Pediatric Allergy and Immunology最新文献

Background: While food allergy (FA) has been increasingly recognized as a growing public health burden worldwide, epidemiological studies on FA in Japan are limited.

Methods: This was a noninterventional, observational study using the administrative claims data from 2010 to 2019 (10 years). Patients with physician-diagnosed FA in Japan (prevalent cohort) were divided into high-risk or low-risk cohorts using adrenaline prescription. The high-risk cohort was further divided into anaphylaxis or nonanaphylaxis cohort based on the occurrence of anaphylaxis or a serious allergic reaction (SAR) during 1 year after adrenaline prescription. The primary objective was to examine yearly prevalence of FA. The secondary objectives were to describe demographics/clinical characteristics and healthcare resource utilization (HCRU), to evaluate the number of occurrences of anaphylaxis/SAR in the high-risk cohort, and the impact of anaphylaxis/SAR on HCRU.

Results: The overall standardized prevalence rate was 0.325% (95% confidence interval [CI], 0.311-0.339) in 2010 and 0.797% (95% CI, 0.790-0.804) in 2019 and predominant in patients age <6 years (preschool; 3.377% [95% CI, 3.229-3.525] in 2010 and 5.726% [95% CI, 5.663-5.789] in 2019). Majority of FA patients (>80%) were children/adolescent throughout the 10 years. While high-risk cohort was a relatively minor population (8.5% in the prevalent cohort in 2019), the occurrence of anaphylaxis/SAR in the high-risk cohort was 227,690/100,000 patient-years. Multivariate analysis showed a significant increase in HCRU variables in the anaphylaxis versus nonanaphylaxis cohort (e.g., 2.08 [95% CI, 2.05-2.11] times more FA-related outpatient visits).

Conclusions: Prevalence of FA increased in a statistically significant way from 2010 to 2019; 1.7-fold increase was observed in patients <6 years old. Patients in the high-risk cohort appear to have suffered from frequent anaphylaxis/SAR, highlighting an unmet medical need for FA patients at "high-risk," considering the unavailability of approved medications to prevent anaphylaxis/SAR.

Basophil activation test (BAT) or the mast cell activation test (MAT) are two in vitro tests that are currently being studied in food allergy as diagnostic tools as an alternative to oral food challenges (OFCs). We conducted a meta-analysis on BAT and MAT, assessing their specificity and sensitivity in diagnosing peanut allergy. Six databases were searched for studies on patients suspected of having peanut allergy. Studies using BAT or MAT to peanut extract and/or component as diagnostic tools with results given in percentage of CD63 activation were included in this meta-analysis. Study quality was evaluated with the QUADAS-2 tool. On the 11 studies identified, eight focused exclusively on children, while three included a mixed population of adults and children. Only one study provided data on MAT, precluding us from conducting a statistical analysis. The diagnostic accuracy of BAT was higher when stimulated with peanut extract rather than Ara h 2 with a pooled specificity of 96% (95% CI: 0.89-0.98) and sensitivity of 0.86 (95% CI: 0.74-0.93). The sensitivity and specificity of BATs in discriminating between allergic and sensitized patients were studied as well, with pooled analysis revealing a sensitivity of 0.86 (95% CI: 0.74; 0.93) and a specificity of 0.97 (95% CI: 0.94, 0.98). BATs, when stimulated with peanut extracts, exhibit a satisfactory sensitivity and specificity for the diagnosis of peanut allergy and can help to discriminate between allergic individuals and those only sensitized to peanuts. More investigations on the potential for MATs diagnostic methods are warranted.

Background: Polymorphisms in susceptibility genes are a major risk factor for the development of asthma. Understanding these genetic variants helps elucidate asthma's pathogenesis, predict its onset, expedite antiasthma medication development, and achieve precise targeted individualized treatment. This study developed a test kit based on susceptibility genes for predicting asthma in Chinese children.

Methods: The present study constructed a VariantPro Targeted Library Preparation System with 72 single nucleotide polymorphism (SNP) loci associated with asthma from the ClinVar, OMIM, and SNPedia databases. These SNP loci were detected in the peripheral blood of 499 children with asthma and 500 healthy children. Significant differences were discovered for seven SNP loci. Simultaneously, whole exome sequencing of 46 children with asthma and 50 healthy children identified eight SNP loci with significant differences. The 15 SNP loci identified from Chinese children with asthma were validated in an independent population of 97 children with asthma and 93 healthy children by conducting multiplex polymerase chain reaction (PCR)-next-generation sequencing genotyping.

Results: Four loci (rs12422149, rs7216389, rs4065275, and rs41453444) were identified, and a single-tube multifluorescent qPCR (real-time quantitative PCR) test kit was developed using these four SNP loci. The kit was tested on 269 children with asthma and 724 children with bronchopneumonia.

Conclusions: We identified four loci as susceptibility genes and developed a quantitative PCR test kit for predicting asthma development in Chinese children.

Background: Recent advancements in molecular diagnostics have unveiled a multitude of allergen molecules (AMs) associated with animal sensitizations, revealing significant cross- and co-sensitization patterns among these seemingly distinct allergens.

Method: We investigated the sensitization profiles of 120 children, sensitized to at least one of the 14 AMs from cat, dog, or horse using the Alex test, employing correlations and hierarchical clusters to explore relationship between sensitizations.

Results: Sensitizations to Fel d 1, Can f 4/5, and Equ c 4 differ from other cat, dog, and horse AM sensitizations, suggesting they may represent genuine sensitizations for their respective animals. High correlations were observed among various AMs, including lipocalins (Can f 1/2/6, Fel d 4/7, and Equ c 1), serum albumins (Fel d 2, Can f 3, and Equ c 3), and uteroglobins (Fel d 1 and Can f_Fd1). Hierarchical clustering of sensitizations identified two similarity clusters and one dissimilarity cluster, providing an estimation of the likelihood of cross-reactivity. Additionally, our method facilitated speculation regarding cross-, co-, or genuine sensitization. Moreover, we noted a potential increase in the number and level of sensitized animal AMs concurrent with increased sensitization to other aeroallergens with advancing age. No significant difference was detected for the presence or absence of various types of allergic comorbidities.

Conclusion: Correlations and hierarchical clustering can unveil the extent and magnitude of cross-, co-, and genuine sensitization relationships among animal AMs. These insights can be leveraged to enhance artificial intelligence algorithms, improving diagnostic accuracy through the integration of other measures of sensitization.

Food allergies severely impact the health-related quality of life (HRQoL) of patients and their caregivers (family or informal caregivers). Currently there is no comprehensive review to provide an overview and critical assessment of the instruments in the field. Six databases were searched from inception until 10 August 2023, and a combination of subject terms and free words was used to search the literature. We used the COnsensus-based Standards for the selection of health Measurement INstruments methodology (COSMIN) to evaluate the measurement properties of the instruments. Forty-one studies reported on ten eligible instruments. Based on COSMIN guidelines, one instrument was recommended for Grade A, and the remaining nine instruments were recommended for Grade B. The Grade A instrument identified, the Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF), can help researchers assess the effectiveness of treatment for patients with food allergy and to understand the psychosocial impact of the disease on patients.

Background: There is increasing interest in elucidating the relationship between adenoid hypertrophy (AH) and allergic rhinitis (AR). However, the impact of aeroallergen sensitization patterns on children with AH and AR remains unclear.

Methods: Patients aged 2-8 years (recruited from January 2019 to December 2022) with nasal symptoms were assessed for allergies, adenoid size, and respiratory viral infection history. The serum total immunoglobulin E (IgE) and specific IgE levels were measured, and flexible nasal endoscopy was performed. The relationship between AH, aeroallergen sensitization patterns, and lymphocyte subpopulations in adenoid samples was analyzed using flow cytometry.

Results: In total, 5281 children were enrolled (56.5% with AR; and 48.6% with AH). AH was more prevalent in children with AR. Compared to nonsensitized individuals, those polysensitized to molds had a higher prevalence of AH (adjusted OR 1.61, 95% CI 1.32-1.96) and a greater occurrence of two or more respiratory viral infections, particularly in adenoidectomy patients. The percentages and corrected absolute counts of regulatory T (Treg) cells, activated Tregs, class-switched memory B cells (CSMBs), natural killer (NK) T cells, and NK cell subpopulations were reduced in the adenoid tissues of children with both AH and AR (AH-AR) compared to AH-nAR children. Polysensitization in AH-AR children correlated with lower CSMB percentages.

Conclusion: Polysensitivity to molds is associated with an increased risk of AH in children with AR. Fewer B cells, NK cells, and Treg cells with an effector/memory phenotype were detected in the adenoids of AR children, and these lower percentages of immune cells, particularly CSMBs, were closely linked to aeroallergen sensitization models and respiratory viral infection.

Background: Little is known about the immune responses during acute asthma exacerbation. In this study, we examined immune responses in children following an acute asthma exacerbation.

Methods: We evaluated pro-inflammatory cytokine levels and gene expression profiles in blood samples from pediatric patients admitted for acute asthma exacerbation. Viral PCR was performed to differentiate between viral or non-viral-associated exacerbations.

Results: Following informed consent, clinical data were obtained from 20 children with asthma (median [interquartile range, IQR]: age 11.5 [8.0, 14.2]) years and 14 healthy age-matched controls (10.5 [7.0, 13.0]). Twelve had positive nasopharyngeal Polymerase chain reaction (PCR) for viral infection (11 rhinoviruses and 1 respiratory syncytial virus (RSV)). Nine were in the pediatric intensive care unit (PICU) and among them five required continuous positive airway pressure (CPAP). Mean (±SD) days on systemic steroids before drawing blood sample were 2.5 ± 1.6. Twelve had history of environmental allergies with 917 (274, 1396) IU/mL total IgE (median (IQR)). Compared with controls, IL-1RA and IL-10 levels were significantly increased and TNF-α significantly decreased in asthma subjects (p < .05 for all). RNA-seq analysis revealed 852 differentially expressed genes in subjects with asthma. Pathway analysis found upregulated genes and pathways involved in innate immune responses in subjects with asthma. Significantly reduced genes included pathways associated with T helper cell differentiation and activation.

Conclusions: In acute asthma exacerbation, innate immune pathways remained increased while adaptive immune responses related to T helper cells are blunted and are independent of trigger or asthma severity. Our novel findings highlight the need to identify new therapies to target persistent innate immune responses to improve outcomes in acute asthma.

Background: Respiratory Syncytial Virus (RSV) is the leading cause of hospitalization in infants. RSV bronchiolitis is associated with an increased risk of subsequent wheezing. We aimed to document the parents' perception of the link between RSV infection and subsequent wheezing, wheezing-related healthcare and family resources use, and its impact on family daily life.

Methods: This cross-sectional online survey enrolled 1200 parents with at least one child ≤6y living in the United States, United Kingdom, Spain, and Italy. Children diagnosed with RSV bronchiolitis before age of 2 years were included in the RSV group, and those never diagnosed with RSV bronchiolitis in the Reference group.

Results: The odds of wheezing were 4.5-fold (95%CI 3.5-5.9) higher in the RSV than in the Reference group. The odds increased to 7.7-fold (95%CI 5.4-11.1) among children who were hospitalized, and 9-fold (95%CI 5.1-16.6) among those admitted to pediatric intensive care with RSV bronchiolitis. Similar trends were observed across all countries. In total, 57% of parents reported their child's wheezing to have moderate to severe impact on their emotional well-being, and 53% on their daily life activities and/or social life. 64% of parents reported moderate-severe impact of wheezing on child's quality of sleep and 49% and 46% reported a moderate-severe impact on their children's emotional well-being and physical activities.

Conclusions: This survey suggests an association between RSV infection and subsequent wheezing in children across different countries. Wheezing, especially in association with RSV infection, was associated with increased healthcare utilization and costs, and significantly impacted parents' and children daily life.

Background: Several clinical trials have shown that nirsevimab, an antibody targeting the respiratory syncytial virus (RSV), reduces RSV bronchiolitis requiring admission. In 2023-2024, Catalonia and Andorra adopted immunization strategies for children <6 months and those born during the epidemic season. This study evaluates the effectiveness of nirsevimab in preventing hospitalizations from RSV bronchiolitis.

Methods: In the epidemic season of 2023-2024, a test-negative case-control study was conducted in three hospitals from Catalonia and Andorra. Patients <12 months old admitted with bronchiolitis and tested for RSV using molecular microbiology tests were included. The effectiveness in preventing RSV bronchiolitis hospitalization and severe disease was estimated using multivariate models. Comparisons between immunized, non-immunized, and non-eligible patients were made in prospectively collected epidemiological, clinical, and microbiological variables.

Results: Two hundred thirty-four patients were included. RSV was detected in 141/234 (60.2%), being less common in the immunized group (37% vs 75%, p < .001). The rate of immunized patients among those eligible was 59.7%. The estimated effectiveness for RSV-associated lower respiratory tract infection was 81.0% (95% confidence interval: 60.9-90.7), and for preventing severe disease (the need for NIV/CMV), 85.6% (41.7-96.4%). No significant differences by immunization status were observed in patients with RSV concerning viral coinfections, the need for NIV/CMV or length of hospital stay.

Conclusions: This study provides real-world evidence of the effectiveness of nirsevimab in preventing RSV-lower respiratory tract infection hospitalization and severe disease in infants during their first RSV season following a systematic immunization program. Immunized patients did not exhibit a higher rate of viral coinfections nor differences in clinical severity once admitted.

Background: Atopic dermatitis (AD) is frequently associated with asthma and allergic rhinitis (AR). Dupilumab is an effective treatment for pediatric AD, although the effect on atopic comorbidities in pediatric AD patients is limited.

Objective: To investigate the prevalence of asthma and AR in pediatric AD patients starting dupilumab treatment and to evaluate the effect of dupilumab on these comorbidities.

Methods: This study included pediatric AD patients (aged 3-17 years) treated with dupilumab between 2019 and 2023. Patients were screened at baseline by a pulmonologist for the presence of asthma and AR. Screening included evaluation of medical history and current symptoms, spirometry (including Forced Expiratory Volume in 1 s (FEV₁)), Fractional exhaled Nitric Oxide (FeNO), and measurement of aeroallergen-specific IgE levels. In patients diagnosed with comorbid asthma and/or AR, measurements were repeated at weeks 16 and 52. Spirometry measurements, FeNO, and aeroallergen-specific IgE levels during treatment were analyzed using a covariance pattern model.

Results: Eighty-four patients were included. Asthma was diagnosed in 50 patients (59.5%) and AR in 72 patients (85.7%). Baseline FeNO levels were elevated in both patients with (29.0 ppb (95% CI 22.0-54.0)) and without asthma (26.0 ppb (95% CI 22.0-30.0)). During treatment, FeNO levels decreased (p < .001) and FEV₁ scores increased (p < .001) in patients with asthma. In patients with asthma and/or AR, all aeroallergen-specific IgE levels decreased between 61.3% and 89.1% at 52 weeks of treatment.

Conclusion: One year of dupilumab treatment, primarily indicated for AD, resulted in a significant improvement in comorbid asthma and a profound decrease in aeroallergen-specific IgE levels in patients with asthma and/or AR.