Background/Aims: Rectal hyposensitivity (RH), as defined by the London Classification, has been linked to sensory dysfunction caused by diabetes mellitus and Parkinson’s disease (PD); however, its clinical interpretation has not been sufficiently validated. In this study, we aim to explore the correlations between rectal sensory thresholds and the clinical characteristics of patients with functional defecatory disorders. Methods: We reviewed data from patients who underwent high-resolution anorectal manometry and acquired their clinical characteristics using a standardized questionnaire. The associations between RH based on either 1 (borderline RH) or 2 (RH) abnormal rectal sensory thresholds and patients’ clinical and demographic characteristics were analyzed using linear and logistic regression models in the overall sex-stratified populations. Results: We enrolled 2540 patients, of whom 1046 (41.2%) were men. Overall, 150 (5.9%) patients were diagnosed with RH, whereas 422 (16.6%) had borderline RH. Multivariate linear regression analysis revealed that the Cleveland Clinic Constipation Score (CCCS) increased linearly with the increase in the number of abnormal rectal sensory thresholds (effect per threshold: 0.900 [standard deviation: 0.188]). Upon stratification by sex, borderline RH was positively associated with diabetes mellitus, PD, and CCCS (adjusted odds ratio [aOR] = 2.11, 95% confidence interval [1.08, 4.15]; aOR = 1.49 [1.03, 2.14]; aOR = 1.03 [1.01, 1.05], respectively) in women. However, RH was positively associated with only the CCCS. Conclusions Defining RH based on 1 or more abnormal sensory thresholds showed better clinical correlation with patient characteristics. However, further prospective studies are needed to validate these findings before proposing revisions to the current London classification criteria.

Background/Aims: Post-infectious irritable bowel syndrome (PI-IBS) is characterized by chronic gastrointestinal symptoms that arise following an episode of infectious enteritis. The incidence rates vary, ranging from 5% to 32% and the risk factors are not well known. We aim to investigate the incidence and risk factors of PI-IBS in enteritis patients admitted to university hospitals in Korea. Methods: This multi-center prospective study was conducted in patients hospitalized for infectious enteritis. Each patient underwent 1 outpatient visit and 3 telephone surveys during the first year after discharge to determine if PI-IBS occurred within the follow-up period. Results: In the 3-month survey, 7 out of 354 patients (2%) were diagnosed with PI-IBS, and after 1 year, only 1 patient met the criteria for IBS.No statistically significant difference was found between the PI-IBS group and the non-PI-IBS group in terms of age, sex, underlying diseases, medication history, gastrointestinal symptoms, enteritis location, causative strain, hospitalization and treatment periods, and laboratory findings. Female sex (P = 0.003), enteropathogenic Escherichia coli (EPEC) infection (P = 0.044), and a longer total treatment period (P = 0.018) were independent risk factors for diarrhea lasting ≥ 3 months after enteritis. Conclusions The incidence of PI-IBS in Korea was relatively low, and most cases improved over time. No risk factors associated with the development of PI-IBS were found. However, persistent diarrhea after enteritis was associated with female sex, EPEC infection, and severe or long-lasting enteritis. IBS symptoms may persist after severe enteritis but usually improve with time.

Background: Decreased acetabular version and posterior acetabular coverage of the femoral head have been regarded as the leading causes of sport-related posterior hip dislocation or subluxation. This study aimed to examine the posterior acetabular coverage of the femoral head in 21 patients who sustained posterior hip dislocation or subluxation during sport activities. Methods: The anterior and posterior acetabular rims on 3-dimensional computed tomography (3D-CT) images were delineated on the normal side in these patients. Radiologic signs, including crossover and posterior wall signs, were examined. The fracture center level (FCL) of the posterior acetabular wall was identified on axial CT images of the injured hip and the level was marked on the normal side. The difference in the femoral head coverage by posterior and anterior acetabular rims was measured by measuring the horizontal distance between anterior and posterior acetabular rims at the FCL (posterior-anterior [P-A] index). The acetabular version was measured at the femoral head and FCL using axial CT images of the normal side. Femoral head coverage by the posterior acetabular wall on the normal side was measured using 3D-CT (areal coverage). Results: The crossover and posterior wall signs were positive in 14 and 10 patients, respectively, in 3D-CT images. The FCL was evenly distributed in the proximal half of the posterior acetabular wall. Seven patients had a P-A index of ≤ 0, and all were positive for the crossover sign. The anterior acetabular rim was relatively prominent in these patients. The acetabular version was lower at the FCL than at the femoral head center (p < 0.001). The proximal half areal coverage of the posterior acetabular wall was significantly smaller than the whole areal coverage (p = 0.003). Conclusions Superior–posterior coverage of the femoral head by the posterior acetabular wall was insufficient in patients who sustained hip posterior dislocation or subluxation during sports activities.

Background/Aims: Inaccurate prediction of lymph node metastasis (LNM) may lead to unnecessary surgery following endoscopic resection of T1 colorectal cancer (CRC). We aimed to validate the usefulness of artificial intelligence (AI) models for predicting LNM in patients with T1 CRC. Methods: We analyzed the clinical data, laboratory results, pathological reports, and endoscopic findings of patients who underwent radical surgery for T1 CRC. We developed AI models to predict LNM using four algorithms: regularized logistic regression classifier (RLRC), random forest classifier (RFC), CatBoost classifier (CBC), and the voting classifier (VC). Four histological factors and four endoscopic findings were included to develop AI models. Areas under the receiver operating characteristics curves (AUROCs) were measured to distinguish AI model performance in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines. Results: Among 1,386 patients with T1 CRC, 173 patients (12.5%) had LNM. The AUROC values of the RLRC, RFC, CBC, and VC models for LNM prediction were significantly higher (0.673, 0.640, 0.679, and 0.677, respectively) than the 0.525 suggested in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines (vs RLRC, p<0.001; vs RFC, p=0.001; vs CBC, p<0.001; vs VC, p<0.001). The AUROC value was similar between T1 colon versus T1 rectal cancers (0.718 vs 0.615, p=0.700). The AUROC value was also similar between the initial endoscopic resection and initial surgery groups (0.581 vs 0.746, p=0.845). Conclusions AI models trained on the basis of endoscopic findings and pathological features performed well in predicting LNM in patients with T1 CRC regardless of tumor location and initial treatment method.

Background/Aims: The study investigated the incidence, risk factors, and clinical outcomes of chronic antibiotic-refractory pouchitis (CARP) in Korean patients with ulcerative colitis (UC). Methods: This single-center retrospective study included patients with UC who underwent total proctocolectomy with ileal pouch-anal anastomosis at the Asan Medical Center in Korea between January 1987 and December 2022. The primary outcomes were endoscopic remission and pouch failure. The Cox’s proportional hazard model was used to identify the risk factors for CARP. Results: The clinical data of 232 patients were analyzed. The most common cause of surgery was steroid refractoriness (50.9%), followed by dysplasia/colorectal cancer (26.7%). Among 74 patients (31.9%) with chronic pouchitis (CP), 31 (13.4%) had CARP, and 43 (18.5%) had chronic antibiotic-dependent pouchitis (CADP). The most frequent endoscopic phenotype was focal inflammation of the pouch (CP, 47.3%; CARP, 35.5%; CADP, 55.8%). Patients with CARP were less likely to use concomitant probiotics than patients with CADP (29.0% vs 72.1%, p<0.01). The endoscopic remission rate of CP, CARP, and CADP was 14.9%, 9.7%, and 18.6%, respectively.The pouch failure rate associated with CP, CARP, and CADP was 13.5%, 16.1%, and 11.6%, respectively. Current smoking status (adjusted hazard ratio [aHR], 2.96; 95% confidence interval [CI], 1.27 to 6.90; p=0.01) and previous use of biologics/small molecules (aHR, 2.40; 95% CI, 1.05 to 5.53; p=0.04) were significantly associated with CARP development. Conclusions UC patients who were current smokers and previously used biologics/small molecules had a higher risk of developing CARP. Concomitant use of probiotics was less likely to be associated with CARP development.

Purpose: Myocardial strain imaging is a promising tool for evaluating altered cardiac wall mechanics in thickened myocardium. Circumferential transmural strain difference (cTSD) can be readily measured using feature-tracking magnetic resonance imaging (MRI). This study aimed to explore the correlations between cTSD and other markers of disease in apical hypertrophic cardiomyopathy (ApHCM). Materials and Methods: A retrospective, single-center, case-control study was conducted on patients with ApHCM who underwent 1.5-T or 3.0-T cardiac MRI. Left ventricular (LV) longitudinal and circumferential strains were analyzed using feature-tracking software. cTSD was calculated as the difference between epicardial and endocardial circumferential strains. Global and segmental strains were compared between groups, and correlations between cTSD and LV mass or late gadolinium enhancement (LGE) were analyzed. Results: A total of 29 participants (17 patients with ApHCM, median age 64 years, 71% men; 12 normal controls, median age 55 years, 67% men) were evaluated. Global and segmental cTSD were significantly higher in the ApHCM group than in the normal group from the base to the apex, with the greatest differences at the apex (base 19.6% vs.16.1%, mid 24.5% vs. 16.9%, and apex 36.8% vs. 21.6%, all p < 0.05). Global cTSD showed a moderate positive correlation with indexed LV mass (ρ = 0.599, p = 0.001), while segmental cTSD showed a weak positive correlation with LGE in patients with ApHCM (ρ = 0.239, p < 0.001). Conclusion Segmental cTSD was significantly higher in the ApHCM group than in the normal group, with the greatest difference at the apical segments. This difference was not observed in the full-thickness myocardial circumferential strain. These findings suggest that cTSD may serve as a sensitive imaging biomarker for ApHCM, not only in hypertrophied apex segments but also in non-hypertrophied myocardium.

Purpose: The novel curability criteria for elderly (EL) patients have been proposed to stratify their risk of lymph node metastasis (LNM), following non-curative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). Hence, this study aimed to evaluate the effectiveness of the EL criteria and compare them with those of the well-known eCura system. Materials and Methods: A retrospective analysis was performed on 143 patients who did not meet the curative ESD criteria at a tertiary hospital in Korea between 2011 and 2022. Of these, 102 underwent additional surgery, while 41 were followed up without further treatment. The LNM rates based on the EL and eCura systems were stratified and compared. Results: In the surgery group, 29.4% (30/102) patients were classified as EL-low (EL-L) and 70.2% (72/102) as EL-high (EL-H). The LNM rates (95% confidence interval) were 0.0% (0.0–11.6) and 9.7% (4.0–19.0) for EL-L and EL-H, respectively (P=0.102). EL-L was closely aligned with the eCura low-risk category, with a similar patient proportion (32.4%) and an LNM rate of 0.0% (0.0–10.6). The eCura system classified 94.1% (48/51) of the EL-L patients as lowrisk, with an 86% concordance rate (123/143). Discordant cases included patients with positive vertical margins, but without other risk factors, who were classified as EL-H without LNM. Conclusions Patients with EL-L showed no LNM, and the EL criteria demonstrated high concordance with the eCura system. The EL criteria may be as effective as the eCura system in identifying low-risk patients after non-curative ESD for EGC.

Purpose: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.

Background: Group B Streptococcus (GBS) is one of the leading causes of neonatal earlyonset sepsis, resulting in high mortality and significant comorbidity. Intrapartum penicillin prophylaxis is recommended for pregnant women with GBS colonization to prevent vertical transmission. For pregnant women at high risk of anaphylaxis to penicillin, clindamycin is recommended only if the susceptibility of GBS isolates has been identified. We retrospectively examined the GBS detection rate and clindamycin resistance among Korean women of reproductive age over the last 20 years. Methods: Microbiologic studies using vaginal, vaginal–rectal or vaginal–perianal swabs from female patients 15–49 years of age during 2003–2022 were reviewed. Annual GBS detection rates and clindamycin resistance rates were calculated. The study period was divided into two periods (period 1, 2003–2015; period 2, 2016–2022) based on the introduction of universal culture-based GBS screening in our center in 2016. GBS detection rates and clindamycin resistance rates were compared between the periods using χ2 tests. Results: A total of 14,571 women were tested 16,879 times and GBS was isolated in 1,054 tests (6.2%), with 423 clindamycin-resistant isolates (40.1%). The GBS detection rate increased from 3.4% (301/8,869) in period 1 to 9.4% (2,753/8,010) in period 2 (P < 0.001). Even during period 1, the GBS detection rate was higher in 2009–2015 compared to 2003–2008 (P < 0.001). Clindamycin resistance rates have remained at similar levels since 2009, which were 39.5% (199/301) in period 1 and 40.2% (303/753) in period 2 (P = 0.833). Conclusion This study demonstrated that GBS detection rates in Korean women of reproductive age significantly increased almost three times during the twenty years of the study period, with a persistently high clindamycin resistance rate of up to 40%.