Psychological Distress and Perceived Burden in Parents of Korean Children With IgE-Mediated Food Allergy

Background@#Food allergy (FA) can have a profound effect on quality of life (QoL), stress, and anxiety in the family. We aimed to validate the Korean version of the Food Allergy Quality of Life-Parental Burden (FAQL-PB) and identify factors related to the parental psychosocial burden of caring for children with FAs. @*Methods@#Parents of children aged between 6 months and 17 years with immunoglobulin E (IgE)-mediated FAs from the Pediatric Allergy Department of five university hospitals in Korea were enrolled in the study. Parents were asked to complete the FAQL-PB, Food Allergy Independent Measure-Parent Form (FAIM-PF), Child Health Questionnaire-Parents Form 28 (CHQ-PF28), Beck’s Anxiety Inventory, Connor-Davidson Resilience Scale, and Patient Health Questionnaire-9 for depression. Statistical analyses included internal consistency, test-retest reliability, concurrent validity, discriminative validity, and logistic regression analyses. @*Results@#A total of 190 parents were enrolled. Social activity limitation was the item with the highest FAQL-PB scores. The Cronbach’s α for each item was higher than 0.8. The test-retest reliability was good (intra-class correlation coefficient, 0.716; 95% confidence interval [CI], 0.100–0.935). An increase in the FAQL-PB was significantly associated with an increase in the FAIM-PF (β = 0.765, P < 0.001) (concurrent validity). There was a positive correlation between parental burden, anxiety, and depression, while resilience was inversely correlated with parental burden (all P < 0.001). The total FAQL-PB score in parents of children who had experienced anaphylaxis was significantly higher than that in parents of children who did not experience it (P = 0.008). When adjusting for age, sex, and underlying diseases, anaphylaxis β = 9.32; 95% CI, 2.97 to 15.68), cow’s milk (CM) allergy (β = 8.24; 95% CI, 2.04 to 14.44), soybean allergy (β = 13.91; 95% CI, 1.62 to 26.20), higher anxiety (β = 1.05; 95% CI, 0.07 to 1.41), higher depression (β = 2.15; 95% CI, 1.61 to 2.69), and lower resilience (β = −0.42; 95% CI, −0.61 to −0.2) were significantly associated with greater parental burden in children with IgE-mediated FAs. @*Conclusion@#FAQL-PB is a reliable and valid tool for use in Korea. Anaphylaxis, CM or soybean allergies, more anxiety and depression symptoms, and lower resilience are associated with poorer QoL in parents of children with FAs.

A case of esophagitis and mediastinitis developed in an infant with an esophageal duplication cyst

An esophageal duplication cyst (EDC) is a congenital anomaly of the foregut. EDCs are often asymptomatic, so they are found incidentally on chest radiographs. In symptomatic patients, EDCs present with cough, dyspnea, vomiting, dysphagia, and chest pain. Potential complications of EDCs include perforation, obstruction, bleeding, and infection. The rarity of this condition may hinder timely diagnosis, which may lead to life-threatening complications. This article describes a case of esophagitis and mediastinitis developed in a 12-month-old infant with an EDC. We emphasize that although rare, EDCs should be considered in the differential diagnosis of non-specific respiratory signs such as cough, dyspnea, and stridor.

Clinical Characteristics of Atopic Dermatitis in Korean School-Aged Children and Adolescents According to Onset Age and Severity

Background@#Atopic dermatitis (AD) is a heterogeneous disease with different age of onset, disease course, clinical symptoms, severity, and risk of comorbidity. The characteristics of children with AD also vary by age or country. However, little is known about the clinical characteristics of AD in Korean school-aged children and adolescents. Furthermore, there are few studies on phenotypic differences according to onset age. This study aimed to explore the clinical characteristics and phenotypes according to onset age and severity of AD in children and adolescents in Korea. @*Methods@#AD patients aged 6–18 years who presented to 18 hospitals nationwide were surveyed.The patients were examined for disease severity by pediatric allergy specialists, and data on history of other allergic diseases, familial allergy history, onset age, trigger factors, lesion sites,treatment history and quality of life were collected. The results of the patient’s allergy test were also analyzed. The patients were classified into infancy-onset (< 2 years of age), preschoolonset (2–5 years of age), and childhood-onset (≥ 6 years of age) groups. Study population was analyzed for clinical features according to onset-age groups and severity groups. @*Results@#A total of 258 patients with a mean age of 10.62 ± 3.18 years were included in the study. Infancy-onset group accounted for about 60% of all patients and presented significantly more other allergic diseases, such as allergic rhinitis and asthma (P = 0.002 and P = 0.001, respectively). Food allergy symptoms and diagnoses were highly relevant to both earlier onset and more severe group. Inhalant allergen sensitization was significantly associated with both infancy-onset group and severe group (P = 0.012 and P = 0.024, respectively). A family history of food allergies was significantly associated with infancyonset group (P = 0.036). Severe group was significantly associated with a family history of AD, especially a paternal history of AD (P = 0.048 and P = 0.004, respectively). Facial (periorbital, ear, and cheek) lesions, periauricular fissures, hand/foot eczema, and xerosis were associated with infancy-onset group. The earlier the onset of AD, the poorer the quality of life (P = 0.038). Systemic immunosuppressants were used in only 9.6% of the patients in the severe group. @*Conclusion@#This study analyzed the clinical features of AD in Korean children and adolescents through a multicenter nationwide study and demonstrated the phenotypic differences according to onset age and severity. Considering the findings that the early-onset group is more severe and accompanied by more systemic allergic diseases, early management should be emphasized in young children and infants.

Intravenous cidofovir as an adjuvant therapy for recurrent upper airway papillomatosis with lung involvement in a child

Recurrent respiratory papillomatosis (RRP) is a chronic disease related to human papillomavirus infection. The standard treatment of RRP is surgical resection of the lesion, but due to frequent recurrence, a combination of various adjuvant therapies has been attempted. Herein, we present the first case of RRP to whom intravenous cidofovir was administered as an adjuvant therapy in Korea. A 9-year-old boy was admitted due to hoarseness, stridor and breathing difficulty. At 10 months of age, he was diagnosed with RRP in the upper airway and thereafter he had repeatedly undergone surgical removal. During this hospitalization, papilloma was found again from the superior glottis to the inferior glottis and surrounding the trachea at the age of 9 years. In addition, well-defined nodular lesions were newly found on both lung fields, and a pathologic examination revealed a squamous papilloma with highgrade dysplasia, human papilloma virus types 6, 11, and 40 (low-risk type). Because of the frequent recurrence of papilloma in the upper airway as well as lung involvement, he underwent 38 injections of intravenous cidofovir for 2 years. During treatment, the intervals required for surgical removal of the mass causing upper airway obstruction were prolonged from an average of 37.3 to 74.6 days without serious side effects. However, intravenous cidofovir treatment had no effect on the lung lesion. This case shows that an intravenous cidofovir administration can be used as an adjuvant therapy in a child with RRP to relieve the upper airway obstruction, although this treatment does not cure the disease.

A case of food-induced acute pancreatitis in a child with egg white allergy

Acute pancreatitis (AP) rarely occurs in association with food allergy (FA), and the mechanism is not clearly explored. We herein report a rare case of egg protein-induced AP. A 5-year-old girl was brought to the hospital because of tongue pruritus and an increased level of egg white-specific immunoglobulin E. During an oral food challenge, she developed hives, abdominal pain and vomiting after ingestion of a cumulative of 610 mg of boiled egg white (70 mg of protein). After management with intramuscular injection of epinephrine and orally administered prednisolone and levocetirizine, her skin symptoms improved. The next day, blood tests showed elevated levels of amylase and lipase, and computed tomography revealed a swollen pancreas with a low-attenuated necrotic portion. She was diagnosed with AP and treated with food restriction, intravenous methylprednisolone and gabexate mesilate. The serum levels of amylase and lipase were reduced to normal levels on day 5 and her symptoms completely resolved on day 10. A suspicion of food-induced AP is required for correct diagnosis and proper management in children with FA when they manifest severe abdominal pain.

A case of ROHHAD (rapid-onset obesity with hypothalamic dysregulation, hypoventilation, and autonomic dysregulation) syndrome in an 11-year-old girl

Rapid-onset obesity with hypoventilation, hypothalamic, and autonomic dysregulation (ROHHAD) syndrome is a rare disease characterized by rapid progression of obesity and central hypoventilation with autonomic and endocrine dysregulation. There is no gold-standard diagnostic method for ROHHAD syndrome; it is diagnosed based on a years-long clinical course. For this reason, diagnosis of ROHHAD syndrome is often delayed. In particular, ROHHAD has a high mortality rate due to cardiopulmonary arrest when quick diagnosis and appropriate intervention of central sleep apnea are not timely. We report a case in which an 11-year-old girl with central sleep apnea was diagnosed with ROHHAD syndrome: the clinical course with early breathing intervention using noninvasive positive pressure ventilation. We emphasize the importance of respiratory interventions in the clinical course of ROHHAD syndrome.

Flow Cytometry for the Diagnosis of Primary Immunodeficiency Diseases: A Single Center Experience

PURPOSE: While there is an urgent need for diagnosis and therapeutic intervention in patients with primary immunodeficiency diseases (PIDs), current genetic tests have drawbacks. We retrospectively reviewed the usefulness of flow cytometry (FCM) as a quick tool for immunophenotyping and functional assays in patients suspected to have PIDs at a single tertiary care institute.METHODS: Between January 2001 and June 2018, patients suspected of having PIDs were subjected to FCM tests, including lymphocyte subset analysis, detection of surface- or intracellular-target proteins, and functional analysis of immune cells, at Samsung Medical Center, Seoul, Korea. The genetic diagnosis was performed using Sanger or diagnostic exome sequencing.RESULTS: Of 60 patients diagnosed with definite or probable PID according to the European Society of Immune Deficiencies criteria, 24 patients were provided with useful information about immunological dysfunction after initial FCM testing. In 10 patients, the PID diagnosis was based on abnormal findings in FCM testing without genetic tests. The FCM findings provided strong evidence for the diagnosis of severe combined immunodeficiency (n = 6), X-linked chronic granulomatous diseases (CGD) (n = 6), leukocyte adhesion deficiency type 1 (n = 3), X-linked agammaglobulinemia (n = 11), autoimmune lymphoproliferative syndrome-FASLG (n = 1), and familial hemophagocytic lymphohistiocytosis type 2 (n = 1), and probable evidence for autosomal recessive-CGD (n = 2), autosomal dominant-hyper-immunoglobulin E (IgE)-syndrome (n = 1), and STAT1 gain-of-function mutation (n = 1). In PIDs derived from PIK3CD (n = 2), LRBA (n = 2), and CTLA4 mutations (n = 3), the FCM test provided useful evidence of immune abnormalities and a tool for treatment monitoring.CONCLUSIONS: The initial application of FCM, particularly with known protein targets on immune cells, would facilitate the timely diagnosis of PIDs and thus would support clinical decisions and improve the clinical outcome.

Imbalance of Gut Streptococcus, Clostridium, and Akkermansia Determines the Natural Course of Atopic Dermatitis in Infant

PURPOSE: The roles of gut microbiota on the natural course of atopic dermatitis (AD) are not yet fully understood. We investigated whether the composition and function of gut microbiota and short-chain fatty acids (SCFAs) at 6 months of age could affect the natural course of AD up to 24 months in early childhood.METHODS: Fecal samples from 132 infants were analyzed using pyrosequencing, including 84 healthy controls, 22 transient AD and 26 persistent AD subjects from the Cohort for Childhood Origin of Asthma and Allergic Diseases (COCOA) birth cohort. The functional profile of the gut microbiome was analyzed by whole-metagenome sequencing. SCFAs were measured using gas chromatography-mass spectrometry.RESULTS: Low levels of Streptococcus and high amounts of Akkermansia were evident in transient AD cases, and low Clostridium, Akkermansia and high Streptococcus were found in children with persistent AD. The relative abundance of Streptococcus positively correlated with scoring of AD (SCORAD) score, whereas that of Clostridium negatively correlated with SCORAD score. The persistent AD group showed decreased gut microbial functional genes related to oxidative phosphorylation compared with healthy controls. Butyrate and valerate levels were lower in transient AD infants compared with healthy and persistent AD infants.CONCLUSIONS: Compositions, functions and metabolites of the early gut microbiome are related to natural courses of AD in infants.

Three cases of oral immunotherapy for IgE-mediated egg allergy

Food allergy is an immune-mediated adverse reaction that occurs mainly by food ingestion. Some children with food allergies manifest fatal symptoms like anaphylaxis. Oral immunotherapy (OIT) may offer an effective therapeutic modality for persistent and severe forms of food allergies. We report our experience with OIT in 3 patients with IgE-mediated hen’s egg allergy. Our treatment strategy consists of 1–3 days of initial escalation, 47 to 65 weeks of build-up phase, and 1 year of maintenance phase. Lactobacillus plantarum CJLP133, 1×1010 colony-forming unit/day was taken during OIT. As a result, 1 patient achieved successful desensitization, and 1 patient reached maintenance therapy, but did not obtain desensitization. In addition, 1 patient withdrew from treatment due to anxiety symptoms. Despite the limited number of patients, we experienced and herein presented 3 cases of OIT in egg allergy. More trials of OIT need to be performed as a treatment option in Korean children with food allergies.

The current status and issue of food allergen labeling in Korea

With increasing need to prevent serious food allergy reactions, Korean food allergen labeling regulation has been revised repeatedly. This paper aims to summarize current statuses of food allergen labeling in Korea and foreign countries and to analyze the issue of food allergen labeling regulation. Korean food labeling regulation currently requires 19 items and 22 foods to be reported on labels (eggs, milk, buckwheat, peanut, soybean, wheat, mackerel, crab, shrimp, pork, peach, tomato, sulfite, walnut, chicken, beef, squid, shellfish, and pine nut). However, some common food triggers (for example, almond, cashew nut, and kiwi fruit) are not included in the current labeling regulation. Another issue is that the Korean labeling regulation has not yet been fully implemented for nonprepacked foods; thus, consumers still have difficulty in correctly identifying allergenic ingredients in food. It should be assessed whether warning statements for cross-contamination are reasonable. To prevent the occurrence of serious reactions from accidental ingestion, efforts must be made to solve recently raised issues including the items required to be listed on food labels, the system of standards for labeling and display methods.

A case of FLNA gene mutation with respiratory insufficiency and periventricular heterotopia

Filamin A is an actin-binding protein and, in humans, is encoded by FLNA gene in the long arm of X chromosome. Filamin A plays a role in the formation of cytoskeleton by crosslinking actin filaments in cytoplasm. FLNA mutations affect cytoskeletal regulatory processes and cellular migrating abnormalities that result in periventricular heterotopia. A 5-month-old girl was hospitalized because of breathing difficulty and was diagnosed as having periventricular heterotopia with laryngomalacia, cricopharyngeal incoordination, pulmonary hypertension, and chronic lung disease. A genetic test was performed to find the cause of periventricular heterotopia, and FLNA gene mutation (c.5998+1G>A) was confirmed for the first time in Korea. After discharge, she developed respiratory failure due to a viral infection at 8 months of her age. In spite of management with mechanical ventilation, she died of pneumothorax and pulmonary hemorrhage. Herein, we report a case of FLNA gene mutation who presented with periventricular nodular heterotopia with respiratory insufficiency.

Interactions Between Atopic Dermatitis and Staphylococcus aureus Infection: Clinical Implications

Staphylococcus aureus commonly colonizes the skin of atopic dermatitis (AD) patients and contributes to the development and exacerbation of AD. Multiple factors are associated with colonization of AD skin by S. aureus, including the strength of S. aureus-corneocyte adhesion, deficiency of antimicrobial peptides, decreased levels of filaggrin and filaggrin degradation products, overexpressed Th2/Th17 cytokines, microbial dysbiosis and altered lipid profiles. S. aureus colonization on AD skin causes skin barrier dysfunction through virulence factors such as superantigens (toxins), enzymes and other proteins. Furthermore, colonization of AD skin by S. aureus exacerbates AD and may contribute to microbial dysbiosis, allergen sensitization, Th2/Th17 polarization, development of atopic march and food allergy in AD patients. Skin colonization of S. aureus, particularly methicillin-resistant S. aureus (MRSA), is one of the major challenges commonly encountered in the management of AD. Bleach bath, and topical or systemic antibiotics could be used to control S. aureus infection on AD skin. However, careful use of antibiotics is required to control the occurence of MRSA. Recently, various strategies, including microbiome transplant, monoclonal antibodies against virulent toxins, vaccines and recombinant phage endolysin, have been studied to control S. aureus infection on AD skin. Further advances in our understanding of S. aureus could provide us with ways to manage S. aureus colonization more effectively in AD patients.

Prenatal Exposure to Lead and Chromium is Associated with IL-13 Levels in Umbilical Cord Blood and Severity of Atopic Dermatitis: COCOA Study

There have been few studies investigating the association between atopic dermatitis (AD) and prenatal exposure to heavy metals. We aimed to evaluate whether prenatal exposure to heavy metals is associated with the development or severity of AD in a birth cohort study. A total of 331 subjects were followed from birth for a median duration of 60.0 months. The presence and severity of AD were evaluated at ages 6 and 12 months, and regularly once a year thereafter. The concentrations of lead, mercury, chromium, and cadmium in umbilical cord blood were measured by inductively coupled plasma mass spectrometry. Cord blood mononuclear cells (CBMCs) were isolated and stimulated for analysis of cytokine production using ELISA. Heavy metal levels in cord blood were not associated with the development of AD until 24 months of age. However, a positive correlation was observed between the duration of AD and lead levels in cord blood (p=0.002). AD severity was also positively associated with chromium concentrations in cord blood (p=0.037), while cord blood levels of lead, mercury, and cadmium were not significantly associated with AD severity (p=0.562, p=0.054, and p=0.055, respectively). Interleukin-13 production in CBMCs was positively related with lead and chromium levels in cord blood (p=0.021 and p=0.015, respectively). Prenatal exposure to lead and chromium is associated with the persistence and severity of AD, and the immune reaction toward a Th2 polarization.

The risk of preschool asthma at 2–4 years is not associated with leukocyte telomere length at birth or at 1 year of age

BACKGROUND: Exposure to prenatal stress is associated with offspring allergic-disease development, and oxidative stress may mediate this relationship. OBJECTIVE: We aimed to evaluate whether leukocyte telomere length (LTL) shortening, a marker for exposure to oxidative stress, in early life is associated with increased risk of asthma development during the preschool period. METHODS: We assessed the follow-up clinical data of a subgroup from a birth cohort whose LTLs had been measured from cord-blood and 1-year peripheral-blood samples. We examined whether the LTLs would be associated with asthma development at the age of 2–4 years. RESULTS: The data of 84 subjects were analyzed. LTLs were measured from the cord-blood and 1-year peripheral blood of 75 and 79 subjects, respectively. Among them, 14 subjects (16.7%) developed bronchial asthma between 2–4 years old. Prenatally stressed subjects had marginally increased odds of developing asthma (p = 0.097). There was no significant difference in the odds of preschool-asthma development between the groups with shorter and longer cord-blood LTLs (odds ratio [OR], 0.651; 95% confidence interval [CI], 0.184–2.306) or in the odds between the groups with shorter and longer 1-year peripheral-blood LTLs (OR, 0.448; 95% CI, 0.135–1.483). Finally, subjects with both higher prenatal stress and shorter LTLs did not have significantly higher odds of preschool-asthma development (for cord-blood: OR, 1.242; 95% CI, 0.353–4.368; for 1-year peripheral-blood: OR, 1.451; 95% CI, 0.428–4.919). CONCLUSION: There was no significant association between early life LTLs and higher risk of bronchial-asthma development during the preschool years.

Infantile Anaphylaxis in Korea: a Multicenter Retrospective Case Study

BACKGROUND: Anaphylaxis is increasing in young children. The aim of the present study was to analyze the clinical characteristics of anaphylaxis in Korean infants, with a focus on food triggers. METHODS: The study analyzed the medical records of infants aged 0 to 2 years old who had been diagnosed with anaphylaxis in 23 secondary or tertiary hospitals in Korea. RESULTS: We identified 363 cases of infantile anaphylaxis (66.9% male). Cutaneous symptoms were most prevalent (98.6%), followed by respiratory (83.2%), gastrointestinal (29.8%), and neurologic (11.6%) symptoms. Cardiovascular symptoms were noted in 7.7% of the cases. Most of the cases of anaphylaxis (338; 93.1%) were induced by foods. The most common trigger food was cow's milk and cow's milk products (43.8%), followed by hen's eggs (21.9%), walnuts (8.3%), wheat (7.7%), peanuts (4.8%), other nuts (3.0%), and fish (2.1%). In cow's milk-induced anaphylaxis cases, more than half the cases had cow's milk specific immunoglobulin E (sIgE) levels that were lower than the diagnostic decision points (DDPs), which is 5 kUA/L for those under the age of 1 and 15 kUA/L for those over the age of 1. In anaphylaxis induced by hen's egg, most of the cases (91.8%) had hen's egg sIgE levels that were higher than the DDP, which is 2 kUA/L for those under the age of 2 and 7 kUA/L for those over the age of 2. Of the infantile anaphylaxis cases, 46.8% had been treated with epinephrine, and 25.1% had been prescribed an epinephrine auto-injector. CONCLUSION: Cow's milk is the most frequent trigger food of anaphylaxis in Korean infants. However, we found no significant correlation between the sIgE level and clinical severity. Education is required regarding the importance of epinephrine as the first line therapy for anaphylaxis and on properly prescribing epinephrine for infants with a history of anaphylaxis.

Leukocyte Telomere Length Reflects Prenatal Stress Exposure, But Does Not Predict Atopic Dermatitis Development at 1 Year

PURPOSE: Prenatal maternal stress affects offspring's atopic dermatitis (AD) development, which is thought to be mediated by the oxidative stress. We aimed to evaluate the difference in leukocyte telomere length (LTL), a marker for exposure to oxidative stress, according to the prenatal stress exposure and the later AD development. METHODS: From a birth cohort (the COhort for Childhood Origin of Asthma and allergic diseases) that had displayed a good epidemiologic association between the exposure to prenatal stress and AD development in the offspring, we selected 68 pairs of samples from 4 subject groups based on the level of prenatal maternal stress and later AD development. The LTL was measured from both cord blood and 1-year peripheral blood, and their LTLs were compared between subject groups. Finally, the proportion of AD development was examined in the subject groups that are reclassified based on subjects' exposure to prenatal stress and there LTL. RESULTS: Cord-blood LTL was shorter in prenatally stressed infants than in unstressed ones (P = 0.026), which difference was still significant when subjects became 1 year old (P = 0.008). LTL of cord blood, as well as one of the 1-year peripheral blood, was not different according to later AD development at 1 year (P = 0.915 and 0.174, respectively). Shorter LTL made no increase in the proportion of later AD development in either prenatally high-stressed or low-stressed groups (P = 1.000 and 0.473, respectively). CONCLUSIONS: Cord-blood LTL may reflect subjects' exposure to maternal prenatal stress. However, the LTL shortening is not a risk factor of increasing AD development until the age of 1, and a longer investigation may be necessary for validation. Currently, the results doubt the role of LTL shortening as a marker for risk assessment tool for the prenatal stress associated with AD development in the offspring.

Epidemiology of food allergy in Korean children

Food allergy has emerged as an important public health problem affecting people of all ages in many countries. The prevalence varies according to age, geographic regions, and ethnicity. For several years, many studies have suggested that the prevalence of food allergy is increasing at an alarming rate, for unclear reasons. Conversely, some studies have also provided findings that sensitization to common food allergens did not increase. Increased recognition rather than an actual increase in patients with IgE-mediated food allergy might lead to the increases in the prevalence of self-reported or physician-diagnosed food allergy. It is also noted that the prevalence of food allergy differs even in the same region according to the study design, i.e., hospital-based or community-based studies. Despite these limitations, epidemiologic data are important because they provide useful information on diagnosis, treatment, and prevention of food allergy. This review focuses on advances in the epidemiology of food allergy in Korean children.

The past, present, and future of the research on food allergy in Korean children

Food allergy is an immune-mediated adverse reaction that occurs mainly by consumption of food. Some of the children with food allergies have mild symptoms like urticaria and pruritus, while others manifest fatal symptoms like anaphylaxis. Many cases develop in infants and children, and disappear spontaneously over time. The prevalence of food allergy is known to be up to 6% of children and 3%–4% of adults. Growing concern is that prevalence of food allergy seems to be increasing. The prevalence, common allergens and natural course of food allergy vary according to the race, age, eating habits, and unknown factors. In Korea, many researchers have reported regional data on food allergy for comparison with those of foreign countries. Awareness is increasing and food labelling is being established to help people avoid allergenic foods. In the future, monitoring of prevalence and common food allergens at regular intervals is needed to make appropriate policies for children with food allergy. There are still lack of data on pathogenesis, natural course and clinical trials of immunotherapy in Korean children. In addition, it is necessary to form a consensus on primary prevention of food allergy by early exposure to allergenic foods. Further regional studies should be performed to expand our understanding of food allergy and to lead to proper management for Korean children with food allergy.

Perception of food allergy among parents and school health instructors: A nationwide survey in 2015

PURPOSE: This study aimed to examine the perception of food allergy among parents and school health instructors in Korea. METHODS: A nationwide epidemiological survey in Korea was conducted in September 2015. From 17 cities and provinces, a total of 1,000 elementary, middle and high schools were selected by stratified random sampling. Parents and school health instructors were surveyed using a questionnaire on the perception of food allergy. RESULTS: The prevalence of food-induced anaphylaxis was 22.3%. Of 252 children with anaphylaxis, 47.6% were prescribed epinephrine auto-injector (EAI). Forty-three parents (37.7%) were educated about the use of EAI. Parents carrying their own EAI at all times or keeping them at schools were 5.6% and 3.8%, respectively. For the food allergen-labeling system, 42.1% of parents read food labels, and 32.1% were satisfied with the system. Only 35.2% of school health instructors received education on food allergy and anaphylaxis, and 42.5% of them knew how to use EAI. There were 70 children (9.4%) with anaphylaxis in school, and 75.9% of schools had the emergency management system. CONCLUSION: The awareness of Korean parents and school health instructors on food allergy is still low, and many parents are dissatisfied with the food allergen labeling system. Many school health instructors have difficulty in using EAI in case of anaphylaxis and are insufficiently educated about food allergy. Therefore, it is necessary to establish more systematic food allergy management plans by providing high-quality education to parents and school health instructors and by utilizing legal systems.

Prevalence of Immediate-Type Food Allergy in Korean Schoolchildren in 2015: A Nationwide, Population-based Study

PURPOSE: This study aimed to determine the prevalence of immediate-type food allergy (FA) among schoolchildren in Korea. METHODS: A nationwide, cross-sectional study was performed in September 2015. A stratified random sample of 50,000 participants was selected from children and adolescents aged 6-7 years (n=17,500), 9-10 years (n=17,500), 12-13 years (n=7,500), and 15-16 years (n=7,500). Parents were asked to complete a questionnaire on the detailed history of immediate-type FA. RESULTS: A total of 32,001 (64.0%) responded to the questionnaire survey, and 29,842 children (59.7%) were analyzed after adjusting for missing data. The number of the cases in each age group was 9,671 (6-7 years), 9,756 (9-10 years), 5,169 (12-13 years), and 5,246 (15-16 years). The prevalence of lifetime perceived FA was 15.82%. The prevalence of current immediate-type FA was 4.06% in total, with 3.15% in 6- to 7-year-olds, 4.51% in 9- to 10-year-olds, 4.01% in 12- to 13-year-olds, and 4.49% in 15- to 16-year-olds. Among individual food items, peanut (0.22%) was the most frequent causative food, followed by hen's egg (0.21%), cow's milk (0.18%), and buckwheat (0.13%). Among the food groups, fruits (1.41%), crustaceans (0.84%), tree nuts (0.32%), and fish (0.32%) were the most common offending foods. The prevalence of food-induced anaphylaxis was 0.97%. The most frequent causative food of anaphylaxis was peanut (0.08%), followed by cow's milk (0.07%), buckwheat (0.06%), and hen's egg (0.06%), while fruits (0.28%), crustaceans (0.18%), tree nuts (0.12%), and fish (0.09%) were the most commonly responsible food groups. CONCLUSIONS: The prevalence of current immediate-type FA and food-induced anaphylaxis in Korean schoolchildren in 2015 was 4.06% and 0.97%, respectively. Peanuts, cow's milk, hen's egg, fruits, crustaceans, and tree nuts are common allergens.