This report presents radiologic changes after clinical improvement in a patient with acute interstitial nephritis (AIN). A 45-year-old female patient was referred for decreased renal function. Eight months prior, she had undergone hysterectomy and received chemotherapy. At the start of chemotherapy, her baseline creatinine level was 0.55 mg/dL, which rose to 1.46 mg/dL. Multiple imaging modalities performed when decreased renal function was observed revealed bilateral renal enlargement with increased cortical attenuation on computed tomography (CT), cortical hyperechogenicity on ultrasonography, and diffusion restriction in the renal cortices on magnetic resonance imaging. A renal biopsy was performed, and AIN was diagnosed. Follow-up laboratory tests showed that kidney function had improved to normal levels, and CT at that time showed a reduction in the size of both kidneys. Radiologic changes can serve as clues for the diagnosis of AIN. This is the first report to confirm radiological changes after the clinical improvement of AIN, thereby providing novel information about the course of AIN.

Objective: This study aimed to investigate the prevalence and characteristics of impacted teeth (ITs) in orthodontic patients at university dental hospitals in Korea. Methods: This study included 14,774 patients who visited the Department of Orthodontics at 10 university dental hospitals in Korea between 2020 and 2022 and underwent orthodontic diagnosis. The prevalence and characteristics of ITs were investigated using orthodontic diagnostic records, radiographs, and diagnostic casts. Results: The prevalence of ITs, excluding third molar impaction, in Korean orthodontic patients was 13.6% (n = 2,014).The prevalence of ITs in pediatric orthodontic patients was 24.5% (n = 1,614).Of these patients, 68.2% had one IT, 27.5% had two ITs, 24.3% had bilateral IT, and 75.7% had unilateral IT. The most frequent IT was the maxillary canine (50.1%), followed by the mandibular second molar (11.7%), and maxillary second premolar (9.6%). An abnormal eruption path (46.5%) was the most frequent etiology. Orthodontic traction after surgical exposure (70.6%) was the most frequent treatment option. Among the patients with ITs, 29.8% had other dental anomalies, such as tooth agenesis (8.7%), microdontia (8.0%), and supernumerary teeth (5.1%). Furthermore, 50.8% had complications such as cystic lesions (18.3%), transposition (17.7%), and root resorption (14.8%).Among the patients with maxillary canine impaction, 62.2% had labial maxillary canine impaction and 21.1% had palatal maxillary canine impaction. Conclusions The prevalence of ITs in Korean orthodontic patients at university dental hospitals was high, particularly in pediatric orthodontic patients.

Background: Syphilis, an infectious and chronic disease primarily transmitted through sexual contact, is caused by the spirochete bacterium Treponema pallidum. Although the introduction of penicillin has significantly reduced its incidence, syphilis continues to have a substantial impact on public health. Objective: The purpose of this study was to investigate trends in syphilis and to analyze its epidemiologic, clinical, and serologic characteristics. Methods: We retrospectively reviewed the medical records of 330 patients who tested positive for the Venereal Disease Research Laboratory (VDRL) test, including 192 patients who received a diagnosis of syphilis and who visited the Dermatology Department of Gachon University Gil Medical Center between 2000 and 2023. Statistical analyses were performed to evaluate trends in syphilis incidence and related variable factors, such as sex, age, and serological results. Results: The average age of the 192 syphilis patients was 34.18±15.81 years, with a male-to-female ratio of 1:1.2. The most prevalent age group was 20∼29 years, comprising 71 patients (37.0%). Over time, the incidence of syphilis demonstrated a decreasing trend (p＜0.001). A total of 105 patients (54.7%) were diagnosed with symptomatic syphilis, with a male-to-female ratio of 1.5:1. The proportion of symptomatic syphilis patients tended to decrease with increasing age (p＜0.05). Maculopapular syphilis was the most frequently observed presentation in secondary syphilis (36.2%). The proportion of symptomatic syphilis patients significantly increased with higher VDRL titers (p＜0.001). Conclusion The incidence of syphilis has shown a consistent decline over the past two decades. However, the relatively higher prevalence among younger age groups indicates the need for continued public health efforts.

Regorafenib is an oral multikinase inhibitor used to treat advanced solid tumors, including hepatocellular carcinoma (HCC), gastrointestinal stromal tumors, and colorectal cancer. Adverse dermatological reactions are common after regorafenib treatment. The most frequent cutaneous adverse reaction is hand-foot skin reaction (HFSR). Compared to HFSR, reports on adverse reactions on the scrotum associated with regorafenib are limited. Only a few cases of adverse reactions on the scrotum associated with HFSR have been reported. We present the case of a 55-year-old male patient with a 1-year history of scrotal dermatitis and HFSR, who had been undergoing treatment for HCC.One year after administration of oral regorafenib (160 mg/d), multiple vesicles, pustules, desquamation, and hyperkeratosis developed on both hands and feet, accompanied by scaly erythematous plaques around the scrotum.The lesions improved after two weeks of treatment with topical and systemic steroids. Herein, we report a rare case of scrotal dermatitis associated with regorafenib-induced HFSR.

Background: This study explores effective fixation methods for Pauwel type III femoral neck fractures by evaluating the biomechanical benefits of adding a screw to the Femoral Neck System (FNS). Methods: Computed tomography (CT) scans of an 82-year-old female patient with an intertrochanteric fracture were used to establish a finite element femur model with heterogeneous material properties. Finite element models of Pauwel type III fractures were created with and without an additional screw. The central and inferior trajectories of the FNS bolt were examined separately and combined with an additional screw for virtual fixation. Walking and stair-climbing loads were applied. Results: With the addition of a screw, both peak maximum and minimum principal strains consistently stayed comparable or decreased in models with both central and inferior bolt trajectories, while the volume of elements with principal strain exceeding 1% decreased by more than half. The peak von Mises stress observed in the implants ranged from 215.7 to 359.3 MPa, remaining below the titanium alloy's yield strength of 800 MPa. For normal walking, the addition of a screw to the central bolt trajectory model decreased the fracture gap by 50.6% and reduced sliding distance by 8.6%. For the inferior bolt trajectory, the gap was reduced by 57.9% and sliding distance by 25.0%.Under stair-climbing conditions, these improvements were also evident; the central trajectory model saw a halved fracture gap and a 7.9% decrease in sliding distance, while the inferior trajectory model experienced a 55.7% gap reduction and a 27.2% decrease in sliding distance. The additional screw increased the area ratio of the fracture site experiencing interfragmentary compression 34%–39%, while the additional screw alleviated peak interfragmentary compression by 12%–18% under both normal walking and stair-climbing conditions. Conclusions The addition of a screw reduced the fracture gap, sliding distance, and peak interfragmentary compression, while increasing the area ratio of interfragmentary compression under both walking and stair-climbing loads, regardless of the FNS bolt trajectory, suggesting a better mechanical environment for fracture healing.

Background: and Purpose: This clinical practice guideline provides evidence-based recommendations for treatment of dementia, focusing on cholinesterase inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonists for Alzheimer’s disease (AD) and other types of dementia. Methods: Using the Population, Intervention, Comparison, Outcomes (PICO) framework, we developed key clinical questions and conducted systematic literature reviews. A multidisciplinary panel of experts, organized by the Korean Dementia Association, evaluated randomized controlled trials and observational studies. Recommendations were graded for evidence quality and strength using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Results: Three main recommendations are presented: (1) For AD, cholinesterase inhibitors (donepezil, rivastigmine, galantamine) are strongly recommended for improving cognition and daily function based on moderate evidence; (2) Cholinesterase inhibitors are conditionally recommended for vascular dementia and Parkinson’s disease dementia, with a strong recommendation for Lewy body dementia; (3) For moderate to severe AD, NMDA receptor antagonist (memantine) is strongly recommended, demonstrating significant cognitive and functional improvements. Both drug classes showed favorable safety profiles with manageable side effects. Conclusions This guideline offers standardized, evidence-based pharmacologic recommendations for dementia management, with specific guidance on cholinesterase inhibitors and NMDA receptor antagonists. It aims to support clinical decision-making and improve patient outcomes in dementia care. Further updates will address emerging treatments, including amyloid-targeting therapies, to reflect advances in dementia management.

Purpose: Proximal gastrectomy is an alternative to total gastrectomy (TG) for early gastric cancer (EGC) treatment in the upper stomach. However, its benefits in terms of perioperative and long-term outcomes remain controversial. The aim of this study was to compare the perioperative, body compositional, nutritional, and survival outcomes of patients undergoing proximal gastrectomy with double-tract reconstruction (PG-DTR) and TG for pathological stage I gastric cancer in upper stomach. Materials and Methods: The study included 506 patients who underwent gastrectomy for pathological stage I gastric cancer in the upper stomach between 2015 and 2019. Clinicopathological, perioperative, body compositional, nutritional, and survival outcomes were compared between the PG-DTR and TG groups. Results: The PG-DTR and TG groups included 197 (38.9%) and 309 (61.1%) patients, respectively. The PG-DTR group had a lower rate of early complications (p=0.041), lower diagnosis rate of anemia and vitamin B12 deficiency (all p < 0.001), and lower replacement rate of iron and vitamin B12 compared to TG group (all p < 0.001). The PG-DTR group showed reduced incidence of sarcopenia at 6-months postoperatively, preserved higher amount of visceral fat after surgery (p=0.032 and p=0.040, respectively), and showed a higher hemoglobin level (p=0.007). Oncologic outcomes were comparable between the groups. Conclusion The PG-DTR for EGC located in the upper stomach offered advantages of fewer complications, lower incidence of anemia and vitamin B12 deficiency, less decrease in visceral fat volume, and similar survival compared to TG. Consequently, PG-DTR may be considered a superior alternative treatment option to TG.

Genetic kidney diseases are caused by mutations in specific genes that significantly affect kidney development and function. Although the underlying pathogenic genes of many kidney diseases have been identified, an understanding of their mechanisms and effective treatments remains limited. Gene editing, particularly using clustered regularly interspaced short palindromic repeats (CRISPR), has recently become a promising approach for studying genetic diseases and the CRISPR/CRISPR-associated protein 9 (CRISPR-Cas9) method has become a prominent research method. It has been shown that CRISPR-Cas9 can be targeted to knock out specific genomic sites, which enables researchers to correct gene mutations, prevent inheritance, and better understand the function of genes and the effectiveness of drugs. However, the application of CRISPR-Cas9 technology in the development of therapeutic agents against genetic kidney disease has been overlooked compared with other genetic diseases. In this paper, we provide an overview of the current research advancements in genetic kidney diseases using CRISPR technology, as well as the diverse preclinical research methods implemented, with particular emphasis on autosomal dominant polycystic kidney disease.

The application area of biportal endoscopic spine surgery (BESS) is gradually expanding. Compared with conventional fusion surgery, transforaminal interbody fusion (TLIF) using BESS (BESS-TLIF) has the advantages of less bleeding, minimal postoperative pain, and faster recovery. This technical note highlights its application in managing complex conditions such as scar tissue adhesion, altered anatomy, and implant removal, common in reoperations. The method focuses on precise dissection, endoscopic visualization, and careful tissue handling to ensure effective decompression and stabilization. Three representative cases, including reoperations for recurrent disc herniation, adjacent segment disease (ASD) following prior fusion, and ASD with nonunion of the prior fusion site requiring fusion extension, were described. All three cases exhibited clinical improvement following surgery. BESS is an effective and safe method for spinal revision surgery not only in simple decompression surgery but also in cases that required fusion surgery. As BESS is advancing, its role in complex spinal surgeries is expected to expand, potentially setting new standards in minimally invasive spine surgery.