Purpose: This study aimed to assess the real-world clinical outcomes of consolidative durvalumab in patients with unresectable locally advanced non–small cell lung cancer (LA-NSCLC) and to explore the role of radiotherapy in the era of immunotherapy. Materials and Methods: This retrospective study assessed 171 patients with unresectable LA-NSCLC who underwent concurrent chemoradiotherapy (CCRT) with or without consolidative durvalumab at Asan Medical Center between May 2018 and May 2021. Primary outcomes included freedom from locoregional failure (FFLRF), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS). Results: Durvalumab following CCRT demonstrated a prolonged median PFS of 20.9 months (p=0.048) and a 3-year FFLRF rate of 57.3% (p=0.008), compared to 13.7 months and 38.8%, respectively, with CCRT alone. Furthermore, the incidence of in-field recurrence was significantly greater in the CCRT-alone group compared to the durvalumab group (26.8% vs. 12.4%, p=0.027). While median OS was not reached with durvalumab, it was 35.4 months in patients receiving CCRT alone (p=0.010). Patients positive for programmed cell death ligand 1 (PD-L1) expression showed notably better outcomes, including FFLRF, DMFS, PFS, and OS. Adherence to PACIFIC trial eligibility criteria identified 100 patients (58.5%) as ineligible. The use of durvalumab demonstrated better survival regardless of eligibility criteria. Conclusion The use of durvalumab consolidation following CCRT significantly enhanced locoregional control and OS in patients with unresectable LA-NSCLC, especially in those with PD-L1–positive tumors, thereby validating the role of durvalumab in standard care.

Background: This study aimed to generate a Z score calculation model for coronary artery diameter of normal children and adolescents to be adopted as the standard calculation method with consensus in clinical practice. Methods: This study was a retrospective, multicenter study that collected data from multiple institutions across South Korea. Data were analyzed to determine the model that best fit the relationship between the diameter of coronary arteries and independent demographic parameters. Linear, power, logarithmic, exponential, and square root polynomial models were tested for best fit. Results: Data of 2,030 subjects were collected from 16 institutions. Separate calculation models for each sex were developed because the impact of demographic variables on the diameter of coronary arteries differs according to sex. The final model was the polynomial formula with an exponential relationship between the diameter of coronary arteries and body surface area using the DuBois formula. Conclusion A new coronary artery diameter Z score model was developed and is anticipated to be applicable in clinical practice. The new model will help establish a consensus-based Z score model.

Purpose: The detection rate of early-stage lung cancer with ground-glass opacity (GGO) has increased, and stereotactic body radiotherapy (SBRT) has been suggested as an alternative to surgery in inoperable patients. However, reports on treatment results are limited. Therefore, we performed a retrospective study to investigate the clinical outcome after SBRT in patients with early-stage lung cancer with GGO-predominant tumor lesions at a single institution. Materials and Methods: This study included 89 patients with 99 lesions who were treated with SBRT for lung cancer with GGO-predominant lesions that had a consolidation-to-tumor ratio of ≤0.5 at Asan Medical Center between July 2016 and July 2021. A median total dose of 56.0 Gy (range, 48.0–60.0) was delivered using 10.0–15.0 Gy per fraction. Results: The overall follow-up period for the study was median 33.0 months (range, 9.9 to 65.9 months). There was 100% local control with no recurrences in any of the 99 treated lesions. Three patients had regional recurrences outside of the radiation field, and three had distant metastasis. The 1-year, 3-year, and 5-year overall survival rates were 100.0%, 91.6%, and 82.8%, respectively. Univariate analysis revealed that advanced age and a low level of diffusing capacity of the lungs for carbon monoxide were significantly associated with overall survival. There were no patients with grade ≥3 toxicity. Conclusion SBRT is a safe and effective treatment for patients with GGO-predominant lung cancer lesions and is likely to be considered as an alternative to surgery.

Purpose: An optimal once-daily radiotherapy (RT) regimen is under investigation for definitive concurrent chemoradiotherapy (CCRT) in limited disease small cell lung cancer (LD-SCLC). We compared the efficacy and safety of dose escalation with intensity-modulated radiotherapy (IMRT). Materials and Methods: Between January 2016 and March 2021, patients treated with definitive CCRT for LD-SCLC with IMRT were retrospectively reviewed. Patients who received a total dose <50 Gy or those with a history of thoracic RT or surgery were excluded. The patients were divided into two groups (standard and dose-escalated) based on the total biologically effective dose (BED, α/β = 10) of 70 Gy. The chemotherapeutic regimen comprised four cycles of etoposide and cisplatin. Results: One hundred and twenty-two patients were analyzed and the median follow-up was 27.8 months (range, 4.4 to 76.9 months). The median age of the patients was 63 years (range, 35 to 78 years) and the majority had a history of smoking (86.0%). The 1- and 3-year overall survival rates of the escalated dose group were significantly higher than those of the standard group (93.5% and 50.5% vs. 76.7% and 33.3%, respectively; p = 0.008), as were the 1- and 3-year freedom from in-field failure rates (91.4% and 66.5% vs. 73.8% and 46.9%, respectively; p = 0.018). The incidence of grade 2 or higher acute and late pneumonitis was not significantly different between the two groups (p = 0.062, 0.185). Conclusion Dose-escalated once-daily CCRT with IMRT led to improved locoregional control and survival, with no increase in toxicity.

Background: Streptococcus pneumoniae is a serious pathogen causing various infections in humans. We evaluated the serotype distribution and antimicrobial resistance of S. pneumoniae causing invasive pneumococcal disease (IPD) after introduction of pneumococcal conjugate vaccine (PCV)13 in Korea and investigated the epidemiological characteristics of multidrug-resistant (MDR) isolates. Methods: S. pneumoniae isolates causing IPD were collected from 16 hospitals in Korea between 2017 and 2019. Serotyping was performed using modified sequential multiplex PCR and the Quellung reaction. Antimicrobial susceptibility tests were performed using the broth microdilution method. Multilocus sequence typing was performed on MDR isolates for epidemiological investigations. Results: Among the 411 S. pneumoniae isolates analyzed, the most prevalent serotype was 3 (12.2%), followed by 10A (9.5%), 34 (7.3%), 19A (6.8%), 23A (6.3%), 22F (6.1%), 35B (5.8%), 11A (5.1%), and others (40.9%). The coverage rates of PCV7, PCV10, PCV13, and pneumococcal polysaccharide vaccine (PPSV)23 were 7.8%, 7.8%, 28.7%, and 59.4%, respectively. Resistance rates to penicillin, ceftriaxone, erythromycin, and levofloxacin were 13.1%, 9.2%, 80.3%, and 4.1%, respectively. MDR isolates accounted for 23.4% of all isolates. Serotypes 23A, 11A, 19A, and 15B accounted for the highest proportions of total isolates at 18.8%, 16.7%, 14.6%, and 8.3%, respectively. Sequence type (ST)166 (43.8%) and ST320 (12.5%) were common among MDR isolates. Conclusions Non-PCV13 serotypes are increasing among invasive S. pneumoniae strains causing IPD. Differences in antimicrobial resistance were found according to the specific serotype. Continuous monitoring of serotypes and antimicrobial resistance is necessary for the appropriate management of S. pneumoniae infections.

Objective: Elevated levels of cardiac troponin in chronic kidney disease (CKD) patients admitted to the emergency department (ED) is not well understood and is often ignored. This study aimed to investigate the impact of cardiac troponin I (TnI) levels on the clinical outcome of patients visiting the ED with or without CKD. Methods: In this retrospective single-center cohort study, we enrolled patients visiting the ED without a diagnosis of coronary artery disease (CAD). Elevated cardiac TnI was defined as being ≥99th percentile of the normal population (Siemens ADVIA Centaur TnI-Ultra≥0.040 ng/mL). The clinical outcomes of patients with CKD stage≤2 and CKD stage ≥3 were compared. The primary endpoint was the 180-day all-cause death, including cardiovascular and non-cardiovascular deaths. Results: Among a total of 30,472 patients (median age, 61 years; male sex, 54.3%), elevated TnI was found in 4,377 patients (14.4%). There were 3,634 deaths (11.9%) including 584 cardiovascular (1.9%) and 3,050 non-cardiovascular deaths (10.0%). The risk of all-cause death increased in patients with elevated TnI in both CKD stage≤2 (hazard ratio [HR], 2.1; 95% confidence interval [CI], 1.9-2.3) and CKD stage≥3 (HR, 1.5; 95% CI, 1.4-1.7), and so did the risks of cardiovascular and non-cardiovascular death (HR, 1.2-4.7) (P<0.05, all). The association of elevated TnI with death risk was consistent in multivariate analyses and in most clinical subgroup analyses. Conclusion Elevated TnI was associated with higher 180-day mortality irrespective of renal function among patients visiting the ED without documented CAD. CKD patients visiting the ED with elevated TnI may warrant additional evaluation or careful follow-up even without the presence of CAD.

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.

Purpose: This study aimed to investigate the current status of bariatric and metabolic surgery in Daejeon and Chungcheong province and to describe the early experiences after public medical insurance coverage in 2019. Materials and Methods: Between January 2019 and August 2019, 64 cases of bariatric and metabolic surgery were performed in patients with morbid obesity or uncontrolled type 2 diabetes. We prospectively collected and analyzed data regarding the patients’ demographics and comorbidities, surgical results, and early complications. The patient information before and after the insurance coverage was also compared. Results: The number of surgeries in 9 years has been caught up only in the last 8 months after insurance coverage (58 vs. 64 patients). The mean body mass index was 37.7±5.8 kg/m2 (range, 22.7-52.1 kg/m2). The most frequently performed surgery was sleeve gastrectomy (53 cases, 82.8%), followed by Roux-en-Y gastric bypass (9 cases, 14.1%), and adjustable gastric banding (2 cases, 3.1%). Postoperative complications occurred in 6 patients (9.4%), and there was no mortality. The mean operation time (225.3±85.4 vs. 156.1±61.8 min, P＜0.001) and postoperative stay (5.9±4.5 vs. 4.3±2.0 days, P=0.013) after the insurance coverage were significantly shorter than those before the insurance coverage. Conclusion We could assess the patients who had bariatric and metabolic surgery in Daejeon and Chungcheong province after public medical insurance coverage in 2019.

PURPOSE: Croup is known to have epidemics in seasonal and biennial trends, and to be strongly associated with epidemics of parainfluenza virus. However, seasonal and annual epidemics of croup have not been clearly reported in Korea. This study aimed to examine the seasonal/annual patterns and etiologies of childhood croup in Korea during a consecutive 6-year period. METHODS: Pediatric croup data were collected from 23 centers in Korea from 1 January 2010 to 31 December 2015. Electronic medical records, including multiplex reverse transcription polymerase chain reaction (RT-PCR) results, demographics and clinical information were cross-sectionally reviewed and analyzed. RESULTS: Overall, 2,598 childhood croup patients requiring hospitalization were identified during the study period. Among them, a total of 927 who underwent RT-PCR were included in the analysis. Males (61.5%) predominated, and most (63.0%) of them were younger than 2 years of age (median, 19 months; interquartile range, 11–31 months). Peak hospitalization occurred in 2010 and 2012 in even-numbered years, and parainfluenza virus (PIV, 39.7%) was the most common cause of childhood croup requiring hospitalization, followed by respiratory syncytial virus (14.9%), human rhinovirus (12.5%), Mycoplasma pneumonaie (10.6%), and human coronavirus (7.3%). CONCLUSION: It is concluded that croup hospitalization has a biennial pattern in even-numbered years. PIV may be the most common cause of childhood croup; however, croup epidemics could be attributed to other viruses.
Child ; Coronavirus ; Croup ; Demography ; Electronic Health Records ; Hospitalization ; Humans ; Korea ; Male ; Mycoplasma ; Paramyxoviridae Infections ; Polymerase Chain Reaction ; Respiratory Syncytial Viruses ; Retrospective Studies ; Reverse Transcription ; Rhinovirus ; Seasons

BACKGROUND: Salmonella is an important pathogen that causes gastroenteritis and sepsis in humans. Recently, changes in serotype prevalence and an increase in antimicrobial resistance have been reported. This study investigated the distribution of Salmonella serotypes and determined the antimicrobial susceptibility of various strains. METHODS: We collected 113 Salmonella isolates other than Salmonella serotype Typhi from 18 university hospitals in 2015. The serotypes were identified by Salmonella antisera O and H according to the Kauffman White scheme. Antimicrobial susceptibility tests for 12 antibiotics were performed using the disk diffusion method or E-test. RESULTS: We identified 22 serotypes. Serotype group B (44.2%) was the most common, followed by groups C (34.5%) and D (21.2%). Salmonella I 4,[5],12:i:- (23.0%), S. Enteritidis (16.8%), and S. Typhimurium (12.4%) were the most common species. Resistance rates for ampicillin, chloramphenicol, ceftriaxone, and trimethoprim/sulfamethoxazole were 46.9%, 18.5%, 8.8%, and 5.3%, respectively. The intermediate resistance rate to ciprofloxacin was 29.2%. Six isolates were extended-spectrum β-lactamase (ESBL) producers, including 5 bla(CTX-M-15) and 1 bla(CTX-M-55). CONCLUSION: There have been changes in the serotype prevalence and antimicrobial resistance of Salmonella in Korea, with a high prevalence of CTX-M 15-positive strains. Continuous monitoring of Salmonella serotypes and antimicrobial resistance is warranted.
Ampicillin ; Anti-Bacterial Agents ; Ceftriaxone ; Chloramphenicol ; Ciprofloxacin ; Diffusion ; Gastroenteritis ; Hospitals, University ; Humans ; Immune Sera ; Korea ; Methods ; Prevalence ; Salmonella ; Sepsis ; Serogroup ; Serotyping