Crohn’s disease (CD) is a relapsing and progressive condition characterized by diarrhea, abdominal pain, weight loss, and hematochezia that results in serious complications such as perforations, fistulas, and abscesses. Various medications, interventions, and surgical treatments have been used to treat CD. The Korean guidelines for CD management were distributed in 2012 and revised in 2017 by the Inflammatory Bowel Disease (IBD) Research Group of the Korean Association for the Study of Intestinal Diseases. Substantial progress in mucosal immunologic research has elucidated the pathophysiology of IBD, leading to development of biological agents for treatment of CD. The first developed biologic agent, tumor necrosis factor-α agents, were shown to be efficacious in CD, heralding a new era in management of CD. Subsequently, vedolizumab, a monoclonal antibody against integrin α4β7, and ustekinumab, a human monoclonal antibody that inhibits the common p40 subunit of interleukin-12 and interleukin-23, were both approved for clinical use and are efficacious and safe for both induction and maintenance of remission in moderate-to-severe CD patients. Moreover, a recent study showed the non-inferiority of CT-P13, an infliximab biosimilar, compared with infliximab in CD patients. The third Korean guidelines for CD management provide updated information regarding treatment of moderate-to-severe CD patients with biologic agents.

Background/Aims: The short- and long-term effects of adalimumab (ADA) on Korean patients with intestinal Behcet’s disease (BD) for remain unclear. Therefore, a multicenter study was performed to evaluate the efficacy and safety of ADA in Korean patients with intestinal BD in a real-world setting. Methods: The medical records of 67 patients with BD prescribed ADA between January 2012 and December 2020 at five referral centers in Korea were retrospectively analyzed and the safety and efficacy of ADA within 52 weeks were assessed. To evaluate the clinical efficacy of ADA, the Disease Activity Index for Intestinal BD (DAIBD) and representative blood biochemical markers were compared at 0, 12, 24, and 52 weeks of ADA treatment. Results: During the follow-up period of 52 weeks, 46 patients continued ADA treatment. The cumulative drug survival rate was 83.5%. The DAIBD score decreased over the study period (p < 0.001). Moreover, the erythrocyte sedimentation rate, serum C-reactive protein levels, and serum albumin levels significantly improved at 12, 24, and 52 weeks of ADA treatment (all, p <0.05). Conclusions As ADA is effective for refractory intestinal BD with few safety concerns in real-world situations, it is a potential treatment option for Korean patients with intestinal BD.

Background/Aims: Chronic enteropathy associated with SLCO2A1 gene (CEAS), an inherited disease characterized by nonspecific intestinal ulcers, has emerged in the Japanese population via loss-of-function mutations in the SLCO2A1 gene. We aimed to investigate the clinical and genetic characteristics of Korean patients diagnosed with CEAS. Methods: From July 2018 to July 2021, we performed Sanger sequencing of the SLCO2A1 gene in 46 patients with chronic intestinal ulcers. CEAS was confirmed based on known SLCO2A1 mutations. We summarized the clinical characteristics of patients with confirmed CEAS. Results: Fourteen out of 46 patients (30.4%) had genetically confirmed CEAS, and two SLCO2A1variants were detected (splicing site variant c.940+1G>A and nonsense mutation [p.R603X] in SLCO2A1). Twelve patients (85.7%) were females and the median age at diagnosis of CEAS was 44.5 years. All patients presented with abdominal pain, and 13 patients (92.9%) presented with anemia (median hemoglobin, 9.6 g/dL). Ten patients (71.4%) had hypoalbuminemia (median, 2.7 g/dL). The most commonly involved site was the ileum (13/14, 92.9%). Manifestations of primary hypertrophic osteoarthropathy (PHO), such as digital clubbing, pachydermia, and periostosis were observed in five patients (28.6%) and two male patients and one female patient satisfied all major PHO diagnostic criteria. Conclusions The clinical and genetic characteristics of Korean patients with confirmed CEAS were similar to those reported in the literature. CEAS should be considered in the differential diagnosis for patients with unexplained chronic nonspecific ulcers of the small intestine.

Background/Aims: The long-term course of Crohn’s disease (CD) has never been evaluated in non-Caucasian population-based cohorts. The aim of the present study was to evaluate the longterm prognosis of Korean CD patients in the well-defined population-based Songpa-Kangdong inflammatory bowel disease cohort. Methods: Outcomes of disease and their predictors were evaluated for 418 patients diagnosed with CD between 1986 and 2015. Results: During a median of 123 months, systemic corticosteroids, thiopurines, and anti-tumor necrosis factor (TNF) agents were administered to 58.6%, 81.3%, and 37.1% of patients, respectively. Over time, the cumulative probability of starting corticosteroids significantly decreased (p=0.001), whereas that of starting thiopurines and anti-TNFs significantly increased (both p<0.001). The cumulative probability of behavioral progression was 54.5% at 20 years, and it significantly decreased during the anti-TNF era. Intestinal resection was required for 113 patients (27.0%). The cumulative probabilities of intestinal resection at 1, 5, 10, 20, and 25 years after CD diagnosis were 12.7%, 16.5%, 23.8%, 45.1%, and 51.2%, respectively. Multivariable Cox regression analysis identified stricturing behavior at diagnosis (adjusted hazard ratio [aHR], 2.70; 95% confidence interval [CI], 1.55 to 4.71), penetrating behavior at diagnosis (aHR, 11.15; 95% CI, 6.91 to 17.97), and diagnosis of CD during the anti-TNF era (aHR, 0.51; 95% CI, 0.35 to 0.76) as independently associated with intestinal resection. The standardized mortality ratio among CD patients was 1.36 (95% CI, 0.59 to 2.68). Conclusions The long-term prognosis of Korean patients with CD is at least as good as that of Western CD patients, as indicated by the low intestinal resection rate. Moreover, behavioral progression and intestinal resection rates have decreased over the past 3 decades.

Background/Aims: We aimed to evaluate the clinical characteristics and long-term prognosis of elderly-onset ulcerative colitis (EOUC) in Korean patients over a 30-year period using a wellestablished population-based cohort in the Songpa-Kangdong district of Seoul, Korea. Methods: Clinical characteristics and prognosis were compared between two groups: EOUC,defined as UC diagnosed in individuals aged ≥60 years and non-EOUC (N-EOUC), defined asUC diagnosed in individuals aged 18 to 59 years. Results: We identified 99 patients with EOUC (10.3%) and 866 patients with N-EOUC (89.7%) between 1986 and 2015. During the median follow-up of 104.5 months, the overall exposure tomedications was comparable between patients with EOUC and N-EOUC (p=0.091 for corticosteroids, p=0.794 for thiopurines, and p=0.095 for anti-tumor necrosis factor agents). The cumula-tive risks of disease outcomes were also comparable between patients with EOUC and N-EOUC (22.4% vs 30.4% for proximal disease extension [p=0.351], 11.9% vs 18.1% for hospitalization [p=0.240], and 2.3% vs 1.8% for colectomy [p=0.977]) at 10 years after diagnosis. Multivariate Cox regression analysis revealed that corticosteroid use at diagnosis was an independent predic-tor of proximal disease extension (hazard ratio [HR], 6.216; 95% confidence interval [CI], 1.314 to 28.826) and hospitalization (HR, 11.241; 95% CI, 3.027 to 41.742) in patients with EOUC. Conclusions In this population-based study from Korea, the pattern of medication use seemed comparable between the EOUC and N-EOUC groups. Moreover, patients with EOUC and those with N-EOUC have a similar disease course in terms of proximal disease extension, hospitaliza-tion, and colectomy.

Background: and Purpose We aimed to develop a model predicting early recanalization after intravenous tissue plasminogen activator (t-PA) treatment in large-vessel occlusion. Methods: Using data from two different multicenter prospective cohorts, we determined the factors associated with early recanalization immediately after t-PA in stroke patients with large-vessel occlusion, and developed and validated a prediction model for early recanalization. Clot volume was semiautomatically measured on thin-section computed tomography using software, and the degree of collaterals was determined using the Tan score. Follow-up angiographic studies were performed immediately after t-PA treatment to assess early recanalization. Results: Early recanalization, assessed 61.0±44.7 minutes after t-PA bolus, was achieved in 15.5% (15/97) in the derivation cohort and in 10.5% (8/76) in the validation cohort. Clot volume (odds ratio [OR], 0.979; 95% confidence interval [CI], 0.961 to 0.997; P=0.020) and good collaterals (OR, 6.129; 95% CI, 1.592 to 23.594; P=0.008) were significant factors associated with early recanalization. The area under the curve (AUC) of the model including clot volume was 0.819 (95% CI, 0.720 to 0.917) and 0.842 (95% CI, 0.746 to 0.938) in the derivation and validation cohorts, respectively. The AUC improved when good collaterals were added (derivation cohort: AUC, 0.876; 95% CI, 0.802 to 0.950; P=0.164; validation cohort: AUC, 0.949; 95% CI, 0.886 to 1.000; P=0.036). The integrated discrimination improvement also showed significantly improved prediction (0.097; 95% CI, 0.009 to 0.185; P=0.032). Conclusions The model using clot volume and collaterals predicted early recanalization after intravenous t-PA and had a high performance. This model may aid in determining the recanalization treatment strategy in stroke patients with large-vessel occlusion.

Background/Aims: We aimed to evaluate the clinical characteristics and long-term prognosis of elderly-onset ulcerative colitis (EOUC) in Korean patients over a 30-year period using a wellestablished population-based cohort in the Songpa-Kangdong district of Seoul, Korea. Methods: Clinical characteristics and prognosis were compared between two groups: EOUC,defined as UC diagnosed in individuals aged ≥60 years and non-EOUC (N-EOUC), defined asUC diagnosed in individuals aged 18 to 59 years. Results: We identified 99 patients with EOUC (10.3%) and 866 patients with N-EOUC (89.7%) between 1986 and 2015. During the median follow-up of 104.5 months, the overall exposure tomedications was comparable between patients with EOUC and N-EOUC (p=0.091 for corticosteroids, p=0.794 for thiopurines, and p=0.095 for anti-tumor necrosis factor agents). The cumula-tive risks of disease outcomes were also comparable between patients with EOUC and N-EOUC (22.4% vs 30.4% for proximal disease extension [p=0.351], 11.9% vs 18.1% for hospitalization [p=0.240], and 2.3% vs 1.8% for colectomy [p=0.977]) at 10 years after diagnosis. Multivariate Cox regression analysis revealed that corticosteroid use at diagnosis was an independent predic-tor of proximal disease extension (hazard ratio [HR], 6.216; 95% confidence interval [CI], 1.314 to 28.826) and hospitalization (HR, 11.241; 95% CI, 3.027 to 41.742) in patients with EOUC. Conclusions In this population-based study from Korea, the pattern of medication use seemed comparable between the EOUC and N-EOUC groups. Moreover, patients with EOUC and those with N-EOUC have a similar disease course in terms of proximal disease extension, hospitaliza-tion, and colectomy.

Background: and Purpose We aimed to develop a model predicting early recanalization after intravenous tissue plasminogen activator (t-PA) treatment in large-vessel occlusion. Methods: Using data from two different multicenter prospective cohorts, we determined the factors associated with early recanalization immediately after t-PA in stroke patients with large-vessel occlusion, and developed and validated a prediction model for early recanalization. Clot volume was semiautomatically measured on thin-section computed tomography using software, and the degree of collaterals was determined using the Tan score. Follow-up angiographic studies were performed immediately after t-PA treatment to assess early recanalization. Results: Early recanalization, assessed 61.0±44.7 minutes after t-PA bolus, was achieved in 15.5% (15/97) in the derivation cohort and in 10.5% (8/76) in the validation cohort. Clot volume (odds ratio [OR], 0.979; 95% confidence interval [CI], 0.961 to 0.997; P=0.020) and good collaterals (OR, 6.129; 95% CI, 1.592 to 23.594; P=0.008) were significant factors associated with early recanalization. The area under the curve (AUC) of the model including clot volume was 0.819 (95% CI, 0.720 to 0.917) and 0.842 (95% CI, 0.746 to 0.938) in the derivation and validation cohorts, respectively. The AUC improved when good collaterals were added (derivation cohort: AUC, 0.876; 95% CI, 0.802 to 0.950; P=0.164; validation cohort: AUC, 0.949; 95% CI, 0.886 to 1.000; P=0.036). The integrated discrimination improvement also showed significantly improved prediction (0.097; 95% CI, 0.009 to 0.185; P=0.032). Conclusions The model using clot volume and collaterals predicted early recanalization after intravenous t-PA and had a high performance. This model may aid in determining the recanalization treatment strategy in stroke patients with large-vessel occlusion.

In 2020, the novel coronavirus disease 2019 (COVID-19) began to spread worldwide and remains an ongoing medical challenge. This case series reports on the clinical features and characteristics of patients with inflammatory bowel disease (IBD) and confirmed COVID-19 infection. From February 2020 to March 2021, nine patients with IBD had confirmed COVID-19 across four hospitals in Korea. The median age at COVID-19 diagnosis was 42 years. Six patients were male, and seven patients had ulcerative colitis (UC). No patients required oxygen therapy, intensive care unit hospitalizations, or died. The most common symptom was fever, and gastrointestinal (GI) symptoms developed as diarrhea in five patients with UC. Oral steroids were used to combat UC aggravation in two patients. In this case series of nine IBD patients diagnosed with COVID-19 in Korea, the clinical presentation was predominately a mild respiratory tract infection. Most patients with UC developed new GI symptoms including diarrhea.

Background: Cardiac arrest during or after office-based cosmetic surgery is rare, and little is known about its prognosis. We assessed the clinical outcomes of patients who developed cardiac arrest during or after cosmetic surgery at office-based clinics. Methods: Between May 2009 and May 2016, 32 patients who developed cardiac arrest during or after treatment at cosmetic surgery clinics were consecutively enrolled. We compared clinical outcomes, including complications, between survivors (n=19) and non-survivors (n=13) and attempted to determine the prognostic factors of mortality. Results: All 32 of the patients were female, with a mean age of 30.40±11.87 years. Of the 32 patients, 13 (41%) died. Extracorporeal life support (ECLS) was applied in a greater percentage of non-survivors than survivors (92.3% vs. 47.4%, respectively; p=0.009). The mean duration of in-hospital cardiopulmonary resuscitation (CPR) was longer for the non-survivors than the survivors (31.55±33 minutes vs. 7.59±9.07 minutes, respectively; p=0.01).The mean Acute Physiology and Chronic Health Evaluation score was also higher among non-survivors than survivors (23.85±6.68 vs. 16.79±7.44, respectively; p=0.01). No predictor of death was identified in the patients for whom ECLS was applied. Of the 19 survivors, 10 (52.6%) had hypoxic brain damage, and 1 (5.3%) had permanent lower leg ischemia.Logistic regression analyses revealed that the estimated glomerular filtration rate was a predictor of mortality. Conclusion Patients who developed cardiac arrest during or after cosmetic surgery at office-based clinics experienced poor prognoses, even though ECLS was applied in most cases. The survivors suffered serious complications. Careful monitoring of subjects and active CPR (when necessary) in cosmetic surgery clinics may be essential.