Background/Aims: Krebs von den Lungen-6 (KL-6) is associated with prognosis in patients with COVID-19. However, there is limited data on the correlation between the prognosis of COVID-19 and varying KL-6 levels at different time points. We investigated the optimal cutoff values of the initial and peak serum KL-6 levels to predict mortality and evaluated their correlation with mortality. Methods: This retrospective cohort study collected data on serially collected serum KL-6 levels in patients hospitalized with COVID-19 between October 2020 and January 2022 at a single tertiary hospital in South Korea. The area under the receiver operating characteristic curve and Youden index were used to determine the cutoff points for the initial and peak KL-6 levels that best predicted 30-day mortality. The association between the initial and peak KL-6 values was assessed by univariate and multivariate logistic regression models. Results: A total of 349 patients were included in this study. The mean initial and peak KL-6 levels were significantly higher in the non-survivor group than in the survivor group. The initial and peak KL-6 values that best predicted 30-day mortality were 491.85 U/mL and 660.05 U/mL, respectively. An initial KL-6 level greater than 491.85 U/mL and a peak KL-6 level greater than 660.05 U/mL were significantly associated with 30-day mortality. Conclusions The initial and peak levels of KL-6 were significantly associated with 30-day mortality in hospitalized patients with COVID-19. These findings suggest that serially monitoring blood KL-6 levels could be a valuable prognostic indicator for COVID-19.

Background/Aims: Portal vein thrombosis (PVT) frequently occurs in patients with inflammatory bowel disease (IBD), particularly when influenced by factors such as abdominal infections, IBD flare-ups, or surgical procedures. The implications of PVT range from immediate issues such as intestinal ischemia to long-term concerns including portal hypertension and its complications. However, there is a notable gap in comprehensive studies on PVT in IBD, especially with the increasing incidence of IBD in Asia. This research aimed to evaluate the clinical features and outcomes of PVT in patients with IBD at a leading hospital in South Korea. Methods: This retrospective analysis reviewed adult patients diagnosed with both IBD and PVT from 1989 to 2021 at a renowned South Korean medical center. The study focused on patient characteristics, specifics of PVT, administered treatments, and outcomes, all confirmed through enhanced CT scans. Results: A total of 78 patients met the study’s criteria. Notably, only 20.5% (16/78) were treated with oral anticoagulants; however, a vast majority (96.2%; 75/78) achieved complete radiographic resolution (CRR). When comparing patients receiving anticoagulants to those who did not, a significant preference for anticoagulant use was observed in cases where the main portal vein was affected, as opposed to just the left or right veins (p = 0.006). However, multivariable analysis indicated that neither anticoagulant use nor previous surgeries significantly impacted CRR. Conclusions Patients with IBD and PVT generally had favorable outcomes, regardless of anticoagulant use.

Objective: To evaluate the safety and efficacy of coil embolization of venous segments in patients with Type IIa pelvic arteriovenous malformations (AVMs). Materials and Methods: A retrospective study was performed on 13 patients (median age, 43 years, range 20–62 years, 7 males) who underwent transvenous coil embolization for Type IIa pelvic AVM (characterized by multiple arterioles shunting to focal venous segments of a single draining vein) without the use of additional liquid embolic agents from March 2017 to February 2023. Treatment outcomes were analyzed based on clinical evaluations, post angiography findings, and follow-up CT. Results: Fourteen procedures were performed on 13 patients. Except in one patient, all treatments were completed in a single session. Transvenous access was employed in 10 procedures, whereas direct puncture was used in four sessions. The embolization procedures used an average of 55.7 ± 58.5 coils (range, 7–238) and lasted an average of 127.3 ± 39.5 minutes.The technical success rate was 92.9% (of 13/14). All patients reported symptom improvement. Follow-up CT scans showed complete occlusion of the AVM without recurrence in ten of the 13 patients. There was one minor adverse event: a small retroperitoneal hemorrhage, likely related to direct puncture, which resolved spontaneously. No other adverse events were observed. Conclusion Coil embolization of the draining vein segment, without the use of additional liquid embolic agents is a safe and effective method for managing Type IIa pelvic AVM.

Purpose: This multicenter, open-label, phase II trial evaluated the efficacy and safety of bortezomib combined with dexamethasone for the treatment of relapsed/refractory cutaneous T-cell lymphoma (CTCL) in previously treated patients across 14 institutions in South Korea. Materials and Methods: Between September 2017 and July 2020, 29 patients with histologically confirmed CTCL received treatment, consisting of eight 4-week cycles of induction therapy followed by maintenance therapy, contingent upon response, for up to one year. The primary endpoint was the proportion of patients achieving an objective global response. Results: Thirteen of the 29 patients (44.8%) achieved an objective global response, including two complete responses. The median progression-free survival (PFS) was 5.8 months, with responders showing a median PFS of 14.0 months. Treatment-emergent adverse events were generally mild, with a low incidence of peripheral neuropathy and hematologic toxicities. Despite the trend toward shorter PFS in patients with higher mutation burdens, genomic profiling before and after treatment showed no significant emergence of new mutations indicative of disease progression. Conclusion This study supports the use of bortezomib and dexamethasone as a viable and safe treatment option for previously treated CTCL, demonstrating substantial efficacy and manageability in adverse effects. Further research with a larger cohort is suggested to validate these findings and explore the prognostic value of mutation profiles.

Background: This study aimed to compare the intraoperative stability and early clinical outcomes of 40-mm diameter dual mobility (DM)-total hip arthroplasty (THA) with 36-mm ceramic head (large head) THA in active elderly patients with hip fractures. Methods: A prospective randomized controlled trial was conducted from May 2022 to December 2022. Inclusion criteria were as follows: age ≥ 60 years, displaced femoral neck fracture, Koval grade 1 or 2, planned 54-mm acetabular component, and over 1-year follow-up. Intraoperative stability tests were performed on all patients (internal rotation at 45°, 60°, and 90° of hip fracture). Functional outcomes (Harris Hip Score and University of California, Los Angeles [UCLA] Score) were evaluated at 6 weeks and 3 months postoperatively. Gait analysis using artificial intelligence (AI) techniques was conducted at 3 months postoperatively. Results: The study included 36 DM-THA patients (mean age, 69.6 ± 2.2 years; 44% women) and 37 large head THA patients (mean age, 69.6 ± 1.2 years; 64% women). No statistically significant differences were observed in functional outcomes and hip range of motion between the 2 groups. However, there was a significant difference in the gait speed and stance-swing phase of the large head THA group and the DM-THA group: the DM-THA group demonstrated superior gait speed (2.85 ± 0.83 kph vs. 2.04 ± 1.04 kph, p = 0.003) and higher stance phase ratios (operated side: 63.57% ± 3.82% vs. 48.19% ± 5.50%, p < 0.001; opposite side: 62.77% ± 2.27% vs. 49.93% ± 6.94%, p < 0.001). In the stability test at 90° of hip flexion, the DM-THA group had a measurement of 48.40° ± 5.17°, while the large head THA group had a measurement of 30.94° ± 2.98° (p = 0.012). Despite the lack of statistical significance, the intraoperative stability test showed the dislocation angle was notably different between the groups in the hip flexion position of 60° (51.60° ± 6.09° in the DM-THA group and 40.00° ± 2.80° in the large head THA group, p = 0.072). Conclusions Superior results were observed in the intraoperative stability test and early recovery of gait after DM-THA compared to large head THA. We believe that DM-THA can be a useful surgical option for THA in elderly patients with hip fractures.

Alzheimer disease (AD) diagnosis is confirmed using a medley of modalities, such as the detection of amyloid-β (Aβ) neuritic plaques and neurofibrillary tangles with positron electron tomography (PET) or the appraisal of irregularities in cognitive function with examinations. Although these methods have been efficient in confirming AD pathology, the rising demand for earlier intervention during pathogenesis has led researchers to explore the diagnostic potential of fluid biomarkers in cerebrospinal fluid (CSF) and plasma. Since CSF sample collection is invasive and limited in quantity, biomarker detection in plasma has become more attractive and modern advancements in technology has permitted more efficient and accurate analysis of plasma biomolecules. In this study, we found that a composite of standard factors, Aβ40 and total tau levels in plasma, divided by the variation factor, plasma Aβ42 level, provide better correlation with amyloid neuroimaging and neuropsychological test results than a level comparison between total tau and Aβ42 in plasma. We collected EDTA-treated blood plasma samples of 53 subjects, of randomly selected 27 AD patients and 26 normal cognition (NC) individuals, who received amyloid-PET scans for plaque quantification, and measured plasma levels of Aβ40, Aβ42, and total tau with digital enzyme-linked immunosorbent assay (ELISA) in a blinded manner. There was difficulty distinguishing AD patients from controls when analyzing biomarkers independently. However, significant differentiation was observed between the two groups when comparing individual ratios of total-tau×Aβ40/Aβ42. Our results indicate that collectively comparing fluctuations of these fluid biomarkers could aid in monitoring AD pathogenesis.

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: Small bowel capsule endoscopy (SBCE) has become the standard for initial evaluation in the diagnosis of small bowel lesions. Although optimal visualization of the mucosa is important, patients experience difficulty in consuming a large volume of bowel preparation agents. This study aimed to compare the efficacy and safety of 1-L polyethylene glycol (PEG) with ascorbic acid (AA) and 2-L PEG with AA. Methods: In this prospective, multicenter, non-inferiority study, patients who received SBCE were randomly assigned to consume 1-L PEG with AA or 2-L PEG with AA for small bowel preparation. The primary outcome was adequate small bowel visibility quality (SBVQ). The secondary outcomes included diagnostic yield, cecal complete rate, and adverse events. Results: One hundred and forty patients were enrolled in this study, 70 patients per group. In the per-protocol analysis, there were no significant differences in the adequate SBVQ rate (94.0% vs 94.3%; risk difference, –0.3; 95% confidence interval, –8.1 to 7.6; p=1.000), diagnostic yield rate (49.3% vs 48.6%, p=0.936), or cecal complete rate (88.1% vs 92.9%, p=0.338) between the 1-L PEG with AA group and 2-L PEG with AA group. The incidence of adverse events did not differ significantly between the groups (12.9% vs 11.9%, p=0.871). Conclusions One liter-PEG with AA is not inferior to 2-L PEG with AA in terms of adequate SBVQ for SBCE. One liter-PEG with AA can be recommended as the standard method for bowel cleansing for SBCE.

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.

Objective: To evaluate the safety and efficacy of coil embolization of venous segments in patients with Type IIa pelvic arteriovenous malformations (AVMs). Materials and Methods: A retrospective study was performed on 13 patients (median age, 43 years, range 20–62 years, 7 males) who underwent transvenous coil embolization for Type IIa pelvic AVM (characterized by multiple arterioles shunting to focal venous segments of a single draining vein) without the use of additional liquid embolic agents from March 2017 to February 2023. Treatment outcomes were analyzed based on clinical evaluations, post angiography findings, and follow-up CT. Results: Fourteen procedures were performed on 13 patients. Except in one patient, all treatments were completed in a single session. Transvenous access was employed in 10 procedures, whereas direct puncture was used in four sessions. The embolization procedures used an average of 55.7 ± 58.5 coils (range, 7–238) and lasted an average of 127.3 ± 39.5 minutes.The technical success rate was 92.9% (of 13/14). All patients reported symptom improvement. Follow-up CT scans showed complete occlusion of the AVM without recurrence in ten of the 13 patients. There was one minor adverse event: a small retroperitoneal hemorrhage, likely related to direct puncture, which resolved spontaneously. No other adverse events were observed. Conclusion Coil embolization of the draining vein segment, without the use of additional liquid embolic agents is a safe and effective method for managing Type IIa pelvic AVM.