1980–2019년 기간 동안 소아청소년 알레르기질환에서 항원 감작의 변화

Purpose Allergen sensitization is constantly changing, and understanding these changes can help manage and prevent allergic diseases. This research analyzed and compared the changes in allergen sensitization in children diagnosed with allergic diseases using the skin test and the multiple allergen simultaneous test. Methods We retrospectively analyzed the data on children who were diagnosed with allergic diseases and received immunotherapy at Yonsei Medical Center from 1980 to 1998 and they were screened for allergen sensitization at Severance Hospital from 2005 to 2019. Results Between 1980 and 1998, and between 2005 and 2019, data on 3,205 (male, 70.3%; mean age, 7.2±2.9 years) and 15,318 children (male, 62.8%; mean age, 8.8±4.5 years) were analyzed. The sensitized allergens that appeared in the 1980–1998 included Dermatophagoides farinae (91.0%), Dermatophagoides pteronyssinus (76.3%), cockroach (13.5%), and Alternaria (11.5%), in order of frequency; further, the sensitized allergens that appeared in the 2005–2019 included D. farinae (45.0%), D. pteronyssinus (39.6%), cat dander (12.2%), and dog dander (9.1%), in order of frequency. D. farinae and D. pteronyssinus demonstrated the highest sensitization rates, although the rates decreased gradually. The sensitization to cat dander and dog dander showed a growing trend, and sensitization to Humulus japonicus, Candida, and cockroach decreased after 2005. Conclusion Over the past 40 years, the allergen sensitization in Korean children with allergic diseases has increased. These changes reflect lifestyle and environmental changes and influence allergic disease management approaches. Thus, changes in allergic sensitization should be monitored continuously.ope

Pediatric Home Mechanical Ventilation in Korea: the Present Situation and Future Strategy

BACKGROUND: The number of children using home mechanical ventilation (HMV) has increased markedly in Europe and North America, but little is known about the situation in Korea. We described the clinical characteristics of children using HMV and investigated the current situation of HMV utilization in children. METHODS: Data on HMV prescriptions in year 2016 for children under the age of 19 was retrieved from the National Health Insurance Service for nationwide information. For more detailed information, data from year 2016 to 2018 was also retrieved from a tertiary center, Severance Children's Hospital. RESULTS: Nationwide, 416 children were prescribed with HMV in 2016, with an estimated prevalence of 4.4 per 100,000 children, of which 64.2% were male and mean age was 6-year-old. The estimated number of patients using invasive ventilators via tracheostomy was 202 (49%). Neuromuscular diseases were the most frequent cause (217; 52%), followed by central nervous system diseases (142; 34%), and cardiopulmonary diseases (57; 14%). In the tertiary center, a total of 62 children were prescribed with HMV (19 [31%] with non-invasive ventilation; 43 [69%] with invasive ventilation]. The number of children with HMV increased from 11 in 2016 to 29 in 2018. The mean age for initiation of HMV was 3.1 years and male patients comprised 65%. The most frequent diagnostic reason for HMV was central nervous system diseases (68%), followed by cardiopulmonary diseases (19%) and neuromuscular diseases (13%). Five patients died during the study period and five patients weaned from HMV. CONCLUSION: This study provides insights on the present situation of HMV utilization in Korean children.ope

P50 implies adverse clinical outcomes in pediatric acute respiratory distress syndrome by reflecting extrapulmonary organ dysfunction

Hypoxemia and multiple organ dysfunction are significant contributors to mortality in patients with pediatric acute respiratory distress syndrome (PARDS). P50, the oxygen tension at which hemoglobin is 50% saturated, is a measure of hemoglobin-oxygen affinity, and its alteration might have implications for tissue hypoxia and organ dysfunction. The purpose of this single-center, retrospective study was to evaluate P50 levels in PARDS and to determine the association between P50 and clinical outcomes. The study included 212 children diagnosed with PARDS according to the Pediatric Acute Lung Injury Consensus Conference definition who required invasive mechanical ventilation and had arterial blood gas results of hemoglobin oxygen saturation < 97% at the time of diagnosis. P50 levels were calculated using Doyle's method, and organ dysfunction was assessed using the Pediatric Logistic Organ Dysfunction-2 score. Most patients exhibited more than one dysfunctional extrapulmonary organ at PARDS onset. P50 increased with increasing PARDS severity (mild (26.6 [24.9-29.6]), moderate (26.8 [25.0-29.5]), and severe PARDS (29.1 [26.1-32.4] mmHg; P = 0.025). Moreover, P50 demonstrated a significant positive association with extrapulmonary organ dysfunction score (β = 0.158, P = 0.007) and risk of mortality (adjusted hazard ratio, 1.056; 95% confidence interval, 1.015-1.098; P = 0.007), irrespective of initial PARDS severity. The relationship between P50 and mortality was largely mediated by extrapulmonary organ dysfunction. A high P50 value at the time of PARDS diagnosis may be associated with mortality via dysfunctional extrapulmonary organs. Future studies should consider P50 as a potential candidate index for risk stratification of PARDS patients.ope

Gram-negative microbiota is related to acute exacerbation in children with asthma

Background: The upper-airway microbiota may be associated with the pathogenesis of asthma and useful for predicting acute exacerbation. However, the relationship between the lower-airway microbiota and acute exacerbation in children with asthma is not well understood. We evaluated the characteristics of the airway microbiome using induced sputum from children with asthma exacerbation and compared the microbiota-related differences of inflammatory cytokines with those in children with asthma. Methods: We analysed the microbiome using induced sputum during acute exacerbation of asthma in children. We identified microbial candidates that were prominent in children with asthma exacerbation and compared them with those in children with stable asthma using various analytical methods. The microbial candidates were analysed to determine their association with inflammatory cytokines. We also developed a predictive functional profile using PICRUSt. Results: A total of 95 children with allergic sensitisation including 22 with asthma exacerbation, 67 with stable asthma, and 6 controls were evaluated. We selected 26 microbial candidates whose abundances were significantly increased, decreased, or correlated during acute exacerbation in children with asthma. Among the microbial candidates, Campylobacter, Capnocytophaga, Haemophilus, and Porphyromonas were associated with inflammatory cytokines including macrophage inflammatory protein (MIP)-1β, programmed death-ligand 1, and granzyme B. Both Campylobacter and MIP-1β levels were correlated with sputum eosinophils. Increased lipopolysaccharide biosynthesis and decreased glycan degradation were observed in children with asthma exacerbation. Conclusion: Gram-negative microbes in the lower airway were related to acute exacerbation in children with asthma. These microbes and associated cytokines may play a role in exacerbating asthma in children.ope

Genome-wide association study identifies BTNL2 associated with atopic asthma in children

Asthma is a heterogeneous disease characterized by chronic airway inflammation with a genetic predisposition. Butyrophilin-like 2 (BTNL2) is a member of the immunoglobulin superfamily that plays an important role in regulating T cell activation and immune homeostasis. Here, we aimed to investigate the association of the genetic variants of BTNL2 with childhood asthma and asthma-related traits by utilizing extreme asthma phenotypes and employing a genome-wide association study. Our study included 243 children with well-defined moderate to severe atopic asthma and 134 healthy children with no history of allergic diseases and allergic sensitization. DNA from these subjects was genotyped using AxiomTM Genome-Wide Array Plates. Although no single nucleotide polymorphisms (SNPs) reached a genome-wide threshold of significance, 3 SNPs, rs3817971, rs41355746, and rs41441651, at BTNL2 were significantly associated with moderate to severe atopic asthma after performing Bonferroni correction. These SNPs were also associated with the risk of allergic sensitization toward house dust mites and the presence and degree of bronchial hyperresponsiveness. Thus, we identified that BTNL2 was associated with atopic moderate to severe persistent asthma in Korean children, and this may play an important role in disease development and susceptibility.ope

SpO 2/FiO 2 as a predictor of high flow nasal cannula outcomes in children with acute hypoxemic respiratory failure

The high-flow nasal cannula (HFNC) is a useful treatment modality for acute hypoxemic respiratory failure (AHRF) in children. We compared the ability of the oxygen saturation to fraction of inspired oxygen ratio (S/F) and arterial oxygen partial pressure to fraction of inspired oxygen ratio (P/F) to predict HFNC outcomes in children with AHRF. This study included children treated with HFNC due to AHRF from April 2013 to March 2019 at the Severance Children's Hospital. HFNC failure was defined as the need for mechanical ventilation. Trends of S/F and P/F during HFNC were analyzed. To predict HFNC outcomes, a nomogram was constructed based on predictive factors. A total of 139 patients with arterial blood gas data were included in the S/F and P/F analyses. S/F < 230 at initiation showed high prediction accuracy for HFNC failure (area under the receiver operating characteristic curve: 0.751). Univariate analyses identified S/F < 230 at HFNC initiation and < 200 at 2 h (odds ratio [OR] 12.83, 95% CI 5.06-35.84), and hemato-oncologic disease (OR 3.79, 95% CI 1.12-12.78) as significant predictive factors of HFNC failure. The constructed nomogram had a highly predictive performance, with a concordance index of 0.765 and 0.831 for the exploratory and validation groups, respectively. S/F may be used as a predictor of HFNC outcomes. Our nomogram with S/F for HFNC failure within 2 h may prevent delayed intubation in children with AHRF.ope

Children with Heiner Syndrome: A Single-Center Experience

Heiner syndrome is a rare cause of pulmonary hemosiderosis in children that is triggered by cow's milk allergy. Herein, we describe our experience with three recent cases of Heiner syndrome with diverse clinical courses. We recommend that clinicians should consider the possibility of Heiner syndrome in children who exhibit characteristics of idiopathic pulmonary hemosiderosis.ope

Development of a Multidisciplinary Aerodigestive Program: An Institutional Experience

We share our experience on the implementation of a multidisciplinary aerodigestive program comprising an aerodigestive team (ADT) so as to evaluate its feasibility. We performed a retrospective chart review of the patients discussed at the monthly ADT meetings and analyzed the data. A total of 98 children were referred to the ADT during the study period. The number of cases increased steadily from 3.5 cases per month in 2019 to 8.5 cases per month in 2020. The median age of patients was 34.5 months, and 55% were male. Among the chronic comorbidities, neurologic disease was the most common (85%), followed by respiratory (36%) and cardiac (13%) disorders. The common reasons for consultation were suspected aspiration (56%), respiratory difficulty (44%), drooling/stertor (30%), regurgitation/vomiting (18%), and feeding/swallowing difficulty (17%). Following discussions, 58 patients received active interventions, including fundoplication, gastrostomy, laryngomicrosurgery, tracheostomy, and primary dilatation of the airway. According to the questionnaire of the caregiver, the majority agreed that the main symptoms and quality of life of patients had improved (88%), reducing the burden on caregivers (77%). Aerodigestive programs may provide comprehensive and multidisciplinary management for children with complex airway and digestive tract disorders.ope

Multidisciplinary aerodigestive program at a children's hospital: A protocol for a prospective observational study

Background: Children with complex chronic multisystemic diseases frequently require care from multiple pediatric subspecialists. The aerodigestive program is a multidisciplinary program that diagnoses and treats pediatric patients with complex multi-systematic problems affecting airway, breathing, feeding, swallowing, or growth. The aim of this study is to present the protocol of the aerodigestive program of a children's hospital. Methods and design: This study is a prospective study to evaluate and compare the overall improvement of patients' objective and subjective conditions before and after the AeroDigestive Team (ADT) program. Among children from 1 month to 18 years of age, patients with complex problems of the airway, breathing, feeding, swallowing, or growth meeting at least two parameters of the inclusion criteria were enrolled. The overall process included referral based on the inclusion criteria, enrollment of ADT program with informed consents, interview and questionnaire for assessing patients' medical condition, prescheduling appointment, multi-specialists' evaluation, monthly team meetings, wrap-up discussion with the patients and family, therapeutic intervention, and follow-up at 6 months with the assessment of outcome measures. The outcome was evaluated objectively and subjectively. The objective outcome measure was divided into surgical or medical intervention, assessment of changes in medical condition, and follow-up study. Both caregiver interviews and questionnaires using a scoring system were used as subjective outcome measures before and after the ADT program. Children were scheduled to be followed-up at 6 months after the interventions or ADT meeting. Discussion: The aerodigestive program is expected to provide comprehensive and multidisciplinary management of children with complex airway and digestive tract disorders.ope