Etiology and Clinical Prediction of Community-Acquired Lower Respiratory Tract Infection in Children.

Background: Community acquired lower respiratory tract infection (LRTI) is a leading cause for hospitalization in children and important cause for antibiotic prescription. We aimed to describe the aetiology of LRTI in children and analyse factors associated with bacterial or viral infection.

Methods: Patients aged < 19 years with a diagnosis of LRTI were identified from the Observational Medical Outcomes Partnership Common Data Model Database of Seoul National University Bundang Hospital from January 2005-July 2019, and their clinical characteristics were obtained from the electronic medical records and retrospectively reviewed.

Analysis of Changes in Viral Load and Inflammatory Cytokines, as Well as the Occurrence of Secondary Infections, in SFTS Patients Treated with Specific Treatments: A Prospective Multicenter Cohort Study.

Severe fever with thrombocytopenia syndrome (SFTS) is an acute febrile illness caused by the SFTS virus (SFTSV). We conducted this study to propose a scientific evidence-based treatment that can improve prognosis through changes in viral load and inflammatory cytokines according to the specific treatment of SFTS patients. This prospective and observational study was conducted at 14 tertiary referral hospitals, which are located in SFTS endemic areas in Korea, from 1 May 2018 to 31 October 2020.

High-throughput microfluidic spheroid technology for early detection of colistin-induced nephrotoxicity with gradient-based analysis.

Colistin is essential for treating multidrug-resistant Gram-negative bacterial infections but has significant nephrotoxic side effects. Traditional approaches for studying colistin's nephrotoxicity are challenged by the rapid metabolism of its prodrug, colistin methanesulfonate and the difficulty of obtaining adequate plasma from critically ill patients. To address these challenges, we developed the Spheroid Nephrotoxicity Assessing Platform (SNAP), a microfluidic device that efficiently detects colistin-induced toxicity in renal proximal tubular epithelial cell (RPTEC) spheroids within 48 hours using just 200 μL of patient plasma.

Latent factors affecting safer injection practices that can reduce infections and how education can improve them.

Background: The incidence of healthcare-associated infections, particularly injection-related infections, can increase patient comorbidities even in countries with adequate medical resources. Although there are clear guidelines for injection practices to prevent infections, their application in clinical settings is insufficient. Therefore, the objective of this study was to identify factors affecting injection practices associated with reduced infections by conducting surveys targeting practicing healthcare providers involved in administering injections at each healthcare organization and performing data analysis.

Overcoming the age-dependent SARS-CoV-2 vaccine response through hybrid immunity: analysis of humoral and cellular immunity with mass cytometry profiling.

Background: Age-dependent immune responses to coronavirus disease 2019 (COVID-19) vaccinations and breakthrough infections (BIs) in young and middle-aged individuals are unclear.

Methods: This nationwide multicenter prospective cohort study analyzed immune responses in participants of the ChAdOx1 (ChAd)-ChAd-mRNA vaccine group using cytometry by time-of-flight, anti-spike protein antibody (Sab) and anti-nucleocapsid antibody (Nab) titers, plaque reduction neutralization tests (PRNTs), and interferon-gamma (IFN-γ) release assays at various time points.

Results: We evaluated 347 participants with an average age of 38.

The Microbiological Characteristics of Associated With Early Mortality in Patients With Bloodstream Infection.

Background: Despite rapid deaths resulting from bacteremia, the clinical impact of the microbiological characteristics of strains on early mortality (EM) is unclear. We aimed to identify the microbiological characteristics of strains associated with EM.

Methods: Clinical information and isolates from patients with bacteremia from January 2015 to December 2021 were collected.

Optimizing Treatment for Carbapenem-Resistant Complex Infections: A Review of Current Evidence.

Carbapenem-resistant complex (CRAB) poses a significant global health challenge owing to its resistance to multiple antibiotics and limited treatment options. Polymyxin-based therapies have been widely used to treat CRAB infections; however, they are associated with high mortality rates and common adverse events such as nephrotoxicity. Recent developments include numerous observational studies and randomized clinical trials investigating antibiotic combinations, repurposing existing antibiotics, and the development of novel agents.

Trends of antibiotic use at the end-of-life of cancer and non-cancer decedents: a nationwide population-based longitudinal study (2006-2018).

Objective: This study aimed to assess the actual burden of antibiotic use among end-of-life (EOL) patients in South Korea and to compare trends between cancer and non-cancer decedents.

Design: Population-based mortality follow-back study.

Setting: Data from the Korean National Health Insurance Database, covering the period from January1, 2006, to December 31, 2018, provided for research by the National Health Insurance Service (NHIS), were used.

Persistent differences in the immunogenicity of the two COVID-19 primary vaccines series, modulated by booster mRNA vaccination and breakthrough infection.

Introduction: The long-term impact of initial immunogenicity induced by different primary COVID-19 vaccine series remains unclear.

Methods: A prospective cohort study was conducted at 10 tertiary hospitals in Korea from March 2021 to September 2022. Immunogenicity assessments included anti-spike protein antibody (Sab), SARS-CoV-2-specific interferon-gamma releasing assay (IGRA), and multiplex cytokine assays for spike protein-stimulated plasma.

Incidence of Infections in Republic of Korea: A Prospective Study With Active Surveillance vs. National Data From Health Insurance Review & Assessment Service.

Background: Since the emergence of hypervirulent strains of , the incidence of infections (CDI) has increased significantly.

Methods: To assess the incidence of CDI in Korea, we conducted a prospective multicentre observational study from October 2020 to October 2021. Additionally, we calculated the incidence of CDI from mass data obtained from the Health Insurance Review and Assessment Service (HIRA) from 2008 to 2020.

False-positive results of galactomannan assays in patients administered glucose-containing solutions.

Galactomannan (GM) is a polysaccharide cell wall component released by Aspergillus spp., and an immunoenzymatic GM assay is used for the diagnosis of invasive pulmonary aspergillosis. We evaluated the cause of strong positivity for GM in patients with no typical signs of aspergillosis.

Clinical Features of Mpox Patients in Korea: A Multicenter Retrospective Study.

Background: Mpox is a viral illness with a characteristic skin rash caused by the monkeypox virus. In 2022, Mpox spread throughout the world, and an epidemic through domestic transmission started in South Korea in early 2023. This study aimed to summarize the clinical features of Mpox patients in South Korea.

bacteremia in the Republic of Korea.

In 2015, and were proposed as new species, distinct from and collectively referred to as the complex. However, no clinical reports of these new species exist in Korea. Upon the application of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for all bloodstream isolates since September 2022, was identified in one patient.

Clinical utility of quantitative immunoassays and surrogate virus neutralization tests for predicting neutralizing activity against the SARS-CoV-2 Omicron BA.1 and BA.5 variants.

Developing new antibody assays for emerging SARS-CoV-2 variants is challenging. SARS-CoV-2 surrogate virus neutralization tests (sVNT) targeting Omicron BA.1 and BA.

Tracking antigen-specific TCR clonotypes in SARS-CoV-2 infection reveals distinct severity trajectories.

Despite the importance of antigen-specific T cells in infectious disease, characterizing and tracking clonally amplified T cells during the progression of a patient's symptoms remain unclear. Here, we performed a longitudinal, in-depth single-cell multiomics analysis of samples from asymptomatic, mild, usual severe, and delayed severe patients of SARS-CoV-2 infection. Our in-depth analysis revealed that hyperactive or improper T-cell responses were more aggressive in delayed severe patients.

Coinfection With Severe Fever With Thrombocytopenia Syndrome and Scrub Typhus in Korea.

Background: Scrub typhus and severe fever with thrombocytopenia syndrome (SFTS) are the 2 most common tick-borne infectious diseases in Korea. Every year, an increasing number of cases are reported, which is a public health concern. Therefore, we aimed to investigate the prevalence of SFTS-scrub typhus coinfection in patients with SFTS.

Possibility of Decreasing Incidence of Human Immunodeficiency Virus Infection in Korea.

Background: The number of newly diagnosed cases of human immunodeficiency virus (HIV) infection in Korea, which had increased until 2019, has markedly decreased since the coronavirus disease 2019 pandemic started. This study evaluated whether the decrease is due to a reduction in the incidence of HIV infection and/or delayed diagnosis during the pandemic.

Materials And Methods: We reviewed the medical records of 587 newly diagnosed patients with HIV infection between February 2018 and January 2022 from four general hospitals, and their characteristics were compared between the pre-pandemic and pandemic periods.

Immune Response Kinetics Following a Third Heterologous BNT162b2 Booster Dose After Primary 2-Dose ChAdOx1 Vaccination in Relation to Omicron Breakthrough Infection: A Prospective Nationwide Cohort Study in South Korea.

Background: Immune responses to each vaccine must be investigated to establish effective vaccination strategies for the ongoing coronavirus disease (COVID-19) pandemic. We investigated the long-term kinetics of immune responses after heterologous booster vaccination in relation to Omicron breakthrough infection (BI).

Methods: Our study included 373 healthcare workers who received primary ChAdOx1 vaccine doses and a third BNT162b2 vaccine dose.

Isolated Tuberculous Myositis: A Systematic Review and Multicenter Cases.

Objective: To investigate the clinical features and associated underlying conditions of isolated tuberculous myositis (ITBM), a rare extrapulmonary tuberculosis (TB).

Methods: A systematic literature search and a multicenter survey were performed using a triangulation strategy. Data from the identified ITBM cases were extracted and analyzed to determine the underlying conditions, clinical presentations, treatments, and outcomes.

Antibiotic Prescription in Patients With Coronavirus Disease 2019: Analysis of National Health Insurance System Data in the Republic of Korea.

Background: Although coronavirus disease 2019 (COVID-19) is a viral infection, antibiotics are often prescribed due to concerns about accompanying bacterial infection. Therefore, we aimed to analyze the number of patients with COVID-19 who received antibiotic prescriptions, as well as factors that influenced antibiotics prescription, using the National Health Insurance System database.

Methods: We retrospectively reviewed claims data for adults aged ≥ 19 years hospitalized for COVID-19 from December 1, 2019 to December 31, 2020.