Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Single room isolation with contact precautions is widely regarded as a fundamental strategy to prevent the transmission of multidrug-resistant organisms (MDROs). However, its implementation demands substantial resources, limiting its universal application to all MDROs. In this study, we assessed the effect of discontinuing single room isolation for vancomycin-resistant Enterococcus (VRE). Methods: This is a retrospective, observational study conducted at a single 750-bed tertiary center. We conducted an interrupted time series analysis to compare incidence rates and trends of new-onset VRE colonization and bacteremia during the one year before and after the strategy change on January 1, 2023. Results: Single-room occupancy decreased from 79.7% pre-intervention to 23.6% postintervention (P < 0.001). The incidence rate of new-onset VRE colonization was 0.452 and 0.535 per 1,000 patient-days in the pre- and post-intervention periods, respectively, with no statistically significant difference (P = 0.202). However, there was a slightly increasing trend (0.036 [95% confidence interval, −0.002, 0.074] increase per month, P = 0.066). The new-onset VRE bacteremia incidence rate was not differed in incidence (0.060 and 0.055, P= 0.571) or trend (P = 0.720). Conclusion Our study suggests that discontinuing single-room isolation for VRE patients may not affect the incidence of new-onset VRE bacteremia, but caution is needed due to the potential increase in colonization.

Background: Single room isolation with contact precautions is widely regarded as a fundamental strategy to prevent the transmission of multidrug-resistant organisms (MDROs). However, its implementation demands substantial resources, limiting its universal application to all MDROs. In this study, we assessed the effect of discontinuing single room isolation for vancomycin-resistant Enterococcus (VRE). Methods: This is a retrospective, observational study conducted at a single 750-bed tertiary center. We conducted an interrupted time series analysis to compare incidence rates and trends of new-onset VRE colonization and bacteremia during the one year before and after the strategy change on January 1, 2023. Results: Single-room occupancy decreased from 79.7% pre-intervention to 23.6% postintervention (P < 0.001). The incidence rate of new-onset VRE colonization was 0.452 and 0.535 per 1,000 patient-days in the pre- and post-intervention periods, respectively, with no statistically significant difference (P = 0.202). However, there was a slightly increasing trend (0.036 [95% confidence interval, −0.002, 0.074] increase per month, P = 0.066). The new-onset VRE bacteremia incidence rate was not differed in incidence (0.060 and 0.055, P= 0.571) or trend (P = 0.720). Conclusion Our study suggests that discontinuing single-room isolation for VRE patients may not affect the incidence of new-onset VRE bacteremia, but caution is needed due to the potential increase in colonization.

Background: This study aimed to evaluate the relationship between clinical experience and death certificate (DC) errors by analyzing DCs written by experienced emergency physicians (EPs). Methods: DCs issued by four experienced EPs over a 10-year period were retrospectively reviewed. DC errors were divided into major and minor errors based on whether they affected the cause of death (COD) determination. The errors were judged through first and second evaluations. Basic information regarding DCs and 10-year changes in DC errors were analyzed. Results: A total of 505 DCs were analyzed, with an average of 34 to 70 for each study year.The number of CODs written in the DCs tended to decrease over time. The presentation of major DC errors did not show a tendency to change over time. However, the sum of the major and minor errors tended to increase over time. Secondary conditions as the underlying COD tended to increase, and the incompatible causal relationships between CODs tended to decrease over time in the detailed analysis of major errors. The increasing tendency for incorrect other significant conditions, incorrect type of accident, incorrect intention of the external cause, no record of the trauma mechanism, and record of the trauma mechanism without another COD were found in the detailed analysis of minor errors. Conclusion DC errors did not decrease as clinical experience increased. Education to reduce DC errors and a feedback process for written DCs are necessary, regardless of clinical experience.

Background: As the prevalence of hypertension increases with age and the proportion of the older population is also on the rise, research on the characteristics of older hypertensive patients and the importance of frailty is necessary. This study aimed to identify clinical characteristics of older hypertension in Korea and to investigate these characteristics based on frailty status. Methods: The HOW to Optimize eLDerly systolic BP (HOWOLD-BP) is a prospective, multicenter, open-label, randomized clinical trial that aims to compare intensive (target systolic blood pressure [SBP] ≤ 130 mmHg) with standard (target SBP ≤ 140 mmHg) treatment to reduce cardiovascular events in older hypertensive Korean patients aged ≥ 65 years. Data were analyzed through a screening assessment of 2,085 patients recruited from 11 university hospitals. Demographic, functional (physical and cognitive), medical history, laboratory data, quality of life, and medication history of antihypertensive drugs were assessed. Results: The mean age was 73.2 years (standard deviation ± 5.60), and 48.0% (n = 1,001) were male. Prevalent conditions included dyslipidemia (66.5%), obesity (body mass index ≥ 25 kg/m 2 , 53.6%), and diabetes (28.9%). Dizziness and orthostatic hypotension were self-reported by 1.6% (n = 33) and 1.2% (n = 24), respectively. The majority of patients were on two antihypertensive drugs (48.4%), while 27.5% (n = 574) and 20.8% (n = 433) were on 1 and 3 antihypertensive medications, respectively. Frail to pre-frail patients were older and also tended to have dependent instrumental activities of daily living, slower gait speed, weaker grip strength, lower quality of life, and lower cognitive function. The frail to pre-frail group reported more dizziness (2.6% vs. 1.2%, P < 0.001) and had concerning clinical factors, including lower glomerular filtration rate, more comorbidities such as diabetes, stroke, and a history of admission. Frail to pre-frail older hypertensive patients used slightly more antihypertensive medications than robust older hypertensive patients (1.95 vs. 2.06, P = 0.003). Pre-frail to frail patients often chose beta-blockers as a third medication over diuretics. Conclusion This study described the general clinical characteristics of older hypertensive patients in Korea. Frail hypertensive patients face challenges in achieving positive clinical outcomes because of multifactorial causes: they are older, have more morbidities, decreased function, lower quality of life and cognitive function, and take more antihypertensive medications. Therefore, it is essential to comprehensively evaluate and monitor diseaserelated or drug-related adverse events more frequently during regular check-ups, which is necessary for pre-frail to frail older patients with hypertension.

We aimed to characterize the genomes of monkeypox virus isolates from the Far East, providing insights into viral transmission and evolution. Genomic analysis was conducted on 8 isolates obtained from patients with monkeypox virus disease in the Republic of Korea between May 2022 and early 2023. These isolates were classified into Clade IIb. Distinct lineages, including B.1.1, A.2.1, and B.1.3, were observed in 2022 and 2023 isolates, with only the B.1.3 lineage detected in six isolates of 2023. These genetic features were specific to Far East isolates (the Republic of Korea, Japan, and Taiwan), distinguishing them from the diverse lineages found in the Americas, Europe, Africa, and Oceania. In early 2023, the prevalence of the B.1.3 lineage of monkeypox virus identified in six patients with no overseas travel history is considered as an indicator of the potential initiation of local transmission in the Republic of Korea.

Background: Acellular dermal matrices (ADMs) have shown promise in promoting tissue regeneration; however, their integration in challenging cases with limited vertical-axis neovascularization remains difficult. This study investigates whether clinically meaningful transverse-axis neovascularization is identified in ADM engraftment and whether this can be further accelerated by platelet-rich plasma (PRP). Methods: ADM and PRP-soaked ADM were implanted into New Zealand rabbits, and histological analysis was performed at different periods to compare neovascularization. Results: Histological analysis revealed that among 32 biopsy sites, there was transverse-axis neovascularization with an average length of 606.89 μm. When divided into two groups for assessing the impact of PRP on transverse-axis neovascularization, the extent of such neovascularization was measured as 582.99 μm in the control group and 630.79 μm in the experimental group. However, there was no statistically significant difference between the two groups (P=0.693). Conclusion The results of the present study indicate that achieving meaningful transverse-axis neovascularization in implanted ADMs remains a challenge, warranting further investigation into ADM structure and vertical-axis neovascularization.