A Nationwide Survey on Gastrointestinal Endoscopy Practice Patterns among Pediatric Endoscopists in South Korea / 대한소아소화기영양학회지

Purpose@#Gastrointestinal (GI) endoscopy is an important tool for diagnosing and treating GI diseases in children. This study aimed to analyze the current GI endoscopy practice patterns among South Korean pediatric endoscopists. @*Methods@#Twelve members of the Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition developed a questionnaire. The questionnaire was emailed to pediatric gastroenterologists attending general and tertiary hospitals in South Korea. @*Results@#The response rate was 86.7% (52/60), and 49 of the respondents (94.2%) were currently performing endoscopy. All respondents were performing esophagogastroduodenoscopy, and 43 (87.8%) were performing colonoscopy. Relatively rare procedures for children, such as double-balloon enteroscopy (DBE) (4.1%), endoscopic retrograde cholangiopancreatography (ERCP) (2.0%), and endoscopic ultrasound (EUS) (2.0%), were only performed by pediatric gastroenterologists at very few centers, but were performed by adult endoscopists in most of the centers; of all the respondents, 83.7% (41/49) performed emergency endoscopy. In most centers, the majority of the endoscopies were performed under sedation, with midazolam (100.0%) and ketamine (67.3%) as the most frequently used sedatives. @*Conclusion@#While most pediatric GI endoscopists perform common GI endoscopic procedures, rare procedures, such as DBE, ERCP, and EUS, are only performed by pediatric gastroenterologists at very few centers, and by adult GI endoscopists at most of the centers. For such rare procedures, close communication and cooperation with adult GI endoscopists are required.

Practice Patterns of Colorectal Polypectomy in Pediatric Endoscopic Specialists in South Korea: A Nationwide Survey Study / 대한소아소화기영양학회지

Purpose@#Total colonoscopy is recommended if colorectal polyps are clinically suspected.This study aimed to investigate the performance status of pediatric colonoscopic polypectomy in Korea. @*Methods@#We surveyed pediatric endoscopic specialists who perform colonoscopic polypectomy in Korea using a questionnaire of 13 questions on pediatric colonoscopic polypectomy performance status. @*Results@#The survey was conducted at 45 institutions, and 32 specialists (71.1%) responded.Among the respondents, 31.2% (10/32) said colonoscopy was performed in all age groups, while 12.5% (4/32) said sigmoidoscopy was performed in all age groups. Meanwhile, 56.2% (18/32) said that sigmoidoscopy was performed in young children, while colonoscopy was performed in older children. Among them, 38.9% (7/18) believe that 4–6 years were young, and 44.5% (8/18) believe that 7–9 years were young. Regarding surveillance examinations, 21.9% (7/32) said they would perform a surveillance colonoscopy or sigmoidoscopy in the future if less than five juvenile polyps were found in the colon. Meanwhile, if less than five adenomatous polyps were found in the colon, 93.8% (30/32) said they would perform surveillance colonoscopy or sigmoidoscopy in the future. @*Conclusion@#More than half of the pediatric endoscopic specialists in Korea choose between a colonoscopy and sigmoidoscopy depending on the patient’s age, contrary to the generally accepted recommendation of total colonoscopy if colorectal polyps are suspected in children and adolescents. In this survey, most pediatric endoscopists used the age range of 4–9 years as the reference age.

Fecal Calprotectin Levels Significantly Correlate with Polyp Size in Children and Adolescents with Juvenile Colorectal Polyps / 대한소아소화기영양학회지

Purpose@#We aimed to investigate factors that correlate with fecal calprotectin (FC) levels in children and adolescents with colorectal polyps. @*Methods@#Pediatric patients aged <19 years who underwent colonoscopic polypectomy for a juvenile polyps (JPs) and FC tests were simultaneously conducted in a multicenter, retrospective study. Baseline demographics, colonoscopic and histological findings, and laboratory tests, including FC levels, were investigated. Correlations between the factors were investigated, and linear regression analysis revealed factors that correlated with FC levels. FC levels measured after polypectomies were investigated and the FC levels pre- and post-polypectomies were compared. @*Results@#A total of 33 patients were included in the study. According to Pearson correlation analysis, the polyp size was the only factor that showed a statistically significant correlation with FC levels (r=0.75, p<0.001). Furthermore, according to the multivariate linear regression analysis, polyp size was the only factor that showed a statistically significant correlation with FC levels (adjusted R2=0.5718, β=73.62, p<0.001). The median FC level was 400 mg/ kg (interquartile range [IQR], 141.6–1,000 mg/kg), and the median polyp size was 14 mm (IQR, 9–20 mm). Nineteen patients underwent post-polypectomy FC tests. FC levels showed a significant decrease after polypectomy from a median of 445.2 mg/kg (IQR, 225–1,000) to 26.5 mg/kg (11.5–51) ( p<0.001). @*Conclusion@#FC levels significantly correlated with polyp size in children and adolescents with JPs.

Associations of Polyp Characteristics in Children and Adolescents Presenting with Less Than Five Colorectal Polyps: A Full Colonoscopy Is Still Required

Background/Aims@#A full colonoscopy is currently required in children and adolescents with colorectal polyps, because of their potential of neoplastic transformation and complications such as intussusception. We aimed to analyze the associations of polyp characteristics in children and adolescents with colorectal polyps. Based on these findings, we also aimed to reevaluate the necessity of conducting a full colonoscopy. @*Methods@#Pediatric patients <18 years of age who had undergone a colonoscopic polypectomy and those with <5 colorectal polyps were included in this multicenter, retrospective study. Baseline clinicodemographics, colonoscopic and histologic findings were investigated. @*Results@#A total of 91 patients were included. Multivariate logistic regression analysis showed that polyp size was the only factor associated with the presence of any polyps located proximal to the splenic flexure (odds ratio [OR], 2.25; 95% confidence interval [CI], 1.28 to 4.28; p=0.007). Furthermore, polyp location proximal to the splenic flexure and sessile morphology were associated with the presence of any adenomatous polyp (OR, 8.51; 95% CI, 1.43 to 68.65; p=0.023; OR, 18.41; 95% CI, 3.45 to 173.81; p=0.002, respectively). @*Conclusions@#In children and adolescents presenting with <5 colorectal polyps, polyp size and the presence of any adenomatous polyp were positively associated with polyp location proximal to the splenic flexure. This finding supports the necessity of a full colonoscopic exam in pediatric patients with colorectal polyps for the detection of polyps before the occurrence of complications such as intussusception or neoplastic transformation.

Cardiac Complications Associated with Eating Disorders in Children:A Multicenter Retrospective Study / 대한소아소화기영양학회지

Purpose@#Eating disorders often result in somatic complications, including cardiac abnormalities. Cardiac abnormalities may involve any part of the heart, including the cardiac conduction system, and can lead to sudden cardiac death. The current study aimed to evaluate the incidence of cardiac complications in pediatric patients with eating disorders and their associated factors. @*Methods@#We retrospectively analyzed patients aged 10–18 years who were diagnosed with DSM-V (Diagnostic and Statistical Manual of Mental Disorder-V) eating disorders and underwent electrocardiography (ECG) and/or echocardiography between January 2015 and May 2020. @*Results@#In total, 127 patients were included, of whom 113 (89.0%) were female. The median body mass index (BMI) was 15.05±3.69 kg/m2 . Overall, 74 patients (58.3%) had ECG abnormalities, with sinus bradycardia being the most common abnormality (91.9%). Patients with ECG abnormalities had significantly lower BMI (14.35±2.78 kg/m2 vs. 16.06± 4.55 kg/m2 , p<0.001) than patients without ECG abnormalities, as well as lower phosphorus and higher cholesterol levels. Among the 46 patients who underwent echocardiographic evaluation, 23 (50.0%) had echocardiographic abnormalities, with pericardial effusion being the most common (60.9%). The median left ventricular mass (LVM) and ejection fraction were 67.97±21.25 g and 66.91±28.76%, respectively. LVM and BMI showed a positive correlation (r=0.604, p<0.001). After weight gain, the amount of pericardial effusion was reduced in 3 patients, and 30 patients presented with normal ECG findings. @*Conclusion@#Cardiac abnormalities are relatively frequent in patients with eating disorders.Physicians should focus on this somatic complication and careful monitoring is required.

Association between Fecal Calprotectin and Mucosal Healing in Pediatric Patients with Crohn’s Disease Who Have Achieved Sustained Clinical Remission with Anti-Tumor Necrosis Factor Agents

Background/Aims@#Although mucosal healing (MH) is acknowledged as the treatment target in the treat-to-target era, there are limitations on repeated endoscopic examinations, especially in pediatric patients. We aimed to investigate whether fecal calprotectin (FC) could serve as a surrogate marker for the assessment of MH in pediatric patients with Crohn’s disease (CD) who have achieved sustained clinical remission (CR) while treated with anti-tumor necrosis factor (TNF) agents. @*Methods@#This multicenter retrospective cross-sectional study included pediatric CD patients who had sustained a CR for at least 6 months with anti-TNF agents and who simultaneously underwent ileocolonoscopy and FC tests during follow-up. MH was defined as the absence of any ulcer on ileocolonoscopy. @*Results@#A total of 131 patients were included in this study. MH was observed in 87 patients (66.7%). The FC level was significantly lower in patients with MH than in those without MH (median 49.0 mg/kg vs 599.0 mg/kg; p<0.001). According to the multivariate logistic regression analysis, FC was the only factor associated with MH (odds ratio, 0.62; 95% confidence interval [CI], 0.52 to 0.73; p<0.001). According to the receiver operating characteristic curve analysis, the optimal cutoff value for FC for the association with MH was <140 mg/kg (area under the curve 0.890, 95% CI 0.829 to 0.951, sensitivity 78.2%, specificity 88.6%, p<0.001). @*Conclusions@#FC was associated with MH in pediatric patients with CD who had achieved a sustained CR for at least 6 months with anti-TNF agents. In these patients, FC can be used to stratify patients and guide decisions regarding ileocolonoscopy in the treat-to-target era.

Potential Utility of Fecal Calprotectin in Discriminating Colorectal Polyps From Other Major Etiologies in Children Presenting With Isolated Hematochezia

Background@#Colorectal polyps are the most common cause of isolated hematochezia in children, which requires a colonoscopy for diagnosis. We aimed to investigate the potential utility of fecal calprotectin (FC) in assessing colorectal polyps detected by colonoscopy among children presenting with isolated hematochezia. @*Methods@#Pediatric patients of the age of < 18 years who had undergone both colonoscopy and FC tests for isolated hematochezia from June 2016 to May 2020 were included in the present multicenter, retrospective, cross-sectional study. Comparative analysis was conducted between major causes of isolated hematochezia and FC cut-offs for discriminating colorectal polyps were explored. @*Results@#A total 127 patients were included. Thirty-five patients (27.6%) had colorectal polyps, followed by anal fissure (14.2%), ulcerative colitis (UC; 12.6%), and others. A significant difference in FC levels was observed between patients with colorectal polyps (median, 278.7 mg/kg), anal fissures (median, 42.2 mg/kg), and UC (median, 981 mg/ kg) (P < 0.001). According to receiver operating characteristic curve analysis, among patients diagnosed with colorectal polyp or anal fissure, the most accurate FC cut-off for discriminating colorectal polyps from anal fissures on colonoscopy was 225 mg/kg (sensitivity, 59.4%; specificity, 94.4%; positive predictive value [PPV], 95.0%; negativepredictive value [NPV], 56.7%; area under the curve [AUC], 0.8; 95% confidence interval [CI], 0.678–0.923; P < 0.001), while among patients diagnosed with colorectal polyp or UC, the most accurate FC cut-off for discriminating colorectal polyps from UC on colonoscopy was 879 mg/kg (sensitivity, 81.2%; specificity, 56.2%; PPV, 78.8%; NPV, 60.0%; AUC, 0.687; 95% CI, 0.521–0.852; P < 0.001). @*Conclusion@#FC may assist in assessing the cause of lower gastrointestinal tract bleeding in children who present with isolated hematochezia.

Infliximab Therapy for Children with Moderate to Severe Ulcerative Colitis:A Step-Up versus a Top-Down Strategy

Purpose@#We aimed to investigate clinical outcomes between top-down (TD) and conventional step-up (SU) therapies in pediatric patients with moderate to severe ulcerative colitis (UC). @*Materials and Methods@#All patients underwent clinical and endoscopic evaluation at diagnosis and 4 months and 1 year after treatment. Patients who started treatment with corticosteroid were grouped in the SU group, while those that initiated early infliximab (IFX) were grouped in the TD group. Among the SU group, patients who eventually changed to IFX treatment due to steroid resistance or dependency were included in the SU(R) group. @*Results@#In total, 44 children with moderate to severe UC were included for analysis. Twenty-one patients were included in the SU group, 23 were included in the TD group, and 10 were enrolled in the SU(R) group. Relapse rates were 47.6% (10/21) in the SU group and 17.4% (4/23) in the TD group (p=0.033). Among relapsed patients, the durations from remission to relapse were 17.3 months (0.9–46.9) in the SU group and 24.3 months (1.8–44.9) in the TD group. There was no statistically significant difference in the sustained durations of remission after IFX administration between the SU(R) and TD groups [3.9 (1.4–6.3) and 2.3 (0.3–5.2) years, respectively (p>0.05)]. @*Conclusion@#According to our study, early use of IFX without corticosteroid treatment for children with moderate to severe UC helps to lower relapse rates. We also found that IFX was a very effective treatment for pediatric UC, with a sustained duration of remission similar between TD and SU(R) groups.

Nationwide “Pediatric Nutrition Day” survey on the nutritional status of hospitalized children in South Korea

BACKGROUND/OBJECTIVES@#To evaluate the nutritional status and prevalence of malnutrition in hospitalized children at admission and during hospitalization in South Korea. @*SUBJECTS/METHODS@#This first cross-sectional nationwide “Pediatric Nutrition Day (pNday)” survey was conducted among 872 hospitalized children (504 boys, 368 girls; 686 medical, 186 surgical) from 23 hospitals in South Korea. Malnutrition risk was screened using the Pediatric Yorkhill Malnutrition Score (PYMS) and the Screening Tool Risk on Nutritional status and Growth. Nutritional status was assessed by z-scores of weight-for-age for underweight, weight-for-height for wasting, and height-for-age for stunting as well as laboratory tests. @*RESULTS@#At admission, of the 872 hospitalized children, 17.2% were underweight, and the prevalence of wasting and stunting was 20.2% and 17.3%, respectively. During hospitalization till pNday, 10.8% and 19.6% experienced weight loss and decreased oral intake, respectively.During the aforementioned period, fasting was more prevalent in surgical patients (7.5%) than in medical patients (1.6%) (P < 0.001). According to the PYMS, 34.3% and 30% of the children at admission and on pNday, respectively, had a high-risk of malnutrition, requiring consultation with the nutritional support team (NST). However, only 4% were actually referred to the NST during hospitalization. @*CONCLUSIONS@#Malnutrition was prevalent at admission and during hospitalization in pediatric patients, with many children experiencing weight loss and poor oral intake. To improve the nutritional status of hospitalized children, it is important to screen and identify all children at risk of malnutrition and refer malnourished patients to the multidisciplinary NST for proper nutritional interventions.

Incidentally Detected Asymptomatic Perianal Abscess in an Adolescent during Crohn's Disease Diagnosis: Is Routine Pelvic Imaging Required in Korean Pediatric Patients at Diagnosis? / 대한소아소화기영양학회지

Perianal fistulizing diseases, namely perianal fistulas and/or abscesses, are well-known complications of Crohn's disease (CD). These are known to develop more frequently in Asian children with CD, especially in the early stages of the disease course. Approximately half of the pediatric CD cases in Korea present with perianal fistulizing diseases at diagnosis. We report a rare case of a 12-year-old boy with CD with an incidental discovery of a perianal abscess on pelvic magnetic resonance imaging during CD diagnosis. No symptoms or signs of perianal fistulizing disease were identified. The early diagnosis of the perianal abscess enabled timely and effective treatment. Considering the high incidence of concomitant perianal CD in Korean children at diagnosis, perianal imaging may be useful and should be considered during diagnostic evaluation, even in patients with no subjective or objective findings indicating perianal CD.

Severe Disease Activity Based on the Paris Classification Is Associated with the Development of Extraintestinal Manifestations in Korean Children and Adolescents with Ulcerative Colitis

Background@#There are limited data regarding the extraintestinal manifestations (EIMs) associated with pediatric inflammatory bowel disease (IBD) in Korea. We aimed to investigate the clinical features and factors associated with the development of EIMs in Korean children and adolescents with IBD. @*Methods@#This multicenter, retrospective study was conducted from 2010 to 2017. Baseline clinicodemographic, laboratory findings, disease activity, disease phenotypes, and EIMs were investigated. @*Results@#A total of 172 patients were included. One-hundred thirty-seven (79.7%) had Crohn's disease (CD), and 35 (20.3%) had ulcerative colitis (UC). EIMs occurred in 42 patients (24.4%). EIMs developed in 34/137 diagnosed with CD (24.8%), and in 8/35 diagnosed with UC (22.9%), during a median follow-up duration of 3.2 (interquartile range, 1.9–5.4) years for CD and 3.0 (1.0–4.0) years for UC, respectively. Arthritis/arthralgia was most commonly observed (n = 15, 35.7%), followed by stomatitis/oral ulcer (n = 10, 23.8%), hepatitis (n = 5, 11.9%), nephritis (n = 4, 9.5%), pancreatitis (n = 2, 4.8%), erythema nodosum (n = 2, 4.8%), pyoderma gangrenosum (n = 1, 2.4%), primary sclerosing cholangitis (n = 1, 2.4%), uveitis (n = 1, 2.4%), and ankylosing spondylitis (n = 1, 2.4%). A significant difference in disease severity based on the Paris classification (P = 0.011) and ESR at diagnosis (P = 0.043) was observed between the EIM positive and negative group in patients with UC. According to logistic regression analyses, S1 disease severity based on the Paris classification was the only factor that was significantly associated with the development of EIMs (odds ratio, 16.57; 95% confidence interval, 2.18–287.39; P = 0.017). @*Conclusion@#Severe disease activity based on the Paris classification in pediatric patients with UC was significantly associated with EIM development. As disease severity in the Paris classification is a dynamic parameter, treatment should be focused on disease control to minimize the occurrence of EIMs in Korean children and adolescents with UC.

Procedural Sedation for Pediatric Upper Gastrointestinal Endoscopy in Korea

Background@#Sedative upper endoscopy is similar in pediatrics and adults, but it is characteristically more likely to lead to respiratory failure. Although recommended guidelines for pediatric procedural sedation are available within South Korea and internationally, Korean pediatric endoscopists use different drugs, either alone or in combination, in practice. Efforts are being made to minimize the risk of sedation while avoiding procedural challenges. The purpose of this study was to collect and analyze data on the sedation methods used by Korean pediatric endoscopists to help physicians perform pediatric sedative upper endoscopy (PSUE). @*Methods@#The PSUE procedures performed in 15 Korean pediatric gastrointestinal endoscopic units within a year were analyzed. Drugs used for sedation were grouped according to the method of use, and the depth of sedation was evaluated based on the Ramsay scores. The procedures and their complications were also assessed. @*Results@#In total, 734 patients who underwent PSUE were included. Sedation and monitoring were performed by an anesthesiologist at one of the institutions. The sedative procedures were performed by a pediatric endoscopist at the other 14 institutions. Regarding the number of assistants present during the procedures, 36.6% of procedures had one assistant, 38.8%had 2 assistants, and 24.5% had 3 assistants. The average age of the patients was 11.6 years old. Of the patients, 19.8% had underlying diseases, 10.0% were taking medications such as epilepsy drugs, and 1.0% had snoring or sleep apnea history. The average duration of the procedures was 5.2 minutes. The subjects were divided into 5 groups as follows: 1) midazolam + propofol + ketamine (M + P + K): n = 18, average dose of 0.03 + 2.4 + 0.5 mg/kg;2) M + P: n = 206, average dose of 0.06 + 2.1 mg/kg; 3) M + K: n = 267, average dose of 0.09 + 0.69 mg/kg; 4) continuous P infusion for 20 minutes: n = 15, average dose of 6.6 mg/kg; 5) M: n = 228, average dose of 0.11 mg/kg. The average Ramsay score for the five groups was 3.7, with significant differences between the groups (P < 0.001). Regarding the adverse effects, desaturation and increased oxygen supply were most prevalent in the M + K group. Decreases and increases in blood pressure were most prevalent in the M + P + K group, and bag-mask ventilation was most used in the M + K group. There were no reported incidents of intubation or cardiopulmonary resuscitation. A decrease in oxygen saturation was observed in 37 of 734 patients, and it significantly increased in young patients (P = 0.001) and when ketamine was used (P = 0.014). Oxygen saturation was also correlated with dosage (P = 0.037). The use of ketamine (P < 0.001) and propofol (P < 0.001) were identified as factors affecting the Ramsay score in the logistic regression analysis. @*Conclusion@#Although the drug use by Korean pediatric endoscopists followed the recommended guidelines to an extent, it was apparent that they combined the drugs or reduced the doses depending on the patient characteristics to reduce the likelihood of respiratory failure. Inducing deep sedation facilitates comfort during the procedure, but it also leads to a higher risk of complications.

Severe Phenotype of Non-alcoholic Fatty Liver Disease in Pediatric Patients with Subclinical Hypothyroidism: a Retrospective Multicenter Study from Korea

Background@#It is uncertain whether non-alcoholic fatty liver disease (NAFLD) is associated with subclinical hypothyroidism (SH) in pediatric patients. The purpose of this study was to investigated the prevalence and related factors of SH in pediatric patients with NAFLD. We also evaluate the association between liver fibrosis and SH. @*Methods@#We retrospectively reviewed medical records for patients aged 4 to 18 years who were diagnosed with NAFLD and tested for thyroid function from January 2015 to December 2019 at 10 hospitals in Korea. @*Results@#The study included 428 patients with NAFLD. The prevalence of SH in pediatric NAFLD patients was 13.6%. In multivariate logistic regression, higher levels of steatosis on ultrasound and higher aspartate aminotransferase to platelet count ratio index (APRI) score were associated with increased risk of SH. Using receiver operating characteristic curves, the optimal cutoff value of the APRI score for predicting SH was 0.6012 (area under the curve, 0.67; P < 0.001; sensitivity 72.4%, specificity 61.9%, positive predictive value 23%, and negative predictive value 93.5%). @*Conclusion@#SH was often observed in patients with NAFLD, more frequently in patients with more severe liver damage. Thyroid function tests should be performed on pediatric NAFLD patients, especially those with higher grades of liver steatosis and fibrosis.

Anti-Saccharomyces cerevisiae Antibody in Pediatric Crohn’s Disease Patients without Mucosal Healing Is a Useful Marker of Mucosal Damage

Background/Aims@#We evaluated whether anti-Saccharomyces cerevisiae antibody (ASCA) titers are associated with diagnostic findings, disease activity, Paris classification phenotypes, and persistence after infliximab (IFX) treatment in children with Crohn’s disease (CD). We also investigated the role of ASCA as a predictor of mucosal healing (MH) and clinical remission (CR). @*Methods@#This study included 61 CD patients aged 19 years or younger who were diagnosed and treated between September 2010 and January 2019 and followed for at least 1 year. ASCA was regularly measured at the diagnosis of CD and at least 1 year after IFX therapy. @*Results@#The average follow-up period was 3.8±3.4 years (range, 1.0 to 7.2 years). Regression analysis showed that the ASCA titer was the only factor associated with Simple Endoscopic Score for Crohn's Disease (SES-CD) or CR among all the parameters. In patients who had achieved MH (SES-CD=0), ASCA immunoglobulin G (IgG) was not associated with MH, but in patients without MH, ASCA IgG was associated with SES-CD (p=0.005) and CR (p<0.001). The cutoff value of ASCA IgG in patients with CR was 21.8 units. However, there was no difference in the relapse rate between the ASCA IgG-positive and -negative groups during the follow-up period. @*Conclusions@#In patients who have not achieved MH, ASCA IgG is closely related to mucosal damage and CR. Unlike Western studies, ASCA IgG may be more helpful in predicting prognosis than immunoglobulin A in Korean patients, but it is not an appropriate indicator to predict the relapse of CD.

Factors Associated with the Immunogenicity of Anti-Tumor Necrosis Factor Agents in Pediatric Patients with Inflammatory Bowel Disease

Background/Aims@#Anti-drug antibodies (ADAs) can develop during treatment with anti-tumor necrosis factor (TNF) agents. We aimed to investigate the factors associated with immunogenicity of anti-TNF agents in pediatric patients with inflammatory bowel disease (IBD) and observe the clinical course of ADA-positive patients. @*Methods@#Pediatric IBD patients receiving maintenance treatment with anti-TNF agents who had been tested for ADAs against infliximab (IFX) or adalimumab (ADL) were included in this crosssectional study. Factors associated with ADA positivity were investigated by analyzing clinicodemographic, laboratory, and treatment-related factors. @*Results@#A total of 76 patients (Crohn’s disease, 65; ulcerative colitis, 11) were included. Among these, 59 and 17 patients were receiving IFX and ADL, respectively. ADAs were found in 10 patients (13.2%), all of whom were receiving IFX. According to multivariable logistic regression analysis, the IFX trough level (TL) was associated with ADA positivity (odds ratio, 0.25; 95% confidence interval [CI], 0.08 to 0.51; p=0.002). According to the receiver operating characteristic analysis, the optimal cutoff of the IFX TLs for stratifying patients based on the presence of ADAs against IFX was 1.88 μg/mL (area under curve, 0.941; 95% CI, 0.873 to 1.000; sensitivity, 80.0%; specificity, 95.9%; p<0.001). Among the 10 patients with ADAs against IFX, five patients (50%) switched to ADL within 1 year, while five patients (50%) kept receiving IFX. Transient ADAs were observed in three patients (30%). @*Conclusions@#IFX TL was the only factor associated with ADA formation in pediatric IBD patients receiving IFX. Future studies based on serial and proactive therapeutic drug monitoring are required in the future.

Infliximab Therapy for Children with Moderate to Severe Ulcerative Colitis:A Step-Up versus a Top-Down Strategy

Purpose@#We aimed to investigate clinical outcomes between top-down (TD) and conventional step-up (SU) therapies in pediatric patients with moderate to severe ulcerative colitis (UC). @*Materials and Methods@#All patients underwent clinical and endoscopic evaluation at diagnosis and 4 months and 1 year after treatment. Patients who started treatment with corticosteroid were grouped in the SU group, while those that initiated early infliximab (IFX) were grouped in the TD group. Among the SU group, patients who eventually changed to IFX treatment due to steroid resistance or dependency were included in the SU(R) group. @*Results@#In total, 44 children with moderate to severe UC were included for analysis. Twenty-one patients were included in the SU group, 23 were included in the TD group, and 10 were enrolled in the SU(R) group. Relapse rates were 47.6% (10/21) in the SU group and 17.4% (4/23) in the TD group (p=0.033). Among relapsed patients, the durations from remission to relapse were 17.3 months (0.9–46.9) in the SU group and 24.3 months (1.8–44.9) in the TD group. There was no statistically significant difference in the sustained durations of remission after IFX administration between the SU(R) and TD groups [3.9 (1.4–6.3) and 2.3 (0.3–5.2) years, respectively (p>0.05)]. @*Conclusion@#According to our study, early use of IFX without corticosteroid treatment for children with moderate to severe UC helps to lower relapse rates. We also found that IFX was a very effective treatment for pediatric UC, with a sustained duration of remission similar between TD and SU(R) groups.

Nationwide “Pediatric Nutrition Day” survey on the nutritional status of hospitalized children in South Korea

BACKGROUND/OBJECTIVES@#To evaluate the nutritional status and prevalence of malnutrition in hospitalized children at admission and during hospitalization in South Korea. @*SUBJECTS/METHODS@#This first cross-sectional nationwide “Pediatric Nutrition Day (pNday)” survey was conducted among 872 hospitalized children (504 boys, 368 girls; 686 medical, 186 surgical) from 23 hospitals in South Korea. Malnutrition risk was screened using the Pediatric Yorkhill Malnutrition Score (PYMS) and the Screening Tool Risk on Nutritional status and Growth. Nutritional status was assessed by z-scores of weight-for-age for underweight, weight-for-height for wasting, and height-for-age for stunting as well as laboratory tests. @*RESULTS@#At admission, of the 872 hospitalized children, 17.2% were underweight, and the prevalence of wasting and stunting was 20.2% and 17.3%, respectively. During hospitalization till pNday, 10.8% and 19.6% experienced weight loss and decreased oral intake, respectively.During the aforementioned period, fasting was more prevalent in surgical patients (7.5%) than in medical patients (1.6%) (P < 0.001). According to the PYMS, 34.3% and 30% of the children at admission and on pNday, respectively, had a high-risk of malnutrition, requiring consultation with the nutritional support team (NST). However, only 4% were actually referred to the NST during hospitalization. @*CONCLUSIONS@#Malnutrition was prevalent at admission and during hospitalization in pediatric patients, with many children experiencing weight loss and poor oral intake. To improve the nutritional status of hospitalized children, it is important to screen and identify all children at risk of malnutrition and refer malnourished patients to the multidisciplinary NST for proper nutritional interventions.

Procedural Sedation for Pediatric Upper Gastrointestinal Endoscopy in Korea

Background@#Sedative upper endoscopy is similar in pediatrics and adults, but it is characteristically more likely to lead to respiratory failure. Although recommended guidelines for pediatric procedural sedation are available within South Korea and internationally, Korean pediatric endoscopists use different drugs, either alone or in combination, in practice. Efforts are being made to minimize the risk of sedation while avoiding procedural challenges. The purpose of this study was to collect and analyze data on the sedation methods used by Korean pediatric endoscopists to help physicians perform pediatric sedative upper endoscopy (PSUE). @*Methods@#The PSUE procedures performed in 15 Korean pediatric gastrointestinal endoscopic units within a year were analyzed. Drugs used for sedation were grouped according to the method of use, and the depth of sedation was evaluated based on the Ramsay scores. The procedures and their complications were also assessed. @*Results@#In total, 734 patients who underwent PSUE were included. Sedation and monitoring were performed by an anesthesiologist at one of the institutions. The sedative procedures were performed by a pediatric endoscopist at the other 14 institutions. Regarding the number of assistants present during the procedures, 36.6% of procedures had one assistant, 38.8%had 2 assistants, and 24.5% had 3 assistants. The average age of the patients was 11.6 years old. Of the patients, 19.8% had underlying diseases, 10.0% were taking medications such as epilepsy drugs, and 1.0% had snoring or sleep apnea history. The average duration of the procedures was 5.2 minutes. The subjects were divided into 5 groups as follows: 1) midazolam + propofol + ketamine (M + P + K): n = 18, average dose of 0.03 + 2.4 + 0.5 mg/kg;2) M + P: n = 206, average dose of 0.06 + 2.1 mg/kg; 3) M + K: n = 267, average dose of 0.09 + 0.69 mg/kg; 4) continuous P infusion for 20 minutes: n = 15, average dose of 6.6 mg/kg; 5) M: n = 228, average dose of 0.11 mg/kg. The average Ramsay score for the five groups was 3.7, with significant differences between the groups (P < 0.001). Regarding the adverse effects, desaturation and increased oxygen supply were most prevalent in the M + K group. Decreases and increases in blood pressure were most prevalent in the M + P + K group, and bag-mask ventilation was most used in the M + K group. There were no reported incidents of intubation or cardiopulmonary resuscitation. A decrease in oxygen saturation was observed in 37 of 734 patients, and it significantly increased in young patients (P = 0.001) and when ketamine was used (P = 0.014). Oxygen saturation was also correlated with dosage (P = 0.037). The use of ketamine (P < 0.001) and propofol (P < 0.001) were identified as factors affecting the Ramsay score in the logistic regression analysis. @*Conclusion@#Although the drug use by Korean pediatric endoscopists followed the recommended guidelines to an extent, it was apparent that they combined the drugs or reduced the doses depending on the patient characteristics to reduce the likelihood of respiratory failure. Inducing deep sedation facilitates comfort during the procedure, but it also leads to a higher risk of complications.

Severe Phenotype of Non-alcoholic Fatty Liver Disease in Pediatric Patients with Subclinical Hypothyroidism: a Retrospective Multicenter Study from Korea

Background@#It is uncertain whether non-alcoholic fatty liver disease (NAFLD) is associated with subclinical hypothyroidism (SH) in pediatric patients. The purpose of this study was to investigated the prevalence and related factors of SH in pediatric patients with NAFLD. We also evaluate the association between liver fibrosis and SH. @*Methods@#We retrospectively reviewed medical records for patients aged 4 to 18 years who were diagnosed with NAFLD and tested for thyroid function from January 2015 to December 2019 at 10 hospitals in Korea. @*Results@#The study included 428 patients with NAFLD. The prevalence of SH in pediatric NAFLD patients was 13.6%. In multivariate logistic regression, higher levels of steatosis on ultrasound and higher aspartate aminotransferase to platelet count ratio index (APRI) score were associated with increased risk of SH. Using receiver operating characteristic curves, the optimal cutoff value of the APRI score for predicting SH was 0.6012 (area under the curve, 0.67; P < 0.001; sensitivity 72.4%, specificity 61.9%, positive predictive value 23%, and negative predictive value 93.5%). @*Conclusion@#SH was often observed in patients with NAFLD, more frequently in patients with more severe liver damage. Thyroid function tests should be performed on pediatric NAFLD patients, especially those with higher grades of liver steatosis and fibrosis.

Anti-Saccharomyces cerevisiae Antibody in Pediatric Crohn’s Disease Patients without Mucosal Healing Is a Useful Marker of Mucosal Damage

Background/Aims@#We evaluated whether anti-Saccharomyces cerevisiae antibody (ASCA) titers are associated with diagnostic findings, disease activity, Paris classification phenotypes, and persistence after infliximab (IFX) treatment in children with Crohn’s disease (CD). We also investigated the role of ASCA as a predictor of mucosal healing (MH) and clinical remission (CR). @*Methods@#This study included 61 CD patients aged 19 years or younger who were diagnosed and treated between September 2010 and January 2019 and followed for at least 1 year. ASCA was regularly measured at the diagnosis of CD and at least 1 year after IFX therapy. @*Results@#The average follow-up period was 3.8±3.4 years (range, 1.0 to 7.2 years). Regression analysis showed that the ASCA titer was the only factor associated with Simple Endoscopic Score for Crohn's Disease (SES-CD) or CR among all the parameters. In patients who had achieved MH (SES-CD=0), ASCA immunoglobulin G (IgG) was not associated with MH, but in patients without MH, ASCA IgG was associated with SES-CD (p=0.005) and CR (p<0.001). The cutoff value of ASCA IgG in patients with CR was 21.8 units. However, there was no difference in the relapse rate between the ASCA IgG-positive and -negative groups during the follow-up period. @*Conclusions@#In patients who have not achieved MH, ASCA IgG is closely related to mucosal damage and CR. Unlike Western studies, ASCA IgG may be more helpful in predicting prognosis than immunoglobulin A in Korean patients, but it is not an appropriate indicator to predict the relapse of CD.