Alpha-1 antitrypsin deficiency

Alpha-1 antitrypsin deficiency (AATD) is a rare hereditary condition caused by decreased plasma and tissue levels of alpha-1 antitrypsin (AAT) that can lead to serious lung and liver disease in children and adults. AATD patients face challenges such as under diagnosis, clinical variability, and limited treatment options for liver disease. Early detection and biomarkers for predicting outcomes are needed to improve patient outcome. Currently, the only approved pharmacological therapy is augmentation therapy, which can delay the progression of emphysema. However, alternative strategies such as gene therapy, induced pluripotent stem cells, and prevention of AAT polymerization inside hepatocytes are being investigated. This review aims to summarize and update current knowledge on AATD, identify areas of controversy, and formulate questions for further research.

Telemedicine in the management of chronic obstructive pulmonary disease: A systematic review

Telemedicine is defined as the use of electronic technology for information and communication by healthcare professionals with patients (or care givers) aiming at providing and supporting healthcare to patients away from healthcare institutions. This systematic review over the last decade (2013-2022) investigates the use of telemedicine in patients with chronic obstructive pulmonary disease (COPD). We identified 53 publications related to: (1) home tele-monitorization; (2) tele-education and self-management; (3) telerehabilitation; and (4) mobile health (mHealth). Results showed that, although evidence is still weak in many of these domains, results are positive in terms of improvement of health-status, use of health-care resources, feasibility, and patient satisfaction. Importantly, no safety issues were identified. Thus, telemedicine can be considered today as a potential complement to usual healthcare.

Cystic lung disease

The term cystic lung disease encompasses a heterogeneous group of entities characterised by round lung lesions that correspond to cysts with fine walls, which usually contain air. The differential diagnosis of these lesions can be challenging, requiring both clinical and radiological perspectives. Entities such as pulmonary emphysema and cystic bronchiectasis can simulate cystic disease. High-resolution computed tomography (HRCT) is the imaging technique of choice for the evaluation and diagnosis of cystic lung disease, because it confirms the presence of lung disease and establishes the correct diagnosis of the associated complications. In many cases, the diagnosis can be established based on the HRCT findings, thus making histologic confirmation unnecessary. For these reasons, radiologists need to be familiar with the different presentations of these entities. A wide variety of diseases are characterised by the presence of diffuse pulmonary cysts. Among these, the most common are lymphangioleiomyomatosis, which may or may not be associated with tuberous sclerosis, Langerhans cell histiocytosis, and lymphocytic interstitial pneumonia. Other, less common entities include Birt-Hogg-Dubé syndrome, amyloidosis, and light-chain deposit disease. This article describes the characteristics and presentations of some of these entities, emphasizing the details that can help differentiate among them.

Decreased Expression of EC-SOD and Fibulin-5 in Alveolar Walls of Lungs From COPD Patients

INTRODUCTION

The aim of this study is to analyze the expression of the main oxidant scavenger superoxide dismutase (EC-SOD), its main binding protein Fibulin-5 and several oxidative and nitrosative-derived products in the lung of COPD patients and controls.

MATERIALS AND METHODS

Lung tissue samples from 19 COPD patients and 20 control subjects were analyzed. The architecture of elastic fibres was assessed by light and electron microscope histochemical techniques, and levels of EC-SOD and fibulin-5 were analyzed by immunohistochemistry and RT-PCR. The impact of oxidative stress on the extracellular matrix was estimated by immunolocalization of 4-hydroxynonenal (4-HNE), malondialdehyde (MDA) and 3-nitrotyrosine (3-NYT) adducts.

RESULTS

Alveolar walls of COPD patients exhibited abnormal accumulations of collapsing elastic fibres, showing a pierced pattern in the amorphous component. The semiquantitative analysis revealed that COPD patients have a significantly reduced expression of both EC-SOD and fibulin-5 (0.59±0.64 and 0.62±0.61, respectively) in alveolar, bronchiolar and arteriolar walls compared to control subjects (1.39±0.63 and 1.55±0.52, respectively, p<0.05). No significant changes in mRNA levels of these proteins were observed between groups. Among the oxidation markers, malondialdehyde was the best in distinguishing COPD patients.

CONCLUSIONS

COPD patients show a reduced expression of EC-SOD and fibulin-5 in the lung interstitium. Paralleling the reduction of EC-SOD levels, the decrease of fibulin-5 expression in COPD lungs supports the hypothesis of an impaired pulmonary antioxidant response in COPD patients.

Hypermethylation of Anti-oncogenic MicroRNA 7 is Increased in Emphysema Patients

INTRODUCTION

MicroRNA-7 (miR-7) has a suppressive role in lung cancer and alterations in its DNA methylation may contribute to tumorigenesis. As COPD patients with emphysema have a higher risk of lung cancer than other COPD phenotypes, we compared the miR-7 methylation status among smoker subjects and patients with various COPD phenotypes to identify its main determinants.

METHODS

30 smoker subjects without airflow limitation and 136 COPD patients without evidence of cancer were recruited in a prospective study. Clinical and functional characteristics were assessed and patients were classified into: frequent exacerbator, emphysema, chronic bronchitis and asthma COPD overlap (ACO). DNA collected from buccal epithelial samples was isolated and bisulfite modified. miR-7 methylation status was evaluated by quantitative methylation-specific polymerase chain reaction (qMSP).

RESULTS

miR-7 Methylated levels were higher in COPD patients than in smokers without airflow limitation (23.7±12.4 vs. 18.5±8.8%, p=0.018). Among COPD patients, those with emphysema had higher values of methylated miR-7 (27.1±10.2%) than those with exacerbator (19.4±9.9%, p=0.004), chronic bronchitis (17.3±9.0%, p=0.002) or ACO phenotypes (16.0±7.2%, p=0.010). After adjusting for clinical parameters, differences between emphysematous patients and those with other phenotypes were retained. In COPD patients, advanced age, mild-moderate airflow limitation, reduced diffusing capacity and increased functional residual capacity were identified as independent predictors of methylated miR-7 levels.

CONCLUSION

The increase of miR-7 methylation levels experienced by COPD patients occurs mainly at the expense of the emphysema phenotype, which might contribute to explain the higher incidence of lung cancer in these patients.

Acute Exacerbation According to GOLD 2017 Categories in Patients with Chronic Obstructive Pulmonary Disease

INTRODUCTION

The association between GOLD categorizations and future exacerbations has not been fully investigated. This study elucidates whether the GOLD 2017 classification is associated with different future exacerbation risk in patients with chronic obstructive pulmonary disease (COPD) compared with the previous GOLD categorization. Another objective was to investigate the impacts of the symptoms and FEV1 on the predicted future exacerbation independently of previous exacerbation history.

METHODS

We analyzed patients from three prospective COPD cohorts (SNUH, KOCOSS, and KOLD) and evaluated the risk of moderate to severe exacerbation among different models, including GOLD grade (FEV1), GOLD 2011, and GOLD 2017.

RESULTS

In total, 611 COPD patients were included (36 from SNUH, 257 from KOCOSS, and 318 from KOLD). GOLD 2017 classification, excluding FEV1% for categorization criteria, showed no differences in future exacerbation risk compared with GOLD grade and GOLD 2011 based on c-statistics. Among those with no frequent exacerbation history and FEV1 ≥50%, the group with more symptoms was significantly associated with future exacerbations than the group with less symptoms. A lower FEV1 (FEV1 <50%) was not associated with a higher future exacerbation risk than a higher FEV1 (FEV1 ≥50%), regardless of prior exacerbation history and symptom group.

CONCLUSION

The GOLD 2017 classification was not different from GOLD grade and GOLD 2011 regarding the association with future exacerbation risk, and there were no significant differences in exacerbation risk according to FEV1%. This suggests that FEV1 might not be an important factor in future exacerbation risk. These results partly support the GOLD 2017 assessment tool.

Lack of Correlation Between Pulmonary and Systemic Inflammation Markers in Patients with Chronic Obstructive Pulmonary Disease: A Simultaneous, Two-Compartmental Analysis

INTRODUCTION

The origin of systemic inflammation in chronic obstructive pulmonary disease (COPD) patients remains to be defined, but one of the most widely accepted hypothesis is the 'spill over' of inflammatory mediators from the lung to the circulation.

OBJECTIVE

To evaluate the relationship between pulmonary and systemic inflammation in COPD quantifying several inflammatory markers in sputum and serum determined simultaneously.

METHODOLOGY

Correlations between various inflammatory variables (TNF-α, IL6, IL8) in sputum and serum were evaluated in 133 patients from the PAC-COPD cohort study. A secondary objective was the evaluation of relationships between inflammatory variables and lung function.

RESULTS

Inflammatory markers were clearly higher in sputum than in serum. No significant correlation was found (absolute value, r=0.03-0.24) between inflammatory markers in blood and in sputum. There were no significant associations identified between those markers and lung function variables, such as FEV1, DLCO and PaO2 neither.

CONCLUSIONS

We found no correlation between pulmonary and systemic inflammation in patients with stable COPD, suggesting different pathogenic mechanisms.

The early detection of lung cancer during follow-up of patients undergoing endobronchial one-way valve treatment for emphysema

We describe the early detection of lung cancer during the follow-up of two emphysematous patients undergoing endobronchial treatment with one-way valves for severe dyspnea. In both cases, the lung function improvement achieved after the valves placement allowed their surgical treatment. In additional to standard follow-up for evaluating the progression of emphysema, such patients should be enrolled in a screening program. It may allow the early detection of lung cancer with the possibility for surgery in accordance with respiratory function of patient.

Animal models of chronic obstructive pulmonary disease

Animal models of disease have always been welcomed by the scientific community because they provide an approach to the investigation of certain aspects of the disease in question. Animal models of COPD cannot reproduce the heterogeneity of the disease and usually only manage to represent the disease in its milder stages. Moreover, airflow obstruction, the variable that determines patient diagnosis, not always taken into account in the models. For this reason, models have focused on the development of emphysema, easily detectable by lung morphometry, and have disregarded other components of the disease, such as airway injury or associated vascular changes. Continuous, long-term exposure to cigarette smoke is considered the main risk factor for this disease, justifying the fact that the cigarette smoke exposure model is the most widely used. Some variations on this basic model, related to exposure time, the association of other inducers or inhibitors, exacerbations or the use of transgenic animals to facilitate the identification of pathogenic pathways have been developed. Some variations or heterogeneity of this disease, then, can be reproduced and models can be designed for resolving researchers' questions on disease identification or treatment responses.

Recombinant Human Keratinocyte Growth Factor Induces Akt Mediated Cell Survival Progression in Emphysematous Mice

INTRODUCTION

Emphysema has been associated with decreased VEGF and VEGFR-2 expression and the presence of high numbers of apoptotic alveolar cells. Keratinocyte growth factor stimulates VEGF synthesis which in turn confers normal lung structure maintenance via the Akt pathway. In this study the potential role of rHuKGF in the improvement of deregulated Akt mediated cell survival pathway in emphysematous mice was investigated.

METHODS

Three experimental groups, i.e., emphysema, treatment and control groups, were prepared. Lungs of mice were treated on 3 occasions by oropharyngeal instillation of 10mg rHuKGF per kg body weight after induction of emphysema with porcine pancreatic elastase. Subsequently, lung tissues from mice were collected for histopathology and molecular biology studies.

RESULTS AND DISCUSSION

Histopathology photomicrographs and destructive index analysis have shown that elastase-induced airspace enlargement and loss of alveoli recovered in the treatment group. rHuKGF stimulates VEGF production which in turn induces the Akt mediated cell survival pathway in emphysematous lungs. mRNA expression of VEGF, VEGFR, PI3K and Akt was significantly increased while Pten, Caspase-9 and Bad was notably decreased in treatment group when compared with emphysema group, being comparable with the control group. Moreover, VEGF protein expression was in accordance with that found for mRNA.

CONCLUSION

Therapeutic rHuKGF supplementation improves the deregulated Akt pathway in emphysema, resulting in alveolar cell survival through activation of the endogenous VEGF-dependent cell survival pathway. Hence rHuKGF may prove to be a potential drug in the treatment of emphysema.

[Congenital lobar hyperinflation: conservative management as an alternative therapy]

Congenital lobar emphysema used to be treated surgically. Congenital lobar hyperinflation is the currently recommended term, as it involves pathologically healthy lung tissue, which is why conservative management may be an option. Four cases of diagnosed congenital lobar hyperinflation are presented in which conservative treatment was chosen due to their clinical stability. Their outcome has been satisfactory with progressively normal radiology.