Epidemiology of pediatric inflammatory bowel disease categorized by age subgroups in Korea.

BACKGROUND: Pediatric inflammatory bowel disease (PIBD) affects different age groups and its incidence is increasing worldwide. However, there is a lack of research focusing on age subgroups in Asian countries. In this nationwide population-based study, we investigated the epidemiology of PIBD among different age subgroups in Korea. METHODS: We analyzed Korean health administration data from 2005 to 2016. Data were divided by age at diagnosis as follows: group 1, 0-1 years; group 2, 2-5 years; group 3, 6-9 years; group 4, 10-16 years. We analyzed the overall incidence, temporal changes, and regional differences by age subgroups, using Poisson regression analysis. RESULTS: From 2005 to 2016, 2734 inflammatory bowel disease (IBD) cases were diagnosed among patients under 17 years of age. In the overall population, the incidence rate of PIBD over the entire study period was 2.248/105 person-years (PY), significantly increasing from 1.173/105 PY in 2005-2007 to 3.267/105 PY in 2014-2016. The incidence rates in groups 1 and 2 remained unchanged, whereas those of groups 3 and 4 increased significantly. The same trend was observed when analyzed separately for Crohn's disease (CD) and ulcerative colitis (UC). The incidence rates of CD in groups 3 and 4 showed differences between metropolitan and non-metropolitan areas, whereas those in groups 1 and 2, and UC of all age subgroups showed no difference. CONCLUSIONS: The temporal trend and regional differences of PIBD differed among age subgroups, suggesting that genetic and environmental factors have varying impacts on IBD development across different subgroups.

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.

PIBF1 regulates trophoblast syncytialization and promotes cardiovascular development.

Proper placental development in early pregnancy ensures a positive outcome later on. The developmental relationship between the placenta and embryonic organs, such as the heart, is crucial for a normal pregnancy. However, the mechanism through which the placenta influences the development of embryonic organs remains unclear. Trophoblasts fuse to form multinucleated syncytiotrophoblasts (SynT), which primarily make up the placental materno-fetal interface. We discovered that endogenous progesterone immunomodulatory binding factor 1 (PIBF1) is vital for trophoblast differentiation and fusion into SynT in humans and mice. PIBF1 facilitates communication between SynT and adjacent vascular cells, promoting vascular network development in the primary placenta. This process affected the early development of the embryonic cardiovascular system in mice. Moreover, in vitro experiments showed that PIBF1 promotes the development of cardiovascular characteristics in heart organoids. Our findings show how SynTs organize the barrier and imply their possible roles in supporting embryogenesis, including cardiovascular development. SynT-derived factors and SynT within the placenta may play critical roles in ensuring proper organogenesis of other organs in the embryo.

Diagnostic accuracy of CT and Doppler US for hepatic outflow obstruction after pediatric liver transplantation using left lobe or left lateral section grafts.

PURPOSE: The aim of this study was to evaluate diagnostic accuracy and to establish computed tomography (CT) and Doppler ultrasonography (US) criteria for hepatic outflow obstruction after pediatric liver transplantation (LT) using left lobe (LL) or left lateral section (LLS) grafts. METHODS: Pediatric patients who underwent LT using LL or LLS grafts between January 1999 and December 2021 were retrospectively included. The diagnostic performance of Doppler US and CT parameters for hepatic outflow obstruction was calculated using receiver operating characteristic (ROC) curve analysis. A diagnostic decision tree model combining the imaging parameters was developed. RESULTS: In total, 288 patients (150 girls; median age at LT, 1.8 years [interquartile range, 0.9 to 3.6 years]) were included. Among the Doppler US parameters, venous pulsatility index (VPI) showed excellent diagnostic performance (area under the ROC curve [AUROC], 0.90; 95% confidence interval [CI], 0.86 to 0.93; Youden cut-off value, 0.40). Among the CT parameters, anastomotic site diameter (AUROC, 0.92; 95% CI, 0.88 to 0.95; Youden cut-off, 4.2 mm) and percentage of anastomotic site stenosis (AUROC, 0.88; 95% CI, 0.84 to 0.92; Youden cut-off, 35%) showed excellent and good diagnostic performance, respectively. A decision tree model combining the VPI, peak systolic velocity, and percentage of anastomotic site stenosis stratified patients according to the risk of hepatic outflow obstruction. CONCLUSION: VPI, anastomotic site diameter, and percentage of anastomotic site stenosis were reliable imaging parameters for diagnosing hepatic outflow obstruction after pediatric LT using LL or LLS grafts.

Correction: Impact of the Coronavirus Disease 2019 Pandemic on Pediatric Gastrointestinal Endoscopy: A Questionnaire-based Internet Survey of 162 Institutional Experiences in Asia Pacific.

[This corrects the article on p. 291 in vol. 26, PMID: 38025493.].

Understanding the molecular mechanism of pathogenic variants of BIR2 domain in XIAP-deficient inflammatory bowel disease.

X-linked inhibitor of apoptosis protein (XIAP) deficiency causes refractory inflammatory bowel disease. The XIAP protein plays a pivotal role in the pro-inflammatory response through the nucleotide-binding oligomerization domain-containing signaling pathway that is important in mucosal homeostasis. We analyzed the molecular mechanism of non-synonymous pathogenic variants (PVs) of XIAP BIR2 domain. We generated N-terminally green fluorescent protein-tagged XIAP constructs of representative non-synonymous PVs. Co-immunoprecipitation and fluorescence cross-correlation spectroscopy showed that wild-type XIAP and RIP2 preferentially interacted in live cells, whereas all non-synonymous PV XIAPs failed to interact properly with RIP2. Structural analysis showed that various structural changes by mutations, such as hydrophobic core collapse, Zn-finger loss, and spatial rearrangement, destabilized the two loop structures (174-182 and 205-215) that critically interact with RIP2. Subsequently, it caused a failure of RIP2 ubiquitination and loss of protein deficiency by the auto-ubiquitination of all XIAP mutants. These findings could enhance our understanding of the role of XIAP mutations in XIAP-deficient inflammatory bowel disease and may benefit future therapeutic strategies.

Successful Use of Bortezomib for Recurrent Progressive Familial Intrahepatic Cholestasis Type II After Liver Transplantation: A Pediatric Case with a 9-Year Follow-Up.

Recurrence of progressive familial intrahepatic cholestasis (PFIC) type II poses challenges during postoperative liver transplant care. Posttransplant patients with PFIC type II risk developing recurrent cholestasis with normal gamma-glutamyl transferase activity, which mimics the original bile salt export pump (BSEP) protein deficiency and is related to a form of immunoglobulin G antibody (anti-BSEP)-mediated rejection. Bortezomib effectively induces apoptosis of actively antibody-producing plasma cells that may have a role in antibody-mediated rejection. In this case, we used bortezomib to treat PFIC type II recurrence after liver transplantation in a child.

A Report on a Nationwide Surveillance System for Pediatric Acute Hepatitis of Unknown Etiology in Korea.

BACKGROUND: Several cases of pediatric acute hepatitis of unknown etiology related to adenoviral infections have been reported in Europe since January 2022. The aim of this study was to compare the incidence, severity, possible etiology, and prognosis of the disease with those in the past in Korea. METHODS: The surveillance group collected data between May and November 2022 using a surveillance system. Acute hepatitis of unknown etiology was defined in patients aged < 16 years with a serum transaminase level > 500 IU/L, not due to hepatitis A-E or other underlying causes. For comparison, data from 18 university hospitals were retrospectively collected as a control group between January 2021 and April 2022. RESULTS: We enrolled 270 patients (mean age, 5 years). The most common symptom was fever. However, the incidence was similar between 2021 and 2022. Liver function test results, number of patients with acute liver failure (ALF), liver transplantation (LT), death, and adenovirus detection rates did not differ between the two groups. None of the adenovirus-positive patients in either group experienced ALF, LT, or death. In the surveillance group, adenovirus-associated virus-2 was detected in four patients, one of whom underwent LT. Patients with an unknown etiology showed significantly higher bilirubin levels, a lower platelet count, and a higher LT rate than patients with a possible etiology. CONCLUSION: The incidence of pediatric acute hepatitis of unknown etiology and adenovirus detection rate have not increased in Korea.

Impact of the Coronavirus Disease 2019 Pandemic on Pediatric Gastrointestinal Endoscopy: A Questionnaire-based Internet Survey of 162 Institutional Experiences in Asia Pacific.

Purpose: The impact of coronavirus 2019 (COVID-19) on gastrointestinal (GI) endoscopy procedures in adults has been reported, with a drastic reduction in the number of procedures. However, there are no sufficient data regarding the impact on pediatric GI endoscopy. Here, we aimed to report that impact in the Asia-Pacific region. Methods: A questionnaire-based internet survey was conducted from June to November 2021 among pediatric endoscopy institutions in the Asia-Pacific region, with each institution providing a single response. Overall, 25 questions focused on the impact of the number of procedures conducted, the usage of personal protective equipment (PPE), and endoscopy training programs during the pandemic. Results: A total of 162 institutions across 13 countries in the Asia-Pacific region participated in the study, and 133 (82.1%) institutions underwent procedure changes since the emergence of COVID-19. The number of esophagogastroduodenoscopy and ileocolonoscopy procedures decreased in 118/133 (88.7%) and 112/133 (84.2%) institutions, respectively. Endoscopy for patient with positive COVID-19 in an emergency or urgent cases still carried out in 102/162 (62.9%) institutions. Screening of COVID-19 for all patients before endoscopy was done across 110/162 (67.9%) institutions. PPE recommendations varied among institutions. Pediatric gastrointestinal endoscopy training programs were discontinued in 127/162 (78.4%) institutions. Conclusion: This study reports the impact of the COVID-19 pandemic on pediatric gastrointestinal endoscopy in the Asia-Pacific region. There has been a significant reduction in the number of endoscopic procedures and relevant training programs.

Disseminated Intravascular Coagulation as a Risk Factor for Clinical Outcome After Liver Transplantation in Pediatric Patients With Kasai Portoenterostomy Failure.

BACKGROUND: Disseminated intravascular coagulation (DIC) is a serious complication in critically ill pediatric patients. This study aimed to evaluate the association between pretransplant DIC and perioperative clinical outcomes of liver transplantation (LT) in pediatric patients with Kasai portoenterostomy (KPE) failure. METHODS: We enrolled pediatric patients who received LT after KPE failure between January 2005 and April 2021. We retrospectively reviewed the electronic medical records of included patients and evaluated the presence of DIC using the International Society on Thrombosis and Hemostasis (ISTH) criteria and association with perioperative clinical outcome. RESULTS: The study included 106 patients. Their median age and body weight at the time of pediatric intensive care unit (PICU) admission were 28.7 months and 9.25 kg, respectively. Of these patients, 23 had undergone pretransplant DIC (22%). Patients with pretransplant DIC required significantly more blood transfusions during operation. They had significantly higher serum lactate levels, pediatric end-stage liver disease scores, pediatric risk for mortality III (PRISM III) scores, longer durations of mechanical ventilator support, and longer PICU stays (all P < .05). CONCLUSIONS: The presence of pretransplant DIC in pediatric patients requiring LT after KPE failure was associated with poor clinical outcomes, which required more intensive and meticulous supportive management in the perioperative period of LT. DIC would be a promising prognostic factor in these patients.

Modified patch-conduit venoplasty for portal vein hypoplasia in pediatric liver transplantation.

Background: Portal vein (PV) interposition can induce various PV-related complications, making more reliable techniques necessary. The present study describes the development of a modified patch venoplasty technique, combining the native PV wall and a vein homograft conduit, called modified patch-conduit venoplasty (MPCV). Methods: The surgical technique for MPCV was optimized by simulation and applied to seven pediatric patients undergoing liver transplantation (LT) for biliary atresia combined with PV hypoplasia. Results: The simulation study revealed that inserting the whole-length native PV wall as a longitudinal rectangular patch was more effective in preventing PV conduit stenosis than the conventional technique using triangular partial insertion. These findings were used to develop the MPCV technique, in which the native PV wall was converted into a long rectangular patch, acting as a backbone for PV reconstruction. A longitudinal incision on the vein conduit converted the cylindrical vein into a large vein patch. The wall of the native PV was fully preserved as the posterior wall of the PV conduit, thus preventing longitudinal redundancy and unwanted rotation of the reconstructed PV. This technique was applied to seven patients with biliary atresia undergoing living-donor and deceased-donor split LT. None of these patients has experienced PV complications for up to 12 months after transplantation. Conclusions: This newly devised MCPV technique can replace conventional PV interposition. MCPV may be a surgical option for reliable PV reconstruction using fresh or cryopreserved vein homografts during pediatric LT.

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.

[Postoperative Imaging Findings of Biliary Atresia]. / 담도폐쇄증의 ìˆ˜ìˆ í›„ 영상 소견.

The Kasai portoenterostomy is the first-line treatment for the restoration of the flow of bile to the small intestine in patients with biliary atresia. Various complications can occur after Kasai portoenterostomy, including ascending cholangitis, biliary cirrhosis, and portal hypertension. Of these potential complications, ascending cholangitis in the most common. In cases of patients having uncontrolled complications due to progressive liver cirrhosis, portal hypertension, or progressive hyperbilirubinemia, liver transplantation is the indicated as treatment plan. Lifelong follow-up, particularly involving imaging studies, is important for the identification of various complications arising from biliary atresia after Kasai portoenterostomy. Additionally, imaging studies play a crucial role in the evaluation of potential liver donors and recipients. US is a key imaging modality utilized in the management of patients who undergo Kasai portoenterostomy, while CT and MRI are imperative to obtaining an accurate diagnosis.

Pediatric living donor liver transplantation for biliary embryonal rhabdomyosarcoma: a case report of a case showing disease-free survival over 2 years.

Biliary rhabdomyosarcoma is a rare tumor, but it is still the most common tumor of the biliary tract in children. We report a case of a 6-year-old boy with biliary embryonal rhabdomyosarcoma and liver metastasis, which were treated with neoadjuvant and adjuvant chemotherapy combined with living donor liver transplantation (LDLT). Initial imaging studies showed a low-attenuation intraductal mass from the left hepatic duct to the intrapancreatic common bile duct with diffuse upstream dilatation of the intrahepatic duct and liver metastasis. Endoscopic biopsy revealed embryonal rhabdomyosarcoma. After tumor size reduction through neoadjuvant chemotherapy, LDLT was planned to remove the tumor completely. A left lateral section graft weighing 330 g was harvested from his 38-year-old mother and the graft-to-recipient weight ratio was 1.94%. Routine pediatric LDLT operation was performed with deep excavation of intrapancreatic distal bile duct. The explant liver showed minimal residual embryonal rhabdomyosarcoma with no lymph node metastasis. The patient recovered uneventfully from LDLT operation. Scheduled adjuvant chemotherapy was performed for 6 months. The patient is doing well without any evidence of tumor recurrence for 26 months after LDLT. In conclusion, liver transplantation could be an effective treatment for unresectable biliary rhabdomyosarcoma in children according to the location of tumor.

Accuracy of attenuation imaging in the assessment of pediatric hepatic steatosis: correlation with the controlled attenuation parameter.

PURPOSE: This study evaluated the accuracy of attenuation imaging (ATI) for the assessment of hepatic steatosis in pediatric patients, in comparison with the FibroScan vibration-controlled transient elastography controlled attenuation parameter (CAP). METHODS: Consecutive pediatric patients referred for evaluation of obesity who underwent both ATI and FibroScan between February 2020 and September 2021 were included. The correlation between attenuation coefficient (AC) and CAP values was assessed using the Spearman test. The AC cutoff value for discriminating hepatic steatosis corresponding to a CAP value of 241 dB/m was calculated. Multivariable linear regression analysis was performed to estimate the strength of the association between AC and CAP. The diagnostic accuracy of AC cutoffs was estimated using the imperfect gold-standard methodology based on a two-level Bayesian latent class model. RESULTS: Seventy patients (median age, 12.5 years; interquartile range, 11.0 to 14.0 years; male:female, 58:12) were included. AC and CAP showed a moderate-to-good correlation (ρ =0.646, P<0.001). Multivariable regression analysis affirmed the significant association between AC and CAP (P<0.001). The correlation was not evident in patients with a body mass index ≥30 kg/m2 (ρ=-0.202, P=0.551). Linear regression revealed that an AC cutoff of 0.66 dB/cm/MHz corresponded to a CAP of 241 dB/m (sensitivity, 0.93; 95% confidence interval [CI], 0.85 to 0.98 and specificity, 0.87; 95% CI, 0.56 to 1.00). CONCLUSION: ATI showed an acceptable correlation with CAP values in a pediatric population, especially in patients with a body mass index <30 kg/m2. An AC cutoff of 0.66 dB/cm/MHz, corresponding to a CAP of 241 dB/m, can accurately diagnose hepatic steatosis.

Living donor liver transplantation in an infant patient with progressive familial intrahepatic cholestasis along with hepatocellular carcinoma: a case report.

Progressive familial intrahepatic cholestasis (PFIC) is an autosomal recessive inherited disease requiring liver transplantation (LT). Hepatocellular carcinoma (HCC) is very rare in infants. We present a case of living donor LT using a left lateral section graft performed in a 7-month-old female infant diagnosed with PFIC type II and HCC. No mutation on ABCB11 gene was identified. Because of progressive deterioration of liver function, living donor LT with her mother's left lateral section graft was performed. Pretransplant serum alpha-fetoprotein (AFP) level was increased to 2,740 ng/mL, but HCC was not taken into account because of its rarity. The explant liver showed micronodular liver cirrhosis, multiple infantile hemangiomas and two HCCs of 0.7 cm and 0.3 cm in size. The patient recovered uneventfully from the LT operation. This patient has been regularly followed up with abdomen ultrasonography and AFP measurement every 6 months. The patient has been continually doing well for 8 years after the LT. In conclusion, LT is currently the only effective treatment for PFIC-associated end-stage liver diseases. HCC can develop at the cirrhotic liver of any cause, thus elevation of HCC tumor markers in pediatric patients is an important clue to perform further investigation before LT.

Assessment of pathogens and risk factors associated with bloodstream infection in the year after pediatric liver transplantation.

BACKGROUND: Bloodstream infection (BSI) is one of the most significantly adverse events that can occur after liver transplantation (LT) in children. AIM: To analyze the profile of BSI according to the postoperative periods and assess the risk factors after pediatric LT. METHODS: Clinical data, collected from medical charts of children (n = 378) who underwent primary LT, were retrospectively reviewed. The primary outcome considered was BSI in the first year after LT. Univariate and multivariate analyses were performed to identify risk factors for BSI and respective odds ratios (ORs). RESULTS: Of the examined patients, 106 (28%) experienced 162 episodes of pathogen-confirmed BSI during the first year after LT. There were 1.53 ± 0.95 episodes per children (mean ± SD) among BSI-complicated patients with a median onset of 0.4 mo post-LT. The most common pathogenic organisms identified were Coagulase-negative staphylococci, followed by Enterococcus spp. and Streptococcus spp. About half (53%) of the BSIs were of unknown origin. Multivariate analysis demonstrated that young age (≤ 1.3 year; OR = 2.1, P = 0.011), growth failure (OR = 2.1, P = 0.045), liver support system (OR = 4.2, P = 0.008), and hospital stay of > 44 d (OR = 2.3, P = 0.002) were independently associated with BSI in the year after LT. CONCLUSION: BSI was frequently observed in patients after pediatric LT, affecting survival outcomes. The profile of BSI may inform clinical treatment and management in high-risk children after LT.

Clinical characteristics of neonatal cholestasis in a tertiary hospital and the development of a novel prediction model for mortality.

BACKGROUND: Few studies have described the aetiologies of neonatal cholestasis, and the overall neonatal cholestasis-related mortality (NCM) rate is unclear. We investigated the aetiology and outcome of neonatal cholestasis in a tertiary hospital and developed an NCM prediction model for these patients. METHODS: Patients aged <100 days with serum direct bilirubin (DB) levels of >1.0 mg/dL were retrospectively screened. Diagnostic and laboratory data during the 8-week follow-up period after enrolment between 2005 and 2020 were extracted digitally, and medical charts were reviewed manually by clinicians. Logistic regression was used to derive a prediction model for the 1-year mortality outcome of neonatal cholestasis, and performance evaluation and external validation were conducted for the NCM prediction model. FINDINGS: We enrolled 4028 neonates with DB of >1.0 mg/dL at least once. Prematurity and birth injury (35.4%), complex heart anomalies (18.6%), liver diseases (11.4%), and gastrointestinal anomalies (9.2%) were the most common aetiologies; 398 (9.9%) patients died before one year of age. The peak value of DB was positively correlated to the 1-year mortality rate. In the multivariate analysis, simple laboratory indices, including platelet, prothrombin time, aspartate aminotransferase, albumin, direct bilirubin, creatinine, and C-reactive protein, were independent predictors of 1-year mortality outcome of complete-case subjects. Using these laboratory indices, a logistic regression-based NCM prediction model was constructed. It showed acceptable performances on discrimination (area under the curve, 0.916), calibration (slope, 1.04) and Brier scoring (0.072). The external validation of the sample (n = 920) from two other centres also revealed similar performance profiles of the NCM model. INTERPRETATION: Various aetiologies of neonatal cholestasis were identified in a tertiary hospital, resulting in unfavourable outcomes of a large proportion. The NCM prediction model may have the potential to help clinicians to be aware of high-risk neonatal cholestasis. FUNDING: Ministry of Health & Welfare, Republic of Korea.

Shift to a Younger Age and Regional Differences in Inflammatory Bowel Disease in Korea: Using Healthcare Administrative Data.

BACKGROUND: Research using healthcare administrative data with a validated algorithm can reveal the real-world data of rare diseases. AIMS: We investigated an accurate algorithm for detecting incident cases of inflammatory bowel disease (IBD) from healthcare data and analyzed the nationwide population-based epidemiological features in Korea. METHODS: Healthcare data from Songpa-Kangdong districts in Seoul were extracted from the National Health Insurance Service and analyzed to identify the best algorithm reflecting the cohort data. The most accurate criterion was applied to the entire database for further analysis. RESULTS: With the selected working criteria, 37,555 incident cases of IBD (Crohn's Disease [CD], 13,130; ulcerative colitis [UC], 24,425) were identified from 2005 to 2016. The male-to-female ratio was 2.5:1 for CD and 1.4:1 for UC. Over 12 years, the annual standardized incidence rate (SIR) per 100,000 people increased from 1.6 to 2.7 and 3.8 to 4.3 for CD and UC, respectively. The peak age at diagnosis of UC shifted from 55-59 years to 20-24 years, whereas that of CD shifted from 19 to 17 years. The SIR of CD was higher in metropolitan areas than in non-metropolitan areas. CONCLUSIONS: This nationwide population-based epidemiologic study of Korean IBD revealed a gradual increase in the incidence rates and a notable shift toward younger age at diagnosis. Males were predominant in both CD and UC. There was an urban-rural difference in the SIR of CD.

Gestational alloimmune liver disease treated with exchange transfusion and intravenous immunoglobulin: A case study.

Gestational alloimmune liver disease (GALD) is a materno-fetal alloimmune disorder that targets the fetal liver and often causes neonatal liver failure. GALD most commonly presents as neonatal hemochromatosis (NH), which is a severe neonatal liver injury confirmed by extra-hepatic iron accumulation at various sites. With the discovery of the alloimmune mechanism of GALD, exchange transfusion and intravenous immunoglobulin (IVIG) administration are being used as novel treatments. Here, we present a rare case of an 11-day-old female infant who presented with marked hyperbilirubinemia. Laboratory findings showed significantly elevated direct and indirect bilirubin, high ferritin and alpha fetoprotein levels, high transferrin saturation, and severe coagulopathy. Abdominal magnetic resonance imaging revealed markedly reduced T2 signal intensity in the liver and pancreas compared to the spleen, suggesting iron deposition. The infant was diagnosed with NH and successfully treated with exchange transfusion and four doses of IVIG.