Purpose: Although pertussis is a vaccine-preventable disease, its incidence increased rapidly in Guro-gu, Seoul, since May 2024. This study aimed to investigate the epidemiological characteristics of pertussis cases and outbreaks during this period. Methods: Data from epidemiologic investigations of 355 laboratory-confirmed pertussis cases reported in 2024 in Guro-gu, Seoul, were analyzed using national surveillance records. Demographics, vaccination status, outbreak-associated educational settings, and symptom-to-test intervals were analyzed using descriptive statistics and non-parametric tests. Results: Between May and December 2024, 355 cases were reported, 85.4% of which occurred among school-aged children and adolescents, representing a marked increase compared with previous years. Outbreaks were identified in two elementary schools, three middle schools, and four private academies, indicating clustered transmission in educational settings, with school-based attack rates ranging from 3.2% to 6.3%. Among 146 outbreak-associated school cases, 95.4% had completed age-appropriate vaccination on time. The symptom-to-test interval showed a right-skewed distribution (median, 6 days; interquartile range, 3–11), with longer delays observed in high school students. Conclusion The sharp increase in pertussis cases among school-aged children underscores the need for strengthened surveillance in educational settings and improved timeliness of testing to reduce transmission. Delays in symptom-to-test intervals and the occurrence of cases despite age-appropriate vaccination suggest possible waning immunity, highlighting the importance of evaluating booster vaccination strategies and targeted age-specific public health interventions.

Background: Although insulin resistance is common, its significance in kidney transplant recipients remains unclear. We explored clinical implications of the triglyceride-glucose (TyG) index as a marker for unfavorable allograft outcomes in kidney transplant recipients. Methods: A total of 6,354 kidney transplant recipients were enrolled in a multicenter prospective cohort study between May 2014 and December 2022. The TyG index was assessed between 6 and 12 months after transplantation. We evaluated the association between the TyG index and the risk of adverse kidney outcomes. Results: The cumulative rates of ≥50% decline in estimated glomerular filtration rate (eGFR), death-censored graft survival, and major adverse kidney events differed across TyG index quartiles, with the highest rate observed in quartile 4 (p < 0.001). TyG index quartile 4 was associated with the highest risk of death-censored graft loss after multivariable adjustment (adjusted hazard ratio, 2.13; 95% confidence interval [CI], 1.28–3.55). The risk of ≥30% decline in eGFR was 1.46 times higher (95% CI, 1.17–1.82) in quartile 4 compared with quartile 1, and the risk of ≥50% decline was 1.78 times higher (95% CI, 1.30–2.44). Quartile 4 also showed a significantly steeper decline in renal function, with an adjusted mean difference in eGFR slope of –4.72 mL/min/1.73 m2 (95% CI, –7.39 to –2.04). Conclusion Kidney transplant recipients with high TyG index were at increased risk of eGFR decline and graft loss, and also exhibited a more rapid deterioration in renal function. The TyG index is a useful marker for identifying individuals at high risk for adverse graft outcomes.

OBJECTIVES: Tobacco use ranks among the leading preventable causes of death worldwide. This study was conducted to calculate the mortality rate attributable to smoking in Korea for 2019 and to highlight the importance of tracking and monitoring smoking-related deaths for public health purposes. METHODS: Population attributable risk (PAR) was used to estimate the number of deaths related to smoking in 2019. PAR percentages were applied to the estimated mortality figures for various diseases, with PAR determined based on relative risk (RR). Levin’s formula was used to calculate PAR, and RR was adjusted for age and alcohol consumption using Cox proportional hazards regression model to derive disease-specific regression coefficients. The analysis incorporated previously determined smoking rates from 1985, and use rates of novel tobacco products were not considered. RESULTS: The findings revealed a total of 67,982 smoking-attributable deaths in Korea in 2019, 56,993 of which occurred in men and 11,049 in women. The PAR of smoking for various causes of death in adult men was highest for lung cancer at 74.9%, followed by pneumonia (29.4%), ischemic heart disease (42.3%), and stroke (30.2%). For women, the PAR for smoking-related death was highest for lung cancer (19.9%), followed by stroke (7.6%), pneumonia (5.7%), and ischemic heart disease (9.1%). CONCLUSIONS In countries experiencing rapid fluctuations in smoking rates, including Korea, regular studies on smoking-related mortality is imperative. Furthermore, it is necessary to investigate smoking-related deaths, including the prevalence of novel tobacco product use, to accurately gauge the risks associated with emerging tobacco products.

Background: The pathophysiological mechanisms underlying the post-acute sequelae of severe acute respiratory syndrome coronavirus 2 infection (PASC) are not well understood.Our study aimed to investigate various aspects of theses mechanisms, including viral persistence, immunological responses, and laboratory parameters in patients with and without PASC. Methods: We prospectively enrolled adults aged ≥ 18 years diagnosed with coronavirus disease 2019 (COVID-19) between August 2022 and July 2023. Blood samples were collected at three time-points: within one month of diagnosis (acute phase) and at 1 month, and 3 months post-diagnosis. Following a recent well-designed definition of PASC, PASC patients were defined as those with a questionnaire-based PASC score ≥ 12 persisting for at least 4 weeks after the initial COVID-19 diagnosis. Results: Of 57 eligible COVID-19 patients, 29 (51%) had PASC, and 28 (49%) did not. The PASC group had significantly higher nucleocapsid protein (NP) antigenemia 3 months after COVID-19 diagnosis (P = 0.022). Furthermore, several cytokines, including IL-2, IL-17A, VEGF, RANTES, sCD40L, IP-10, I-TAC, and granzyme A, were markedly elevated in the PASC group 1 and/or 3 month(s) after COVID-19 diagnosis. In contrast, the median values of several serological markers, including thyroid markers, autoimmune indicators, and stress-related hormones, were within the normal range. Conclusion Levels of NP antigen and of various cytokines involved in immune responses become significantly elevated over time after COVID-19 diagnosis in PASC patients compared to non-PASC patients. This suggests that PASC is associated with prolonged immune dysregulation resulting from heightened antigenic stimulation.

Objectives: Estimating the number of deaths caused by smoking is crucial for developing and evaluating tobacco control and smoking cessation policies. This study aimed to determine smoking-attributable mortality (SAM) in Korea in 2020. Methods: Four large-scale cohorts from Korea were analyzed. A Cox proportional-hazards model was used to determine the hazard ratios (HRs) of smoking-related death. By conducting a meta-analysis of these HRs, the pooled HRs of smoking-related death for 41 diseases were estimated. Population-attributable fractions (PAFs) were calculated based on the smoking prevalence for 1995 in conjunction with the pooled HRs. Subsequently, SAM was derived using the PAF and the number of deaths recorded for each disease in 2020. Results: The pooled HR for all-cause mortality attributable to smoking was 1.73 for current men smokers (95% confidence interval [CI], 1.53 to 1.95) and 1.63 for current women smokers (95% CI, 1.37 to 1.94). Smoking accounted for 33.2% of all-cause deaths in men and 4.6% in women. Additionally, it was a factor in 71.8% of men lung cancer deaths and 11.9% of women lung cancer deaths. In 2020, smoking was responsible for 53 930 men deaths and 6283 women deaths, totaling 60 213 deaths. Conclusions Cigarette smoking was responsible for a significant number of deaths in Korea in 2020. Monitoring the impact and societal burden of smoking is essential for effective tobacco control and harm prevention policies.

PURPOSE: The purpose of this descriptive, cross-sectional study was to identify the factors affecting health-related quality of life by examining the relationships among posttraumatic stress, health-related work limitations, and family support in firefighters. METHODS: The data were collected from 390 firefighters working in four fire stations located in the G district using self-report questionnaires. The collected data were analyzed using descriptive statistics, t-test, one-way ANOVA along with the Scheffé test, and multiple regression. RESULTS: As per the results of multiple regression analysis, the factors affecting health-related quality of life in firefighters were posttraumatic stress, health-related work limitations, and family support. This model explained 31% of the variance in health-related quality of life (F=30.03, p<.001). CONCLUSION: Considering the findings of this study, there is a need to reduce posttraumatic stress and health-related work limitations and develop family support toward firefighters.
Cross-Sectional Studies ; Firefighters* ; Fires ; Humans ; Quality of Life*

BACKGROUND/AIMS: Several studies suggest that pyogenic liver abscess (PLA) is associated with colon neoplasm. A colonoscopic exam for cryptogenic PLA might detect a hidden colon neoplasm, through which intestinal flora can be transmitted into the liver. However, there are no prospectively enrolled cross-sectional data for colonic neoplasm in cryptogenic PLA. METHODS: Patients with PLA were prospectively enrolled from two university hospitals. Among them, all the patients with cryptogenic PLA were recommended for colonoscopic exam to check for colonic neoplasm. RESULTS: One hundred eighty-three patients with PLA were enrolled in the study for 22 months. One hundred and one (55.2%) patients did not have a definite cause of liver abscess at initial evaluation. The median diameter of the largest lesion was 5.7 cm (1.0-14.0 cm), and 74.3% of the patients were treated by percutaneous abscess drainage. Ninety-one percent of the patients who had an identified pathogen yielded Klebsiella. Sixty-two patients underwent colonoscopic exams, and no one had a colonic cancer, one had an adenomatous polyp with high grade dysplasia (1.6%), and 27 had adenomatous polyps with low grade dysplasia (43.5%; 41.0% in male and 43.5% in female). Of fifty patients who underwent an esophagogastroduodeno-scopic exam, nine had gastric ulcers, one had an esophageal ulcer, and one had hemorrhagic gastritis. CONCLUSIONS: The prevalence of colonic neoplasm among the patients with cryptogenic PLA was not as high as that in previous studies. Further well-designed, large-scale studies are required to assess the association of the colon neoplasm and cryptogenic PLA.
Abscess ; Adenomatous Polyps ; Colon* ; Colonic Neoplasms* ; Cross-Sectional Studies* ; Drainage ; Gastritis ; Gastrointestinal Microbiome ; Hospitals, University ; Humans ; Klebsiella ; Liver ; Liver Abscess ; Liver Abscess, Pyogenic* ; Male ; Prevalence* ; Prospective Studies* ; Stomach Ulcer ; Ulcer

PURPOSE: Treatment of patients with para-aortic lymph node metastasis from colorectal cancer is controversial. The goal of this study was to investigate the technical feasibility of laparoscopic intrarenal para-aortic lymph node dissection in patients with colorectal cancer and clinically suspected para-aortic lymph node dissection. METHODS: The inclusion criteria for the laparoscopic approach were patients with infrarenal para-aortic lymph node metastasis from colorectal cancer. Patients who had any other distant metastatic lesion or metachronous para-aortic lymph node metastasis were excluded from this study. Perioperative outcomes and survival outcomes were analyzed. RESULTS: Between November 2004 and October 2013, 40 patients underwent laparoscopic para-aortic lymph node dissection. The mean operating time was 192.3 +/- 68.8 minutes (range, 100-400 minutes) and the mean estimated blood loss was 65.6 +/- 52.6 mL (range, 20-210 mL). No patient required open conversion. The postoperative complication rate was 15.0%. Sixteen patients (40.0%) had pathologically positive lymph nodes. In patients with metastatic para-aortic lymph nodes, the 3-year overall survival rate and disease-free survival rate were 65.7% and 40.2%, respectively. CONCLUSION: The results of our study suggest that a laparoscopic approach for patients with colorectal cancer with metastatic para-aortic lymph nodes can be a reasonable option for selected patients.
Colorectal Neoplasms* ; Disease-Free Survival ; Humans ; Laparoscopy ; Lymph Node Excision* ; Lymph Nodes* ; Neoplasm Metastasis ; Postoperative Complications ; Survival Rate

BACKGROUND: Successful pregnancy outcomes in patients with advanced chronic kidney disease (CKD) are increasingly common in Western countries. However, in Korea, the available literature addressing this clinical issue is scarce. METHODS: We reviewed 5 successful parturitions [1 patient with Stage 5 CKD and 4 with maintenance hemodialysis (HD)] at Seoul St. Mary's Hospital over 3 years and investigated changes in dialysis prescription, anemia management, and the incidence of maternal and neonatal complications. RESULTS: There were no maternal or neonatal deaths in this cohort. The mean age at the time of conception and delivery was 35.8 ± 3.7 and 36.2 ± 3.5 years, respectively. Dialysis patients received more frequent and intensified HD during pregnancy, 20.0 ± 5.7 h/wk of HD over 5 visits with the ultrafiltration dose maintained between 1 and 2 kg per session. All patients received erythropoietin-stimulating agents and iron replacement therapy during pregnancy. The mean hematocrit was 33.1 ± 1.9% before pregnancy and was well maintained during gestation (33.9 ± 3.8% at the first trimester, 29.2 ± 4.2% at the second trimester, and 33.6 ± 8.7% at delivery). The mean gestation period was 32.7 ± 4.7 weeks, with 60% of patients experiencing premature delivery. The primary maternal complication was pre-eclampsia; 3 women developed pre-eclampsia and underwent emergency cesarean sections. Most neonatal complications were related to preterm birth. CONCLUSION: Dialysis-related care and general clinical management improved the clinical outcome of pregnancy for patients with advanced CKD.
Anemia ; Cesarean Section ; Cohort Studies ; Dialysis ; Emergencies ; Female ; Fertilization ; Hematocrit ; Humans ; Incidence ; Iron ; Korea ; Parturition ; Perinatal Death ; Pre-Eclampsia ; Pregnancy ; Pregnancy Outcome ; Pregnancy Trimester, First ; Pregnancy Trimester, Second ; Pregnant Women* ; Premature Birth ; Prescriptions ; Renal Dialysis ; Renal Insufficiency, Chronic* ; Seoul ; Ultrafiltration