Anaphylaxis in children: Effect of age and atopic status.

BACKGROUND: Anaphylaxis is a life-threatening allergic reaction with rising incidence worldwide. Young children's limited ability to express symptoms adds unique diagnostic challenges. OBJECTIVE: To study on anaphylaxis in children, including triggers, symptoms, treatment, atopic status impact, and adrenaline injection time intervals. METHODS: In-patient medical records of children who were diagnosed with anaphylaxis during 2014-2021 were reviewed. RESULTS: One hundred thirty-three anaphylaxis events were identified. Food (47%) was the most common trigger, followed by drugs (31%), blood components (17%), insects (3%), and idiopathic causes (2%). Ten cases of refractory anaphylaxis, 2 cases of biphasic reactions, and 1 case of persistent anaphylaxis were found. There were no reported fatalities. The most common presentations involved the skin (94%), followed by the respiratory (73%), gastrointestinal (47%), and cardiovascular (42%) systems. In atopic patients, wheezing was more prominent than in those without atopy (p-value = 0.017). In the non-atopic patients, there was a higher incidence of cardiovascular symptoms, particularly hypotension (p-value = 0.001), compared to individuals with atopy. Children under 5 years old with mild-moderate anaphylaxis required more time to reach the hospital (147.0 vs. 45.0 minutes, p = 0.033) and to receive adrenaline injections (35.0 vs. 9.0 minutes, p-value = 0.017) than those with severe anaphylaxis. CONCLUSION: Childhood anaphylaxis is prevalent. Children with mild-moderate anaphylaxis experienced delays in hospital visits and adrenaline administration. Education on allergies is needed to improve the identification and prompt response to anaphylactic reactions, especially in young children.

Skin prick test and serum specific IgE in predicting dust mite-induced allergic rhinitis diagnosed from nasal provocation test in chronic rhinitis children.

BACKGROUND: Allergen skin prick test (SPT) and serum specific immunoglobulin E (sIgE) are effective diagnostic tests in allergic rhinitis (AR), however, positive results may not always correlate with clinical allergies. A nasal provocation test (NPT) can identify the causative allergen for immunotherapy, but it's not routinely performed. OBJECTIVE: To establish the cutoff value for the house dust mite (HDM) SPT mean wheal diameter (MWD) and HDM sIgE level for identifying children with HDM-induced AR diagnosed from NPT. METHODS: Children aged 5 to 18 years old with chronic rhinitis were evaluated by HDM SPT, sIgE, and NPT. Children with positive NPT results indicated HDM-induced AR. The cutoff values of the HDM SPT and sIgE level for predicting positive NPT were determined using a receiver operating characteristic curve. RESULTS: A total of 245 children with a mean age of 9.53 ± 3 years were enrolled. HDM SPT results were positive (≥ 3 mm) in 160 (65.3%) children. HDM NPT results were positive in 176 (71.8%) children. Among children with positive HDM SPT (n = 160), 153 children (95.6%) were confirmed as having AR on NPT findings. The cutoff values for positive NPT responses were 6.6 mm for HDM SPT (yielding 100% specificity and 100% positive predictive value) and 17.0 kUA/L for sIgE (98.6% specificity and 99.2% positive predictive value). CONCLUSIONS: This study proposes HDM SPT and sIgE cutoff values for use in the diagnosis of HDM-induced AR based on NPT. These cutoff values can be used to identify HDM-induced AR children who might benefit from immunotherapy.

Benefits of mobile messenger application in caregivers of food allergy children.

BACKGROUND: Unintentional exposure is common in children with food allergies. OBJECTIVE: To assess the benefits of newly developed food allergy application. METHODS: Caregivers of children with confirmed immediate reactions to food were enrolled to use the "Kinchew" application for one month. Kinchew provides the detail of food allergens after typing the name of specific food in the chat box. Then, the app provides the product image and detail of food allergens. Kinchew also has a menu for recording food diaries and videos on managing food allergies. Kinchew users were asked to assess their confidence in dealing with food allergies assessed by the questionnaire using 5 points Likert scale. The number of patients who experienced allergic reactions from unintentional food exposure was recorded after using Kinchew. RESULTS: Seventy caregivers were enrolled. Wheat was the most common causative food in 67% of the participants. All participants used Kinchew with a total use of 1,754 times, classified as food items searching 1080 times (62%), and recorded their food diary 674 times (38%). The number of patients who experienced allergic reactions from unintentional exposure significantly decreased from 61 (87%) to 31 (44%), p < 0.001.The user's confidence in choosing food improved significantly compared to the baseline score. In the subgroup analysis of the type of causative food, a significant improvement in confidence in food choosing was demonstrated in wheat and multiple food allergy groups. CONCLUSIONS: Well-designed food allergy mobile applications could improve caregivers' confidence in dealing with food allergies and reduce unintentional food exposure.

Effect of dyslipidemia, obesity, and atopic status on exhaled and alveolar nitric oxide in asthmatic children.

BACKGROUND: Dyslipidemia and obesity contribute to a pro-inflammatory state. Eosinophilic airway inflammation can be indirectly measured by fractional exhaled nitric oxide (FeNO) produced in the airways of asthmatic subjects. OBJECTIVE: To compare exhaled nitric oxide (NO) and alveolar NO in asthmatic children with and without dyslipidemia. METHODS: Asthmatic children (5-18 years old) had fasting serum low-density lipoprotein cholesterol, triglyceride, and high-density lipoprotein cholesterol (HDL-C) concentrations, and C-reactive protein (CRP) concentrations measured. FeNO was measured at constant flow rates of 20, 50, 100, and 300 ml/s by the chemiluminescence method. NO concentrations in tissue of the upper airways (CawNO) and the total flux of NO in the conducting airways (JawNO) were determined through FeNO at 20, 100, and 300 ml/s using a mathematical model. The atopic status was assessed using the skin prick test for aero-allergens. RESULTS: One hundred forty-one asthmatic children were enrolled with a mean (standard deviation) age of 11.82 (3.38) years. Sixty-four (45.4%) children had dyslipidemia and 20 (14.2%) were obese. Children with low HDL-C concentrations had significantly higher CawNO and JawNO than those with normal HDL-C concentrations (both p = 0.03). Asthmatic children with obesity had higher CRP concentrations than those with a normal weight (p < 0.001). Atopic children had a significantly higher FeNO, CawNO, and JawNO than non-atopic children (all p < 0.05). CONCLUSIONS: This study suggests an effect of HDL-C on CawNO and JawNO in asthmatic children. An intervention that normalizes HDL-C concentrations may be beneficial for airway inflammation in asthmatic children.

Serum Periostin Predicts Wheezing Exacerbation: A Prospective Study in Preschool Children with Recurrent Wheezing.

INTRODUCTION: Wheezing is a common problem in preschool children. Currently, there are no reliable biomarkers that can predict subsequent wheezing in preschool children. This study aimed to compare serum periostin levels between preschool children with and without recurrent wheezing and investigate its utility for predicting acute wheezing exacerbation. METHODS: Children aged 2-5 years with recurrent wheezing and healthy control children were enrolled. They were evaluated for serum periostin level at enrollment and subsequently followed for wheezing episodes in a 1-year prospective study. RESULTS: A total of 122 children were enrolled. Children in the recurrent wheezing group (n = 80) had a greater median serum periostin level (1,122.32 pg/mL [<10-6,978.93]) than that of the healthy control group (n = 40) (<10 pg/mL [<10-2,116.69]), p value = 0.006. After 1-year follow-up, subjects who experienced subsequent wheezing exacerbation episodes had a greater median of periostin level (5,321 pg/mL) compared with those with no exacerbation (<10 pg/mL), p value = 0.014. ROC curve analysis revealed that the level of serum periostin >1,200 pg/mL, corresponding to 78.9% sensitivity and 64.6% specificity, with an AUC of 0.701, p value = 0.009, could be a predictor for acute wheezing exacerbation within 1 year. Besides, subjects with serum periostin >1,200 pg/mL had greater odds of subsequent wheezing episodes compared with those with lower levels of serum periostin (adjusted odds ratio 10.0, 95% confidence interval: 2.3-43.5). CONCLUSIONS: Preschool children with recurrent wheezing have a greater serum periostin level than healthy control. Serum periostin may be a valuable biomarker for predicting acute wheezing exacerbations in the following year.

Association of Dyslipidemia and Respiratory Resistance Assessed by the Forced Oscillation Technique in Asthmatic Children.

PURPOSE: This study aimed to evaluate the associations between dyslipidemia and pulmonary function parameters assessed by spirometry and the forced oscillation technique in asthmatic children. METHODS: Asthmatic children (5-18 years old) had fasting serum lipid profiles including low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) concentrations, and C-reactive protein (CRP) measured. Pulmonary function tests were assessed by spirometry and the forced oscillation technique (FOT). RESULTS: One hundred forty-one asthmatic children were enrolled with a mean (SD) age of 11.82 (3.38) years. Eighty-eight (62.4%) children were boys, 64 (45.4%) had dyslipidemia, and 20 (14.2%) were obese. Among the children with dyslipidemia, a high LDL-C concentration (65.6%) was the most common form of dyslipidemia, followed by high TC (57.8%), high TG (35.9%), and low HDL-C concentrations (15.6%). Multivariable analysis showed significant associations between HDL-C concentrations and respiratory resistance at 5 Hz (R5) and respiratory resistance at 20 Hz (R20), and TC concentrations were modestly associated with reactance at 5 Hz (X5), the frequency of resonance (Fres), and the area of reactance (ALX). Asthmatic children who had high LDL-C concentrations had a significantly higher expiratory phase R5, whole breath R20, and expiratory phase R20 than those in children with normal LDL-C concentrations. CONCLUSION: This study suggests an association of blood cholesterol, especially HDL-C and LDL-C, and respiratory resistance measured by the FOT, irrespective of the obesity status. An intervention for improving LDL-C and HDL-C concentrations may be beneficial on lung function parameters in asthmatic children. CLINICAL TRIAL REGISTRATION: TCTR20200305005; date of registration: 03-04-2020 (retrospectively registered).