Hypersensitivity reactions (HSRs) to iodinated contrast media (ICM) can range from mild cutaneous symptoms to life-threatening anaphylaxis. In patients with a history of ICM hypersensitivity, avoidance of the culprit agent is generally recommended. This case report describes a successful desensitization in a 56-year-old man with recurrent HSRs to multiple agents including ioversol, iohexol, iobitridol, and iopamidol. Intradermal testing was performed to identify potentially safe alternatives; however, all tested agents, including iohexol, ioversol, iobitridol, iopamidol, iodixanol, iomeprol, and iopromide, yielded positive results. Given the clinical necessity of transcatheter arterial chemoembolization, a 13-step rapid desensitization protocol with iodixanol was implemented. The procedure was completed without any breakthrough reactions. This case highlights desensitization as a feasible and effective strategy for patients with hypersensitivity to multiple ICM agents.

Objectives: In alignment with the World Health Organization’s goal of eliminating hepatitis C, this study assessed the current treatment status and reasons for non-treatment among patients with hepatitis C in Jeonbuk State, Republic of Korea, to inform strategies for improving care engagement. Methods: Among 311 individuals diagnosed with hepatitis C and reported through the NationalNotifiable Infectious Disease Surveillance system between January 2023 and June 2024, 208 patients were surveyed after excluding those who had died or could not be contacted.Statistical analyses included the chi-square test, the Cochran-Armitage test for trend, and logistic regression. Results: Overall, 116 participants (55.8%) reported having received antiviral therapy. Among the 92 untreated individuals, the most common reason for non-treatment was the absence of symptoms (n = 23; 25.0%), followed by the burden of drug costs (n = 21; 22.8%). Conclusion These findings highlight suboptimal treatment uptake and key barriers that may hinder progress toward hepatitis C elimination. Expanding screening and strengthening linkage-to-care strategies, while addressing financial barriers, will be essential to achievingnational elimination targets.

Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Background: Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in children, with a rising incidence of macrolide resistance. Early diagnosis is crucial for reducing the disease burden; however, current diagnostic tools have limitations.We evaluated the diagnostic accuracy of serological assays and their performance based on symptom onset in children with CAP. Methods: From September 2023 to September 2024, we prospectively enrolled children with CAP, classified as M. pneumoniae pneumonia (MPP) or non-MPP, from 16 hospitals in Korea. Serological testing included chemiluminescence immunoassay (CLIA) and ELISA for detecting IgM and IgG, along with particle agglutination (PA) for total antibody measurements. Serological responses were analyzed at different times after symptom onset (0–4, 5–9, and 10–21 days). Results: Among 472 children with CAP (362 MPP, 110 non-MPP), 138 (29.2%) underwent PA testing, and 334 (70.8%) underwent IgM testing. PA at a 1:640 cutoff showed 48.0% sensitivity and 100% specificity. CLIA and ELISA showed comparable sensitivities (69.1% vs. 69.2%) and specificities (76.9% vs. 66.7%) for IgM testing. Seropositivity increased significantly with time since symptom onset (P for trend < 0.001), reaching 97.9% for IgM, 62.5% for IgG, and 94.7% for PA at 10–21 days. Conclusions The time post-symptom onset significantly influenced the diagnostic utility of serological tests for pediatric MPP, which showed limited value during the early stage of illness. These findings emphasize the importance of symptom onset-based interpretation of serological test results and their utility in complementing PCR when optimizing MPP diagnosis in children.

Background: Lithium hydroxide (LiOH) is increasingly used in electric vehicle battery production; however, its health effects in the work environment remain underreported. This study characterizes the acute health effects on workers following accidental occupational exposure to LiOH at a Korean lithium plant in March 2024. Methods: We analyzed health effects from two LiOH exposure accidents on March 6 and 9, 2024, involving 50–100 kg powder spills. Two datasets were examined: acute symptoms from 115 workers who visited hospitals immediately after exposure, and a symptom severity survey from 474 workers conducted 2 weeks post-exposure. Workers were stratified by distance from the leak source (<10 m, 10–20 m, >20 m) and respirator use. Univariate general linear modeling was applied to analyze the relationship between symptom occurrence and both the distance from the exposure source and respirator use. Results: Among workers visiting hospitals immediately, local irritation symptoms predominated: sore throat (58.3%), cough (28.7%), and skin dermatoses (17.4%). Systemic symptoms included headache (45.2%), nausea (18.3%), chest tightness (12.2%), and dizziness (9.6%). Two-week follow-up revealed overall symptom improvement; severe cough decreased from 22.2% to 10.1%. However, despite general improvement, a significant portion of workers reported persistent respiratory issues, including cough (28.7%) and sputum production (31.0%). Symptom severity showed a significant dose-response relationship with proximity to the source (p < 0.001). While respirator use offered initial protection (p = 0.021), this effect was not statistically significant after 2 weeks. Conclusions Occupational LiOH exposure caused acute irritation and systemic symptoms, demonstrating immediate tissue damage consistent with its alkalinity and systemic toxicity upon absorption. As lithium battery production expands globally, these results emphasize the necessity for developing specific occupational exposure limits and medical surveillance guidelines for lithium compounds.

Objective: To evaluate the impact of adding CT to ultrasound (US) for nodal assessment in patients with papillary thyroid microcarcinoma (PTMC), particularly in those with US-node-negative disease. Materials and Methods: This single-center retrospective study included consecutive patients with PTMC (≤1 cm on US) who underwent both US and CT for PTMC staging between August 2016 and January 2020, and subsequently underwent surgery including neck dissection. The number of patients with clinical N1 and pathological N1 disease was assessed. The diagnostic performance of US, CT, and combined US + CT (positive if either was positive) for macroscopic lymph node metastasis (LNM) (i.e., metastatic tumor foci >2 mm) was evaluated. Cases with discordant nodal staging between US and CT were identified.The diagnostic utility of CT was also assessed in a subgroup of patients with node-negative findings on US. Results: Among 982 patients (mean age ± standard deviation, 47.3 ± 11.5 years; 774 female), pathological analysis confirmed cervical LNM in 377 patients, including macroscopic, microscopic, and size-unknown LNM in 187, 175, and 15 patients, respectively. The addition of CT to US improved sensitivity for detecting macroscopic LNM compared to US alone (68.4% [128/187] vs. 26.7% [50/187]; P < 0.001), while maintaining high specificity despite a significant decrease (90.9% [709/780] vs. 97.2% [758/780]; P < 0.001). Discordant nodal staging between US and CT regarding macroscopic LNM was observed in 149 cases (15.2% [149/982]), with 131 patients (87.9% [131/149]) being upstaged by CT. In patients with node-negative US findings, CT detected US-undetected macroscopic LNM in 78 patients (8.7% [78/895]) and exhibited a sensitivity of 56.9% (78/137) and specificity of 93.5% (709/758) for macroscopic LNM. Conclusion The integration of CT with US improved sensitivity for detecting macroscopic LNM in patients with PTMC, identifying those who would otherwise be inappropriately considered candidates for active surveillance based solely on US findings. This may assist in refining patient management.

Background: Despite advancements in laboratory animal facility management, pinworm infections remain a persistent issue in immunodeficient mouse colonies. Rapid diagnosis and treatment are crucial to mitigating potential scientific and economic consequences. Effective control requires both the administration of anthelmintic agents and rigorous environmental decontamination. However, the safety and efficacy of these treatments in genetically modified mouse models remains uncertain.Case presentation Aspiculuris tetraptera infestation was identified in multiple immunodeficient mouse models housed in a laboratory facility. Diagnosis was confirmed through fecal flotation for egg detection and necropsy for adult worm examination in the large intestines. Mice received three subcutaneous ivermectin injections at two-week intervals, coupled with environmental decontamination using ivermectin spray for four consecutive weeks. Following treatment, all colonies tested negative for A. tetraptera without any mortality. Conclusions A combination of subcutaneous ivermectin injection and environmental spray application effectively eradicated A. tetraptera infestation in immunodeficient mouse colonies. The treatment protocol led to the complete elimination of eggs and adult worms, offering a practical strategy for managing pinworm infections in genetically modified mouse models. Limitations include the small sample size, and the lack of a comprehensive evaluation of physiological and metabolic safety in immunodeficient mice. Further validation will be required to confirm the broader applicability of this approach.

Human breast milk (HBM) is an ideal nutritional source for the growth and development of infants. In addition, HBM contains hormones, growth factors, microRNAs and exosomes that perform various physiological functions. This study investigates the immunomodulatory effects of HBM-derived exosomes on myeloid cells and chondrocytes, and implications for juvenile idiopathic arthritis. HBM-derived exosomes were isolated and characterized using nanoparticle track analyzer and Western blotting. The HBM-derived exosomes treatment decreased the expression of inflammatory mediators and proinflammatory cytokines in mouse peritoneal macrophages upon lipopolysaccharide stimulation. Flow cytometry analysis of bone marrow-derived macrophages indicated that exosomes promoted M2 polarization, as evidenced by a decrease in cells expressing CD80 (M1 marker) and a concurrent increase in cells expressing M2 marker CD206. In addition, exosome treatment attenuated the mitogen-activated protein kinase signaling pathway by reducing the phosphorylation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38 mitogen-activated protein kinase, and IκB-α, thereby reducing the expression of inducible nitric oxide synthase, cyclooxygenase-2, metalloprotease (MMP)-1, MMP-3, and MMP-13 in SW1353 chondrocytes following IL-1β stimulation. These findings suggest that HBM-derived exosomes promote macrophage polarization toward an anti-inflammatory M2 phenotype and exert significant immunomodulatory effects.

Autophagy is a conserved catabolic process that degrades proteins and damaged organelles to maintain cellular homeostasis, and its role in cancer depends on stage and context. Farnesyl-diphosphate farnesyltransferase 1 (FDFT1) is an essential enzyme in the sterol branch of the mevalonate pathway, but its functions in hepatocellular carcinoma (HCC) and in the regulation of autophagy remain poorly understood. In this study, we show that FDFT1 acts as a negative regulator of autophagy in HCC cells. Loss of FDFT1 led to increased autophagosome formation and fusion with lysosomes, whereas its overexpression suppressed both basal and induced autophagy. These changes were associated with AMPK–ULK1 signaling, suggesting that FDFT1 influences a central pathway controlling autophagy. Our findings connect cholesterol metabolism with autophagy regulation and tumor growth, highlighting FDFT1 as a potential prognostic marker and therapeutic target in liver cancer.

Purpose: This study aimed to report the real-world outcomes of intravesical gemcitabine for bacillus Calmette–Guérin (BCG)–unresponsive, high-risk, non–muscle-invasive bladder cancer (HR-NMIBC) in Korean patients who were unable or unwilling to undergo radical cystectomy (RC). Materials and Methods: This retrospective study included 131 patients (median age, 69 years; 88.5% men) treated with intravesical gemcitabine for BCG-unresponsive HR-NMIBC at nine centers between May 2019 and April 2022. The primary endpoint was 1-year recurrence-free survival (RFS). The secondary endpoints included factors influencing RFS, progression-free survival (PFS), cystectomy- free survival, cancer-specific survival (CSS), overall survival (OS), and safety. Survival analysis was performed using the Kaplan-Meier method, and risk factors for recurrence were assessed using Cox regression models. Results: Patients were followed up for a median duration of 25 months, with carcinoma in situ (CIS) in 41.9% of the patients. The 1-year and 2-year RFS rates were 68% and 42%, while the 1-year and 2-year PFS rates were 87% and 77%, respectively. No significant factors influencing RFS were identified. Seventeen patients underwent RC during a median follow-up of 16 months, with the condition in three patients progressing to muscle-invasive disease on final pathological analysis. The 2-year CSS and OS rates were 98% and 97%, respectively. Intravesical gemcitabine was well-tolerated, with only seven patients (5.3%) unable to complete the full induction course. Conclusion Our research highlights the potential of intravesical gemcitabine as a viable bladder-sparing treatment option for BCG-unresponsive HR-NMIBC, providing real-world evidence on its safety, efficacy, and tolerability.