Personal Exposure to Total VOC Is Associated With Symptoms of Atopic Dermatitis in Schoolchildren

Background@#The urinary levels of volatile organic compound (VOC) metabolites provide individual exposure levels compared to data obtained by measuring these compounds in ambient air. We aimed to investigate the association between personal urinary concentrations of VOC metabolites and symptoms of atopic dermatitis in schoolchildren. @*Methods@#Nine urinary VOC metabolites were analyzed from urine samples of 149 children. Diagnosis of atopic dermatitis was determined using standardized questionnaires. Pediatricians visited the schools and rated the severity of symptoms using the SCORing Atopic Dermatitis (SCORAD) in all children. @*Results@#Forty-five children (30.2%) had atopic dermatitis based on the International Study of Asthma and Allergies in Childhood (ISAAC) results and 35 children (23.8%) had symptoms of atopic dermatitis with positive SCORAD index values (defined as SCORAD ≥ 5). Children with benzylmercapturic acid detected in personal urines were associated with presence of atopic dermatitis and positive SCORAD index values. Children in the highest quartile of mandelic acid concentration were associated with presence of atopic dermatitis and positive SCORAD results. @*Conclusion@#Personal exposure to VOCs, as indicated by urinary levels of VOC metabolites, was associated with presence of atopic dermatitis and the SCORAD index value.

Risk factors and protective factors in pediatric patients with allergic rhinitis

Among allergic diseases of the Korean pediatric population, allergic rhinitis shows the most rapidly increasing prevalence. Its economic burden is substantial in many Asian countries including South Korea. This investigation of its risk factors aims to reduce the socioeconomic burden by blocking exposure of susceptible individuals to identified causes. However, the risk factors of allergic rhinitis varied considerably depending on the seasons, geographical locations, and populations involved. This review article primarily deals with studies on the risk factors for allergic rhinitis in Korean children that were published during the last 10 years and additionally investigates associated large scale international studies. Our investigation identified several single-nucleotide polymorphisms, inhalant allergens, pollution, tobacco smoke, chemicals, and family affluence as risk factors for allergic rhinitis. In contrast, breastfeeding, older sibling, and microbial diversity were protective factors against allergic rhinitis. This suggests that various genetic and environmental factors might affect the manifestation and presentation of allergic rhinitis complexly. These findings are beneficial as they can provide insights into modifiable risk factors that may hinder the development of allergic rhinitis.

Non-alcoholic Fatty Liver Disease and COVID-19 Susceptibility and Outcomes: a Korean Nationwide Cohort

Background@#Evidence for the association between underlying non-alcoholic fatty liver disease (NAFLD), the risk of testing severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) positive, and the clinical consequences of coronavirus disease 2019 (COVID-19) is controversial and scarce. We aimed to investigate the association between the presence of NAFLD and the risk of SARS-CoV-2 infectivity and COVID-19-related outcomes. @*Methods@#We used the population-based, nationwide cohort in South Korea linked with the general health examination records between January 1, 2018 and July 30, 2020. Data for 212,768 adults older than 20 years who underwent SARS-CoV-2 testing from January 1 to May 30, 2020, were obtained. The presence of NAFLDs was defined using three definitions, namely hepatic steatosis index (HSI), fatty liver index (FLI), and claims-based definition. The outcomes were SARS-CoV-2 test positive, COVID-19 severe illness, and related death. @*Results@#Among 74,244 adults who completed the general health examination, there were 2,251 (3.0%) who were SARS-CoV-2 positive, 438 (0.6%) with severe COVID-19 illness, and 45 (0.06%) COVID-19-related deaths. After exposure-driven propensity score matching, patients with pre-existing HSI-NAFLD, FLI-NAFLD, or claims-based NAFLD had an 11–23% increased risk of SARS-CoV-2 infection (HSI-NAFLD 95% confidence interval [CI], 1–28%; FLI-NAFLD 95% CI, 2–27%; and claims-based NAFLD 95% CI, 2–31%) and a 35–41% increased risk of severe COVID-19 illness (HSI-NAFLD 95% CI, 8–83%; FLI-NAFLD 95% CI, 5–71%; and claims-based NAFLD 95% CI, 1–92%). These associations are more evident as liver fibrosis advanced (based on the BARD scoring system). Similar patterns were observed in several sensitivity analyses including the full-unmatched cohort. @*Conclusion@#Patients with pre-existing NAFLDs have a higher likelihood of testing SARSCoV-2 positive and severe COVID-19 illness; this association was more evident in patients with NAFLD with advanced fibrosis. Our results suggest that extra attention should be given to the management of patients with NAFLD during the COVID-19 pandemic.

Main epidemiological characteristics and natural history of pediatric allergic rhinitis

Allergic rhinitis (AR) is one of the most common allergic diseases characterized by stuffy nose, rhinorrhea, sneezing, and itching. Researchers have indicated an increase in the prevalence of AR and younger-age onset during the last few decades. The increasing burden of AR has caused many researchers to investigate time trends of the prevalence of AR and to identify its risk factors. The most commonly used epidemiological studies are cross-sectional ones such as the International Study of Asthma and Allergies in Childhood study and big data from National Health Insurance Service or National Health and Nutrition Examination Survey. However, these studies have many limitations including recall bias, selection bias, and deficit of objective evaluation. Furthermore, crosssectional studies cannot reflect new risk factors associated with the development of AR. New epidemiological studies will be needed to cover genetic factors, environmental changes, microbiomes, and lifestyles that are known to be risk factors for AR. Further studies will be needed to determine the prevalence, natural history, and risk factors of AR in order to advance our understanding of the pathophysiology, prevention, and management of comorbidities of AR.

Associated Factors for Asthma Severity in Korean Children: A Korean Childhood Asthma Study

PURPOSE: Childhood asthma has a considerable social impact and economic burden, especially in severe asthma. This study aimed to identify the proportion of childhood asthma severity and to evaluate associated factors for greater asthma severity. METHODS: This study was performed on 667 children aged 5–15 years with asthma from the nationwide 19 hospitals in the Korean childhood Asthma Study (KAS). Asthma was classified as mild intermittent, mild persistent, and moderate/severe persistent groups according to the National Asthma Education and Prevention Program recommendations. Multinomial logistic regression models were used to identify the associated factors for greater asthma severity. RESULTS: Mild persistent asthma was most prevalent (39.0%), followed by mild intermittent (37.6%), moderate persistent (22.8%), and severe persistent asthma (0.6%). Onset later than 6 years of age (adjusted odds ratio [aOR], 1.69 for mild persistent asthma; aOR, 1.92 for moderate/severe persistent asthma) tended to increase asthma severity. Exposure to environmental tobacco smoke (aOR, 1.53 for mild persistent asthma; aOR, 1.85 for moderate/severe persistent asthma), and current dog ownership with sensitization to dog dander (aOR, 5.86 for mild persistent asthma; aOR, 6.90 for moderate/severe persistent asthma) showed increasing trends with greater asthma severity. Lower maternal education levels (aOR, 2.32) and no usage of an air purifier in exposure to high levels of outdoor air pollution (aOR, 1.76) were associated with moderate/severe persistent asthma. CONCLUSIONS: Modification of identified environmental factors associated with greater asthma severity might help better control childhood asthma, thereby reducing the disease burden due to childhood asthma.

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.

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.

Serum alanine aminotransferase levels are closely associated with metabolic disturbances in apparently healthy young adolescents independent of obesity / 소아과

PURPOSE: Liver metabolism plays a pivotal role in the development of metabolic disorders. We aimed to investigate the clinical and laboratory risk factors associated with alanine aminotransferase (ALT) levels in young adolescents from an urban population in Korea. METHODS: A population of 120 apparently healthy adolescents aged 12–13 years was included in the cross-sectional design study; 58 were overweight or obese and 62 were of normal weight. We estimated anthropometric and laboratory measurements, including waist-to-height ratio, blood pressure, insulin sensitivity, aspartate aminotransferases (AST), ALT, and lipid profiles. RESULTS: The mean ages of the overweight or obese and normal weight participants were 12.9±0.3 and 13.0±0.3 years, respectively. Height, weight, body mass index, waist circumference, waist-to-height ratio, systolic and diastolic blood pressure, AST, ALT, total cholesterol, low-density lipoprotein-cholesterol, triglyceride, insulin, and the homeostatic model assessment of insulin resistance (HOMA-IR) score were significantly higher and the high-density lipoprotein-cholesterol and quantitative insulin-sensitivity check index were significantly lower in the overweight/obese participants in comparison to the normal-weight participants (all P < 0.05). In multivariate linear regression analysis, waist-to-height ratio, systolic blood pressure, and HOMA-IR score were independently and positively associated with serum ALT levels. CONCLUSION: Screening for ALT levels in adolescents may help to differentiate those at risk of metabolic abnormalities and thus prevent disease progression at an early age.

Asthma Severity and the Controller Prescription in Children at 12 Tertiary Hospitals

PURPOSE: Guidelines need to be tailored to where they are applied. We aimed to describe the distinctive asthma severity profile and the pattern of controller prescription in Korean children. METHODS: Twelve pediatric allergists from tertiary medical centers reviewed medical records of all asthmatic children who visited their clinics between September 1 and November 30 of 2013. Controller prescriptions were re-classified into 4 categories, then the prevalence of each asthma severity category and the controller prescription patterns according to asthma severity assessed by a Western (Global Initiative for Asthma, GINA) and an Asia-Pacific (Japanese Pediatric GuideLine, JPGL) guideline were evaluated. RESULTS: A total of 840 cases were reviewed. Both GINA and JPGL revealed that 328 (39.0%) and 249 (29.6%) subjects had intermittent asthma whereas 24 (2.9%) and 21 (2.5%) subjects had severe persistent asthma, respectively. Although higher category controllers tended to be prescribed to those who had more severe asthma, there was much overlap in categories of prescribed controllers between groups with regard to asthma severities. Leukotriene receptor antagonists (LTRA) was the most frequently prescribed as a single controller (40%) or as an add-on medication (19%) in the group of asthmatic children <6 years. CONCLUSIONS: Korean children have distinctive patterns of asthma severity and management strategies with a lower prevalence of severe asthma and a preference toward LTRA rather than low dose inhaled corticosteroids (ICS) alone or add-on long-acting beta-agonist (LABA) in the group of <6 year-old asthmatics that has not been predicted in Western countries. Thus, strategies tailored to regional situations need to be developed and recommended.

The Interaction Between Prenatal Exposure to Home Renovation and Reactive Oxygen Species Genes in Cord Blood IgE Response is Modified by Maternal Atopy

PURPOSE: Although home renovation exposure during childhood has been identified as a risk factor for the development of allergy, there is limited information on the association between prenatal exposure to home renovation and cord blood (CB) IgE response. The aims of this study were to identify the effect of prenatal exposure to home renovation on CB IgE levels, and to investigate whether this exposure interacts with neonatal genes and whether the effect can be modified by maternal atopy. METHODS: This study included 1,002 mother-neonate pairs from the COhort for Childhood Origin of Asthma and allergic diseases (COCOA). Prenatal environmental factors were collected using a questionnaire. The levels of CB IgE were measured by the ImmunoCAP system, and DNA was extracted from CB. RESULTS: Exposure to home renovation during the prenatal period was associated with significantly higher levels of CB IgE only in neonates from atopic mothers, and the effect of renovation exposure on CB IgE levels persisted from 31 months before birth. Furthermore, prenatal exposure to home renovation increased the risk of CB IgE response interacting with polymorphisms of NRF2 and GSTP1 genes only in neonates from atopic mothers. CONCLUSIONS: Maternal atopy modified the effect of prenatal exposure to home renovation on CB serum IgE response as well as the interaction between the exposure and neonatal genes involved in the oxidative stress pathway. These findings suggest that the genetically susceptible offspring of atopic mothers may be more vulnerable to the effect of prenatal exposure to home renovation on the development of allergy.

Relationship between exhaled nitric oxide and small-airway dysfunction in children with asthma using spirometry and the impulse oscillometry system

PURPOSE: Fractional exhaled nitric oxide (FeNO) is a maker of airway inflammation, and impedance of low frequency in the impulse oscillometry system (IOS) reflects small-airway obstruction. We investigated the association of the FeNO level with IOS parameters and spirometry results in asthma patients. METHODS: Fifty-eight children with asthma (60.3%, male), mean age 8.3 years (range, 4.5-16.0 years), were enrolled in the study. Reactance and resistance at 5 Hz with IOS, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and forced expiratory flow 25%-75% of the vital capacity (FEF25%-75%) with spirometry and FeNO were measured in all patients. The Z-score of spirometry and IOS parameters and the mean level of FeNO were used for correlation and regression analysis. RESULTS: FeNO was not significantly associated with height, age, or other demographic parameters. There was a statistically significant correlation between spirometry results and IOS measurements. The FeNO level was not significantly correlated with IOS variables. After adjusting for height, sex, atopic status, and the use of inhaled corticosteroid, the FeNO level showed significant correlations with Z-score of FEV1/FVC (P=0.037, adjusted R 2=0.234). CONCLUSION: FeNO was significantly correlated with Z-scores of FEV1/FVC, but not with IOS variables. Therefore, FeNO may be used to detect whole airway obstruction, but not small-airway obstruction.

Prenatal Particulate Matter/Tobacco Smoke Increases Infants' Respiratory Infections: COCOA Study

PURPOSE: To investigate whether prenatal exposure to indoor fine particulate matter (PM2.5) and environmental tobacco smoke (ETS) affects susceptibility to respiratory tract infections (RTIs) in infancy, to compare their effects between prenatal and postnatal exposure, and to determine whether genetic factors modify these environmental effects. METHODS: The study population consisted of 307 birth cohort infants. A diagnosis of RTIs was based on parental report of a physician's diagnosis. Indoor PM2.5 and ETS levels were measured during pregnancy and infancy. TaqMan was used for genotyping of nuclear factor erythroid 2-related factor (Nrf2) (rs6726395), glutathione-S-transferase-pi (GSTP) 1 (rs1695), and glutathione-S-transferase-mu (GSTM) 1. Microarrays were used for genome-wide methylation analysis. RESULTS: Prenatal exposure to indoor PM2.5 increased the susceptibility of lower RTIs (LRTIs) in infancy (adjusted odds ratio [aOR]=2.11). In terms of combined exposure to both indoor PM2.5 and ETS, prenatal exposure to both pollutants increased susceptibility to LRTIs (aOR=6.56); however, this association was not found for postnatal exposure. The Nrf2 GG (aOR=23.69), GSTM1 null (aOR=8.18), and GSTP1 AG or GG (aOR=7.37) genotypes increased the combined LRTIs-promoting effects of prenatal exposure to the 2 indoor pollutants. Such effects of prenatal indoor PM2.5 and ETS exposure were not found for upper RTIs. CONCLUSIONS: Prenatal exposure to both indoor PM2.5 and ETS may increase susceptibility to LRTIs. This effect can be modified by polymorphisms in reactive oxygen species-related genes.

Clinical risk factors associated with the development of wheezing in children less than 2 years of age who required hospitalization for viral lower respiratory tract infections / 소아과

PURPOSE: Wheezing following viral lower respiratory tract infections (LRTIs) in children <2 years of age is an important risk factor for the development of asthma later in life; however, not all children with viral LRTIs develop wheezing. This study investigated risk factors for the development of wheezing during viral LRTIs requiring hospitalization. METHODS: The study included 142 children <2 years of age hospitalized for LRTIs with at least one virus identified as the cause and classified them into children diagnosed with LRTIs with wheezing (n=70) and those diagnosed with LRTIs without wheezing (n=72). RESULTS: There were no significant differences in the viruses detected between the two groups. Multivariate logistic regression analysis showed that, after adjusting for potentially confounding variables including sex and age, the development of wheezing was strongly associated with parental history of allergic diseases (adjusted odds ratio [aOR], 20.19; 95% confidence interval [CI], 3.22-126.48), past history of allergic diseases (aOR, 13.95; 95% CI, 1.34-145.06), past history of hospitalization for respiratory illnesses (aOR, 21.36; 95% CI, 3.77-120.88), exposure to secondhand smoke at home (aOR, 14.45; 95% CI, 4.74-44.07), and total eosinophil count (aOR, 1.01; 95% CI, 1.01-1.02). CONCLUSION: Past and parental history of allergic diseases, past history of hospitalization for respiratory illnesses, exposure to secondhand smoke at home, and total eosinophil count were closely associated with the development of wheezing in children <2 years of age who required hospitalization for viral LRTIs. Clinicians should take these factors into consideration when treating, counseling, and monitoring young children admitted for viral LRTIs.

Food allergen sensitization in young children with typical signs and symptoms of immediate-type food allergies: a comparison between monosensitized and polysensitized children / 소아과

PURPOSE: The clinical interpretation of children sensitized to allergens is challenging, particularly in children with food allergies. We aimed to examine clinical differences between children with monosensitization and those with polysensitization to common food allergens and to determine risk factors for polysensitization in young children <10 years of age with immediate-type food allergies. METHODS: The study included children <10 years of age with signs and symptoms indicative of immediate-type food allergies. Serum total IgE level was measured, and ImmunoCAP analysis for food allergens was performed. RESULTS: The mean age of the study subjects was 1.6+/-1.6 years (75 boys and 51 girls). Thirty-eight children (30.2%) were monosensitized and 88 children (69.8%) were polysensitized. Multivariate logistic regression analysis showed that the development of polysensitization to common food allergens was positively associated with a parental history of allergic rhinitis (adjusted odds ratio [aOR], 6.28; 95% confidence interval [CI], 1.78-22.13; P=0.004), season of birth (summer/fall) (aOR, 3.10; 95% CI, 1.10-8.79; P=0.033), and exclusive breastfeeding in the first 6 months of age (aOR, 3.51; 95% CI, 1.20-10.25; P=0.022). CONCLUSION: We found significant clinical differences between children with monosensitization and those with polysensitization to common food allergens and identified risk factors for the development of polysensitization in young children with immediate-type food allergies. Clinicians should consider these clinical risk factors when evaluating, counseling, treating, and monitoring young children with food allergies.

Fetal Intra-abdominal Umbilical Vein Varix Complicated with Patent Ductus Venosus and Atrial Septal Defect / 대한주산의학회잡지

Umbilical vein varix has diverse clinical features and an unpredictable course during the pregnancy and/or perinatal period. We report a rare case of isolated fetal varix of the intra-abdominal umbilical vein, which was associated with fetal cardiomegaly. After birth, the umbilical vein varix remained with continuous blood flow through the patent ductus venosus. In addition, persistent cardiomegaly was complicated with an atrial septal defect.

Sensitization patterns to common allergens in Korean children younger than 6 years of age presenting with typical symptoms or signs of allergic diseases: a single center study

PURPOSE: Population studies have reported that sensitization to inhalant allergens is rare in young children; however, most subjects in those studies had little or no symptoms or signs highly suggestive of allergic diseases. The aim of the present study was to assess the prevalence of sensitization to inhalant allergens in young children with symptoms and/or signs of allergic disease. METHODS: We analyzed the results of all specific IgE tests performed at our hospital laboratory in children younger than 6 years presenting with symptoms and/or signs highly suggestive of allergic diseases between 2008 and 2013. Specific IgE tests for Dermatophagoides pteronyssinus, Dermatophagoides farinae, Alternaria alternata, German cockroach, cat dander, egg white or egg yolk, milk, peanut, and soybean were performed on 295 children; a specific IgE concentration > or =0.35 or > or =0.2 IU/mL was considered positive. We also compared allergen sensitization rates using the two cutoff values. RESULTS: One hundred eighty-one children (61.4%) were positive to at least 1 allergen tested and 53 children (18.9%) were positive to at least 1 inhalant allergen when a specific IgE concentration > or =0.35 IU/mL was considered positive. The children were more likely to have asthma or allergic rhinitis when they were sensitized to any inhalant allergen, particularly house dust mites. The prevalence of sensitization to inhalant allergens increased with age (P<0.001). There was no significant difference in the prevalence of polysensitization among different age groups, but sensitization to both inhalant and food allergens significantly increased with age. CONCLUSION: Our results suggest that specific IgE tests to common inhalant allergens, particularly the house dust mites, may be considered when performing blood screening tests for young children presenting with symptoms and/or signs of allergic diseases.

Evaluation of lung function in children

Pulmonary function testing (PFT) is an important and fundamental method in the evaluation and treatment of respiratory diseases. Airway responsiveness assessed using histamine or methacholine by PFT is meaningful for the diagnosis of asthma. Spirometry is simple, and has been the most commonly used technique. However, in younger or uncooperative children, other commercially available tools such as impulse oscillometry (IOS), gas dilution, and plethysmography have been used. IOS is a noninvasive method that allows the measurement of airway mechanics (resistance [R] and reactance [X]) with minimal patient cooperation. Functional residual capacity (FRC) is one of the most important measurements obtained by gas dilution. Plethysmography is a gold standard to measure airway resistance and useful for lung function testing in infants. The purpose of this review is to help pediatric physicians being familiar with PFT techniques used in young children by discussing their principles, clinical applications, limitations, and current accessibility in Korea.

Determinants of sensitization to allergen in infants and young children / 소아과

Atopic sensitization is a complex phenomenon that changes dynamically with age throughout childhood; its prevalence increases with age in young children. Additionally, with increasing age, the prevalence of sensitization to inhalant allergens and the prevalence of polysensitization to allergens increase. It is also well established that the development of atopic sensitization is the result of a complex interplay of genetic and environmental factors. However, there is considerable heterogeneity in the literature in terms of the effect of different environmental exposures in young children on the subsequent risk of atopic sensitization and allergic diseases. Previous studies on the relationship, in early life, between pet ownership, sex, exposure to secondhand smoke, exposure to traffic-related air pollution components, and atopic sensitization have yielded different results. Recent studies have highlighted the importance of gene-environment interactions, especially during early childhood, on the risk of subsequent atopic sensitization and allergic diseases. Therefore, pediatricians should consider the genetic and environmental determinants of atopic sensitization in infants and young children when diagnosing and treating patients with allergic diseases. Determining ways in which early exposure to these risk factors in young children may be reduced could be beneficial in preventing the likelihood of developing atopic sensitization.

Phenotype and endotype in pediatric asthma

Asthma is not a homogeneous disease presenting variable clinical features, but a complex disorder consisting of many different disease entities characterized by variable air-flow limitation. To date, there are little effective preventive-strategies for the development of asthma, and it has been emphasized that early identification and intervention are the best ways to reduce the associated morbidities, quality of life, and socioeconomic burden. Predicting the natural course of asthma is still difficult, although various phenotypic approaches and predictive scores are developed and widely used. The present phenotypes and predictive scores may be reliable in the population, but those appear to be unreliable in each individual in real practice. Either undertreatment or overtreatment in childhood asthma is an important issue, because they are associated with poor compliance, increments of socioeconomic burdens, and poor quality of life. There is no doubt about the clinical efficacy of inhaled corticosteroid (ICS) in childhood asthma, but the negative effect of long-term use of ICS on the height is emerging. Therefore general physicians should consider an individualized management using specific phenotypes and endotypes, and regularly re-evaluate the drug-response, level of control, and adherence/compliance to avoid inadequate treatment.

Associations of matrix metalloproteinase (MMP)-8, MMP-9, and their inhibitor, tissue inhibitor of metalloproteinase-1, with obesity-related biomarkers in apparently healthy adolescent boys / 소아과

PURPOSE: Matrix metalloproteinases (MMPs) have been implicated in atherosclerosis, and therefore, are considered risk factors for metabolic dysfunction in adults. However, there is little data on circulating levels of MMPs and tissue inhibitors of MMPs (TIMPs) with regard to obesity-related biomarkers in the general adolescent population. In the present study, we determined the associations of MMP-8, MMP-9, and TIMP-1 levels and MMP-8/TIMP-1 and MMP-9/TIMP-1 ratios with obesity-related biomarkers in apparently healthy adolescent boys. METHODS: We measured MMP and TIMP concentrations in plasma samples using the enzyme-linked immunosorbent assay and analyzed their associations with obesity-related biomarkers, such as liver enzymes and lipid profiles, in a sample of 91 Korean boys aged 13-14 years who participated in a general health check-up. RESULTS: The mean age of the boys was 13.8+/-0.3 years; 72 boys were normal weight and 19 were overweight/obese. The Pearson correlation coefficients revealed a significant correlation between MMP-8 and aspartate aminotransferase (r=0.217, P=0.039) and alanine aminotransferase (r=0.250, P=0.017) and between TIMP-1 and aspartate aminotransferase (r=0.267, P=0.011). In a multivariate linear regression analysis, serum alanine aminotransferase was positively associated with the MMP-8 level. There were no significant differences in the MMP-8, MMP-9, and TIMP-1 levels or MMP-8/TIMP-1 and MMP-9/TIMP-1 ratios between control and overweight/obese subjects. CONCLUSION: We found a significant association between the MMP-8 level and alanine aminotransferase in the apparently healthy adolescent boys. These findings indicate that there may be a pathophysiological mechanism underlying the relationship between MMP-8 and liver enzymes in young adolescents.