Cutoff values of body mass index for severe obesity in Korean children and adolescents: the 99th percentile versus 120% of the 95th percentile

Purpose@#Several definitions for severe obesity have been used, primarily the 99th percentile of the body mass index (BMI) and 120% of the 95th BMI percentile. This study aimed to establish a standardized definition for severe obesity in children and adolescents in Korea. @*Methods@#The 99th BMI percentile line and 120% of the 95th BMI percentile line were constructed using 2017 Korean National Growth Charts. To compare these 2 cutoff points for severe obesity, we included 9,984 individuals (5,289 males and 4,695 females) aged 10–18 years with anthropometric data available from the Korean National Health and Nutrition Examination Survey 2007–2018. @*Results@#Although 120% of the 95th percentile of BMI is widely used as a definition of severe obesity, the 99th percentile is almost identical to 110% of the 95th percentile in Korea, according to the latest national BMI growth chart for children and adolescents. The prevalence rates of high blood pressure, high triglycerides, low high-density lipoprotein cholesterol, and high alanine aminotransferase in the participants whose BMI was ≥120% of the 95th percentile were higher than in those whose BMI was ≥99th percentile (P<0.001). @*Conclusion@#A cutoff value for severe obesity of ≥120% of the 95th percentile is appropriate in children and adolescents in Korea. To provide follow-up care for severely obese children and adolescents, it is necessary to add a new line at 120% of the 95th percentile to the national BMI growth chart.

ACTG2 Variants in Pediatric Chronic Intestinal Pseudo-obstruction With Megacystis

Background/Aims@#Chronic intestinal pseudo-obstruction (CIPO) is a clinically heterogeneous syndrome characterized by compromised peristalsis and intestinal obstruction. Variants of actin gamma 2 (ACTG2), a protein crucial for correct enteric muscle contraction, have been found in CIPO patients. The aim of this study is to examine the clinical features and ACTG2 variants in Korean patients with CIPO. @*Methods@#From January 1995 to August 2020, 12 patients diagnosed with CIPO were included and genetic analysis testing of ACTG2 was performed. @*Results@#Heterozygous ACTG2 missense variants were found in 6 patients (50.0%). The p.Arg257Cys variant was found in 3 patients, and p.Arg63Gln and p.Arg178His variants were found in 1 patient each. A novel variant, p.Ile193Phe, was found in 1 patient. Three patients were diagnosed at birth, 2 at the age of 1 year, and 1 at 3 years of age. Abnormal prenatal genitourinary ultrasonographic findings were found in all 6 patients; microcolon was found in 4 patients (66.7%), and megacystis in all 6 patients. The pathology showed abnormal ganglion cells as well as myopathic findings. All patients are dependent on total parenteral nutrition and are to date alive. @*Conclusions@#ACTG2 variants are commonly found in Korean patients with CIPO. In CIPO patients with megacystis and abnormal prenatal ultrasonography, genetic testing of ACTG2 should be considered. Molecular diagnosis of CIPO is more important than pathologic diagnosis.

MPV17-related Hepatocerebral Mitochondrial DNA Depletion Syndrome / 대한소화기학회지

Mitochondrial DNA (mtDNA) depletion syndrome comprises diseases resulting from a deficiency of proteins involved in mtDNA synthesis. MPV17 is a mitochondrial membrane protein whose mutation causes mitochondrial deoxynucleotide insufficiency.MPV17-related hepatocerebral mtDNA depletion syndrome is a rare autosomal recessive disease. This case report describes the clinical manifestations of MPV17-related hepatocerebral mtDNA depletion syndrome analyzed by performing whole-exome sequencing (WES). A 17-month-old girl presented with developmental delay, jaundice, and failure to thrive. The laboratory findings revealed cholestatic hepatitis, increased lactate-to-pyruvate ratio, and prolongation of the prothrombin time. She developed a hypoglycemic seizure. Brain magnetic resonance imaging revealed extensive demyelination of the white matter. WES detected the p.Leu151fs and p.Pro98Leu variants in MPV17. Her parents and sibling were found to be MPV17 heterozygous carriers. She was administered supportive treatment, such as replacement of fat-soluble vitamins and cornstarch to prevent further hypoglycemic events. The patient is currently being considered for liver transplantation. Overall, WES can help diagnose hepatocerebral mtDNA depletion syndrome in patients with hepatopathy, developmental delay, lactic acidosis, and hypomyelination based on brain magnetic resonance imaging.

Niemann-Pick Disease Type C Diagnosed Using Neonatal Cholestasis Gene Panel / 대한소화기학회지

Niemann-Pick disease type C (NPC) is a neurovisceral lysosomal storage disorder caused by mutations in the NPC1 and NPC2 genes. These mutations cause the accumulation of unesterified cholesterol and other lipids in the lysosomes. NPC has a broad spectrum of clinical manifestations, depending on the age of onset. A 15-day-old infant presented at the Seoul National University Children's Hospital with neonatal cholestasis and hepatosplenomegaly, with the onset of jaundice at 5 days of age. Despite supportive treatment, the patient was considered for a liver transplant because of progressive liver failure. Unfortunately, the patient died from gastrointestinal bleeding before undergoing the transplant. The neonatal cholestasis gene panel revealed two novel likely pathogenic variants in the NPC1 gene (c.1145C>G [p.Ser382*] and c.2231_2233del [p.Val744del]). The patient was diagnosed with NPC, and both parents were found to be carriers of each variant. In infants presenting with neonatal cholestasis, a gene panel can help diagnose NPC.

Hereditary Fructose Intolerance Diagnosed in Adulthood

Hereditary fructose intolerance (HFI) is an autosomal recessive disorder caused by a mutation in the aldolase B gene. HFI patients exhibit nausea, vomiting, abdominal pain, hypoglycemia, and elevated liver enzymes after dietary fructose exposure. Chronic exposure might lead to failure to thrive, liver failure, renal failure, and, eventually, death. HFI usually manifests in infants when they are being weaned off of breastmilk. Because HFI has an excellent prognosis when patients maintain a strict restrictive diet, some patients remain undiagnosed due to the voluntary avoidance of sweet foods. In the past, HFI was diagnosed using a fructose tolerance test, liver enzyme assays or intestinal biopsy specimens. Currently, HFI is diagnosed through the analysis of aldolase B mutations. Here, HFI was diagnosed in a 41-year-old woman who complained of sweating, nausea, and vomiting after consuming sweets. She had a compound heterozygous mutation in the aldolase B gene; gene analysis revealed pathogenic nonsense (c.178C>T, p.Arg60Ter) and frameshift (c.360_363delCAAA, p.Asn120LysfsTer32) variants. This is the first report of a Korean HFI patient diagnosed in adulthood.

MPV17-related Hepatocerebral Mitochondrial DNA Depletion Syndrome / 대한소화기학회지

Mitochondrial DNA (mtDNA) depletion syndrome comprises diseases resulting from a deficiency of proteins involved in mtDNA synthesis. MPV17 is a mitochondrial membrane protein whose mutation causes mitochondrial deoxynucleotide insufficiency.MPV17-related hepatocerebral mtDNA depletion syndrome is a rare autosomal recessive disease. This case report describes the clinical manifestations of MPV17-related hepatocerebral mtDNA depletion syndrome analyzed by performing whole-exome sequencing (WES). A 17-month-old girl presented with developmental delay, jaundice, and failure to thrive. The laboratory findings revealed cholestatic hepatitis, increased lactate-to-pyruvate ratio, and prolongation of the prothrombin time. She developed a hypoglycemic seizure. Brain magnetic resonance imaging revealed extensive demyelination of the white matter. WES detected the p.Leu151fs and p.Pro98Leu variants in MPV17. Her parents and sibling were found to be MPV17 heterozygous carriers. She was administered supportive treatment, such as replacement of fat-soluble vitamins and cornstarch to prevent further hypoglycemic events. The patient is currently being considered for liver transplantation. Overall, WES can help diagnose hepatocerebral mtDNA depletion syndrome in patients with hepatopathy, developmental delay, lactic acidosis, and hypomyelination based on brain magnetic resonance imaging.

Successful Treatment of a Korean Infant with Giant Cell Hepatitis with Autoimmune Hemolytic Anemia Using Rituximab / 대한소아소화기영양학회지

Giant cell hepatitis with autoimmune hemolytic anemia (AHA) is a rare disease of infancy characterized by the presence of both Coombs-positive hemolytic anemia and progressive liver disease with giant cell transformation of hepatocytes. Here, we report a case involving a seven-month-old male infant who presented with AHA followed by cholestatic hepatitis. The clinical features included jaundice, pallor, and red urine. Physical examination showed generalized icterus and splenomegaly. The laboratory findings suggested warm-type AHA with cholestatic hepatitis. Liver biopsy revealed giant cell transformation of hepatocytes and moderate lobular inflammation. The patient was successfully treated with four doses of rituximab. Early relapse of hemolytic anemia and hepatitis was observed, which prompted the use of an additional salvage dose of rituximab. He is currently in clinical remission.

A Nomogram for Predicting Non-Alcoholic Fatty Liver Disease in Obese Children / 대한소아소화기영양학회지

Purpose@#Non-alcoholic fatty liver disease (NAFLD) ranges in severity from simple steatosis to steatohepatitis. Early detection of NAFLD is important for preventing the disease from progressing to become an irreversible end-stage liver disease. We developed a nomogram that allows for non-invasive screening for NAFLD in obese children. @*Methods@#Anthropometric and laboratory data of 180 patients from our pediatric obesity clinic were collected. Diagnoses of NAFLD were based on abdominal ultrasonographic findings. The nomogram was constructed using predictors from a multivariate analysis of NAFLD risk factors. @*Results@#The subjects were divided into non-NAFLD (n=67) and NAFLD groups (n=113). Factors, including sex, body mass index, abdominal circumference, blood pressure, insulin resistance, and levels of aspartate aminotransferase, alanine aminotransferase (ALT), γ-glutamyl transpeptidase (γGT), uric acid, triglycerides, and insulin, were significantly different between the two groups (all p<0.05) as determined using homeostatis model assessment of insulin resistance (HOMA-IR). In our multivariate logistic regression analysis, elevated serum ALT, γGT, and triglyceride levels were significantly related to NAFLD development. The nomogram was established using γGT, uric acid, triglycerides, HOMA-IR, and ALT as predictors of NAFLD probability. @*Conclusion@#The newly developed nomogram may help predict NAFLD risk in obese children. The nomogram may also allow for early NAFLD diagnosis without the need for invasive liver biopsy or expensive liver imaging, and may also allow clinicians to intervene early to prevent the progression of NAFLD to become a more advanced liver disease.

Development of Hepatocellular Carcinoma in Patients with Glycogen Storage Disease: a Single Center Retrospective Study

BACKGROUND@#Glycogen storage disease (GSD) is an inherited disorder leading to abnormal glucose metabolism and glycogen accumulation, and is associated with various complications including hepatic adenoma and hepatocellular carcinoma. The aim of this study was to analyze the risk factors for hepatic adenoma and its malignant change, and the hepatocellular carcinoma-free survival rate in patients with GSD who developed adenoma.@*METHODS@#A total of 72 patients with GSD who were enrolled from March 1982 to September 2013 at Seoul National University Children's Hospital were retrospectively analyzed, and the median follow-up period was 19.2 years.@*RESULTS@#Thirty-two patients (44.4%) developed hepatic adenoma at an age range of 7.9–26.3 years (median, 14.3 years). Among the 32 patients with hepatic adenoma, 4 patients (12.5%) developed hepatocellular carcinoma on an average interval of 6.7 years between the diagnosis of adenoma and the development of hepatocellular carcinoma. GSD type I and portacaval shunt operation were found to be the risk factors for hepatic adenoma development. The hepatocellular carcinoma-free survival rate at 10 years from adenoma development was 82%.@*CONCLUSION@#The present study found that portacaval shunt operation increases the risk of development of hepatic adenoma in GSD patients, especially in GSD type I. The hepatic adenoma in GSD patients has a potential of malignant transformation, which should be keep in mind in follow-up process of the disease.

Development of Hepatocellular Carcinoma in Patients with Glycogen Storage Disease: a Single Center Retrospective Study

BACKGROUND@#Glycogen storage disease (GSD) is an inherited disorder leading to abnormal glucose metabolism and glycogen accumulation, and is associated with various complications including hepatic adenoma and hepatocellular carcinoma. The aim of this study was to analyze the risk factors for hepatic adenoma and its malignant change, and the hepatocellular carcinoma-free survival rate in patients with GSD who developed adenoma.@*METHODS@#A total of 72 patients with GSD who were enrolled from March 1982 to September 2013 at Seoul National University Children's Hospital were retrospectively analyzed, and the median follow-up period was 19.2 years.@*RESULTS@#Thirty-two patients (44.4%) developed hepatic adenoma at an age range of 7.9–26.3 years (median, 14.3 years). Among the 32 patients with hepatic adenoma, 4 patients (12.5%) developed hepatocellular carcinoma on an average interval of 6.7 years between the diagnosis of adenoma and the development of hepatocellular carcinoma. GSD type I and portacaval shunt operation were found to be the risk factors for hepatic adenoma development. The hepatocellular carcinoma-free survival rate at 10 years from adenoma development was 82%.@*CONCLUSION@#The present study found that portacaval shunt operation increases the risk of development of hepatic adenoma in GSD patients, especially in GSD type I. The hepatic adenoma in GSD patients has a potential of malignant transformation, which should be keep in mind in follow-up process of the disease.

Development of Hepatocellular Carcinoma in Patients with Glycogen Storage Disease: a Single Center Retrospective Study

Clinical Practice Guideline for the Diagnosis and Treatment of Pediatric Obesity: Recommendations from the Committee on Pediatric Obesity of the Korean Society of Pediatric Gastroenterology Hepatology and Nutrition / 대한소아소화기영양학회지

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.

Clinical Aspects and Treatments for Pediatric Inflammatory Bowel Diseases / 대한소아소화기영양학회지

The incidence of pediatric inflammatory bowel disease (IBD) is increasing worldwide, especially in the developing countries. It differs from adult disease in clinical manifestations, especially with regard to genetic predisposition in monogenic IBD. Pediatric disease also have a tendency to show more aggressive inflammation and greater extent of lesion. Newer drugs such as anti-tumor necrosis factor α have been known to make a difference in treating pediatric IBD. Recent studies suggested that the patients with high risk factors might have some benefits from earlier use of biologics. To achieve treatment goals such as relieving symptoms, optimizing growth, and improving quality of life while minimizing drug toxicity, more research is needed to develop tools for risk stratification in the use of biologics for pediatric IBD.

Clinical practice guideline for the diagnosis and treatment of pediatric obesity: recommendations from the Committee on Pediatric Obesity of the Korean Society of Pediatric Gastroenterology Hepatology and Nutrition / 소아과

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.

Association Between Vitamin D Deficiency and Suspected Nonalcoholic Fatty Liver Disease in an Adolescent Population / 대한소아소화기영양학회지

PURPOSE: Vitamin D deficiency is a condition widespread throughout the world. Recent studies have suggested that vitamin D deficiency was associated with obesity and metabolic syndrome. The purpose of the study was to examine the relationship between vitamin D deficiency and nonalcoholic fatty liver disease (NAFLD) in adolescents. METHODS: The data were obtained from the Korean National Health and Nutrition Examination Survey from 2008–2014. A total of 3,878 adolescents were included in the study. Vitamin D deficiency was defined as a 25-hydroxyvitamin D concentration 30 U/L. RESULTS: Vitamin D deficiency was noted in 78.9% of the studied population. Age, body mass index, waist circumference, and blood pressure, glucose, cholesterol, and triglyceride levels were significantly higher in adolescents with suspected NAFLD than in adolescents without suspected NAFLD, while the mean vitamin D level was significantly lower in adolescents with suspected NAFLD. The multivariate-adjusted odds of suspected NAFLD were higher with increased age, male gender, obesity, and metabolic syndrome. Individuals with vitamin D deficiency were at higher risk of suspected NAFLD (odds ratio, 1.77; 95% confidence interval, 1.07–2.95) after adjusting for age, gender, obesity, and metabolic syndrome. CONCLUSION: Vitamin D deficiency was associated with suspected NAFLD, independent of obesity and metabolic syndrome, in adolescents.

Benign Recurrent Intrahepatic Cholestasis Type 2 in Siblings with Novel ABCB11 Mutations / 대한소아소화기영양학회지

Benign recurrent intrahepatic cholestasis (BRIC), a rare cause of cholestasis, is characterized by recurrent episodes of cholestasis without permanent liver damage. BRIC type 2 (BRIC2) is an autosomal recessive disorder caused by ABCB11 mutations. A 6-year-old girl had recurrent episodes of jaundice. At two months of age, jaundice and hepatosplenomegaly developed. Liver function tests showed cholestatic hepatitis. A liver biopsy revealed diffuse giant cell transformation, bile duct paucity, intracytoplasmic cholestasis, and periportal fibrosis. An ABCB11 gene study revealed novel compound heterozygous mutations, including c.2075+3A>G in IVS17 and p.R1221K. Liver function test results were normal at 12 months of age. At six years of age, steatorrhea, jaundice, and pruritus developed. Liver function tests improved following administration of phenylbutyrate and rifampicin. Her younger brother developed jaundice at two months of age and his genetic tests revealed the same mutations as his sister. This is the first report of BRIC2 confirmed by ABCB11 mutations in Korean siblings.

Nationwide Survey for Application of ROME IV Criteria and Clinical Practice for Functional Constipation in Children

BACKGROUND: This study aimed to investigate the awareness and application of ROME IV criteria for functional constipation (FC) in real-world practices and assessed differences between pediatric gastroenterologists (PGs) and general pediatricians. METHODS: A total of 239 (47.8%) out of 500 nationwide pediatricians answered a questionnaire for diagnosis and management of pediatric FC; 60 were PGs (75% of total PGs in Korea). RESULTS: A total of 16.6% of pediatricians were aware of the exact ROME IV criteria. Perianal examination and digital rectal examination were practiced less, with a higher tendency among PGs (P 6 months (63.8%) than 1-year were lactulose (59.1%), followed by polyethylene glycol (PEG) 4000 (17.7%), and probiotics (11.8%). Prescription priority significantly differed between PGs and general pediatricians; lactulose or PEG 4000 were most commonly prescribed by PGs (89.7%), and lactulose or probiotics (75.7%) were prescribed by general pediatricians (P < 0.001). For patients aged < 1-year, lactulose (41.6%) and changing formula (31.7%) were commonly prescribed. Most participants recommended diet modification, and PGs more frequently used defecation diary (P = 0.002). CONCLUSION: Discrepancies between actual practice and Rome IV criteria and between PGs and general pediatricians were observed. This survey may help construct practice guidelines and educational programs for pediatric FC.

Endoscopic Management of Pancreaticopleural Fistula in a Child with Hereditary Pancreatitis / 대한소아소화기영양학회지

Pancreaticopleural fistula (PPF) a fistulous connection between the pancreas and pleural space due to prolonged chronic pancreatitis (CP). PPF is a very rare complication which presents in 0.4% of chronic pancreatitis cases, especially among children. We report a case involving a 3-year-old boy who presented with pleural effusion caused by a PPF, a complication of hereditary pancreatitis, which was, for the first time in Korea, successfully managed with endoscopic treatment. Chest radiography and computed tomography showed massive pleural effusion. Percutaneous catheter drainage was performed. High amylase levels were observed in the pleural fluid and serum, suggesting PPF. The patient was managed with bowel rest and octreotide infusion. Endoscopic retrograde cholangiopancreatography revealed CP, and pleural effusion was successfully managed with stent placement. PRSS1 genetic screening revealed R122H mutation.

Use of Anti-TNF Alpha Blockers Can Reduce Operation Rate and Lead to Growth Gain in Pediatric Crohn's Disease / 대한소아소화기영양학회지

PURPOSE: Pediatric Crohn's disease (CD) is directly related to growth and has a high probability of requiring surgical intervention(s); therefore, more active treatment for CD is required for children. This study investigated the impact of biologics on growth and disease course associated with surgery. METHODS: This was a retrospective cohort study involving patients diagnosed with CD at the Seoul National University Children's Hospital (Seoul, Korea) between January 2006 and October 2017. The aim was to determine the characteristics of pediatric patients with CD and whether biologics affected growth and the surgical disease course. RESULTS: Among patients who underwent surgery for CD, the mean number of operations per patient was 1.89. The mean time from initial diagnosis to surgery was 19.3 months. The most common procedure was fistulectomy (34%), followed by incision and drainage (25%). In all patients, the use of biologics increased the height (p=0.002) and body mass index (BMI) (p=0.005). Among patients who underwent surgery, height (p=0.004) and BMI (p=0.048) were increased in the group using biologics. Patients who used biologics exhibited a low operation rate only within 2 years after diagnosis, with no differences thereafter (p=0.027). CONCLUSION: Although biologics could not mitigate the operation rate in pediatric patients who underwent surgery for CD, biological therapy delayed disease progression within 2 years of disease onset. Additionally, biologics conferred growth and BMI benefits in this window period. Therefore, it may be helpful to use biologics for optimal growth in pediatric patients with a high probability of undergoing future surgery.

Multiplex Ligation-dependent Probe Amplification Analysis Subsequent to Direct DNA Full Sequencing for Identifying ATP7B Mutations and Phenotype Correlations in Children with Wilson Disease

BACKGROUND: Mutations in ATP7B cause Wilson disease (WD). However, direct DNA full sequencing cannot detect all mutations in patients with WD. Multiplex ligation-dependent probe amplification (MLPA) analysis is reportedly useful in increasing the diagnostic yield in other genetic disorders with large deletions or insertions. The aim of this study was to evaluate whether the detection rate of ATP7B mutations can be increased by using MLPA. METHODS: We enrolled 114 children with WD from 104 unrelated families based on biochemical tests and direct DNA full sequencing. The patients with one or zero mutant allele were investigated using MLPA. We analyzed phenotypic correlations. RESULTS: Total allele frequency by full sequencing was 87.5%. Full sequencing revealed two mutant alleles in 80 of 104 unrelated children. One mutant allele was detected in 22 children, and no mutations were found in two children. Novel mutations including small deletions with frameshift mutations were identified by DNA sequencing. MLPA revealed no gross deletion or duplication in 24 children with one or zero mutant alleles. The number of detected mutations was not associated with hepatic manifestation, age of onset, Kayser-Fleischer ring, ceruloplasmin, and urinary Cu concentrations. CONCLUSION: MLPA showed a limited role to increase the mutation detection rate in children who do not receive a definite genetic diagnosis of WD through DNA full sequencing. This finding suggests that large deletions or duplications might be extremely rare in WD. Further development is needed to improve the genetic diagnosis of WD.