an underrecognized syndrome characterized by chronic, progressive disease with a dismal prognosis. Frequent co-morbidities with a higher incidence than in idiopathic pulmonary fibrosis or emphysema alone are pulmonary hypertension (WHO group 3) in 47-90% of the patients and lung cancer in 46.8% of the patients. OBJECTIVE: Review current evidence and knowledge concerning diagnosis, risk factors, disease evolution and treatment options of CPFE. METHODS: We searched studies reporting CPFE in original papers, observational studies, case reports, and meta-analyses published between 1990 and August 2020, in the PubMed, Embase, Cochrane Library, Wiley Online Library databases and Google Scholar using the search terms [CPFE], [pulmonary fibrosis] OR [IPF] AND [emphysema]. Bibliographies of retrieved articles were searched as well. Further inclusion criteria were publications in English, French, German and Italian, with reference to humans. In vitro data and animal data were not considered unless they were mentioned in studies reporting predominantly human data. RESULTS: Between May 1, 1990, and September 1, 2020, we found 16 studies on CPFE from the online sources and bibliographies. A total of 890 patients are described in the literature. Although male/female ratio was not reported in all studies, the large majority of patients were male (at least 78%), most of them were current or former heavy smokers. CONCLUSION: CPFE is a syndrome presenting with dyspnea on exertion followed by disruptive cough and recurrent exacerbations. The disease may progress rapidly, be aggravated by pulmonary hypertension WHO group 3 and is associated with an increased risk of lung cancer. Smoking and male sex are important risk factors. There is a need for more research on CPFE especially relating to etiology, influence of genetics, treatment and prevention options. Antifibrotic therapy might be an interesting treatment option for these patients.