Childhood asthma is a common chronic respiratory disease with a heterogeneous course, including remission, persistence, and relapse. Although about 50% of the affected children achieve clinical remission, many relapse; furthermore, airway inflammation or lung function impairment may persist even during remission. By synthesizing findings from cohort studies conducted in the United Kingdom, New Zealand, Australia, the United States, Canada, Sweden, The Netherlands, Denmark, Turkey, and Iran, we reviewed the long-term course of childhood asthma and prognostic factors influencing remission. Clinical remission rates ranged from 25% to 65% across cohorts, whereas complete remission defined as normal lung function with the absence of bronchial hyperresponsiveness was limited to 15%–30%. Even among the patients in clinical remission, many continued to show reduced lung function, bronchial hyperresponsiveness, and airway inflammation. Prognostic factors for remission failure and persistence included low forced expiratory volume in 1 second/forced vital capacity ratio, bronchial hyperresponsiveness, female sex, early onset, disease severity, atopy, parental history of asthma, and high healthcare utilization shortly after diagnosis. In contrast, children with normal lung function, normal eosinophil count and normal airway responsiveness had higher than 80% likelihood of remission in adulthood. Earlylife bronchiolitis, severe asthma, sensitization to house dust mite, Alternaria, and furred animals, elevated fractional exhaled nitric oxide levels and peripheral eosinophilia were associated with persistent or relapsing asthma. In addition, non-White populations showed lower remission rates compared with White populations. Therefore, symptom control, preservation of lung function, and prevention of exacerbations remain the most pragmatic treatment goals, while early intervention strategies based on prognostic factors may help reduce persistence and relapse.

Janus kinase (JAK) inhibitors are an important treatment option for ulcerative colitis, providing rapid onset of action, oral administration, and efficacy even after biologic failure. The 3 approved agents—tofacitinib, filgotinib, and upadacitinib—differ in JAK isoform selectivity, leading to clinically meaningful differences in efficacy and safety. Evidence from network meta-analyses, clinical trials, and real-world studies consistently shows that upadacitinib provides the highest efficacy for induction and maintenance of remission, whereas filgotinib demonstrates the most favorable safety profile. The strong efficacy of upadacitinib and tofacitinib is particularly relevant in patients with severe disease, including acute severe ulcerative colitis, and upadacitinib maintains high efficacy regardless of prior advanced therapy exposure. JAK inhibitors also benefit extraintestinal manifestations. Although risks such as herpes zoster, serious infection, thromboembolism, and major cardiovascular events differ among agents, long-term data suggest generally acceptable safety when used appropriately. Intraclass JAK-to-JAK cycling is feasible, with about half of patients achieving steroid-free clinical remission in retrospective cohorts. Based on mechanistic, clinical, and real-world evidence, filgotinib may be a first-line option for patients with lower disease activity or when safety is a priority, whereas upadacitinib or tofacitinib may be preferred in higher disease activity. Strategically selecting agents may improve durability and outcomes.

Purpose: Eosinophils and total immunoglobulin (IgE) have served as a histologic hallmark of allergic conditions. Many investigators have used total eosinophil count (TEC) and total IgE for evaluating allergic diseases. We examined differences in TEC and total IgE in allergic diseases and whether it differs according to sensitization. Methods: In this retrospective study, we enrolled 551 patients who visited Uijeongbu St. Mary’s Hospital from January 1, 2009 through December 31, 2012 for allergic diseases. We included patients with a diagnosis of atopic dermatitis (AD), allergic rhinitis (AR), asthma (AS), or urticaria (UC). We compared the TEC and total IgE level according to sensitization patterns. Results: There were 235 cases of AD, 179 cases of AS, 112 cases of AR, and 82 cases of UC. Regarding sensitization, 106 were not sensitized to any allergens, 206 were sensitized to inhalants, 109 were sensitized to food allergens, and 49 were sensitized to both food and inhalant allergens. TEC was significantly higher in the AD and AR group than in the UC group. TEC was significantly higher in those sensitized to both inhalant and food than those not sensitized. The total IgE levels were significantly higher in those sensitized to both inhalant and food than those not sensitized or sensitized to food. Total IgE levels were significantly higher in those sensitized to inhalant than those not sensitized or sensitized to food. Conclusion Eosinophils appear to play differential roles in the expression of different types of allergic diseases. Total IgE level may play a significant role in sensitization.

Allergen immunotherapy (AIT) has been used for over a century and has been demonstrated to be effective in treating patients with various allergic diseases. AIT allergens can be administered through various routes, including subcutaneous, sublingual, intralymphatic, oral, or epicutaneous routes. Sublingual immunotherapy (SLIT) has recently gained clinical interest, and it is considered an alternative treatment for allergic rhinitis (AR) and asthma. This review provides an overview of the current evidence-based studies that address the use of SLIT for treating AR, including (1) mechanisms of action, (2) appropriate patient selection for SLIT, (3) the current available SLIT products in Korea, and (4) updated information on its efficacy and safety. Finally, this guideline aims to provide the clinician with practical considerations for SLIT.

Allergen immunotherapy (AIT) is a causative treatment of allergic diseases in which allergen extracts are regularly administered in a gradually escalated doses, leading to immune tolerance and consequent alleviation of allergic diseases. The need for uniform practice guidelines in AIT is continuously growing as the number of potential candidates for AIT increases and new therapeutic approaches are tried. This updated version of the Korean Academy of Asthma Allergy and Clinical Immunology recommendations for AIT, published in 2010, proposes an expert opinion by specialists in allergy, pediatrics, and otorhinolaryngology. This guideline deals with the basic knowledge of AIT, including mechanisms, clinical efficacy, allergen standardization, important allergens in Korea, and special consideration in pediatrics. The article also covers the methodological aspects of AIT, including patient selection, allergen selection, schedule and doses, follow-up care, efficacy measurements, and management of adverse reactions. Although this guideline suggests the optimal dosing schedule, an individualized approach and modifications are recommended considering the situation for each patient and clinic.

Background/Aims: The programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has not been fully evaluated in inflammatory bowel disease. We evaluated PD-1/PD-L1 levels in patients with ulcerative colitis (UC) and their significance in tonsil-derived mesenchymal stem cells (TMSCs) treatment. Methods: Using acute and chronic murine colitis model, we measured the PD-1 and PD-L1 levels in inflamed colonic tissues pre- and post-treatment with TMSCs. We also measured PD-1 and PD-L1 levels in colonic tissues from UC patients, compared to normal controls. Results: In the analysis using human colonic tissues, a significant increase in the levels of PD-1 and PD-L1 was observed in the colonic mucosa of patients with UC compared with normal controls (p < 0.001 and p = 0.005, respectively). When comparing the maximal disease extent, PD-L1 levels were highest in patients with proctitis (38.5 ± 46.7), followed by left-side colitis (17.5 ± 23.1) and extensive colitis (5.2 ± 8.2) (p < 0.001). In the chronic colitis model, the level of PD-L1 was decreased (p = 0.040) and the level of PD-1 increased more than in normal controls (p = 0.047). After treatment with TMSC, significant improvements were observed in body weight, disease activity index, and colon length recovery. Additionally, the levels of PD-1 and PD-L1 were recovered; PD-L1 significantly increased (p = 0.031), while the level of PD-1 decreased (p = 0.310). Conclusions The altered expression of PD-1 and PD-L1 in colonic mucosa may be a possible mechanism of UC, and T-MSC-derived PD-L1 could help suppress colitis.

Background: In patients undergoing percutaneous coronary intervention (PCI) in the SMART-CHOICE trial, P2Y12 inhibitor monotherapy after three months of dual antiplatelet therapy (DAPT) achieved clinical outcomes comparable to those of 12 months of DAPT.Nonetheless, the effects of sex on these outcomes remain unknown. Methods: This open-label, non-inferiority, randomized study, conducted in 33 hospitals in South Korea, included 2,993 patients undergoing PCI with drug-eluting stents. Patients were randomly assigned to receive DAPT (aspirin plus a P2Y12 inhibitor) for three months then P2Y12 inhibitor alone for nine months, or DAPT for the entire 12 months. The primary endpoints were major adverse cardiac and cerebrovascular events (a composite of all-cause death, myocardial infarction, or stroke) 12 months after the index procedure. The bleeding endpoints were Bleeding Academic Research Consortium (BARC) bleeding types 2 to 5. Results: Of the patients, 795 (26.6%) were women, who were older and had a higher prevalence of hypertension, diabetes, and dyslipidemia than men. The sexes exhibited comparable primary endpoints (adjusted hazard ratio [HR], 0.93; 95% confidence interval [CI], 0.55–1.55; P = 0.770) and bleeding endpoints (adjusted HR, 1.07; 95% CI, 0.63–1.81; P = 0.811). P2Y12 inhibitor monotherapy vs DAPT was associated with lower risk of BARC type 2 to 5 bleeding in women (adjusted HR, 0.40; 95% CI, 0.16–0.98; P = 0.045) but the difference was not statistically significant when using the Bonferroni correction. The primary endpoints were similar between treatment groups in both sexes. Conclusion In both sexes undergoing PCI, P2Y12 inhibitor monotherapy after three months of DAPT achieved similar risks of the primary endpoints and the bleeding events compared with prolonged DAPT. Therefore, the benefits of early aspirin withdrawal with ongoing P2Y12 inhibitors may be comparable in women and men.

Objective: Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one’s physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia. Methods: Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology. Results: Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended. Conclusion This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.

Background: Transient receptor potential canonical (TRPC) channels are non-selective cationic channels with perme‑ ability to ­Ca2+ and ­Na+ . Despite their importance, there are currently few studies on TRPC in the periodontal ligament (PDL) and bone cells in the dental field. To provide biological information regarding TRPC in PDL cells and periodontal tissue, we evaluated TRPC channels expression in the osteoblast differentiation of PDL cells and periodontitis-induced tissue. Human PDL cells were cultured in osteogenic differentiation media for 28 days, and the expression of Runx2, osteocalcin (OCN), and TRPC1, 3, 4, and 6 was evaluated by real-time PCR. In ligature-induced periodontitis mice, the alveolar bone and osteoid areas, the osteoclast number, and the expression of Runx2, OCN, TRPC3, and TRPC6 was evaluated by H&E staining, TRAP staining, and immunohistochemistry, respectively. Results: In the PDL cell differentiation group, TRPC6 expression peaked on day 7 and TRPC3 expression generally increased during differentiation. During the 28 days of periodontitis progression, alveolar bone loss and osteoclast numbers increased compared to the control group during the experimental period and the osteoid area increased from day 14. TRPC6 expression in the periodontitis group increased in the PDL area and in the osteoblasts compared to the control group, whereas TRPC3 expression increased only in the PDL area on days 7 and 28. Conclusions These results indicate changes of TRPC3 and TRPC6 expression in PDL cells that were differentiating into osteoblasts and in periodontitis-induced tissue, suggesting the need for research on the role of TRPC in osteo‑ blast differentiation or periodontitis progression.

Background/Aims: Chronic hepatitis C is a major risk factor for liver cirrhosis, hepatocellular carcinoma, and hepatic failure. Although traditional practices, including acupuncture, tend to increase the risk of HCV infection, the association remains controversial. Therefore, the current meta-analytical study was undertaken to evaluate the risks of acupuncture and hepatitis C transmission. Methods: Two researchers independently screened studies from the databases encompassing the period from inception to May 12, 2022. Baseline demographics, HCV transmission OR, and 95% CIs were extracted, pooled, and analyzed using random-effect models.Subgroup analyses utilizing study design and ethnicity were performed. Heterogeneity and publication bias were analyzed using the Higgins I2 test and funnel plots, respectively. Results: In all, 28 studies with 194,826 participants (178,583 controls [91.7%] vs. 16,243 acupuncture users [8.3%]) were included in the final analysis. The pooled analysis showed that acupuncture users had a significantly higher HCV transmission rate than controls with heterogeneity (OR, 1.84 [1.46–2.32]; p<0.001; I2 =80%). In the subgroup analysis, both cross-sectional case-control (n=14; OR, 1.96 [1.47–2.61]; p<0.001; I2 =88%) and cross-sectional studies (n=12; OR, 1.85 [1.32–2.61]; p<0.001; I2 =0%) showed significantly higher HCV infection rates in the acupuncture group than in the control group. Both Asian and non-Asian acupuncture users showed a higher HCV transmission risk than the controls (all Ps <0.001). No significant publication bias was observed. Conclusions Our findings indicate that acupuncture increases the risk of HCV transmission. Due to HCV's contagiousness, unsafe medical and social practices (including acupuncture) should be performed with caution.