Objective: To classify life stages for companion dogs and cats by identifying clusters in age-specific disease proportions derived from medical records, providing a data-driven foundation for health examination programs. Methods: We collected 505,667 medical records from 82 veterinary facilities in South Korea between 2020 and 2023. Diagnoses were standardized using GPT-4o and S-BioBERT. Following preprocessing, data from 27 facilities yielded 222,706 canine and 39,910 feline records for the final analysis. Principal component analysis and K-means clustering (K = 4) were applied to age-specific disease proportions to identify life stages.The 10 most highest-proportion diagnoses diseases were determined for each cluster. Results: Canine life stages were classified as ≤ 1 year, 2–5 years, 6–10 years, and 11–15+ years.Feline life stages were 1–2 years, 3–8 years, 9–12 years, and 13–15+ years. In dogs, developmental diseases were common in the youngest age group, while chronic diseases were more prevalent in older groups. In cats, oral and urinary diseases were high-ranking, conjunctivitis was most common in the early stage, and chronic diseases increased with age. Conclusions and Relevance: Age-specific diagnosis patterns support four practical life stages for dogs and cats in South Korea. These boundaries can inform evidence-based preventive examination schedules, animal health policy, and pet insurance product design.

Background: One-lung ventilation (OLV) during thoracic surgery frequently requires approximately 100% oxygen, imposing the risk of hyperoxemia. This study aimed to assess whether oxygen reserve index (ORI)-guided fraction of inspired oxygen (FiO2) adjustment can reduce the incidence of hyperoxemia in children undergoing lung resection. Methods: This prospective, randomized controlled trial enrolled children aged < 7 years scheduled for thoracoscopic lung resection. The participants were randomly assigned to either a conventional group (FiO2 adjusted based on arterial blood gas analysis [ABGA]) or an ORI group (FiO2 titrated to maintain an ORI target of 0.15). ABGA was performed 10 and 30 min after the start of OLV (T1 and T2). The primary outcome was the incidence of hyperoxemia 30 min after OLV (T2). Results: Data from 64 children (31 conventional, 33 ORI groups) were analyzed. The incidence rate of hyperoxemia at T2 was similar between the conventional and ORI groups (54.8% vs. 60.6%, P = 0.801). However, partial pressure of arterial oxygen at T1 was significantly lower in the ORI group than in the conventional group (214.6 ± 65.5 mmHg vs. 268.8 ± 92.7 mmHg, P = 0.014). The ORI group demonstrated a lower time-weighted average FiO2 during OLV (0.79 ± 0.12 vs. 0.87 ± 0.09, P = 0.004). The ORI group required more rescue interventions than the conventional group and experienced fewer episodes of hypoxia. Conclusions ORI-guided FiO2 adjustment does not significantly reduce the incidence of hyperoxemia in children undergoing OLV but reduces time-weighted FiO2 and hypoxic events.

Vaccines are highly effective, but rare or delayed adverse events following immunization (AEFIs) require post-licensure surveillance beyond clinical trials. Korea lacks a comprehensive, active, database-based framework, yet key assets exist: nationwide claims databases (National Health Insurance Service/Health Insurance Review and Assessment Service), the national immunization registry (Korea Disease Control and Prevention Agency’s Immunization Registry Information System) for National Immunization Program (NIP) and non-NIP vaccines, and increasingly standardized hospital electronic health records.We propose a federated, code to data architecture with data linkages between these data.Implementation should adopt a common data model (CDM), standardized case definitions, latency accounting, and transparent public reporting under strong privacy governance. Major challenges include multi step administrative approvals for data linkage, incomplete capture of adult non-NIP vaccinations, heterogeneous hospital data structures, and strict data protection constraints. Strategic priorities are to streamline statutory and administrative processes for public health use, mandate or enable claims-based capture of adult vaccinations, enhance CDM based interoperability, and develop secure hubs for aggregated outputs. With these measures, Korea will be well positioned to establish a scalable active surveillance system capable of detecting rare AEFIs, supporting transparent and evidence-based communication, and ensuring equitable injury compensation grounded in domestic data.

Background: Post-hemorrhagic hydrocephalus (PHH) is a frequent complication of aneurysmal subarachnoid hemorrhage (aSAH), yet the relationship between serum magnesium (Mg) level and PHH remains unclear. To our knowledge, this is the first prospective study to specifically examine the association between admission serum Mg level and PHH in aSAH patients. Methods: In this prospective, multicenter study (October 2019–October 2024), 131 patients with confirmed aSAH were enrolled from four neuro-intensive care units. Patients were stratified by admission serum Mg level as <2.2 mg/dL or ≥2.2 mg/dL. The primary outcome was PHH incidence; secondary outcomes were cerebral vasospasm (CV), delayed cerebral ischemia (DCI), and 30-day modified Rankin Scale (mRS) score. Results: Baseline characteristics were similar between groups. Serum Mg ≥2.2 mg/dL was not significantly associated with reduced vasospasm, DCI, or poor functional outcome. However, serum Mg >2.5 mg/dL correlated with lower PHH incidence in univariate analysis (odds ratio, 0.36; P=0.027) but not in multivariate analysis (P=0.136). Independent predictors of PHH were posterior circulation aneurysm, high Fisher grade, and high Hunt and Hess grade. Poor 30-day mRS was independently associated with high Fisher and Hunt and Hess grades. Conclusions Admission serum Mg level was not independently associated with PHH, although a potential protective trend was noted at higher levels (>2.5 mg/dL). These findings suggest a possible role of Mg in PHH prevention. Further prospective trials are warranted to clarify the therapeutic potential of Mg and to establish optimal monitoring and correction strategies in aSAH management.

Background/Aims: Portal vein thrombosis (PVT) frequently occurs in patients with inflammatory bowel disease (IBD), particularly when influenced by factors such as abdominal infections, IBD flare-ups, or surgical procedures. The implications of PVT range from immediate issues such as intestinal ischemia to long-term concerns including portal hypertension and its complications. However, there is a notable gap in comprehensive studies on PVT in IBD, especially with the increasing incidence of IBD in Asia. This research aimed to evaluate the clinical features and outcomes of PVT in patients with IBD at a leading hospital in South Korea. Methods: This retrospective analysis reviewed adult patients diagnosed with both IBD and PVT from 1989 to 2021 at a renowned South Korean medical center. The study focused on patient characteristics, specifics of PVT, administered treatments, and outcomes, all confirmed through enhanced CT scans. Results: A total of 78 patients met the study’s criteria. Notably, only 20.5% (16/78) were treated with oral anticoagulants; however, a vast majority (96.2%; 75/78) achieved complete radiographic resolution (CRR). When comparing patients receiving anticoagulants to those who did not, a significant preference for anticoagulant use was observed in cases where the main portal vein was affected, as opposed to just the left or right veins (p = 0.006). However, multivariable analysis indicated that neither anticoagulant use nor previous surgeries significantly impacted CRR. Conclusions Patients with IBD and PVT generally had favorable outcomes, regardless of anticoagulant use.

Purpose: Emphysematous pyelonephritis (EPN) is a life-threatening disease requiring immediate treatment. This multicenter retrospective cohort study aimed to analyze the mortality rate and risk factors associated with EPN. Materials and Methods: Between January 2011 and February 2021, 217 patients diagnosed with EPN via computed tomography who visited 14 teaching hospitals were retrospectively analyzed. Clinical data, including age, sex, comorbidities, Huang and Tseng classification, hydronephrosis, acute kidney injury, blood and urine tests, surgical interventions, percutaneous drainage, and conservative treatments, were compared between the survival and death groups. Risk factors for mortality due to EPN were analyzed using univariate and multivariate methods. Results: The mean age of survivors and deceased patients was 67.8 and 69.0 years, respectively (p=0.136). The sex distribution (male/female) was 48/146 and 8/15, respectively (p=0.298). Of the 217 patients, 23 died, resulting in a mortality rate of 10.6%. In univariate analysis, the Huang and Tseng classification (p=0.004), platelet count (p=0.005), and acute kidney injury (p=0.007) were significantly associated with mortality from EPN. In multivariate analysis, only the Huang and Tseng classification (p=0.029) was identified as a risk factor. Mortality rates according to the Huang and Tseng classification were as follows: class I (5.88%), class II (7.50%), class IIIa (14.28%), class IIIb (25.00%), and class IV (23.07%). Conclusions EPN is associated with a high mortality rate. Among various clinical factors, the Huang and Tseng classification was the most significant indicator for predicting mortality.

Background/Aims: Portal vein thrombosis (PVT) frequently occurs in patients with inflammatory bowel disease (IBD), particularly when influenced by factors such as abdominal infections, IBD flare-ups, or surgical procedures. The implications of PVT range from immediate issues such as intestinal ischemia to long-term concerns including portal hypertension and its complications. However, there is a notable gap in comprehensive studies on PVT in IBD, especially with the increasing incidence of IBD in Asia. This research aimed to evaluate the clinical features and outcomes of PVT in patients with IBD at a leading hospital in South Korea. Methods: This retrospective analysis reviewed adult patients diagnosed with both IBD and PVT from 1989 to 2021 at a renowned South Korean medical center. The study focused on patient characteristics, specifics of PVT, administered treatments, and outcomes, all confirmed through enhanced CT scans. Results: A total of 78 patients met the study’s criteria. Notably, only 20.5% (16/78) were treated with oral anticoagulants; however, a vast majority (96.2%; 75/78) achieved complete radiographic resolution (CRR). When comparing patients receiving anticoagulants to those who did not, a significant preference for anticoagulant use was observed in cases where the main portal vein was affected, as opposed to just the left or right veins (p = 0.006). However, multivariable analysis indicated that neither anticoagulant use nor previous surgeries significantly impacted CRR. Conclusions Patients with IBD and PVT generally had favorable outcomes, regardless of anticoagulant use.

Background: The effects of sugammadex, which reverses neuromuscular blockade, on emergence-related respiratory events in children remains unclear. This study compared the respiratory outcomes of sugammadex and neostigmine in pediatric tonsillectomy. Methods: Children aged 2 years to 6 years old undergoing tonsillectomy were randomly assigned to sugammadex or neostigmine groups. The primary outcome was the occurrence of respiratory adverse events, including oxygen desaturation < 95%, airway obstruction, laryngospasm, bronchospasm, severe coughing, or postoperative stridor. Secondary outcomes included bradycardia, allergic reactions, and emergence delirium. Results: The study included 172 pediatric patients (n = 86 per group). Neuromuscular blockade reversal was faster in the sugammadex group than in the neostigmine group, achieving a train-of-four ratio of 90% in a median of 1 min vs. 4 min in the neostigmine group (P < 0.001). The time to extubation was comparable between the two groups (median, 8 min; P = 0.679), as was the overall incidence of respiratory adverse events (29.0% vs. 30.2%; relative risk, 0.962; 95% confidence interval [CI], 0.607–1.524; P = 0.858). Emergence delirium occurred in 27.9% of patients overall, but the incidence was higher in the sugammadex group than in the neostigmine group (34.9% vs. 20.9%; relative risk, 1.214; 95% CI, 1.005–1.467; P = 0.044). Conclusions Sugammadex provides significantly faster neuromuscular blockade reversal compared to neostigmine but does not shorten the time to extubation or reduce the incidence of emergence-related respiratory adverse events in children undergoing tonsillectomy. Moreover, its use may be associated with an increased risk of emergence delirium.

Background: Primary cutaneous CD30+ lymphoproliferative disorders (pcCD30-LPDs) are a diseases with various clinical and prognostic characteristics. Objective: Increasing our knowledge of the clinical characteristics of pcCD30-LPDs and identifying potential prognostic variables in an Asian population. Methods: Clinicopathological features and survival data of pcCD30-LPD cases obtained from 22 hospitals in South Korea were examined. Results: A total of 413 cases of pcCD30-LPDs (lymphomatoid papulosis [LYP], n=237; primary cutaneous anaplastic large cell lymphoma [C-ALCL], n=176) were included. Ninety percent of LYP patients and roughly 50% of C-ALCL patients presented with multiple skin lesions. Both LYP and C-ALCL affected the lower limbs most frequently. Multiplicity and advanced T stage of LYP lesions were associated with a chronic course longer than 6 months. Clinical morphology with patch lesions and elevated serum lactate dehydrogenase were significantly associated with LPDs during follow-up in LYP patients. Extracutaneous involvement of C-ALCL occurred in 13.2% of patients. Lesions larger than 5 cm and increased serum lactate dehydrogenase were associated with a poor prognosis in C-ALCL. The survival of patients with C-ALCL was unaffected by the anatomical locations of skin lesions or other pathological factors. Conclusion The multiplicity or size of skin lesions was associated with a chronic course of LYP and survival among patients with C-ALCL.

Background: Comprehensive studies on the tumor burden of soft-tissue sarcoma (STS) by anatomical site are lacking in Asian populations. Objective: To investigate the anatomical distribution of STS via relative tumor density (RTD) in a Korean cohort. Methods: The RTDs of patients with STS at a single-institution from 2007–2022 were retrospectively analyzed. To describe the STS locations, the body was divided into 4 anatomical sites, and the RTD of each was calculated to the compare topographic tumor burden. Results: Fifty-nine cases in 58 individuals, 35 male (60.3%) and 23 female (39.7%), with a mean age of 56.5±20.4 were analyzed. Overall, the most frequent STS site was the lower extremity (LE, n=22, 37.3%), and the highest RTD was in the head and neck (H&N, 2.44; 95% confidence interval, 1.39–3.77). Dermatofibrosarcoma protuberans (DFSP), Kaposi’s sarcoma (KS), and angiosarcoma (AS) accounted for 76.3% of all the cases. DFSP, KS, and AS showed significantly higher RTD on the trunk (2.55, p=0.025), LE (3.88, p<0.001), and H&N (7.42, p<0.001), respectively, than elsewhere. Conclusion Each STS displays topographic variability and produces different topographic tumor burdens by body site in an Asian population.