Objectives: The coronavirus disease 2019 (COVID-19) pandemic has continued since its first detection in the Republic of Korea on January 20, 2020. This study describes the early countermeasures used to minimize the risk of COVID-19 outbreaks during cohort quarantine and compares the epidemiological characteristics of 2 outbreaks in long-term care facilities (LTCFs) in Gwangju Metropolitan City in summer 2020. Methods: An epidemiological investigation was conducted via direct visits. We investigated epidemiological characteristics, including incidence, morbidity, and mortality rates, for all residents and staff members. Demographic characteristics were analyzed using a statistical program. Additionally, the method of managing infection in LTCFs is described. Results: Residents and caregivers had high incidence rates in LTCF-A and LTCF-B, respectively. LTCF-B had a longer quarantine period than LTCF-A. The attack rate was 20.02% in LTCF-A and 27.9% in LTCF- B. The mortality rate was 2.3% (1/43) in LTCF-B, the only facility in which a COVID-19 death occurred. Conclusion Extensive management requires contact minimization, which involves testing all contacts to mitigate further transmission in the early stages of LTCF outbreaks. The findings of this study can help inform and prepare public health authorities for COVID-19 outbreaks, particularly for early control in vulnerable facilities.

Objectives: We evaluated the effectiveness of coronavirus disease 2019 vaccination in high-risk facilities in the Republic of Korea during the period when the highly transmissible Delta variant was prevalent. Additionally, we aimed to explore any disparities in vaccine effectiveness (VE) across various types of institutions, specifically distinguishing between non-medical and medical establishments. Methods: We examined 8 outbreak clusters covering 243 cases and 895 contacts from 8 highrisk facilities divided into 2 groups: group A (4 non-medical institutions) and group B (4 medical institutions). These clusters were observed from July 27, 2021 to October 16, 2021 for the attack rate (AR) and VE with respect to disease severity. A generalized linear model with a binomial distribution was used to determine the odds ratio (OR) for disease severity and death. Results: AR was notably lower in group B (medical institutions). Furthermore, VE analysis revealed that group A exhibited higher effectivity for disease severity and death than group B. The OR for disease severity was 0.24 (95% confidence interval [CI], 0.03–2.16) for group A and 0.27 (95% CI, 0.12–0.64) for group B, with the OR for death at 0.12 (95% CI, 0.01–1.32) in group A and 0.34 (95% CI, 0.14–0.87) in group B. Conclusion Although VE may vary across institutions, our findings underscore the importance of implementing vaccinations in high-risk facilities. Customized vaccination programs, tailored response plans, and competent management personnel are essential for effectively addressing and mitigating public health challenges.

Purpose: We aimed to compare the oncological outcomes and toxicities of definitive proton beam therapy (PBT) and photon beam therapy in patients with limited-stage small cell lung cancer (LS-SCLC). Materials and Methods: We retrospectively reviewed 262 patients with newly diagnosed LS-SCLC who underwent definitive PBT (n = 20; proton group) or photon beam therapy (n = 242; photon group) with concurrent chemotherapy between January 2016 and February 2021 and compared overall survival (OS), progression-free survival (PFS), dose-volume parameters, and toxicities between the groups. Results: The median follow-up duration was 24.5 months (range, 3.7 to 78.7). Baseline lung function was significantly worse and clinical target volume (CTV) was larger in the proton group (CTV: 296.6 vs. 215.3 mL; p = 0.080). The mean lung V10 was 37.7% ± 16.8% and 51.6% ± 24.5% in the proton and photon groups, respectively (p = 0.002). Two-year OS and PFS rates were 57.2% and 35.7% in the proton group and 65.3% and 40.8% in the photon group, respectively (p = 0.542 and 0.748, respectively). Grade ≥2 radiation pneumonitis and esophagitis occurred in 5 (25.0%) and 7 (35.0%) PBT-treated patients and 66 (27.3%) and 40 (16.5%) photon beam therapy-treated patients, respectively (p = 0.826 and 0.062, respectively). Conclusion Although the proton group had poorer lung function and a larger CTV than that in the photon group, both groups exhibited comparable treatment outcomes and radiation-related toxicities in LS-SCLC. PBT may be a valuable therapeutic modality in patients with poor pulmonary function or extensive disease burden owing to its lung-sparing ability.

In November 2021, 14 international travel-related severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (omicron) variant of concern (VOC) patients were detected in South Korea. Epidemiologic investigation revealed community transmission of the omicron VOC. A total of 80 SARS-CoV-2 omicron VOC-positive patients were identified until December 10, 2021 and 66 of them reported no relation to the international travel.There may be more transmissions with this VOC in Korea than reported.

Objective: We investigated the prevalence of pneumonia in novel coronavirus disease 2019 (COVID-19) patients using chest radiographs to identify the characteristics of those with initially negative chest radiographs, who were positive for pneumonia on follow-up. Materials and Methods: Retrospective cohort data of 236 COVID-19 patients were reviewed. Chest radiography was performed on admission, with serial radiographs obtained until discharge. The ‘positive conversion group’ was defined as patients whose initial chest radiographs were negative but were positive for pneumonia during follow-up. Patients with initially positive chest radiographs were defined as the ‘initial pneumonia group.’ Patients with negative initial and follow-up chest radiographs were defined as the ‘non-pneumonia group.’ Clinical and laboratory findings were compared between groups, and predictors of positive conversion were investigated. Results: Among 236 patients, 108 (45.8%) were in the non-pneumonia group, 69 (29.2%) were in the initial pneumonia group, and 59 (25%) were in the positive conversion group. The patients in the ‘initial pneumonia group’ and ‘positive conversion group’ were older, had higher C-reactive protein (CRP) and lactate dehydrogenase levels, and lower absolute lymphocyte counts than those in the ‘non-pneumonia group’ (all p < 0.001). Among patients with negative initial chest radiographs, age ≥ 45 years (odds ratio [OR]: 3.93, 95% confidence interval [CI]: 1.76–8.75, p = 0.001), absolute lymphocyte count < 1500 cells/µL (OR: 2.25, 95% CI: 1.03–4.89,p = 0.041), and CRP > 0.5 mg/dL (OR: 3.91, 95% CI: 1.54–9.91, p = 0.004) were independent predictors for future development of pneumonia. Conclusion More than a half of COVID-19 patients initially had normal chest radiographs; however, elderly patients (≥ 45 years of age) with abnormal laboratory findings (elevated CRP and low absolute lymphocyte counts) developed pneumonia on follow-up radiographs.

BACKGROUND: Laser therapy can be used as an alternative treatment for onychomycosis; however, there are somelimitations to its efficacy as a single agent. OBJECTIVE: To evaluate the effectiveness of combination therapy with 1,064-nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser and topical efinaconazole in onychomycosis treatment and identify factors influencing the therapeutic outcomes of combination treatment. METHODS: Big toenails with onychomycosis were treated by 1,064-nm Nd:YAG laser at 4-week intervals with daily application of topical efinaconazole. Therapeutic response was assessed through onychomycosis severity index (OSI) and percentage of nail infected (PNI), and its association with a variety of factors that may affect treatment outcome was evaluated. RESULTS: One hundred big toenails were included in the study and significant clinical improvements were observed after treatment (OSI improvement score = 76.68 ± 28.83, PNI improvement score = 72.37 ± 30.37). There was no difference in treatment response according to the number of laser treatments, onychomycosis clinical type, or initial severity. However, patient age was negatively correlated with clinical improvement (p = 0.019). Also, female patients had better therapeutic responses than male patients. CONCLUSION Combined treatment with Nd:YAG laser and topical efinaconazole has a significant therapeutic effect on onychomycosis. A randomized controlled trial is warranted in the future.

PURPOSE: This study was conducted to evaluate the relationship between epidermal growth factor receptor (EGFR) mutation and clinical outcomes in patients with stage III non-squamous cell lung cancer treated with definitive concurrent chemoradiotherapy (CCRT). MATERIALS AND METHODS: From January 2008 to December 2013, the medical records of 197 patients with stage III non- squamous non-small cell lung cancer treated with definitive CCRT were analyzed to determine progression-free survival (PFS) and overall survival (OS) according to EGFR mutation status. RESULTS: Among 197 eligible patients, 81 patients were EGFR wild type, 36 patients had an EGFR mutation (exon 19 Del, n=18; L858R, n=9, uncommon [G719X, L868, T790M], n=9), and 80 patients had unknown EGFR status. The median age was 59 years (range, 28 to 80 years) and 136 patients (69.0%) were male. The median follow-up duration was 66.5 months (range, 1.9 to 114.5 months). One hundred sixty-four patients (83.2%) experienced disease progression. Median PFS was 8.9 months for the EGFR mutation group, 11.8 months for EGFR wild type, and 10.5 months for the unknown EGFR group (p=0.013 and p=0.042, respectively). The most common site of metastasis in the EGFR mutant group was the brain. However, there was no significant difference in OS among the three groups (34.6 months for EGFR mutant group vs. 31.9 months for EGFR wild type vs. 22.6 months for EGFR unknown group; p=0.792 and p=0.284). A total of 29 patients (80.6%) with EGFR mutation were treated with EGFR tyrosine kinase inhibitor (gefitinib, n=24; erlotinib, n=3; afatinib, n=2) upon progression. CONCLUSION: EGFR mutation is associatedwith short PFS and the brain is the most common site of distant metastasis in patients with stage III non- squamous cell lung cancer treated with CCRT.
Brain ; Carcinoma, Non-Small-Cell Lung ; Chemoradiotherapy ; Disease Progression ; Disease-Free Survival ; Epithelial Cells ; Erlotinib Hydrochloride ; Follow-Up Studies ; Humans ; Lung Neoplasms ; Lung ; Male ; Medical Records ; Neoplasm Metastasis ; Protein-Tyrosine Kinases ; Receptor, Epidermal Growth Factor

No abstract available.
Aluminum* ; Onychomycosis* ; Yttrium*

PURPOSE: Vitiligo prevalence and its associated comorbidities rate have been reported variably among different populations. We aimed to determine the prevalence of vitiligo in Korea along with the baseline rate of comorbidities and compared the risks to the general population using hospital visit information of the total population in Korea. MATERIALS AND METHODS: We assessed demographic characteristics of vitiligo patients in Korean population from 2009 to 2011 in a nationwide data from Health Insurance Review Assessment Service. Patients who had at least one visit to Korea's primary, secondary, or tertiary referral hospitals with International Classification of Diseases, 10th Revision, Clinical Modification diagnosis code for vitiligo were identified. As a supplementary study, comorbidities associated with vitiligo were selected for further review to calculate relative risks compared to the general population. RESULTS: The annual prevalence of vitiligo determined by hospital-visiting rate in Korea was 0.12% to 0.13% over a three year period. In sync with other previous epidemiological studies, there was bimodal distribution among the age groups and no difference between genders. Also, vitiligo in Korean population was associated with various autoimmune/non-autoimmune diseases such as thyroiditis, atopic dermatitis, and psoriasis. CONCLUSION: This study was by far the most comprehensive review on prevalence of vitiligo using a data of total population in Korea. The prevalence is within a range of those reported in previous literatures, and increased risk of comorbidities such as thyroid diseases and psoriasis in vitiligo might aid clinicians in the initial work up of vitiligo patients and concurrent follow ups.
Adult ; Aged ; Autoimmune Diseases/*epidemiology/immunology ; Comorbidity ; Diabetes Mellitus, Type 1/epidemiology ; Female ; Humans ; Male ; Middle Aged ; Population Surveillance ; Prevalence ; Republic of Korea/epidemiology ; Socioeconomic Factors ; Thyroid Diseases/epidemiology ; Vitiligo/*epidemiology

BACKGROUND: It was previously thought that persons with genetic predispositions to vitiligo develop the condition after exposure to various precipitating environmental factors. However, in many cases, the aggravating factors of vitiligo have not been clearly identified. OBJECTIVE: To identify the aggravating factors of vitiligo in the working environment and daily life. METHODS: A total of 489 vitiligo patients were recruited from 10 institutions in South Korea; patients were provided with a questionnaire about environmental factors and behavior patterns in the workplace and in daily life, and their association with vitiligo. RESULTS: Ninety-five of the 470 enrolled patients (20.2%) answered that environmental risk factors in daily life and in the workplace affected the development of vitiligo. The most frequently attributed causes were trauma and burn (13.6%), followed by sunlight (12.8%), stress (12.8%), cleaning products/disinfectant/chemicals (4.9%), and hair dye (2.1%). CONCLUSION: Vitiligo of the hand and foot was associated with frequent exposure to aggravating materials and overexposure to sunlight, along with frequent trauma of these areas, all of which could be considered important risk factors of vitiligo. The development of vitiligo could potentially be controlled through the early detection of aggravating factors.
Burns ; Foot ; Genetic Predisposition to Disease ; Hair ; Hand ; Humans ; Korea ; Occupations* ; Risk Factors ; Sunlight ; Vitiligo* ; Surveys and Questionnaires