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.

Neuropathic pain markedly impairs quality of life and imposes a substantial socioeconomic burden, while available treatments often provide only partial relief and are limited by safety concerns. The Neuropathic Pain Special Interest Group of the International Association for the Study of Pain (NeuPSIG-IASP) first published pharmacologic recommendations in 2007, followed by a major update in 2015 and a new guideline in 2025. This narrative review specifically compares the 2015 and 2025 NeuPSIG-IASP guidelines, outlining key methodological changes and therapeutic shifts. The 2025 guideline is based on a larger, more rigorous meta-analysis, maintains α2δ-ligands (adds mirogabalin), serotonin-noradrenaline reuptake inhibitors, and tricyclic antidepressants as first-line drugs, downgrades tramadol into the opioid third-line group. It also introduces high-frequency motor-cortex repetitive transcranial magnetic stimulation as a weakly recommended third-line option and discusses implications for Korean clinical practice.

Background: Renal function declines with age as the kidneys become more vulnerable to inflammation and cellular senescence. This study examined gene expression changes linked to renal aging and assessed whether short-term calorie restriction (CR), a known anti-aging intervention, could reverse these alterations. Methods: Using RNA-seq data, we applied bioinformatics, systems biology, and molecular biology approaches to identify differentially expressed genes during aging and under CR. Gene Ontology and pathway analyses revealed that both aging and CR altered the expression of key senescence-associated secretory phenotype (SASP) genes, including cytokines and chemokines (Il1b, Ccl3, Ccl5, Il19, and Il24) and growth factors (Timp1 and Mmp12). Results: Renal aging is also associated with an increased expression of cell cycle arrest markers (p15INK4B (Cdkn2b), p16INK4A (Cdkn2a), and p21 (Cdkn1a)), which are suppressed by CR, suggesting a link to cellular senescence. Quantitative analysis of renal tissue samples confirmed the age-associated upregulation of these genes at the transcriptional level, and CR effectively attenuated these changes. Among these genes, we focused on the members of the interleukin 20 (IL-20) family, particularly Il19 and Il24. Furthermore, experimental induction of cellular senescence using H2O2 resulted in elevated Il19 and Il24 expression alongside other senescence markers. These findings suggest that aging and short-term CR regulate the IL-20 family expression, potentially influencing cellular senescence. Conclusion Our study suggests that Il19 and Il24 are associated with age-related renal decline and may represent hypothesis-generating candidates, highlighting potential molecular targets for future mechanistic and therapeutic investigations.

Flow cytometric lymphocyte subset analysis (FCLSA) is essential for assessing immune status across various diseases and clinical settings. We surveyed current clinical laboratory practices related to FCLSA to establish a baseline reference for future standardization in Korea. Nine university hospitals actively performing FCLSA responded to the 22-question survey, which covered seven categories of laboratory practice. These hospitals used commercial reagent antibody kits from either Beckton Dickinson Biosciences (N = 4) or Beckman Coulter Diagnostics (N = 5). Most hospitals performed daily instrument setup and scheduled maintenance every 2–6 months. Two levels of commercial quality control materials were routinely used each day. Sample and reagent antibody volumes varied across hospitals, even when the same reagent kit was used. Acquired cell counts ranged from 5 × 10 3 to 5 × 10 4 cells, with two hospitals adjusting counts based on the cell type analyzed. Most laboratories reported percentages and general opinions; some additionally reported white blood cell and lymphocyte counts, along with lymphocyte percentages. This is the first comprehensive survey on the clinical laboratory practice of FCLSA in Korea.Standardization of FCLSA should be accelerated to ensure reliable and reproducible results.

Osteoid osteoma accounts for approximately 10% of all benign bone tumors, but only approximately 4% of cases occur in the foot and ankle area. Periarticular osteoid osteoma frequently manifests with nonspecific clinical symptoms that mimic other conditions, potentially leading clinicians down a diagnostic side path and resulting in delayed or missed diagnoses compared to extra-articular osteoid osteoma. Although plain radiographs may show nonspecific findings, magnetic resonance imaging can detect bone marrow edema and surrounding soft tissue changes. Computed tomography is the most accurate modality for diagnosis. This paper reports the case of a 26-year-old female diagnosed with periarticular osteoid osteoma of the calcaneus and was treated with arthroscopic localized curettage at the author’s institution.

This case describes a male with a history of type 1 autoimmune pancreatitis (AIP) who had a concomitant branch-duct intraductal papillary mucinous neoplasm under long-term surveillance. During follow-up, new high-risk radiologic features developed within the pancreatic cyst, raising concern for malignant transformation and ultimately leading to surgical resection. However, final histopathologic examination revealed recurrent type 1 AIP rather than malignant progression of branch-duct intraductal papillary mucinous neoplasm, a finding that represents an uncommon and diagnostically challenging manifestation. This case suggests that when new imaging changes are observed during surveillance of pancreatic cystic lesions, clinicians should consider not only malignant transformation but also the possibility of recurrence or coexistence of underlying diseases such as AIP.

The global increase in obesity highlights the need for accurate tools to assess body composition and monitor treatment efficacy.Traditional metrics, including body mass index and waist circumference, offer limited precision for fat quantification. Imagingbased techniques capable of visualizing internal structures are increasingly being recognized for their ability to provide comprehensive fat assessment. This review outlines the principles, strengths, and limitations of key modalities, including dualenergy X-ray absorptiometry (DXA), CT, MRI, and bioelectrical impedance analysis (BIA). DXA is cost-effective and accessible for population-level screening, whereas CT and MRI offer higher precision, particularly for visceral fat assessment. BIA is a practical, low-cost alternative, but it is limited by variability and lack of standardization. Regulatory agencies, including the US Food and Drug Administration and the Korean Ministry of Food and Drug Safety, are increasingly supporting imaging-based endpoints in clinical trials of anti-obesity drugs because these methods capture fat mass reduction beyond total weight loss. Recent phase III trials of semaglutide and tirzepatide have underscored the utility of DXA and CT in quantifying fat loss and preserving lean mass. Selecting appropriate imaging modalities based on technical capabilities and regulatory considerations can improve the evaluation of obesity treatments and strengthen the design of anti-obesity drug trials.

Purpose: This study was performed to predict individualized treatment strategies in ruptured abdominal aortic aneurysm (rAAA) by estimating the survival benefit of endovascular aneurysm repair (EVAR) and open surgical repair (OSR) based on anatomical and physiological features using a causal inference model. Methods: This retrospective study included 45 patients with de novo rAAA who underwent EVAR or OSR between 2012 and 2024. Thirty-three variables were analyzed. The model estimated individualized treatment effects (ITE) for 30-day survival.Model interpretability was assessed using Shapley Additive Explanations (SHAP) analysis. Five-fold cross-validation, receiver operating characteristic (ROC) analysis, and calibration plots were used for model evaluation. A clinical decision tree was developed to derive simplified decision rules. Results: The mean ITE was 0.22 ± 0.42, with 33% of patients classified as OSR-benefit candidates. SHAP analysis revealed that suprarenal angle, infrarenal angle, iliac anatomy, and proximal neck characteristics strongly influenced treatment effects. However, some predictors, such as low hemoglobin and systolic blood pressure favoring OSR, conflicted with clinical intuition. ROC analysis showed an area under the curve of 1.00, but calibration suggested overfitting due to a small sample size. Treatment-matched patients had a higher 30-day mortality rate than mismatched patients, suggesting potential bias or unmeasured confounding. The decision tree identified clinically relevant features but displayed structural inconsistencies and impractical cutoff values due to the limited sample size. Conclusion The X-learner model demonstrated the feasibility of individualized treatment prediction in rAAA but suffered from overfitting and limited generalizability. Validation with larger multicenter cohorts is necessary to confirm clinical applicability.

Purpose: While progesterone receptor (PR) negativity in luminal-type breast cancer is generally associated with worse oncologic outcomes, its prognostic role in estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-positive breast cancer remains underexplored. This study aimed to evaluate the prognostic significance of PR expression in ER-positive, HER2-positive breast cancer. Methods: A retrospective analysis was conducted on patients diagnosed with ER-positive, HER2-positive breast cancer who underwent primary surgery at Korea University Guro Hospital between January 2009 and December 2019. Patients were grouped by PR expression as negative/low (Allred score, 0–6) or strongly positive (Allred score,7 or 8). Prognostic outcomes, including disease-free survival (DFS), distant recurrence-free survival (DRFS), and breast cancer-specific survival (BCSS) were analyzed. Results: A total of 223 patients were included. Patients in the negative/low PR group were older compared to the strongly positive PR group. The negative/low PR group showed significantly worse DFS (P = 0.005) and DRFS (P = 0.014) but showed no significant difference in BCSS (P = 0.153). On multivariate analysis, negative or low PR expressions were linked to inferior DFS (hazard ratio [HR], 3.10; 95% confidence interval [CI], 1.34–7.16; P = 0.008) and DRFS (HR, 9.55; 95% CI, 1.22– 74.77; P = 0.032). Conclusion In ER-positive, HER2-positive breast cancer, negative or weak PR expression was associated with inferior DFS and DRFS compared to strong PR expression. These findings highlight the potential prognostic value of PR status in this group, underscoring its relevance in guiding treatment and follow-up strategies for more individualized patient care.