Background: In South Korea, nontuberculous mycobacteria (NTM) is not a notifiable disease, while the absence of a national surveillance system hampers accurate assessment of its incidence. Therefore, this study utilized National Health Insurance Service (NHIS) claims data to investigate nationwide trends in NTM occurrence over the past decade. Methods: We used NHIS claims (2010−2022) to assemble a cohort with International Classification of Diseases, 10th Revision A31 (A31.0, A31.1, A31.8, A31.9). For incidence, cases diagnosed in 2010−2011 were excluded. Incidence was estimated under three definitions: ≥2 outpatient visits or ≥1 inpatient admission with A31 during the study period; same as A, but with ≤180 days between visits; meeting B plus ≥1 antibiotic prescription within 180 days (treatment initiation). Age-standardized prevalence and incidence were calculated using the 2010 Korean population. Results: A total of 178,287 newly diagnosed NTM cases were identified from 2012 to 2022 (mean age 51.4 years; 66.8 % female). The age-standardized prevalence increased from 15.5 to 69.8 per 100,000 in 2010 to 2022. Incidence peaked in 2017 (38.9/100,000), then declined to 26.9 in 2022. Age-specific incidence of NTM infection showed distinct sex-related patterns. Among men, incidence was consistently concentrated in older adults, particularly those ≥80 years, throughout 2012−2022. In contrast, women experienced a marked epidemiologic shift beginning in 2017, with incidence in their 20s and 30s surpassing older age groups. Medical Aid beneficiaries consistently showed higher incidence rates. By region, Daejeon and Chungnam showed the greatest increase in incidence rates in 2022, compared to 2012. Conclusion NTM infection is increasing in Korea, with distinct epidemiologic patterns by sex, age, and socioeconomic status. The rising burden, especially among young women and the socioeconomically disadvantaged, warrants targeted public health strategies.

Background and Objectives: Clinical characteristics and outcomes in acute heart failure (AHF) vary by phenotype. We assessed phenotype-specific features, treatment patterns, and outcomes in a nationwide Korean cohort. Methods: The Korean Heart Failure III registry prospectively enrolled 7,351 AHF admissions at 47 hospitals. Among 6,777 patients with available left ventricular ejection fraction (EF), phenotypes were defined as heart failure with reduced EF (HFrEF, ≤40%), mildly reduced EF (HFmrEF,41–49%), or preserved EF (HFpEF, ≥50%). The primary endpoint was a 12-month composite of all-cause death or heart transplantation, evaluated from index admission and, among hospital survivors, from discharge. We used inverse probability weighting (multinomial generalized boosted models with stabilized, trimmed weights) and weighted Cox proportional-hazards models to estimate hazard ratios (HRs). Results: Phenotype distribution was 58.9% HFrEF, 13.6% HFmrEF, and 27.5% HFpEF. Crude 12-month composite rates from index admission were 13.4% (HFrEF), 12.7% (HFmrEF), and 16.8% (HFpEF). After weighting, from index admission, HFmrEF (HR, 0.892; 95% confidence interval [CI], 0.731–1.088) and HFpEF (HR, 1.101; 95% CI, 0.939–1.291) did not differ from HFrEF; from discharge, HFpEF had modestly higher risk (HR, 1.207; 95% CI, 1.008–1.445) whereas HFmrEF did not (HR, 1.039; 95% CI, 0.844–1.279). Hyponatremia and chronic kidney disease were consistent adverse markers, while angiotensin-converting enzyme inhibitor/ angiotensin II receptor blocker use at discharge was protective. Conclusions Across the EF spectrum, phenotypes showed distinct profiles and risk. Postdischarge risk was modestly higher in HFpEF, supporting phenotype-tailored care and systematic discharge optimization in Korean patients with AHF.

Purpose: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.

Stoma formation for fecal diversion is a common procedure in patients with various complicated conditions after colorectal surgery, such as anastomotic leakage. The singleincision laparoscopic approach for stoma creation offers several advantages, including a reduction in surgical wounds and related complications as well as optimal visualization of the surgical field. This video demonstrates a single-port–assisted diverting ileostomy in a 61-yearold man with anastomotic leakage following low anterior resection for advanced rectal cancer.

Objectives: This study was performed to evaluate the utilization patterns of acid suppressants following the withdrawal of ranitidine in Korea. Methods: Health Insurance Review & Assessment Service (HIRA) data from January 2016 to May 2023 were utilized to assess the usage of histamine H2 receptor antagonists (H2RAs) and proton pump inhibitors (PPIs) for acid-related diseases. Drug utilization was calculated for each agent based on the defined daily dose (DDD). To evaluate changes in utilization following the ranitidine recall, an interrupted time series analysis was conducted using segmented linear regression and an autoregressive integrated moving average model. Results: Before the withdrawal of ranitidine, the DDD per 100 000 inhabitants per day was increasing by 6.9 (95% confidence interval [CI], 4.7 to 9.0) for H2RAs and by 19.3 (95% CI, 16.9 to 21.8) for PPIs each month. After the recall, H2RA utilization immediately declined by -1041.7 (95% CI, -1115.8 to -967.7), followed by a monthly increase of 6.6 (95% CI, 3.7 to 9.6) above the previous trend. PPI utilization temporarily surged by 235.2 (95% CI, 149.1 to 321.3), then displayed a monthly increase of 4.1 (95% CI, 0.7 to 7.6) on top of the pre-recall trend. Among PPIs, esomeprazole and rabeprazole demonstrated notable increases, representing the most commonly used acid suppressants in 2023. Conclusions PPI usage rose prominently following the withdrawal of ranitidine from the market. Considering the potential adverse effects of PPIs, further research is necessary to evaluate the public health implications of shifts in the utilization of acid suppressants.

Purpose: This study aimed to develop a comprehensive practical guide for enteral nutrition (EN) designed to enhance patient safety and reduce complications in Korea. Under the leadership of the Korean Society for Parenteral and Enteral Nutrition (KSPEN), the initiative sought to standardize EN procedures, improve decision-making, and promote effective multidisciplinary communication. Methods: The KSPEN EN committee identified key questions related to EN practices and organized them into seven sections such as prescribing, delivery route selection, formula preparation, administration, and quality management. Twenty-one experts, selected based on their expertise, conducted a thorough literature review to formulate evidence-based recommendations. Drafts underwent peer review both within and across disciplines, with final revisions completed by the KSPEN Guideline Committee. The guide, which will be published in three installments, addresses critical elements of EN therapy and safety protocols. Results: The practical guide recommends that EN orders include detailed elements and advocates the use of electronic medical records for communication. Standardized prescription forms and supplementary safety measures are outlined. Review frequency is adjusted according to patient condition—daily for critically ill or unstable patients and as dictated by institutional protocols for stable patients. Evidence indicates that adherence to these protocols reduces mortality, complications, and prescription errors. Conclusion The KSPEN practical guide offers a robust framework for the safe delivery of EN tailored to Korea’s healthcare context. It emphasizes standardized protocols and interdisciplinary collaboration to improve nutritional outcomes, patient safety, and operational efficiency. Rigorous implementation and monitoring of adherence are critical for its success.

Purpose: Cancer poses a significant global health challenge, demanding precise genomic testing for individualized treatment strategies. Targeted-panel sequencing (TPS) has improved personalized oncology but often lacks comprehensive coverage of crucial cancer alterations. Whole-genome sequencing (WGS) addresses this gap, offering extensive genomic testing. This study demonstrates the medical potential of WGS. Materials and Methods: This study evaluates target-enhanced WGS (TE-WGS), a clinical-grade WGS method sequencing both cancer and matched normal tissues. Forty-nine patients with various solid cancer types underwent both TE-WGS and TruSight Oncology 500 (TSO500), one of the mainstream TPS approaches. Results: TE-WGS detected all variants reported by TSO500 (100%, 498/498). A high correlation in variant allele fractions was observed between TE-WGS and TSO500 (r=0.978). Notably, 223 variants (44.8%) within the common set were discerned exclusively by TE-WGS in peripheral blood, suggesting their germline origin. Conversely, the remaining subset of 275 variants (55.2%) were not detected in peripheral blood using the TE-WGS, signifying them as bona fide somatic variants. Further, TE-WGS provided accurate copy number profiles, fusion genes, microsatellite instability, and homologous recombination deficiency scores, which were essential for clinical decision-making. Conclusion TE-WGS is a comprehensive approach in personalized oncology, matching TSO500’s key biomarker detection capabilities. It uniquely identifies germline variants and genomic instability markers, offering additional clinical actions. Its adaptability and cost-effectiveness underscore its clinical utility, making TE-WGS a valuable tool in personalized cancer treatment.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

Purpose: The associated factors for hypertensive retinopathy (HTR) are rarely investigated. This study aimed to identify the associated factors for HTR using a systematic review. Methods: The review included cross-sectional, case-controlled, and cohort studies on HTR risk factors published in Korean and English with full texts available from PubMed, Embase, CINAHL, Web of Science, and Korean databases. Methodological quality was assessed using the Joanna Briggs Institute (JBI) checklist. Results: Eleven studies were finally selected, and three studies including patients with hypertension without diabetes mellitus, older age, male sex, alcohol consumption, the duration of hypertension, hyperglycemia, dyslipidemia, microalbuminuria, high creatinine levels, chronic kidney disease, and cardiovascular changes were identified as factors associated with HTR. Conversely, in the remaining eight studies, younger age, non-smoking status, and renal function indicators (albuminuria, high creatinine levels, chronic kidney disease, and uric acid) were identified as associated factors. Conclusions Regardless of the inclusion of patients with diabetes mellitus, impaired kidney functions were determined as significant factors associated with retinopathy in patients with HTR. However, considering a limited number of evidence and lack of evidence to confirm causality, we recommend further research on renal function and HTR.