Seasonal and monthly variation in peak expiratory flow rate in children with asthma.

BACKGROUND: Although understanding the seasonal patterns of asthma deterioration is important to prevent asthma exacerbation, previous approaches have limitations in evaluating the actual trend of asthma exacerbation. OBJECTIVE: This study aimed to evaluate the seasonal and monthly variations in the peak expiratory flow rate (PEFR) among children with asthma. METHODS: A total of 89 patients with asthma were enrolled between December 2012 and March 2015. The PEFR in the morning and evening was recorded daily, and the percentage change in PEFR from baseline was calculated. Generalized estimating equation models were constructed after adjusting for age, sex, body mass index, and sensitization to house dust mites or pollen. RESULTS: The PEFR records of 11,222 person-days showed a significant decrease in the morning and evening in autumn than in winter by -1.9% (95% confidence interval [CI], -3.73 to -0.15) and -2.1% (95% CI, -3.80 to -0.37), respectively. The morning PEFR was significantly lower in April, August, October, and December than in January with changes of -4.2% (95% CI, -7.08 to -1.23) in April, -3.1% (95% CI, -5.79 to -0.47) in August, -3.7% (95% CI, -6.09 to -1.21) in October, and -1.9% (95% CI, -3.62 to -0.12) in December. The percentage change of evening PEFR significantly decreased by -3.3% (95% CI, -6.38 to -0.25) in April and by -3.3% (95% CI, -5.56 to -1.07) in October. CONCLUSION: The PEFR in children with asthma was lower in autumn than in winter. In terms of monthly patterns, the PEFR was significantly reduced in April and October than in January. These results can serve as a basis for preventing asthma exacerbations by developing seasonal or monthly management strategies for children with asthma.

The Natural Course of Immediate-Type Cow's Milk and Egg Allergies in Children.

BACKGROUND: Most of children with cow's milk (CM) and hen's egg allergies are known to outgrow their diseases with time, but recent studies have demonstrated that children tend to continue to have allergic symptoms in adolescence and adulthood. The aim of this study was to investigate the natural course of CM and egg allergies in Korean children and analyze prognostic factors. METHODS: In this retrospective study, we reviewed data of children with CM allergy and with egg allergy using medical records and parental telephone interviews. Diagnosis of CM or egg allergy was based on positive oral food challenge test or convincing history of allergic symptoms in combination with positive allergen-specific IgE. Acquisition of tolerance was defined by the absence of allergic symptoms after reintroduction of the offending foods. RESULTS: Half of the children outgrew CM allergy at a median age of 8.7 years. CM-specific IgE level at the first reaction was a significant prognostic factor for oral tolerance in CM allergy (p < 0.05). The median age to acquire oral tolerance in 50% of patients with egg allergy was 5.6 years. Egg-specific IgE level at the first reaction and family history of allergic diseases significantly affected the prognosis in children with egg allergy (p < 0.05). CONCLUSIONS: Half of Korean children with CM and egg allergies had symptom resolution at 8.7 and 5.6 years of age, respectively. Our results also suggest that CM- and egg-specific IgE levels at the first reaction are the most significant prognostic factors in predicting acquisition of oral tolerance.

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.

Seasonal variation and monthly patterns of skin symptoms in Korean children with atopic eczema/dermatitis syndrome.

BACKGROUND: There have been controversies about the seasonality in aggravation of atopic eczema/dermatitis syndrome (AEDS) symptoms, although understanding the seasonal patterns of AEDS symptoms is an important step in preventing exacerbation through proactive management. OBJECTIVE: The aim of this study was to evaluate whether there are seasonal variations or monthly patterns of symptoms in children with AEDS. METHODS: A total of 590 children with AEDS (median age, 21 months) were enrolled and were followed up for at least 1 year between August 2012 and March 2015. Daily symptom scores that described the extent of itching, sleep disturbance, erythema, dryness, oozing, and edema were recorded on a scale of 0 to 4. The baseline score for each patient was defined as the 20th percentile of each individual's total score. The symptom score difference of each patient was expressed relative to the baseline level. The seasonal or monthly variation in symptom score differences was analyzed through generalized estimating equation analysis. RESULTS: Based on the AEDS symptom records from 87,879 person-days, the mean symptom score difference from baseline in patients with AEDS increased significantly in spring, autumn, and winter relative to the reference season (summer): by 0.62 (95% confidence interval [CI], 0.44-0.81) in spring, by 0.45 (95% CI, 0.24-0.67) in winter, and by 0.18 (95% CI, 0.02-0.36) in autumn. The mean symptom score difference from baseline increased significantly in January, February, March, April, May, June, October, November, and December relative to the reference month of August. CONCLUSION: Skin symptoms in children with AEDS were worse in spring, winter, and autumn than in summer. In terms of monthly patterns, the skin symptoms were the worst in April.

Is the prevalence of atopic dermatitis in Korean children decreasing? : National Database 2009-2014.

BACKGROUND: The prevalence of atopic dermatitis (AD) in children is increasing in many developing countries. OBJECTIVE: This study aimed to explore trends in the prevalence of AD in Korean children. METHODS: We analyzed data from the Korean National Health Insurance Service (NHIS) from 2009 to 2014. Data for the estimated populations were collected from the Statistics Korea. The annual prevalence of AD was obtained by dividing the number of patients by the estimated population each year. We analyzed the prevalence of AD in 2014 and evaluated the change in the annual prevalence of AD from 2009 through 2014. RESULTS: The estimated population of children aged 18 years or younger was 9,992,581 in 2014, and the number of children with AD was 578,678 with the prevalence of 5.8%. The prevalence was 17.2% in infants aged 12-23 months, which decreased substantially to 7.3%, 3.2% and 2.4% at 5, 12 and 18 years of age, respectively. In the pediatric age group, the prevalence of AD slightly decreased from 6.5% to 5.8% from 2009 through 2014. Notably, in infants aged less than 24 months, the prevalence decreased from 20.8% to 15.4%. CONCLUSIONS: Based on the Korean NHIS database, the prevalence of AD in Korean children aged 18 years or younger appears to be decreasing, especially in infants. Although the reason is not clear, an increase in breast milk feeding, vaginal delivery or consumption of probiotics might be involved. Further studies are needed to confirm this trend and to explain the possible mechanisms.

The association between hypovitaminosis D and pediatric allergic diseases: A Korean nationwide population-based study.

BACKGROUND: There is still considerable disagreement regarding the role of vitamin D in the development or exacerbation of allergic diseases. OBJECTIVE: To investigate the association between serum vitamin D levels and recent symptoms of allergic diseases in elementary schoolchildren. METHODS: A nationwide cross-sectional survey was conducted in children ages 6-7 years from 45 randomly selected elementary schools. The presence of atopic dermatitis (AD) or asthma was defined as medical treatment of children for AD or asthma within 12 months of the survey. The presence of allergic rhinitis (AR) was defined as medical treatment for AR during the past 12 months and a positive skin test response. Current AD was defined as confirmed eczema on physical examination. Serum 25-hydroxyvitamin D (25[OH]D) was measured by chemiluminescent immunoassay. RESULTS: Questionnaire data and blood samples were collected from 3720 children. The overall prevalence rates of vitamin D insufficiency (20-29 ng/mL) and deficiency (<20 ng/mL) were 64.0% and 18.4%, respectively. For a 1 ng/mL decrease in 25(OH)D, the adjusted odds ratio (aOR) for AR was 1.020 (95% confidence interval [CI], 1.002-1.040) and the aOR for current AD was 1.027 (95% CI, 1.006-1.047). For each 1 ng/mL decrease in 25(OH)D, the aOR for positive skin-prick test reactivity was 1.013 (95% CI, 1.000-1.027). No significant association between vitamin D level and the prevalence of asthma was observed. CONCLUSIONS: A high prevalence of vitamin D deficiency and insufficiency was found in Korean elementary schoolchildren, and low vitamin D levels were associated with recent symptoms of AD and AR.

Fundoplication in neonates and infants with primary gastroesophageal reflux.

PURPOSE: Gastroesophageal reflux in infant is a physiological process. However, surgery is performed in high risk infants with severe gastroesophageal reflux disease (GERD) when medical management fails. This study focuses on efficacy and safety of Nissen fundoplication for GERD in infants under age 12 months. METHODS: This study was a retrospective case analysis of 11 neonates and infants under 12 months of age who underwent Nissen fundoplication following a failure of medical treatment between June 2010 and June 2013 at Pusan National University Children's Hospital. The records were reviewed to determine the effect of fundoplication on symptoms and post-operative complications. RESULTS: A total of 11 infants consist of four males and seven females. Mean birth weight was 2,305.5±558.6 g (1,390-3,130 g). They had some underlying disease, which are not related with GERD such as congenital heart disease (54.5%), prematurity (45.5%), neurologic disease (18.2%), respiratory disease (18.2%), and other gastrointestinal disease. Mean body weight at surgery was 3,803.6±1,864.9 g (1,938.7-5,668.5 g). Mean age at operation was 99.9±107.6 days (17-276 days). Duration from operation to full enteral feeding was 10.9 days. Symptoms related GERD disappeared in all patients including one who got reoperation. One infant died of congenital heart disease unrelated to surgery. There were no complications related to fundoplication. CONCLUSION: Fundoplication is effective and safe treatment in the neonates and infants with severe GERD.

Ibuprofen associated acute vanishing bile duct syndrome and toxic epidermal necrolysis in an infant.

Acute vanishing bile duct syndrome, a rare but rapidly progressive destruction of the intrahepatic bile ducts with unknown pathogenesis, is most often a drug- or toxin-related. Toxic epidermal necrolysis is a serious dermatologic condition and a potentially life threatening disease, which is drug or infection induced. Ibuprofen associated acute vanishing bile duct syndrome and toxic epidermal necrolysis have not been reported previously in infants. We report a 7-month-old infant with ibuprofen associated toxic epidermal necrolysis, followed by severe and rapidly progressive vanishing bile duct syndrome. She recovered totally with supportive care.