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.

Background and Objectives: The medications preferred by patients for allergic rhinitis and their usage remain unclear. This study investigated treatment-seeking behaviors in patients with allergic rhinitis, including medical treatments, environmental controls, and surgical treatments. Methods: In this study, a cross-sectional survey was conducted by internal medicine, pediatric, or otorhinolaryngology physicians at university hospitals from January 2022 to April 2022. A questionnaire was administered to patients with confirmed allergic rhinitis to collect information regarding medical treatments (prescription and over-the-counter medication use patterns, comorbid asthma, and allergen-specific immunotherapy), environmental controls (usage of air purifiers and pet avoidance), and experiences with surgical treatments. Results: We included 51 patients with allergic rhinitis with a mean age of 31.6±16.0 years. Among them, 47 (92.2%) and 6 (11.8%) patients had pollen allergies and asthma, respectively. Furthermore, 41 (80.4%) patients took prescribed medicines, while 39 (76.5%) patients only used the medication when experiencing symptoms. Thirty patients (58.8%) reported concurrent use of intranasal sprays and oral medications. Thirty-three patients (64.7%) reported awareness of immunotherapy, and there were no preferential differences between subcutaneous (52%) and sublingual immunotherapy (48%). Of the 36 patients (70.6%) who reported using an air purifier, 38.9% considered it helpful in preventing allergic rhinitis symptoms. Fourteen patients (27.5%) currently or previously had a companion animal, with half experiencing worsening of symptoms. Twelve patients had received surgical treatment and reported high satisfaction levels (41.6%, very satisfied; 41.6%, satisfied). Conclusion Patients with allergic rhinitis showed similar preferences for oral and spray medications. They also showed satisfaction with surgical treatments and an interest in the environmental management of allergic rhinitis.

Atopic dermatitis (AD) is the most prevalent inflammatory skin condition, with approximately 80% of cases originating in childhood and some emerging in adulthood. In South Korea, the estimated prevalence of AD ranges between 10% and 20% in children and 1% and 3% in adults. Severe/recalcitrant AD manifests as a chronic, relapsing skin disorder, persisting with uncontrolled symptoms even after topical steroid treatment. Corticosteroids and systemic immunosuppression, conventionally the standard care for difficult-to-treat diseases, cause numerous undesirable side effects. When AD persists despite topical steroid application, systemic therapies like cyclosporine or systemic steroids become the second treatment strategy. The desire for targeted treatments, along with an enhanced understanding of AD’s pathophysiology, has spurred novel therapeutic development. Recent advances introduce novel systemic options, such as biological agents and small-molecule therapy, tailored to treat severe or recalcitrant AD. Notably, dupilumab, a monoclonal antibody inhibiting interleukin 4 and 13, marked a transformative breakthrough upon gaining approval from the U.S. Food and Drug Administration (FDA) in 2017, leading to a paradigm shift in the systemic treatment of AD. Furthermore, both dupilumab and Janus kinase inhibitors, including baricitinib, abrocitinib, and tofacitinib, now approved by the Korean FDA, have established their applicability in clinical practice. These innovative therapeutic agents have demonstrated favorable clinical outcomes, effectively addressing moderate to severe AD with fewer side reactions than those associated with previous systemic immunosuppressants. This review summarizes the latest advancements and evidence regarding systemic treatments for AD, including newly approved drugs in Korea.

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 and Objectives: The medications preferred by patients for allergic rhinitis and their usage remain unclear. This study investigated treatment-seeking behaviors in patients with allergic rhinitis, including medical treatments, environmental controls, and surgical treatments. Methods: In this study, a cross-sectional survey was conducted by internal medicine, pediatric, or otorhinolaryngology physicians at university hospitals from January 2022 to April 2022. A questionnaire was administered to patients with confirmed allergic rhinitis to collect information regarding medical treatments (prescription and over-the-counter medication use patterns, comorbid asthma, and allergen-specific immunotherapy), environmental controls (usage of air purifiers and pet avoidance), and experiences with surgical treatments. Results: We included 51 patients with allergic rhinitis with a mean age of 31.6±16.0 years. Among them, 47 (92.2%) and 6 (11.8%) patients had pollen allergies and asthma, respectively. Furthermore, 41 (80.4%) patients took prescribed medicines, while 39 (76.5%) patients only used the medication when experiencing symptoms. Thirty patients (58.8%) reported concurrent use of intranasal sprays and oral medications. Thirty-three patients (64.7%) reported awareness of immunotherapy, and there were no preferential differences between subcutaneous (52%) and sublingual immunotherapy (48%). Of the 36 patients (70.6%) who reported using an air purifier, 38.9% considered it helpful in preventing allergic rhinitis symptoms. Fourteen patients (27.5%) currently or previously had a companion animal, with half experiencing worsening of symptoms. Twelve patients had received surgical treatment and reported high satisfaction levels (41.6%, very satisfied; 41.6%, satisfied). Conclusion Patients with allergic rhinitis showed similar preferences for oral and spray medications. They also showed satisfaction with surgical treatments and an interest in the environmental management of allergic rhinitis.

Background and Objectives: The medications preferred by patients for allergic rhinitis and their usage remain unclear. This study investigated treatment-seeking behaviors in patients with allergic rhinitis, including medical treatments, environmental controls, and surgical treatments. Methods: In this study, a cross-sectional survey was conducted by internal medicine, pediatric, or otorhinolaryngology physicians at university hospitals from January 2022 to April 2022. A questionnaire was administered to patients with confirmed allergic rhinitis to collect information regarding medical treatments (prescription and over-the-counter medication use patterns, comorbid asthma, and allergen-specific immunotherapy), environmental controls (usage of air purifiers and pet avoidance), and experiences with surgical treatments. Results: We included 51 patients with allergic rhinitis with a mean age of 31.6±16.0 years. Among them, 47 (92.2%) and 6 (11.8%) patients had pollen allergies and asthma, respectively. Furthermore, 41 (80.4%) patients took prescribed medicines, while 39 (76.5%) patients only used the medication when experiencing symptoms. Thirty patients (58.8%) reported concurrent use of intranasal sprays and oral medications. Thirty-three patients (64.7%) reported awareness of immunotherapy, and there were no preferential differences between subcutaneous (52%) and sublingual immunotherapy (48%). Of the 36 patients (70.6%) who reported using an air purifier, 38.9% considered it helpful in preventing allergic rhinitis symptoms. Fourteen patients (27.5%) currently or previously had a companion animal, with half experiencing worsening of symptoms. Twelve patients had received surgical treatment and reported high satisfaction levels (41.6%, very satisfied; 41.6%, satisfied). Conclusion Patients with allergic rhinitis showed similar preferences for oral and spray medications. They also showed satisfaction with surgical treatments and an interest in the environmental management of allergic rhinitis.

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: Purse-string suture is a simple technique to reduce wound size and to achieve complete or partial closure of skin defects. Objective: To classify situations in which purse-string sutures can be utilized and to assess the long-term size reduction and cosmetic outcome of the final scar. Methods: Patients (93 from Severance hospital and 12 from Gangnam Severance hospital) in whom purse-string sutures were used between January 2015 and December 2019 were retrospectively reviewed. Wound site, final reconstruction method, repair duration, final wound size, and Vancouver scar scale were assessed. Results: A total of 105 patients were reviewed. Lesions were located on the trunk (48 [45.7%]), limbs (32 [30.5%]), and face (25 [23.8%]). Mean ratio of wound length/primary defect length was 0.79±0.30. Multilayered purse-string suture showed the shortest duration from excision to final repair (p<0.001) and most effectively minimized the scar size (scar to defect size ratio 0.67±0.23, p=0.002). The average Vancouver scar scale measured at the latest followup visit at least 6 months postoperatively was 1.62, and the risk of hypertrophic scarring was 8.6%. There was no significant difference in the Vancouver scar scale and the risk of hypertrophic scarring between the different surgical method groups. Conclusion Purse-string sutures can be utilized in many stages of reconstruction to effectively reduce scar size without compromising the final cosmetic outcome.