Background: Transthyretin amyloidosis, a protein-misfolding disorder characterized by systemic amyloid deposition, can be classified as wild-type transthyretin amyloidosis (ATTRwt) or hereditary transthyretin amyloidosis (ATTRv), depending on the presence of transthyretin (TTR) gene variants. We examined the genetic distribution of TTR variants in Korean patients diagnosed with ATTRv. Methods: We retrospectively reviewed 801 participants who underwent TTR analysis at Samsung Medical Center from 2012 to 2024. The participants were categorized into two groups: in-house probands or relatives, and externally referred probands or relatives. Results: Pathogenic or likely pathogenic TTR variants were detected in 36 of 165 in-house probands (21.8%), among which D38A was the most frequent variant (50.0%; 18/36), followed by M13dup and E89K (8.3% each). Among referred probands, D38A was predominant (54.5%; 12/22), followed by M13dup (22.7%; 5/22). Cardiac amyloid involvement was the most common manifestation, observed in 97.2% (35/36) of in-house probands with ATTRv, followed by peripheral nervous system (PNS; 94.4%) and autonomic nervous system (ANS; 88.9%) involvement. In contrast, ANS involvement was most prevalent among in-house relatives who underwent organ evaluation (61.5%; 24/39), followed by cardiac (52.1%; 25/48) and PNS (48.7%; 19/39) involvement. Five of the eight in-house relatives harboring M13dup (62.5%) showed organ involvement, primarily in the ANS, supporting the pathogenicity of this variant. Conclusions This study provides the largest single-institution dataset of Korean patients with ATTRv, incorporating systematic organ assessments. The predominance of the unique TTR variants D38A and M13dup delineates a distinct genetic landscape that may facilitate accurate and timely diagnosis of ATTRv in the Korean population.

Objective: This study aimed to evaluate the feasibility, safety, and oncologic outcomes of irreversible electroporation (IRE) using a clustered electrode in patients with locally advanced pancreatic cancer (LAPC). Materials and Methods: In this single-center prospective cohort study, 13 patients with LAPC (median age, 60 years; range, 48–78 years) underwent clustered electrode IRE between September 2022 and September 2024. Patient characteristics, procedural details, and clinical outcomes were recorded. Endpoints included technical success, procedure-related complications, overall survival (OS), and progression-free survival (PFS). Results: Tumors were located in the pancreatic head in four patients (30.8%) and in the body/tail in nine (69.2%). The median tumor size was 2.4 cm (1.5–4.0 cm), and vascular invasion was present in all patients. Technical success was achieved in all patients. Intraoperative IRE was performed in 11 (84.6%) patients, and 2 (15.4%) patients underwent percutaneous IRE. Gastrointestinal bleeding events as major complications occurred in two patients (15.4%) and, both were successfully controlled by embolization. No 60-day mortality was observed. At a median follow-up of 24.5 months (range, 9.9–33.4 months) after IRE, median OS and PFS from IRE were 20.1 and 14.5 months, respectively. Conclusion IRE using clustered electrodes for LAPC appears to be a feasible therapeutic approach, offering reliable technical success and acceptable safety. Survival outcomes are encouraging; however, larger, controlled studies are required.

Background: Baricitinib is one of the front-runners among targeted agents for the treatment of atopic dermatitis (AD). Although many studies have been conducted on the real-world use of baricitinib, the sample size is often small and data is focused primarily on Caucasians. Objective: The objective of this study was to demonstrate the real-world itch-relieving property of baricitinib in adult AD patients in South Korea. Methods: Electronic medical records of AD patients treated with baricitinib at the National Medical Center in Korea from May 2021 to April 2023 were analyzed retrospectively. Results: Seventy patients completed 16 to 52 weeks of baricitinib treatment, with most patients showing mild-to-moderate baseline lesions and moderate-to-severe baseline itch. At Week 16 of baricitinib treatment, there was a 50% reduction in Itch numerical rating scale from baseline, and 50.7% of patients showed 50% improvement in Eczema Area and Severity Index score.The efficacy of baricitinib was also reflected in the patient reported outcomes, with 55%–58% improvements in Patient-Oriented Eczema Measure, Atopic Dermatitis Control Tool, and Dermatology Life Quality Index scores seen within 2 weeks of treatment. No new safety signals were detected in this study. Conclusion Baricitinib treatment for 52 weeks in Korean patients with itch dominant AD confirmed long term effectiveness and safety.

The interstitial cells of Cajal (ICC) generate spontaneous pacemaker activities responsible for producing slow waves in the gut smooth muscles. Prostaglandin E2 (PGE2 ) is one of the most important prostanoids in the gut, playing a crucial role in multiple physiological and pathological processes. Because information regarding the effects of PGE2 on colonic ICC is limited, we investigated the effects of PGE2 and its underlying signaling pathways in murine colonic ICC. Whole-cell patch-clamp recordings and reverse transcription polymerase chain reaction (RT-PCR) analyses were performed to evaluate the effects of PGE2 on mouse colonic ICC. PGE2 had a dual effect on pacemaker potential in the current-clamp mode. RT-PCR data suggested the expression of EP3 and EP4 receptors in colonic ICC. Low PGE2 concentrations induced membrane depolarization and generation of pacemaker activities. And this effect is mimicked by sulprostone (an EP3 agonist). The low PGE2 concentration-induced effect was inhibited by anoctamin-1 (ANO1) or a T-type Ca2+ channel blocker. Conversely, high PGE2 concentrations induced membrane hyperpolarization and blocked pacemaker potential generation. However, this inhibitory effect was blocked by an ATP-sensitive potassium (K ATP) channel blocker but not by other K+ channel blockers. Low concentrations of PGE2 activated EP3 receptors, leading to excitation of pacemaker activity through regulation of ANO1 and T-type Ca2+ channels in colonic ICC. In contrast, higher concentrations of PGE2 activated EP4 receptors and opened ATP-sensitive K+ channels, resulting in inhibition of pacemaker activity in colonic ICC.

Objectives: . Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder that is strongly influenced by obesity, the most important modifiable risk factor. Effective weight management is therefore essential for optimal OSA care. This guideline provides updated, evidence-based recommendations for the evaluation and management of obesity in adults with OSA, incorporating recent advances in lifestyle, pharmacologic, and surgical interventions. Methods: . The Korean Society of Sleep and Breathing convened a multidisciplinary panel. A systematic literature search was performed across major databases through 2025. Evidence was appraised using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, and recommendations were formulated by consensus using the Evidence-to-Decision framework. Results: . Eight statements were developed. Key recommendations include recognizing obesity as a major risk factor; routinely assessing overweight and obesity; and implementing structured weight reduction through diet, exercise, and behavioral therapy. Glucagon-like peptide-1 receptor agonists are recommended when lifestyle interventions are insufficient, and bariatric/metabolic surgery is advised for severe obesity unresponsive to nonsurgical treatment. Weight loss improves the apnea-hypopnea index, symptoms, and cardiometabolic markers and may reduce positive airway pressure needs. Continued follow-up is recommended even after clinical improvement. Conclusion . Weight management is a core component of OSA treatment. This guideline offers practical, evidence-based strategies to support clinicians in delivering effective, obesity-focused care for adults with OSA.

Purpose: To report a nationwide survey on neuroblastoma conducted by the Korean Association of Pediatric Surgeons (KAPS) in 2020. Methods: The clinical data of pediatric patients diagnosed with and treated for neuroblastoma from 2005 to 2019 in 19 hospitals of KAPS members were collected. Survival and prognostic factor analyses were performed using the log rank test and Cox proportional hazard analysis. A p-value <0.05 was considered significant. Results: A total of 669 patients with neuroblastoma were registered for the study. The results were presented and discussed at the 36th annual meeting of the KAPS, which was held in Seoul on August 21, 2020. Conclusion This study provides information on patient demographics, prognostic outcomes, and comprehensive treatment outcomes for neuroblastoma. The study is expected to be an important reference for improving pediatric surgeons’ understanding and treatment of neuroblastoma.

Purpose: To report the findings of a perception survey on intestinal malrotation conducted by the Korean Association of Pediatric Surgeons (KAPS) in 2021. Methods: The perceptions on intestinal malrotation regarding clinical decision making of the KAPS members were collected through web-based survey. Results: A total of 22 surgeons were answered for this study. The results were presented and discussed at the 37th annual meeting of KAPS, which was held in Seoul on June 18, 2021. Conclusion This study provides the clinical decisions of the KAPS members on the intestinal malrotation. The study is expected to be an important reference for improving pediatric surgeons’ understanding and treatment of intestinal malrotation.

Purpose: Biliary atresia (BA) is a rare but progressive cholangiopathy and the leading cause of pediatric liver transplantation worldwide. The Korean Association of Pediatric Surgeons (KAPS) has conducted three national surveys (2001, 2011, and 2023) to assess long-term trends in the diagnosis, treatment, and outcomes of BA. This study provides a comparative analysis of the 2nd and 3rd national surveys, with reference to selected findings from the 1st survey. Methods: This study included 453 patients from the 3rd national survey (2011–2021) and 435 patients from the 2nd survey (2001–2010), all of whom underwent Kasai portoenterostomy. Data were collected via electronic case report forms from pediatric surgical centers nationwide. Comparisons were made regarding demographics, clinical features, diagnostic patterns, operative details, follow-up outcomes, and survival. Kaplan–Meier analysis was used to evaluate long-term survival. Results: The mean number of BA patients per year remained stable between surveys (43.5 in the 2nd, 41.18 in the 3rd), though centralization of care increased, with 61.5% of cases managed by two major institutions in the 3rd survey. The median age at surgery decreased, and the use of preoperative imaging (especially magnetic resonance cholangiopancreatography) increased. The 10-year native liver survival rate declined from 59.8% to 53.7%, while overall 10-year survival improved slightly (92.9% to 93.2%). Postoperative complications, such as cholangitis and liver failure, persisted but were better categorized. The 3rd survey also reported improved mortality (4.9%) and reduced follow-up loss (11.5%) compared to the 2nd survey. Conclusion While overall survival after Kasai operation has remained high and even improved, native liver survival has slightly declined. The findings reflect earlier diagnosis, more consistent diagnostic imaging, and increasing centralization of care. These trends underscore the importance of long-term nationwide data collection in guiding future strategies for BA management in Korea.

Purpose: This study aims to investigate and compare the incidence, demographic characteristics, clinical manifestations, preoperative diagnostic methods, anatomical classifications, associated anomalies, operative treatments, and postoperative outcomes of patients with intestinal atresia treated by the members of the Korean Association of Pediatric Surgeons (KAPS) through three nationwide surveys. Methods: KAPS conducted 3 national surveys in 1998, 2010, and 2024 to examine the patients diagnosed with intestinal atresia. In preparation for the survey, we developed a customized case registration form to obtain data on patient sex, birth weight, gestational age, clinical manifestations, preoperative diagnostic methods, anatomical types, associated anomalies, operative treatments, and postoperative outcomes. Authorized KAPS members completed the case registration form. Results: The first, second, and third national surveys included 218, 222, and 236 individuals diagnosed with intestinal atresia, respectively. The male-to-female ratios were 1.5:1, 1.1:1, and 1.1:1, respectively. The first, second, and third national surveys revealed that 34.3%, 43.3%, and 53.4% of patients were born before 37 weeks of gestation, respectively. Additionally, 28.7%, 32.0%, and 40.7% of patients had a birth weight under 2,500 g. In the third national survey, duodenoduodenostomy was the most common procedure, performed in 70 out of 82 patients diagnosed with duodenal atresia. Resection and anastomosis were the main surgical procedures conducted in 47 out of 54 cases of jejunal atresia and 74 out of 92 cases of ileal atresia. The mortality rates in the first, second, and third national surveys were 13.8%, 3.6%, and 1.3% respectively, with the lowest rate observed in the third national survey. Conclusion These national surveys offer valuable insights into the current state of intestinal atresia, including specific surgical interventions and postoperative outcomes in South Korea. For pediatric surgeons aiming to enhance their understanding of intestinal atresia and its treatment options, these surveys could be an indispensable resource and guide.