1.Diagnostic Accuracy of Serological Tests for Mycoplasma pneumoniae Infections in Children with Pneumonia, Based on Symptom Onset
Gahee KIM ; Ki Wook YUN ; Dayun KANG ; Taek Jin LEE ; Byung Wook EUN ; Hyunju LEE ; Yae-Jean KIM ; Doo Ri KIM ; Areum SHIN ; Hyun Mi KANG ; Ye Ji KIM ; Byung Ok KWAK ; Younghee LEE ; Ye Kyung KIM ; Young June CHOE ; Woosuck SUH ; Kyo Jin JO ; Kyung-Ran KIM ; Eun Young CHO ; Kyung Min KIM ; Joon Kee LEE ; Su Eun PARK
Annals of Laboratory Medicine 2026;46(2):162-170
Background:
Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in children, with a rising incidence of macrolide resistance. Early diagnosis is crucial for reducing the disease burden; however, current diagnostic tools have limitations.We evaluated the diagnostic accuracy of serological assays and their performance based on symptom onset in children with CAP.
Methods:
From September 2023 to September 2024, we prospectively enrolled children with CAP, classified as M. pneumoniae pneumonia (MPP) or non-MPP, from 16 hospitals in Korea. Serological testing included chemiluminescence immunoassay (CLIA) and ELISA for detecting IgM and IgG, along with particle agglutination (PA) for total antibody measurements. Serological responses were analyzed at different times after symptom onset (0–4, 5–9, and 10–21 days).
Results:
Among 472 children with CAP (362 MPP, 110 non-MPP), 138 (29.2%) underwent PA testing, and 334 (70.8%) underwent IgM testing. PA at a 1:640 cutoff showed 48.0% sensitivity and 100% specificity. CLIA and ELISA showed comparable sensitivities (69.1% vs. 69.2%) and specificities (76.9% vs. 66.7%) for IgM testing. Seropositivity increased significantly with time since symptom onset (P for trend < 0.001), reaching 97.9% for IgM, 62.5% for IgG, and 94.7% for PA at 10–21 days.
Conclusions
The time post-symptom onset significantly influenced the diagnostic utility of serological tests for pediatric MPP, which showed limited value during the early stage of illness. These findings emphasize the importance of symptom onset-based interpretation of serological test results and their utility in complementing PCR when optimizing MPP diagnosis in children.
2.Nationwide Survey on Endoscopic Submucosal Dissection for Early Gastric Cancer in Korea: Results From the Korean College of Helicobacter and Upper Gastrointestinal Research (KCHUGR) 2023 Survey
Jae Yong PARK ; Jeong Hoon LEE ; Tae-Se KIM ; Da Hyun JUNG ; Bong Eun LEE ; Yonghoon CHOI ; Wan-Sik LEE ; Young-Il KIM ; Sun Hyung KANG ; Hyunsoo CHUNG ; Su Jin KIM ; Joon Sung KIM ; Donghoon KANG ; Su Youn NAM ; Seung Han KIM ; Hyo-Joon YANG ; Hyun LIM ; Jin LEE ; Seon-Young PARK ; Seung-Woo LEE ; Sun Moon KIM ; Sam Ryong JEE ; Dae Young CHEUNG ; Chung Hyun TAE ; Seokin KANG ; Sung Chul PARK ; Seung In SEO ; Cheol Min SHIN ; Kee Don CHOI ; Jong Yeul LEE ;
Journal of Gastric Cancer 2026;26(2):169-183
Purpose:
Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research.
Materials and Methods:
Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes.
Results:
Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days.
Conclusions
This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.
3.Eradication of Aspiculuris tetraptera in various immunodeficient mouse models using ivermectin: a case report
Ji-Hun LEE ; Eun-Seon YOO ; Na-Won KIM ; Han-Bi JEONG ; Ah-Reum KANG ; Sun-Min SEO ; Young-Jun PARK ; Byeong-Cheol KANG ; Yang-Kyu CHOI
Laboratory Animal Research 2026;42(1):82-87
Background:
Despite advancements in laboratory animal facility management, pinworm infections remain a persistent issue in immunodeficient mouse colonies. Rapid diagnosis and treatment are crucial to mitigating potential scientific and economic consequences. Effective control requires both the administration of anthelmintic agents and rigorous environmental decontamination. However, the safety and efficacy of these treatments in genetically modified mouse models remains uncertain.Case presentation Aspiculuris tetraptera infestation was identified in multiple immunodeficient mouse models housed in a laboratory facility. Diagnosis was confirmed through fecal flotation for egg detection and necropsy for adult worm examination in the large intestines. Mice received three subcutaneous ivermectin injections at two-week intervals, coupled with environmental decontamination using ivermectin spray for four consecutive weeks. Following treatment, all colonies tested negative for A. tetraptera without any mortality.
Conclusions
A combination of subcutaneous ivermectin injection and environmental spray application effectively eradicated A. tetraptera infestation in immunodeficient mouse colonies. The treatment protocol led to the complete elimination of eggs and adult worms, offering a practical strategy for managing pinworm infections in genetically modified mouse models. Limitations include the small sample size, and the lack of a comprehensive evaluation of physiological and metabolic safety in immunodeficient mice. Further validation will be required to confirm the broader applicability of this approach.
4.Vitamin/mineral and non-vitamin/ non-mineral supplement use of breast cancer survivors in Korea
Jioh KANG ; Jiyoung YOUN ; Hyun Jeong CHO ; Hyeong-Gon MOON ; Dong-Young NOH ; So-Youn JUNG ; Eun Sook LEE ; Zisun KIM ; Hyun Jo YOUN ; Jihyoung CHO ; Young Bum YOO ; Se Kyung LEE ; Jeong Eon LEE ; Seok Jin NAM ; Jun Won MIN ; Yoo Seok KIM ; Jihyoun LEE ; Seho PARK ; Joon JEONG ; Jung Eun LEE
Nutrition Research and Practice 2026;20(2):333-345
BACKGROUND/OBJECTIVES:
Dietary supplement use is common among breast cancer survivors, but studies on Asian populations remain limited. This study investigated dietary supplement use among Korean breast cancer survivors, distinguishing between vitamin/ mineral (VM) and non-vitaminon-mineral (NVNM) supplements.
SUBJECTS/METHODS:
This cross-sectional study included 1,136 stage I–III breast cancer survivors from 12 Korean hospitals, who survived more than 6 mon post-surgery. The participants completed a questionnaire on post-diagnostic dietary supplement use. Stepwise logistic regression was applied, calculating odds ratios (ORs) and 95% confidence intervals (CIs) to identify the demographic and clinical factors associated with VM and NVNM use.
RESULTS:
Seventy percent of survivors reported supplement use, with 25% using a single product. The most common VM supplements were multivitamins/minerals, vitamin D, and vitamin C, while the most common NVNM supplements included omega-3 fatty acids, probiotics, and ginseng. Survivors with higher education and greater physical activity were more likely to use VM supplements (ORs [95% CIs], 2.74 [1.76–4.25] for college graduates or above vs. middle school or below; 1.38 [1.02–1.88] for the most active group vs. the least active group). NVNM use was associated with higher education, greater physical activity levels, and a history of smoking (ORs [95% CIs], 2.29 [1.46–3.58] for college graduates or above vs. middle school or below; 1.52 [1.13–2.06] for the most active group vs. the least active group; 2.00 [1.23–3.25] for ever smokers vs. never smokers). Survivors who had undergone chemotherapy were also more likely to use NVNM supplements than those who had not (OR [95% CI], 1.37 [1.02–1.84]).
CONCLUSION
Seventy percent of Korean breast cancer survivors used dietary supplements in this study. VM use was associated with higher education and physical activity, while higher NVNM use was associated with higher education, greater physical activity, a history of smoking, and chemotherapy.
5.Discrepancy between Genetically Predicted and Observed Alcohol Intake and Its Impact on Gastric Cancer Susceptibility
Ga-Eun YIE ; Cheol Min SHIN ; Kyungtaek PARK ; Jinyeon JO ; Ah Ra DO ; Sungkyoung CHOI ; Jung Hun OHN ; Sejoon LEE ; Jeongseon KIM ; Sun Ha JEE ; Seung Joo KANG ; Nayoung KIM ; Sungho WON
Cancer Research and Treatment 2026;58(2):563-572
Purpose:
We aimed to investigate how genetic predisposition to drinking and gastric cancer (GC) modifies the association between alcohol consumption and GC risk in the Korean population.
Materials and Methods:
Polygenic risk scores for GC (PRS-GC) and alcohol consumption (PRS-Alcohol) were formulated using genome-wide association results from BioBank Japan. Validation was performed using Korean cohorts (SNUBH-GENIE cohort), incorporating 8,846 controls and 531 patients with GC. Subsequently, these PRSs were applied to an independent Korean cohort of 67,771 participants, including 313 patients with GC during the follow-up for 14 years (KoGES cohort).
Results:
In KoGES cohort, the influence of alcohol consumption on GC risk was significantly altered by the PRS-GC and exhibited a synergistic interaction effect. PRS-Alcohol itself shows a negative correlation with GC risk. However, when actual alcohol consumption significantly exceeded genetically predicted levels, the risk of alcohol-related GC was notably increased (adjusted hazard ratio, 1.32; 95% confidence interval, 1.01 to 1.72). Heavy drinkers in the high–PRS-GC/low–PRS-Alcohol group had a 2.16 times higher risk of GC than non-to-light drinkers, which was prominent in males.
Conclusion
Korean drinkers with higher PRS-GC who consume alcohol more than genetically predicted levels are susceptible to GC. PRS-GC and PRS-Alcohol may be beneficial for assessing the impact of alcohol consumption on GC risk in Koreans.
6.Dietary Habits and Diet Quality by Sleep Quality among University Students in Chungcheong
Ye-Eun YOON ; Yujin SONG ; Ji-Won KANG ; Min Ju JO ; Seung-Yeon CHOO ; Mi-Kyeong CHOI ; Yun-Jung BAE
Journal of the Korean Dietetic Association 2026;32(2):72-84
This study examined sleep-related characteristics among university students and the associations between sleep quality, dietary habits, and diet quality.Three hundred and ninety-three university students (206 men and 187 women) enrolled at universities in the Chungcheong region of Korea participated in this study between November and December 2023. Data on the general characteristics, dietary habits, sleep status, and the Nutrition Quotient (NQ) for adults were collected using a structured questionnaire. The sleep quality was assessed using the Pittsburgh Sleep Quality Index– Korean version (PSQI-K). The participants were classified into a good sleeper group (PSQI-K≤5) and a poor sleeper group (PSQI-K≥6). The dietary habits and NQ scores were compared according to the sleep quality. Compared with good sleepers, poor sleepers had a significantly higher prevalence of eating alone at least once per day (P<0.01) and higher scores for unhealthy dietary behaviors, including overeating, eating quickly, a preference for salty food, skipping meals, and irregular meal timing (P<0.05). Although the total NQ scores and balance and practice domain scores did not differ according to sleep quality, the moderation domain scores were significantly lower among poor sleepers, particularly in men (P<0.05). In conclusion, poor sleep quality among university students was associated with unhealthy dietary habits and lower diet quality related to dietary restraint. These findings highlight the importance of improving sleep quality as a part of health education and dietary intervention programs for university students.
7.Data-driven life-stage classification for companion dogs and cats using age-specific diagnosis patterns in South Korea
Jin-Young PARK ; Seogjin KANG ; Yoon Jung DO ; Eun-yeong BOK ; Jong Ryul PARK ; Tae Woo KIM ; Chang-Min LEE ; Woong-Bin RO ; Jang Yeop KIM ; Dong Yun LEE ; Heyong-Seok KIM ; Kyung-Duk MIN
Journal of Veterinary Science 2026;27(1):e5-
Objective:
To classify life stages for companion dogs and cats by identifying clusters in age-specific disease proportions derived from medical records, providing a data-driven foundation for health examination programs.
Methods:
We collected 505,667 medical records from 82 veterinary facilities in South Korea between 2020 and 2023. Diagnoses were standardized using GPT-4o and S-BioBERT. Following preprocessing, data from 27 facilities yielded 222,706 canine and 39,910 feline records for the final analysis. Principal component analysis and K-means clustering (K = 4) were applied to age-specific disease proportions to identify life stages.The 10 most highest-proportion diagnoses diseases were determined for each cluster.
Results:
Canine life stages were classified as ≤ 1 year, 2–5 years, 6–10 years, and 11–15+ years.Feline life stages were 1–2 years, 3–8 years, 9–12 years, and 13–15+ years. In dogs, developmental diseases were common in the youngest age group, while chronic diseases were more prevalent in older groups. In cats, oral and urinary diseases were high-ranking, conjunctivitis was most common in the early stage, and chronic diseases increased with age.
Conclusions
and Relevance: Age-specific diagnosis patterns support four practical life stages for dogs and cats in South Korea. These boundaries can inform evidence-based preventive examination schedules, animal health policy, and pet insurance product design.
8.Integrated genomics and metabolomics to identify cause-specific biomarkers for chronic kidney disease in a Korean population
Min Woo KANG ; Ji-Eun KIM ; Jihyun KANG ; Seonmi KIM ; JooYong PARK ; Sohyun BAE ; Yon Su KIM ; Ji-Yeob CHOI ; Joo-Youn CHO ; Seung Seok HAN
Kidney Research and Clinical Practice 2026;45(1):50-64
Background:
The heterogeneity of chronic kidney disease (CKD) and fragmented analysis methods hinder the precise identification of novel biomarkers. We addressed this challenge using two independent cohorts to integrate genomics and metabolomics, aiming to identify cause-specific biomarkers for CKD in the Korean population.
Methods:
A longitudinal genome-wide association study using the Cox proportional hazards model was conducted using the Ansan and Ansung cohort. To validate these genomic biomarkers and integrate them with plasma metabolomics biomarkers, we utilized a hospital-based biopsy cohort to identify cause-specific CKD biomarkers. Within the biopsy cohort, we analyzed four disease subsets, including type 2 diabetic kidney disease (DKD), hypertensive nephropathy (HN), immunoglobulin A nephropathy (IgAN), and membranous nephropathy (MN), and compared them with healthy individuals. Significant single nucleotide polymorphisms(SNPs) and metabolites for each CKD subset were identified through logistic regression and correlation-based network analyses. Subsequently, we analyzed the risk of disease progression associated with the identified pairs.
Results:
A total of 448 variants associated with CKD occurrence were identified, with significant differences in several genetic variants and metabolites observed among patients with DKD, HN, IgAN, and MN compared to healthy individuals. Among 36 SNP-metabolite pairs, those involing FOXB1 and ZFP42 were associated with DKD, whereas pairs involving MMRN1 and SYNJ2 were linked to MN. Notably, the rs1025170 variant in FOXB1 and tyrosine pair was correlated with DKD progression.
Conclusion
Integrating genomics and metabolomics across independent cohorts enables the discovery of cause-specific biomarkers for the occurrence and progression of CKD in the Korean population.
9.Risk stratification for malignant upgrade in breast atypical hyperplasia: a Korean multi-institutional analysis from academic hospitals
Hyobin KIM ; Jung Ho PARK ; Min Kyoon KIM ; Chihwan CHA ; Hocheol LEE ; Se Jeong OH ; Hoon CHOI ; Jae Pak YI ; Su Hyun LIM ; Eun Young KIM ; Young-Joon KANG
Korean Journal of Clinical Oncology 2026;22(1):18-27
Purpose:
Atypical hyperplasia (AH) management remains controversial due to variable malignant disease progression rates. While Western studies report 10% to 25% upgrade rates, data from Asian populations, particularly from referral academic centers, are limited. We aimed to identify predictive factors for malignant upgrade in Korean women with AH at academic hospitals.
Methods:
This retrospective multi-institutional study analyzed 340 patients diagnosed with AH on initial biopsy who underwent subsequent excision at five Korean academic hospitals from 2000 to 2022. Malignant upgrade was defined as ductal carcinoma in situ or invasive cancer on the final pathology. Multivariate logistic regression was used to identify independent predictors of upgrades.
Results:
Among 340 patients (319 atypical ductal hyperplasia, 20 atypical lobular hyperplasia, and 1 mixed), 128 (37.6%) experienced a malignant upgrade, 98 (76.6%) to ductal carcinoma in situ, and 30 (23.4%) to invasive cancer. In multivariate analysis, multifocal atypia (odds ratio [OR], 25.61; 95% confidence interval [CI], 11.20–58.55; P<0.001) and Breast Imaging-Reporting and Data System 4c-5 lesions (OR, 11.02; 95% CI, 1.43–84.86; P=0.021) were significant predictors. Multifocal atypia showed an 84.4% upgrade rate. Core needle biopsy had higher upgrade rates than vacuum-assisted biopsy (45.2% vs. 20.0%; P<0.001). The upgrade rates decreased from 50% to 25% over the study period (P<0.05).
Conclusion
The 37.6% upgrade rate in this tertiary referral cohort exceeded that in Western reports, with multifocal atypia emerging as the strongest predictor. These findings support immediate excision for multifocal atypia while allowing individualized management for unifocal lesions with favorable imaging in Korean tertiary care settings.
10.Structured Integration of an Artificial Intelligence-Based System for the Optical Diagnosis of Colorectal Polyps
Hae Yeon KANG ; Soonwhan KANG ; Goh Eun CHUNG ; Dong Hoon BAEK ; Hong Sub LEE ; Jinbae PARK ; Sun Young YANG ; Seon Hee LIM ; Ji Min CHOI ; Jung KIM ; Jung Ho BAE
Gut and Liver 2026;20(1):86-96
Background/Aims:
Recent advances in computer-aided diagnosis (CADx) systems have demonstrated expert-level accuracy in the optical diagnosis of colorectal polyps. High-confidence (HC) diagnoses have been defined as those made within 3 seconds without hesitation, and these systems have been shown to improve diagnostic accuracy. We aimed to evaluate the performance of endoscopists with varying levels of experience in diagnosing colorectal polyps with the assistance of a new CADx system applying the 3-second rule and without artificial intelligence assistance.
Methods:
In this multicenter ex vivo study, 35 endoscopists assessed 100 polyps (51 adenomas, 39 hyperplastic polyps, 10 sessile serrated lesions) using narrow-band imaging video clips on an online platform. Assessments consisted of individual endoscopist diagnosis and CADx-assisted diagnosis. HC assignments followed the 3-second rule in both phases. Performance metrics included HC accuracy, HC rate, and adherence to the Preservation and Incorporation of Valuable Endoscopic Innovations (PIVI) and Simple Optical Diagnosis Accuracy (SODA) thresholds.
Results:
HC diagnostic accuracy improved from 78.3% (95% confidence interval [CI], 76.6% to 80.0%) to 89.8% (95% CI, 88.6% to 90.9%) with CADx assistance (p<0.001). The proportion of HC predictions increased from 64.2% to 75.4% (p<0.001). Novice endoscopists showed marked improvement with CADx (74.1% vs 88.8%; p<0.001). CADx-assisted diagnoses nearly met SODA and PIVI thresholds under the 3-second rule. Additional analysis demonstrated that CADx assistance significantly improved interobserver agreement and ground truth, particularly for novices (κ=0.37 to κ=0.65; p<0.001).
Conclusions
Integrating CADx with the 3-second rule significantly enhances the performance of endoscopists in the optical diagnosis of colorectal polyps, with the greatest benefit observed among novice endoscopists.

Result Analysis
Print
Save
E-mail