Growth charts are curves or tables that facilitate the visualization of anthropometric parameters, and are widely used as an important indicator when evaluating the growth status of children and adolescents. The latest version of the Korean National Growth Charts released in 2007 has raised concerns regarding the inclusion of data from both breastfed and formula-fed infants, higher body mass index (BMI) values in boys, and smaller 3rd percentile values in height-for-age charts. Thus, new growth charts have been developed to improve the previous version. The 2006 World Health Organization Child Growth Standards, regarded as the standard for breastfed infants and children, were introduced for children aged 0–35 months. For children and adolescents aged 3–18 years, these new growth charts include height-for-age, weight-for-age, BMI-for-age, weight-for-height, and head circumference-for-age charts, and were developed using data obtained in 1997 and 2005. Data sets and exclusion criteria were applied differently for the development of the different growth charts. BMI-for-age charts were adjusted to decrease the 95th percentile values of BMI. Criteria for obesity were simplified and defined as a BMI of ≥95th percentile for age and sex. The 3rd percentile values for height-for-age charts were also increased. Additional percentile lines (1st and 99th) and growth charts with standard deviation lines were introduced. 2017 Korean National Growth Charts are recommended for the evaluation of body size and growth of Korean children and adolescents for use in clinics and the public health sector in Korea.

The Committee on Pediatric Obesity of the Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition newly developed the first Korean Guideline on the Diagnosis and Treatment of Obesity in Children and Adolescents to deliver an evidence-based systematic approach to childhood obesity in South Korea. The following areas were systematically reviewed, especially on the basis of all available references published in South Korea and worldwide, and new guidelines were established in each area with the strength of recommendations based on the levels of evidence: (1) definition and diagnosis of overweight and obesity in children and adolescents; (2) principles of treatment of pediatric obesity; (3) behavioral interventions for children and adolescents with obesity, including diet, exercise, lifestyle, and mental health; (4) pharmacotherapy; and (5) bariatric surgery.

Recent studies on pediatric inflammatory bowel disease (IBD) have revealed that early-onset IBD has distinct phenotypic differences compared with adult-onset IBD. In particular, very early-onset IBD (VEO-IBD) differs in many aspects, including the disease type, location of the lesions, disease behavior, and genetically attributable risks. Several genetic defects that disturb intestinal epithelial barrier function or affect immune function have been noted in these patients from the young age groups. In incidence of pediatric IBD in Korea has been increasing since the early 2000s. Neonatal or infantile-onset IBD develops in less than 1% of pediatric patients. Children with “neonatal IBD” or “infantile-onset IBD” have higher rates of affected first-degree relatives, severe disease course, and a high rate of resistance to immunosuppressive treatment. The suspicion of a monogenic cause of VEO-IBD was first confirmed by the discovery of mutations in the genes encoding the interleukin 10 (IL-10) receptors that cause impaired IL-10 signaling. Patients with such mutations typically presented with perianal fistulae, shows a poor response to medical management, and require early surgical interventions in the first year of life. To date, 60 monogenic defects have been identified in children with IBD-like phenotypes. The majority of monogenic defects presents before 6 years of age, and many present before 1 year of age. Next generation sequencing could become an important diagnostic tool in children with suspected genetic defects especially in children with VEO-IBD with severe disease phenotypes. VEO-IBD is a phenotypically and genetically distinct disease entity from adult-onset or older pediatric IBD.

Infantile periods may have stronger genetic influences. Recently, studies on genetic defects in the interleukin-10 (IL-10) signaling pathway have provided new insights into inflammatory bowel disease (IBD). This study is to reveal whether mutations of IL-10 signaling pathway genes contribute to the phenotypes of IBD. Forty children who were diagnosed with IBD below the age of 10 years were enrolled. We sequenced the genes interleukin-10 receptor A (IL-10RA), IL-10RB and IL-10, and analyzed the clinical characteristics of very early-onset IBD (VEO-IBD). In total, 14 out of the 40 children developed their symptoms within 1 year of age. We found mutations in IL-10RA in 7 out of the 40 children (17.5%). All seven children had developed symptoms within the first year of life. Particularly, half of the children with infantile-onset IBD had IL-10RA mutations. None of the remaining 26 children diagnosed above 1 year of age had IL-10RA mutations. No mutations were found in IL-10RB and IL-10. Identified IL-10RA mutations were p.(R101W), p.(Y91C), p.(R262C), p.(R117H) and p.(W69R). IL-10RA mutations were associated with onset of infancy (P<0.001), perianal fistulae (P<0.001), poor response to medical management (P=0.017) and early surgical interventions (P<0.001). VEO-IBD in infancy is phenotypically and genetically different disease entity from adult-onset or older child-onset IBD. It has a strong association with IL-10 receptor gene. We should consider the genotyping of genes of the IL-10 signaling pathway including IL-10RA in patients with VEO-IBD, especially in whom with onset of perianal fistulae and severe colitis.

PurposeForeign body (FB) ingestion is common in children, and button battery (BB) ingestion has been increasing in recent years. This study was to identify factors related to outcomes of FB ingestion, particularly BBs in the stomach. We evaluated whether the current recommendations are appropriate and aimed to suggest indications for endoscopic removal of BB in the stomach in young children.MethodsWe investigated patient age, shape, size, location of FBs, spontaneous passage time and resulting complications among 76 children. We observed types, size, location of BB and outcomes, and analyzed their associations with complications.ResultsCoins and BB were the two most common FBs. Their shapes and sizes were not associated with the spontaneous passage time. Size, spontaneous passage time, and age were also not associated with any specific complications. For BB ingestion, all 5 cases with lithium batteries (≥1.5 cm, 3 V) presented moderate to major complications in the esophagus and stomach without any symptoms, even when the batteries were in the stomach and beyond the duodenum, while no complications were noted in 7 cases with alkaline batteries (<1.5 cm, 1.5 V) (p=0.001). All endoscopies were conducted within 24 hours after ingestion.ConclusionThe type and voltage of the battery should be considered when determining whether endoscopy is required to remove a BB in the stomach. For lithium battery ingestion in young children, urgent endoscopic removal might be important in order to prevent complications, even if the child is asymptomatic and the battery is smaller than 2 cm.

A few published clinical studies have evaluated the association between gut microbiota in intractable epilepsy, but with inconsistent results. We hypothesized that the factors associated with the gut bacterial composition, such as age and geography, contributed to the discrepancies. Therefore, we used a cohort that was designed to minimize the effects of possible confounding factors and compared the gut microbiota between children with intractable epilepsy and healthy controls. Eight children with intractable epilepsy aged 1 to 7 years and 32 age-matched healthy participants were included. We collected stool samples and questionnaires on their diet and bowel habits at two time points and analyzed the gut microbiota compositions. In the epilepsy group, the amount of Bacteroidetes was lower (Mann–Whitney test, false discovery rate (FDR) < 0.01) and the amount of Actinobacteria was higher (FDR < 0.01) than in the healthy group. The epilepsy subjects were 1.6- to 1.7-fold lower in microbiota richness indices (FDR < 0.01) and harbored a distinct species composition (p < 0.01) compared to the healthy controls. Species biomarkers for intractable epilepsy included the Enterococcus faecium group, Bifidobacterium longum group, and Eggerthella lenta, while the strongest functional biomarker was the ATP-binding cassette (ABC) transporter. Our study identified gut bacterial dysbiosis associated with intractable epilepsy within the cohort that was controlled for the factors that could affect the gut microbiota.

BackgroundHenoch-Schӧnlein purpura (HSP) is a common vasculitis of childhood. Though HSP is usually self-limiting, severe complications can occur. The management for this condition has not been established yet. Thus, this nationwide study aimed at investigating epidemiological characteristics of children with HSP in Korea. The patterns of clinical practice with regard to the complications of the condition were also investigated.MethodsThis is a national population-based study that used the National Health Insurance Database. Children below 18 years who were diagnosed with HSP in Korea between 2006 and 2015 were enrolled. Data, such as age, sex, yearly and monthly distribution of HSP, hospitalization, re-hospitalization, comorbidities, and interventions were obtained. The use of steroids was also analyzed.ResultsA total of 56,841 children were enrolled. The annual incidence of HSP was 55.9 per 100,000 children. The peak age was 5 years. Spring was the most prevalent season. Sex (male) and young age (< 9 years) were risk factors of hospitalization. Younger children were more likely to be re-hospitalized and suspected with intussusception, arthritis, and nephritis. Only 4 children received laparotomy. In total, 57% were managed with steroids, and mean durations of medication were 4–5 days. Children who were hospitalized and those with comorbidities used steroids more frequently (P < 0.001).ConclusionThe annual incidence of HSP is 55.9 per 100,000 children which is higher in Korea than that in other countries. Younger children can have a more severe clinical course. This nationwide survey provides valuable information to understand HSP in children and to inspire further research on HSP.

BackgroundThis study aimed to explore changes in clinical epidemiology and genotype distribution and their association among hospitalized children with rotavirus gastroenteritis after the introduction of vaccines.MethodsBetween November 2010 and October 2014, hospitalized children with acute gastroenteritis were enrolled. Rotavirus genotypes were confirmed through reverse transcription-polymerase chain reaction (RT-PCR), semi-nested PCR, and sequencing. Clinical information including vaccination status and the modified Vesikari scores were collected.ResultsAmong 179 children with rotavirus infection, nineteen (10.6 %) were completely vaccinated. During the study period, the number of children between three and 23 months of age decreased significantly compared to the number of children older than 24 months of age (P = 0.010), who showed lower diarrhea severity (duration, P = 0.042; frequency, P = 0.021) but higher vomiting severity (P = 0.007, 0.036) compared to the former. Vaccination status was also significantly associated with lower vomiting severity after adjustment for age (frequency only, P = 0.018). The predominant genotypes were G2P[4] (18.4 %), G1P[8] (14.5 %), and G1P[4]P[8] (12.8 %), and the prevalence of genotypes with uncommon and mixed combinations was more than 50 %. Children infected with G2P[4] strains tended to be older (P = 0.005) and had more severe vomiting (P = 0.018, 0.006) than those with G1P[8].ConclusionsIncrease in age of infected, hospitalized children was accompanied by change in clinical severity during 2011–2014 after the introduction of vaccines in Seoul. Clinical severity was also associated with vaccination status and genotype. Long-term large scale studies are needed to document the significance of the increase in genotypes of uncommon and mixed combinations.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-016-1623-y) contains supplementary material, which is available to authorized users.