Incidence of Clostridioides difficile Infections in Republic of Korea: A Prospective Study With Active Surveillance vs. National Data From Health Insurance Review & Assessment Service.

BACKGROUND: Since the emergence of hypervirulent strains of Clostridioides difficile, the incidence of C. difficile infections (CDI) has increased significantly. METHODS: To assess the incidence of CDI in Korea, we conducted a prospective multicentre observational study from October 2020 to October 2021. Additionally, we calculated the incidence of CDI from mass data obtained from the Health Insurance Review and Assessment Service (HIRA) from 2008 to 2020. RESULTS: In the prospective study with active surveillance, 30,212 patients had diarrhoea and 907 patients were diagnosed with CDI over 1,288,571 patient-days and 193,264 admissions in 18 participating hospitals during 3 months of study period; the CDI per 10,000 patient-days was 7.04 and the CDI per 1,000 admission was 4.69. The incidence of CDI was higher in general hospitals than in tertiary hospitals: 6.38 per 10,000 patient-days (range: 3.25-12.05) and 4.18 per 1,000 admissions (range: 1.92-8.59) in 11 tertiary hospitals, vs. 9.45 per 10,000 patient-days (range: 5.68-13.90) and 6.73 per 1,000 admissions (range: 3.18-15.85) in seven general hospitals. With regard to HIRA data, the incidence of CDI in all hospitals has been increasing over the 13-year-period: from 0.3 to 1.8 per 10,000 patient-days, 0.3 to 1.6 per 1,000 admissions, and 6.9 to 56.9 per 100,000 population, respectively. CONCLUSION: The incidence of CDI in Korea has been gradually increasing, and its recent value is as high as that in the United State and Europe. CDI is underestimated, particularly in general hospitals in Korea.

Is the fluoroquinolone combination necessary for empirical antibiotic regimen in severe community-acquired pneumonia?

OBJECTIVES: This study aimed to assess whether superior clinical outcomes can be attained through piperacillin/tazobactam (TZP)+fluoroquinolone (FQ) combination therapy for severe community-acquired pneumonia (CAP) compared to TZP monotherapy. METHODS: This retrospective study was conducted at a tertiary care hospital in Korea. Adult inpatients diagnosed with pneumonia within 48 hours of hospitalization were included. Severe CAP was defined as a CURB-65 score of ≥ 3 or based on the 2007 guidelines of the Infectious Diseases Society of America/American Thoracic Society (IDSA/ATS) definition. Only patients who received either TZP and FQ combination or TZP as initial empirical therapy were included. RESULTS: The final analysis included 145 patients; 57.9% received combination therapy and 42.1% received monotherapy. In the combination therapy group, body mass index (20.67 ± 3.28 vs. 22.26 ± 4.80, p = 0.030) and asthma prevalence (0 vs 8.3%, p = 0.022) were significantly higher; initial symptoms, clinical severity, and causative pathogens were not significantly different between groups. White blood cell counts (12,641.64 ± 6,544.66 vs. 12491.67 ± 10,528.24, p = 0.008), and C-reactive protein levels (18.78 ± 11.47 vs. 26.58 ± 14.97, p < 0.001) were significantly higher in the combination therapy group. Clinical outcomes, including all-cause in-hospital mortality rate (26.2 vs. 33.3%, p = 0.358), were not significantly different between the groups. Multivariate analysis identified no significant association between FQ combination and all-cause in-hospital mortality. CONCLUSION: In patients with severe CAP, there were no differences in the clinical outcomes, including mortality, between the TZP and FQ combination therapy and TZP monotherapy. FQ combination was not significantly associated with in-hospital mortality.

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 and microbiological characteristics of female patients with acute pyelonephritis who experienced urinary tract infections within the previous year.

BACKGROUND: This study aimed to examine the clinical and microbiological characteristics of female patients with recurrent acute pyelonephritis (APN). METHODS: A retrospective cohort study was conducted at a tertiary care hospital in South Korea from July 2019 to December 2021. All female patients aged ≥ 19 years who were diagnosed with community-acquired APN on admission were enrolled. The recurrent group included patients with APN who experienced urinary tract infections within the previous year. The clinical characteristics, types of causative organisms, major antibiotic resistance, and molecular characteristics of Escherichia coli strains were compared between the recurrent and non-recurrent groups. RESULTS: A total of 285 patients with APN were analyzed, including 41 (14.4%) in the recurrent group. Compared to the non-recurrent group, the recurrent group had a higher Charlson Comorbidity Index (1.8 ± 2.1 vs. 1.1 ± 1.5; P = 0.01) and a higher proportion of bladder abnormalities, such as neurogenic bladder (12.2% vs. 2.0%; P = 0.001) and urinary catheterization (12.2% vs. 1.6%; P < 0.001). Escherichia coli was the most common causative organism in both groups. The proportion of Klebsiella pneumoniae (17.1% vs. 4.7%; P = 0.007) and Pseudomonas aeruginosa (5.7% vs. 0.5%; P = 0.014) as a causative organism was higher in the recurrent group. Regarding the microbiological characteristics of Escherichia coli, there were no significant differences in the proportion of antibiotic resistance, phylogenetic groups, resistance genes, and virulence factors between the two groups. Multivariable analysis showed that neurogenic bladder and a history of admission or antibiotic use during 1 year prior to inclusion were significantly associated with recurrent APN. CONCLUSIONS: The proportion of causative organisms except Escherichia coli was higher in the recurrent group than in the non-recurrent group. Neurogenic bladder and a history of admission or antibiotic use during 1 year prior to inclusion were risk factors for recurrent APN.

Comparative analyses of the faecal resistome against ß-lactam and quinolone antibiotics in humans and livestock using metagenomic sequencing.

To assess the prevalence and abundance of antibiotic resistance genes in human and livestock gut microbiomes, 87 humans (healthy individuals and patients with Clostridioides difficile infection (CDI)) and 108 livestock (swine, cattle, and chickens) were enrolled. Gut microbiomes and fluoroquinolone-resistant Escherichia coli isolates were sequenced, and mobile genetic elements adjacent to the ß-lactamase (bla) and transferable quinolone resistance (qnr) genes were compared using metagenomic contigs. Each group of humans and livestock exhibited distinctive microbiota and resistome compositions in the gut. Concerning the resistome of bla and qnr, the prevalence rates between chickens and patients with CDI were the most similar (R2 = 0.46); blaTEM, blaOXA, blaCTX-M, and qnrS were highly prevalent in both groups. According to genomic and phylogenetic analyses, blaCTX-M and blaOXA expressed lineage specificity to either humans or livestock, while qnrS and blaTEM displayed a shared lineage between humans and livestock. A qnrS1 mobilome comprising five genes, including two recombinases, a transposase, and a plasmid gene, is commonly found in human and chicken gut microbiomes. Humans and chickens showed the most similar gut resistomes to ß-lactams and quinolones. QnrS and blaTEM displayed especially strong co-occurrence between the guts of humans and livestock.

Developing a framework for regular and sustainable qualitative assessment of antibiotic use in Korean medical institutions: a Delphi study.

BACKGROUND: We aimed to develop a roadmap for conducting regular, sustainable, and strategic qualitative assessments of antibiotic use in medical institutions within the Republic of Korea. METHODS: A literature review on the current state of qualitative antibiotic assessments was conducted, followed by one open round to collect ideas, two scoring rounds to establish consensus, and one panel meeting between them. The expert panel comprised 20 experts in infectious disease or antibiotic stewardship. RESULTS: The response rate for all three surveys was 95% (19/20), while the panel meeting attendance rate was 90% (18/20). The following long-term goals were defined to assess the annual use of antibacterial and antifungal agents in all medical institutions, including clinics. The panel agreed that random sampling of antibiotic prescriptions was the most suitable method of selecting antibiotics for qualitative assessment, with the additional possibility of evaluating specific antibiotics or infectious diseases that warrant closer evaluation for promoting appropriate antibiotic use. The plan for utilization of results from evaluation involves providing feedback while maintaining anonymity and disclosure. It includes a quantitative assessment of antibiotic prescriptions and resistance rates to compare against institutional benchmarks. Furthermore, it was agreed to link the evaluation findings to the national antibiotic stewardship programme, enabling policy and institutional approaches to address frequently misused items, identified during the evaluation. CONCLUSION: This study provides a framework for establishing a qualitative assessment of antimicrobial use for medical institutions at a national level in the Republic of Korea.

Risk of lymphadenopathy from SARS-CoV-2 vaccination in Korea: a self-controlled case series analysis.

OBJECTIVES: To assess the risk of lymphadenopathy following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. METHODS: A self-controlled case series design was used to determine whether the risk of lymphadenopathy was higher in the 1-day to 42-day risk interval after coronavirus disease 2019 (COVID-19) vaccination compared to the control period. In addition, subgroup analyses were conducted according to baseline characteristics, time since vaccination, and sensitivity analyses adjusted for the length of the risk interval. RESULTS: The risk of developing lymphadenopathy in the risk interval (1-42 days) after COVID-19 vaccination compared to the control period was significantly increased, with a relative incidence (RI) of 1.17 (95% confidence interval [CI], 1.17 to 1.18) when the first, second, and third doses were combined. The RI was greater on the day of vaccination (1.47; 95% CI, 1.44 to 1.50). In subgroup analyses by baseline characteristics, a significantly increased risk or trend toward increased risk was observed in most subgroups except for those aged 70 years and older, with a significant increase in risk in younger individuals, those with a Charlson's comorbidity index <5, and those who received mRNA vaccines (mRNA-1273>BNT162b2). Within the 1-day to 42-day post-dose risk period, the relative risk was highest during the 1-day to 7-day post-dose period (1.59; 95% CI, 1.57 to 1.60) compared to the control period, and then the risk declined. In the sensitivity analysis, we found that the longer the risk window, the smaller the RI. CONCLUSIONS: SARS-CoV-2 vaccination is associated with a statistically significant increase in the risk of lymphadenopathy, and this risk was observed only with mRNA vaccines.

Risk factors that are associated with adrenal insufficiency among patients with fever of unknown origin.

BACKGROUND: Adrenal insufficiency is one of the causes of fever of unknown origin (FUO). The purpose of this study is to find out risk factors that are associated with adrenal insufficiency in FUO patients. METHODS: This study was conducted retrospectively in a tertiary hospital with 846 beds in South Korea. All adult inpatients (age ≥19 years) who have requested a consult with the department of infectious disease for FUO between 1 July 20191 July 2019 and 30 June 202030 June 2020 were included in the study. Among them, those who underwent an adrenocorticotropic hormone (ACTH) stimulation test and had a fever of 37.8°C or higher within 48 hours of the ACTH stimulation test were finally included in the study subjects. RESULTS: A total of 202 FUO patients were enrolled and 61 (30.1%) were finally diagnosed with adrenal insufficiency. In a multivariate analysis, use of immunosuppressant within 3 months (OR 6.06, 95% CI 1.82-20.13, P = 0.003), use of corticosteroid within 3 months (OR 8.23, 95% CI 1.35-50.17, P = 0.022), sodium ≥ 136.7 (OR 3.43, 95% CI 1.49-7.88, P = 0.004), and calcium ≥ 8.4 (OR 0.31, 95% CI 0.14-0.71, P = 0.005) were proven to be factors associated with adrenal insufficiency in FUO patients. CONCLUSION: In conclusion, 30.1% of FUO patients were diagnosed with adrenal insufficiency. The risk factors that are associated with adrenal insufficiency in FUO patients were immunosuppressive prescription or systemic steroid prescription within 3 months, or with sodium ≥ 136.7 or calcium < 8.4.

Antibiotic Use during Pregnancy in South Korea Using 2011-2020 National Health Insurance Claims Data.

BACKGROUND: Since antimicrobial overuse and misuse can have substantial impacts on both public health and fetal well-being, it is essential to gain comprehensive insights into antimicrobial consumption patterns in pregnant women. This study aims to demonstrate antimicrobial utilization in pregnant women. METHODS: We conducted a population-based cohort study using National Health Insurance claims data from January 2009 to December 2020 in South Korea. The target population was pregnancies in women aged 15-45 years who gave birth between 2011 and 2019. The outcome measure was the percentage of antibiotic prescriptions by trimester, subgroup, diagnostic category, and therapeutic category. Antibiotics were defined as J01 in the WHO ATC/DDD classification. To analyze the factors that influenced antibiotic prescriptions, we conducted multivariate logistic regression analysis. RESULTS: Antibiotics were prescribed at least once in 1,808,588 (50%) of the 3,614,478 pregnancies. The proportion of deliveries with exposure to antibiotic therapy during pregnancy increased from 48% in 2011 to 54.8% in 2020. The prescription rate of antibiotics was highest in mothers younger than 25 years old, and it was lowest in participants aged 30-34 years. Also, antibiotic use was highest in the first trimester (30%) and lowest in the second trimester (18.2%). The most commonly used class was J01D (other beta-lactam antibacterials), which includes cephalosporins, and it accounted for 57% of the prescribed antibiotics. An increased probability of being prescribed antibiotics was associated with those younger than 25 years old, insurance (Medical Aid), hospitalization experience, an increase in physician visits, and comorbidities. For comorbidities, the OR was higher for respiratory tract infection (RTI), sexually transmitted infection, and urinary tract infection compared to those without disease, whereas it was decreased for diabetes and epilepsy. CONCLUSION: The prescribing rate of antibiotics to pregnant women in South Korea has remained stably high. Also, an increase in the use of broad-spectrum beta-lactam penicillin was noted. It is necessary to monitor antibiotics in pregnant women generally in accordance with recommendations.

Carbapenem Use in the Last Days of Life: A Nationwide Korean Study.

The appropriate use of carbapenem is a critical concern for patient safety and public health, and is a national priority. We investigated the nationwide status of carbapenem prescription in patients within their last 14 days of life to guide judicious-use protocols from the previous study comprised of 1350 decedents. Carbapenem use was universally controlled through computerised authorisation system at all centres during the study period. Carbapenem prescribing patterns and their optimality were evaluated. A total of 1201 patients received antimicrobial agents within the last two weeks of their lives, of whom 533 (44.4%) received at least one carbapenem. The median carbapenem treatment duration was seven days. Of the 533 patients receiving carbapenems, 510 (95.7%) patients had microbiological samples drawn and 196 (36.8%) yielded carbapenem-resistant pathogens. A total of 200 (37.5%) patients were referred to infectious disease (ID) specialists. Of the 333 patients (62.5%) who did not have ID consultations, 194 (58.2%) were assessed as "not optimal", 79 (23.7%) required escalation, 100 (30.0%) required de-escalation, and 15 (4.5%) were discontinued. Notwithstanding the existing antibiotic restriction program system, carbapenems are commonly prescribed to patients in their last days of life.

Developing Core Elements and Checklist Items for Implementing Antimicrobial Stewardship Programs in Korean General Hospitals: A Modified Delphi Survey.

BACKGROUND: Antimicrobial stewardship programs (ASPs) aim to optimize antimicrobial use by minimizing the spread of antimicrobial resistance. The core elements for implementing ASPs in healthcare facilities have been developed by the World Health Organization, international research group and government agencies of various countries. However, to date, there is no documented core elements for implementation of ASP in Korea. This survey aimed to establish a national consensus on a set of core elements and their related checklist items for the implementation of ASPs in Korean general hospitals. MATERIALS AND METHODS: The survey was conducted from July 2022 to August 2022 by the Korean Society for Antimicrobial Therapy with support from the Korea Disease Control and Prevention Agency. A literature review was conducted by searching Medline and relevant websites to retrieve a list of core elements and checklist items. These core elements and checklist items were evaluated by a multidisciplinary panel of experts using a structured modified Delphi consensus procedure, using two-step survey included online in-depth questionnaires and in-person meeting. RESULTS: The literature review identified 6 core elements (Leadership commitment, Operating system, Action, Tracking, Reporting, and Education) and 37 related checklist items. Fifteen experts participated in the consensus procedures. Ultimately, all 6 core elements were retained, and 28 checklist items were proposed, all with ≥80% agreement; in addition 9 items were merged into 2 items, 2 items were deleted, and 15 items were rephrased. CONCLUSION: This Delphi survey provides useful indicators for the implementation of ASP in Korea and suggests national policy improvement about the barriers (e.g., shortage of staffing and financial support) existing in Korea for optimal implementation of ASPs.

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.

Analysis of Changes in Antibiotic Use Patterns in Korean Hospitals during the COVID-19 Pandemic.

With the onset of the coronavirus disease 2019 (COVID-19) pandemic, changes in patient care and antibiotic use have occurred in hospitals. The data of the National Health Insurance System's claims of inpatients from all hospitals in Korea between January 2019 and December 2020 were obtained from the Health Insurance Review & Assessment Service and analyzed. The trend in the use of all antibacterial agents in both hospitals declined for the total number of COVID-19 patients at the bottom 10% and those in the top 10%. Specifically, a decreasing trend in the use of broad-spectrum antibacterial agents predominantly prescribed for community-acquired cases and narrow-spectrum beta-lactam agents were observed in both hospitals. In the aftermath of the COVID-19 pandemic, the total use of antibacterial agents has gradually decreased among patients with pneumonia and those with severe COVID-19. In contrast, its use has increased gradually among those with mild to moderate COVID-19. A decreasing trend in overall antibiotic use was observed during the COVID-19 pandemic, and an increasing trend in antibiotic use was observed in patients with mild to moderate COVID-19 in Korean hospitals.

Correlates of burnout among healthcare workers during the COVID-19 pandemic in South Korea.

Burnout is a form of negative emotional and physical response to job stress. This study aimed to investigate the prevalence of burnout among healthcare workers responding to the coronavirus disease 2019 (COVID-19) outbreak in Korea and to explore correlates of burnout among healthcare workers. A nationwide questionnaire-based survey was conducted from December 1, 2020, to January 29, 2021 on 1425 healthcare workers who worked in one of the 16 healthcare facilities designated for COVID-19 care, in public health centers, or as paramedics in Korea. Burnout was assessed using 16 Korean-adapted items based on the Oldenburg Burnout Inventory (OLBI). Data were collected using a structured questionnaire and analyzed using the R version 4.1.1 software program. OLBI results indicate clinically exhaustion in 84.5% (1204/1425) and clinically disengagement in 91.1% (1298/1425), and 77.3% (1102/1425) met the score criteria for both the exhaustion and disengagement subscales for burnout. Burnout rate was significantly increased in the group with chronic fatigue symptoms (Fatigue Severity Scale ≥ 3.22) after the outbreak of COVID-19 (OR, 3.94; 95% CI 2.80-5.56), in the female group (OR, 2.05; 95% CI 1.46-2.86), in the group with physical symptoms (Patient Health Questionnaire-15 ≥ 10) after the outbreak of COVID-19 (OR, 2.03; 95% CI 1.14-3.60), in the group with a higher Global Assessment of Recent Stress scale (OR, 1.71; 95% CI 1.46-2.01), in the group with post-traumatic stress symptoms (Primary Care Post-Traumatic Stress Disorder-5 ≥ 2) (OR, 1.47; 95% CI 1.08-2.01), and in the younger age group(OR, 1.45; 95% CI 1.22-1.72). The chronic fatigue symptoms were correlated with cumulative days of care (OR, 1.18; 95% CI 1.02-1.37). The physical symptoms were correlated with average contact hours with COVID-19 patients per day (OR, 1.34; 95% CI 1.17-1.54), and cumulative days of care (OR, 1.21; 95% CI 1.06-1.38). Most Korean healthcare workers suffered from burnout related to excessive workload during the COVID-19 pandemic. During a widespread health crisis like COVID-19, it is necessary to regularly check the burnout status in healthcare workers and reduce their excessive workload by supplementing the workforce and providing appropriate working hours sufficient rest hours.

Vaccine Effect on Household Transmission of Omicron and Delta SARS-CoV-2 Variants.

BACKGROUND: We evaluated the household secondary attack rate (SAR) of the omicron and delta severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, according to the vaccination status of the index case and household contacts; further, in vaccinated index cases, we evaluated the effect of the antibody levels on household transmission. METHODS: A prospective cross-sectional study of 92 index cases and 197 quarantined household contacts was performed. Tests for SARS-CoV-2 variant type and antibody level were conducted in index cases, and results of polymerase chain reaction tests (during the quarantine period) were collected from contacts. Association of antibody levels in vaccinated index cases and SAR was evaluated by multivariate regression analysis. RESULTS: The SAR was higher in households exposed to omicron variant (42%) than in those exposed to delta variant (27%) (P = 0.040). SAR was 35% and 23% for unvaccinated and vaccinated delta variant exposed contacts, respectively. SAR was 44% and 41% for unvaccinated and vaccinated omicron exposed contacts, respectively. Booster dose immunisation of contacts or vaccination of index cases reduced SAR of vaccinated omicron variant exposed contacts. In a model with adjustment, anti-receptor-binding domain antibody levels in vaccinated index cases were inversely correlated with household transmission of both delta and omicron variants. Neutralising antibody levels had a similar relationship. CONCLUSION: Immunisation of household members may help to mitigate the current pandemic.

Diversity of binary toxin positive Clostridioides difficile in Korea.

The objective of this study is to determine the trend and diversity of binary toxin-positive Clostridioides difficile over 10 years in Korea. Binary toxin-positive strains were selected from a tertiary hospital in Korea in 2009-2018. The multi-locus sequence typing and antibiotic susceptibility test were performed. Among the 3278 isolates in 2009-2018, 58 possessed binary toxin genes (1.7%). The proportion of CDT- positive isolates was 0.51-4.82% in 2009-2018, which increased over the 10-year period (P = 0.023). Thirteen sequence types (STs) were identified; ST5 (14 [24%]), ST11 (11 [19%]), ST221 (10 [17%]), ST201 (7 [12%]) and ST1 (5 [9%]) were popular. All 58 isolates were susceptible to vancomycin and piperacillin/tazobactam, and clindamycin and moxifloxacin were active in 69.0% and 62% of isolates, respectively. ST1 strains were resistant to several antibiotics, including moxifloxacin (80%), clindamycin (60%) and rifaximin (60%). Moreover, four of five ST1 presented a metronidazole minimum inhibitory concentration of 4 µg/mL. Moxifloxacin resistance was highest (72.3%) for ST11. In conclusion, binary toxin-positive strains are non-prevalent in Korea and involve diverse STs. ST1 strains were resistant to several antibiotics.

A study on changes in lung function, neutralizing antibodies, and symptoms of adult patients hospitalized with COVID-19.

BACKGROUND/AIMS: To identify changes in symptoms and pulmonary sequelae in patients with coronavirus disease 2019 (COVID-19). METHODS: Patients with COVID-19 hospitalized at seven university hospitals in Korea between February 2020 and February 2021 were enrolled, provided they had ≥ 1 outpatient follow-up visit. Between January 11 and March 9, 2021 (study period), residual symptom investigations, chest computed tomography (CT) scans, pulmonary function tests (PFT), and neutralizing antibody tests (NAb) were performed at the outpatient visit (cross-sectional design). Additionally, data from patients who already had follow-up outpatient visits before the study period were collected retrospectively. RESULTS: Investigation of residual symptoms, chest CT scans, PFT, and NAb were performed in 84, 35, 31, and 27 patients, respectively. After 6 months, chest discomfort and dyspnea persisted in 26.7% (4/15) and 33.3% (5/15) patients, respectively, and 40.0% (6/15) and 26.7% (4/15) patients experienced financial loss and emotional distress, respectively. When the ratio of later CT score to previous ones was calculated for each patient between three different time intervals (1-14, 15-60, and 61-365 days), the median values were 0.65 (the second interval to the first), 0.39 (the third to the second), and 0.20 (the third to the first), indicating that CT score decreases with time. In the high-severity group, the ratio was lower than in the low-severity group. CONCLUSION: In COVID-19 survivors, chest CT score recovers over time, but recovery is slower in severely ill patients. Subjects complained of various ongoing symptoms and socioeconomic problems for several months after recovery.

Professional Status of Infectious Disease Specialists in Korea: A Nationwide Survey.

BACKGROUND: Infectious disease (ID) specialists are skilled facilitators of medical consultation who promote better outcomes in patient survival, antibiotic stewardship as well as healthcare safety in pandemic response. This study aimed to assess the working status of ID specialists and identify problems faced by ID professionals in Korea. METHODS: This was a nationwide cross-sectional study in Korea. An online-based survey was conducted over 11 days (from December 17-27, 2020), targeting all active adult (n = 281) and pediatric (n = 71) ID specialists in Korea (N = 352). Questions regarding the practice areas of the specialists were divided into five categories: 1) clinical practices of outpatient care, inpatient care, and consultations; 2) infection control; 3) antibiotic stewardship; 4) research; and 5) education and training. We investigated the weekly time-use patterns for these areas of practice. RESULTS: Of the 352 ID specialists, 195 (55.4%; 51.2% [144/281] adult and 71.8% [51/71] pediatric ID specialists) responded in the survey. Moreover, 144 (73.8%) of the total respondents were involved in all practice categories investigated. The most common practice area was outpatient service (93.8%), followed by consultation (91.3%) and inpatient service (87.7%). Specialists worked a median of 61 (interquartile range: 54-71) hours weekly: patient care, 29 (14-37) hours; research 11 (5-19) hours; infection control 4 (2-10) hours; antibiotic stewardship, 3 (1-5) hours; and education/training, 2 (2-6) hours. CONCLUSION: ID specialists in Korea simultaneously undertake multiple tasks and work long hours, highlighting the need for training and employing more ID specialists.