Background: The coronavirus disease 2019 (COVID-19) pandemic has caused the death of thousands of patients worldwide. Although age is known to be a risk factor for morbidity and mortality in COVID-19 patients, critical illness or death is occurring even in the younger age group as the epidemic spreads. In early 2022, omicron became the dominant variant of the COVID-19 virus in South Korea, and the epidemic proceeded on a large scale. Accordingly, this study aimed to determine whether young adults (aged ≤ 50 years) with critical COVID-19 infection during the omicron period had different characteristics from older patients and to determine the risk factors for mortality in this specific age group. Methods: We evaluated 213 critical adult patients (high flow nasal cannula or higher respiratory support) hospitalized for polymerase chain reaction-confirmed COVID-19 in nine hospitals in South Korea between February 1, 2022 and April 30, 2022. Demographic characteristics, including body mass index (BMI) and vaccination status; underlying diseases; clinical features and laboratory findings; clinical course; treatment received; and outcomes were collected from electronic medical records (EMRs) and analyzed according to age and mortality. Results: Overall, 71 critically ill patients aged ≤ 50 years were enrolled, and 142 critically ill patients aged over 50 years were selected through 1:2 matching based on the date of diagnosis. The most frequent underlying diseases among those aged ≤ 50 years were diabetes and hypertension, and all 14 patients who died had either a BMI ≥ 25 kg/m 2 or an underlying disease. The total case fatality rate among severe patients (S-CFR) was 31.0%, and the S-CFR differed according to age and was higher than that during the delta period. The S-CFR was 19.7% for those aged ≤ 50 years, 36.6% for those aged > 50 years, and 38.1% for those aged ≥ 65 years. In multivariate analysis, age (odds ratio [OR], 1.084; 95% confidence interval [CI], 1.043–1.127), initial low-density lipoprotein > 600 IU/L (OR, 4.782; 95% CI, 1.584–14.434), initial C-reactive protein > 8 mg/dL (OR, 2.940; 95% CI, 1.042–8.293), highest aspartate aminotransferase > 200 IU/L (OR, 12.931; 95% CI, 1.691–98.908), and mechanical ventilation implementation (OR, 3.671; 95% CI, 1.294–10.420) were significant independent predictors of mortality in critical COVID-19 patients during the omicron wave. A similar pattern was shown when analyzing the data by age group, but most had no statistical significance owing to the small number of deaths in the young critical group. Although the vaccination completion rate of all the patients (31.0%) was higher than that in the delta wave period (13.6%), it was still lower than that of the general population. Further, only 15 (21.1%) critically ill patients aged ≤ 50 years were fully vaccinated. Overall, the severity of hospitalized critical patients was significantly higher than that in the delta period, indicating that it was difficult to find common risk factors in the two periods only with a simple comparison. Conclusion Overall, the S-CFR of critically ill COVID-19 patients in the omicron period was higher than that in the delta period, especially in those aged ≤ 50 years. All of the patients who died had an underlying disease or obesity. In the same population, the vaccination rate was very low compared to that in the delta wave, indicating that non-vaccination significantly affected the progression to critical illness. Notably, there was a lack of prescription for Paxlovid for these patients although they satisfied the prescription criteria. Early diagnosis and active initial treatment was necessary, along with the proven methods of vaccination and personal hygiene. Further studies are needed to determine how each variant affects critically ill patients.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and lethal lung disease characterized by progressive dyspnea and irreversible loss of lung function. Pirfenidone is a novel anti-fibrotic and anti-inflammatory drug, which reduces deterioration in the lung function and prolongs progression-free survival in patients with IPF. However, ithas adverse effects including gastrointestinal symptoms, hepatic dysfunction or skin photosensitivity, and rash. Lichenoid drug eruption (LDE) refers to lichen planuslike drug eruption usually presenting symmetric eczematous plaques with a purple hue. To date, numerous cases of LDE due to various drugs and pirfenidone-associated photosensitivity have been reported. However, a case of pirfenidone-induced LDE has been very rarely reported to our knowledge. Herein, is a case of pirfenidone-induced LDE so that clinicians can be aware of the possibility of LDE when using pirfenidone.

Background: Numerous patients around the globe are dying from coronavirus disease 2019 (COVID-19). While age is a known risk factor, risk analysis in the young generation is lacking. The present study aimed to evaluate the clinical features and mortality risk factors in younger patients (≤ 50 years) with a critical case of COVID-19 in comparison with those among older patients (> 50 years) in Korea. Methods: We analyzed the data of adult patients only in critical condition (requiring high flow nasal cannula oxygen therapy or higher respiratory support) hospitalized with PCR-confirmed COVID-19 at 11 hospitals in Korea from July 1, 2021 to November 30, 2021 when the delta variant was a dominant strain. Patients’ electronic medical records were reviewed to identify clinical characteristics. Results: During the study period, 448 patients were enrolled. One hundred and forty-two were aged 50 years or younger (the younger group), while 306 were above 50 years of age (the older group). The most common pre-existing conditions in the younger group were diabetes mellitus and hypertension, and 69.7% of the patients had a body mass index (BMI) > 25 kg/m 2 .Of 142 younger patients, 31 of 142 patients (21.8%, 19 women) did not have these pre-existing conditions. The overall case fatality rate among severity cases was 21.0%, and it differed according to age: 5.6% (n = 8/142) in the younger group, 28.1% in the older group, and 38% in the ≥ 65 years group. Age (odds ratio [OR], 7.902; 95% confidence interval [CI], 2.754–18.181), mechanical ventilation therapy (OR, 17.233; 95% CI, 8.439–35.192), highest creatinine > 1.5 mg/dL (OR, 17.631; 95% CI, 8.321–37.357), and combined blood stream infection (OR, 7.092;95% CI, 1.061–18.181) were identified as independent predictors of mortality in total patients.Similar patterns were observed in age-specific analyses, but most results were statistically insignificant in multivariate analysis due to the low number of deaths in the younger group.The full vaccination rate was very low among study population (13.6%), and only three patients were fully vaccinated, with none of the patients who died having been fully vaccinated in the younger group. Seven of eight patients who died had a pre-existing condition or were obese (BMI > 25 kg/m 2 ), and the one remaining patient died from a secondary infection. Conclusion About 22% of the patients in the young critical group did not have an underlying disease or obesity, but the rate of obesity (BMI > 25 kg/m2 ) was high, with a fatality rate of 5.6%. The full vaccination rate was extremely low compared to the general population of the same age group, showing that non-vaccination has a grave impact on the progression of COVID-19 to a critical condition. The findings of this study highlight the need for measures to prevent critical progression of COVID-19, such as vaccinations and targeting young adults especially having risk factors.

Background: Coronavirus disease 2019 (COVID-19) is often accompanied by secondary infections, such as invasive aspergillosis. In this study, risk factors for developing COVID-19-associated pulmonary aspergillosis (CAPA) and their clinical outcomes were evaluated. Methods: This multicenter retrospective cohort study included critically ill COVID-19 patients from July 2020 through March 2021. Critically ill patients were defined as patients requiring high-flow respiratory support or mechanical ventilation. CAPA was defined based on the 2020 European Confederation of Medical Mycology and the International Society for Human and Animal Mycology consensus criteria. Factors associated with CAPA were analyzed, and their clinical outcomes were adjusted by a propensity score-matched model. Results: Among 187 eligible patients, 17 (9.1%) developed CAPA, which is equal to 33.10 per 10,000 patient-days. Sixteen patients received voriconazole-based antifungal treatment. In addition, 82.4% and 53.5% of patients with CAPA and without CAPA, respectively, received early high-dose corticosteroids (P = 0.022). In multivariable analysis, initial 10-day cumulative steroid dose > 60 mg of dexamethasone or dexamethasone equivalent dose) (adjusted odds ratio [OR], 3.77; 95% confidence interval [CI], 1.03–13.79) and chronic pulmonary disease (adjusted OR, 4.20; 95% CI, 1.26–14.02) were independently associated with CAPA. Tendencies of higher 90-day overall mortality (54.3% vs. 35.2%, P= 0.346) and lower respiratory support-free rate were observed in patients with CAPA (76.3% vs. 54.9%, P = 0.089). Conclusion Our study showed that the dose of corticosteroid use might be a risk factor for CAPA development and the possibility of CAPA contributing to adverse outcomes in critically ill COVID-19 patients.

Background: Securing an available healthcare workforce is critical to respond to coronavirus disease 2019 (COVID-19); however, research investigating Korea’s COVID-19 staffing response is rare. To present the fundamental data of healthcare staff in response to the surge in COVID-19 cases, we investigated the healthcare workforce response in Daegu, South Korea, which experienced the first largest outbreak of COVID-19 outside of China. Materials and Methods: In response to the COVID-19 outbreak, this retrospective crosssectional study analyzed data on the scale and characteristics of healthcare workers (HCWs). Additionally, it analyzed the clinical and epidemiological characteristics of HCWs infected with COVID-19 in six major teaching hospitals (five tertiary and one secondary) in Daegu from January 19 to April 30, 2020. Results: During this study period, only 1.3% (n = 611) of the total hospitalized patients (n = 48,807) were COVID-19 inpatients, but they occupied 6.0% (n = 303) of the total hospital beds (n = 5,056), and 23.7% (n = 3,471) of all HCWs (n = 14,651) worked in response to COVID-19.HCWs participating in COVID-19-related works comprised 50.6% (n = 1,203) of doctors (n = 2,379), 26.3% (n = 1,571) of nurses (n = 5,982), and 11.4% (n = 697) of other HCWs (n = 6,108).Only 0.3% (n = 51) of HCWs (n = 14,651) developed COVID-19 infections from communityacquired (66.7%) or hospital-acquired (29.4%). Nurses were affected predominantly (33.3%), followed by doctors (9.8%), caregivers (7.8%), radiographers (5.9%), and others (45.1%), including nurse aides and administrative, facility maintenance, telephone appointment centers, and convenience store staff. All HCWs infected with COVID-19 recovered completely. The 32.7% (n = 333) of individuals (n = 1,018) exposed to HCWs who had COVID-19 were quarantined, and only one case of secondary transmission among them occurred. Conclusion The COVID-19 pandemic has necessitated significant staffing and facility usage, which is disproportionate to the relatively low number of COVID-19 inpatients, imposing a substantial burden on healthcare resources. Therefore, beyond the current reimbursement level of the Korean National Health Insurance, a new type of rewarding system is needed to prepare hospitals for the emerging outbreaks of infectious diseases. Keeping HCWs safe from COVID-19 is crucial for maintaining the healthcare workforce during a sudden massive outbreak. Further studies are needed to determine the standards of required HCWs through detailed research on the working hours and intensity of HCWs responding to COVID-19.

Coronavirus disease 2019 (COVID-19) is a global pandemic that had affected more than eight million people worldwide by June 2020. Given the importance of the presence of diabetes mellitus (DM) for host immunity, we retrospectively evaluated the clinical characteristics and outcomes of moderate-to-severe COVID-19 in patients with diabetes.

Background: The mortality risk of coronavirus disease 2019 (COVID-19) is higher in patients with older age, and many elderly patients are reported to require advanced respiratory support. Methods: We reviewed medical records of 98 patients aged ≥ 65 years who were hospitalized with COVID-19 during a regional outbreak in Daegu/Gyeongsangbuk-do province of Korea. The outcome measures were in-hospital mortality and the treatment with mechanical ventilation (MV) or high-flow nasal cannula (HFNC). Results: The median age of the patients was 72 years; 55.1% were female. Most (74.5%) had at least one underlying condition. Overall case fatality rate (CFR) was 20.4%, and median time to death after admission was 8 days. The CFR was 6.1% among patients aged 65–69 years, 22.7% among those aged 70–79 years, and 38.1% among those aged ≥ 80 years. The CFR among patients who required MV was 43.8%, and the proportion of patients received MV/HFNC was 28.6%. Nosocomial acquisition, diabetes, chronic lung diseases, and chronic neurologic diseases were significant risk factors for both death and MV/HFNC. Hypotension, hypoxia, and altered mental status on admission were also associated with poor outcome. CRP > 8.0 mg/dL was strongly associated with MV/HFNC (odds ratio, 26.31; 95% confidence interval, 7.78–88.92; P < 0.001), and showed better diagnostic characteristics compared to commonly used clinical scores. Conclusion Patients aged ≥ 80 years had a high risk of requiring MV/HFNC, and mortality among those severe patients was very high. Severe initial presentation and laboratory abnormalities, especially high CRP, were identified as risk factors for mortality and severe hospital course.

Background: s: The severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has spread worldwide. Cardiac injury after SARS-CoV-2 infection is a major concern. The present study investigated impact of the biomarkers indicating cardiac injury in coronavirus disease 2019 (COVID-19) on patients' outcomes. Methods: This study enrolled patients who were confirmed to have COVID-19 and admitted at a tertiary university referral hospital between February 19, 2020 and March 15, 2020. Cardiac injury was defined as an abnormality in one of the following result markers: 1) myocardial damage marker (creatine kinase-MB or troponin-I), 2) heart failure marker (N-terminal-pro B-type natriuretic peptide), and 3) electrical abnormality marker (electrocardiography). The relationship between each cardiac injury marker and mortality was evaluated. Survival analysis of mortality according to the scoring by numbers of cardiac injury markers was also performed. Results: A total of 38 patients with COVID-19 were enrolled. Twenty-two patients (57.9%) had at least one of cardiac injury markers. The patients with cardiac injuries were older (69.6 ± 14.9 vs. 58.6 ± 13.9 years old, P = 0.026), and were more male (59.1% vs. 18.8%, P = 0.013).They showed lower initial oxygen saturation (92.8 vs. 97.1%, P = 0.002) and a trend toward higher mortality (27.3 vs. 6.3%, P = 0.099). The increased number of cardiac injury markers was significantly related to a higher incidence of in-hospital mortality which was also evidenced by Kaplan-Meier survival analysis (P = 0.008). Conclusion The increased number of cardiac injury markers is related to in-hospital mortality in patients with COVID-19.

About 30~50% COVID-19 hospital inpatients is reported to have mild clinical presentation, and the clinical course is known to be good even in the older population. In order to compare the clinical symptoms of mild patients with COVID-19 infection by age, the clinical symptoms and laboratory results were analyzed by dividing mild patients admitted to a dedicated hospital into three groups: under the age of 64, 65-84, and above 85 years of age.There was no difference in gender ratio by age among 555 mild cases. Concomitant diseases with significant differences by age were hypertension, diabetes, stroke, and coronary artery disease.Among the symptoms, cough and sore throat were different by age, and cough was significantly higher in the group under 64 years of age. Among the symptoms, cough and sore throat were different by age, and cough was significantly higher in the group under 64 years of age.The white blood cell count (WBC), neutrophil count, monocyte, blood sugar, procalcitonin, and creatinine were significantly higher in the 85 years old or older group, and the hemoglobin, albumin, and glomerular filtration rate (GFR) were significantly lower in the 85 years old or older group.