1.Molecular Epidemiology of Extended-spectrum β-Lactamase-producing Escherichia coli in South Korea: A Korean Global Antimicrobial Resistance Surveillance System Report
Dokyun KIM ; SungYoung LEE ; Jun Sung HONG ; Min Hyuk CHOI ; Hyun Soo KIM ; Young Ree KIM ; Young Ah KIM ; Young UH ; Kyeong Seob SHIN ; Jeong Hwan SHIN ; Jeong Su PARK ; Kyoung Un PARK ; Soo Hyun KIM ; Jong Hee SHIN ; Jungsik YU ; Seok Hoon JEONG
Annals of Laboratory Medicine 2026;46(1):72-82
Background:
Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli is among the most important multidrug-resistant pathogens causing bloodstream infections (BSIs).Cefotaximase (CTX-M) enzymes are the most common and highly diverse ESBL family in E.coli. CTX-M-15 in group CTX-M-1 and CTX-M-14 in group CTX-M-9 are the most extensively disseminated enzymes. Multidrug-resistant E. coli strains complicate empirical therapy and increase healthcare burden globally and in Korea. We investigated the molecular epidemiology, sequence types (STs), and ESBL genotypes of E. coli bloodstream isolates in Korea and identified clinical risk factors for cefotaxime resistance.
Methods:
We collected all non-duplicated isolates of E. coli and related clinical information from patients with BSIs at eight sentinel hospitals in the Korean Global Antimicrobial Resistance Surveillance System (Kor-GLASS) collection network during 2017–2021. Duplicate isolates were removed to ensure representativeness of the data. Antimicrobial susceptibility was tested using disk diffusion tests, and multilocus sequence typing and betalactamase genotyping were performed.
Results:
Among 9,232 E. coli blood isolates, resistance rates to cefotaxime and ceftazidime were 36.4% and 11.4%, respectively. Among the clinical factors, age > 65 yrs (adjusted odds ratio [aOR], 1.36), hospital-origin infection (aOR, 2.55), and admission type (intensive care unit [ICU] vs. general ward; aOR, 1.34) were significant cefotaxime resistance risk factors. ST131 was the most prevalent among cefotaxime-resistant E. coli (64.8%, 2,180/3,363), followed by ST1193 (5.3%, N = 177), and ST69 (5.1%, N = 170).ST131, ST648, ST405, and ST410 cefotaxime-resistant E. coli isolates frequently harbored blaCTX-M-15, whereas ST1193 and ST68 showed a high proportion of blaCTX-M-27 carriers, and most ST457 and ST5150 isolates carried blaCTX-M-55.
Conclusions
Continuous monitoring of ESBL-producing E. coli is required to prevent further dissemination, guide empirical therapy, inform infection control policies, and ensure early detection of multidrug-resistant clones with the potential for widespread transmission.
2.Loss of Inspiratory Augmentation as a Predictive Factor for the Development of Gastroesophageal Reflux Disease After Peroral Endoscopic Myotomy in Patients With Achalasia
Min-Jae KIM ; Se Yeon JEON ; Jun Chul PARK ; Young Hoon YOUN ; Hyojin PARK
Journal of Neurogastroenterology and Motility 2026;32(1):129-135
Background/Aims:
Gastroesophageal reflux disease (GERD) after peroral endoscopic myotomy (POEM) is a significant challenge. Disruption of the lower esophageal sphincter during POEM and dysfunction of the crural diaphragm, which contributes to esophagogastric junction pressure, may lead to GERD after POEM. We aim to identify predictors of GERD after POEM and focus on physiological parameters of esophagogastric junction pressure in patients with achalasia before POEM.
Methods:
We retrospectively analyzed a prospectively collected database of patients who underwent POEM between July 2016 and August 2023. Ninety-two patients with achalasia who underwent high-resolution manometry and endoscopy before and after POEM were included.
Results:
Forty-nine (53.3%) patients were diagnosed with GERD. Patient demographics, achalasia subtypes, prior treatments, myotomy length, and myotomy orientation were not associated with GERD after POEM. Loss of inspiratory augmentation before POEM was associated with GERD after POEM (P < 0.05). GERD occurred more frequently in patients with a shorter intra-abdominal lower esophageal sphincter length before POEM. Type III esophagogastric junction morphology in the GERD group (37.1%) was more common than that in the non-GERD group (15.8%). Loss of inspiratory augmentation occurred more frequently in patients with type III esophagogastric junction pressure morphology.
Conclusion
Loss of inspiratory augmentation may predict GERD after POEM.
3.Anticancer Treatment Influences TREM2 in Tumor-Associated Macrophages in Lung Cancer
Yoon Jin CHA ; Eun Hye LEE ; Chi Young KIM ; Yong Jun CHOI ; Min Kyung PARK ; Sang Hoon LEE ; Eun Young KIM ; Yoon Soo CHANG
Cancer Research and Treatment 2026;58(2):465-480
Purpose:
The triggering receptor expressed on myeloid cells 2 (TREM2) creates an immunosuppressive environment, but the effects of anticancer treatment on TREM2 and the tumor microenvironment (TME) are not well established. This study investigates the impact of chemotherapy on TREM2-expressing macrophages within the lung adenocarcinoma TME.
Materials and Methods:
Using single-cell RNA sequencing datasets of paired normal-appearing lung tissue (NL) and tumor (Tu), human and mouse lung cancer tissue, and THP-1 cells, we observed the effects of anticancer drugs on them.
Results:
Myeloid cells (MY) were the second-most abundant non-epithelial component in the Tu, though less prevalent than in NL. Specific MY subclusters abundant in Tu showed overexpression of TREM2. In lung cancer-induced Kras-G12D mice, M2 proportion increased in Tu compared to NL; cisplatin increased TREM2+ M2 proportion in Tu. TREM2+ cells in Tu showed interactions with cell clusters showing characteristics of interstitial macrophage such as mo-lineage, mono-Mc, and CD163/LGMN cells via FN:CD44 and MIF:CD74+CXCR4, suggesting that they influence the recruitment of those cells to Tu and TME reshape. In M0-state THP-1 cells, cisplatin and osimertinib treatments induced polarization towards M1 and M2 states and increased TREM2 expression. Cisplatin promoted uptake of phosphatidylserine-coated latex beads by M0 cells, whereas osimertinib reduced uptake by polarized macrophages. These findings suggest anticancer treatments impact the lung immune microenvironment by altering the TREM2+ cells.
Conclusion
Given TREM2’s central inhibitory role in the tumor immune environment, effects of chemotherapeutic agents should be considered in developing TREM2-targeting therapies.
4.Detection Ability of Quality of Life Changes and Responsiveness of the KOQUSS-40 and the EORTC QLQ-C30/STO22 in Patients Who Underwent Gastrectomy: A Prospective Comparative Study
Bang Wool EOM ; Keun Won RYU ; Ji Yeong AN ; Yun-Suhk SUH ; In CHO ; Sung Geun KIM ; Ji-Ho PARK ; Hoon HUR ; Hyung-Ho KIM ; Sang-Hoon AHN ; Sun-Hwi HWANG ; Hong Man YOON ; Ki Bum PARK ; Hyoung-Il KIM ; In-Gyu KWON ; Han-Kwang YANG ; Byoung-Jo SUH ; Sang-Ho JEONG ; Tae-Han KIM ; Oh Kyoung KWON ; Hye-Seong AHN ; Ji Yeon PARK ; Ki Young YOON ; Myoung Won SON ; Seong-Ho KONG ; Young-Gil SON ; Geum Jong SONG ; Jong Hyuk YUN ; Jung-Min BAE ; Do Joong PARK ; Sol LEE ; Jun-Young YANG ; Kyung Won SEO ; You-Jin JANG ; So Hyun KANG ; Joongyub LEE ; Hyuk-Joon LEE ;
Cancer Research and Treatment 2026;58(1):221-231
Purpose:
The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ).
Materials and Methods:
A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire.
Results:
Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ.
Conclusion
KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.
5.Survival Rates of Patients with Gastric Cancer According to Age and Sex: A Large-Scale Study Using Data from 14,739 Patients
Yonghoon CHOI ; Nayoung KIM ; Ji Hyun KIM ; Hyeong Ho JO ; Hyeon Jeong OH ; Hye Seung LEE ; Yu Kyung JUN ; Hyuk YOON ; Cheol Min SHIN ; Young Soo PARK ; Dong Ho LEE ; So Hyun KANG ; Young Suk PARK ; Sang-Hoon AHN ; Yun-Suhk SUH ; Do Joong PARK ; Hyung Ho KIM ; Ji-Won KIM ; Jin Won KIM ; Keun-Wook LEE ; Won CHANG ; Yoon Jin LEE ; Kyoung Ho LEE ; Young Hoon KIM
Cancer Research and Treatment 2026;58(1):252-263
Purpose:
The male predominance in the incidence of gastric cancer (GC) is established; however, sex differences in the prognosis of GC remain controversial. As such, this study analyzed the prognosis of patients with GC based on age and sex.
Materials and Methods:
Data from 14,739 patients diagnosed with GC at Seoul National University Bundang Hospital between 2003 and 2023 were analyzed. Baseline characteristics, histological types of GC, overall and GC-specific survival rates (age and stage stratification), and associated risk factors were analyzed.
Results:
Females were significantly younger (p < 0.001) and exhibited more gastric body cancers (p < 0.001) and tumors with diffuse-type or poorly differentiated histology (p < 0.001) than males. Females exhibited an advantage over males in terms of overall survival (p=0.004), but not in GC-specific survival. However, age stratification revealed significant sex differences, that females < 50 years of age exhibited survival disadvantages (p < 0.001); however, this trend was reversed with age, and females > 60 years exhibited survival advantages (p < 0.001) for both overall and GC-specific survival. This may be explained by the lower ratio of diffuse-type GC as females age. Furthermore, in the analysis according to stage, females with stage IV disease exhibited significant survival disadvantages, with significantly younger age and a higher proportion of diffuse-type GC which exhibits aggressive features, resulting in poorer survival than in males.
Conclusion
Age and stage stratification revealed significant differences in survival between the sexes, which can be helpful for public health strategies.
6.Exploring Oncologists’ Perspectives on the Early Integration of Specialty Palliative Care in Korea: Challenges, Needs, and Clinical Implications
Shin Hye YOO ; Yu Jung KIM ; Ye Sul JEUNG ; Jung Sun KIM ; Kwonoh PARK ; Eun Mi NAM ; Si Won LEE ; Jun Ho JI ; Jwa Hoon KIM ; Joon Young HUR ; Song Ee PARK ; Jung Lim LEE ; Su-Jin KOH
Cancer Research and Treatment 2026;58(1):339-348
Purpose:
This study aimed to explore the practices, perceptions, and barriers related to specialty palliative care (SPC) referrals among oncologists in Korea, highlighting the clinical implications of early integration.
Materials and Methods:
A cross-sectional online survey targeting board-certified hemato-oncology specialists was conducted between August 1-25, 2024. The survey assessed referral practices, attitudes toward early SPC integration, referral criteria, barriers, and institutional characteristics.
Results:
A total of 227 oncologists participated (response rate, 36.7%). Among them, 68.7% reported frequent SPC referrals, with higher referral rates observed among younger physicians, those in tertiary hospitals, and institutions with in-house SPC teams (p < 0.001). Although 74.9% supported early SPC integration, referrals were often inconsistently timed, frequently occurring after disease progression or at the discontinuation of chemotherapy. For time-based referrals, the most commonly endorsed triggers were disease progression despite palliative second-line treatment and a prognosis of expected mortality within 6-12 months. Need-based referral triggers such as patient or family requests (96.5%), psychological distress (89.9%), or uncontrolled symptoms (83.3%), were also widely endorsed. The major barriers to early SPC integration included patient and family resistance (70.0%) and limited availability of SPC teams (34.4%).
Conclusion
This study emphasizes the importance of systematic efforts to promote timely SPC integration in Korea, including education to raise patient awareness, improved referral systems, and enhanced infrastructure. The positive attitudes toward early SPC among oncologists reflect a growing recognition of its value, highlighting the need for strategies that align with international standards.
7.Guidelines for the Management of Adult Subglottic and Tracheal Stenosis From the Korean Bronchoesophagological Society
Jung-Hae CHO ; Gene HUH ; Jae-Keun CHO ; Jae Won CHANG ; Jun-Ook PARK ; Young Chan LEE ; Jae Hyun JEON ; Jeon Yeob JANG ; Byeong-Ho JEONG ; Yeon Soo KIM ; Inn-Chul NAM ; Gil Joon LEE ; Woo Sik YU ; Heejin KIM ; Minhyung LEE ; Ji Won KIM ; Seung Hoon WOO ; Il-Seok PARK ; Jin Pyeong KIM ;
Clinical and Experimental Otorhinolaryngology 2026;19(1):1-20
Subglottic stenosis (SGS) and tracheal stenosis (TS) are rare conditions that can cause significant breathing difficulties and, if not properly managed, may lead to life-threatening complications. Despite their clinical importance, debate continues regarding the optimal management of adult SGS and TS, and no comprehensive guidelines have been established to date. The Korean Bronchoesophagological Society appointed a task force to develop clinical practice guidelines with the goal of providing evidence-based recommendations for managing SGS and TS in adults. The task force conducted a systematic review of the relevant literature by searching PubMed, Embase, and the Cochrane Library using predefined search terms aligned with key clinical questions. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach, which also informed the formulation and reporting of the recommendations. The strength of each recommendation reflects the guideline panel’s confidence that the benefits of an intervention outweigh its risks for eligible patients. After drafting the guidelines, feedback was obtained through Delphi questionnaires completed by members of the Korean Bronchoesophagological Society. Ultimately, the committee developed 17 evidence-based recommendations across four categories: initial evaluation, medical management, surgical treatment, and postoperative management and rehabilitation. These guidelines aim to support clinicians in delivering optimal care to adult patients with SGS and TS.
8.Risk of cardiovascular disease associated with use of tumor necrosis factor inhibitors in ankylosing spondylitis
Ji-Won KIM ; Jun Sik YOON ; Sojeong PARK ; Hasung KIM ; Bo Young KIM ; Hwajeong LEE ; Sung-Hoon PARK ; Seong-Kyu KIM ; Jung-Yoon CHOE
Journal of Rheumatic Diseases 2026;33(1):46-54
Objective:
To examine the risk of cardiovascular disease (CVD) associated with use of tumor necrosis factor inhibitors (TNFi) in patients with ankylosing spondylitis (AS).
Methods:
This study used data from the Korean National Health Insurance database. Patients aged ≥18 years who were newly diagnosed with AS between 2010 and 2018 and did not suffer prior CVD were included. The primary outcome was a composite endpoint of myocardial infarction (MI) or stroke. The secondary outcomes were specific endpoints of MI, stroke, or congestive heart failure. TNFi use was evaluated as a time-dependent variable. Cox proportional hazard regression was used to examine the association between TNFi use and risk of incident CVD.
Results:
Of 19,775 patients (mean age, 36.1 years; 75% male), 5,978 (30.2%) were exposed to TNFi treatment during the study period. During a follow-up of 4.8 (interquartile range, 2.9~7.2) years, 522 events of MI or stroke occurred. TNFi use was associated with a lower risk of MI or stroke than no TNFi use after adjusting for traditional CV risk factors and medications (adjusted hazard ratio [aHR], 0.72; 95% confidence interval [CI], 0.55~0.94). The lower risk of MI or stroke associated with TNFi use was consistently observed across subgroups. Risk of congestive heart failure did not differ between users and non-users of TNFi (aHR, 0.94; 95% CI, 0.75~1.18).
Conclusion
In a real-world AS cohort, TNFi treatment was associated with a reduced risk of atherosclerotic CVD. However, TNFi use was not associated with risk of congestive heart failure.
9.Macro-Aspartate Aminotransferase Elevation in a Patient with Chronic Hepatitis B
Nae-Yun HEO ; Jae-Hoon KIM ; Seungha PARK ; Joon Hyuk CHOI ; Tae Oh KIM ; Jin LEE ; Yong Eun PARK ; Kyung Ran JUN
The Korean Journal of Gastroenterology 2026;86(2):122-127
Although aspartate aminotransferase (AST) is a serum marker of hepatocellular damage in chronic hepatitis, it is difficult to interpret very high AST levels with concurrent low alanine aminotransferase (ALT) levels. Macro-AST is an immunoglobulin-AST complex that can present as aberrant high enzymatic activity without significant inflammation in the liver. Two patients with chronic hepatitis B presented with disproportionate AST elevations. Their plasma samples were precipitated with polyethylene glycol (PEG) and stored at 4°C for macro-AST determinations. In Case 1, PEG precipitation showed 100% removal of AST activity, and refrigerated storage resulted in a ~70% decline over seven days, confirming macro-AST. In Case 2, both tests showed minimal changes, suggesting that macro-AST was unlikely. The AST levels normalized after antiviral therapy, suggesting immune-active hepatitis as the probable cause, but the other contributing factors could not be completely excluded. The abrupt decrease in AST activity after PEG precipitation and during refrigeration storage suggests that relatively high AST values compared to ALT might be attributed to the presence of macro-AST.These non-invasive methods for detecting macroenzymes might help the patient avoid unnecessary further work-ups.
10.Association of Aerobic Physical Activity and Resistance Exercise with Glycated Hemoglobin in Women with Diabetes
Susanna JUN ; Ji Won KANG ; Dong-Hyuk PARK ; Ki-Yong AN ; Dong Hoon LEE ; Minsuk OH ; Justin Y. JEON
Yonsei Medical Journal 2026;67(1):71-78
Purpose:
The American Diabetes Association recommends that patients with diabetes engage in at least 150 minutes of physical activity (PA) per week and perform resistance exercise (RE) at least twice weekly. However, their benefits in controlling glucose levels among women with diabetes are not completely understood. Therefore, we investigated whether meeting PA or RE guidelines is associated with lower odds of uncontrolled glycated hemoglobin (HbA1c) among women.
Materials and Methods:
We analyzed 1213 women with diabetes from the Korea National Health and Nutrition Examination Survey 2014–2018. Using PA questionnaires, participants were categorized according to whether they met aerobic PA guidelines (≥150 minutes of moderate-to-vigorous PA), RE guidelines (≥twice weekly), or both. Further, HbA1c levels >7.5% were classified as uncontrolled glycemic levels. Multivariate logistic regression models were employed to investigate whether meeting PA or RE guidelines is associated with uncontrolled HbA1c.
Results:
There was no association between meeting aerobic PA guidelines of >150 minutes per week and uncontrolled HbA1c.However, participating in RE > twice weekly was associated with a 49% lower odds of HbA1c >7.5% in fully adjusted models (odds ratio: 0.51; 95% confidence interval: 0.30–0.87; p<0.05). Moreover, the association between RE participation and lower odds of HbA1c >7.5% was observed regardless of age, body mass index, and prevalence of hypertension.
Conclusion
Participation in RE may be important for women with diabetes for glycemic control. Further research is needed to better understand the associations between HbA1c and different exercise modalities (i.e., resistance vs. aerobic exercise) in women with diabetes.

Result Analysis
Print
Save
E-mail