Human germline heterozygous gain-of-function STAT6 variants cause severe allergic disease.

STAT6 (signal transducer and activator of transcription 6) is a transcription factor that plays a central role in the pathophysiology of allergic inflammation. We have identified 16 patients from 10 families spanning three continents with a profound phenotype of early-life onset allergic immune dysregulation, widespread treatment-resistant atopic dermatitis, hypereosinophilia with esosinophilic gastrointestinal disease, asthma, elevated serum IgE, IgE-mediated food allergies, and anaphylaxis. The cases were either sporadic (seven kindreds) or followed an autosomal dominant inheritance pattern (three kindreds). All patients carried monoallelic rare variants in STAT6 and functional studies established their gain-of-function (GOF) phenotype with sustained STAT6 phosphorylation, increased STAT6 target gene expression, and TH2 skewing. Precision treatment with the anti-IL-4Rα antibody, dupilumab, was highly effective improving both clinical manifestations and immunological biomarkers. This study identifies heterozygous GOF variants in STAT6 as a novel autosomal dominant allergic disorder. We anticipate that our discovery of multiple kindreds with germline STAT6 GOF variants will facilitate the recognition of more affected individuals and the full definition of this new primary atopic disorder.

Food Allergy Management for Adolescents Using Behavioral Incentives: A Randomized Trial.

OBJECTIVE: We sought to evaluate the use of behavioral economics approaches to promote the carrying of epinephrine auto-injectors (EAIs) among adolescents with food allergies. We hypothesized that adolescents who receive frequent text message nudges (Intervention 1) or frequent text message nudges plus modest financial incentives (Intervention 2) would be more likely to carry their epinephrine than members of the usual care control group. METHODS: We recruited 131 adolescents ages 15 to 19 with a food allergy and a current prescription for epinephrine to participate in a cohort multiple randomized controlled trial. Participants were randomly assigned to participate in Intervention 1, Intervention 2, or to receive usual care. The primary outcome was consistency of epinephrine-carrying, measured as the proportion of checkpoints at which a participant could successfully demonstrate they were carrying their EAI, with photo-documentation of the device. RESULTS: During Intervention 1, participants who received the intervention carried their EAI 28% of the time versus 38% for control group participants (P = .06). During Intervention 2, participations who received the intervention carried their EAI 45% of the time versus 23% for control group participants (P = .002). CONCLUSIONS: Text message nudges alone were unsuccessful at promoting EAI-carrying but text message nudges combined with modest financial incentives almost doubled EAI-carriage rates among those who received the intervention compared with the control group. However, even with the intervention, adolescents with food allergies carried their EAI <50% of the time. Alternative strategies for making EAIs accessible to adolescents at all times should be implemented.

Improvement in eosinophilic esophagitis when using dupilumab for other indications or compassionate use.

BACKGROUND: Dupilumab has been approved to treat atopic dermatitis, asthma, and nasal polyps and is in active clinical trials for the treatment of eosinophilic esophagitis (EoE). Given its shared immunopathology, we hypothesized that EoE symptoms and inflammation would improve when dupilumab therapy was used for other allergic indications. OBJECTIVE: To measure the clinical and histologic response in EoE to dupilumab when treating other atopic diseases. METHODS: We completed a retrospective chart review of all patients at Children's Hospital of Philadelphia and Rady Children Hospital who were prescribed dupilumab for atopic dermatitis, asthma, or nasal polyps and had a concomitant clinical diagnosis of EoE. Demographic information along with histology, symptom scores, medications, and diet information were collected. Response to dupilumab was evaluated. RESULTS: A total of 45 patients were identified. Of which, 11 patients were prescribed dupilumab for asthma, 27 for atopic dermatitis, 3 for nasal polyps, and 4 for compassionate use for EoE. There was no follow-up data for 8 patients. Follow-up histology was available for 26 patients: 22 of 26 had less than 6 eosinophils per high power field after the initiation of dupilumab with significant improvement (pre: 52.9 + 35.1 to post: 4.5 + 10.9 eosinophils/high power field, P < .005). A total of 28 patients had improvement of symptoms, with 24 patients reporting complete resolution of symptoms after dupilumab initiation. Reductions in EoE treatment medications (swallowed steroids, proton pump inhibitors) or expansion of diet occurred in 29 patients treated with dupilumab. CONCLUSION: Dupilumab therapy initiated for atopic disease effectively induces symptomatic and histologic remission of esophageal disease and reduces the need for EoE-directed therapy in patients with concomitant EoE.

Safety of Epicutaneous Immunotherapy in Peanut-Allergic Children: REALISE Randomized Clinical Trial Results.

BACKGROUND: Treatment options for peanut allergy are limited. In previous clinical trials, epicutaneous immunotherapy with a patch containing 250-µg peanut protein (Viaskin Peanut 250 µg [VP250]) was well tolerated and statistically superior to placebo in desensitizing peanut-allergic children. OBJECTIVE: To examine the safety of VP250 in children, using a study design approximating potential real-world use. METHODS: REAL LIfe Use and Safety of EPIT (REALISE) is a phase 3 multicenter study consisting of a 6-month, randomized, double-blind, placebo-controlled period followed by open-label active treatment. Children aged 4 to 11 years with physician diagnosis of peanut allergy received daily treatment with placebo (6 months) or VP250 (up to 36 months). Data from the 6-month, randomized, controlled phase of REALISE are reported. RESULTS: Three hundred ninety-three children were randomized 3:1 to receive VP250 (n = 294) or placebo (n = 99) for 6 months; 284 (72.3%) children had a history of peanut anaphylaxis. According to parent diary, all participants receiving VP250 and 83.8% receiving placebo reported at least 1 episode of local skin reaction, with frequency decreasing over time. Only 4 participants (1.4%) receiving VP250 discontinued because of adverse events (AEs). Epinephrine was administered for allergic reactions attributed to VP250 in 7 children (2.4%), of whom 5 remained in the study; none involved severe anaphylaxis. Overall, AE rates were similar among participants with and without a history of peanut anaphylaxis. CONCLUSIONS: In a study designed to mirror real-world use, VP250 was observed to be well tolerated in peanut-allergic children, consistent with previous phase 2b and 3 studies.

Food protein-induced enterocolitis syndrome oral food challenge: Time for a change?

OBJECTIVE: Food protein-induced enterocolitis syndrome (FPIES) is typically diagnosed based on a characteristic clinical history; however, an oral food challenge (OFC) may be necessary to confirm the diagnosis or evaluate for the development of tolerance. FPIES OFC methods vary globally, and there is no universally agreed upon protocol. The objective of this review is to summarize reported FPIES OFC approaches and consider unmet needs in diagnosing and managing FPIES. DATA SOURCES: PubMed database was searched using the keywords food protein-induced enterocolitis syndrome, oral food challenge, cow milk allergy, food allergy, non-immunoglobulin E-mediated food allergy and FPIES. STUDY SELECTIONS: Primary and review articles were selected based on relevance to the diagnosis of FPIES and the FPIES OFC. RESULTS: We reviewed the history of FPIES and the evolution and variations in the FPIES OFC. A summary of current literature suggests that most patients with FPIES will react with 25% to 33% of a standard serving of the challenged food, there is little benefit to offering a divided dose challenge unless there is suspicion of specific immunoglobulin E to the food being challenged, reactions typically appear within 1 to 4 hours of ingestion, and reactions during OFC rarely result in emergency department or intensive care unit admission. CONCLUSION: International standardization in the FPIES OFC approach is necessary with particular attention to specific dose administration across challenged foods, timing between the patient's reaction and offered OFC to verify tolerance, patient safety considerations before the OFC, and identification of characteristics that would indicate home reintroduction is appropriate.

Elevated Atopic Comorbidity in Patients with Food Protein-Induced Enterocolitis.

BACKGROUND: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy. Its relationship to the major atopic manifestations (atopic dermatitis [AD], IgE-mediated food allergy [IgE-FA], allergic rhinitis [AR], asthma) is not understood. OBJECTIVE: To determine the clinical characteristics, epidemiologic features, and natural history of FPIES in relation to the major atopic manifestations. METHODS: We examined our primary care birth cohort of 158,510 pediatric patients, of whom 214 patients met 2017 FPIES diagnostic criteria. We measured the influence of FPIES on developing subsequent atopic disease. RESULTS: Pediatric FPIES incidence was between 0.17% and 0.42% depending on birth year. As in prior reports, most patients had an acute presentation (78%), and milk, soy, oat, rice, potato, and egg were common triggers. The mean age of diagnosis was 6.8 months. Atopic comorbidity was higher in patients with FPIES compared with healthy children (AD, 20.6% vs 11.7%; IgE-FA, 23.8% vs 4.0%; asthma, 26.6% vs 18.4%; AR, 28.0% vs 16.7%; P < .001 χ2). However, longitudinal analyses indicated that prior FPIES did not influence the rate of atopy development. CONCLUSIONS: The incidence of FPIES in our cohort was initially low, but is increasing. Food allergen distribution, presentation, and age of onset are similar to prior reports. Patients with FPIES have high rates of atopic comorbidity. However, longitudinal analysis does not support direct causation as the etiology of these associations. Rather it suggests a shared predisposition to both types of allergy, or associative bias effects. This work refines our understanding of the natural history of FPIES by elucidating associations between FPIES and atopy.

Food Protein-Induced Enterocolitis Syndrome Food Challenges: Experience from a Large Referral Center.

BACKGROUND: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy that is diagnosed based on clinical findings, but can be confirmed with oral food challenge (OFC). OFC is more often performed to assess the development of tolerance. Most studies describing OFCs in FPIES are limited in size. OBJECTIVE: We sought to describe our experience with OFCs using our FPIES protocol. Patients were given one-third of serving size with a 4-hour observation period, followed by home titration to full dose. METHODS: We conducted a retrospective chart review of patients who underwent OFC via the FPIES protocol from 2014 to 2017. Data regarding the history of reaction, age at the time of challenge, and reactions during challenge or with home introduction were collected. RESULTS: A total of 169 OFCs were completed under the FPIES protocol, in 119 patients to 19 different foods. Thirty challenges (18%) were positive, with 17 challenges (10%) during initial challenge and 13 (7.7%) during home dosing. Most reactions during initial challenge required intravenous fluids (IVF), but hypotension was uncommon. One hundred thirty-nine (82%) OFCs were negative with home introduction, indicating tolerance to the challenged foods. The mean age of passing a challenge to milk, soy, and grain was earlier than that of other solid foods. CONCLUSIONS: Our data suggest that our FPIES OFC protocol is safe. Early administration of IVF may prevent the development of hypotension. It is difficult to stratify the risk of severe or delayed reaction based on patient characteristics, and more data are needed to identify those appropriate for home introduction.

Improving allergy office scheduling increases patient follow up and reduces asthma readmission after pediatric asthma hospitalization.

BACKGROUND: Pediatric asthma is a major contributor to emergency room utilization and hospital readmission rates. OBJECTIVE: To develop an allergy department‒based intervention to improve follow-up appointment scheduling processes for pediatric asthma patients after discharge for asthma exacerbation. METHODS: This quality improvement study was conducted in the allergy clinic of an urban, tertiary children's hospital. Children receiving subspecialty allergy care for asthma were included into the intervention group during the intervention period. The quality improvement intervention consisted of 3 attempts by telephone to reach the family to schedule the follow-up appointment. If this was unsuccessful or if the appointment was not kept, then a reminder letter was sent to the family. The primary outcome of interest in this study was the percent of postdischarge follow-up appointments scheduled within 30 days of discharge. Secondary outcomes measured were the percent of allergy appointments attended within 30 days of discharge and the 30-day hospital readmission rate. RESULTS: Demographics did not differ significantly between the intervention and baseline preintervention year. The initial baseline scheduled allergy follow-up visit rate was 48.8 ± 13.3% of patients discharged per month. This increased to an overall rate of 75.7 ± 20.1% patients scheduling allergy follow-up within 30 days of discharge during the intervention year. We also observed a significant increase in attended allergy visits 30 days postdischarge from 35.5 ± 15.6% in year 1 to 53.9 ± 25.5% during the intervention year and a significant decrease in the 30-day readmission rate on the allergy service. CONCLUSION: These data suggests that minor changes in allergy practice organization can significantly affect posthospitalization follow-up rates and decrease asthma readmission rates.

Medication contaminants as a potential cause of anaphylaxis to vincristine.

Vincristine (VCR) is a vinca alkaloid and common chemotherapeutic that is used to treat multiple pediatric and adult malignancies. Despite its common use, cases of anaphylaxis to VCR are rare and typically isolated to a single individual. We report a series of eight patients with adverse reactions to VCR over the course of 11 months at a single institution, four of which progressed to anaphylaxis and one of which resulted in cardiac arrest. Mass spectrometry analysis of medication lots was performed to test for possible contaminant(s). Our findings highlight the risk of anaphylaxis during therapy with VCR.

Effect of Varying Doses of Epicutaneous Immunotherapy vs Placebo on Reaction to Peanut Protein Exposure Among Patients With Peanut Sensitivity: A Randomized Clinical Trial.

Importance: Epicutaneous immunotherapy may have potential for treating peanut allergy but has been assessed only in preclinical and early human trials. Objective: To determine the optimal dose, adverse events (AEs), and efficacy of a peanut patch for peanut allergy treatment. Design, Setting, and Participants: Phase 2b double-blind, placebo-controlled, dose-ranging trial of a peanut patch in peanut-allergic patients (6-55 years) from 22 centers, with a 2-year, open-label extension (July 31, 2012-July 31, 2014; extension completed September 29, 2016). Patients (n = 221) had peanut sensitivity and positive double-blind, placebo-controlled food challenges to an eliciting dose of 300 mg or less of peanut protein. Interventions: Randomly assigned patients (1:1:1:1) received an epicutaneous peanut patch containing 50 µg (n = 53), 100 µg (n = 56), or 250 µg (n = 56) of peanut protein or a placebo patch (n = 56). Following daily patch application for 12 months, patients underwent a double-blind, placebo-controlled food challenge to establish changes in eliciting dose. Main Outcomes and Measures: The primary efficacy end point was percentage of treatment responders (eliciting dose: ≥10-times increase and/or reaching ≥1000 mg of peanut protein) in each group vs placebo patch after 12 months. Secondary end points included percentage of responders by age strata and treatment-emergent adverse events (TEAEs). Results: Of 221 patients randomized (median age, 11 years [quartile 1, quartile 3: 8, 16]; 37.6% female), 93.7% completed the trial. A significant absolute difference in response rates was observed at month 12 between the 250-µg (n = 28; 50.0%) and placebo (n = 14; 25.0%) patches (difference, 25.0%; 95% CI, 7.7%-42.3%; P = .01). No significant difference was seen between the placebo patch vs the 100-µg patch. Because of statistical testing hierarchical rules, the 50-µg patch was not compared with placebo. Interaction by age group was only significant for the 250-µg patch (P = .04). In the 6- to 11-year stratum, the response rate difference between the 250-µg (n = 15; 53.6%) and placebo (n = 6; 19.4%) patches was 34.2% (95% CI, 11.1%-57.3%; P = .008); adolescents/adults showed no difference between the 250-µg (n = 13; 46.4%) and placebo (n = 8; 32.0%) patches: 14.4% (95% CI, -11.6% to 40.4%; P = .40). No dose-related serious AEs were observed. The percentage of patients with 1 or more TEAEs (largely local skin reactions) was similar across all groups in year 1: 50-µg patch = 100%, 100-µg patch = 98.2%, 250-µg patch = 100%, and placebo patch = 92.9%. The overall median adherence was 97.6% after 1 year; the dropout rate for treatment-related AEs was 0.9%. Conclusions and Relevance: In this dose-ranging trial of peanut-allergic patients, the 250-µg peanut patch resulted in significant treatment response vs placebo patch following 12 months of therapy. These findings warrant a phase 3 trial. Trial Registration: clinicaltrials.gov Identifier: NCT01675882.

The immune deficiency of chromosome 22q11.2 deletion syndrome.

The syndrome originally described by Dr. Angelo DiGeorge had immunodeficiency as a central component. When a 22q11.2 deletion was identified as the cause in the majority of patients with DiGeorge syndrome, the clinical features of 22q11.2 deletion syndrome became so expansive that the immunodeficiency became less prominent in our thinking about the syndrome. This review will focus on the immune system and the changes in our understanding over the past 50 years. Initially characterized as a pure defect in T cell development, we now appreciate that many of the clinical features related to the immunodeficiency are well downstream of the limitation imposed by a small thymus. Dysfunctional B cells presumed to be secondary to compromised T cell help, issues related to T cell exhaustion, and high rates of atopy and autoimmunity are aspects of management that require consideration for optimal clinical care and for designing a cogent monitoring approach. New data on atopy are presented to further demonstrate the association.

Seasonal exacerbation of esophageal eosinophilia in children with eosinophilic esophagitis and allergic rhinitis.

BACKGROUND: Evidence supports a possible link between eosinophilic esophagitis (EoE) and environmental aeroallergens, which can manifest as seasonal exacerbation of esophageal eosinophilia. Few studies have examined this link in pediatric patients with EoE. OBJECTIVE: To identify the proportion of patients with seasonal induced esophageal eosinophilia. METHODS: A retrospective chart review was conducted of all patients diagnosed with EoE at the authors' institution. Demographic data were collected by chart review. Seasonal variation or flare was defined as a change from fewer than to at least 15 eosinophils per high-power field and a minimum of a 2-fold increase in eosinophil count between 2 consecutive biopsy specimens in different seasons without dietary or medication modifications. RESULTS: Of the 1,180 patients with EoE, 160 (14%) were suspected of having aeroallergen-associated triggers by history. Of these 160 patients, 32 (20%) had biopsy examination-confirmed variation of EoE triggered by aeroallergens. Most of these patients were boys (84%), all had a history or examination consistent with allergic rhinitis, and most had a history of asthma (75%). Thirty-two subjects had obvious seasonal variation, 22 of whom also had known food-induced symptoms. CONCLUSION: Children with EoE and allergic rhinitis might have exacerbations in their esophageal eosinophilia during certain seasons depending on the specific aeroallergens to which they are sensitized. Identification of environmental allergens to sensitized patients is important and can guide therapy.