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.Prevalence and Molecular Epidemiology of Extended-Spectrum β-Lactamase–Producing Escherichia coli and Effects of Antimicrobial Use in Multiple Pig Industry Sectors in Korea
Young Ah KIM ; Hyunsoo KIM ; Young Hee SEO ; Kyungwon LEE
Annals of Laboratory Medicine 2026;46(2):155-161
Background:
The spread of antimicrobial-resistant bacteria has close relationships among humans, animals, and the environment, necessitating the implementation of the “One Health” approach. In previous study, the prevalence and molecular epidemiology of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) were investigated across multiple pig industry sectors in Korea. In this study, animal developmental stages and antimicrobial usage policies on farms were also considered.
Methods:
A total of 6,288 non-duplicated samples were collected from pig farms, slaughterhouses, and their personnel from three provinces in Korea between 2020 and 2022.Antimicrobial susceptibility and ESBL gene characterization were performed on the samples.
Results:
Overall, 1,084 ESBL-EC isolates were collected, with positivity detection rates of 24.7%, 23.3%, 12.7%, 3.9%, 17.2% in pigs, workers, the environment, meat, and total samples, respectively. Common ESBL types were blaCTX-M-55 (N = 628), blaCTX-M-15 (N = 204), and blaCTX-M-14 (N = 127). Pig-derived E. coli isolates had antimicrobial resistance (AMR) rates of 80.4%, 47.2%, 32.6%, 36.7%, 43.4%, 62.4%, and 72.1% to ampicillin, piperacillin, cefazoline, ciprofloxacin, cotrimoxazole, chloramphenicol, and tetracycline, respectively.AMR rates were lower in the finishing stage pigs than in the lactating stage pigs and tended to decrease during animal development for most antimicrobials. AMR rates were higher in pig farms with a customary antimicrobial use policy than in those with a low-level antimicrobial use policy.
Conclusions
The findings highlight the significance of elucidating AMR networks among humans, animals, and the environment. Prudent antimicrobial usage and continuous AMR monitoring in the pig industry are crucial to safeguard food safety.
3.Comparison of Broad-Spectrum Antibiotic Use According to Hospice Utilization Among Patients with Cancer at the End of Life in South Korea: A Nationwide Analysis
Ye Sul JEUNG ; Hak Jun KIM ; Jiwon YU ; Jeong-Han KIM ; Jin-Ah SIM ; Shin Hye YOO
Journal of Hospice and Palliative Care 2026;29(2):41-50
Purpose:
We aimed to compare broad-spectrum antibiotic use between hospice and nonhospice patients with cancer at the end of life using nationwide data from Korea.
Methods:
In this retrospective cohort study, we analyzed the Korean National Health Insurance Service data of adult patients with cancer who died between 2018 and 2021. Hospice users were defined as patients who received inpatient, home-based, or consultation-based hospice care before death. We applied propensity score matching (1:2) to balance the baseline characteristics of the hospice and non-hospice groups. Broad-spectrum antibiotic use, including anti-pseudomonal penicillins, anti-pseudomonal cephalosporins, carbapenems, and glycopeptides, was assessed during the last 3 months of life using prescription proportions and days of therapy per 1,000 patient-days.
Results:
After matching, 38,102 hospice and 75,736 non-hospice users were analyzed. During the last 3 months of life, 74.6% of hospiceand 79.0% of non-hospice users received at least one broad-spectrum antibiotic (P<0.001).The proportion of patients receiving broad-spectrum antibiotics was generally lower amonghospice users across all time intervals (P<0.001), and the number of days of therapy wasalso lower, with the largest differences observed during the final week and last 3 days of life.Subgroup analyses showed the highest antibiotic exposure among patients with hematologic and pancreatobiliary cancers, particularly in the non-hospice group.
Conclusion
Hospice involvement was associated with lower use and reduced exposure to broad-spectrum antibiotics among patients with cancer near the end of life. These findings support the alignment of end-of-life treatment decisions with the comfort-oriented goals of hospice care.
4.Association between lifestyle values, lifestyle, and quality of life among the community-dwelling late middle-aged and older adults: A retrospective cross-sectional analysis
Suyeong BAE ; Ickpyo HONG ; Ah-Ram KIM
Journal of Korean Gerontological Nursing 2026;28(1):17-25
This study aims to investigate the association of lifestyle values with lifestyle and quality of life among community-dwelling late middle-aged and older adults. Methods: This retrospective cross-sectional study analyzed secondary data of 200 late middle-aged and older adults. Lifestyle and lifestyle values were measured by Yonsei Lifestyle Profile (YLP) and YLP-Value, respectively. The mediator was quality of life, and a mediation analysis was conducted to examine the relationship between lifestyle values, lifestyle, and quality of life. Our study then repeated the analysis by dividing lifestyle into three components: physical activity, nutrition/eating habit, and activity participation. Results: Mediation analysis revealed significant associations across all pathways (all p<.001). The lifestyle values were associated with lifestyle (β=.40). Both lifestyle value (β=.40) and lifestyle (β=.18) were positively associated with quality of life. The indirect effect of lifestyle values on quality of life, mediated by lifestyle, accounted for 14.58% of the total effect, with the direct effect constituting 85.42%. Conclusion: Among the three components of lifestyle, a mediation effect was observed between lifestyle values, nutrition/eating habit, and quality of life. Our results indicate the need for education to increase lifestyle values within lifestyle programs, emphasizing the significance of lifestyle values in enhancing both lifestyle and quality of life among late middle-aged and older adults. Health professionals may integrate the results into interventions by recognizing the importance of lifestyle values.
5.Evidence appraisal and updates for the 2025 Dietary Reference Intakes for Koreans for calcium
Seul Ki CHOI ; Seong-Ah KIM ; Clara Yongjoo PARK ; Kirang KIM
Journal of Nutrition and Health 2026;59(2):176-191
Purpose:
The Dietary Reference Intakes for Koreans (KDRIs) serve as a foundation for nutrition policy, nutrition education, and dietary intake evaluation among healthy Koreans.The KDRIs are revised every five years to ensure that the guidelines are based on a robust and up-to-date scientific foundation. For the 2025 KDRIs for calcium, the 2020 KDRIs were revisited, and references were critically evaluated.
Methods:
All references cited in the 2020 KDRIs were extracted, reviewed, and organized according to the framework for the estimated average requirement (EAR). Each reference was evaluated based on the participant characteristics, including age, race/ethnicity, and health status, as well as study design, exposure, and outcomes. In addition, calculations for the EAR and Recommended Nutritient Intakes were re-examined for each sex and age group and compared with the current literature.
Results:
Major revisions in the 2025 KDRIs were driven by updates in the reference bodyweight, improved consistency in rounding and coefficients of variation, inclusion of studies in East Asian populations, and clarification of the use of calcium balance studies.Nevertheless, further studies in Koreans, particularly in pregnant and lactating women, are needed to strengthen the scientific evidence for the calcium DRI.
Conclusion
The 2025 KDRIs for calcium were revised to be based on more robust logical reasoning and calculation methods. Future research conducted on Korean populations is necessary to define the calcium requirements for Koreans more accurately.
6.Vitamin B12 intake and dietary sources across the life cycle in Koreans:Korea National Health and Nutrition Examination Survey 2022–2024
Yeon Joo LEE ; Hyun Ju KIM ; Seon Ah SIM
Journal of Nutrition and Health 2026;59(2):202-217
Purpose:
This study aimed to evaluate age- and sex-specific dietary vitamin B12 intake among Koreans, assess adequacy relative to the 2025 Korean Dietary Reference Intakes, and identify major food groups using nationally representative data from the 2022–2024 Korea National Health and Nutrition Examination Survey (KNHANES).
Methods:
Data from 19,191 participants in the KNHANES 2022–2024 aged1 year and older were analyzed after excluding individuals with extreme energy intake values. Individual vitamin B12 intake was calculated based on 24-hour dietary recall data using the Korean National Standard Food Composition Database (version 10.3). Intake levels were evaluated against age- and sex-specific Estimated Average Requirement (EAR) and Recommended Nutrient Intake (RNI) values. Complex sample general linear models and cross-tabulation analyses were conducted to examine differences in intake and adequacy.
Results:
The mean vitamin B12 intake of the study population was 8.27 μg/day, exceeding the RNI in most age groups. The proportion of individuals meeting or exceeding the RNI was generally high; however, the prevalence of intake below the EAR increased with age, particularly among older women, approximately 35% of whom were at risk of inadequate intake. Animal-based foods, including fish and shellfish, meat, eggs, and dairy products, were the primary contributors to vitamin B12 intake. Adults and older adults with intake below the RNI consumed significantly lower amounts of these food groups compared with those meeting the RNI.
Conclusion
Although overall vitamin B12 intake among Koreans appears sufficient, older adults remain at increased risk of insufficient intake. Continuous monitoring of vitamin B12 nutritional status and targeted dietary strategies, with a focus on older populations, is warranted to prevent potential deficiencies.
8.Myopia Management Consensus Statement in South Korean Children 2025 by the Korean Myopia Society for the Korean Association for Pediatric Ophthalmology and Strabismus
Yeon-Hee LEE ; Jae Yun SUNG ; Sun Young SHIN ; Young-Woo SUH ; Ungsoo Samuel KIM ; Hyunkyung KIM ; Kyung-Ah PARK ; Su Jin KIM ; MiRae KIM ; Hyun Jin SHIN ; Kyeong Wook LEE ; Haeng-Jin LEE ; So Young HAN ; Jinu HAN ; Eun Hee HONG ; Seung-Hee Hannah BAEK ; Hae Jung PAIK ;
Korean Journal of Ophthalmology 2026;40(2):185-205
Myopia, particularly high myopia, is a significant risk factor for several ocular pathologies including cataract, glaucoma, and retinal detachment. Excessive axial elongation associated with high myopia can induce biomechanical stretching, increasing the risk of serious complications like posterior staphyloma and myopic maculopathy. Global meta-analyses estimate that approximately 10 million people were visually impaired due to myopic maculopathy in 2015, with 3 million being blind. Recent nationwide surveys in South Korea revealed a prevalence of 65.4% for myopia and 6.9% for high myopia in children and adolescents, highlighting the urgent need for effective management. Delaying the onset and slowing the progression of myopia during childhood and adolescence is crucial for reducing the potential lifetime risk of these complications. This consensus statement, prepared by the Korean Myopia Society for the Korean Association for Pediatric Ophthalmology and Strabismus (KAPOS), reviews the current evidence for myopia control interventions and provides management strategies applicable to the South Korean clinical setting. Key interventions covered include lifestyle modifications (outdoor time, near work adjustment), optical methods (myopia-control spectacle lenses, dual-focus soft contact lenses, orthokeratology), and pharmacologic treatment (low-concentration atropine), as well as combination therapies. The statement also addresses patient selection, treatment outcome evaluation using spherical equivalent and axial length changes, and the crucial aspects related to treatment cessation and the rebound effect.
10.Deep Learning–Based Bone Age Assessment for Predicting Final Adult Height in Girls With Central Precocious Puberty
Jeong Min SONG ; Pyeong Hwa KIM ; Young Ah CHO ; Ah Young JUNG ; Jin Seong LEE ; Ja Hye KIM ; Hee Mang YOON
Korean Journal of Radiology 2026;27(6):568-577
Objective:
This study aimed to evaluate the accuracy of predicting final adult height (FAH) in Korean girls with central precocious puberty (CPP) using artificial intelligence (AI)-derived bone age assessments integrated into the Bayley–Pinneau (BP) or Korean National Growth Chart (KGC) prediction models.
Materials and Methods:
This single-center, retrospective study included 122 Korean girls with CPP who received gonadotropinreleasing hormone agonist (GnRHa) treatment for at least two years between January 2000 and November 2022. We assessed bone age and predicted adult height at the initiation and completion of GnRHa treatment. We used three bone age assessment methods: human expert assessment based on the Greulich-Pyle (GP) atlas (Human-GP), AI-derived GP (AI-GP), and AI-weighted GP scoring (AI-GPw). We calculated predicted adult heights (PAHs) using both the BP and KGC models, generating 12 PAH estimates per patient (2 time points x 3 bone-age methods x 2 height-prediction models). We assessed prediction accuracy and agreement with FAH using linear regression analysis and Bland–Altman plots and performed multivariable analysis to identify significant predictors of FAH.
Results:
Human-GP, AI-GP, and AI-GPw demonstrated comparable overall performance in predicting FAH (R 2 : 0.470–0.646 and 0.691–0.822 for treatment initiation and completion, respectively). AI-GPw combined with BP yielded slightly better point estimates but showed no statistically significant differences. At both time points, the BP model demonstrated consistently narrower 95% limits of agreement (LoA) than the KGC model. Multivariable analysis identified AI-GPw-BP and height percentile score as significant predictors of FAH at both time points; mid-parental height was significant only at treatment initiation.
Conclusion
Human-GP, AI-GP, and AI-GPw demonstrated comparable accuracy in predicting FAH. The BP model demonstrated consistently narrower 95% LoA than did the KGC model. AI-GPw-BP was an independent predictor of FAH. These findings support the clinical utility of AI-derived bone age assessments for individualized FAH prediction in patients with CPP.

Result Analysis
Print
Save
E-mail