1.Detection of Fusion Genes Using RNA Sequencing in Acute Leukemia
Hyun-Young KIM ; Boram KIM ; Min-Seung PARK ; Jong-Ho PARK ; Hee Young JU ; Keon Hee YOO ; Jun Ho JANG ; Chul Won JUNG ; Hee-Jin KIM
Annals of Laboratory Medicine 2026;46(3):257-269
Background:
Fusion genes are major drivers of acute leukemia. Conventional diagnostics are limited in detecting the diverse fusions included in recently updated acute leukemia classifications. We evaluated the fusion detection performance of RNA sequencing (RNAseq) compared with that of conventional diagnostics in patients with acute leukemia.
Methods:
We retrospectively obtained the data of 101 patients with acute leukemia who underwent conventional diagnostics (i.e., karyotyping, FISH, or multiplex reverse transcription PCR) at diagnosis at Samsung Medical Center, Seoul, Korea, between September 2022 and September 2023. Whole RNA-seq was performed using the Illumina Stranded mRNA Prep kit (Illumina, San Diego, CA, USA). The concordance, sensitivity, and specificity of RNA-seq for fusion gene detection were compared with those of conventional diagnostics.
Results:
RNA-seq helped identify 52 fusion genes in 51 (50.5%) of 101 patients, with detection rates of 40.7%, 70.3%, 37.5%, and 50% in acute myeloid leukemia, B-cell acute lymphoblastic leukemia, T-cell acute lymphoblastic leukemia, and mixed-phenotype acute leukemia, respectively. RNA-seq showed 83.3% sensitivity and 80.8% concordance with conventional diagnostics; it missed eight fusions, likely because of low transcript abundance or enhancer hijacking. RNA-seq also helped clarify three previously unspecified rearrangements and detected 12 fusions (21.4%) in 56 cases that tested negative with conventional diagnostics, including four novel (KMT2A::THAP12 , RUNX1::PRPF19 , MLLT10::UBE2L6, and FUS::ZNF362) and three rare (HNRNPH1::ERG, RUNX1::USP42, and ETV6::NCOA2) fusions.
Conclusions
This was the first study to evaluate the performance of whole RNA-seq in fusion detection in patients with acute leukemia in Korea. Incorporating RNA-seq into diagnostic workflows may facilitate earlier and more precise therapeutic decisions and improve prognostic assessment in patients with acute leukemia.
3.Clinical Outcomes and Use of Implantable Cardioverter-Defibrillator in Ischemic Heart Failure Patients with Reduced Ejection Fraction:A Retrospective Observational Study
Kyung Hoon CHO ; Ki Hong LEE ; Yong-Kyu LEE ; Seok OH ; Yongwhan LIM ; Joon Ho AHN ; Seung Hun LEE ; Dae Young HYUN ; Min Chul KIM ; Doo Sun SIM ; Young Joon HONG ; Ju Han KIM ; Youngkeun AHN ; Jang Hoon LEE ; Joo-Yong HAHN ; Yu-Ri KIM ; Nam Sik YOON ; Hyung Wook PARK ; Weon KIM ; Myung Ho JEONG ;
Chonnam Medical Journal 2026;62(2):55-63
Limited data exist regarding the real-world practices and clinical outcomes in patients with ischemic heart failure with reduced left ventricular ejection fractions (LVEFs).Using nationwide registry data from South Korea, we aimed to investigate long-term outcomes and clinical practices, especially implantable cardioverter defibrillators (ICDs) implantation, in patients with reduced LVEFs at least 40 days after acute myocardial infarction (AMI). Of 13,056 patients with AMI between 2011 and 2015, we analyzed 350 (median age, 66 years [interquartile range, 56-75]) who had LVEFs <40% on follow-up transthoracic echocardiogram 40 days after the index event. The primary outcome was cardiac-cause mortality at 3 years. Secondary outcomes comprised major cardiovascular events as well as outcomes defined by the use of ICDs, cardiac resynchronization therapy defibrillators (CRT-Ds), and electrophysiology studies. Among 350 patients, 39 (11.1%) died from cardiac causes during 3 years of follow-up. Eleven (3.1%) were hospitalized for ventricular tachycardia. The rate of ICD or CRT-D implantation up to 3 years was 5.7% (20/350). Cox time-to-event analysis revealed older age, LVEF <30%, diabetes mellitus, and previous MI or revascularization as positively associated with cardiac death, whereas the use of statins and body weight <67 kg were negatively associated. This nationwide Korean registry demonstrated that only 5.7% of patients who had reduced LVEFs after 40 days of AMI underwent ICD implantations over 3 years. Considering the high mortality, concerted efforts are needed to improve clinical outcomes for patients who may have been candidates for ICD implantation.
4.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.
5.Associated factors of osteoporosis and the impact of osteoporosis on all-cause mortality in incident hemodialysis older patients
Seunghye LEE ; Yoomee KANG ; Yu Ah HONG ; Sung Joon SHIN ; Soon Hyo KWON ; Sungjin CHUNG ; Young Youl HYUN ; Sang Heon SONG ; Jae Won YANG ; Won Min HWANG ; Jang-Hee CHO ; Kyung Don YOO ; In O SUN ; Gang-Jee KO ; Byung Chul YU ; Hyunsuk KIM ; Woo Yeong PARK ; Tae Won LEE ; Dong Jun PARK ; Eunjin BAE ;
Kidney Research and Clinical Practice 2026;45(1):110-119
Background:
With the aging population and advancements in medical care worldwide, the number of older patients with end-stage kidney disease continues to rise. This study aimed to identify factors associated with osteoporosis and osteopenia in older patients undergoing incident hemodialysis and assess their impact on mortality.
Methods:
We analyzed a large multicenter retrospective cohort of patients aged ≥70 years undergoing incident hemodialysis to identify factors associated with osteoporosis using logistic regression analysis and to assess the association of death with osteoporosis and osteopenia using Cox multivariable analysis.
Results:
Among 710 patients, 39.0% and 19.6% had osteoporosis and osteopenia, respectively. Osteoporosis was significantly associated with female sex, a history of fractures, and the absence of phosphate binder use. During a median follow-up of 36.8 months, 348 participants (58.8%) died. Mortality rates were the highest in the osteoporosis group (79.8%), followed by the osteopenia (77.2%) and normal bone mineral density (BMD) groups (35.2%). Cox regression analysis revealed that even after adjusting for covariates, the osteoporosis group was significantly associated with a higher mortality risk than the normal BMD group. Osteoporosis at the start of hemodialysis was significantly associated with higher mortality.
Conclusion
We should consider the importance of bone health in patients undergoing incident hemodialysis and pay attention to the use of phosphate binders and fracture prevention.
6.Impact of obesity on renal function in elderly Korean adults: a national population-based cohort study
Jihyun YANG ; Hui Seung LEE ; Chi-Yeon LIM ; Hyunsuk KIM ; Sungjin CHUNG ; Soon Hyo KWON ; Jang-Hee CHO ; Kyung Don YOO ; Woo Yeong PARK ; In O SUN ; Byung Chul YU ; Gang-Jee KO ; Jae Won YANG ; Won Min HWANG ; Sang Heon SONG ; Sung Joon SHIN ; Yu Ah HONG ; Eunjin BAE ; Young Youl HYUN
Kidney Research and Clinical Practice 2026;45(1):65-76
Background:
Obesity is a well-known risk factor for chronic kidney disease and its progression. However, the impact of obesity on the renal function of the elderly population is uncertain. We investigated the association between obesity and renal outcomes in the elderly.
Methods:
We analyzed 130,504 participants from the Korean National Health Insurance Service-Senior cohort. Obesity was classified according to body mass index (BMI), sex-specific waist circumference (WC), and the presence of metabolic syndrome. The primary outcome was renal function decline, defined as a decline in the estimated glomerular filtration rate (eGFR) of at least 50% from baseline or new-onset end-stage renal disease.
Results:
During a follow-up period of 559,531.1 person-years (median, 4.3 years), 2,486 participants (19.0%; incidence rate of 4.44 per 1,000 person-years) showed renal function decline. A multivariate Cox proportional hazards model revealed that BMI/WC was not associated with renal function decline. However, the group with metabolic syndrome had a significantly increased risk of renal function decline compared to the group without metabolic syndrome (adjusted hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.13–1.36). Compared with the non-metabolic syndrome group, the adjusted HRs (95% CI) for participants with one through five components were 0.96 (0.84–1.11), 1.10 (0.96–1.27), 1.24 (1.06–1.45), 1.37 (1.12–1.66), and 1.99 (1.42–2.79), respectively (p for trend < 0.001).
Conclusion
In elderly Korean adults, metabolic syndrome and the number of its components were associated with a higher risk of renal function decline, but BMI or WC was not significant.
7.Incidence of Chronic Kidney Disease According to Steatotic Liver Disease and Its Subclassifications: A Longitudinal Cohort Study
Aryoung KIM ; Danbee KANG ; Sung Chul CHOI ; Dong Hyun SINN ; Hye Ryoun JANG ; Geum-Youn GWAK
Gut and Liver 2026;20(1):117-124
Background/Aims:
Chronic kidney disease (CKD) is a significant health problem worldwide, and identifying risk factors for CKD is crucial. We investigated the association between steatotic liver disease (SLD) and the incidence of CKD.
Methods:
This longitudinal cohort study involved 70,361 adults who did not have CKD at baseline and who underwent at least two health checkups. SLD status was assessed via ultrasonography. The severity of SLD was determined using the Fibrosis-4 score. CKD was defined as an estimated glomerular filtration rate <60 mL/min/1.73 m 2 .
Results:
Over 475,835 person-years (mean 6.8 years), 2,723 participants developed CKD.The adjusted hazard ratio (aHR) for development of CKD in participants with SLD compared to those without SLD was 1.17 (95% confidence interval [CI], 1.08 to 1.27), with the risk increasing with SLD severity. The aHR (95% CI) for incident CKD was 0.84 (0.51 to 1.37) for cryptogenic SLD, 1.25 (1.16 to 1.36) for metabolic dysfunction-associated SLD (MASLD), and 1.32 (1.01 to 1.73) for metabolic dysfunction-associated alcoholic liver disease (MetALD) compared with participants without SLD. Within these SLD subclassifications, the risk of CKD development was increased as disease severity advanced.
Conclusions
SLD was linked to a higher incidence of CKD, with the CKD risk increasing sequentially from cryptogenic SLD to MASLD and MetALD. Advanced fibrosis in each SLD subclassification further increases the risk of CKD. Stratifying SLD according to metabolic dysfunction, significant alcohol intake, and fibrosis severity may help identify and monitor individuals at high risk of developing CKD.
8.Remission of diabetes with glutamic acid decarboxylase antibody positivity that developed after the administration of olanzapine: a case report
Kyuho KIM ; Soo Hyun SEO ; Yun Ji HONG ; Woojae MYUNG ; Bomi KIM ; Chang Ho AHN ; Sung Hee CHOI ; Hak Chul JANG ; Tae Jung OH
Precision and Future Medicine 2026;10(1):51-56
Olanzapine is a second-generation antipsychotic drug associated with the development of type 2 diabetes. However, the development and remission of diabetes with glutamic acid decarboxylase (GAD) antibody (Ab) positivity related to olanzapine treatment have not been reported. Here, we present the case of a 33-year-old man taking olanzapine who was diagnosed with diabetes with GAD Ab positivity complicated by diabetic ketoacidosis (DKA). After discontinuation of the drug and tight glycemic control, his diabetes remitted, and the GAD Ab became negative spontaneously after 18 months. The classification of diabetes is challenging because of overlapping autoimmune and metabolic features. Olanzapine may have contributed to pancreatic β-cell apoptosis, which could potentially trigger autoimmunity and the development of type 1 diabetes-like features (DKA as the initial presentation, a low C-peptide level, and GAD Ab positivity). The rapid amelioration of hyperglycemia and weight reduction may be responsible for the remission of diabetes after the discontinuation of olanzapine.
9.Validation of Devices for the Five Times Sit To Stand Test:Comparing Plantar Pressure and Head Motion Analysis with Manual Measurement
Sanghyun JEE ; Chan Woong JANG ; Kyoungmin PARK ; Sanghoon SHIN ; Min-Chul PAEK ; Jung Hyun PARK
Yonsei Medical Journal 2025;66(1):51-57
Purpose:
This study aims to evaluate a new method for the five times sit to stand test (FTSST), crucial for addressing frailty in an aging population. It utilizes a smart insole for plantar pressure analysis and a marker-less motion capture device for head height analysis.
Materials and Methods:
Thirty-five participants aged 50 years or older underwent FTSST assessment using three methods: manual measurement with a stopwatch (FTSST-M), plantar pressure analysis with smart insoles (FTSST-P), and head height analysis with a marker-less motion capture device (FTSST-H). Simultaneous measurements using three methods were done. Correlation between results of these methods were analyzed using intraclass correlation coefficient (ICC) and κ coefficient. Comprehensive clinical examinations were conducted with ethical approval.
Results:
Participants’ mean scores for FTSST-M, FTSST-P, and FTSST-H were 2.43±1.20, 2.43±1.29, and 2.37±1.31, respectively. Correlations of the times and corresponding scores between FTSST-P and FTSST-M, as well as FTSST-H and FTSST-M, exceeded 0.9 (ICC and κ coefficients, p<0.001). Using an FTSST score of 3 or less to indicate vulnerability, the κ value for vulnerability classification between two measurements was 0.886 (p<0.001).
Conclusion
This study showed strong correlation between FTSST results using smart insoles and marker-less motion capture, compared to conventional methods. These findings highlight the potential of these technologies for precise FTSST measurements, offering convenience and cost-effectiveness. Simultaneous use of these devices enables diverse analyses, enhancing our understanding of frailty.
10.Rare Non-Cryptic NUP98 Rearrangements Associated With Myeloid Neoplasms and Their Poor Prognostic Impact
Min-Seung PARK ; Boram KIM ; Jun Ho JANG ; Chul Won JUNG ; Hee-Jin KIM ; Hyun-Young KIM
Annals of Laboratory Medicine 2025;45(1):53-61
Background:
NUP98 rearrangements (NUP98r), associated with various hematologic malignancies, involve more than 30 partner genes. Despite their clinical significance, reports on the clinicopathological characteristics of rare NUP98r remain limited. We investigated the characteristics of patients with myeloid neoplasms harboring NUP98r among those identified as having 11p15 translocation in chromosomal analysis.
Methods:
We retrospectively reviewed results from bone marrow chromosomal analyses conducted between 2011 and 2023 and identified 15 patients with 11p15 translocation.Subsequently, NUP98r were evaluated using FISH and/or reverse transcription PCR, and clinical and laboratory data of the patients were analyzed.
Results:
NUP98r were identified in 11 patients initially diagnosed as having AML (N = 8), myelodysplastic syndrome (N = 2), or chronic myelomonocytic leukemia (N = 1), with a median age of 44 yrs (range, 4–77 yrs). Three patients had a history of chemotherapy. In total, five NUP98 fusions were identified: NUP98::DDX10 (N = 3), NUP98::HOXA9 (N = 2), NUP98::PSIP1 (N = 2), NUP98::PRRX1 (N = 1), and NUP98::HOXC11 (N = 1). Patients with NUP98r exhibited a poor prognosis, with a median overall survival of 12.0 months (95% confidence interval [CI], 3.4–29.6 months) and a 5-yr overall survival rate of 18.2% (95% CI, 5.2%–63.7%).
Conclusions
Our study revealed the clinical and genetic characteristics of patients with myeloid neoplasms harboring rare and non-cryptic NUP98r. Given its association with poor prognosis, a comprehensive evaluation is crucial for identifying previously underdiagnosed NUP98r in patients with myeloid neoplasms.

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