A Practical Approach to Severe Asthma in Children

Aspergillus Sensitization and Allergic Bronchopulmonary Aspergillosis in Asthmatic Children: A Systematic Review and Meta-Analysis

Background: The prevalence of aspergillus sensitization (AS) and allergic bronchopulmonary aspergillosis (ABPA) in asthmatic children remains unclear. Objective: To systematically review the literature to estimate the prevalence of AS and ABPA in children with bronchial asthma. Methods: We searched the PubMed and Embase databases for studies reporting the prevalence of AS or ABPA in pediatric asthma. The primary outcome was to assess the prevalence of AS, while the secondary outcome was to evaluate the prevalence of ABPA. We pooled the prevalence estimates using a random effects model. We also calculated the heterogeneity and publication bias. Results: Of the 11,695 records retrieved, 16 studies with 2468 asthmatic children met the inclusion criteria. Most studies were published from tertiary centers. The pooled prevalence of AS in asthma (15 studies; 2361 subjects) was 16.1% (95% confidence intervals [CI], 9.3-24.3). The prevalence of AS was significantly higher in prospective studies, studies from India, and those from developing countries. The pooled prevalence of ABPA in asthma (5 studies; 505 children) was 9.9% (95% CI, 0.81-27.6). There was significant heterogeneity and publication bias for both outcomes. Conclusions: We found a high prevalence of AS and ABPA in asthmatic children. There is a need for community-based studies from different ethnicities using a standard methodology to ascertain the true prevalence of AS and ABPA in pediatric asthma.

Understanding decision-making and educational need in the management of pediatric patients with moderate-to-severe asthma: analysis of a US-based clinician survey

BACKGROUND

Asthma creates a substantial burden on the pediatric healthcare system, particularly by those with moderate-to-severe disease. As few studies have been published specific to clinician evaluation and management of this population, this analysis serves to begin to identify educational needs and potential clinical impact.

METHODS

We conducted a case-based survey of US general pediatric (n = 227), allergy (n = 158), and pediatric pulmonology (n = 70) clinicians to understand the current approach to management of pediatric patients with moderate-to-severe asthma.

RESULTS

Results show inconsistencies in guideline adherence, identification of disease severity and control, referral practices, and knowledge of phenotypes, which may impact clinical decision making. While most clinicians refer to guidelines when managing pediatric patients with moderate-to-severe asthma, there is no preferred set, and they find the guidelines to be moderately useful. General pediatricians are more likely than specialists to have difficulty distinguishing control and severity and may not be familiar with the concept of asthma phenotype. Most surveyed pediatricians indicated they refer patients to a specialist, but did not always do so in the cases. Clinicians have little consensus on the best approach to manage patients with uncontrolled symptoms after optimized therapy. Many clinicians may have uncertainty about how elevated eosinophils or FeNO could affect patient management. Further, there may be gaps in incorporating parents and pediatric patients into shared decision-making in their care.

CONCLUSIONS

Understanding the needs of those managing patients with moderate-to-severe asthma is critical to developing effective continuing education activities to improve patient outcomes.

Biologic Therapies in Pediatric Asthma

Undeniably, childhood asthma is a multifactorial and heterogeneous chronic condition widespread in children. Its management, especially of the severe form refractory to standard therapy remains challenging. Over the past decades, the development of biologic agents and their subsequent approval has provided an advanced and very promising treatment alternative, eventually directing toward a successful precision medicine approach. The application of currently approved add-on treatments for severe asthma in children, namely omalizumab, mepolizumab, benralizumab, dupilumab, and tezepelumab have been shown to be effective in terms of asthma control and exacerbation rate. However, to date, information is still lacking regarding its long-term use. As a result, data are frequently extrapolated from adult studies. Thus, the selection of the appropriate biologic agent, the potential predictors of good asthma response, and the long-term outcome in the pediatric population are still to be further investigated. The aim of the present study was to provide an overview of the current status of the latest evidence about all licensed monoclonal antibodies (mAbs) that have emerged and been applied to the field of asthma management. The innovative future targets are also briefly discussed.

Severe asthma in children: Description of a large multidisciplinary clinical cohort

BACKGROUND

Children with severe asthma have substantial morbidity and healthcare utilization. Pediatric severe asthma is a heterogeneous disease, and a multidisciplinary approach can improve the diagnosis and management of these children.

METHODS

We reviewed the electronic health records for patients seen in the Severe Asthma Clinic (SAC) at UPMC Children's Hospital of Pittsburgh between August 2012 and October 2019.

RESULTS

Of the 110 patients in whom we extracted data, 46% were female, 48% were Black/African American, and 41% had ≥1 admission to the pediatric intensive care unit (PICU) for asthma. Compared to patients without a PICU admission, those with ≥1 PICU admission were more likely to be non-White (64.4% vs. 41.5%, p = 0.031) and more atopic (eosinophil count geometric mean = 673 vs. 319 cells/mm3 , p = 0.002; total IgE geometric mean = 754 vs. 303 KU/L, p = 0.003), and to have lower pre-bronchodilator FEV1 (58.6% [±18.1%] vs. 69.9% [±18.7%], p = 0.002) and elevated FeNO (60% vs. 22%, p = 0.02). In this cohort, 84% of patients were prescribed high-dose ICS/LABA and 36% were on biologics. Following enrollment in the SAC, severe exacerbations decreased from 3.2/year to 2.2/year (p < 0.0001); compared to the year before joining the SAC, in the following year the group had 106 fewer severe exacerbations.

CONCLUSIONS

This large cohort of children with severe asthma had a high level of morbidity and healthcare utilization. Patients with a history of PICU admissions for asthma were more likely to be nonwhite and highly atopic, and to have lower lung function. Our data support a positive impact of a multidisciplinary clinic on patients with severe childhood asthma.

Association of mold levels in urban children's homes with difficult-to-control asthma

BACKGROUND

Mold sensitization and exposure are associated with asthma severity, but the specific species that contribute to difficult-to-control (DTC) asthma are unknown.

OBJECTIVE

We sought to determine the association between overall and specific mold levels in the homes of urban children and DTC asthma.

METHODS

The Asthma Phenotypes in the Inner-City study recruited participants, aged 6 to 17 years, from 8 US cities and classified each participant as having either DTC asthma or easy-to-control (ETC) asthma on the basis of treatment step level. Dust samples had been collected in each participant's home (n = 485), and any dust remaining (n = 265 samples), after other analyses, was frozen at -20^oC. The dust samples (n = 265) were analyzed using quantitative PCR to determine the concentrations of the 36 molds in the Environmental Relative Moldiness Index. Logistic regression was performed to discriminate specific mold content of dust from homes of children with DTC versus ETC asthma.

RESULTS

Frozen-dust samples were available from 54% of homes of children with DTC (139 of 253) and ETC asthma (126 of 232). Only the average concentration of the mold Mucor was significantly (P < .001) greater in homes of children with DTC asthma. In homes with window air-conditioning units, the Mucor concentration contributed about a 22% increase (1.6 odds ratio; 95% CI, 1.2-2.2) in the ability to discriminate between cases of DTC and ETC asthma.

CONCLUSIONS

Mucor levels in the homes of urban youth were a predictor of DTC asthma, and these higher Mucor levels were more likely in homes with a window air-conditioner.

Severe asthma in children: An official statement from Saudi Pediatric Pulmonology Association

In Saudi Arabia, the prevalence of pediatric asthma ranges between 8% and 25%. However, there are no sufficient data regarding severe asthma in childhood in Saudi Arabia. Therefore, a task force has been formed by the Saudi Pediatric Pulmonology Association which is a subsidiary group of the Saudi Thoracic Society and consists of Saudi experts with well-respected academic and clinical backgrounds in the fields of pediatric asthma as well as other respiratory diseases to write a consensus on definitions, phenotypes, and pathophysiology, evaluation, and management. To achieve this, the subject was divided into various sections, each of which was assigned to at least 2 experts. Without a central literature review, the authors searched the literature using their own strategies. To reach an agreement, the entire panel reviewed and voted on proposed findings and recommendations.

Issues affecting young people with asthma through the transition period to adult care

Asthma is among the most common medical conditions affecting children and young people, with adolescence a recognised period of increased risk, overrepresented in analyses examining recent increasing asthma mortality rates. Asthma may change significantly during this period and management also occurs in the context of patients seeking increased autonomy and self-governance whilst navigating increasing academic and social demands. A number of disease factors can destabilise asthma during adolescence including: increased rates of anaphylaxis, anxiety, depression, obesity, and, in females, an emerging resistance to corticosteroids and the pro-inflammatory effects of oestrogen. Patient factors such as smoking, vaping, poor symptom recognition, treatment non-adherence and variable engagement with health services contribute to difficult to treat asthma. Significant deficiencies in the current approach to transition have been identified by a recent EAACI task force, and subsequent asthma-specific recommendations, published in 2020 provide an important framework moving forward. As with other chronic conditions, effective transition programmes plan ahead, engage with adolescents and their families to identify the patients' management priorities and the current challenges they are experiencing with treatment. Transition needs may vary significantly across asthma patients and for more complex asthma may include dedicated transition clinics involving multidisciplinary care requiring input including, amongst others, allergy and immunology, psychological medicine, respiratory physicians and scientists and nurse specialists. Across different global regions, barriers to treatment may vary but need to be elicited and an individualised approach taken to optimising asthma care which is sustainable within the local adult healthcare system.

Analysis of the Consumption of Drugs Prescribed for the Treatment of Asthma in Belgian Children

(1) Asthma is one of the most common chronic diseases in the world among children. The main purpose of this study was to analyze the consumption of asthma medications in order to investigate asthma in children (2-18 years) and the association with health care consumption; (2) a retrospective study using anonymized administrative data for 2013-2018 from the third largest Belgian health insurer was conducted; (3) in 2018, 12.9% of children received at least one asthma medication and 4.4% received at least two packages with a minimum of 30 days between purchases. Preschool children (2-6 years) were three times more likely to take asthma medication than older children (7-18 years). ICS, in combination or not with LABA, were the most dispensed drugs among children. Children with asthma medications were almost twice as likely to receive antibiotics, more likely to end up in the emergency room, and twice as likely to be hospitalized; (4) most children took ICS, according to the GINA guidelines. High rates of nebulization in young children were observed, despite the recommendation to use an inhaler with a spacing chamber as much as possible. Finally, children who took asthma medications were more likely to end up in the ER or be hospitalized.

Pediatric asthma: The REGAP consensus

Asthma is one of the main chronic diseases in childhood, due to its high prevalence and its social and health costs. This document is a summary of a consensus guideline approved by 6 Spanish pediatric societies related to asthma and endorsed by the Spanish Pediatric Association. Asthma is easily identifiable by clinical criteria in most patients. Spirometry and other tests are helpful for diagnosis, especially in atypical cases. Asthma exacerbation is a frequent manifestation of the disease and must be identified and treated promptly. When asthma symptoms are frequent and the quality of life is affected, maintenance treatment must be instituted to achieve control of the disease. Low-dose inhaled corticosteroids are effective and safe for long-term use. Education of the patient with asthma is essential for good control. The main reason for poor asthma control is non-compliance with treatment, either due to its erratic and insufficient administration, or due to poor application technique of inhaled drugs. If control is not obtained despite adequate treatment, the diagnosis must be reconsidered, as well as the factors or comorbidities that make control difficult. Other drugs can be added to avoid high doses of inhaled corticosteroids, notably montelukast or long-acting β2 adrenergic agonists. Severe or difficult-to-control asthma, which does not respond to the usual treatments, should be managed in specialized units.

Defining pediatric asthma: phenotypes to endotypes and beyond

Asthma is the most common chronic pediatric lung disease that has traditionally been defined as a syndrome of airway inflammation characterized by clinical symptoms of cough and wheeze. Highlighting the complex and heterogeneous nature of asthma, this review summarizes recent advances in asthma classification that are based on pathobiology, and thereby directly addresses limitations of existent definitions of asthma. By reviewing and contrasting clinical and mechanistic features of adult and childhood asthma, the review summarizes key biomarkers that distinguish childhood asthma subtypes. While atopy and its severity are important features of childhood asthma, there is evidence to support the existence of a childhood asthma endotype distinct from the atopic endotype. Although biomarkers of non-atopic asthma are an area of future research, we summarize a clinical approach that includes existing measures of airway-specific and systemic measures of atopy, co-existing morbidities, and disease severity and control, in the definition of childhood asthma, to empower health care providers to better characterize asthma disease burden in children. Identification of biomarkers of non-atopic asthma and the contribution of genetics and epigenetics to pediatric asthma burden remains a research need, which can potentially allow delivery of precision medicine to pediatric asthma. IMPACT: This review highlights asthma as a complex and heterogeneous disease and discusses recent advances in the understanding of the pathobiology of asthma to demonstrate the need for a more nuanced definitions of asthma. We review current knowledge of asthma phenotypes and endotypes and put forth an approach to endotyping asthma that may be useful for defining asthma for clinical care as well as for future research studies in the realm of personalized medicine for asthma.

[Pediatric asthma: The REGAP consensus]

Asthma is one of the main chronic diseases in childhood, due to its high prevalence and its social and health costs. This document is a summary of a consensus guideline approved by 6 Spanish pediatric societies related to asthma and endorsed by the Spanish Pediatric Association. Asthma is easily identifiable by clinical criteria in most patients. Spirometry and other tests are helpful for diagnosis, especially in atypical cases. Asthma exacerbation is a frequent manifestation of the disease and must be identified and treated promptly. When asthma symptoms are frequent and the quality of life is affected, maintenance treatment must be instituted to achieve control of the disease. Low-dose inhaled corticosteroids are effective and safe for long-term use. Education of the patient with asthma is essential for good control. The main reason for poor asthma control is non-compliance with treatment, either due to its erratic and insufficient administration, or due to poor application technique of inhaled drugs. If control is not obtained despite adequate treatment, the diagnosis must be reconsidered, as well as the factors or comorbidities that make control difficult. Other drugs can be added to avoid high doses of inhaled corticosteroids, notably montelukast or long-acting β2 adrenergic agonists. Severe or difficult-to-control asthma, which does not respond to the usual treatments, should be managed in specialized units.

Asthma control and psychological health in pediatric severe asthma

OBJECTIVES

Psychological comorbidities have been associated with asthma in adults and children, but have not been studied in a population of children with severe asthma. The aim of this study was to test the hypothesis that symptoms of anxiety or depression are highly prevalent in pediatric severe asthma and negatively effects asthma control.

METHODS

Longitudinal assessments of anxiety or depression symptoms (Patient Health Questionnaire-4 [PHQ-4]), asthma control (Asthma Control Test [ACT]), and lung function were performed in a single-center pediatric severe asthma clinic. Participant data were collected during routine clinical care. Primary outcomes were ACT and forced expiratory volume in 1 s per forced vital capacity (FEV1/FVC).

RESULTS

Among 43 subjects (with total 93 observations), 58.1% reported at least one anxious or depressive symptom and 18.6% had a PHQ-4 more than 2, the threshold for an abnormal test result. After adjusting for age, sex, race, and asthma medication step, there was a significant reduction in ACT for girls with PHQ-4 more than 2 (adjusted mean [SE] ACT for PHQ-4 > 2: 13.64 [0.59], ACT for PHQ-4 ≤ 2: 20.64 [1.25], p = .02) but not boys. Moreover, there was a significant differential effect of mental health impairment for girls than boys. ACT for girls with PHQ more than 2: 13.64 (0.59) compared with boys with PHQ-4 more than 2: 17.82 (0.95), adjusted mean difference ACT by sex = 4.18 points; 95% confidence interval, 0.63-7.73; p = .033. In adjusted models, there was no association between PHQ-4 more than 2 and FEV1/FVC.

CONCLUSIONS

Symptoms of anxiety and depression are common. In children with severe asthma, a PHQ-4 score more than 2 is associated with worse asthma symptom control in girls, but not boys.

Difficult and Severe Asthma in Children

Asthma is the most frequent chronic inflammatory disease of the lower airways affecting children, and it can still be considered a challenge for pediatricians. Although most asthmatic patients are symptom-free with standard treatments, a small percentage of them suffer from uncontrolled persistent asthma. In these children, a multidisciplinary systematic assessment, including comorbidities, treatment-related issues, environmental exposures, and psychosocial factors is needed. The identification of modifiable factors is important to differentiate children with difficult asthma from those with true severe therapy-resistant asthma. Early intervention on modifiable factors for children with difficult asthma allows for better control of asthma without the need for invasive investigation and further escalation of treatment. Otherwise, addressing a correct diagnosis of true severe therapy-resistant asthma avoids diagnostic and therapeutic delays, allowing patients to benefit from using new and advanced biological therapies.

Small Airway Disease in Pediatric Asthma: the Who, What, When, Where, Why, and How to Remediate. A Review and Commentary

Asthma affects all portions of the airways. Small airways, however, comprise a substantial component of the conducting lung air flow. In asthma, inflammatory processes can affect the whole respiratory tract, from central to peripheral/small airways. The emphasis in adult and pediatric respiratory disease clinics is to focus on large airway obstruction and reversibility. This information, although valuable, underemphasizes a large portion of the conduction airway of asthmatics. Standard descriptions of asthma management focus on a multiple medication approaches. We particularly focused on the management of asthma in the international guidelines for the Global Initiative for Asthma (GINA). Overall, however, minimal attention is placed on the small airway pool in asthma medical management. We took the opportunity to thoroughly review and present specific data from the adult asthma literature which supported the concept that small airway abnormalities may play a role in the pathogenesis and clinical expression of asthma. Based on the conclusions of the adult asthma literature, we here present a thorough review of the literature as it relates to small airway disease in children with asthma. We used, collectively, individual data sources of data to expand the information available from standard diagnostic techniques, especially spirometry, in the evaluation of small airway disease. As the pharmacological approaches to moderate to severe asthma are advancing rapidly into the realm of biologics, we sought to present potential pharmacological options for small airway dysfunction in pediatrics prior to biological modifier intervention.

Effects of mesenchymal stromal cell-conditioned media on measures of lung structure and function: a systematic review and meta-analysis of preclinical studies

BACKGROUND

Lung disease is a leading cause of morbidity and mortality. A breach in the lung alveolar-epithelial barrier and impairment in lung function are hallmarks of acute and chronic pulmonary illness. This review is part two of our previous work. In part 1, we demonstrated that CdM is as effective as MSCs in modulating inflammation. Herein, we investigated the effects of mesenchymal stromal cell (MSC)-conditioned media (CdM) on (i) lung architecture/function in animal models mimicking human lung disease, and (ii) performed a head-to-head comparison of CdM to MSCs.

METHODS

Adhering to the animal Systematic Review Centre for Laboratory animal Experimentation protocol, we conducted a search of English articles in five medical databases. Two independent investigators collected information regarding lung: alveolarization, vasculogenesis, permeability, histologic injury, compliance, and measures of right ventricular hypertrophy and right pulmonary pressure. Meta-analysis was performed to generate random effect size using standardized mean difference with 95% confidence interval.

RESULTS

A total of 29 studies met inclusion. Lung diseases included bronchopulmonary dysplasia, asthma, pulmonary hypertension, acute respiratory distress syndrome, chronic obstructive pulmonary disease, and pulmonary fibrosis. CdM improved all measures of lung structure and function. Moreover, no statistical difference was observed in any of the lung measures between MSCs and CdM.

CONCLUSIONS

In this meta-analysis of animal models recapitulating human lung disease, CdM improved lung structure and function and had an effect size comparable to MSCs.

Monoclonal Antibody Therapy in Childhood Asthma

PURPOSE OF REVIEW

There has been an explosion of monoclonal antibodies in the treatment of severe uncontrolled adult asthma. Studies have now been published in severe pediatric asthma. There are numerous questions that need to be answered in determining whether these modalities are appropriate and safe in children.

RECENT FINDINGS

This is a narrative review examining the latest pediatric literature on monoclonal antibodies, both approved and in the pipeline, for uncontrolled asthma. Presently, all of the biologics are positioned to treat patients with underlying type 2 high disease. Two monoclonal antibodies are approved for children 6 years of age and older, omalizumab and mepolizumab, with more likely approved in the near future. The effect of these agents in controlling severe pediatric asthma is promising. Data is limited to long-term efficacy and safety, and whether any agent has an effect on the natural history of asthma.

Severe Asthma in Childhood

Severe asthma is broadly defined as asthma requiring a high level of therapy, usually high doses of inhaled corticosteroids, to bring under control. Children who remain symptomatic despite such treatment are a heterogeneous population, and bear a high burden of disease and require high resource utilization. Children with severe asthma require a comprehensive evaluation, careful consideration of alternative diagnoses and comorbid conditions, assessment of medication adherence and environmental conditions, and frequent disease monitoring.

Adjuvant treatment with Xiaoqinglong formula for bronchial asthma: Protocol of systematic review and meta-analysis

BACKGROUND

Bronchial asthma is one of the most common chronic diseases in the world and has become a serious public health problem. Combination therapy has become the first choice for clinical treatment of bronchial asthma. In addition to the combined use of routine medication, traditional Chinese medicine as an adjuvant therapy is also considered. Xiaoqinglong Decoction (XQLD) is an effective prescription of traditional Chinese medicine in treating asthma, and there are more and more clinical reports about its combination with western medicine in treating asthma. Therefore, we designed this study protocol to evaluate the adjuvant role of XQLD in the treatment of bronchial asthma.

METHOD

The following electronic databases will be systematically searched from inception to April 2019: PubMed, EMBASE database, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wan Fang, Chinese Scientific Journals Database (VIP), and China Biology Medicine disc, (CBM). And the following primary outcomes will be tested, including effective rate (ER), pulmonary function (FEV1, PEF, FEV1/FVC), adverse reactions (AR). RevMan5 software will be used for literature quality evaluation and stata14.0 software will be used for data synthesis and analysis.

RESULT

To evaluate the efficacy and safety of Xiaoqinglong decoction in combination therapy by observing the outcomes of efficacy, adverse reactions and pulmonary function.

CONCLUSION

This study protocol will be used to evaluate the efficacy and safety of XQLD in combination with conventional drugs in the treatment of bronchial asthma, as well as the adjuvant role of XQLD in combination.

PROSPERO REGISTRATION NUMBER

CRD42019133549.

Asthma in Children and Adults-What Are the Differences and What Can They Tell us About Asthma?

Asthma varies considerably across the life course. Childhood asthma is known for its overall high prevalence with a male predominance prior to puberty, common remission, and rare mortality. Adult asthma is known for its female predominance, uncommon remission, and unusual mortality. Both childhood and adult asthma have variable presentations, which are described herein. Childhood asthma severity is associated with duration of asthma symptoms, medication use, lung function, low socioeconomic status, racial/ethnic minorities, and a neutrophilic phenotype. Adult asthma severity is associated with increased IgE, elevated FeNO, eosinophilia, obesity, smoking, and low socioeconomic status. Adult onset disease is associated with more respiratory symptoms and asthma medication use despite higher prebronchodilator FEV1/FVC. There is less quiescent disease in adult onset asthma and it appears to be less stable than childhood-onset disease with more relapses and less remissions.

Severe asthma in children: Evaluation and management

Severe asthma in children is associated with significant morbidity. Children with severe asthma are at increased risk for adverse outcomes including medication-related side effects, life-threatening exacerbations, and impaired quality of life. It is important to differentiate between severe therapy resistant asthma and difficult-to-treat asthma due to comorbidities. The most common problems that need to be excluded before a diagnosis of severe asthma can be made are poor medication adherence, poor medication technique or incorrect diagnosis of asthma. Difficult to treat asthma is a much more common reason for persistent symptoms and exacerbations and can be managed if comorbidities are clearly addressed. Children with persistent symptoms and exacerbations despite correct inhaler technique and good medical adherence to standard Step 4 asthma therapies according to the guidelines^1,2, should be referred to an asthma specialist with expertise in severe asthma.

Asthma in Children: A Brief Review for Primary Care Providers

Pediatric asthma is a common chronic condition with wide-ranging implications for children's health, their families, and the health care system. The diagnosis may be relatively straightforward for the child with characteristic symptoms, triggers, and response to therapy, but there are other less common presentations that can make the diagnosis challenging. Diagnosing asthma in a toddler with recurrent wheezing can be particularly difficult. Treating asthma in a step-wise fashion usually reduces symptom frequency and improves asthma control. Asthma exacerbations and poor outcomes from acute exacerbations remain an area in which we have room for improvement. This article provides an overview of the diagnosis and management of childhood asthma for the primary care provider. [Pediatr Ann. 2019;48(3):e103-e109.].

Expression of corticosteroid-regulated genes by PBMCs in children with asthma

BACKGROUND

Variability in response to inhaled corticosteroids (ICSs) can result in less than optimal asthma control. Development of biomarkers assessing the therapeutic efficacy of corticosteroids is important.

OBJECTIVE

We sought to examine whether in vitro PBMC responses to corticosteroids relate to the clinical ICS response.

METHODS

PBMCs were collected from 125 children with asthma (6-17 years) at enrollment (visit 0 [V0]) and after 1 year of bimonthly guidelines-based management visits (visit 6 [V6]). Difficult-to-control and easy-to-control asthma were defined as requiring daily therapy with 500 μg or more of fluticasone propionate (FLU) with or without a long-acting β-agonist versus 100 μg or less of FLU in at least 4 visits. mRNA levels of glucocorticoid receptor α and corticosteroid transactivation (FK506-binding protein 5) and transrepression markers (IL-8 and TNF-α) were measured by using RT-PCR in freshly isolated cells and in response to 10-8 mol/L FLU.

RESULTS

Compared with PBMCs from patients with easy-to-control asthma, PBMCs from those with difficult-to-control asthma had significantly lower glucocorticoid receptor α levels at V0 (P = .05). A 30% increase in IL-8 suppression by FLU (P = .04) and a trend for increased TNF-α suppression by FLU between V0 and V6 (P = .07) were observed in patients with easy-to-control asthma. In contrast, no changes between V0 and V6 in IL-8 and TNF-α suppression by FLU were observed in patients with difficult-to-control asthma. Corticosteroid-mediated transactivation (FK506-binding protein 5 induction by FLU) increased in the PBMCs of patients with difficult-to-control and easy-to-control asthma between V0 and V6 (P = .05 and P = .03, respectively).

CONCLUSIONS

PBMCs of children with difficult-to-control asthma treated with guidelines-based therapy and requiring high-dose ICSs had reduced in vitro responsiveness to corticosteroids.

Current State and Future of Biologic Therapies in the Treatment of Asthma in Children

There is increasing recognition of phenotypic variability in pediatric asthma, providing the opportunity for a more personalized approach to therapy. Increasingly biologic therapies, in particular those targeting the "allergic" (or T helper 2) pathway, are being considered for children with severe asthma. However, there is a great deal of variability in the extent these biologic therapies have been studied in children, as well as efficacy of results thus far. The goal of this article is to review the mechanism of action, efficacy, and potential predictive and monitoring biomarkers of the biologic medications focusing on the pediatric population, in an effort to establish a more personalized approach to asthma in the pediatric population for the 21st century.

New Drugs for Pediatric Asthma

Asthma is the most common chronic disease in children. As suggested by international guidelines, the main goals of asthma treatment are symptoms control and lung function preservation, through a stepwise and control-based approach. The first line therapy based on inhaled corticosteroids may fail to reach control in more than one third of patients, especially adolescents, and in these lung function and quality of life may progressively worsen. Treatment with omalizumab, the first anti-immunoglobulin E recombinant humanized monoclonal antibody, has been definitely approved in pediatric uncontrolled asthma. In this review, we discuss the mechanisms and potential roles of emerging therapies for pediatric severe asthma. Novel biologic drugs (i.e., dupilumab, mepolizumab, reslizumab, and benralizumab) seem to be promising in reducing annual exacerbation rates and steroid-use in glucocorticoid-dependent cases, but available data are few and limited to adolescents and adults. Evidences on the use of the muscarinic antagonist tiotropium as controller medication in pediatric settings are progressively growing, sustaining an application as asthma maintenance treatment in children aged >6 years and in preschool children with persistent asthmatic symptoms, but well powered trials are needed to confirm its safety and efficacy. New inhaled corticosteroids (i.e., ciclesonide and mometasone) are effective as once-daily controller therapy, but long-term studies in the different pediatric ages are needed to compare effectiveness and safety to usual treatments. At present, the role of macrolides in pediatric severe asthma is controversial and their administration is not recommended routinely, but may be considered in children with neutrophilic asthma for reducing daily oral steroids administration and improving lung function. Despite the availability of several novel therapeutic strategies for uncontrolled asthma, future trials targeted at specific pediatric age subgroups are needed to support evidences of safety and efficacy also in children.

Measuring Airway Obstruction in Severe Asthma in Children

Lung function is an important tool in the diagnosis and monitoring of patients with asthma at all ages. Airway obstruction is a typical feature of asthma and it can be assessed with several lung function techniques. Spirometry, respiratory resistance and reactance, and lung volumes are available to measure it at different ages and in children. The assessment of a bronchodilator response is always recommended to show the reversibility of the obstruction. Poor lung function is a predictor of poor asthma outcome and a low Forced Expiratory Volume in the first second of expiration percent predicted measured with spirometry, has been shown to be associated with a higher risk of having an exacerbation during the following year independently of the presence of asthma symptoms. In severe asthma lung function assessment is used to distinguish different phenotypes, children with severe asthma have worse airflow limitation prior to administration of a bronchodilator than children with non severe asthma. Airway resistance and reactance are indirect measurements of airway obstruction and they can be measured with the forced oscillation technique, which is feasible also in non-collaborative children. This technique can be more informative in discriminating patients with asthma from healthy controls and is able to indicate a more peripheral involvement of the airways. The role of this technique in severe asthma is still debated. In conclusion lung function is useful in the clinical management of children with severe asthma.