Background: Sapovirus is an increasingly recognized cause of acute gastroenteritis (AGE).Despite its significance, data on sapovirus epidemiology and genetic diversity in Korea are limited. Therefore, we examined sapovirus positivity rates over a 6.5-yr period and analyzed the genetic diversity of strains detected in 2022 in Korea. Methods: We retrospectively analyzed 204,563 sapovirus multiplex PCR test results from suspected AGE cases collected between 2017 and 2023 at two institutions. Monthly and age-specific positive rates were evaluated. Forty sapovirus-positive samples from 2022 were genotyped using reverse transcription PCR and sequencing. The sequences were compared with those in the National Center for Biotechnology Information Virus database, and a phylogenetic tree was constructed to assess genetic relationships among sapovirus strains. Results: The overall sapovirus positivity rate from 2017 to 2023 was 2.2%, with an increasing trend in summer and autumn, except during the coronavirus disease 2019 (COVID-19) pandemic in 2020 and 2021, when sapovirus was rarely detected. Positivity markedly increased in the summer and autumn of 2022 and 2023 following the COVID-19 pandemic. The predominant genotypes in 2022 were GI.1 and GII.3. Phylogenetic analysis revealed genetic diversity among circulating strains. Conclusions This study highlights the rising incidence of sapovirus in Korea, particularly after the COVID-19 pandemic. Despite focusing on genotyping data from a single year, these findings emphasize the need for ongoing surveillance to monitor sapovirus evolution and its public health impact. Additionally, our findings provide essential baseline data for future research into the epidemiology and genetics of sapovirus.

Background: Chromosomal alterations serve as diagnostic and prognostic markers in acute leukemia. Given the evolving landscape of chromosomal abnormalities in acute leukemia, we previously studied these over two periods. In this study, we investigated the frequency of these abnormalities and clinical trends in acute leukemia in Korea across three time periods. Methods: We retrospectively analyzed data from 1,787 patients with acute leukemia (319 children and 1,468 adults) diagnosed between 2006 and 2020. Conventional cytogenetics, FISH, and multiplex quantitative PCR were used for analysis. The patient groups were divided according to the following three study periods: 2006–2009 (I), 2010–2015 (II), and 2016–2020 (III). Results: Chromosomal aberrations were detected in 92% of patients. The PML::RARA translocation was the most frequent. Over the 15-yr period, chromosomal aberrations showed minimal changes, with specific fusion transcripts being common among patients.ALL was more prevalent in children than in adults and correlated significantly with the ETV6::RUNX1 and RUNX1::RUNX1T1 aberrations. The incidence of ALL increased during the three periods, with PML::RARA remaining common. Conclusions The frequency of chromosomal abnormalities in acute leukemia has changed subtly over time. Notably, the age of onset of adult AML has continuously increased. Our results may help in establishing diagnoses and clinical treatment strategies and developing various molecular diagnostic platforms.

Positional information plays a crucial role in embryonic pattern formation, yet its role in tooth development remains unexplored. In this study, we investigated the regional specification of lingual and buccal dental mesenchyme during tooth development. Tooth germs at the cap stage were dissected from mouse mandibles, and their lingual and buccal mesenchymal regions were separated for bulk RNA sequencing. Gene ontology analysis revealed that odontogenesis, pattern specification, and proliferation-related genes were enriched in the lingual mesenchyme, whereas stem cell development, mesenchymal differentiation, neural crest differentiation, and regeneration-related genes were predominant in the buccal mesenchyme. Reaggregation experiments using Wnt1^creERT/+; R26R^tdT/+ and WT mouse models demonstrated that lingual mesenchyme contributes to tooth formation, while buccal mesenchyme primarily supports surrounding tissues. Furthermore, only the lingual part of tooth germs exhibited odontogenic potential when cultured in vitro and transplanted under the kidney capsule. Bulk RNA transcriptomic analysis further validated the regional specification of the lingual and buccal mesenchyme. These findings provide novel insights into the molecular basis of positional information in tooth development and pattern formation.
Animals ; Mice ; Odontogenesis/genetics* ; Tooth Germ/cytology* ; Mesoderm/cytology* ; Cell Differentiation ; Mesenchymal Stem Cells ; Tooth/embryology*

Purpose: This study aimed to examine changes in nurse staffing grades and nursing fee revenues in intensive care units (ICUs) following the third amendment of the resource-based relative value scale, which was implemented in January 2024. Methods: Changes in staffing grades from the fourth quarter of 2023 to the first quarter of 2024 were analyzed among 588 general ICUs, 94 neonatal ICUs, and 13 pediatric ICUs. Annual nursing fee revenues per nurse were estimated based on the new nursing fee structure for each grade. Results: In general ICUs, the highest grade (grade S) and the second-highest grade (grade A) accounted for 7.3% and 41.5%, respectively, in tertiary hospitals, whereas 3.8% were grade S and 11.5% were grade A in general hospitals. In neonatal ICUs, the proportion of higher grades (S, A, and 1) was greater in general hospitals (54.3%) than in tertiary hospitals (38.6%). In pediatric ICUs, 30.8% were grade S and 61.5% were grade A. When applying the same grading criteria (i.e., beds per nurse) across both quarters, staffing levels remained unchanged in most ICUs. Nursing fees and their revenues did not increase proportionally to staffing requirements (i.e., the number of nurses required per patient). Conclusion Revisions to staffing grade and nursing fee systems are necessary to induce medical institutions to improve their ICU staffing levels.

Background: Shortage of organ donors in the Republic of Korea has become a major problem. To address this, it has been questioned whether heart transplant (HTx) allocation should be modified to reduce priority of older patients. We aimed to evaluate post-HTx outcomes according to recipient age and specific pre-HTx conditions using a nationwide prospective cohort. Methods: We analyzed clinical characteristics of 628 patients from the Korean Organ Transplant Registry who received HTx from January 2015 to December 2020. Enrolled recipients were divided into three groups according to age. We also included comorbidities including ambulatory status. Non-ambulatory status was defined as pre-HTx support with either extracorporeal membrane oxygenation, continuous renal replacement therapy, or mechanical ventilation. Results: Of the 628 patients, 195 were < 50 years, 322 were 50–64 years and 111 were ≥ 65years at transplant. Four hundred nine (65.1%) were ambulatory and 219 (34.9%) were nonambulatory. Older recipients tended to have more comorbidities, ischemic cardiomyopathy, and received older donors. Post-HTx survival was significantly lower in older recipients (P = 0.025) and recipients with non-ambulatory status (P < 0.001). However, in contrast to non-ambulatory recipients who showed significant survival differences according to the recipient’s age (P = 0.004), ambulatory recipients showed comparable outcomes (P = 0.465). Conclusion Our results do not support use of age alone as an allocation criterion. Transplant candidate age in combination with some comorbidities such as non-ambulatory status may identify patients at a sufficiently elevated risk at which suitability of HTx should be reconsidered.

Background: In 2023, we experienced an outbreak from a case of undiagnosed crusted scabies, resulting in a significant number of exposed individuals and secondary cases. In this report, we describe the outbreak control measures, the attack rate, and the risk factors for acquisition of scabies among healthcare workers (HCWs). Methods: This study was conducted in a 2,700-bed tertiary care hospital in Seoul, South Korea. The attack rate was defined both for microscopic proven cases per exposed individuals and as the sum of proven and probable cases per exposed individuals. Outbreak control measures included identifying and treating all potentially exposed individuals with or without symptoms, as well as environmental disinfection. Results: From the index, there was potential quinary transmission resulting in 63 proven cases, 142 probable cases, and a total of 1,820 exposed individuals, including 734 contacts from the index case. The attack rate from the index was 7% (50/734) based on proven cases and 19% (138/734) based on proven and probable cases. Among the 526 HCWs who received preemptive topical treatment with permethrin applied once, 21 (4%) were later diagnosed as scabies. In addition, 5 of 20 HCWs (25%) with initial proven scabies had a persistent positive microscopic exam after four permethrin treatments. In the case group, there were significantly more nurses (60% vs. 43%, P = 0.007) and nurse assistants (20% vs. 9%, P = 0.006). There were significantly more cases than controls involving direct contact with the index case (94% vs. 64%, P < 0.001). Conclusion Lowering the threshold for suspicion of crusted scabies is important, as a single missed case could lead to a large outbreak. Simultaneously applying preemptive permethrin cream to all potentially exposed individuals might have been effective in preventing further transmission. However, caution is needed because the development of scabies or persistent scabies is possible even with preemptive or therapeutic treatment.

Purpose: This study aimed to examine changes in nurse staffing grades and nursing fee revenues in intensive care units (ICUs) following the third amendment of the resource-based relative value scale, which was implemented in January 2024. Methods: Changes in staffing grades from the fourth quarter of 2023 to the first quarter of 2024 were analyzed among 588 general ICUs, 94 neonatal ICUs, and 13 pediatric ICUs. Annual nursing fee revenues per nurse were estimated based on the new nursing fee structure for each grade. Results: In general ICUs, the highest grade (grade S) and the second-highest grade (grade A) accounted for 7.3% and 41.5%, respectively, in tertiary hospitals, whereas 3.8% were grade S and 11.5% were grade A in general hospitals. In neonatal ICUs, the proportion of higher grades (S, A, and 1) was greater in general hospitals (54.3%) than in tertiary hospitals (38.6%). In pediatric ICUs, 30.8% were grade S and 61.5% were grade A. When applying the same grading criteria (i.e., beds per nurse) across both quarters, staffing levels remained unchanged in most ICUs. Nursing fees and their revenues did not increase proportionally to staffing requirements (i.e., the number of nurses required per patient). Conclusion Revisions to staffing grade and nursing fee systems are necessary to induce medical institutions to improve their ICU staffing levels.

Background: Shortage of organ donors in the Republic of Korea has become a major problem. To address this, it has been questioned whether heart transplant (HTx) allocation should be modified to reduce priority of older patients. We aimed to evaluate post-HTx outcomes according to recipient age and specific pre-HTx conditions using a nationwide prospective cohort. Methods: We analyzed clinical characteristics of 628 patients from the Korean Organ Transplant Registry who received HTx from January 2015 to December 2020. Enrolled recipients were divided into three groups according to age. We also included comorbidities including ambulatory status. Non-ambulatory status was defined as pre-HTx support with either extracorporeal membrane oxygenation, continuous renal replacement therapy, or mechanical ventilation. Results: Of the 628 patients, 195 were < 50 years, 322 were 50–64 years and 111 were ≥ 65years at transplant. Four hundred nine (65.1%) were ambulatory and 219 (34.9%) were nonambulatory. Older recipients tended to have more comorbidities, ischemic cardiomyopathy, and received older donors. Post-HTx survival was significantly lower in older recipients (P = 0.025) and recipients with non-ambulatory status (P < 0.001). However, in contrast to non-ambulatory recipients who showed significant survival differences according to the recipient’s age (P = 0.004), ambulatory recipients showed comparable outcomes (P = 0.465). Conclusion Our results do not support use of age alone as an allocation criterion. Transplant candidate age in combination with some comorbidities such as non-ambulatory status may identify patients at a sufficiently elevated risk at which suitability of HTx should be reconsidered.

Background: In 2023, we experienced an outbreak from a case of undiagnosed crusted scabies, resulting in a significant number of exposed individuals and secondary cases. In this report, we describe the outbreak control measures, the attack rate, and the risk factors for acquisition of scabies among healthcare workers (HCWs). Methods: This study was conducted in a 2,700-bed tertiary care hospital in Seoul, South Korea. The attack rate was defined both for microscopic proven cases per exposed individuals and as the sum of proven and probable cases per exposed individuals. Outbreak control measures included identifying and treating all potentially exposed individuals with or without symptoms, as well as environmental disinfection. Results: From the index, there was potential quinary transmission resulting in 63 proven cases, 142 probable cases, and a total of 1,820 exposed individuals, including 734 contacts from the index case. The attack rate from the index was 7% (50/734) based on proven cases and 19% (138/734) based on proven and probable cases. Among the 526 HCWs who received preemptive topical treatment with permethrin applied once, 21 (4%) were later diagnosed as scabies. In addition, 5 of 20 HCWs (25%) with initial proven scabies had a persistent positive microscopic exam after four permethrin treatments. In the case group, there were significantly more nurses (60% vs. 43%, P = 0.007) and nurse assistants (20% vs. 9%, P = 0.006). There were significantly more cases than controls involving direct contact with the index case (94% vs. 64%, P < 0.001). Conclusion Lowering the threshold for suspicion of crusted scabies is important, as a single missed case could lead to a large outbreak. Simultaneously applying preemptive permethrin cream to all potentially exposed individuals might have been effective in preventing further transmission. However, caution is needed because the development of scabies or persistent scabies is possible even with preemptive or therapeutic treatment.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.