Anti-Siglec-8 Antibody for Eosinophilic Gastritis and Duodenitis.

BACKGROUND: Eosinophilic gastritis and duodenitis are characterized by gastrointestinal mucosal eosinophilia, chronic symptoms, impaired quality of life, and a lack of adequate treatments. Mast-cell activity may contribute to the pathogenesis of the conditions. AK002 (lirentelimab) is an anti-Siglec-8 antibody that depletes eosinophils and inhibits mast cells and that has shown potential in animal models as a treatment for eosinophilic gastritis and duodenitis. METHODS: In this phase 2 trial, we randomly assigned adults who had symptomatic eosinophilic gastritis, eosinophilic duodenitis, or both conditions in a 1:1:1 ratio to receive four monthly infusions of low-dose AK002, high-dose AK002, or placebo. The primary end point was the change in gastrointestinal eosinophil count from baseline to 2 weeks after the final dose; to maximize statistical power, we evaluated this end point in the placebo group as compared with the combined AK002 group. Secondary end points were treatment response (>30% reduction in total symptom score and >75% reduction in gastrointestinal eosinophil count) and the change in total symptom score. RESULTS: Of the 65 patients who underwent randomization, 43 were assigned to receive AK002 and 22 were assigned to receive placebo. The mean percentage change in gastrointestinal eosinophil count was -86% in the combined AK002 group, as compared with 9% in the placebo group (least-squares mean difference, -98 percentage points; 95% confidence interval [CI], -121 to -76; P<0.001). Treatment response occurred in 63% of the patients who received AK002 and in 5% of the patients who received placebo (difference, 58 percentage points; 95% CI, 36 to 74; P<0.001). The mean change in total symptom score was -48% with AK002 and -22% with placebo (least-squares mean difference, -26 percentage points; 95% CI, -44 to -9; P = 0.004). Adverse events associated with AK002 were similar to those with placebo, with the exception of higher percentages of patients having mild-to-moderate infusion-related reactions with AK002 (60% in the combined AK002 group and 23% in the placebo group). CONCLUSIONS: In patients with eosinophilic gastritis or duodenitis, AK002 reduced gastrointestinal eosinophils and symptoms. Infusion-related reactions were more common with AK002 than with placebo. (Funded by Allakos; ENIGMA ClinicalTrials.gov number, NCT03496571.).

Dupilumab leads to better-controlled asthma and quality of life in children: the VOYAGE study.

BACKGROUND: Dupilumab has shown long-term treatment benefits in children with uncontrolled asthma. We assessed in more detail the impact of dupilumab on asthma control and health-related quality of life (HRQoL) in children and their caregivers. METHODS: Children aged 6-11 years with uncontrolled moderate-to-severe type 2 asthma (baseline blood eosinophils ≥150 cells·µL-1 or fractional exhaled nitric oxide ≥20 ppb; n=350) were treated with dupilumab or placebo for 52 weeks in the VOYAGE study. Primary outcomes of these analyses were asthma control (change from baseline in Asthma Control Questionnaire 7 Interviewer-Administered (ACQ-7-IA) and achieving a clinically meaningful response of ≥0.5 points); proportion of patients achieving well-controlled asthma or better (ACQ-7-IA ≤0.75 points); effect on patients' (Standardised Paediatric Asthma Quality of Life Questionnaire Interviewer-Administered (PAQLQ(S)-IA)) and caregivers' (Paediatric Asthma Caregiver's Quality of Life Questionnaire (PACQLQ)) HRQoL; and allergic rhinitis-related QoL. RESULTS: Dupilumab versus placebo significantly improved children's ACQ-7-IA scores by week 4 with sustained improvements through week 52 (least squares mean difference at week 52: -0.44, 95% CI -0.59- -0.30; p<0.0001); a higher proportion achieved a clinically meaningful response (week 52: 86% versus 75%; p=0.0051). At weeks 24 and 52, more children who received dupilumab achieved well-controlled asthma (ACQ-7-IA ≤0.75 points: 61% versus 43%; p=0.0001 and 70% versus 46%; p<0.0001, respectively). Significant improvements in PAQLQ(S)-IA and PACQLQ scores were observed by week 52. CONCLUSIONS: In children aged 6-11 years with moderate-to-severe type 2 asthma, dupilumab treatment was associated with rapid, sustained improvements in asthma control. HRQoL was significantly improved for children and their caregivers.

Effect of vitamin D supplementation on total and allergen-specific IgE in children with asthma and low vitamin D levels.

BACKGROUND: Observational studies have yielded inconsistent findings for the relation between vitamin D level and total IgE or allergic sensitization. OBJECTIVE: To determine whether vitamin D supplementation reduces levels of total IgE and IgE to each of 2 common indoor allergens in children with asthma and low vitamin D levels. METHODS: Total IgE, IgE to Dermatophagoides pteronyssinus, and IgE to Blattella germanica were measured at the randomization and exit visits for 174 participants in the Vitamin D Kids Asthma Study, a multicenter, double-blind, randomized placebo-controlled trial of vitamin D3 supplementation (4000 IU/d) to prevent severe exacerbations in children with persistent asthma and vitamin D levels less than 30 ng/mL. Multivariable linear regression was used for the analysis of the effect of vitamin D supplementation on change in each IgE measure. RESULTS: Participants were followed for an average of 316 days. At the exit visit, more subjects in the vitamin D arm achieved a vitamin D level equal to or more than 30 ng/mL compared with those in the placebo arm (87% vs 30%; P < .001). In a multivariable analysis, vitamin D3 supplementation had no significant effect on change in total IgE, IgE to Dermatophagoides pteronyssinus, or IgE to Blattella germanica between the exit and randomization visits (eg, for log10 total IgE, ß = 0.007; 95% CI, -0.061 to 0.074; P = .85). CONCLUSIONS: Vitamin D supplementation, compared with placebo, has no significant effect on serum levels of total IgE, IgE to dust mite, or IgE to cockroach in children with asthma and low vitamin D levels.

Violence-related distress and lung function in two longitudinal studies of youth.

BACKGROUND: Exposure to violence has been associated with lower lung function in cross-sectional studies. METHODS: We examined whether increasing violence-related distress over time is associated with worse lung function and worse asthma control or quality of life in a secondary analysis of a 48-week randomised clinical trial in 98 youth with asthma (aged 9-16 years) treated with low-dose inhaled corticosteroids (Vitamin D Kids Asthma Study (VDKA)). We then replicated our findings for lung function in a prospective study of 232 Puerto Rican youth followed for an average of 5.4 years. Violence-related distress was assessed using the Checklist of Children's Distress Symptoms (CCDS) scale. Our outcomes of interest were percent predicted lung function measures and (in VDKA only) asthma control (assessed using the Asthma Control Test) and asthma-related quality of life (assessed using the Pediatric Asthma Quality of Life Questionnaire (PAQLQ)). RESULTS: In a multivariable analysis in VDKA, each 1-point increment in CCDS score was associated with decrements of 3.27% in forced expiratory volume in 1 s (FEV1) % pred (95% CI -6.44- -0.22%; p=0.04), 2.65% in forced vital capacity (FVC) % pred (95% CI -4.86- -0.45%; p=0.02) and 0.30 points in the overall PAQLQ score (95% CI -0.50- -0.10 points; p<0.01). Similar findings for FEV1 and FVC were obtained in the prospective study of Puerto Rican youth. CONCLUSIONS: Our findings suggest that violence-related distress may worsen lung function and quality of life in youth with asthma (even those treated with low-dose inhaled corticosteroids), and further support policies to reduce exposure to violence among children in the USA and Puerto Rico.

Treatment by biomarker-informed endotype vs guideline care in children with difficult-to-treat asthma.

BACKGROUND: Asthma is heterogeneous, contributing to difficulty in disease management. OBJECTIVE: To develop a biomarker-informed treatment model for difficult-to-treat (DTT) asthma and conduct a pilot feasibility study. METHODS: School-aged children (n = 21) with DTT asthma were enrolled and completed 3 medical visits (V1-V3). V2 and V3 were completed approximately 3.5 months and 12 months after V1, respectively. At V1, guideline care and adherence interventions were initiated, and blood samples were collected for asthma biomarker assessment. A personalized treatment algorithm was developed based on biomarkers (treatment by endotype) and was implemented at V2. Asthma outcomes were compared from V1 to V2 (guideline-based care) to V2 to V3 (guideline + biomarker-informed care). RESULTS: Overall retention was 86%. There was an even distribution of participants with allergy, without allergy, and with mixed allergies. The participants received an average of 5.9 interventions (range, 3-9). The allergic phenotype was characterized by increased CDHR3 risk genotype and high transepidermal water loss. High serum interleukin-6 level was most notable in the mixed allergic subgroup. The nonallergic phenotype was characterized by vitamin D deficiency and poor steroid treatment responsiveness. The personalized treatment plans were associated with decreased emergency department visits (median, 1 vs 0; P = .04) and increased asthma control test scores (median, 22.5 vs 23.0; P = .01). CONCLUSION: The biomarker-based treatment algorithm triggered interventions on top of guideline care in all children with DTT asthma studied, supporting the need for this type of multipronged approach. Our findings identify the minimal biomarker set that is informative, reveal that this treatment-by-endotype intervention is feasible and may be superior to guideline care alone, and provide a strong foundation for a definitive trial. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04179461.

Effect of Vitamin D3 Supplementation on Severe Asthma Exacerbations in Children With Asthma and Low Vitamin D Levels: The VDKA Randomized Clinical Trial.

Importance: Severe asthma exacerbations cause significant morbidity and costs. Whether vitamin D3 supplementation reduces severe childhood asthma exacerbations is unclear. Objective: To determine whether vitamin D3 supplementation improves the time to a severe exacerbation in children with asthma and low vitamin D levels. Design, Setting, and Participants: The Vitamin D to Prevent Severe Asthma Exacerbations (VDKA) Study was a randomized, double-blind, placebo-controlled clinical trial of vitamin D3 supplementation to improve the time to severe exacerbations in high-risk children with asthma aged 6 to 16 years taking low-dose inhaled corticosteroids and with serum 25-hydroxyvitamin D levels less than 30 ng/mL. Participants were recruited from 7 US centers. Enrollment started in February 2016, with a goal of 400 participants; the trial was terminated early (March 2019) due to futility, and follow-up ended in September 2019. Interventions: Participants were randomized to vitamin D3, 4000 IU/d (n = 96), or placebo (n = 96) for 48 weeks and maintained with fluticasone propionate, 176 µg/d (6-11 years old), or 220 µg/d (12-16 years old). Main Outcomes and Measures: The primary outcome was the time to a severe asthma exacerbation. Secondary outcomes included the time to a viral-induced severe exacerbation, the proportion of participants in whom the dose of inhaled corticosteroid was reduced halfway through the trial, and the cumulative fluticasone dose during the trial. Results: Among 192 randomized participants (mean age, 9.8 years; 77 girls [40%]), 180 (93.8%) completed the trial. A total of 36 participants (37.5%) in the vitamin D3 group and 33 (34.4%) in the placebo group had 1 or more severe exacerbations. Compared with placebo, vitamin D3 supplementation did not significantly improve the time to a severe exacerbation: the mean time to exacerbation was 240 days in the vitamin D3 group vs 253 days in the placebo group (mean group difference, -13.1 days [95% CI, -42.6 to 16.4]; adjusted hazard ratio, 1.13 [95% CI, 0.69 to 1.85]; P = .63). Vitamin D3 supplementation, compared with placebo, likewise did not significantly improve the time to a viral-induced severe exacerbation, the proportion of participants whose dose of inhaled corticosteroid was reduced, or the cumulative fluticasone dose during the trial. Serious adverse events were similar in both groups (vitamin D3 group, n = 11; placebo group, n = 9). Conclusions and Relevance: Among children with persistent asthma and low vitamin D levels, vitamin D3 supplementation, compared with placebo, did not significantly improve the time to a severe asthma exacerbation. The findings do not support the use of vitamin D3 supplementation to prevent severe asthma exacerbations in this group of patients. Trial Registration: ClinicalTrials.gov Identifier: NCT02687815.

Effect of exogenous interferons on rhinovirus replication and airway inflammatory responses.

BACKGROUND: Human rhinoviruses (HRVs) are the most common cause of asthma exacerbations. In airway epithelial cells, the primary site of HRV infection, decreased production of interferons (IFNs) may result in greater susceptibility to HRV and worsened symptoms. Thus, exogenous IFN could supplement the innate immune response and provide a treatment for virus-induced asthma exacerbations. Furthermore, the effects of exogenous IFN could be type specific in part because of the cellular distribution of type 1 and type 2 IFN receptors. OBJECTIVE: To investigate the effects of exogenous IFNs on HRV replication in bronchial epithelial cells. METHODS: Frozen stocks of primary human bronchial epithelial cells from healthy donors were cultured in monolayers; pretreated (24 hours) with 0.1-ng/mL, 1-ng/mL, or 10-ng/mL doses of IFN-α, -ß, -λ1, or -λ2; and infected with HRV-1A. Viral replication was quantified using real-time reverse transcription-polymerase chain reaction, and cytokine and chemokine secretion 24 hours after infection was measured by multiplex enzyme-linked immunosorbent assay. RESULTS: Compared with untreated samples, IFN-α, IFN-ß, IFN-λ1, and IFN-λ2 (0.1 ng/mL) significantly reduced HRV replication after high- (P < .02) and low-dose inoculation (P < .05). Similar effects were seen in 1-ng/mL and 10-ng/mL doses of IFN, where HRV replication was significantly decreased in both high- (P < .001) and low-dose inoculation (P < .001). Treatment with IFNs also enhanced HRV-induced IFN-γ-induced protein 10 secretion (P < .001). Finally, treatment with either IFN-λ1 or IFN-λ2 significantly increased HRV-induced secretion of RANTES (regulated on activation, normal T-expressed, and presumably secreted) (P < .05) but not IL-1ß or vascular endothelial growth factor. CONCLUSION: These findings suggest that exogenous IFNs, IFN-λ1 in particular, warrant further study as a potential therapy for virus-induced asthma exacerbations.

Innate immune responses to rhinovirus are reduced by the high-affinity IgE receptor in allergic asthmatic children.

BACKGROUND: Children with allergic asthma have more frequent and severe human rhinovirus (HRV)-induced wheezing and asthma exacerbations through unclear mechanisms. OBJECTIVE: We sought to determine whether increased high-affinity IgE receptor (FcεRI) expression and cross-linking impairs innate immune responses to HRV, particularly in allergic asthmatic children. METHODS: PBMCs were obtained from 44 children, and surface expression of FcεRI on plasmacytoid dendritic cells (pDCs), myeloid dendritic cells, monocytes, and basophils was assessed by using flow cytometry. Cells were also incubated with rabbit anti-human IgE to cross-link FcεRI, followed by stimulation with HRV-16, and IFN-α and IFN-λ1 production was measured by Luminex. The relationships among FcεRI expression and cross-linking, HRV-induced IFN-α and IFN-λ1 production, and childhood allergy and asthma were subsequently analyzed. RESULTS: FcεRIα expression on pDCs was inversely associated with HRV-induced IFN-α and IFN-λ1 production. Cross-linking FcεRI before HRV stimulation further reduced PBMC IFN-α (47% relative reduction; 95% CI, 32% to 62%; P< .0001) and IFN-λ1 (81% relative reduction; 95% CI, 69% to 93%; P< .0001) secretion. Allergic asthmatic children had higher surface expression of FcεRIα on pDCs and myeloid dendritic cells when compared with that seen in nonallergic nonasthmatic children. Furthermore, after FcεRI cross-linking, allergic asthmatic children had significantly lower HRV-induced IFN responses than allergic nonasthmatic children (IFN-α, P= .004; IFN-λ1, P= .02) and nonallergic nonasthmatic children (IFN-α, P= .002; IFN-λ1, P= .01). CONCLUSIONS: Allergic asthmatic children have impaired innate immune responses to HRV that correlate with increased FcεRI expression on pDCs and are reduced by FcεRI cross-linking. These effects likely increase susceptibility to HRV-induced wheezing and asthma exacerbations.

An International, Retrospective Study of Off-Label Biologic Use in the Treatment of Hypereosinophilic Syndromes.

BACKGROUND: Treatment of hypereosinophilic syndrome (HES) often requires the use of immunomodulators with substantial side effect profiles. The emergence of biologics offers an alternative treatment modality. OBJECTIVE: To examine real-world practice data to describe the safety and consequences of various biologics suspected to directly or indirectly affect eosinophilic inflammation for the treatment of HES. METHODS: Retrospective data from 13 centers were collected via an online Research Electronic Data Capture repository. Inclusion criteria included (1) peripheral eosinophil count of 1,500/mm3 or greater without a secondary cause; (2) clinical manifestations attributable to the eosinophilia; and (3) having received mepolizumab (anti-IL-5), benralizumab (afucosylated anti-IL-5 receptor α), omalizumab (anti-IgE), alemtuzumab (anti-CD52), dupilumab (anti-IL-4 receptor α), or reslizumab (anti-IL-5) outside a placebo-controlled clinical trial. RESULTS: Of the 151 courses of biologics prescribed for 121 patients with HES, 59% resulted in improved HES symptoms and 77% enabled tapering of other HES medications. Overall, 105 patients were receiving daily systemic glucocorticoids at the time of a biologic initiation and were able to reduce the glucocorticoid dose by a median reduction of 10 mg of daily prednisone equivalents. Biologics were generally safe and well-tolerated other than infusion reactions with alemtuzumab. Thirteen of 24 patients had clinical improvement after switching biologics and nine patients responded to increasing the dose of mepolizumab after a lack of response to a lower dose. CONCLUSIONS: Biologics may offer a safer treatment alternative to existing therapies for HES, although the optimal dosing and choice for each subtype of HES remain to be determined. Limitations of this study include its retrospective nature and intersite differences in data collection and availability of each biologic.

Evaluation of Risk Scores to Predict Pediatric Severe Asthma Exacerbations.

BACKGROUND: Asthma exacerbations commonly lead to unplanned health care utilization and are costly. Early identification of children at increased risk of asthma exacerbations would allow a proactive management approach. OBJECTIVE: We evaluated common asthma risk factors to predict the probability of exacerbation for individual children aged 0-21 years using data from the electronic medical record (EMR). METHODS: We analyzed longitudinal EMR data for over 3000 participants with asthma seen at Cincinnati Children's Hospital Medical Center over a 7-year period. The study population was divided into 3 age groups: 0-4, 5-11, and 12-21 years. Each age group was divided into a derivation cohort and a validation cohort, which were used to build a risk score model. We predicted risk of exacerbation in the next 12 months, validated the scores by risk stratum, and developed a clinical tool to determine the risk level based on this model. RESULTS: Risk model results were confirmed with validation cohorts by calendar year and age groups. Race, allergic sensitization, and smoke exposure were each important risk factors in the 0-4 age group. Abnormal spirometry and obesity were more sensitive predictors of exacerbation in children >12 years. For each age group, a higher expanded score was associated with a higher predicted probability of an asthma exacerbation in the subsequent year. CONCLUSION: This asthma exacerbation prediction model, and the associated clinical tool, may assist clinicians in identifying children at high risk for exacerbation that may benefit from more aggressive management and targeted risk mitigation.

Preventing asthma in high risk kids (PARK) with omalizumab: Design, rationale, methods, lessons learned and adaptation.

Asthma remains one of the most important challenges to pediatric public health in the US. A large majority of children with persistent and chronic asthma demonstrate aeroallergen sensitization, which remains a pivotal risk factor associated with the development of persistent, progressive asthma throughout life. In individuals with a tendency toward Type 2 inflammation, sensitization and exposure to high concentrations of offending allergens is associated with increased risk for development of, and impairment from, asthma. The cascade of biological responses to allergens is primarily mediated through IgE antibodies and their production is further stimulated by IgE responses to antigen exposure. In addition, circulating IgE impairs innate anti-viral immune responses. The latter effect could magnify the effects of another early life exposure associated with increased risk of the development of asthma - viral infections. Omalizumab binds to circulating IgE and thus ablates antigen signaling through IgE-related mechanisms. Further, it has been shown restore IFN-α response to rhinovirus and to reduce asthma exacerbations during the viral season. We therefore hypothesized that early blockade of IgE and IgE mediated responses with omalizumab would prevent the development and reduce the severity of asthma in those at high risk for developing asthma. Herein, we describe a double-blind, placebo-controlled trial of omalizumab in 2-3 year old children at high risk for development of asthma to prevent the development and reduce the severity of asthma. We describe the rationale, methods, and lessons learned in implementing this potentially transformative trial aimed at prevention of asthma.

Non-IgE-mediated food allergy during infancy.

PURPOSE OF REVIEW: Is to highlight the recent advances in the diagnosis and management of non-IgE-mediated food allergy which is a common consideration in primary care and in allergy and gastroenterology subspecialty practices evaluating infants. RECENT FINDINGS: The review focuses on food protein-induced enterocolitis syndrome (FPIES) and includes other non-IgE-mediated food allergy in nursing infants, food protein-induced allergic proctocolitis, and food protein-induced enteropathy. For FPIES, we review the 2017 International Consensus Guidelines that provided the first comprehensive framework for its diagnosis and management and that were supplemented by a 2019 position paper by the European Academy of Allergy and Clinical Immunology. We review recent reports that support FPIES as a diagnosis of primarily infants, highlight the problem of delayed diagnosis, reveal the need for improved biomarkers, emphasize new and common food protein triggers, and identify new approaches for evaluation of tolerance. SUMMARY: As formal diagnostic criteria for non-IgE-mediated food allergies are defined and prevalence data is increasingly reported, there will likely be improved recognition and evaluation of these conditions. Currently, large-scale prospective studies evaluating their incidence and prevalence, associated risk factors, and natural history are needed. Although avoidance of the suspected trigger food protein remains the cornerstone of management, additional studies of underlying pathophysiology and biomarkers of disease will likely reveal new avenues for therapeutics.

Eosinophilic Esophagitis: an Important Comorbid Condition of Asthma?

Eosinophilic esophagitis and asthma are frequently found as comorbid conditions in children and adults along with other manifestations of atopic diathesis. These two conditions have similar T helper 2 responses-driven pathophysiology and share common management strategies such as using systemic corticosteroids and targeted anti-cytokine biologic therapies. Review of the literature finds that asthma is often a comorbid condition in eosinophilic esophagitis in both children and adults; however, the EoE-asthma relationship remains poorly characterized mechanistically and clinically. EoE and asthma commonly share several comorbid conditions such as allergic rhinitis and gastroesophageal reflux disease; therefore, addressing these comorbid conditions has the potential to improve and/or maintain control in both diseases. Similar to asthma, patients with EoE frequently demonstrate elevations in serum markers of atopy, including serum IgE levels, peripheral eosinophil counts, and T helper 2-related cytokines. Gastroesophageal reflux disease is thought to affect asthma through microaspirations, airway hyperresponsiveness, and increased vagal tone. The understanding of the relationship between gastroesophageal reflux and EoE is still evolving but seems to be bidirectional and interactive. In terms of treatment, similar classes of medications have been used in both EoE and asthma. In both children and adults, EoE remission can be achieved by food trigger avoidance and use of corticosteroids and biologic therapies. Asthma control is mostly achieved through inhaled corticosteroids, and long but biologic therapies are increasingly used in severe subsets of the disease. Significant clinical and mechanistic work needs to be accomplished to better understand the relationship between asthma, EoE, and their interaction with other allergic diseases. Understanding whether shared mechanisms exist can lead to the development of new diagnostic and therapeutic strategies. The following review examines the existing literature regarding prevalence, common comorbidities, and potential therapeutic approach and identifies gaps in knowledge and future directions.

Recent advances in eosinophilic esophagitis.

Eosinophilic esophagitis is a chronic, antigen-driven, eosinophil-predominant inflammatory disease of the esophagus and affects both children and adults. Cutting-edge technologies, such as genome-wide association studies, have advanced our understanding of the disease pathogenesis at a remarkable rate. Recent insights from genetic and mechanistic studies have concluded that a complex interplay between genetic and environmental risk factors, allergic sensitization, and esophageal-specific pathways leads to disease pathogenesis. Importantly, recent epidemiologic studies have found that the incidence and prevalence of eosinophilic esophagitis continue to rise. New guidelines have advocated the elimination of the term proton pump inhibitor (PPI)-responsive esophageal eosinophilia and have recommended using PPIs as a first-line treatment modality. Systemic reviews and meta-analyses confirm the efficacy of PPIs, topical corticosteroids, and empiric food elimination diets. Unmet needs include the development of birth cohort studies, validated diagnostic scoring systems, minimally invasive disease-monitoring methods, and the development of new therapies.

Should a Preschool Child with Acute Episodic Wheeze be Treated with Oral Corticosteroids? A Pro/Con Debate.

Traditionally, preschool-aged children with an acute wheezing episode have been treated with oral corticosteroids (OCSs) based on the efficacy of OCSs in older children and adolescents. However, this practice has been recently challenged based on the results of recent studies. The argument supporting the use of OCSs underscores the observation that many children with recurrent preschool wheezing develop atopic disease in early life which predicts both an increased risk to develop asthma in later life and response to OCS therapy. Further, review of the literature demonstrates heterogeneity of study designs, OCS dosage, interventions, study medication adherence, and settings and overall lack of predefined preschool wheezing phenotypes. The heterogeneity of these studies does not allow a definitive recommendation discouraging OCS use. Advocates against the use of OCSs in this population argue that most of studies investigating the efficacy of OCSs in acute episodic wheeze in preschool-aged children have not demonstrated beneficial effects. Moreover, repeated OCS bursts may be associated with adverse effects. Finally, both sides can agree that there is a significant need to conduct efficacy trials evaluating OCS treatment in preschool-aged children with recurrent wheezing targeted at phenotypes that would be expected to respond to OCSs. This article presents a summary of recent literature regarding the use of OCSs for acute episodic wheezing in preschool-aged children and a "pro" and "con" debate for such use.

Management of asthma in school-aged children and adolescents.

Asthma is one of the most common childhood diseases in the world and a significant cause of morbidity and health care expenditures. United States and international evidence-based guidelines created and updated in the past 2 decades have significantly improved the consistency and effectiveness of asthma care in children. Assessing severity and monitoring control using the impairment and risk domains is fundamental to effective management. At every visit, the provider should assess environmental triggers and comorbid conditions, review inhaler technique and adherence, and provide an updated asthma action plan. Inhaled corticosteroids remain the preferred controller in persistent childhood asthma; however, especially in young children, a discussion should occur with caregivers regarding possible adverse effects. Similarly, if long-acting beta-2-agonists are added to inhaled corticosteroids at step 3 care and above, the risk of severe asthma-related events should be discussed. Indications for referral to an asthma specialist include difficult-to-treat asthma, step 4 care and above, risk factors for severe asthma related events, subtypes of asthma, and doubts of asthma diagnosis.

Expression of recombinant Ara h 6 in Pichia pastoris but not in Escherichia coli preserves allergic effector function and allows assessment of specific mutations.

SCOPE: Ara h 6 has recently been recognized as an important peanut allergen. Recombinant allergens have been used for analysis of IgE binding, but have not been used to analyze the allergic effector activity that is more relevant to allergic reactions. METHODS AND RESULTS: Ara h 6 was expressed as a recombinant protein in both Escherichia coli and Pichia pastoris (rAra h 6-E. coli and rAra h 6-Pichia, respectively). Effector activity was assayed by measuring degranulation of RBL SX-38 cells sensitized with IgE from patients with severe peanut allergy. Compared to native Ara h 6 (nAra h 6), rAra h 6-Pichia had intact effector function whereas rAra h 6-E. coli had significantly reduced function. The lower effector activity in rAra h 6-E. coli compared to nAra h 6 and rAra h 6-Pichia did not appear to be due to differences in posttranslational modifications (analyzed by mass spectrometry and staining for carbohydrates) and may be due to subtle alteration(s) of folding seen on CD analysis and on nonreduced gels. Finally, we introduced point mutations in four important IgE-binding linear epitopes of Ara h 6 and found dramatically reduced allergic effector activity. CONCLUSION: Our studies demonstrate the utility of fully functional rAra h 6-Pichia as a starting point for analysis of specific mutations that adversely affect allergic effector function.