Objective: Impact of Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) changes on the criteria for schizophrenia (SZ) has been reported to be minimal in previous studies. However, this could be different in first-episode schizophrenia spectrum disorders (FE-SSDs). We investigated what proportion of patients with FE-SSDs was diagnosed based on the sole presence of bizarre delusions (BDs) or first rank auditory hallucinations (FRAHs). Their alternative diagnosis by the DSM-5 was established and diagnostic stability over 1-year was identified. Methods: This was a retrospective review study on the medical records, case report forms for the subjects with FE-SSDs (n=404) participated in the Korea Early Psychosis Study. The two Japanese sites reviewed retrospectively only medical records of the subjects with FE-SSDs (n=103). We used three different definitions of BDs (strict, narrow, and broad) and specified subtypes of Other Specified Schizophrenia spectrum and Other psychotic disorders (OSSOs). To ensure inter-rater reliability between the hospitals, regular zoom meetings were held. Results: Forty (7.89%) subjects out of 507 were found to be diagnosed as SSDs based on the sole presence of BDs or FRAHs. All these patients met the criteria of OSSOs and were classified as having pure delusion (n=22), delusion with attenuated auditory hallucinations (AHs) (n=5), pure AHs (n=3) and AHs with attenuated delusion (n=10). The patients with first and second subtypes (n=27) were found to have BDs. The BDs fulfilled mostly strict definitions or satisfied the next broadest definition. The diagnostic stability of FE-OSSOs and its subgroups (first and second subtypes) over 1-year was substantially high (70.27% and 84% respectively). Conclusion These findings suggest that more rigorous diagnostic assessment should be performed especially to differentiate OSSOs from SZ in patients with FE-SSDs and more refined classification of the subtypes for OSSOs considered in the next DSM revision.

Purpose: : This study aimed to identify and compare the effects of home-use mechanical ventilator (MV) and facility-use mechanical ventilator on early discharge from the intensive care units (ICUs). Methods: : This retrospective study used data from the electronic medical records of 290 patients who underwent MV in the ICU of a tertiary general hospital in Seoul. Results: : Significant differences were observed in the length of ICU stay, total number of days of MV application, and length of hospital stay. The length of ICU stay was 30.00±28.14 days in the home-use MV group and 23.74±18.24 days in the facility-use MV group for facility-use (t=2.25, p=.026). The total number of days of MV application in ICU was 24.44±21.86 days in the home-use MV group and 19.35±14.25 days in the facility-use MV group (t=2.35, p=.020). The length of hospital stay was 101.88± 141.81 days in the home-use MV group and 74.24±71.38 days in the facility-use MV group (t=2.10, p=.037). The readmission rates within 72 hours of discharge from the ICU were 2.1% and 2.1%, respectively. Conclusion : A facility-use ventilator shortens the length of ICU stay and the total number of days of MV application in the ICU compared with a home-use mechanical ventilator, and it can be safely used for early discharge of patients from the ICU.

South Korea’s current vaccination policies leave a surveillance gap for non-National Immunization Program (NIP) vaccines. In this study, we proposed a sentinel surveillance approach for monitoring the safety of non-NIP vaccines. Vaccination data were collected retrospectively among patients hospitalized with pre-defined adverse events of special interest (AESI) by reviewing electronic medical records in five university hospitals. This approach incorporates expert assessment to determine the causal relationship. We confirmed that 16 patients had received non-NIP vaccines among 860 patients diagnosed with AESI.We concluded one case of preeclampsia was possibly related to tetanus-diphtheria-pertussis vaccination. We propose a multi-hospital-based, retrospective assessment system for predefined AESIs as an alternative to active vaccine safety monitoring method. These efforts are expected to enhance both the accuracy and timeliness of safety monitoring in South Korea.

Background: Graft failure (GF) is a major complication of allogeneic hematopoietic cell transplantation (allo-HCT). Secondary transplantation has been recognized as a potential curative intervention. Methods: This study aimed to investigate the characteristics and outcomes of salvage transplantation by analyzing the patients who underwent a second HCT for GF following the initial allo-HCT between 1998 and 2020. Results: Overall, 23 recipients were identified, including 14 and 9 individuals with primary and secondary GF, respectively. Nine recipients underwent a second transplant from the same donor. Familial mismatched donors predominated in the second HCT (86.9%), with reduced-intensity conditioning as the prevailing approach (60.9%). Neutrophil engraftment occurred in 17 patients (73.9%) following the second HCT at a median of 17 days (range: 9–58 days) post-transplantation. However, secondary GF subsequently occurred in 5 patients, and successful engraftment following salvage transplantation was achieved in 12 (52.2%) patients. In the entire study population, the estimated 5-year probability of overall survival (OS) and treatment-related mortality (TRM) were 30.4% and 58.5%, respectively. Among patients who achieved successful engraftment following a second transplantation, the OS and TRM rates were 41.7% and 33.3%, respectively, indicating a trend toward better OS and significantly lower TRM compared to those with GF. Notably, 17 patients died, with infection being the most common cause (n = 12), irrespective of the engraftment status. Conclusion A successful engraftment following a second allo-HCT reduced the TRM; however, the OS remained suboptimal. The effective control of infectious diseases remains crucial for patients with GF, regardless of the engraftment status following salvage transplantation.

Background: Coronavirus disease 2019 (COVID-19) is a newly emerged infectious disease that needs further clinical investigation. Characterizing the temporal pattern of combined infections in patients with COVID-19 may help clinicians understand the clinical nature of this disease and provide valuable diagnostic and therapeutic guidelines. Methods: We retrospectively analyzed COVID-19 patients isolated in four study hospitals in Korea for one year period from May 2021 to April 2022 when the delta and omicron variants were dominant. The temporal characteristics of combined infections based on specific diagnostic tests were analyzed. Results: A total of 16,967 COVID-19 patients were screened, 2,432 (14.3%) of whom underwent diagnostic microbiologic tests according to the clinical decision-making, 195 of whom had positive test results, and 0.55% (94/16,967) of whom were ultimately considered to have clinically meaningful combined infections. The median duration for the diagnosis of combined infections was 15 (interquartile range [IQR], 5–25) days after admission. The proportion of community-acquired coinfections (≤ 2 days after admission) was 11.7% (11/94), which included bacteremia (10/94, 10.63%) and tuberculosis (1/94, 1.06%). Combined infections after 2 days of admission were diagnosed at median 16 (IQR, 9–26) days, and included bacteremia (72.3%), fungemia (19.3%), cytomegalovirus (CMV) diseases (8.4%), Pneumocystis jerovecii pneumonia (PJP, 8.4%) and invasive pulmonary aspergillosis (IPA, 4.8%). Conclusion Among COVID-19 patients with risk factors for severe complications, 0.55% had laboratory-confirmed combined infections, which included community and nosocomial pathogens in addition to unusual pathogens such as CMV disease, PJP and IPA.

Background: Immunocompromised (IC) pediatric patients are at increased risk of severe acute respiratory syndrome coronavirus 2 infection, but the viral kinetics and seroimmunologic response in pediatric IC patients are not fully understood. Methods: From April to June 2022, a prospective cohort study was conducted. IC pediatric patients hospitalized for coronavirus disease 2019 (COVID-19) were enrolled. Serial saliva swab and serum specimens were subjected to reverse transcription polymerase chain reaction assays with mutation sequencing, viral culture, anti-spike-protein, anti-nucleocapsid antibody assays, plaque reduction neutralization test (PRNT) and multiplex cytokine assays. Results: Eleven IC children were evaluated. Their COVID-19 symptoms resolved promptly (median, 2.5 days; interquartile range, 2.0–4.3). Saliva swab specimens contained lower viral loads than nasopharyngeal swabs (P = 0.008). All cases were BA.2 infection, and 45.5% tested negative within 14 days by saliva swab from symptom onset. Eight (72.7%) showed a time-dependent increase in BA.2 PRNT titers, followed by rapid waning. Multiplex cytokine assays revealed that monocyte/macrophage activation and Th 1 responses were comparable to those of non-IC adults. Activation of interleukin (IL)-1Ra and IL-6 was brief, and IL-17A was suppressed. Activated interferon (IFN)-γ and IL-18/IL-1F4 signals were observed. Conclusion IC pediatric patients rapidly recovered from COVID-19 with low viral loads.Antibody response was limited, but cytokine analysis suggested an enhanced IFN-γ- and IL-18-mediated immune response without excessive activation of inflammatory cascades. To validate our observation, immune cell-based functional studies need to be conducted among IC and non-IC children.

Purpose: : This study aimed to identify and compare the effects of home-use mechanical ventilator (MV) and facility-use mechanical ventilator on early discharge from the intensive care units (ICUs). Methods: : This retrospective study used data from the electronic medical records of 290 patients who underwent MV in the ICU of a tertiary general hospital in Seoul. Results: : Significant differences were observed in the length of ICU stay, total number of days of MV application, and length of hospital stay. The length of ICU stay was 30.00±28.14 days in the home-use MV group and 23.74±18.24 days in the facility-use MV group for facility-use (t=2.25, p=.026). The total number of days of MV application in ICU was 24.44±21.86 days in the home-use MV group and 19.35±14.25 days in the facility-use MV group (t=2.35, p=.020). The length of hospital stay was 101.88± 141.81 days in the home-use MV group and 74.24±71.38 days in the facility-use MV group (t=2.10, p=.037). The readmission rates within 72 hours of discharge from the ICU were 2.1% and 2.1%, respectively. Conclusion : A facility-use ventilator shortens the length of ICU stay and the total number of days of MV application in the ICU compared with a home-use mechanical ventilator, and it can be safely used for early discharge of patients from the ICU.

Incidentally detected gallbladder polyps (GBPs) and gallbladder wall thickening (GBWT) are frequently encountered in clinical practice. However, characterizing GBPs and GBWT in asymptomatic patients can be challenging and may result in overtreatment, including unnecessary follow-ups or surgeries. The Korean Society of Abdominal Radiology (KSAR) Clinical Practice Guideline Committee has developed expert recommendations that focus on standardized imaging interpretation and follow-up strategies for both GBPs and GBWT, with support from the Korean Society of Radiology and KSAR. These guidelines, which address 24 key questions, aim to standardize the approach for the interpretation of imaging findings, reporting, imaging-based workups, and surveillance of incidentally detected GBPs and GBWT. This recommendation promotes evidence-based practice, facilitates communication between radiologists and referring physicians, and reduces unnecessary interventions.

Objective: To assess the feasibility of ultrafast brain magnetic resonance imaging (MRI) in pediatric patients. Materials and Methods: We retrospectively reviewed 194 pediatric patients aged 0 to 19 years (median 10.2 years) who underwent both ultrafast and conventional brain MRI between May 2019 and August 2020. Ultrafast MRI sequences included T1 and T2-weighted images (T1WI and T2WI), fluid-attenuated inversion recovery (FLAIR), T2*-weighted image (T2*WI), and diffusion-weighted image (DWI). Qualitative image quality and lesion evaluations were conducted on 5-point Likert scales by two blinded radiologists, with quantitative assessment of lesion count and size on T1WI, T2WI, and FLAIR sequences for each protocol. Wilcoxon signed-rank tests and intraclass correlation coefficient (ICC) analyses were used for comparison. Results: The total scan times for equivalent image contrasts were 1 minute 44 seconds for ultrafast MRI and 15 minutes 30 seconds for conventional MRI. Overall, image quality was lower in ultrafast MRI than in conventional MRI, with mean quality scores ranging from 2.0 to 4.8 for ultrafast MRI and 4.8 to 5.0 for conventional MRI across sequences (P < 0.001 for T1WI, T2WI, FLAIR, and T2*WI for both readers; P = 0.018 [reader 1] and 0.031 [reader 2] for DWI). Lesion detection rates on ultrafast MRI relative to conventional MRI were as follows: T1WI, 97.1%; T2WI, 99.6%; FLAIR, 92.9%; T2*WI, 74.1%; and DWI, 100%. The ICC (95% confidence interval) for lesion size measurements between ultrafast and conventional MRI was as follows: T1WI, 0.998 (0.996–0.999); T2WI, 0.998 (0.997–0.999); and FLAIR, 0.99 (0.985–0.994). Conclusion Ultrafast MRI significantly reduces scan time and provides acceptable results, albeit with slightly lower image quality than conventional MRI, for evaluating intracranial abnormalities in pediatric patients.

For patients with a few remaining abutment teeth, traditional removable partial dentures and implant-supported fixed prostheses are common treatment options.However, removable dentures often struggle to provide stability, especially as bone resorption occurs over time. Implant-supported fixed prostheses offer longterm stability but are costly and affected by anatomical and medical factors. A newer option is implant-assisted removable partial dentures, which use a minimal number of implants combined with a surveyed crown. This approach enhances support, retention, and stability while reducing financial and surgical burdens. It also improves the prognosis of the remaining teeth, increases patient satisfaction, and enhances masticatory function, making it a promising alternative to conventional removable dentures.