Prevalence of Inflammatory Bowel Disease Unclassified, as Estimated Using the Revised Porto Criteria, among Korean Pediatric Patients with Inflammatory Bowel Disease.

Purpose: Few studies have reported the prevalence of inflammatory bowel disease unclassified (IBDU) among Korean pediatric IBD (PIBD) population. To address this gap, we used two tertiary centers and nationwide population-based healthcare administrative data to estimate the prevalence of Korean pediatric IBDU at the time of diagnosis. Methods: We identified 136 patients aged 2-17 years with newly diagnosed IBD (94 Crohn's disease [CD] and 42 ulcerative colitis [UC]) from two tertiary centers in Korea between 2005 and 2017. We reclassified these 136 patients using the revised Porto criteria. To estimate the population-based prevalence, we analyzed Korean administrative healthcare data between 2005 and 2016, which revealed 3,650 IBD patients, including 2,538 CD and 1,112 UC. By extrapolating the reclassified results to a population-based dataset, we estimated the prevalence of PIBD subtypes. Results: Among the 94 CD, the original diagnosis remained unchanged in 93 (98.9%), while the diagnosis of one (1.1%) patient was changed to IBDU. Among the 42 UC, the original diagnosis remained unchanged in 13 (31.0%), while the diagnoses in 11 (26.2%), 17 (40.5%), and one (2.4%) patient changed to atypical UC, IBDU, and CD, respectively. The estimated prevalences of CD, UC, atypical UC, and IBDU in the Korean population were 69.5%, 9.4%, 8.0%, and 13.1%, respectively. Conclusion: This study is the first in Korea to estimate the prevalence of pediatric IBDU. This prevalence (13.1%) aligns with findings from Western studies. Large-scale prospective multicenter studies on PIBDU are required to examine the clinical features and outcomes of this condition.

Efficacy and safety of D-penicillamine, trientine, and zinc in pediatric Wilson disease patients.

OBJECTIVES: Wilson disease (WD) is a rare genetic disease affecting copper metabolism and the biliary tract's copper excretion. Lifelong medication is necessary to prevent liver failure, neurological complications, and death. Although D-penicillamine (DPA), trientine, and zinc are used to treat WD, there is limited research on the long-term outcomes of these drugs, especially in children. This study aimed to evaluate the efficacy and safety of DPA, trientine, and zinc in patients diagnosed with WD during childhood. METHODS: Ninety out of 92 patients were included in the analysis, excluding two patients who underwent liver transplantation without drug treatment due to an acute liver failure diagnosis. Treatment outcomes and reasons for discontinuation of therapy in 148 treatment blocks (37 DPA, 50 trientine, and 61 zinc) were analyzed using Kaplan-Meier analysis. RESULTS: The median age at diagnosis was 8.3 years. There was a statistically significant difference in drug changes due to treatment ineffectiveness among the three drugs: trientine (22/50, 44%), zinc (15/61, 25%), and DPA (2/37, 5%) (all p < 0.05). Regarding drug changes due to adverse effects, the rate was the highest for DPA, followed by zinc and trientine. There were significant differences between DPA and zinc, zinc and trientine (all p < 0.05), but no significant difference was observed between DPA and zinc (p = 0.22). CONCLUSIONS: In pediatric WD, DPA, zinc, and trientine have therapeutic effects in that order. However, DPA and zinc are associated with more adverse effects compared to trientine.

Characteristics of chronic enteropathy associated with SLCO2A1 gene (CEAS) in children, a unique type of monogenic very early-onset inflammatory bowel disease.

BACKGROUND:  Chronic enteropathy associated with SLCO2A1 gene (CEAS) is a unique type of inflammatory bowel disease. CEAS is monogenic disease and is thought to develop from childhood, but studies on pediatric CEAS are scarce. We analyzed characteristics of pediatric CEAS. METHODS: Eleven patients diagnosed with CEAS at Seoul National University Children's Hospital were identified and analyzed. Clinical data of patients were collected. Sanger sequencing of SLCO2A1 was performed on all patients. RESULTS: Patients were diagnosed at a median age of 16.0 years (IQR 11.0 ~ 20.0), and the median age at symptoms onset was only 4.0 years (IQR 2.5 ~ 6.0). Growth delay was observed at the time of diagnosis. Patients showed multiple ulcers or strictures in the small intestine, while the esophagus and colon were unaffected in any patients. Almost half of the patients underwent small intestine resection. The major laboratory features of pediatric CEAS include iron deficiency anemia (IDA), hypoalbuminemia, and near-normal levels of C-reactive protein (CRP). Two novel mutations of SLCO2A1 were identified. The most prevalent symptoms were abdominal pain and pale face. None of the immunomodulatory drugs showed a significant effect on CEAS. CONCLUSIONS: Pediatric CEAS typically develop from very young age, suggesting it as one type of monogenic very early onset inflammatory bowel disease. CEAS can cause growth delay in children but there is no effective treatment currently. We recommend screening for SLCO2A1 mutations to pediatric patients with chronic IDA from a young age and small intestine ulcers without elevation of CRP levels.

Serum Eosinophilic Cationic Protein as a Useful Noninvasive Marker of Eosinophilic Gastrointestinal Disease in Children.

Purpose: Recently, the prevalence of eosinophilic gastrointestinal disease (EGID) has shown an increasing trend worldwide. As the diagnosis of EGID requires invasive endoscopy with biopsy, noninvasive markers for detecting EGID in suspected patients, particularly children, are urgently needed. Therefore, this study aimed to evaluate the diagnostic accuracy of serum eosinophil cationic protein (ECP) beyond peripheral eosinophil counts in pediatric patients with EGID. Methods: Overall, 156 children diagnosed with EGID were enrolled and 150 children with functional abdominal pain disorder (FAPD) were recruited as controls. All participants underwent endoscopic biopsy in each segment of the gastrointestinal (GI) tract and serum ECP measurement, as well as peripheral eosinophil percent and absolute eosinophil count. Results: Comparing EGID (n=156) with FAPD (n=150) patients, serum ECP levels were significantly higher in pediatric patients with EGID than in those with FAPD (25.8±28.6 µg/L vs. 19.5±21.0 µg/L, p=0.007), while there was no significant difference in peripheral eosinophil percent and absolute eosinophil counts between the two groups. Serum ECP levels were correlated with peripheral eosinophil percent (r=0.593, p<0.001) and the absolute eosinophil count (r=0.660, p<0.001). The optimal cutoff value of serum ECP for pediatric EGID was 10.5 µg/mL, with a sensitivity of 69.9% and a specificity of 43.4% with an area under the receiver operating characteristic curve of 0.562. Conclusion: The combination of serum ECP levels and peripheral eosinophil counts, when employed with appropriated thresholds, could serve as a valuable noninvasive biomarker to distinguish between EGID and FAPD in pediatric patients manifesting GI symptoms.

Diagnostic algorithm for neonatal intrahepatic cholestasis integrating single-gene testing and next-generation sequencing in East Asia.

BACKGROUND AND AIM: Advances in molecular genetics have uncovered causative genes responsible for neonatal cholestasis. Panel-based next-generation sequencing has been used clinically in infants with neonatal cholestasis. We aimed to evaluate the clinical application of single-gene testing and next-generation sequencing and to develop a diagnostic algorithm for neonatal intrahepatic cholestasis. METHODS: From January 2010 to July 2021, patients suspected of having neonatal intrahepatic cholestasis were tested at the Seoul National University Hospital. If there was a clinically suspected disease, single-gene testing was performed. Alternatively, if it was clinically difficult to differentiate, a neonatal cholestasis gene panel test containing 34 genes was performed. RESULTS: Of the total 148 patients examined, 49 (33.1%) were received a confirmed genetic diagnosis, including 14 with Alagille syndrome, 14 with neonatal intrahepatic cholestasis caused by citrin deficiency, 7 with Dubin-Johnson syndrome, 5 with arthrogryposis-renal dysfunction-cholestasis syndrome, 5 with progressive familial intrahepatic cholestasis type II, 1 with Rotor syndrome, 1 with Niemann-Pick disease type C, 1 with Kabuki syndrome, and 1 with Phenylalanyl-tRNA synthetase subunit alpha mutation. Sixteen novel pathogenic or likely pathogenic variants of neonatal cholestasis were observed in this study. Based on the clinical characteristics and laboratory findings, we developed a diagnostic algorithm for neonatal intrahepatic cholestasis by integrating single-gene testing and next-generation sequencing. CONCLUSIONS: Alagille syndrome and neonatal intrahepatic cholestasis caused by citrin deficiency were the most common diseases associated with genetic neonatal cholestasis. Single-gene testing and next-generation sequencing are important and complementary tools for the diagnosis of genetic neonatal cholestasis.

PARVB and HSD17B13 variants are associated with nonalcoholic fatty liver disease in children.

BACKGROUND AND AIM: The aim of this study was to investigate the comprehensive genetic effects of exploratory variants of LYPLAL1, GCKR, HSD17B13, TRIB1, APOC3, MBOAT7, and PARVB on pediatric nonalcoholic fatty liver disease in addition to the previously reported variants of TM6SF2, PNPLA3, and SAMM50 in Korean children. METHODS: A prospective case-control study was conducted involving 309 patients diagnosed using ultrasound and 339 controls. Anthropometric measurements, liver function tests, and metabolic marker analysis were conducted, and fibrosis scores were calculated. Transient elastography was performed in 69 some patients with nonalcoholic fatty liver disease. TaqMan allelic discrimination assays were used for genotyping. The genetic risk scores were calculated using significant variants, namely, HSD17B13, PARVB, PNPLA3, SAMM50, and TM6SF2, to evaluate the additive effect. RESULTS: Risk allele carriers of the PARVB variant showed significantly higher levels of aminotransferases, gamma-glutamyl transferase, alkaline phosphatase, pediatric nonalcoholic fatty liver disease fibrosis score, and aspartate aminotransferase/platelet ratio index. Individuals with a homozygous variant of HSD17B13 showed significantly lower levels of aminotransferase, gamma-glutamyl transferase, liver stiffness measurement, and aspartate aminotransferase/platelet ratio index than those with other genotypes. These parameters did not significantly differ among other variants of LYPLAL1, GCKR, TRIB1, APOC3, and MBOAT7. The genetic risk scores was identified as an independent risk factor for nonalcoholic fatty liver disease and had a positive association with severity. CONCLUSION: HSD17B13 has protective effects on the severity of pediatric nonalcoholic fatty liver disease. Variants of HSD17B13, PARVB, PNPLA3, SAMM50, and TM6SF2 had an additive effect on nonalcoholic fatty liver disease.

Global incidence and prevalence of autoimmune hepatitis, 1970-2022: a systematic review and meta-analysis.

Background: Autoimmune hepatitis (AIH) varies significantly in incidence and prevalence across countries and regions. We aimed to examine global, regional, and national trends in incidence and prevalence of AIH from 1970 to 2022. Methods: We conducted a thorough search of the PubMed/MEDLINE, Embase, CINAHL, Google Scholar, and Cochrane databases from database inception to August 9, 2023, using the search term "autoimmune hepatitis" in combination with "incidence," "prevalence," or "trend." Only general population-based observational studies with larger samples sizes were considered for inclusion. Studies that recruited convenience samples, and those with fewer than 50 participants were excluded. Summary data were extracted from published reports. A random effects model was used and pooled estimates with 95% CI were used to calculate the incidence and prevalence of AIH. Heterogeneity was evaluated using the I2 statistic. The study protocol was registered with PROSPERO, CRD42023430138. Findings: A total of 37 eligible studies, encompassing more than 239 million participants and 55,839 patients with AIH from 18 countries across five continents, were included in the analysis. Global pooled incidence and prevalence of AIH were found to be 1.28 cases per 100,000 inhabitant-years (95% CI, 1.01-1.63, I2 = 99·51%; number of studies, 33; sample population, 220,673,674) and 15.65 cases per 100,000 inhabitants (95% CI, 13.42-18.24, I2 = 99·75%; number of studies, 26; sample population, 217,178,684), respectively. The incidence of AIH was greater in countries with high Human Development Index (>0.92), in North America and Oceania (compared with Asia), among females, adults (compared with children), and high latitude (>45°). Similar patterns in AIH prevalence were observed. Pooled AIH prevalence increased gradually from 1970 to 2019 (1970-1999; 9.95 [4.77-15.13], I2 = 95·58% versus 2015-2022; 27.91 [24.86-30.96], I2 = 99·32%; cases per 100,000 inhabitants). The overall incidence and prevalence of AIH, as well as some subgroup analyses of the studies, displayed asymmetry in the funnel plots, suggesting potential evidence of publication bias. Interpretation: AIH incidence and prevalence have increased significantly and exhibit substantial variation across regions worldwide. Further research is required to assess the incidence and prevalence of AIH, specifically in South America and Africa. Funding: National Research Foundation of Korea.

Catch-Up Growth Pattern in Cleft Palate: A Longitudinal Study from Infancy to Adolescence.

OBJECTIVE: To characterize the patterns of somatic catch-up growth from infancy to adolescence in patients with cleft palate (CP). STUDY DESIGN: We assessed 474 nonsyndromic patients with isolated cleft palate (n = 69) and unilateral and bilateral cleft lip and palate (n = 271; n = 134) who underwent palatoplasty between 1988 and 2017 and had longitudinal physical growth data at birth (T0), cheiloplasty (T1), palatoplasty (T2), childhood (T3), and adolescence (T4). The z scores of weight (ZWT), height (ZHT), and body mass index (ZBMI) were compared among the CP types (isolated cleft palate, unilateral cleft lip and palate, and bilateral cleft lip and palate) and time points (T1, T2, T3, and T4). Subgroup analyses were performed to investigate the growth of patients with malnourishment (z score < -1) at T1 or T2. A generalized linear model was used to investigate the effects of gestational age and cardiac anomalies on the longitudinal changes in ZHT and ZBMI. RESULTS: Regardless of the time point, the overall ZHT, ZWT, and ZBMI approximated 0 in all CP types, indicating few differences from the mean values of noncleft children. Significant catch-up growth occurred in ZHT and ZWT from T1 to T4 for all CP types (all P < .05). Despite the recovery of ZHT and ZBMI in most patients with malnourishment, these values remain relatively low until adolescence. Patients who were born at preterm stage or had surgically repaired cardiac anomalies grew well. CONCLUSIONS: Even in infants with CP and malnutrition, preterm birth, or cardiac anomalies, rapid catch-up growth can occur prior to palatoplasty with the help of comprehensive cleft care.

Public health measures on COVID-19 in North Korea: a quantitative analysis of media programmes in 2020-2022.

OBJECTIVES: Details regarding the management of COVID-19 in North Korea are unknown. The aim of this paper was to analyse media programmes in North Korea in order to understand public health measures and policies concerning COVID-19. SETTING: State-run news agency in North Korea. PRIMARY AND SECONDARY OUTCOME MEASURES: The classification of television programmes on COVID-19 broadcast in a state-run news agency, from January 2020 to May 2022, and public health measures introduced in the programmes. RESULTS: A total of 2671 programmes concerning COVID-19 were included in the study. These programmes provided detailed clinical guidelines to laypeople without medical expertise, including instructions for the usage of medication and preventive measures. An association between the media concern regarding COVID-19 and trade volume, as a proxy of border closure according to the concern of the authorities, provided hints to understand the priorities and aims of the authorities. CONCLUSIONS: The research outcomes provided significant insights into the effort to understand an impaired healthcare system and prevalent drug abuse behaviours in North Korea. Findings from further studies on the recently collected data might suggest additional implications on the North Korean policies on COVID-19.

Clinical and genetic spectrum of GSD type 6 in Korea.

BACKGROUND: Glycogen storage disease type VI (GSD VI) is a rare disease in which liver glycogen metabolism is impaired by mutations in the glycogen phosphorylase L (PYGL). This study aimed to examine the clinical features, genetic analyses, and long-term outcomes of patients with GSD VI in Korea. METHODS: From January 2002 to November 2022, we retrospectively reviewed patients diagnosed with GSD VI using a gene panel at Seoul National University Hospital. We investigated the clinical profile, liver histology, molecular diagnosis, and long-term outcomes of patients with GSD VI. RESULTS: Five patients were included in the study. The age at onset was 18-30 months (median, 21 months), and current age was 3.7-17 years (median, 11 years). All patients showed hepatomegaly, elevated liver transaminase activity, and hypertriglyceridaemia. Hypercholesterolaemia and fasting hypoglycaemia occurred in 60% and 40% of patients, respectively. Ten variants of PYGL were identified, of which six were novel: five missense (p.[Gly607Val], p.[Leu445Pro], p.[Gly695Glu], p.[Val828Gly], p.[Tyr158His]), and one frameshift (p.[Arg67AlafsTer34]). All patients were treated with a high-protein diet, and four also received corn starch. All patients showed improved liver function tests, hypertriglyceridaemia, hepatomegaly, and height z score. CONCLUSIONS: The GSD gene panel is a useful diagnostic tool for confirming the presence of GSD VI. Genetic heterogeneity was observed in all patients with GSD VI. Increased liver enzyme levels, hypertriglyceridaemia, and height z score in patients with GSD VI improved during long-term follow-up.

Global Incidence and Prevalence of Eosinophilic Esophagitis, 1976-2022: A Systematic Review and Meta-analysis.

BACKGROUND AND AIMS: Owing to 2018 expanded diagnostic criteria for eosinophilic esophagitis (EoE) and thus a possible increase in diagnosis, previous studies on the global incidence and prevalence of EoE may need to be updated. We aimed to describe global, regional, and national trends in the incidence and prevalence of EoE from 1976 to 2022 and analyze their associations with geographic, demographic, and social factors through a systematic review. METHODS: We searched the PubMed/MEDLINE, Embase, CINAHL, Google Scholar, and Cochrane databases from their inception dates to December 20, 2022, for studies that reported the incidence or prevalence of EoE in the general population. We calculated the global incidence and prevalence of EoE using pooled estimates with 95% confidence intervals (CIs) and performed subgroup analysis based on age, sex, race, geographical area, World Bank income group, and diagnostic criteria of EoE. RESULTS: Forty studies met the eligibility criteria, including over 288 million participants and 147,668 patients with EoE from 15 countries across the five continents. The global pooled incidence and prevalence of EoE were 5.31 cases per 100,000 inhabitant-years (95% CI, 3.98-6.63; number of studies, 27; sample population, 42,191,506) and 40.04 cases per 100,000 inhabitant-years (95% CI, 31.10-48.98; number of studies, 20; sample population, 30,467,177), respectively. The pooled incidence of EoE was higher in high-income countries (vs low- or middle-income countries), males, and North America (vs Europe and Asia). The global prevalence of EoE followed a similar pattern. The pooled prevalence of EoE gradually increased from 1976 to 2022 (1976-2001; 8.18; 95% CI, 3.67-12.69 vs 2017-2022; 74.42; 95% CI, 39.66-109.19 cases per 100,000 inhabitant-years). CONCLUSIONS: The incidence and prevalence of EoE have increased substantially and vary widely across the world. Further research is needed to evaluate the incidence and prevalence of EoE in Asia, South America, and Africa.

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.

Temporal Trends of the Prevalence of Abdominal Obesity and Metabolic Syndrome in Korean Children and Adolescents between 2007 and 2020.

Background: The prevalence of obesity in children and adolescents is increasing worldwide, which is of concern because obesity can lead to various complications such as metabolic syndrome (MS). Waist circumference (WC) and waist-height ratio (WHtR) are useful indicators of abdominal obesity and MS. In this study, we investigate trends in the prevalence of abdominal obesity and MS using two different references. Methods: Data from the Korea National Health and Nutrition Examination Survey (2007 to 2020) were used. In total, 21,652 participants aged 2 to 18 years and 9,592 participants aged 10 to 18 years were analyzed for abdominal obesity and MS, respectively. The prevalence of abdominal obesity and that of MS were compared using the Korean National Growth Chart in 2007 (REF2007) and the newly published WC and WHtR reference values in 2022 (REF2022). Results: Both WC and WHtR showed an increasing trend. The prevalence of abdominal obesity was 14.71% based on REF2022, 5.85% points higher than that of 8.86% based on REF2007. MS based on REF2022 had a higher prevalence for both the National Cholesterol Education Program definition (3.90% by REF2007, 4.78% by REF2022) and the International Diabetes Federation definition (2.29% by REF2007, 3.10% by REF2022). The prevalence of both abdominal obesity and MS increased over time. Conclusion: The prevalence of abdominal obesity and MS increased in Korean children and adolescents from 2007 to 2020. When analyzed by REF2022, both abdominal obesity and MS showed higher prevalence rates than when using REF2007, indicating that previous reports were underestimated. Follow-up for abdominal obesity and MS using REF2022 is needed.

The Effectiveness and Safety of Methotrexate as the First-Line Immunomodulator of Maintenance Therapy in Pediatric Crohn Disease.

OBJECTIVES: Methotrexate (MTX) has been used as maintenance therapy for Crohn disease (CD) in adults and children. However, there are only a few studies on the MTX's effectiveness in thiopurine-naïve CD adult patients and children. This study aimed to evaluate the MTX's effectiveness and safety as first immunomodulator for maintenance therapy in pediatric CD. METHODS: This retrospective cohort study recruited 64 pediatric CD patients treated with MTX as a first-line immunomodulator. Clinical remission (CR) was assessed at weeks 14, 26, and 52. Mucosal healing (MH) was assessed at weeks 26 and 52. RESULTS: Of 64 patients who received MTX, CR was noted in 60.9% at week 14, 29.7% with MH in 68.0% at week 26, and 27.8% with MH in 81.8% at week 52. When comparing age subtypes according to the Paris classification, the CR rate was higher in A1a than in the other subtypes at week 26 (60.0% in A1a, 26.5% in A1b, 0% in A2; P = 0.038). There were no differences in disease location, behavior, or perianal involvement. Adverse effects were noted in 30 of 64 (46.9%) patients, including 1 patient who stopped MTX before 26 weeks owing to side effects; increased liver enzymes in 25 (39.0%) patients, leukopenia in 5 (7.8%), nausea in 5 (7.8%), skin erosion in 1 (1.6%), and headache in 1 (1.6%). CONCLUSION: MTX as a first-line immunomodulator may be an effective and safe maintenance therapy for pediatric CD patients.

Development and Validation of a Machine Learning-Based Prediction Model for Detection of Biliary Atresia.

Background and Aims: Biliary atresia is a rare and devastating bile duct disease that occurs during the neonatal period. Timely identification and prompt surgical intervention is critical for improving the outcome. The aim of the study was to develop a new machine learning-based prediction model for the detection of biliary atresia. Methods: Neonates aged <100 days with cholestasis at least once were retrospectively screened in 2 tertiary referral hospitals between 2015 and 2020. Simple demographic data, routine laboratory indices, and imaging findings of ultrasonography and hepatobiliary scintigraphy were used as features in the multivariate analysis. The extreme gradient boosting (XGBoost) framework was used to develop prediction models according to the diagnostic steps. Results: Among 1605 enrolled neonates with all-cause cholestasis, 145 (9%) were included as having biliary atresia. Direct bilirubin, gamma-glutamyl transpeptidase, abdominal sonography, and hepatobiliary scan were the most impactful features in prediction models. The Step II XGBoost model, consisting of nonimaging inputs, showed excellent discriminatory performance (area under the curve = 0.97). The Step III and IV XGBoost models showed near-perfect performances (area under the curve = 0.998 and 0.999, respectively). In external validation (n = 912 with 118 [12.9%] biliary atresia), XGBoost-based prediction models consistently showed acceptable performances. Utilizing shapley additive explanation values also provided visualized insight and explanation of the contribution of features in detecting biliary atresia. The models were integrated into a web-based diagnostic tool for case-level application. Conclusion: We introduced a new machine learning-based prediction model for detecting biliary atresia in the largest cohorts of neonatal cholestasis.

Long-Term Survival Outcomes beyond the First Year after Liver Transplantation in Pediatric Acute Liver Failure Compared with Biliary Atresia: A Large-Volume Living Donor Liver Transplantation Single-Center Study.

Pediatric acute liver failure (PALF) is a common cause of liver transplantation (LT) but showed poor post-LT outcomes. We reviewed 36 PALF patients and 120 BA patients who underwent LT in our institution. The cause of PALF was unknown in 66.7%. PALF patients were older (6.2 vs. 2.9 years) with higher PELD scores (31.5 vs. 24.4) and shorter waitlist time (15.7 vs. 256.1 days) (p < 0.01). PALF patients showed higher rates of post-transplant renal replacement therapy (RRT) (13.9% vs. 4.2%) and hepatic artery complications (13.9% vs. 0.8%), while portal vein complications rates were lower (0% vs. 10.8%), (p < 0.05). Although PALF patients showed lower 5-year survival rates (77.8% vs. 95.0 %, p < 0.01), the 5-year survival rates of patients who lived beyond the first year were comparable (96.6% vs. 98.3%, p = 0.516). The most common cause of deaths within one year was graft failure (75.0%) in PALF patients, but infection (67.7%) in BA patients. In multivariate analysis, lower body weight, hepatic artery complications and post-transplant RRT were associated with worse survival outcomes (p < 0.05). In conclusion, physicians should be alert to monitor the immediate postoperative graft dysfunction and hepatic artery complications and patients on post-transplant RRT in order to improve survival outcomes in PALF patients.

Association of Metabolic Signatures with Nonalcoholic Fatty Liver Disease in Pediatric Population.

Several adult omics studies have been conducted to understand the pathophysiology of nonalcoholic fatty liver disease (NAFLD). However, the histological features of children are different from those of adults, and the onset and progression of pediatric NAFLD are not fully understood. In this study, we aimed to evaluate the metabolome profile and metabolic pathway changes associated with pediatric NAFLD to elucidate its pathophysiology and to develop machine learning-based NAFLD diagnostic models. We analyzed the metabolic profiles of healthy control, lean NAFLD, overweight control, and overweight NAFLD groups of children and adolescent participants (N = 165) by assessing plasma samples. Additionally, we constructed diagnostic models by applying three machine learning methods (ElasticNet, random forest, and XGBoost) and multiple logistic regression by using NAFLD-specific metabolic features, genetic variants, and clinical data. We identified 18 NAFLD-specific metabolic features and metabolic changes in lipid, glutathione-related amino acid, and branched-chain amino acid metabolism by comparing the control and NAFLD groups in the overweight pediatric population. Additionally, we successfully developed and cross-validated diagnostic models that showed excellent diagnostic performance (ElasticNet and random forest model: area under the receiver operating characteristic curve, 0.95). Metabolome changes in the plasma of pediatric patients with NAFLD are associated with the pathophysiology of the disease and can be utilized as a less-invasive approach to diagnosing the disease.

Reference Values for Waist Circumference and Waist-Height Ratio in Korean Children and Adolescents.

Background: Abdominal obesity, which is a strong indicator of cardiometabolic risk, is widely evaluated using waist circumference (WC) and waist-height ratio (WHtR). In Korea, the reference values for WC for children and adolescents were published in 2007 and need to be revised. Moreover, there is no reference for WHtR. The aim of this study was to establish new reference values for WC and WHtR in Korean children and adolescents. Methods: Data of 20,033 subjects from the Korea National Health and Nutrition Examination Survey (2007-2019) were used. Tables for reference values and the graphs of smoothed percentile curves of WC and WHtR for children and adolescents aged 2-18 years by sex were generated using the LMS method and locally estimated scatterplot smoothing regression analysis after removing extreme values. Results: Sex-specific reference tables and percentile curves for WC and WHtR were developed. In the new WC curves, the 10th, 50th, and 90th percentile lines were lower than the corresponding lines of the 2007 reference for both sexes. The WHtR curves showed sex-specific differences, although they demonstrated a relative plateau among those aged ≥10 years in both sexes. In the logistic regression analysis, the WC and WHtR z-scores showed higher odds ratios for predicting cardiometabolic risk factors than the body mass index z-score. Conclusion: New WC and WHtR reference values for Korean children and adolescents aged 2-18 years were developed using the latest statistical methods. These references will help monitor and track WC and WHtR for evaluating abdominal obesity among at-risk children and adolescents in Korea.

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.

Effects of PNPLA3, TM6SF2 and SAMM50 on the development and severity of non-alcoholic fatty liver disease in children.

BACKGROUND: Although genetic variants of PNPLA3, TM6SF2 and SAMM50 have been reported to increase the risk of non-alcoholic fatty liver disease (NAFLD), no pediatric studies have evaluated the association between SAMM50 and NAFLD. OBJECTIVE: This study aimed to investigate the risk factors, including genetic variants, of pediatric NAFLD. METHODS: NAFLD was defined as the presence of hepatic steatosis on ultrasound. We included 228 patients with NAFLD (body mass index-Z [BMI-Z] = 2.51 ± 1.01) and 225 controls (BMI-Z = 0.22 ± 1.48). We genotyped four variants of PNPLA3 (rs738409), TM6SF2 (rs58542926) and SAMM50 (rs2073080 and rs3761472) by TaqMan allelic discrimination. The pediatric NAFLD fibrosis score, aspartate transaminase (AST)/platelet ratio index and fibrosis-4 score were used to evaluate the degree of fibrosis. We calculated the genetic risk score for additive effects according to the sum of risk alleles. RESULTS: The mean age was 12.6 ± 3.5 years. The four genetic variants, male sex and BMI-Z, independently increased susceptibility to NAFLD. These four variants, in addition to fasting insulin and triglycerides, remained significant risk factors with higher odds ratios in children with overweight. These variants increased the alanine aminotransferase (ALT) level and three fibrosis scores independently. As the genetic risk score increased, AST, ALT and the fibrosis scores increased independently. CONCLUSION: PNPLA3, TM6SF2 and SAMM50 are associated with the development and severity of pediatric NAFLD. The impact of genetic variants is greater in children with overweight. The four genetic variants have synergetic effects on the severity of pediatric NAFLD.