Background: We aimed to analyze the effects of an antimicrobial stewardship program (ASP) on the proportion of antimicrobial-resistant pathogens in bacteremia, antimicrobial use, and mortality in pediatric patients. Methods: A retrospective single-center study was performed on pediatric inpatients under 19 years old who received systemic antimicrobial treatment from 2001 to 2019. A pediatric infectious disease attending physician started ASP in January 2008. The study period was divided into the pre-intervention (2001–2008) and the post-intervention (2009–2019) periods. The amount of antimicrobial use was defined as days of therapy per 1,000 patientdays, and the differences were compared using delta slope (= changes in slopes) between the two study periods by an interrupted time-series analysis. The proportion of resistant pathogens and the 30-day overall mortality rate were analyzed by the χ2 . Results: The proportion of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae bacteremia increased from 17% (39 of 235) in the pre-intervention period to 35% (189 of 533) in the post-intervention period (P < 0.001). The total amount of antimicrobial use significantly decreased after the introduction of ASP (delta slope value = −16.5; 95% confidence interval [CI], −30.6 to −2.3; P = 0.049). The 30-day overall mortality rate in patients with bacteremia did not increase, being 10% (55 of 564) in the pre-intervention and 10% (94 of 941) in the post-intervention period (P = 0.881). Conclusion The introduction of ASP for pediatric patients reduced the delta slope of the total antimicrobial use without increasing the mortality rate despite an increased incidence of ESBL-producing gram-negative bacteremia.

Background: The aim of this study was to capture multifaceted clinical characteristics of congenital cytomegalovirus (CMV) infection from diagnosis to treatment using a multidisciplinary approach including obstetrics, pediatrics, pathology, and otorhinolaryngology-head and neck surgery. Methods: This is a retrospective study including 30 consecutive cases of congenital CMV infection that were diagnosed at a single tertiary hospital located in Seoul, Korea from January 2009 to December 2020. Congenital CMV infection was defined as a positive result by polymerase chain reaction from urine, saliva or cerebrospinal fluid or positive CMV IgM from neonatal blood sampled within 3 weeks after birth. All cases were analyzed with respect to whole clinical characteristics from diagnosis to treatment of congenital CMV by a multidisciplinary approach including prenatal sonographic findings, maternal immune status regarding CMV infection, detailed placental pathology, neonatal clinical manifestation, auditory brainstem response test, and antiviral treatment (ganciclovir or valganciclovir). Long-term outcomes including developmental delay and hearing loss were also investigated. Results: The total number of births during the study period in our institution was 19,385, with the prevalence of congenital infection estimated to be 0.15%. Among 30 cases of congenital CMV, the median gestational age at delivery was 32.2 weeks [range, 22.6–40.0] and 66.7% of these infants were delivered preterm at less than 37 weeks. Suspected fetal growth restriction was the most common prenatal ultrasound finding (50%) followed by ventriculomegaly (17.9%) and abnormal placenta (17.9%), defined as thick placenta with calcification. No abnormal findings on ultrasound examination were observed in one-third of births. Maternal CMV serology tests were conducted in only 8 cases, and one case each of positive and equivocal IgM were found. The most common placental pathologic findings were chronic villitis (66.7%) and calcification (63.0%), whereas viral inclusions were identified in only 22.2%. The most common neonatal manifestations were jaundice (58.6%) followed by elevation of aspartate aminotransferase (55.2%) and thrombocytopenia (51.7%). After excluding cases for which long-term outcomes were unavailable due to death (n = 4) or subsequent follow up loss (n = 3), developmental delay was confirmed in 43.5% of infants (10/23), and hearing loss was confirmed in 42.9% (9/21) during the follow-up period. In our cohort, 56.7% (17/30) of neonates were treated for congenital CMV with ganciclovir or valganciclovir. Conclusion Our data show that prenatal findings including maternal serologic tests and ultrasound have limited ability to detect congenital CMV in Korea. Given that CMV is associated with high rates of developmental delay and hearing loss in infants, there is an urgent need to develop specific strategies for the definite diagnosis of congenital CMV infection during the perinatal period by a multidisciplinary approach to decrease the risks of neurologic impairment and hearing loss through early antiviral treatment.

Purpose: We aimed to assess the humoral response to and reactogenicity of coronavirus disease 2019 (COVID-19) vaccination according to the vaccine type and to analyze factors associated with immunogenicity in actively treated solid cancer patients (CPs). Materials and Methods: Prospective cohorts of CPs, undergoing anticancer treatment, and healthcare workers (HCWs) were established. The participants had no history of previous COVID-19 and received either mRNA-based or adenovirus vector–based (AdV) vaccines as the primary series. Blood samples were collected before the first vaccination and after 2 weeks for each dose vaccination. Spike-specific binding antibodies (bAbs) in all participants and neutralizing antibodies (nAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) wild-type, Delta, and Omicron variants in CPs were analyzed and presented as the geometric mean titer. Results: Age-matched 20 HCWs and 118 CPs were included in the analysis. The bAb seroconversion rate and antibody concentrations after the first vaccination were significantly lower in CPs than in HCWs. After the third vaccination, antibody levels in CPs with a primary series of AdV were comparable to those in HCWs, but nAb titers against the Omicron variant did not quantitatively increase in CPs with AdV vaccine as the primary series. The incidence and severity of adverse reactions post-vaccination were similar between CPs and HCWs. Conclusion CPs displayed delayed humoral immune response after SARS-CoV-2 vaccination. The booster dose elicited comparable bAb concentrations between CPs and HCWs, regardless of the primary vaccine type. Neutralization against the Omicron variant was not robustly elicited following the booster dose in some CPs, implying the need for additional interventions to protect them from COVID-19.

Background: The coronavirus disease-2019 (COVID-19) pandemic has contributed to the change in the epidemiology of many infectious diseases. This study aimed to establish the pre-pandemic epidemiology of pediatric invasive bacterial infection (IBI). Methods: A retrospective multicenter-based surveillance for pediatric IBIs has been maintained from 1996 to 2020 in Korea. IBIs caused by eight bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Listeria monocytogenes, and Salmonella species) in immunocompetent children > 3 months of age were collected at 29 centers. The annual trend in the proportion of IBIs by each pathogen was analyzed. Results: A total of 2,195 episodes were identified during the 25-year period between 1996 and 2020. S. pneumoniae (42.4%), S. aureus (22.1%), and Salmonella species (21.0%) were common in children 3 to 59 months of age. In children ≥ 5 years of age, S. aureus (58.1%), followed by Salmonella species (14.8%) and S. pneumoniae (12.2%) were common. Excluding the year 2020, there was a trend toward a decrease in the relative proportions of S. pneumoniae (rs = −0.430, P = 0.036), H. influenzae (rs = −0.922, P < 0.001), while trend toward an increase in the relative proportion of S. aureus (rs = 0.850, P < 0.001), S. agalactiae (rs = 0.615, P = 0.001), and S. pyogenes (rs = 0.554, P = 0.005). Conclusion In the proportion of IBIs over a 24-year period between 1996 and 2019, we observed a decreasing trend for S. pneumoniae and H. influenzae and an increasing trend for S. aureus, S. agalactiae, and S. pyogenes in children > 3 months of age. These findings can be used as the baseline data to navigate the trend in the epidemiology of pediatric IBI in the post COVID-19 era.

Purpose: Atrial fibrillation (AF) patients with low to intermediate risk, defined as non-gender CHA2DS2-VASc score of 0–1, are still at risk of stroke. This study verified the usefulness of ABCD score [age (≥60 years), B-type natriuretic peptide (BNP) or N-terminal pro-BNP (≥300 pg/mL), creatinine clearance (<50 mL/min/1.73 m2 ), and dimension of the left atrium (≥45 mm)] for stroke risk stratification in non-gender CHA2DS2-VASc score 0–1. Materials and Methods: This multi-center cohort study retrospectively analyzed AF patients with non-gender CHA2DS2-VASc score 0–1. The primary endpoint was the incidence of stroke with or without antithrombotic therapy (ATT). An ABCD score was validated. Results: Overall, 2694 patients [56.3±9.5 years; female, 726 (26.9%)] were followed-up for 4.0±2.8 years. The overall stroke rate was 0.84/100 person-years (P-Y), stratified as follows: 0.46/100 P-Y for an ABCD score of 0; 1.02/100 P-Y for an ABCD score ≥1. The ABCD score was superior to non-gender CHA2DS2-VASc score in the stroke risk stratification (C-index=0.618, p=0.015; net reclassification improvement=0.576, p=0.040; integrated differential improvement=0.033, p=0.066). ATT was prescribed in 2353 patients (86.5%), and the stroke rate was significantly lower in patients receiving non-vitamin K antagonist oral anticoagulant (NOAC) therapy and an ABCD score ≥1 than in those without ATT (0.44/100 P–Y vs. 1.55/100 P-Y; hazard ratio=0.26, 95% confidence interval 0.11–0.63, p=0.003). Conclusion The biomarker-based ABCD score demonstrated improved stroke risk stratification in AF patients with non-gender CHA2DS2-VASc score 0–1. Furthermore, NOAC with an ABCD score ≥1 was associated with significantly lower stroke rate in AF patients with non-gender CHA2DS2-VASc score 0–1.

Objective: To investigate whether there is a link between cognitive function and motor reserve (i.e., individual capacity to cope with nigrostriatal dopamine depletion) in patients with newly diagnosed Parkinson’s disease (PD). Methods: A total of 163 patients with drug-naïve PD who underwent 18F-FP-CIT PET, brain MRI, and a detailed neuropsychological test were enrolled. We estimated individual motor reserve based on initial motor deficits and striatal dopamine depletion using a residual model. We performed correlation analyses between motor reserve estimates and cognitive composite scores. Diffusion connectometry analysis was performed to map the white matter fiber tracts, of which fractional anisotropy (FA) values were well correlated with motor reserve estimates. Additionally, Cox regression analysis was used to assess the effect of initial motor reserve on the risk of dementia conversion. Results: The motor reserve estimate was positively correlated with the composite score of the verbal memory function domain (γ = 0.246) and with the years of education (γ = 0.251). Connectometry analysis showed that FA values in the left fornix were positively correlated with the motor reserve estimate, while no fiber tracts were negatively correlated with the motor reserve estimate. Cox regression analysis demonstrated that higher motor reserve estimates tended to be associated with a lower risk of dementia conversion (hazard ratio, 0.781; 95% confidence interval, 0.576–1.058). Conclusion The present study demonstrated that the motor reserve estimate was well correlated with verbal memory function and with white matter integrity in the left fornix, suggesting a possible link between cognition and motor reserve in patients with PD.

Neutralizing antibodies targeted at the receptor-binding domain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein have been developed and now under evaluation in clinical trials. The US Food and Drug Administration currently issued emergency use authorizations for neutralizing monoclonal antibodies in non-hospitalized patients with mild to moderate coronavirus disease 2019 (COVID-19) who are at high risk for progressing to severe disease and/or hospitalization. In terms of this situation, there is an urgent need to investigate the clinical aspects and to develop strategies to deploy them effectively in clinical practice. Here we provide guidance for the use of anti-SARS-CoV-2 monoclonal antibodies for the treatment of COVID-19 based on the latest evidence.

Despite the global effort to mitigate the spread, coronavirus disease 2019 (COVID-19) has become a pandemic that took more than 2 million lives. There are numerous ongoing clinical studies aiming to find treatment options and many are being published daily. Some effective treatment options, albeit of variable efficacy, have been discovered. Therefore, it is necessary to develop an evidence-based methodology, to continuously check for new evidence, and to update recommendations accordingly. Here we provide guidelines on pharmaceutical treatment for COVID-19 based on the latest evidence.

Neutralizing antibodies targeted at the receptor-binding domain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein have been developed and now under evaluation in clinical trials. The US Food and Drug Administration currently issued emergency use authorizations for neutralizing monoclonal antibodies in non-hospitalized patients with mild to moderate coronavirus disease 2019 (COVID-19) who are at high risk for progressing to severe disease and/or hospitalization. In terms of this situation, there is an urgent need to investigate the clinical aspects and to develop strategies to deploy them effectively in clinical practice. Here we provide guidance for the use of anti-SARS-CoV-2 monoclonal antibodies for the treatment of COVID-19 based on the latest evidence.

Despite the global effort to mitigate the spread, coronavirus disease 2019 (COVID-19) has become a pandemic that took more than 2 million lives. There are numerous ongoing clinical studies aiming to find treatment options and many are being published daily. Some effective treatment options, albeit of variable efficacy, have been discovered. Therefore, it is necessary to develop an evidence-based methodology, to continuously check for new evidence, and to update recommendations accordingly. Here we provide guidelines on pharmaceutical treatment for COVID-19 based on the latest evidence.