Purpose: Methacholine bronchial provocation tests (MBPTs) are commonly used to assess airway hyperresponsiveness, but some patients show no significant response. This study aimed to compare the clinical characteristics of asthmatic patients based on their sensitivity to MBPTs. Methods: We conducted a retrospective cross-sectional study involving adult asthmatic patients from 6 university hospitals in South Korea. Patients were categorized into 2 groups: those with MBPT sensitivity (the provocative concentration of methacholine that leads to a 20% reduction in forced expiratory volume in 1 second [PC20]≤ 16 mg/mL) and those with lower sensitivity (PC 20 > 16 mg/mL). Clinical characteristics were compared between the 2 groups. Results: Among 346 patients, 213 had PC 20 ≤ 16 mg/mL and 133 had PC 20 > 16 mg/mL. The PC20> 16 mg/mL group had a higher prevalence of late-onset asthma (P= 0.024) and obesity (P= 0.045). While no significant differences in immunoglobulin E (≥ 200 IU/mL) were found, the PC 20 ≤ 16 mg/mL group had greater T2-high inflammation, such as elevated eosinophil counts and fractional exhaled nitric oxide (P< 0.001 and P= 0.004, respectively). Asthma exacerbations requiring emergency visits or hospitalizations were more frequent in the PC 20 > 16 mg/mL group, despite a lower proportion of patients on higher-step treatments according to Global Initiative for Asthma guidelines. Conclusion Asthmatic patients with PC 20 > 16 mg/mL tend to present with late-onset asthma, less T2-high inflammation, and higher rates of asthma exacerbations. Further studies are needed to clarify the clinical features of asthma patients with PC 20 > 16 mg/mL and assess the long-term significance of these findings.

Purpose: Methacholine bronchial provocation tests (MBPTs) are commonly used to assess airway hyperresponsiveness, but some patients show no significant response. This study aimed to compare the clinical characteristics of asthmatic patients based on their sensitivity to MBPTs. Methods: We conducted a retrospective cross-sectional study involving adult asthmatic patients from 6 university hospitals in South Korea. Patients were categorized into 2 groups: those with MBPT sensitivity (the provocative concentration of methacholine that leads to a 20% reduction in forced expiratory volume in 1 second [PC20]≤ 16 mg/mL) and those with lower sensitivity (PC 20 > 16 mg/mL). Clinical characteristics were compared between the 2 groups. Results: Among 346 patients, 213 had PC 20 ≤ 16 mg/mL and 133 had PC 20 > 16 mg/mL. The PC20> 16 mg/mL group had a higher prevalence of late-onset asthma (P= 0.024) and obesity (P= 0.045). While no significant differences in immunoglobulin E (≥ 200 IU/mL) were found, the PC 20 ≤ 16 mg/mL group had greater T2-high inflammation, such as elevated eosinophil counts and fractional exhaled nitric oxide (P< 0.001 and P= 0.004, respectively). Asthma exacerbations requiring emergency visits or hospitalizations were more frequent in the PC 20 > 16 mg/mL group, despite a lower proportion of patients on higher-step treatments according to Global Initiative for Asthma guidelines. Conclusion Asthmatic patients with PC 20 > 16 mg/mL tend to present with late-onset asthma, less T2-high inflammation, and higher rates of asthma exacerbations. Further studies are needed to clarify the clinical features of asthma patients with PC 20 > 16 mg/mL and assess the long-term significance of these findings.

Purpose: Methacholine bronchial provocation tests (MBPTs) are commonly used to assess airway hyperresponsiveness, but some patients show no significant response. This study aimed to compare the clinical characteristics of asthmatic patients based on their sensitivity to MBPTs. Methods: We conducted a retrospective cross-sectional study involving adult asthmatic patients from 6 university hospitals in South Korea. Patients were categorized into 2 groups: those with MBPT sensitivity (the provocative concentration of methacholine that leads to a 20% reduction in forced expiratory volume in 1 second [PC20]≤ 16 mg/mL) and those with lower sensitivity (PC 20 > 16 mg/mL). Clinical characteristics were compared between the 2 groups. Results: Among 346 patients, 213 had PC 20 ≤ 16 mg/mL and 133 had PC 20 > 16 mg/mL. The PC20> 16 mg/mL group had a higher prevalence of late-onset asthma (P= 0.024) and obesity (P= 0.045). While no significant differences in immunoglobulin E (≥ 200 IU/mL) were found, the PC 20 ≤ 16 mg/mL group had greater T2-high inflammation, such as elevated eosinophil counts and fractional exhaled nitric oxide (P< 0.001 and P= 0.004, respectively). Asthma exacerbations requiring emergency visits or hospitalizations were more frequent in the PC 20 > 16 mg/mL group, despite a lower proportion of patients on higher-step treatments according to Global Initiative for Asthma guidelines. Conclusion Asthmatic patients with PC 20 > 16 mg/mL tend to present with late-onset asthma, less T2-high inflammation, and higher rates of asthma exacerbations. Further studies are needed to clarify the clinical features of asthma patients with PC 20 > 16 mg/mL and assess the long-term significance of these findings.

Purpose: Methacholine bronchial provocation tests (MBPTs) are commonly used to assess airway hyperresponsiveness, but some patients show no significant response. This study aimed to compare the clinical characteristics of asthmatic patients based on their sensitivity to MBPTs. Methods: We conducted a retrospective cross-sectional study involving adult asthmatic patients from 6 university hospitals in South Korea. Patients were categorized into 2 groups: those with MBPT sensitivity (the provocative concentration of methacholine that leads to a 20% reduction in forced expiratory volume in 1 second [PC20]≤ 16 mg/mL) and those with lower sensitivity (PC 20 > 16 mg/mL). Clinical characteristics were compared between the 2 groups. Results: Among 346 patients, 213 had PC 20 ≤ 16 mg/mL and 133 had PC 20 > 16 mg/mL. The PC20> 16 mg/mL group had a higher prevalence of late-onset asthma (P= 0.024) and obesity (P= 0.045). While no significant differences in immunoglobulin E (≥ 200 IU/mL) were found, the PC 20 ≤ 16 mg/mL group had greater T2-high inflammation, such as elevated eosinophil counts and fractional exhaled nitric oxide (P< 0.001 and P= 0.004, respectively). Asthma exacerbations requiring emergency visits or hospitalizations were more frequent in the PC 20 > 16 mg/mL group, despite a lower proportion of patients on higher-step treatments according to Global Initiative for Asthma guidelines. Conclusion Asthmatic patients with PC 20 > 16 mg/mL tend to present with late-onset asthma, less T2-high inflammation, and higher rates of asthma exacerbations. Further studies are needed to clarify the clinical features of asthma patients with PC 20 > 16 mg/mL and assess the long-term significance of these findings.

Purpose: Methacholine bronchial provocation tests (MBPTs) are commonly used to assess airway hyperresponsiveness, but some patients show no significant response. This study aimed to compare the clinical characteristics of asthmatic patients based on their sensitivity to MBPTs. Methods: We conducted a retrospective cross-sectional study involving adult asthmatic patients from 6 university hospitals in South Korea. Patients were categorized into 2 groups: those with MBPT sensitivity (the provocative concentration of methacholine that leads to a 20% reduction in forced expiratory volume in 1 second [PC20]≤ 16 mg/mL) and those with lower sensitivity (PC 20 > 16 mg/mL). Clinical characteristics were compared between the 2 groups. Results: Among 346 patients, 213 had PC 20 ≤ 16 mg/mL and 133 had PC 20 > 16 mg/mL. The PC20> 16 mg/mL group had a higher prevalence of late-onset asthma (P= 0.024) and obesity (P= 0.045). While no significant differences in immunoglobulin E (≥ 200 IU/mL) were found, the PC 20 ≤ 16 mg/mL group had greater T2-high inflammation, such as elevated eosinophil counts and fractional exhaled nitric oxide (P< 0.001 and P= 0.004, respectively). Asthma exacerbations requiring emergency visits or hospitalizations were more frequent in the PC 20 > 16 mg/mL group, despite a lower proportion of patients on higher-step treatments according to Global Initiative for Asthma guidelines. Conclusion Asthmatic patients with PC 20 > 16 mg/mL tend to present with late-onset asthma, less T2-high inflammation, and higher rates of asthma exacerbations. Further studies are needed to clarify the clinical features of asthma patients with PC 20 > 16 mg/mL and assess the long-term significance of these findings.

Purpose: Contact dermatitis (CD) is a common skin disease caused by various allergens that can be identified by patch test (PT). Despite the analysis of PT outcomes in various regions of Korea, no specific investigation has targeted the Busan area. We aimed to analyze PT results using Chemotechnique in patients suspected of CD in Busan. Methods: We reviewed medical records of 273 patients who underwent PT between 2019 and 2020 at two university hospitals in Busan. PT results were interpreted according to the International Contact Dermatitis Research Group criteria. Results: Among the patients, 86.4% exhibited positive reactions to at least one allergen. Those with positive outcomes displayed a higher comorbidity rate of chronic urticaria but a lower rate of atopic dermatitis. Moreover, they reported higher positivity rates to questions about sexual life and treatment on the Dermatology Life Quality Index questionnaire. Major allergens in Busan were cobalt chloride (60.1%), nickel sulfate (52.0%), and potassium dichromate (50.9%), followed by thiomersal, balsam of Peru, and fragrance mix (17.2%, 15.4%, and 13.9%, respectively). Captan, budesonide, and colophony were more prevalent allergens in males. While the positive rate for thiomersal were higher in the younger age group, balsam of Peru allergen was higher in the older age group. Conclusion This study represents the first PT analysis conducted in Busan, revealing metal-related allergen as the most common cause of CD, with variations observed across sex and age. Further research is needed to validate these findings and elucidate the sources and pathways of allergen exposure in Busan.

Background: Autologous blood therapy (ABT) has been used to treat atopic dermatitis (AD) for over a century, even though evidence supporting its efficacy is lacking. We aimed to investigate the effectiveness and safety of autologous serum intramuscular injection (ASIM), which is a modified form of ABT, in treating mild-to-moderate AD. Methods: This study was a 12-week, open-label, prospective, uncontrolled trial. Following a 4-week run-in period, 22 out of 25 screened patients received ASIM once a week for 4 weeks in conjunction with standard treatment. The primary outcome measure was the Eczema Area and Severity Index (EASI), while the secondary outcomes included the Scoring Atopic Dermatitis (SCORAD) score, Dermatologic Life Quality Index (DLQI), and patient ratings of pruritus, sleep difficulty, disease status, and treatment effectiveness. Safety parameters were also assessed. Results: EASI scores showed a non-statistically significant trend toward improvement during ASIM intervention. Patients with at least a 50% improvement in the EASI score at 4 weeks were older and had lower peripheral eosinophil counts (p<0.05). Secondary endpoints, including the SCORAD score, pruritus, sleep difficulty, and DLQI, demonstrated statistically significant improvements at week 4 compared to baseline (p<0.05). No significant adverse reactions were observed. Conclusions This pioneering study suggests that repeated ASIM may improve the clinical symptoms of mild-to-moderate AD, particularly in terms of pruritus and overall quality of life. However, further research with a larger sample size is required to establish the clinical significance of these findings.

Background/Aims: We aimed to compare the effectiveness and safety of Janus kinase inhibitors (JAKi) vs. biologic disease- modifying antirheumatic drugs (bDMARD) in Korean patients with rheumatoid arthritis (RA) who had an inadequate response to conventional synthetic DMARDs. Methods: A quasi-experimental, multi-center, prospective, non-randomized study was conducted to compare response rates between JAKi and bDMARDs in patients with RA naïve to targeted therapy. An interim analysis was performed to estimate the proportion of patients achieving low disease activity (LDA) based on disease activity score (DAS)–28– erythroid sedimentation rate (ESR) (DAS28-ESR) at 24 weeks after treatment initiation and to evaluate the development of adverse events (AEs). Results: Among 506 patients enrolled from 17 institutions between April 2020 and August 2022, 346 (196 JAKi group and 150 bDMARD group) were included in the analysis. After 24 weeks of treatment, 49.0% of JAKi users and 48.7% of bDMARD users achieved LDA (p = 0.954). DAS28-ESR remission rates were also comparable between JAKi and bDMARD users (30.1% and 31.3%, respectively; p = 0.806). The frequency of AEs reported in the JAKi group was numerically higher than that in the bDMARDs group, but the frequencies of serious and severe AEs were comparable between the groups. Conclusions Our interim findings reveal JAKi have comparable effectiveness and safety to bDMARDs at 24 weeks after treatment initiation.

Allergic rhinitis is the most common chronic disease worldwide. Various upper airway symptoms lower quality of life, and due to the recurrent symptoms, multiple treatments are usually attempted rather than one definitive treatment. There are alternatives to medical (medication-based) and nonmedical treatments. A guideline is needed to understand allergic rhinitis and develop an appropriate treatment plan. We have developed guidelines for medical treatment based on previous reports. The current guidelines herein are associated with the “KAAACI Evidence-Based Guidelines for Allergic Rhinitis in Korea, Part 1: Update in pharmacotherapy” in which we aimed to provide evidence-based recommendations for the medical treatment of allergic rhinitis. Part 2 focuses on nonpharmacological management, including allergen-specific immunotherapy, subcutaneous or sublingual immunotherapy, nasal saline irrigation, environmental management strategies, companion animal management, and nasal turbinate surgery. The evidence to support the treatment efficacy, safety, and selection has been systematically reviewed. However, larger controlled studies are needed to elevate the level of evidence to select rational non-medical therapeutic options for patients with allergic rhinitis.

The prevalence of allergic rhinitis (AR) and the socioeconomic burden associated with the medical cost and quality of life of AR have progressively increased. Therefore, practical guidelines for the appropriate management of AR need to be developed based on scientific evidence considering the real-world environment, values, and preferences of patients and physicians. The Korean Academy of Asthma, Allergy and Clinical Immunology revised clinical guidelines for AR to address key clinical questions of the management of AR. Part 1 of the revised guideline covers the pharmacological management of patients with AR in Korea. Through a meta-analysis and a systematic review, we made 4 recommendations for AR pharmacotherapy, including intranasal corticosteroid (INCS)/intranasal antihistamine combination therapy, oral antihistamine/INCS combination therapy, leukotriene receptor antagonist treatment in AR patients with asthma, and prophylactic treatment for patients with pollen-induced AR. However, all recommendations are conditional because of the low or very low evidence of certainty. Well-designed and strictly executed randomized controlled trials are needed to measure and report appropriate outcomes.