Comparison of endoscopic healing and durability between infliximab originator and CT-P13 in pediatric patients with inflammatory bowel disease.

Background and aims: Favourable clinical data were published on the efficacy of CT-P13, the first biosimilar of infliximab (IFX), in pediatric inflammatory bowel disease (IBD); however, few studies have compared the effect on endoscopic healing (EH) and drug retention rate between the IFX originator and CT-P13. Therefore, we aimed to compare EH and the drug retention rate between the IFX originator and CT-P13. Methods: Children with Crohn's disease (CD) and ulcerative colitis (UC)/IBD-unclassified (IBD-U) at 22 medical centers were enrolled, with a retrospective review conducted at 1-year and last follow-up. Clinical remission, EH and drug retention rate were evaluated. Results: We studied 416 pediatric patients with IBD: 77.4% had CD and 22.6% had UC/IBD-U. Among them, 255 (61.3%) received the IFX originator and 161 (38.7%) received CT-P13. No statistically significant differences were found between the IFX originator and CT-P13 in terms of corticosteroid-free remission and adverse events. At 1-year follow-up, EH rates were comparable between them (CD: P=0.902, UC: P=0.860). The estimated cumulative cessation rates were not significantly different between the two groups. In patients with CD, the drug retention rates were 66.1% in the IFX originator and 71.6% in the CT-P13 group at the maximum follow-up period (P >0.05). In patients with UC, the drug retention rates were 49.8% in the IFX originator and 56.3% in the CT-P13 group at the maximum follow-up period (P >0.05). Conclusions: The IFX originator and CT-P13 demonstrated comparable therapeutic response including EH, clinical remission, drug retention rate and safety in pediatric IBD.

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

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.

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

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, ß=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.

The Changes in Trends of Lower Gastrointestinal Endoscopy Conducted in Children and Adolescents after the COVID-19 Outbreak in Korea.

Background and Objectives: The coronavirus disease 2019 (COVID-19) pandemic has affected medical practice in diverse ways. We aimed to investigate the change in trends of lower gastrointestinal (LGI) endoscopy conducted in children and adolescents after the COVID-19 outbreak in Korea. Material and Methods: This was a multicenter, retrospective study conducted in Korea. We included children and adolescents aged <19 years who had undergone their first LGI endoscopy between 2016 and 2020. We compared clinicodemographic and endoscopic factors between groups divided according to the pre- and postCOVID-19 era in Korea. Results: We included 1307 patients in this study. Colonoscopies, instead of sigmoidoscopies, were conducted in most patients in the postCOVID-19 era compared to those in the preCOVID-19 era (86.9% vs. 78.5%, p = 0.007). The diagnosis of inflammatory bowel disease (IBD) was also significantly higher in the postCOVID-19 era compared to the preCOVID-19 era (47.2% vs. 28.5%, p < 0.001). According to multivariate logistic regression analysis, age at LGI endoscopy, LGI bleeding indication, and IBD diagnosis were independently associated with the use of a colonoscopy over a sigmoidoscopy (odds ratio (OR) 1.19, 95% confidence interval (CI) 1.12−1.27, p < 0.001; OR 0.56, 95% CI 0.37−0.83, p = 0.005; OR 1.80, 95% CI 1.20−2.77, p = 0.006, respectively). Conclusions: The COVID-19 pandemic has changed LGI endoscopy practice trends of pediatric gastroenterologists in Korea, who tended to perform lesser LGI endoscopies compared to previous years while conducting significantly more colonoscopies than sigmoidoscopies in the postCOVID-19 era. Furthermore, these colonoscopies were significantly associated with the diagnosis of IBD, as well as a significant increase in IBD diagnosis in the postCOVID-19 era.

Epidemiological Trends of Pediatric Inflammatory Bowel Disease in Korea: A Multicenter Study of the Last 3 Years Including the COVID-19 Era.

BACKGROUND: Studies on how the coronavirus pandemic has affected pediatric inflammatory bowel disease (PIBD) are lacking. We aimed to investigate the trends in epidemiology, characteristics, initial management, and short-term outcomes of PIBD in South Korea over the recent three years including the era of coronavirus disease 2019 (COVID-19). METHODS: This multicenter study retrospectively investigated temporal trends in the epidemiology of PIBD in Korea. Annual occurrences, disease phenotypes, and initial management at diagnosis were analyzed from January 2018 to June 2021. RESULTS: A total of 486 patients from 17 institutions were included in this epidemiological evaluation. Analysis of the occurrence trend confirmed a significant increase in PIBD, regardless of the COVID-19 pandemic. In Crohn's disease, patients with post-coronavirus outbreaks had significantly higher fecal calprotectin levels than those with previous onset (1,339.4 ± 717.04 vs. 1,595.5 ± 703.94, P = 0.001). Patients with post-coronavirus-onset ulcerative colitis had significantly higher Pediatric Ulcerative Colitis Activity Index scores than those with previous outbreaks (48 ± 17 vs. 36 ± 15, P = 0.004). In the initial treatment of Crohn's disease, the use of 5-aminosalicylic acid (5-ASA) and steroids significantly decreased (P = 0.006 and 0.001, respectively), and enteral nutrition and the use of infliximab increased significantly (P = 0.045 and 0.009, respectively). There was a significant increase in azathioprine use during the initial treatment of ulcerative colitis (P = 0.020). CONCLUSION: Regardless of the COVID-19 pandemic, the number of patients with PIBD is increasing significantly annually in Korea. The initial management trends for PIBD have also changed. More research is needed to establish appropriate treatment guidelines considering the epidemiological and clinical characteristics of Korean PIBD.

Neutralizing Antibody Response, Safety, and Efficacy of mRNA COVID-19 Vaccines in Pediatric Patients with Inflammatory Bowel Disease: A Prospective Multicenter Case-Control Study.

The vaccination of immunocompromised children against coronavirus disease 2019 is an important public health issue. We evaluated the serological response, safety, and efficacy of the BNT162b2 vaccine in children with and without inflammatory bowel disease (IBD). A prospective, multicenter, case-control study was conducted in a pediatric population, including patients with IBD, aged 12-18 years. Clinical characteristics, safety profile, and serum samples for surrogate virus-neutralizing antibody testing pre- and post-BNT162b2 vaccination were assessed. The breakthrough infection rate during the Omicron outbreak was calculated to evaluate efficacy. Fifteen controls and twenty-three patients with IBD were enrolled. After two vaccine doses, the median level of percentage inhibition was highly increased, without significant differences between the groups (control 96.9 and IBD 96.3). However, it was significantly reduced in IBD patients receiving combination therapy (anti-tumor necrosis factor-α + immunomodulators) relative to those in other therapies and controls. Serious adverse events were not observed. The breakthrough infection rate was 42.1%, without statistical differences between the groups. Immunization with BNT162b2 in patients with IBD was comparable with that in healthy adolescents in terms of immunogenicity and safety. Nevertheless, the efficacy of BNT162b2 in preventing infection caused by the Omicron variant in the pediatric population was insufficient.

Transmural healing evaluated by magnetic resonance enterography in paediatric patients with Crohn's disease receiving maintenance treatment with biologics.

BACKGROUND: The optimal treatment goal in Crohn's disease (CD) is endoscopic healing (EH). However, transmural healing (TH) facilitated by the development and increasing performance of magnetic resonance enterography (MRE) is emerging as a potential treatment goal. AIMS: To assess TH rates after 1 year of treatment by MRE and its relationship with EH in paediatric patients with CD receiving anti-tumour necrosis factor (TNF) agents, and to investigate factors associated with TH after 1 year of treatment. METHODS: This multi-centre, prospective, observational study included Korean paediatric patients with luminal CD diagnosed at age < 19 years who were naïve to anti-TNF treatment. They simultaneously underwent ileocolonoscopy and MRE at baseline and after 1 year of treatment with biologics. RESULTS: We included 116 patients. At 1 year, EH and TH were achieved in 59.5% (69/116) and 38.8% (45/116) of the patients, respectively. Both EH and TH was observed in 35.3% (41/116), EH without TH in 24.1% (28/116), TH without EH in 3.4% (4/116), and neither EH nor TH in 37.1% (43/116). Moreover, 59.4% (41/69) of patients who achieved EH at 1 year exhibited TH, and 91.1% (41/45) of patients who achieved TH exhibited EH. Baseline MaRIA score was associated with TH according to a multivariate analysis (OR 0.97, 95% CI 0.95-0.99, p = 0.023). CONCLUSION: TH is a more stringent goal than EH. Regular follow-up evaluation of transmural status, and efforts to achieve TH, may alter the natural course of CD in the era of treat-to-target.

Effects of anxiety on sedation among pediatric patients undergoing esophagogastroduodenoscopy.

We investigated whether the severity of anxiety among children undergoing endoscopy could affect sedation. We prospectively recruited patients under 18 years of age who were scheduled to undergo esophagogastroduodenoscopy (EGD). Baseline anxiety was evaluated using the Spence Children's Anxiety Scale (SCAS). Our analysis considered the type and dose of sedative drugs, degree of sedation, and complications associated with sedation according to the scale score. The mean total SCAS T-scores and each subscale score were significantly higher in the 6-12-year age group. The mean T-score among patients who exhibited irritability during EGD was higher than that among other patients, with significant differences in the Total, Obsessive Disorder, Panic Agoraphobia and General Anxiety subscales. The midazolam doses of children exhibiting irritability were more likely to need higher (p = 0.006). Other sedation-related complications were not associated with the T-scores in each subscale. Total sleep time was not associated with any T-score subscales. Anxiety levels were significantly higher among 6-12-year-olds and children exhibiting irritability. Anxiety was often associated with irritability, difficulties achieving adequate sedation during EGD, and additional sedative drug administration. We recommend higher doses or more potent drugs to facilitate endoscopy for children with high anxiety levels.

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%; negative predictive 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.

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.

A Multicenter Study of Real-world Practice for Management of Abnormal Liver Function Tests in Children with Acute Infectious Diseases.

BACKGROUND: Abnormal liver function tests (LFTs) are commonly seen in pediatric patients with acute infectious diseases. Few studies and no definite clinical guidelines for these conditions are available. The present study aimed to elucidate the causes and factors associated with prolongation of liver enzyme elevation. We also investigated actual real-world practices in Korea. METHODS: A retrospective study was performed on all patients younger than 18 years, who visited six tertiary teaching hospitals around Korea in 2018 for acute infectious diseases and showed alanine aminotransferase (ALT) levels above 60 IU/L without other specific conditions that could cause ALT elevation. We categorized the infections that cause LFT elevation into six groups: respiratory infection, gastrointestinal infection, urinary tract infection, other febrile disease, Epstein-Barr virus infection, and cytomegalovirus infection. We collected data on the medical specialty of the attending physician who followed up the subject, follow-up duration, percentage of follow-up loss, and their investigation. RESULTS: A total of 613 patients were enrolled in this study, half of whom (50.7%) were younger than 12 months. The mean initial aspartate aminotransferase and ALT values were 171.2 ± 274.1 and 194.9 ± 316.1 IU/L (range 23-2,881, 60-2,949 IU/L), respectively; however, other LFTs were within the normal range. Respiratory infection was the most common diagnosis (45.0%), and rhinovirus was the most commonly identified pathogen (9.8%). The follow-up rate was higher with pediatric gastroenterologists (90.5%) and non-gastroenterology pediatricians (76.4%) than with pediatric residents and emergency doctors. Older age was related to better ALT recovery (odds ratio [OR] of age for month = 1.003; 95% confidence interval [CI], 1.001-1.004; P = 0.004), while the number of infection episodes (OR = 0.626; 95% CI, 0.505-0.777; P < 0.001) was associated with poor ALT recovery. Abdominal sonography was the most commonly used diagnostic tool (36.9%), followed by the hepatotropic virus workup. The modalities of hepatitis workup were significantly differently applied by physicians based on their specialties and institutions. CONCLUSION: Abnormal liver function test after a systemic infection was common in respiratory infection and under the age of 1 year. Age, number of infections, and initial results of LFTs were related to ALT recovery time. Inter-physician, inter-institution, and inter-specialty variances were observed in real-world practice.

Successful removal of two magnets in the small intestine by laparoscopy and colonoscopy: A case report.

BACKGROUND: Ingestion of multiple magnets can cause serious gastrointestinal complications, such as obstruction, fistulae, and perforation. When multiple magnets traverse the stomach, coordination between pediatric gastroenterologists and pediatric surgeons is recommended, and ultimate management is required dependent on clinical concerns. CASE SUMMARY: A 5-year-old girl swallowed 2 small magnets that then remained in the right lower quadrant (RLQ) of the abdomen for 3 d; this required endoscopic and laparoscopic intervention. Abdominal X-ray and computed tomography revealed high-density objects in the RLQ area. Colonoscopy after proper bowel preparations on the third day of ingestion revealed no foreign body in the colonic area or the end of the ileum. The two magnets were removed via colonoscopy with laparoscopic intervention. CONCLUSION: It is important to establish effective coordination between pediatric gastroenterologists and pediatric surgeons when using a non-invasive procedure to remove magnets.

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.

Urinary Microbiome Characteristics in Female Patients with Acute Uncomplicated Cystitis and Recurrent Cystitis.

Traditionally, the diagnostic mainstay of recurrent urinary tract infection has been urinary culture. However, the causative uropathogen of recurrent cystitis has not been well established. Urine DNA next-generation sequencing (NGS) can provide additional information on these infections. Herein, we compared urine NGS results and urine cultures in patients with acute uncomplicated cystitis (AUC) and recurrent cystitis (RC), and evaluated the difference in microbiome patterns in the NGS results. Patients who underwent urine culture and NGS due to AUC or RC were retrospectively reviewed. All urine samples were collected via a transurethral catheter and studied utilizing a type of NGS called 16S ribosomal RNA gene amplification and sequencing. The sensitivity of urine NGS was significantly higher than that of conventional urine culture (69.0% vs. 16.7%, p < 0.05). The detection rate of urine NGS was slightly lower in the RC group than in the AUC group (67.7% vs. 72.7%). Microbiome diversity was significantly higher in the RC group compared to the AUC group (p = 0.007), and the microbiome composition was significantly different between the AUC and RC groups. In the urine NGS results, Pseudomonas, Acinetobacter, and Enterobacteriaceae were found in the AUC group, and Sphingomonas, Staphylococcus, Streptococcus, and Rothia spp. were detected in the RC group. Urine NGS can significantly increase the diagnostic sensitivity compared to traditional urine culture methods, especially in RC patients. AUC and RC patients had significant differences in bacterial diversity and patterns. Therefore, recurrent cystitis might be approached from a different perspective.

Collagenous gastroduodenocolitis in a Korean adolescent: first pediatric case report in Asia.

Collagenous gastritis (CG) is a rare disease diagnosed histologically by the subepithelial deposition of collagen bands thicker than 10 µm and the infiltration of inflammatory mononuclear cells in the lamina propria. The definite pathophysiology is yet to be elucidated. However, recent studies have suggested that the collagen deposition may be the result of a reparative process in response to an earlier inflammatory, autoimmune, infectious, or toxic insult. CG is divided into the pediatric- and adult-type. While the pediatric-type is limited to the stomach, the adult-type involves not only the stomach but also the intestine and/or colon. We report a rare case of adult-type CG in a 15-year-old boy who initially presented with abdominal pain and iron-deficiency anemia. Esophagogastroduodenoscopy (EGD) revealed findings suspicious for Helicobacter pylori (H. pylori) gastritis. Although histology did not reveal the organism, campylobacter-like organism (CLO) test was positive. Based on the diagnosis of suspicious H. pylori gastritis, eradication was conducted using the triple drug regimen. However, symptoms of intermittent abdominal pain persisted and diarrhea newly developed one year later. Histologic results from biopsies from the stomach, duodenum, and colon revealed findings compatible with CG, collagenous duodenitis (CD), and collagenous colitis (CC). This is the first pediatric case of collagenous gastroduodenocolitis (CGDC) reported in Asia. It is no longer assumed that adult-type and pediatric-type CG should be classified as an independent disease, but should be considered as similar diseases on a continuous spectrum. Therefore, children and adolescents diagnosed with CG should also consider undergoing a colonoscopy for the evaluation of possible coexisting CC when concurrent lower gastrointestinal symptoms are present. Moreover, considering the possibility of negative findings on the first endoscopy, repeat endoscopy should be considered when symptoms persist.

Mucosal Healing in Paediatric Patients with Moderate-to-Severe Luminal Crohn's Disease Under Combined Immunosuppression: Escalation versus Early Treatment.

BACKGROUND AND AIMS: We aimed to compare the efficacy of combined immunosuppression in terms of mucosal healing in paediatric patients with moderate-to-severe luminal Crohn's disease receiving infliximab according to either an 'escalated combined immunosuppression' or an 'early combined immunosuppression' strategy. METHODS: In this prospective observational study, the efficacy of combined immunosuppression was evaluated in terms of mucosal healing at weeks 14 and 54 from baseline infliximab infusion. Comparison was performed between the escalated combined immunosuppression group [group A] and the early combined immunosuppression group [group B]. Factors associated with mucosal healing at weeks 14 and 54 from baseline infliximab infusion were also investigated. RESULTS: Seventy-six patients initiated infliximab with concomitant azathioprine [group A = 28; group B = 48]. Comparison of baseline characteristics revealed a significantly longer duration from initial diagnosis to infliximab infusion in group A [median 8.1 vs. 0.7 months; p < 0.001]. Mucosal healing was achieved in 32% of patients in group A and 51% in group B at week 14 [p = 0.121], and in 42% in group A and 74% in group B at week 54 [p = 0.007]. Group B was also positively associated with mucosal healing at week 54 on multivariate logistic regression [odds ratio = 6.216, 95% confidence interval = 1.782-21.686, p = 0.004]. CONCLUSIONS: Mucosal healing during combined immunosuppression is more effectively achieved by treatment with an early combined immunosuppression strategy without corticosteroid induction administered within 1 month rather than escalating to receive combination therapy later during the course. The therapeutic window of opportunity in early Crohn's disease may be shorter than generally thought, especially in children.

Enhancement of cysteine catabolism into taurine impacts glutathione homeostasis in rats challenged with ethanol.

We determined the alterations in metabolic conversion of cysteine into glutathione and taurine in liver of rats treated with ethanol acutely. Ethanol treatment reduced cysteine as well as glutathione levels in liver for 24 h. However, cysteine dioxygenase was up-regulated rapidly, and hypotaurine/taurine levels were significantly higher than those found in the saline-treated rats. It is therefore suggested that enhancement of cysteine catabolism into taurine contributes to the depletion of hepatic glutathione, which could exacerbate the ethanol-induced oxidative liver injury.

Infliximab "Top-Down" Strategy is Superior to "Step-Up" in Maintaining Long-Term Remission in the Treatment of Pediatric Crohn Disease.

OBJECTIVES: We aimed to compare the efficacy of remission maintenance between infliximab "top-down" and "step-up" strategies in moderate to severe pediatric Crohn disease during 3 years. We also aimed to determine prognostic factors that may influence the relapse-free rate in these patients. METHODS: The present study was a retrospective review of a prospective cohort, based on an infliximab treatment protocol for pediatric Crohn disease used at Samsung Medical Center. A total of 31 patients (group A) were treated with early infliximab induction ("top-down" strategy) and 20 patients (group B) refractory to conventional therapy underwent infliximab treatment ("step-up" strategy). The efficacy of infliximab treatment was assessed by relapse-free rate and remission period rate for 3 years. A total of 11 prognostic factors that may influence the relapse-free rate were further analyzed. RESULTS: The relapse-free rates at 3 years were 35.5% (95% confidence interval [CI] 0.194-0.519) in group A and 15.0% (95% CI 0.037-0.335) in group B (P = 0.0094). Overall remission period rate for 3 years also showed a significant difference between the 2 groups (92.1%  ± 7.2% vs 78.3%  ± 16.6%; P = 0.005). Multivariable analysis revealed that the duration from the initial diagnosis to infliximab infusion was the only factor associated with relapse-free remission for 3 years (hazard ratio = 1.077; 95% CI 1.025-1.131). CONCLUSIONS: "Top-down" strategy had a longer remission period compared with the "step-up" strategy in pediatric Crohn disease during a study period of 3 years, based on relapse-free rate and remission period rate. Earlier introduction of infliximab is recommended in pediatric patients with moderate to severe Crohn disease.