Questions relating to premenstrual asthma

The study of asthma in fertile women needs to consider its potentially recurrent exacerbation in a specific phase of the menstrual cycle. Premenstrual asthma (PMA) refers to the deterioration of asthma in some women of fertile age during the premenstrual phase. Prevalence varies considerably according to studies (11%-47.44%) mainly because there is no standardized definition of the illness. There is a possible link between PMA and premenstrual syndrome, which is a set of physical and psychic manifestations that occur in some fertile women during the same premenstrual phase. This relation has been widely studied but there are still several unknowns. PMA etiopathogeny is not known. It involves possible causes such as hormonal variations in the premenstrual phase, the coexistence of atopy, variations during the cycle in substances related to inflammation, like LTC4 leukotrienes, catecholamines, E2 and F2α prostaglandins and certain cytokines. Also considered are psychological factors related to this phase of the menstrual cycle, a high susceptibility to infection or increased bronchial hyperreactivity prior to menstruation. Yet no factor fully explains its etiology, consequently no specific treatment exists. Researchers have investigated hormones, anti-leukotrienes, prostaglandin synthesis inhibitors, diuretics, phytoestrogens and alternative therapies, but none has been shown to be effective.

Unresectable stage III non-small-cell lung cancer: Have we made any progress?

Lung cancer is responsible for the most cancer deaths worldwide with an incidence that is still rising. One third of patients have unresectable stage IIIA or stage IIIB disease. The standard of care for locally advanced disease in patients with good performance status consists of combined modality therapy in particular concurrent chemoradiotherapy. But despite a lot of efforts done in the past, local control and survival of patients with unresectable stage III non-small-cell lung cancer (NSCLC) remains poor. Improving outcomes for patients with unresectable stage III NSCLC has therefore been an area of ongoing research. Research has focused on improving systemic therapy, improving radiation therapy or adding a maintenance therapy to consolidate the initial therapy. Also implementation of newer targeted therapies and immunotherapy has been investigated as well as the option of prophylactic cranial irradiation. This article reviews the latest literature on improving local control and preventing distant metastases. It seems that we have reached a plateau with conventional chemotherapy. Radiotherapy dose escalation did not improve outcome although increasing radiation dose-intensity with new radiotherapy techniques and the use of newer agents, e.g., immunotherapy might be promising. In the future well-designed clinical trials are necessary to prove those promising results.

Von Hippel-Lindau protein and respiratory diseases

Von Hippel-Lindau protein (pVHL) was first identified as a tumor suppressor gene as mutations in the VHL gene predispose individuals to systemic benign or malignant tumors and cysts in many organs, including renal cell carcinoma of the clear-cell type and hemangioblastoma. Although pVHL is best known to act as a component of ubiquitin protein ligase for the proteasomal degradation of hypoxia inducible factor (HIF)-α, pVHL also interacts with extracellular matrix proteins and cytoskeleton, regulating extracellular matrix assembly, cell signaling, and many other cellular functions. Recent studies suggest that pVHL contributes to many lung diseases, including pulmonary arterial hypertension, lung cancer, pulmonary fibrosis, and acute respiratory distress syndrome. Mutation or loss of function of pVHL activates HIF and induced expression of vascular endothelial growth factor, endothelin-1, and FoxM1, leading to pulmonary arterial hypertension. Loss of pVHL in lung cancer cells promotes epithelial-mesenchymal transition and cancer migration and invasion while decreasing lung cancer cell proliferation and colonization. In patients of idiopathic pulmonary fibrosis, elevated expression of pVHL induces expression of fibronectin/integrin α5β1/focal adhesion kinase signaling, resulting in fibroproliferation and fibrosis. In alveolar epithelial cells, pVHL mediates Na-K-ATPase degradation in an HIF independent pathway, causing decreased edema clearance during hypoxia. These studies suggest that pVHL plays key roles in the pathogenesis of many lung diseases, and further investigations are warranted to elucidate the underlying molecular mechanisms.

Bilateral pulmonary nodular amyloidosis: A case report and review of the literature

Pulmonary amyloidosis is uncommon and is usually associated with systemic amyloidosis. Localized pulmonary involvement in amyloidosis without systemic amyloidosis is even rarer; it is generally tracheobronchial or parenchymal in location. Parenchymal pulmonary amyloidosis is generally asymptomatic and an incidental finding, presenting as nodules varying in size and number, unilateral or bilateral. We present an unusual case of primary bilateral pulmonary nodular amyloidosis in an elderly female.

Role of p53 in lung tissue remodeling

The tumor suppressor gene p53 regulates a wide range of cellular processes including cell cycle progression, proliferation, apoptosis and tissue development and remodeling. Lung cell apoptosis and tissue remodeling have critical roles in many lung diseases. Abnormal proliferation or resistance to apoptosis of lung cells will lead to structural changes of many lung tissues, including the pulmonary vascular wall, small airways and lung parenchyma. Among the many lung diseases caused by vascular cell apoptosis and tissue remodeling are chronic obstructive pulmonary disease, bronchial asthma and pulmonary arterial hypertension. Recent advances in biology and medicine have provided new insights and have resulted in new therapeutic strategies for tissue remodeling in human and animal models. This review is focused on lung disease susceptibility associated with the p53 pathway and describes molecular mechanisms upstream and downstream of p53 in lung tissue remodeling. Improved understanding of structural changes associated with pulmonary vascular remodeling and lung cell apoptosis induced by the p53 pathway may new provide therapeutic targets.

Asthma-chronic obstructive pulmonary disease overlap syndrome: A diagnostic puzzle for the clinicians

Although asthma and chronic obstructive pulmonary disease (COPD) are distinct airway diseases characterized by chronic inflammation, in some cases distinguishing between them is puzzling. For example, chronic smoking leads asthmatic inflammation to a differentiated pattern resembling the COPD inflammation, and in some cases to fixed obstruction as in COPD, and on the other hand, few COPD patients may present with airway reversibility. ACOS is the condition sharing features encountered both in asthma and COPD. Asthma-COPD overlap syndrome (ACOS) represents a diagnostic challenge in the clinical practice, since there is lack of specific indicators to distinguish it from asthma or COPD, and moreover, genetic risk factors, underlying pathology and molecular pathways, clinical characteristics, therapeutic interventions, response to treatment and prognosis are poorly described. The management of ACOS is recommended to be individualized and should target on the maximum effectiveness with the least side effects. Combination therapy with ICS/LABA or LAMA, or newly developed specific anti-eosinophil therapies and treatments specifically targeting neutrophils might be of relevance in the management of ACOS, but studies are needed in order to assess the response and prognosis. Based on the current knowledge about ACOS thus far, it would be recommended that we approached chronic obstructive airway disease rather by describing than by classifying the disease; this would allow us to have a picture that better describes the disease and to implement an individualized therapeutic approach, according to the custom phenotype. Nevertheless, more studies are needed in order to clarify several important issues with regard to ACOS, such as the genetic risk factors for developing ACOS, the links between genotype and phenotype, the molecular pathways and underlying mechanisms of ACOS, the identification of possible specific biomarkers for diagnosis and targeted treatment, the optimal therapeutic interventions, and finally, the prognosis of ACOS.

Gastroesophageal reflux disease related asthma: From preliminary studies to clinical practice

The diagnosis of asthma requires the presence of episodic respiratory difficulties characterized by variable and reversible airway obstruction. It has a high prevalence worldwide and is traditionally considered to be an allergic disease. Most cases are responsive to treatment with bronchodilators and anti-inflammatories, as recommended by national and international guidelines; however, approximately 10% of asthmatic patients are refractory even to optimal therapy. Gastroesophageal reflux disease (GERD) is a common disorder in asthmatic patients and the two disorders may be linked pathophysiologically. Here we review data from preliminary studies that suggest asthma could be induced or exacerbated by gastroesophageal reflux. The optimal strategies for the diagnosis of GERD-related asthma and its therapy are still debated. However, there is evidence to suggest that antireflux treatment is effective and practical for asthmatic patients with well-defined reflux disease.

Update on diagnosis and treatment of pulmonary alveolar microlithiasis

Pulmonary alveolar microlithiasis (PAM) (MIM265100) is a rare disease characterized by the diffuse deposit of microlithiasis in alveolar spaces. PAM could occur worldwide with high prevalence in Asia and Europe. Familial occurrence indicates its autosomal recessive trait and the SLC34A2 gene was identified as the responsible gene for the disease. In spite of the versatile mutation sites in patients from other countries, exon 7 and exon 8 might be the most liable gene in Chinese and Japanese patients. Most mutations caused the premature termination of proteins and produced truncated proteins, leading to the blocking of the recycling and degrading of outdated surfactant which is full of phospholipids. The most outstanding clinical feature of PAM is the discrepancy between the paucity of symptoms and the degree of pulmonary involvement. Diagnosis is easy to establish based on typical chest radiograph image and nuclear medicine improves its early diagnosis and active evaluation. Pathology of the unique intra-alveolar lamellar microliths gives strong support for diagnosis. No effective treatment is considered valid currently. However, lung transplantation is effective for advanced-stage patients, and long term treatment of disodium etidronate seems promising.

Pulmonary effects of intermittent, seasonal exposure to high concentrations of cotton dust

AIM: To quantify the exposure levels and to assess pulmonary reactions associated with exposure to cotton dust and its biological contaminants.

METHODS: All employees (51 male workers) of a ginning industry as well as 51 referent unexposed subjects from clerical staff of an educational center were investigated. Atmospheric concentrations of cotton dust and bioaerosols were measured. Furthermore, bacterial and fungal genera and species were identified by an expert microbiologist and an experienced mycologist. A standard respiratory symptom questionnaire was filled out for the subjects and they underwent multiple spirometry tests, at the beginning and at the end of work season as well as prior to (pre-exposure base line values) and at end of the first shift of workweek (post exposure).

RESULTS: Gram negative bacteria including Enterobacter agglomerans and Pseudomonas spp. were found to be the dominant bacterial species and genera, respectively. Similarly, dominant fungi were identified to be Mucor sp. Rhizopus sp. and Aspergillus niger. Mean atmospheric concentrations of cotton dust in ginning and outdoor areas were found to be 35.2 and 6.8 mg/m³, respectively. The prevalence rates of cough, phlegm, wheezing, dyspenea and grade 1/2 byssinosis among the exposed subjects were significantly higher than their corresponding values for the unexposed employees (P < 0.05). Additionally, significant differences were noted in the mean baseline value (preshift) of vital capacity, forced expiratory volume in the first second (FEV1) and FEV1/forced vital capacity ratio of the exposed subjects when compared with those of their referent counterparts. Similarly, significant cross shift decrements were noted in most parameters of pulmonary function of the exposed subjects.

CONCLUSION: Seasonal exposure to cotton dust induces both acute, partially reversible, and chronic irreversible decrements in the lungs’ functional capacities as well as increased prevalence of respiratory symptoms.

SARS-CoV-2 with concurrent coccidioidomycosis complicated by refractory pneumothorax in a Hispanic male: A case report and literature review

BACKGROUND

The incidence of secondary coinfections particularly fungal infections among severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not well described. Little is known of the complications that could be encountered in such conditions.

CASE SUMMARY

A 50-year-old Hispanic male who was a prior smoker presented with shortness of breath. He was diagnosed with SARS-CoV-2. He improved and was discharged with home oxygen. A month later, he presented with sudden onset cough and shortness of breath. Chest X-ray showed development of right-sided tension pneumothorax, right pleural effusion and an air-filled cystic structure. Computed tomography thorax showed findings suggestive of pulmonary coccidioidomycosis. Coccidioides antigen was positive, and fluconazole was initiated. For pneumothorax, a pigtail catheter was placed. The pigtail chest tube was later switched to water seal, unfortunately, the pneumothorax re-expanded. Another attempt to transition chest tube to water seal was unsuccessful. Pigtail chest tube was then swapped to 32-Fr chest tube and chemical pleurodesis was performed. This was later transitioned successfully to water seal and finally removed. He was discharged on a four-week oral course of fluconazole 400 mg and was to follow up closely as an outpatient for continued monitoring.

CONCLUSION

Pneumothorax is associated with a worse prognosis, especially with comorbidities such as diabetes, immunosuppression and malignancy. Suspicion for concomitant fungal infection in such patients should be high and would necessitate further investigation.

Role of hydrogen sulphide in airways

The toxicity of hydrogen sulfide (H₂S) has been known for a long time, as it is prevalent in the atmosphere. However accumulative data suggest that H₂S is also endogenously produced in mammals, including man, and is the third important gas signaling molecule, besides nitric oxide and carbon monoxide. H₂S can be produced via non enzymatic pathways, but is mainly synthesized from L-cysteine by the enzymes cystathionine-γ-lyase, cystathionine-β-synthetase, cysteine amino transferase and 3-mercaptopyruvate sulfurtransferase (3MTS). The formation of H₂S from D-cysteine via the enzyme D-amino acid oxidase and 3MTS has also been described. Endogenous H₂S not only participates in the regulation of physiological functions of the respiratory system, but also seems to contribute to the pathophysiology of airway diseases such as chronic obstructive pulmonary disease, asthma and pulmonary fibrosis, as well as in inflammation, suggesting its possible use as a biomarker for these diseases. This review summarizes the different implications of hydrogen sulfide in the physiology of airways and the pathophysiology of airway diseases.

Seasonal variation and living alone are related to pulmonary rehabilitation non-completion

AIM: To identify baseline characteristics that independently predict pulmonary rehabilitation non-completion and compare these findings against the participant’s reasons for non-completion.

METHODS: Participants with chronic obstructive pulmonary disease (COPD) who attended a standardised twice weekly, eight week pulmonary rehabilitation program (located in the sub-tropics, latitude 27°29’ South) between 2010 and 2012 were recruited. The baseline characteristics of program completers and non-completers were compared in a case-controlled design. Participants who attended < 12/16 sessions were classified as a non-completer. Non-completers (those who missed > 4 sessions of the program) were asked by one independent investigator to participate in a survey about their pulmonary rehabilitation experience. Baseline characteristics were assessed for differences between program completers and non-completers. The baseline characteristics included disease severity, exercise capacity, smoking history, participant’s social support and the season when each participant commenced rehabilitation. Non-completers that agreed to participate in the survey were asked to indicate what personal factors or external factors contributed to their program non-completion. Comparisons of completers and non-completers baseline characteristics were performed using cross-tabulations and t-tests, with significant measures analysed in a multivariate binary logistic regression model. Non-completers survey responses were compared to the identified independent predictors using cross-tabulations.

RESULTS: Twenty-six participants (23.4%) of the 111 participants with COPD [(mean ± SD) age was 67.4 ± 9.2 years and FEV1 54.6% ± 22.3%)], were classified as non-completers. Forty-five participants (40.5%) commenced pulmonary rehabilitation during winter. Thirty-six participants (32.4%) were living alone at program commencement. In the multivariate analysis (n = 111), only programs that commenced in winter (Exp B: 0.255, 95%CI: 0.090-0.727, P = 0.011) and participants that lived alone (Exp B: 2.925, 95%CI: 1.039-8.229, P = 0.042) were identified as independent predictors of program non-completion. Twenty participants of the twenty-six non-completers agreed to participate in the survey about their pulmonary rehabilitation experience. The reasons given for non-completion were grouped into: medical reasons (75%), other personal reasons (30%) and external barriers (45%), with ten non-completers reporting more than one reason. No participant reported living alone or that the program commenced during winter as a reason for non-completion. There was no relationship between illness being the participant’s reason for non-completion and the programs that commenced in winter (P = 0.135).

CONCLUSION: Despite winter commencing programs and participants who lived alone being independent predictors of program non-completion, neither measure was reported by participants as a reason for non-completion.

Personalising exacerbation prediction strategies in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality and morbidity worldwide. One of the most important features of this disease is exacerbations where a patient’s respiratory symptoms episodically worsen. Exacerbations accounted for over 140000 hospital admissions in 2012 in the United Kingdom with considerably more exacerbations being treated in primary care. Despite significant research in this area in recent years, treatment of acute exacerbations in the community remains limited to oral glucocorticoids, antibiotics and bronchodilators. One of the issues with unpicking the complexity of exacerbations is trying to find out the exact underlying cause and mechanism that leads to symptoms and lung destruction. Currently symptoms are initially guided by symptoms alone though multiple causes of exacerbations have common presentations. This includes viral and bacterial infections and episodes relating to environmental triggers such as pollen and pollution. There is also evidence that cardiovascular factors can contribute to symptoms of breathlessness that can mimic COPD exacerbations. In this editorial we discuss recent advances in the use of precision medicine to more accurately treat exacerbations of COPD. This includes identification of phenotypes that could help rationalise treatment and more importantly identify novel drug targets. We also consider the future role of precision medicine in preventing exacerbations and identifying COPD patients that are at increased risk of developing them.

Cytokine gene polymorphisms in idiopathic pulmonary fibrosis

AIM: To characterize cytokine gene polymorphisms in patients with idiopathic pulmonary fibrosis (IPF) compared to healthy controls.

METHODS: Fifty-six IPF patients were involved in the study. The control population consisted of 144 healthy volunteers without history of lung disease. All of the patients were diagnosed with IPF according to the American Thoracic Society/European Respiratory Society consensus statement. Polymorphisms in the interleukin (IL)-1, IL-1, IL-1R, IL-1RA, IL-2, IL-4, IL-6, IL-10, IL-12, tumour necrosis factor, interferon, transforming growth factor, IL-1, IL-2, IL-4 and IL-4RA genes were characterized by polymerase chain reaction with sequence-specific primers. Statistical analysis was performed using the MedCalc statistical software. A Bonferroni correction of significance at an alpha of 0.05 was used for multiple analyses. A corrected P value less than 0.0023 (0.05/22) was considered significant.

RESULTS: We found significant differences in the IL-4 promoter region polymorphisms between IPF patients and controls. Namely, polymorphisms of IL-4 (-590) [computed tomography (CT) in 32 of 56 patients vs 27 of 144 controls; P < 0.0001] and IL-4 (-33) (CT in 25 of 56 patients vs 27 of 144 controls; P = 0.0006) differed between both groups. With regard to haplotypes, we found differences in the frequencies for haplotype 1 of IL-4 (-1098) (-590) (-33) between IPF and controls (TCC in 23 of 56, TTC in 10 of 56, and TTT in 21 of 56 patients vs TCC in 112 of 144, TTC in 0 of 144, and TTT in 32 of 144 controls; P < 0.0001). We did not find significant differences in gene polymorphism frequencies of other cytokines in the IPF group vs the controls.

CONCLUSION: We hypothesize that IL-4 promoter polymorphisms could be involved in the pathogenesis of IPF, likely via enhancement of the T_h2 cytokine milieu with exaggerated fibroproliferative healing.

Management of recurrent malignant pleural effusions with a tunneled indwelling pleural catheter

In this review, we report on the use of indwelling pleural catheters in the treatment of malignant pleural effusions. We describe the most commonly used catheter. Also, treatment with indwelling pleural catheters as compared to talc pleurodesis is reviewed. A comparison of efficacy, costs, effects on quality of life, and complications is made. Only one randomized controlled trial comparing the two is available up to date, but several are underway. We conclude that treatment for malignant pleural effusions with indwelling pleural catheters is a save, cost-effective, and patient-friendly method, with low complication rates.

Collagen vascular disease-associated interstitial lung disease

Interstitial lung disease (ILD) is an important manifestation of collagen vascular diseases. It is a common feature of scleroderma, and also occurs in dermatomyositis and polymyositis, mixed connective tissue disease, Sjogren’s syndrome, rheumatoid arthritis, systemic lupus erythematosus, and Antineutrophil cytoplasmic antibody-associated vasculitis. When present, it is associated with increased morbidity and mortality, thus making early diagnosis important. In fact, in many patients, ILD may be the first manifestation of a collagen vascular disease. The most common symptoms are cough and dyspnea. The diagnosis is made based on pulmonary function tests showing restrictive lung disease and impaired oxygen diffusion and chest imaging showing ground glass infiltrates, interstitial thickening, and/or fibrosis. The most common histologic finding on lung biopsy is non-specific interstitial pneumonia, though organizing pneumonia and usual interstitial pneumonia may also be seen. Treatment is focused on addressing the underlying collagen vascular disease with immunosuppression, either with corticosteroids or a steroid-sparing agent such as cyclophosphamide, azathioprine, or mycophenolate, although the optimal agent and duration of therapy is not known. There are few clinical trials to guide therapy that focus specifically on the progression of ILD. The exception is in the case of scleroderma-associated ILD, where cyclophosphamide has been shown to be effective.

Causes of failure in acute respiratory distress syndrome modeling and treatment in animal research and new approaches

Acute respiratory distress syndrome (ARDS) is a major cause of morbidity, death and cost in intensive care units. Despite intensive research, pharmacotherapy has not passed the experimental stage and mortality rates are still high. Animal models provide a bridge between patients and the laboratory bench. Different animal models have been developed in order to mimic human ARDS, but they have limitations. The purpose of this review was to summarize the properties of the most commonly used experimental animal models mimicking the causes and pathology of human ARDS, the limitations of ARDS models, treatment failure and new therapeutic approaches.

EGFR mutation identifies distant squamous cell carcinoma as metastasis from lung adenocarcinoma

Lung cancer metastasis is typically determined by histologic similarity between distant and primary lesions. Herein, we present a 70-year-old Japanese woman with an adenocarcinoma in her lung and a squamous cell carcinoma in her femur; both tumors had an identical epidermal growth factor receptor mutation, G719S. This indicated that both tumors had a common origin, despite their histologic dissimilarity. The tumor in the femur was thus identified genetically as a lung cancer metastasis. This case suggests that genetic analysis can determine whether a distant lesion is a lung cancer metastasis, particularly when the histology differs from that of the primary lesion.

Multicenter cooperative observational study of idiopathic pulmonary fibrosis with non-small cell lung cancer

AIM: To research the natural course of idiopathic pulmonary fibrosis (IPF) with advanced non-small cell lung cancer (NSCLC) and the association between acute exacerbation (AE) of IPF and chemotherapy (CT).

METHODS: From May 2007 through April 2011, 17 CT naive patients with IPF and advanced NSCLC were enrolled. Patients were classified into best supportive care (BSC) group or CT group based on the patient’s preference. Patients in the CT group received carboplatin (CBDCA) (AUC 5-6) plus paclitaxel (PTX) (175-200 mg/m²) on day 1 of each 21-d cycle as first-line therapy.

RESULTS: All patients but one chose the CT group. In the CT group, the objective response rate was 38%. The most frequent toxicity ≥ grade 3 was neutropenia (88%). Two patients (12.5%) developed AE-IPF. The median progression-free survival, the median survival time and the 1-year survival rate were 4.1 mo, 8.7 mo and 35%, respectively. Second-line CT-related AE and CT-unrelated AE occurred in 2 and 3 patients (1: BSC group; 2: CT group), respectively. Seven (41%) of all patients developed AE-IPF throughout the clinical course, and 6 of 7 patients with AE-IPF died within one month.

CONCLUSION: The incidence of AE-IPF was higher among IPF patients with advanced NSCLC than among those without NSCLC. CBDCA plus PTX regimen was tolerable and effective. However, AE-IPF has a fatal toxicity with or without CT in IPF patients with advanced NSCLC.

What is the purpose of launching World Journal of Respirology?

Congratulations to the publisher, members of the editorial board of the journal, and all the authors and readers for launching the World Journal of Respirology (WJR). The WJR is a peer-reviewed journal that will report novel theories, methods and techniques for the prevention, diagnosis, treatment, rehabilitation and nursing of patients with respiratory disease. Some of the topics that will be covered in the journal include diagnostic imaging, respiratory physiology, respiratory endoscopy, respiratory system tumors, chronic obstructive pulmonary disease, bronchial asthma, respiratory infections, critical respiratory illness, sleep-related respiratory disorders, interstitial lung disease, pulmonary vascular diseases, pulmonary embolism, traditional medicine, integrated Chinese and Western medicine, evidence-based medicine, epidemiology and nursing. Importantly, the WJR is an online, open-access journal, which will enable it to reach both experts and the general public without the need for registration or payment. If you want to share your work and findings, you will find the WJR an excellent journal for your publications!

Solitary pituitary metastasis resulting from pulmonary large cell neuroendocrine carcinoma

Solitary pituitary metastasis is a rare phenomenon in human neoplasms. We report a case of lung cancer with the initial manifestation of endocrinopathy resulting from pituitary metastasis. The patient’s initial diagnosis was a poorly differentiated carcinoma, however, morbid anatomy revealed a definite diagnosis of large cell neuroendocrine carcinoma (LCNEC). Clinical physicians should be aware of potential initial manifestations such as endocrine abnormalities including panhypopituitarism and diabetes insipidus due to solitary pituitary metastasis. This case demonstrates that an endocrine abnormality such as panhypopituitarism could be an initial manifestation of LCNEC.

Bronchial hyperresponsiveness in childhood: A narrative review

Bronchial hyperresponsiveness (BHR) is an important but not asthma-specific characteristic and can be assessed by direct and indirect methods, based on the stimulus causing airway obstruction. BHR has been proposed as a prognostic marker of asthma severity and persistence, and may also be used to control pharmacological management of asthma. The most recent data on the prevalence and development of BHR in childhood and its predictive value for subsequent asthma development in late adolescence and adulthood is discussed in this review. According to the BHR-related scientific articles written in the English language and indexed in the publicly searchable PubMed database, the prevalence of BHR varies based upon the methods used to assess it and the population examined. In general, however, BHR prevalence is reduced as children grow older, in both healthy and asthmatic populations. While asthma can be predicted by BHR, the predictive value is limited. Reduced lung function, allergic sensitization, female sex, and early respiratory illness have been identified as risk factors for BHR. The collective studies further indicate that BHR is a dynamic feature related to asthma, but asymptomatic BHR is also common. Ultimately, the prevalence of BHR varies depending on the population, the environment, and the evaluation methods used. While both the methacholine challenge and the exercise test may predict asthma in adolescence or early adulthood, the predictive value is higher for the methacholine challenge compared to the exercise test. The collective data presented in the present study demonstrate how BHR develops through childhood and its relation to bronchial asthma.

Role of chronic obstructive pulmonary disease in lung cancer pathogenesis

Chronic obstructive pulmonary disease (COPD) and lung cancer are two important smoking related conditions. However, COPD has been shown to be an independent risk factor for lung cancer regardless of smoking history, suggesting that COPD and lung cancer may share a common pathogenesis. This review summarizes the epidemiology of lung cancer and COPD briefly, as well as discussing the potential for shared genetic risk, and shared genomic mechanisms, such as epigenetic changes or DNA damage induced by smoking. How key areas of COPD pathogenesis, such as inflammation, oxidative stress and protease imbalance may contribute to subsequent development of cancer will also be covered. Finally the possibility that consequences of COPD, such as hypoxia, influence carcinogenesis will be reviewed. By understanding the pathogenesis of COPD and lung cancer in detail it is possible that new treatments may be developed and the risk of lung cancer in COPD may be reduced.

Pulmonary arterial hypertension confirmed by right heart catheterization following COVID-19 pneumonia: A case report and review of literature

BACKGROUND

Pulmonary arterial hypertension (PAH) is a disease of the arterioles resulting in an increased resistance in pulmonary circulation with associated high pressures in the pulmonary arteries, causing irreversible remodeling of the pulmonary arterial walls. Coronavirus disease 2019 (COVID-19) has been associated with development of new onset PAH in the literature leading to symptoms of dyspnea, cough and fatigue that persist in spite of resolution of acute COVID-19 infection. However, the majority of these cases of COVID related PAH were diagnosed using echocardiographic data or via right heart catheterization in mechanically ventilated patients.

CASE SUMMARY

Our case is the first reported case of COVID related PAH diagnosed by right heart catheterization in a non-mechanically ventilated patient. Right heart catheterization has been the gold standard for diagnosis of pulmonary hypertension. Our patient had right heart catheterization four months after her initial COVID-19 infection due to persistent dyspnea.

CONCLUSION

This revealed new onset PAH that developed following her infection with COVID-19, an emerging sequela of the infection

Automated weaning from mechanical ventilation

Mechanical ventilation (MV) is one of the lifesaving techniques applied to critically ill patients at bedside. However, some complications, such as ventilator-induced lung injury and ventilator-associated pneumonia, may occur in a patient undertaking MV and are often related to the duration of MV. Some written protocols have been proposed to reduce the risk of such complications, but they can be time consuming, leading to fluctuation in protocol implementation and compliance. Moreover, written instructions tend to be general and thus cannot cover all possible scenarios, resulting in variable interpretation of the protocol. To overcome these limiting factors, protocols have been computerized and there is convincing evidence in the literature showing that computerized protocols benefit management of the process and reduce the time a patient spends under MV. QuickWean is a computer-aided weaning protocol implemented on the Hamilton S1 ventilator (Hamilton Medical AG, Bonaduz, Switzerland), which guides the patient through the weaning process without requiring any intervention by the treating physician. The fully-automated ventilation mode is INTELLiVENT^®-ASV (Hamilton Medical AG), which is set according to the patient’s respiratory mechanics, patient-ventilator interaction, peripheral oxygen saturation (SpO₂) and pulmonary end-tidal carbon dioxide (PetCO₂). The INTELLiVENT^®-ASV mode sets automatically each minute to provide accurate ventilation, pressure support, fraction of inspired oxygen and positive end-expiratory pressure based on the patient’s needs. QuickWean can be pre-set to match the established weaning policy of an intensive care unit as well as being customized to a patient’s needs. It provides a progressive reduction of respiratory support, and guides the patient through the spontaneous breathing trial (SBT). At the end of the SBT, the ventilator re-starts the previous ventilation support and provides a report of the successful SBT. During all phases, PetCO₂, SpO₂ and all breathing parameters are monitored. This new automated weaning tool may improve the safety and effectiveness of an SBT, reducing the time spent in the process of weaning and providing a lower workload for the treating physician.