Background/Aims: The prospective Crohn’s Disease Clinical Network and Cohort Study is a nationwide multicenter cohort study of patients with Crohn’s disease (CD) in Korea, aiming to prospectively investigate the clinical features and long-term prognosis associated with CD. Methods: Patients diagnosed with CD between January 2009 and September 2019 were prospectively enrolled. They were divided into two cohorts according to the year of diagnosis: cohort 1 (diagnosed between 2009 and 2011) versus cohort 2 (between 2012 and 2019). Results: A total of 1,175 patients were included, and the median follow-up duration was 68 months (interquartile range, 39.0 to 91.0 months). The treatment-free durations for thiopurines (p<0.001) and anti-tumor necrosis factor agents (p=0.018) of cohort 2 were shorter than those of cohort 1. Among 887 patients with B1 behavior at diagnosis, 149 patients (16.8%) progressed to either B2 or B3 behavior during follow-up. Early use of thiopurine was associated with a reduced risk of behavioral progression (adjusted hazard ratio [aHR], 0.69; 95% confidence interval [CI], 0.50 to 0.90), and family history of inflammatory bowel disease was associated with an increased risk of behavioral progression (aHR, 2.29; 95% CI, 1.16 to 4.50). One hundred forty-one patients (12.0%) underwent intestinal resection, and the intestinal resection-free survival time was significantly longer in cohort 2 than in cohort 1 (p=0.003). The early use of thiopurines (aHR, 0.35;95% CI, 0.23 to 0.51) was independently associated with a reduced risk of intestinal resection. Conclusions The prognosis of CD in Korea appears to have improved over time, as evidenced by the decreasing intestinal resection rate. Early use of thiopurines was associated with an improved prognosis represented by a reduced risk of intestinal resection.

Background and Objectives: The relationship between the hospital percutaneous coronary intervention (PCI) volumes and the in-hospital clinical outcomes of patients with acute myocardial infarction (AMI) remains the subject of debate. This study aimed to determine whether the in-hospital clinical outcomes of patients with AMI in Korea are significantly associated with hospital PCI volumes. Methods: We selected and analyzed 17,121 cases of AMI, that is, 8,839 cases of non-ST-segment elevation myocardial infarction and 8,282 cases of ST-segment elevation myocardial infarction, enrolled in the 2014 Korean percutaneous coronary intervention (K-PCI) registry. Patients were divided into 2 groups according to hospital annual PCI volume, that is, to a high-volume group (≥400/year) or a low-volume group (<400/year). Major adverse cardiovascular and cerebrovascular events (MACCEs) were defined as composites of death, cardiac death, non-fatal myocardial infarction (MI), stent thrombosis, stroke, and need for urgent PCI during index admission after PCI. Results: Rates of MACCE and non-fatal MI were higher in the low-volume group than in the high-volume group (MACCE: 10.9% vs. 8.6%, p=0.001; non-fatal MI: 4.8% vs. 2.6%, p=0.001, respectively). Multivariate regression analysis showed PCI volume did not independently predict MACCE. Conclusions Hospital PCI volume was not found to be an independent predictor of in-hospital clinical outcomes in patients with AMI included in the 2014 K-PCI registry.

PURPOSE: In this study, we investigated the role of neutrophil to lymphocyte ratio (NLR) as a predictor of tumor response and as a prognostic factor in patients with rectal cancer who had undergone curative surgery after neoadjuvant chemoradiation therapy (nCRT). METHODS: Between January 2009 and July 2016, we collected 140 consecutive patients who had undergone curative intent surgery after nCRT due to rectal adenocarcinoma. We obtained the pre- and post-nCRT NLR by dividing the neutrophil count by the lymphocyte count. The cutoff value was obtained using receiver operating characteristic analysis for tumor response and using maximally selected rank analysis for recurrence-free survival (RFS). The relationship among NLR, tumor response, and RFS was assessed by adjusting the possible clinico-pathological confounding factors. RESULTS: The possibility of pathologic complete response (pCR) was significantly decreased in high pre- (>2.77) and postnCRT NLR (>3.23) in univariate regression analysis. In multivariate analysis, high post-nCRT NLR was an independent negative predictive factor for pCR (adjusted odds ratio, 0.365; 95% confidence interval [CI], 0.145–0.918). The 5-year RFS of all patients was 74.6% during the median 37 months of follow-up. Patients with higher pre- (>2.66) and post-nCRT NLR (>5.21) showed lower 5-year RFS rates (53.1 vs. 83.3%, P = 0.006) (69.2 vs. 75.7%, P = 0.054). In multivariate Cox analysis, high pre-nCRT NLR was an independent poor prognostic factor for RFS (adjusted hazard ratio, 2.300; 95% CI, 1.061–4.985). CONCLUSION: Elevated NLR was a negative predictive marker for pCR and was independently associated with decreased RFS. For confirmation, a large-scale study with appropriate controls is needed.
Adenocarcinoma ; Biomarkers ; Chemoradiotherapy ; Follow-Up Studies ; Humans ; Lymphocyte Count ; Lymphocytes ; Multivariate Analysis ; Neutrophils ; Odds Ratio ; Polymerase Chain Reaction ; Prognosis ; Rectal Neoplasms ; ROC Curve

BACKGROUND/AIMS: In some cases, chronic diarrhea is unexplained, and small bowel disorders may be one of the causes. The aim of this study was to assess the diagnostic yield and clinical impact of video capsule endoscopy (VCE) in patients with chronic diarrhea. METHODS: We retrospectively analyzed records from October 2002 to August 2013 in the VCE nationwide database registry (n=2,964). Ninety-one patients from 15 medical centers (60 males and 31 females; mean age, 47±19 years) were evaluated for VCE as a result of chronic diarrhea. RESULTS: The duration of chronic diarrhea was 8.3±14.7 months. The positive diagnostic yield of VCE was 42.9% (39/91). However, 15.4% (14/91) exhibited an inconsistent result, and 41.8% (38/91) were negative. Abnormal findings consistent with chronic diarrhea included erosions/aphthous ulcers (19.8%), ulcers (17.6%), mucosal erythema (3.3%), edema (1.1%), and luminal narrowing (1.1%). The most common diagnoses were functional diarrhea associated with irritable bowel syndrome in 37 patients (40.7%) and Crohn’s disease in 18 patients (19.8%). After VCE examination, the diagnosis was changed in 34.1% of the patients (31/91). Hematochezia (odds ratio [OR], 8.802; 95% confidence interval [CI], 2.126 to 36.441) and hypoalbuminemia (OR, 4.811; 95% CI, 1.241 to 18.655) are predictive factors of a positive diagnostic yield. CONCLUSIONS: VCE had a favorable diagnostic yield and clinical impact on the management of patients with chronic diarrhea.
Capsule Endoscopy* ; Diagnosis ; Diarrhea* ; Edema ; Erythema ; Female ; Gastrointestinal Hemorrhage ; Humans ; Hypoalbuminemia ; Irritable Bowel Syndrome ; Male ; Phenobarbital ; Retrospective Studies ; Ulcer

BACKGROUND/AIMS: Gastric pathology and Helicobacter pylori (H. pylori) infection among Asian patients with Crohn's disease (CD) are still unclear. We evaluated gastric histologic features and frequency of H. pylori infection in Korean patients with CD. METHODS: Among 492 patients with CD receiving upper gastrointestinal (GI) endoscopic evaluation in 19 Korean hospitals, we evaluated the endoscopic findings and gastric histopathologic features of 47 patients for our study. Histopathologic classification was performed using gastric biopsy tissues, and H. pylori infection was determined using the rapid urease test and histology. RESULTS: There were 36 men (76.6%), and the median age of patients at the time of upper GI endoscopy was 23.8 years (range, 14.2-60.5). For CD phenotype, ileocolonic disease was observed in 38 patients (80.9%), and non-stricturing, non-penetrating disease in 31 patients (66.0%). Twenty-eight patients (59.6%) complained of upper GI symptoms. Erosive gastritis was the most common gross gastric feature (66.0%). Histopathologically, H. pylori-negative chronic active gastritis (38.3%) was the most frequent finding. H. pylori testing was positive in 11 patients (23.4%), and gastric noncaseating granulomata were detected in 4 patients (8.5%). Gastric noncaseating granuloma showed a statistically significant association with perianal abscess/fistula (P=0.0496). CONCLUSIONS: H. pylori-negative chronic active gastritis appears to be frequent among Korean patients with CD. The frequency of H. pylori infection was comparable with previous studies. An association with perianal complications suggests a prognostic value for gastric noncaseating granuloma in patients with CD.
Asian Continental Ancestry Group ; Biopsy ; Classification ; Crohn Disease* ; Endoscopy ; Gastritis ; Granuloma ; Helicobacter pylori ; Humans ; Korea* ; Male ; Pathology ; Phenotype ; Stomach ; Urease

PURPOSE: Infliximab is currently used for the treatment of active Crohn's disease (CD). We aimed to assess the efficacy and safety of infliximab therapy and to determine the predictors of response in Korean patients with CD. MATERIALS AND METHODS: A total of 317 patients who received at least one infliximab infusion for active luminal CD (n=198) and fistulizing CD (n=86) or both (n=33) were reviewed retrospectively in 29 Korean referral centers. Clinical outcomes of induction and maintenance therapy with infliximab, predictors of response, and adverse events were evaluated. RESULTS: In patients with luminal CD, the rates of clinical response and remission at week 14 were 89.2% and 60.0%, respectively. Male gender and isolated colonic disease were associated with higher remission rates at week 14. In week-14 responders, the probabilities of sustained response and remission were 96.2% and 93.3% at week 30 and 88.0% and 77.0% at week 54, respectively. In patients with fistulizing CD, clinical response and remission were observed in 85.0% and 56.2% of patients, respectively, at week 14. In week-14 responders, the probabilities of sustained response and remission were 94.0% and 97.1%, respectively, at both week 30 and week 54. Thirty-nine patients (12.3%) experienced adverse events related to infliximab. Serious adverse events developed in 19 (6.0%) patients including seven cases of active pulmonary tuberculosis. CONCLUSION: Infliximab induction and maintenance therapy are effective and well tolerable in Korean patients with luminal and fistulizing CD. However, clinicians must be aware of the risk of rare yet critical adverse events.
Colonic Diseases ; Crohn Disease* ; Humans ; Infliximab* ; Male ; Phenobarbital ; Referral and Consultation ; Retrospective Studies ; Tuberculosis ; Tuberculosis, Pulmonary

BACKGROUND/AIMS: We evaluated the long-term outcome and clinical course of patients of nonsteroidal anti-inflammatory drug (NSAID)-induced small intestinal injury by performing capsule endoscopy (CE). METHODS: A multicenter retrospective study was conducted using data collected from the CE nationwide database registry, which has been established since 2002. RESULTS: A total of 140 patients (87 males; mean age, 60.6+/-14.8 years) from the CE nationwide database registry (n=2,885) were diagnosed with NSAID-induced small intestinal injury and enrolled in our study. Forty-nine patients (35.0%) presented with a history of aspirin use and an additional 49 (35.0%) were taking NSAIDs without aspirin. The most prominent findings after performing CE were multiple ulcerations (n=82, 58.6%) and erosions or aphthae (n=32, 22.9%). During the follow-up period (mean, 15.9+/-19.0 months; range, 0 to 106 months), NSAID-induced small intestinal injury only recurred in six patients (4.3%). Older age and hypertension were positive predictive factors for recurrence. CONCLUSIONS: These results suggest that the recurrence of NSAID-induced small bowel injury was not frequent in the presence of conservative treatment. Therefore, the initial diagnosis using CE and the medication history are important.
Age Factors ; Aged ; Anti-Inflammatory Agents, Non-Steroidal/*adverse effects ; Aspirin/adverse effects ; *Capsule Endoscopy ; Female ; Humans ; Intestinal Diseases/chemically induced/*pathology ; Intestine, Small/*drug effects/injuries/*pathology ; Male ; Middle Aged ; Recurrence ; Republic of Korea ; Retrospective Studies ; Time Factors ; Ulcer/chemically induced/*pathology

BACKGROUND/AIMS: Capsule endoscopy (CE) is widely used. However, CE has limitations including incomplete examination, inadequate bowel preparation, and retention. The aim of this study was to estimate the indications for and detection, completion, and retention rates of small intestine CE based on the 10-year data from the Korean Capsule Endoscopy Registry. METHODS: Twenty-four hospitals participated in this study. Clinical information, such as reasons for CE, method and quality of bowel preparation, and incomplete examination and capsule retention rates, was collected and analyzed. RESULTS: A total of 2,914 CEs were registered. The most common reason for CE was obscure gastrointestinal bleeding (59%). Significant lesions were detected in 66% of cases. Positive CE diagnosis occurred in 63% of cases. The preparation method did not significantly affect the quality of bowel preparation for CE. The overall incomplete rate was 33%, and was high in the elderly and those with poor bowel preparation. Capsule retention was 3% and high in patients with small bowel tumors and Crohn's disease and in children under 10 years of age. CONCLUSIONS: CE is a valuable technique; while the overall detection rate is high, incompletion and retention rates are also relatively high. CE should be carefully considered in the elderly and children less than 10 years of age, as well as in patients with small bowel tumors and Crohn's disease.
Aged ; Capsule Endoscopy* ; Child ; Crohn Disease ; Diagnosis ; Hemorrhage ; Humans ; Intestine, Small

BACKGROUND/AIMS: Capsule endoscopy (CE) has become an important tool for the diagnosis of small bowel disease. Although CE does not require the skill of endoscope insertion, the images should be interpreted by a person with experience in assessing images of the gastrointestinal mucosa. This investigation aimed to document the number of cases needed by trainees to gain the necessary experience for CE competency. METHODS: Fifteen cases were distributed to 12 trainees with no previous experience of CE during their gastroenterology training as clinical fellows. Twelve trainees and an expert were asked to read CE images from one patient each week for 15 weeks. The diagnosis was reported using five categories (no abnormalities detected, small bowel erosion or ulcer, small bowel tumor, Crohn disease, and active small bowel bleeding with no identifiable source). We then examined, using the kappa coefficient, how the degree of mean agreements between the trainees and the expert changed as the training progressed each week. RESULTS: The agreement rate of CE diagnosis increased as the frequencies of interpretation increased. Most of the mean kappa coefficients were >0.60 and >0.80 after week 9 and 11, respectively. CONCLUSIONS: Experience with approximately 10 cases of CE is appropriate for trainees to attain CE competency.
Capsule Endoscopy* ; Crohn Disease ; Diagnosis ; Endoscopes ; Gastroenterology ; Hemorrhage ; Humans ; Learning Curve* ; Learning* ; Mucous Membrane ; Ulcer

Crohn's disease (CD) is a chronic inflammatory bowel disease (IBD) with uncertain etiopathogenesis. CD can involve any site of gastrointestinal tract from the mouth to anus and is associated with serious complications such as bowel strictures, perforations, and fistula formation. The incidence and prevalence rates of CD in Korea are still lower than those of Western countries, but have been rapidly increasing during the past decades. Although there are no definitive curative modalities for CD, various medical and surgical therapies are currently applied for diverse clinical situations of CD. However, a lot of decisions on the management of CD are made depending on the personal experiences and personal dicision of physicians. To suggest preferable approaches to diverse problems of CD and to minimize the variations according to physicians, guidelines for the management of CD are needed. Therefore, IBD Study Group of the Korean Association for the Study of the Intestinal Diseases has set out to develop the guidelines for the management of CD in Korea. These guidelines were developed using the adaptation methods and encompass the treatment of inflammatory disease, stricturing disease, and penetrating disease. The guidelines also cover the indication of surgery, prevention of recurrence after surgery, and CD in pregnancy and lactation. These are the first Korean guidelines for the management of CD and the update with further scientific data and evidences is needed.
6-Mercaptopurine/analogs & derivatives/therapeutic use ; Anti-Inflammatory Agents/therapeutic use ; Antibodies, Monoclonal/therapeutic use ; Antimetabolites, Antineoplastic/therapeutic use ; Budesonide/therapeutic use ; Crohn Disease/*drug therapy/pathology ; Databases, Factual ; Female ; Fistula/therapy ; Humans ; Intestinal Perforation/surgery/therapy ; Male ; Mesalamine/therapeutic use ; Methotrexate/therapeutic use ; Prednisolone/therapeutic use ; Pregnancy ; Recurrence ; Risk Factors ; Severity of Illness Index ; Sulfasalazine/therapeutic use