Antimicrobial Use and Carbapenem-Resistant Enterobacterales in Korea: A Nationwide Case-Control Study With Propensity Score Matching.

BACKGROUND: Nationwide research on the association between carbapenem-resistant Enterobacterales (CREs) and antibiotic use is limited. METHODS: This nested case-control study analyzed Korean National Health Insurance claims data from April 2017 to April 2019. Based on the occurrence of CRE, hospitalized patients aged ≥ 18 years were classified into CRE (cases) and control groups. Propensity scores based on age, sex, modified Charlson comorbidity score, insurance type, long-term care facility, intensive care unit stay, and acquisition of vancomycin-resistant Enterococci were used to match the case and control groups (1:3). RESULTS: After matching, the study included 6,476 participants (1,619 cases and 4,857 controls). Multivariable logistic regression analysis revealed that the utilization of broad-spectrum antibiotics, such as piperacillin/tazobactam (adjusted odds ratio [aOR], 2.178; 95% confidence interval [CI], 1.829-2.594), third/fourth generation cephalosporins (aOR, 1.764; 95% CI, 1.514-2.056), and carbapenems (aOR, 1.775; 95% CI, 1.454-2.165), as well as the presence of comorbidities (diabetes [aOR, 1.237; 95% CI, 1.061-1.443], hemiplegia or paraplegia [aOR, 1.370; 95% CI, 1.119-1.679], kidney disease [aOR, 1.312; 95% CI, 1.105-1.559], and liver disease [aOR, 1.431; 95% CI, 1.073-1.908]), were significantly associated with the development of CRE. Additionally, the CRE group had higher mortality (8.33 vs. 3.32 incidence rate per 100 person-months, P < 0.001) and a total cost of healthcare utilization per person-month (15,325,491 ± 23,587,378 vs. 5,263,373 ± 14,070,118 KRW, P < 0.001) than the control group. CONCLUSION: The utilization of broad-spectrum antibiotics and the presence of comorbidities are associated with increasing development of CRE. This study emphasizes the importance of antimicrobial stewardship in reducing broad-spectrum antibiotic use and CRE disease burden in Korea.

Prevalence and Associated Factors of Depression and Anxiety Among Healthcare Workers During the Coronavirus Disease 2019 Pandemic: A Nationwide Study in Korea.

BACKGROUND: A healthcare system's collapse due to a pandemic, such as the coronavirus disease 2019 (COVID-19), can expose healthcare workers (HCWs) to various mental health problems. This study aimed to investigate the impact of the COVID-19 pandemic on the depression and anxiety of HCWs. METHODS: A nationwide questionnaire-based survey was conducted on HCWs who worked in healthcare facilities and public health centers in Korea in December 2020. Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to measure depression and anxiety. To investigate factors associated with depression and anxiety, stepwise multiple logistic regression analysis was performed. RESULTS: A total of 1,425 participating HCWs were included. The mean depression score (PHQ-9) of HCWs before and after COVID-19 increased from 2.37 to 5.39, and the mean anxiety score (GAD-7) increased from 1.41 to 3.41. The proportion of HCWs with moderate to severe depression (PHQ-9 ≥ 10) increased from 3.8% before COVID-19 to 19.5% after COVID-19, whereas that of HCWs with moderate to severe anxiety (GAD-7 ≥ 10) increased from 2.0% to 10.1%. In our study, insomnia, chronic fatigue symptoms and physical symptoms after COVID-19, anxiety score (GAD-7) after COVID-19, living alone, and exhaustion were positively correlated with depression. Furthermore, post-traumatic stress symptoms, stress score (Global Assessment of Recent Stress), depression score (PHQ-9) after COVID-19, and exhaustion were positively correlated with anxiety. CONCLUSION: In Korea, during the COVID-19 pandemic, HCWs commonly suffered from mental health problems, including depression and anxiety. Regularly checking the physical and mental health problems of HCWs during the COVID-19 pandemic is crucial, and social support and strategy are needed to reduce the heavy workload and psychological distress of HCWs.

Clinical utility of quantitative immunoassays and surrogate virus neutralization tests for predicting neutralizing activity against the SARS-CoV-2 Omicron BA.1 and BA.5 variants.

Developing new antibody assays for emerging SARS-CoV-2 variants is challenging. SARS-CoV-2 surrogate virus neutralization tests (sVNT) targeting Omicron BA.1 and BA.5 have been devised, but their performance needs to be validated in comparison with quantitative immunoassays. First, using 1749 PRNT-positive sera, we noticed that log-transformed optical density (OD) ratio of wild-type (WT) sVNT exhibited better titer-correlation with plaque reduction neutralization test (PRNT) than % inhibition value. Second, we tried 798 dilutional titration tests with 103 sera, but nonlinear correlation between OD ratio and antibody concentration limited titration of sVNT. Third, the titer-correlations of two sVNT kits for BA.1 and two quantitative immunoassays for WT were evaluated with BA.1 and BA.5 PRNT. All tested kits exhibited a linear correlation with PRNT titers, but the sVNT kits exhibited high false-negative rates (cPass-BA.1 kit, 45.4% for BA.1 and 44.2% for BA.5; STANDARD F-BA.1 kit, 1.9% for BA.1 and 2.2% for BA.5), while quantitative immunoassays showed 100% sensitivity. Linear mixed-effects model suggested superior titer-correlation with PRNT for quantitative immunoassays compared to sVNT kits. Taken together, the use of quantitative immunoassays for WT, rather than rapid development of new kits, would be practical for predicting neutralizing activities against emerging new variants.

Multiple heteroresistance to tigecycline and colistin in Acinetobacter baumannii isolates and its implications for combined antibiotic treatment.

BACKGROUND: We investigated the presence of heteroresistance against both tigecycline and colistin in Acinetobacter baumannii and then evaluated the effectiveness of combined antibiotic treatment given the existence of discrete tigecycline- and colistin-resistant subpopulations. METHODS: We performed population analysis profiling (PAP) to evaluate the degree of composite heteroresistance in A. baumannii isolates, with the extent of this resistance quantified using subsequent antibiotic susceptibility testing. We then evaluated the amino acid sequence of PmrBAC and the relative mRNA expression levels of pmrB. Finally, we investigated the combined antibiotic efficacy of tigecycline and colistin in multiple-heteroresistant isolates using dual PAP and in vitro time-killing assays. RESULTS: All tigecycline-heteroresistant A. baumannii isolates, with the exception of one colistin-resistant isolate, were also heteroresistant to colistin. Evaluations of the colistin-resistant subpopulations revealed amino acid alterations in PmrA and PmrB and increased expression of pmrB. All tigecycline-resistant subpopulations were susceptible to colistin, and all colistin-resistant subpopulations were susceptible to tigecycline. Dual PAP analysis using tigecycline and colistin showed no heteroresistance, and in vitro time-killing assays revealed that a combination of these two antibiotics effectively eliminated the bacterial cells. CONCLUSION: Our results suggest that multiple heteroresistance to tigecycline and colistin is highly prevalent among A. baumannii clinical isolates and that these resistant subpopulations exist independently in single multiple heteroresistant isolates. Therefore, our findings may explain the success of combined antibiotic therapies in these infections.

First Case of Pseudoclavibacter alba Bacteremia in a Patient with Cholangitis.

BACKGROUND: Pseudoclavibacter alba isolated from human urine in culture collection was introduced as a new species, but since then, no other reports on P. alba isolated from the environment or organisms have been published. We thus present the first case report of P. alba bacteremia. METHODS: An 85-year-old female patient was admitted with intermittent abdominal pain and chills that had persisted for one week. She was diagnosed cholangitis with common bile duct stones. RESULTS: Gram-positive bacteria were detected in her peripheral blood culture and identified Pseudoclavibacter species by matrix-assisted laser desorption-ionization-time of flight mass spectrometry. Pseudoclavibacter alba was identified by performing the 16S ribosomal RNA gene sequence. CONCLUSIONS: This is the first case report of P. alba bacteremia in a patient with cholangitis.

Incidence and Distribution of the Pathogens Causing GI Infections at a University Hospital of Korea.

BACKGROUND: Gastrointestinal (GI) infections, caused by various pathogens such as bacteria, viruses, protozoa, and parasites, are the second most common infectious diseases. Molecular diagnostics that can simultaneously detect these pathogens are commonly used in syndromic approaches. The authors aimed to identify the causative pathogens of GI infections to provide clinically useful information. METHODS: This retrospective study used molecular diagnostic methods to determine the incidence and distribution of GI pathogens according to gender, age, and season and analyze their coinfection from August 2020 to December 2022. RESULTS: The overall incidence of at least one GI pathogen was 40.1% (991/2, 471). The positivity rates for bacteria and viruses were 33.1% (817/2, 471) and 9.2% (227/2,471), respectively; the positivity rate for bacteria was significantly higher than that for viruses (p < 0.001). The incidence of GI pathogens according to age group was highest in group 3 (59.9%), followed by group 4 (57.0%). The most common bacterial pathogen associated with GI infections was C. difficile, followed by diarrheagenic E. coli, Campylobacter spp., and Salmonella spp. Enteropathogenic E. coli accounted for a large percentage of diarrheagenic E. coli (63.6%, 157/247). Among the viral pathogens, norovirus GI/GII was the most commonly detected virus, followed by adenovirus F40/41 and rotavirus A. For bacterial- or viral-positive cases, the distribution of GI pathogens according to age group showed the highest proportion of C. difficile in all groups, except for group 2. In group 2, rotavirus A accounted for the highest percentage (61.1%, 22/36). The incidence of GI pathogens was the highest in summer (36.1%), followed by autumn (32.7%), and winter (18.0%). The co-infection rate with two or more pathogens was 16.9% (167/991). The rates of co-infection with two or more bacteria, bacteria and viruses, and two viruses were 58.1%, 31.7%, and 10.2%, re-spectively. CONCLUSIONS: Information on the incidence and distribution of GI pathogens might be clinically useful; however, unlike the distribution of other infectious pathogens, it is necessary to consider that microorganisms identified through molecular diagnostics can be detected even in healthy people without clinical symptoms.

Use of Antibiotics Within the Last 14 Days of Life in Korean Patients: A Nationwide Study.

BACKGROUND: Antimicrobial prescriptions for serious chronic or acute illness nearing its end stages raise concerns about the potential for futile use, adverse events, increased multidrug-resistant organisms, and significant patient and social cost burdens. This study investigated the nationwide situation of how antibiotics are prescribed to patients during the last 14 days of life to guide future actions. METHODS: This nationwide multicenter retrospective cohort study was conducted at 13 hospitals in South Korea from November 1 to December 31, 2018. All decedents were included in the study. Antibiotic use during the last two weeks of their lives was investigated. RESULTS: A total of 1,201 (88.9%) patients received a median of two antimicrobial agents during the last two weeks of their lives. Carbapenems were prescribed to approximately half of the patients (44.4%) in the highest amount (301.2 days of therapy per 1,000 patient-days). Among the patients receiving antimicrobial agents, 63.6% were inappropriate and only 327 patients (27.2%) were referred by infectious disease specialists. The use of carbapenem (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.13-2.03; P = 0.006), underlying cancer (OR, 1.56; 95% CI, 1.20-2.01, P = 0.047), underlying cerebrovascular disease (OR, 1.88; 95% CI, 1.23-2.89, P = 0.004), and no microbiological testing (OR, 1.79; 95% CI, 1.15-2.73; P = 0.010) were independent predictors for inappropriate antibiotic prescribing. CONCLUSION: A considerable number of antimicrobial agents are administered to patients with chronic or acute illnesses nearing their end-of-life, a high proportion of which are prescribed inappropriately. Consultation with an infectious disease specialist, in addition to an antimicrobial stewardship program, may be necessary to induce the optimal use of antibiotics.

Post-acute COVID-19 syndrome in patients after 12 months from COVID-19 infection in Korea.

BACKGROUND: As the coronavirus disease 2019 (COVID-19) pandemic continues to progress, awareness about its long-term impacts has been growing. To date, studies on the long-term course of symptoms, factors associated with persistent symptoms, and quality of life after 12 months since recovery from acute COVID-19 have been limited. METHODS: A prospective online survey (First: September 8, 2020-September 10, 2020; Second: May 26, 2021-June 1, 2021) was conducted on recovered patients who were previously diagnosed with COVID-19 between February 13, 2020 and March 13, 2020 at Kyungpook National University Hospital. Responders aged between 17 and 70 years were included in the study. Overall, 900 and 241 responders were followed up at 6 and 12 months after recovery from COVID-19 in the first and second surveys, respectively. Clinical characteristics, self-reported persistent symptoms, and EuroQol-5-dimension (EQ5D) index score were investigated for evaluating quality of life. RESULTS: The median period from the date of the first symptom onset or COVID-19 diagnosis to the time of the survey was 454 (interquartile range [IQR] 451-458) days. The median age of the responders was 37 (IQR 26.0-51.0) years, and 164 (68.0%) responders were women. Altogether, 11 (4.6%) responders were asymptomatic, and 194 (80.5%), 30 (12.4%), and 6 (2.5%) responders had mild, moderate, and severe illness, respectively. Overall, 127 (52.7%) responders still experienced COVID-19-related persistent symptoms and 12 (5.0%) were receiving outpatient treatment for such symptoms. The main symptoms were difficulty in concentration, cognitive dysfunction, amnesia, depression, fatigue, and anxiety. Considering the EQ5D index scores, only 59.3% of the responders did not have anxiety or depression. Older age, female sex, and disease severity were identified as risk factors for persistent neuropsychiatric symptoms. CONCLUSION: COVID-19-related persistent symptoms improved over time; however, neurological symptoms can last longer than other symptoms. Continuous careful observation of symptom improvement and multidisciplinary integrated research on recovered COVID-19 patients are required.

Relationship between the appropriateness of antibiotic treatment and clinical outcomes/medical costs of patients with community-acquired acute pyelonephritis: a multicenter prospective cohort study.

BACKGROUND: Inappropriate use of antibiotics not only increases antibiotic resistance as collateral damage but also increases clinical failure rates and medical costs. The purpose of this study was to determine the relationship between the appropriateness of antibiotic prescription and outcomes of community-acquired acute pyelonephritis (CA-APN). METHODS: A multicenter prospective cohort study was conducted at eight hospitals in Korea between September 2017 and August 2018. All hospitalized patients aged ≥ 19 years who were diagnosed with CA-APN on admission were recruited. The appropriateness of empirical and definitive antibiotics, as well as the appropriateness of antibiotic treatment duration and route of administration, was evaluated in accordance with the guideline and expert opinions. Clinical outcomes and medical costs were compared between patients who were administered antibiotics 'appropriately' and 'inappropriately.' RESULTS: A total of 397 and 318 patients were eligible for the analysis of the appropriateness of empirical and definitive antibiotics, respectively. Of them, 10 (2.5%) and 18 (5.7%) were administered 'inappropriately' empirical and definitive antibiotics, respectively. Of the 119 patients whose use of both empirical and definitive antibiotics was classified as 'optimal,' 57 (47.9%) received antibiotics over a longer duration than that recommended; 67 (56.3%) did not change to oral antibiotics on day 7 of hospitalization, even after stabilization of the clinical symptoms. Patients who were administered empirical antibiotics 'appropriately' had shorter hospitalization days (8 vs. 10 days, P = 0.001) and lower medical costs (2381.9 vs. 3235.9 USD, P = 0.002) than those who were administered them 'inappropriately.' Similar findings were observed for patients administered both empirical and definitive antibiotics 'appropriately' and those administered either empirical or definitive antibiotics 'inappropriately'. CONCLUSIONS: Appropriate use of antibiotics leads to better outcomes, including reduced hospitalization duration and medical costs.

Beta-Lactam Plus Macrolide for Patients Hospitalized With Community-Acquired Pneumonia: Difference Between Autumn and Spring.

BACKGROUND: The 2017 Korean guideline on community-acquired pneumonia (CAP) recommended beta-lactam plus macrolide combination therapy for patients hospitalized with severe pneumonia, and beta-lactam monotherapy for mild-to-moderate pneumonia. However, antibiotic treatment regimen for mild-to-moderate CAP has never been evaluated for Korean patients. METHODS: In this retrospective cohort study, study patients were selected from three evaluation periods (October 1 to December 31, 2014; April 1 to June 30, 2016; October 1 to December 31, 2017) of the National Quality Assessment Program for CAP management and the National Health Insurance data on the selected patients was extracted from 1 year before the first patient enrollment and 1 year after the last patient enrollment at each evaluation period for the analysis of risk adjustment and outcomes. The survival rates between beta-lactam plus macrolide (BM) groups and beta-lactam monotherapy (B) were compared using a Kaplan-Meier survival analysis after propensity score matching by age, gender, confusion, urea, respiratory rate, blood pressure at age of 65 years or older (CURB-65), and Charlson comorbidity index for risk adjustment. The differences between autumn and spring season were also evaluated. RESULTS: A total of 30,053 patients were enrolled. Mean age and the male-to-female ratio were 64.7 ± 18.4 and 14,197:15,856, respectively. After matching, 2,397 patients in each group were analyzed. The 30-day survival rates did not differ between the BM and B groups (97.3% vs. 96.5%, P = 0.081). In patients with CURB-65 ≥ 2, the 30-day survival rate was higher in the BM than in the B group (93.7% vs. 91.0%, P = 0.044). Among patients with CURB-65 ≥ 2, the 30-day survival rate was higher in the BM than in the B group (93.3% vs. 88.5%, P = 0.009) during autumn season, which was not observed during spring (94.2% vs. 94.1%, P = 0.986). CONCLUSION: Beta-lactam plus macrolide combination therapy shows potential as an empirical therapy for CAP with CURB-65 ≥ 2, especially in autumn.

Workload of Healthcare Workers During the COVID-19 Outbreak in Korea: A Nationwide Survey.

BACKGROUND: As the coronavirus disease 2019 (COVID-19) pandemic is ongoing, heavy workload of healthcare workers (HCWs) is a concern. This study investigated the workload of HCWs responding to the COVID-19 outbreak in South Korea. METHODS: A nationwide cross-sectional survey was conducted from September 16 to October 15, 2020, involving 16 healthcare facilities (4 public medical centers, 12 tertiary-care hospitals) that provide treatment for COVID-19 patients. RESULTS: Public medical centers provided the majority (69.4%) of total hospital beds for COVID-19 patients (n = 611), on the other hand, tertiary care hospitals provided the majority (78.9%) of critical care beds (n = 57). The number of beds per doctor (median [IQR]) in public medical centers was higher than in tertiary care hospitals (20.2 [13.0, 29.4] versus 3.0 [1.3, 6.6], P = 0.006). Infectious Diseases physicians are mostly (80%) involved among attending physicians. The number of nurses per patient (median [interquartile range, IQR]) in tertiary-care hospitals was higher than in public medical centers (4.6 [3.4-5] vs. 1.1 [0.8-2.1], P = 0.089). The median number of nurses per patient for COVID-19 patients was higher than the highest national standard in South Korea (3.8 vs. 2 for critical care). All participating healthcare facilities were also operating screening centers, for which a median of 2 doctors, 5 nurses, and 2 administrating staff were necessary. CONCLUSION: As the severity of COVID-19 patients increases, the number of HCWs required increases. Because the workload of HCWs responding to the COVID-19 outbreak is much greater than other situations, a workforce management plan regarding this perspective is required to prevent burnout of HCWs.

Clinical outcomes and healthcare costs of inpatients with tetanus in Korea, 2011-2019.

BACKGROUND: Tetanus is a rare, vaccine-preventable but extremely serious disease. We investigated the recent trend of the clinical outcomes and medical costs for inpatients with tetanus in South Korea over 10 years. METHODS: We conducted a retrospective review to determine the clinical factors and medical costs associated with tetanus at two national university hospitals in South Korea between January 2011 and October 2019. RESULTS: Forty-nine patients were admitted for tetanus (mean age, 67.0 years [range, 53.0-80.0 years]; 32 women [57.1%]). All the patients had generalized tetanus, and 5 (10.2%) died during hospitalization. The median duration from symptom onset to hospital admission was 4 days. Trismus (85.7%) was the most common symptom, and the median hospital stay was 39 days. Thirty-two patients (65.3%) required mechanical ventilation, and 20 (40.8%) developed aspiration pneumonia. The median total healthcare cost per patient was US $18,011. After discharge, 35 patients (71.4%) recovered sufficiently to walk without disability. CONCLUSIONS: Tetanus requires long hospital stays and high medical expenditures in South Korea; however, the vaccination completion rate is low. Medical staff should therefore promote medical advice and policies on the management of tetanus to the general South Korean population.

Comparison of the clinical characteristics of community-acquired acute pyelonephritis between male and female patients.

BACKGROUND: Community-acquired acute pyelonephritis (CA-APN) is relatively rare in men. This study aimed to compare the clinical characteristics of CA-APN between male and female patients. METHODS: We prospectively collected the clinical and microbiological data of hospitalized CA-APN patients aged ≥19 years in South Korea from March 2010 to February 2011 in 11 hospitals and from September 2017 to August 2018 in 8 hospitals. Only the first episodes of APN of each patient during the study period were included. RESULTS: From 2010 to 2011, 573 patients from 11 hospitals were recruited, and from 2017 to 2018, 340 patients were recruited from 8 hospitals. Among them, 5.9% (54/913) were male. Male patients were older (66.0 ± 15.2 vs. 55.3 ± 19.0 years, P < 0.001), had a higher Charlson comorbidity index (1.3 ± 1.5 vs. 0.7 ± 1.2, P = 0.027), and had a higher proportion of structural problems in the urinary tract (40.7% vs. 6.1%, P < 0.001) than female patients. Moreover, the total duration of antibiotic treatment was longer (21.8 ± 17.8 d vs. 17.3 ± 9.4 d, P = 0.001) and the proportion of carbapenem usage was higher (24.1% vs. 9.5%, P = 0.001) in men than in women. Male patients were hospitalized for longer durations than female patients (median, 10 d vs. 7 d, P < 0.001). CONCLUSIONS: Male CA-APN patients were older and had more comorbidities than female CA-APN patients. In addition, male patients received antibiotic treatment for a longer duration than female patients.

The Experiences of Health Care Workers during the COVID-19 Pandemic in Korea: a Qualitative Study.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, health care workers (HCWs) have faced multiple physical and psychological challenges while carrying out their duties. In this study, we examined the experiences of specific groups of HCWs during the pandemic. METHODS: From 18 November to 30 December 2020, we conducted a qualitative study using semi-structured, face-to-face interviews with four groups of 14 HCWs in three cities (Seoul, Daegu, and Gwangju) in South Korea. The HCWs who participated in the focus groups included physicians, nurses, medical practitioners, and cleaning staff who directly or indirectly cared for patients during the COVID-19 epidemic. Interviews were transcribed verbatim and analyzed using the consensual qualitative research approach. RESULTS: Our qualitative data analysis revealed four main domains: work-related struggles, personal life-related struggles, psychological stress, and health-related struggles. Health care providers were challenged by working in critical situations and were overwhelmed by heavy workloads, fear of infection, lifestyle changes, and psychological and physical struggles. CONCLUSION: Our findings could serve as a foundation for establishing health care systems and policies that help HCWs cope with occupational stress, thus increasing their ability to adapt to the ongoing COVID-19 pandemic.

Trends of Cause of Death among Human Immunodeficiency Virus Patients and the Impact of Low CD4 Counts on Diagnosis to Death: a Retrospective Cohort Study.

BACKGROUND: Monitoring the full spectrum of causes of death among human immunodeficiency virus (HIV) patients has become increasingly important as survival improves because of highly active antiretroviral therapy. However, there are no recently published data regarding the changes in the causes of death among HIV patients based on year of HIV diagnosis, and the impact of low CD4 count at the time of HIV diagnosis on the clinical outcome is still unclear in Korea. METHODS: A retrospective cohort study was conducted with 801 patients with HIV infection who were followed up at a tertiary university hospital and diagnosed with HIV between July 1984 and October 2019. The causes of death were analyzed by descriptive analysis based on CD4 count and the year of HIV diagnosis. Kaplan-Meier and log rank tests were performed to compare the prognosis between the CD4 < 200 cells/mm³ and CD4 ≥ 200 cells/mm³ groups. RESULTS: Among 801 patients, 67 patients were eligible for the death cause analysis. Infection-related death accounted for 44 patients (65.7%) and non-infection related death accounted for 23 patients (32.4%). Pneumocystis pneumonia (29.9%) was the single most common cause of death in both past and present cases, and tuberculosis (19.4%) was the second leading cause of death from infections, but the frequency has declined in recent years. Causes of infection-related death have decreased, whereas non-infection related causes of death have increased remarkably. Malignancy-related death was the most common cause of non-infection related death. Acquired immunodeficiency syndrome (AIDS) non-related malignancy accounted for 11.9%, whereas AIDS-related malignancy accounted for 6.0% of the total death among HIV patients. No significant statistical differences were found in mortality rate (P = 0.228), causes of death (P = 0.771), or survival analysis (P = 0.089) between the CD4 < 200 cells/mm³ and CD4 ≥ 200 cells/mm³ groups. CONCLUSION: Being diagnosed with CD4 < 200 cells/mm³ at the time of HIV diagnosis was not an indicator of greater risk of death compared with the CD4 ≥ 200 cells/mm³ group. Malignant tumors have become an important cause of death in recent years, and an increasing tendency of AIDS-non-related malignancy causes has been observed.

Drive-Through Screening Center for COVID-19: a Safe and Efficient Screening System against Massive Community Outbreak.

As the coronavirus disease 2019 (COVID-19) outbreak is ongoing, the number of individuals to be tested for COVID-19 is rapidly increasing. For safe and efficient screening for COVID-19, drive-through (DT) screening centers have been designed and implemented in Korea. Herein, we present the overall concept, advantages, and limitations of the COVID-19 DT screening centers. The steps of the DT centers include registration, examination, specimen collection, and instructions. The entire service takes about 10 minutes for one testee without leaving his or her cars. Increased testing capacity over 100 tests per day and prevention of cross-infection between testees in the waiting space are the major advantages, while protection of staff from the outdoor atmosphere is challenging. It could be implemented in other countries to cope with the global COVID-19 outbreak and transformed according to their own situations.

Development of Antibiotic Classification for Measuring Antibiotic Usage in Korean Hospitals Using a Modified Delphi Method.

In 2019, a project designed to develop a system for measuring and comparing antibiotic usage in hospitals was launched in Korea. As part of this project, we developed a means to classify antibiotic usage in Korean hospitals using a modified Delphi method. In results, the following categories of antibiotic classification were accepted for use in Korean hospitals: 1) broad-spectrum antibacterial agents predominantly used for hospital-onset infections in adults, 2) broad-spectrum antibacterial agents predominantly used for community-acquired infections in adults, 3) antibacterial agents predominantly used for resistant gram-positive infections in adults, 4) narrow-spectrum beta-lactam agents in adults, 5) antibacterial agents predominantly used for extensive antibiotic resistant gram-negative bacteria in adults, and 6) total antibacterial agents.

Significance of Decreasing Rate of HIV and HBV Co-infection in a Nationwide Korean HIV/AIDS Cohort.

From December 2006 to December 2016, 1093 human immunodeficiency virus (HIV) individuals < 70 years enrolled in Korea human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) cohort were analyzed to investigate the prevalence of HIV/HBV co-infection rate and hepatitis B virus surface antibody (HBsAb) positive rate based on birth year. The HBV co-infection prevalence rate was the highest (8.8%) in patients born between 1960 and 1964 and the lowest (0%) among those born between 1995 and 1999. A decreasing linear trend of HBV co-infection rate was observed according to the 5-year interval changes. HBsAb-positive rate was only 58.1% in our study. The national HBV vaccination programs have effectively lowered the HBV co-infection rate in HIV population. However, it is identified that the HIV population has low HBsAb positive rate. Further evidences supporting efficacy of booster immunization for HBsAb negative HIV patients are required and efforts should be made to increase HBsAb positive rates among HIV patients to prevent horizontal transmission.

A Prospective Cohort Study of Durations of Staphylococcus aureus Bacteremia According to Different Phenotypes and a New Concept of Persistent Bacteremia.

The purpose of this study was to describe and compare the duration of Staphylococcus aureus bacteremia (SAB) according to methicillin resistance and the primary foci of infection. We also aimed to newly define persistent SAB considering these results. Nonduplicated episodes of SAB in patients aged ≥15 years from 14 hospitals in the Republic of Korea were analyzed between January 2009 and February 2018. The duration of SAB was defined as the number of days from the time of administration of an antibiotic to which the isolate was susceptible after the onset of SAB to the last day of a positive blood culture for S. aureus SAB durations were described and compared based on methicillin resistance and the primary foci of infection. Cases in the top quartile for the duration of bacteremia in the respective clinical context were classified as newly defined persistent SAB, and its association with in-hospital mortality was evaluated. A total of 1,917 cases were analyzed. The duration of SAB was longer in patients with methicillin-resistant SAB (MRSAB; n = 995) than in patients with methicillin-susceptible SAB (MSSAB; n = 922) (median duration, 1 day [interquartile range, 1 to 3 days] for MSSAB and 1 day [interquartile range, 0 to 5 days] for MRSAB; P < 0.001). The duration of bacteremia was longer in patients with endocarditis and bone and joint, endovascular, and surgical site infections and was shorter in patients with skin and soft tissue infections. Newly defined persistent SAB was independently associated with in-hospital mortality (adjusted odds ratio, 1.97; 95% confidence interval, 1.54 to 2.53; P < 0.001). The durations of SAB were dependent on methicillin resistance and the primary foci of infection, and considering these contexts, persistent SAB was significantly associated with in-hospital mortality.

Significance of Increased Rapid Treatment from HIV Diagnosis to the First Antiretroviral Therapy in the Recent 20 Years and Its Implications: the Korea HIV/AIDS Cohort Study.

From December 2006 to December 2016, 1,429 patients enrolled in the Korea human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) Cohort Study were investigated. Based on the year of diagnosis, the time interval between HIV diagnosis and initiation of antiretroviral therapy (ART) was analyzed by dividing it into 2 years. The more recent the diagnosis, the more likely rapid treatment was initiated (P < 0.001) and the proportion of patients starting ART on the same day of HIV diagnosis was increased in 2016 (6.5%) compared to that in 2006 (1.7%). No significant difference in the median values of CD4+ cell counts according to the diagnosis year was observed. In the past 20 years, the time from the HIV diagnosis to the initiation of ART was significantly reduced. Rapid treatment was being implemented at the HIV diagnosis, regardless of CD4+ cell count. Considering the perspective "treatment is prevention," access to more rapid treatment is necessary at the time of HIV diagnosis.