Purpose: Asthma is characterized by chronic type 2/eosinophilic inflammation in the airway mucosa. This study aimed to explore the clinical value of 2 cutoffs of blood eosinophil counts (≥ 300/μL and ≥ 150/μL) in eosinophilic asthma, with relation to eosinophilderived neurotoxin (EDN), a surrogate marker of eosinophilic activity. Methods: To compare clinical features and eosinophil-related mediators according to 2 cutoffs of peripheral blood eosinophil counts (≥ 300/μL and ≥ 150/μL), 137 adult asthmatics who had maintained antiasthmatic medications, including inhaled corticosteroid and long-acting beta 2 agonist, without biologics, were enrolled. EDN levels in serum, urine and sputum were measured by enzymelinked immunosorbent assay. Results: Patients with asthma and higher blood eosinophil counts ( ≥ 300/μL) had a higher prevalence of severe asthma, chronic rhinosinusitis, partly controlled/uncontrolled status, and higher levels of sputum eosinophils and EDN in serum/sputum than those with lower blood eosinophil counts (< 300/μL). When compared between patients with asthma having higher blood eosinophils ( ≥ 150/μL) and those with lower eosinophils ( < 150/μL), there were no differences in symptom severity, control status or lung function parameters. Conclusion These findings suggest that blood eosinophil count ≥ 300/μL may identify asthma patients at higher risk for severity and heightened eosinophil activity, supporting its utility as a biomarker in a real clinical setting.

Background/Aims: This study investigated the clinical efficacy of low-dose mepolizumab (100 mg) in controlling severe eosinophilic asthma, aiming to induce eosinophilic granulomatosis with polyangiitis (EGPA) remission and reduce systemic steroid usage. Additionally, we constructed a basic frame for our longitudinal EGPA cohort by collecting serial blood samples before, during, and after mepolizumab treatment in EGPA patients. Methods: We conducted a 2-year prospective observational cohort study in patients with uncontrolled severe eosinophilic asthma and refractory EGPA who used systemic steroids (≥ 7.5 mg/day of prednisolone) or other immunosuppressant drugs for at least 6 months. All patients were treated with 100 mg of mepolizumab every 4 weeks for 1 year to control severe eosinophilic asthma and then were followed for an additional 1 year to monitor their disease course. We analyzed total systemic steroid use and EGPA remission/relapse during the study period. Results: Three EGPA patients were included in this study and completed 16 study visits over a 2-year period. After 1 year of treatment with mepolizumab (100 mg monthly), all 3 patients were able to reduce their maintenance dose of systemic steroids, with 2 patients completely discontinuing use. These 2 patients achieved EGPA remission during mepolizumab treatment, and their remission status remained stable for 1 year after they stopped receiving the medication. Conclusions Low-dose mepolizumab treatment demonstrated clinical efficacy in reducing the maintenance dose of systemic steroids required for severe refractory EGPA. While not all patients achieved EGPA remission with low-dose mepolizumab, some did, and their remission persisted even after treatment discontinuation.

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.

Background: Retinitis pigmentosa (RP) comprises a heterogeneous group of inherited retinal dystrophies. The genetic landscape of RP has been characterized; however, knowledge gaps regarding age-specific genetic variation trends in Korean patients remain. We comprehensively characterized the age-stratified genetic landscape of RP in Korean patients, with a focus on identifying novel mutational trends and clinically actionable insights. Methods: We performed targeted next-generation sequencing of 199 genes associated with RP and related disorders in a cohort of 403 unrelated patients clinically diagnosed as having RP. We analyzed the inheritance patterns, variation spectrum, and prevalence of pathogenic variants, stratifying the results by age, and conducted copy number variation (CNV) analysis. Results: A genetic diagnosis was achieved for 193 of the 403 patients (48%). The diagnostic yield was highest in patients diagnosed before 20 yrs of age (60%), with lower yields in older age groups. Although USH2A and EYS, the most common causative genes in autosomal recessive inheritance, were frequently identified, RPGR pathogenic variants accounted for a significantly larger proportion of genetically solved cases diagnosed before the age of 20 yrs (27%–28%) than in those with later-onset disease (9%–15%). CNVs were identified in 4% of genetically solved cases. Conclusions The results underscore distinct, age-related genetic contributions to RP in Korean patients, with RPGR variants demonstrating relevance in early-onset disease, and provide diagnostic insights to improve current practices. These findings can aid in prioritizing gene therapy targets and refining screening strategies.

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.

Purpose: Psychiatric conditions are common in children and adolescents with diabetes and can hinder disease management. In this study, we examined whether mental health status at diagnosis predicts glycemic control at 1 year. Methods: We included 57 patients aged 6–18 years diagnosed with type 1 or type 2 diabetes between 2019 and 2023 at Seoul National University Bundang Hospital. Mental health was assessed within 3 months of diagnosis using the Eating Disorder Inventory-2, Children’s Depression Inventory, and Child Behavior Checklist (CBCL) for ages 6–18. Poor glycemic control was defined as glycated hemoglobin >6.5% at 1 year. Associations between screening results and glycemic control were analyzed using Fisher exact test and multivariate logistic regression. Results: Of the 57 patients, 32 (56.1%) had type 1 diabetes, and the mean age at diagnosis was 12.9±3.1 years; 31 (54.4%) were male. Poor glycemic control at 1 year was observed in 16 patients (28.1%). Although individual subscale positivity was not significantly associated with glycemic control, borderline somatic complaints on the CBCL were significantly associated with poor control (p=0.022). In multivariate analysis, having 2 or more positive CBCL subscales showed a trend toward association with poor glycemic control (adjusted odds ratio=21.47, p=0.054). Conclusion Early psychological screening, especially for somatic symptoms or multiple psychological problems, may help identify those at risk for poor glycemic control in pediatric diabetes. These findings underscore the importance of early detection and intervention in optimizing diabetes management.

Purpose: This study aimed to evaluate the effects of a practitioner-led empowerment program on self-sufficiency motivation, self-esteem, and self-efficacy among low-income service recipients at self-sufficiency centers. Methods: A quasi-experimental repeated-measures design was used. Participants were recipients of social services from 11 local self-sufficiency centers in Gyeonggi-do, South Korea. In total, 100 participants were recruited, with 51 assigned to the experimental group and 49 assigned to the control group. The experimental group received an eight-session program delivered by center practitioners who had been trained by mental health nurses, whereas the control group received usual services. Self-sufficiency motivation, self-esteem, and self-efficacy were assessed at three time points: baseline (pretest: T0), immediately after the intervention (post-test: T1), and 4 weeks after the intervention (follow-up: T2). Results: Using generalized estimating equations, participants in the experimental group showed significantly greater improvements than those in the control group at both T1 and T2 in self-sufficiency motivation (T1: B=1.61, p=.030; T2: B=2.88, p<.001), self-esteem (T1: B=2.77, p<.001; T2: B=2.78, p<.001), and self-efficacy (T1: B=3.95, p=.004; T2: B=4.19, p<.001). Conclusion The practitioner-led program is associated with significant short-term improvements in psychosocial determinants of self-sufficiency among low-income service recipients. These findings may inform the development of community nursing interventions that support the psychosocial foundations of independent living in this population and provide a basis for training programs designed to strengthen the capacity of practitioners at local self-sufficiency centers (Clinical Research Information Service of Korea registration number: KCT0010027; registration date: December 12, 2024).

Background/Aims: Potassium-competitive acid blockers (P-CABs) have emerged as promising alternatives to proton pump inhibitors (PPIs) to treat erosive esophagitis (EE). This study aims to compare the efficacy and safety of P-CABs and PPIs in patients with mild to severe EE stratified by treatment phase. Methods: A systematic literature search was conducted using PubMed, MEDLINE, and the Cochrane Central Register of Controlled Trials. Randomized controlled trials comparing the efficacy of P-CABs and PPIs for EE were included. The pooled risk ratios (RRs) and risk differences with 95% confidence intervals (CIs) were calculated. A frequentist network meta-analysis was performed, and treatment ranking was assessed using P-scores. Results: Nineteen studies evaluating 5 P-CABs (vonoprazan, tegoprazan, keverprazan, fexuprazan, and zastaprazan) and 2 PPIs (lansoprazole and esomeprazole) were included. P-CABs demonstrated superior efficacy in healing EE during the initial phase, particularly in patients with severe EE (RR = 1.10; 95% CI, 1.00-1.20) and were also associated with a lower EE recurrence risk during maintenance treatment (RR = 0.59; 95% CI, 0.41-0.85). The efficacy was notably greater in patients with higher EE severity and among cytochrome P450 2C19 extensive metabolizers. The safety profiles of the P-CABs and PPIs were comparable. Vonoprazan consistently ranked the highest for both initial treatment (P-score = 0.68) and maintenance (P-score = 0.94). Conclusions P-CABs, especially vonoprazan, showed superior efficacy compared to PPIs in both the initial and maintenance treatment of EE. These findings support the use of P-CABs as a potent and reliable first-line option for EE management, particularly in high-risk populations, with acceptable safety outcomes.

Gastroesophageal reflux disease (GERD) is a chronic and relapsing gastrointestinal disorder characterized by the reflux of gastric contents into the esophagus, leading to troublesome symptoms and/or complications. Since the publication of the 2020 Seoul Consensus on GERD, significant new evidence has emerged, particularly regarding acid-suppressive therapies and diagnostic approaches. This 2025 focused update aims to refine GERD management strategies by incorporating the latest evidence on acid suppressive therapies and regional considerations in Asian populations. This study builds on the 2020 Seoul Consensus by integrating systematic reviews, meta-analyses, and expert consensuses to offer updated recommendations for the definition and medical treatment of GERD. These guidelines incorporate recent advances in acid-suppressive therapies, particularly potassium-competitive acid blockers, and adopt updated diagnostic frameworks in accordance with the Lyon Consensus 2.0. Key clinical questions were identified and structured using the following format: Population, Intervention, Comparator, Outcome. The resulting recommendations address the initial treatment, long-term maintenance strategies, and role of personalized therapy based on disease severity, such as the grade of reflux esophagitis. Six key statements are presented: updated definition and classification of GERD (Statement 1); initial and long-term treatment strategies tailored to GERD phenotypes, such as non-erosive reflux disease, mild erosive esophagitis, and severe erosive esophagitis (Statements 2-5); and dose optimization strategies for long-term safety (Statement 6). These guidelines aim to support gastroenterologists and general healthcare providers in making individualized evidence-based decisions for GERD management.

Background: Handgrip strength (HGS) is an indicator of late-life health, associated with disability, cardiovascular and all-cause mortality. While exercise helps maintain HGS, diabetes may reduce its benefits. This study investigated the association between exercise and low HGS (LHGS) stratified by diabetes status and sex. Methods: Data from 16,443 participants in the 2017–2019 Korea National Health and Nutrition Examination Survey were analyzed. HGS was measured using a digital dynamometer. Exercise type and frequency were assessed by questionnaire. Three-way and twoway interaction terms were analyzed for exercise, sex and diabetes. Results: Aerobic exercise, resistance exercise, and diabetes were significantly associated with LHGS (P<0.05). A significant interaction between diabetes and aerobic exercise was observed in females (odds ratio [OR] of LHGS=1.704, 95% confidence interval= 1.073–2.707). Among males, both exercise types were associated with lower odds of LHGS regardless of diabetes status, except for aerobic exercise in non-diabetic males. Among males, the ORs of LHGS for aerobic and resistance exercise were 0.479 (0.278– 0.827) and 0.317 (0.165–0.611) with diabetes, 0.757 (0.554–1.035) and 0.536 (0.360–0.798) without diabetes. Among females, the ORs of LHGS for aerobic exercise and resistance exercise were 1.109 (0.716–1.719) and 0.529 (0.224–1.249) with diabetes, 0.676 (0.539–0.848) and 0.795 (0.564–1.121) without diabetes. Conclusions The modifying effect of diabetes on the relationship between exercise and grip strength was observed in females but not in males. Females with diabetes may require tailored exercise guideline to prevent LHGS.