Objectives: In May 2025, clusters of salmonellosis were identified in 7 cities in the Republic of Korea, all associated with consumption of identical bakery products. This investigation aimed to characterize the outbreak, identify potential contributing factors, and inform strategies for preventing similar multi-facility foodborne outbreaks. Methods: A case series study was conducted among individuals who consumed Manufacturer H’s Product I and Product II on May 15–16, 2025 at 7 facilities (n = 1,235). Clinical specimens from symptomatic individuals, retained food samples, and environmental samples were collected and tested. Food-exposure histories were assessed, and active case finding was implemented across all supplied facilities. Traceback investigations were conducted at the manufacturer, distributor, and egg farms. Human and food isolates underwent pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS). Results: A total of 323 cases met the outbreak case definition (attack rate, 26.2%), of which 48 were laboratory-confirmed. Salmonella Enteritidis was isolated from both clinical specimens and retained bakery products. PFGE patterns were indistinguishable between human and food isolates, and WGS demonstrated high genetic relatedness. These findings confirmed a common-source outbreak linked to the implicated bakery products. Conclusion This outbreak underscores the value of integrating epidemiological investigation, active case finding, and molecular typing to identify common food vehicles in outbreaks involving widely distributed manufactured foods. Coordinated collaboration between public health and food safety authorities is essential for the effective detection, response, and prevention of multi-facility foodborne outbreaks.

Background: With the aging population and advancements in medical care worldwide, the number of older patients with end-stage kidney disease continues to rise. This study aimed to identify factors associated with osteoporosis and osteopenia in older patients undergoing incident hemodialysis and assess their impact on mortality. Methods: We analyzed a large multicenter retrospective cohort of patients aged ≥70 years undergoing incident hemodialysis to identify factors associated with osteoporosis using logistic regression analysis and to assess the association of death with osteoporosis and osteopenia using Cox multivariable analysis. Results: Among 710 patients, 39.0% and 19.6% had osteoporosis and osteopenia, respectively. Osteoporosis was significantly associated with female sex, a history of fractures, and the absence of phosphate binder use. During a median follow-up of 36.8 months, 348 participants (58.8%) died. Mortality rates were the highest in the osteoporosis group (79.8%), followed by the osteopenia (77.2%) and normal bone mineral density (BMD) groups (35.2%). Cox regression analysis revealed that even after adjusting for covariates, the osteoporosis group was significantly associated with a higher mortality risk than the normal BMD group. Osteoporosis at the start of hemodialysis was significantly associated with higher mortality. Conclusion We should consider the importance of bone health in patients undergoing incident hemodialysis and pay attention to the use of phosphate binders and fracture prevention.

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.

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.

Obstructive sleep apnea (OSA) is a common disorder characterized by upper airway obstruction during sleep. To reduce the morbidity of OSA, sleep specialists have explored various methods of managing the condition, including manifold positive airway pressure (PAP) techniques and surgical procedures. Nasal obstruction can cause significant discomfort during sleep, and it is likely that improving nasal obstruction would enhance the quality of life and PAP compliance of OSA patients. Many reliable studies have offered evidence to support this assumption. However, few comprehensive guidelines for managing OSA through nasal surgery encompass all this evidence. In order to address this gap, the Korean Society of Otorhinolaryngology-Head and Neck Surgery (KORL-HNS) and the Korean Society of Sleep and Breathing designated a guideline development group (GDG) to develop recommendations for nasal surgery in OSA patients. Several databases, including OVID Medline, Embase, the Cochrane Library, and KoreaMed, were searched to identify all relevant papers using a predefined search strategy. The types of nasal surgery included septoplasty, turbinate surgery, nasal valve surgery, septorhinoplasty, and endoscopic sinus surgery. When insufficient evidence was found, the GDG sought expert opinions and attempted to fill the evidence gap. Evidence-based recommendations for practice were ranked according to the American College of Physicians’ grading system. The GDG developed 10 key action statements with supporting text to support them. Three statements are ranked as strong recommendations, three are only recommendations, and four can be considered options. The GDG hopes that this clinical practice guideline will help physicians make optimal decisions when caring for OSA patients. Conversely, the statements in this guideline are not intended to limit or restrict physicians’ care based on their experience and assessment of individual patients.

Background: Dermatophyte infection is one of the most common skin diseases affecting the skin, hair, and nails. Despite widespread recognition of the disease, missing details and misperceptions are commonplace in the general population. Objective: This study aimed to investigate the public perception and behavior regarding dermatophytosis of the hands and feet. Methods: This results from an online survey conducted between July 2022 and August 2022. The survey included 1,000 Korean participants aged 20 to 69 years, of whom 60% experienced symptoms of tinea pedis or onychomycosis. The questionnaire focused on the awareness and personal experience of tinea pedis and perception of the treatment of dermatophytosis. Results: Of the 1,000 participants, nearly 80% regarded tinea pedis as a common skin condition by which anyone can be affected. Furthermore, 88.4% had heard that the treatment of tinea pedis could be harmful, causing skin rash (60.4%) and worsening liver function (48.5%). Among 896 participants who noticed suspicious symptoms, 81.2% did not visit the clinic because it was not severe (50.1%) and seemed easily manageable (25.7%). Of the respondents, 84.4% preferred to meet dermatologists rather than non-dermatologist doctors regarding skin diseases, mainly because of trust in experts and belief in a faster cure. Conclusion Providing accurate and detailed information via online media, educational campaigns, and medical papers can rectify misconceptions and improve patient appliance, contributing to public skin health.

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.

Background/Aims: Besifovir dipivoxil maleate (BSV), an acyclic nucleotide phosphonate, shows potent antiviral activity against hepatitis B virus. Our previous 48-week trial revealed that BSV has comparable antiviral efficacy to tenofovir disoproxil fumarate (TDF) and better safety profiles in terms of improved renal and bone safety. This extension study evaluated the prolonged efficacy and safety of BSV in treatment-naive chronic hepatitis B patients. Methods: Patients continued to participate in an open-label BSV study after an initial 48-week double-blind comparison of BSV and TDF treatment. The antiviral efficacy and drug safety was evaluated up to 192 weeks in two groups: patients continuing BSV treatment (BSV-BSV) and patients switching from TDF to BSV after 48 weeks (TDF-BSV). Results: Among 197 patients receiving randomized treatments, 170 (86%) entered the open-label phase and 152 (77%) entered the 192-week extension study. Virological response rates over 192 weeks were 92.50% and 93.06% in the BSV-BSV and TDF-BSV groups, respectively (P=0.90). Hepatitis B envelop antigen seroconversion and alanine aminotransferase normalization rates were similar between the groups (P=0.75 and P=0.36, respectively). There were no drug-resistant mutations to BSV. Bone mineral density and renal function were well preserved in the BSV-BSV group, whereas these initially worsened then recovered after switching therapy in the TDF-BSV group. Conclusions BSV maintained potent antiviral efficacy after 192 weeks and showed no evidence of drug resistance. BSV was safe, well tolerated, and effective in patients who switched from TDF to BSV. Trial Registration Number: NCT01937806 (date: 10 Sep 2013).

Background: We analyzed cell-free serum Epstein‒Barr virus (EBV) DNA to identify its prognostic role in patients with newly diagnosed lymphoma. Methods: We retrospectively reviewed patients diagnosed with lymphoma between January 2014 and July 2020. Patients were enrolled according to the following criteria: i) pathologically confirmed lymphomas according to the World Health Organization criteria, ii) age over 18 years, iii) serum EBV DNA measurement using polymerase chain reaction prior to first-line therapy, and iv) receipt of curative standard chemotherapy. In total, 263 patients met these criteria and were included in this study. Results: Serum EBV DNA was detected in 79 patients (30.0%). Patients with positive serum EBV tended to be older (P =0.090), and the proportion of T-cell lineage lymphomas was higher than that of B-cell lymphomas (P =0.003). EBV positivity was significantly associated with more advanced disease based on the Ann Arbor staging system (P =0.008) and the International Prognostic Index (P =0.009). EBV positivity was also associated with higher disease relapse (P =0.038) and death rates (P =0.005). EBV-positive lymphomas further showed inferior long-term survival outcomes in terms of progression-free survival (PFS) (P =0.053) and overall survival (OS) (P =0.014). In the subgroup analyses, serum EBV positivity was a significant prognostic factor for patients with B-cell lineage lymphomas in terms of PFS (P =0.003) and OS (P =0.033). Conclusion We demonstrated that cell-free serum EBV DNA status at the time of diagnosis has potential as a prognostic biomarker for patients with newly diagnosed malignant lymphomas.