Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally, leading to the coronavirus disease 2019 (COVID-19) pandemic. Because a significant proportion of the COVID-19 confirmed cases were concentrated in the capital metropolitan area of South Korea, and a large proportion of the population in the area had been adequately vaccinated against COVID-19, we conducted a seroprevalence surveillance study focusing on the residents of the capital metropolitan area in South Korea. Methods: We used a quota-sampling method to obtain blood samples from 1,000 individuals per round, equally stratified across seven age categories and sexes and regions, from five medical institutions located within the capital metropolitan area of South Korea. During five consecutive months (rounds) between January 2022 and May 2022, a total of 5,000 samples were analyzed for anti-spike (S) and anti-nucleocapsid (N) antibodies. Results: High anti-S seropositivity was observed in all age groups, which corresponded to the vaccine coverage during the study period. Both the cumulative incidence based on polymerase chain reaction (PCR) and the estimated seroprevalence based on anti-N seropositivity increased in the fourth and fifth rounds, which corresponded to April 2022 and May 2022. Seroprevalence coincided with the cumulative incidence during the first three rounds, but exceeded from the fourth survey onwards when infection with omicron variants was increased rapidly in Korea. Conclusion Seroprevalence confirmed the number of infection cases outside of PCR testing-based surveillance. Seroepidemiological surveillance can help us understand vaccine responses and detect hidden infections, thereby providing appropriate public health guidance for achieving population-level immunity.

BACKGROUND: Extraction of cell-free DNA (cfDNA) is a key step for determining the quality of cfDNA-related molecular diagnostics. We evaluated the effect of sample containers and sample storage conditions on cfDNA extraction. METHODS: The cfDNA extraction using the MagMAX Cell-Free DNA Isolation Kit from five healthy controls and five lung cancer patients was evaluated according to the type of sample container and storage conditions: K2-EDTA container, <1, 6, 24, and 48 hr storage at 4℃ after immediate plasma separation; and Cell-Free DNA BCT container, <1, 3, 7, and 14 days stored at room temperature. Mutation analysis of EGFR exons 18–21 was performed. To assess the effect of a delay in centrifugation, EDTA whole blood samples from five healthy individuals were stored at 4℃ for 6, 12, and 24 hr before plasma separation. RESULTS: There was no significant difference in the amount and nucleic acid size of cfDNA in both controls and patients with cancer when EDTA plasma was stored at 4℃ up to 48 hr. The amount and size of cfDNA in the BCT container were not different up to 7 days; however, the 14-day sample showed an increase in cfDNA concentration due to genomic DNA contamination. EGFR mutations were detected on EDTA containers up to 48 hr and with BCT containers up to 14 days. When EDTA whole blood was stored at 4℃ and plasma separation was delayed, the cfDNA concentration increased from 24 hr. CONCLUSIONS: The cfDNA extraction was affected by the sample containers and storage conditions.
Biopsy ; Centrifugation ; DNA Contamination ; DNA ; Edetic Acid ; Exons ; Humans ; Lung Neoplasms ; Pathology, Molecular ; Plasma

OBJECTIVE: We evaluated efficacy of combining proximal balloon guiding catheter (antegrade flow arrest) and distal access catheter (aspiration at the site of occlusion) in thrombectomy for anterior circulation ischemic stroke.METHODS: We retrospectively analyzed 116 patients who underwent mechanical thrombectomy with stent retriever. The patients were divided by the techniques adopted, the combined technique (proximal balloon guiding catheter and large bore distal access catheter) group (n=57, 49.1%) and the conventional (guiding catheter with stent retriever) technique group (n=59, 50.9%). We evaluated baseline characteristics (epidemiologic data, clinical and imaging characteristics) and procedure details (the number of retrieval attempts, procedure time), as well as angiographic (thrombolysis in cerebral infarction (TICI) score, distal thrombus migration) and clinical outcome (National Institutes of Health Stroke Scale at discharge, modified Rankin Scale [mRS] at 3 months) of them.RESULTS: The number of retrieval attempts was lower (p=0.002) and the first-pass successful reperfusion rate was higher (56.1% vs. 28.8%; p=0.003) in the combined technique group. And the rate of final result of TICI score 3 was higher (68.4% vs. 28.8%; p<0.01) and distal thrombus migration rate was also lower (15.8% vs. 40.7%; p=0.021) in the combined technique group. Early strong neurologic improvement (improvement of National Institutes of Health Stroke Scale ≥11 or National Institutes of Health Stroke Scale ≤1 at discharge) rate (57.9% vs. 36.2%; p=0.02) and favorable clinical outcome (mRS at 3 months ≤2) rate (59.6% vs. 33.9%; p=0.005) were also better in the combined technique group.CONCLUSION: The combined technique needs lesser attempts, decreases distal migration, increases TICI 3 reperfusion and achieves better clinical outcomes.
Academies and Institutes ; Brain Ischemia ; Catheters ; Cerebral Infarction ; Humans ; National Institutes of Health (U.S.) ; Reperfusion ; Retrospective Studies ; Stents ; Stroke ; Thrombectomy ; Thrombosis

BACKGROUND: The aim of this study was to describe the structure, organization, management, and staffing of pediatric critical care (PCC) in Korea. METHODS: We directed a questionnaire survey for all Upper Grade General Hospitals (n = 43) in Korea in 2015. The first questionnaire was mainly about structure, organization, and staffing and responses were obtained from 32 hospitals. The second questionnaire was mainly about patients and management. Responses to second questionnaire were obtained from 18 hospitals. RESULTS: Twelve from 32 Upper Grade General Hospitals had pediatric intensive care units (PICUs) and 11 of them had the PICU which was exclusive for children. Total number of PICU beds in Korea was 113. The ratio of the number of PICU beds to the number of children was 1:77,460 in Korea and this ratio is lower than that of other developed countries. The mean number of beds in the PICUs was 9.4 ± 9.3 (range, 2–30). There were 16 medical doctors who were assigned for PCC and only 5 of them were full time pediatric intensivists. In the 18 Upper Grade General Hospitals that responded to the second questionnaire survey, there were 97 patients in the PICUs with an average number of 5.7 ± 7.2 (range, 0–22) on the survey day. The mean age of the patients was 3.4 ± 5.6 years. The mean length of hospital stay was 82 ± 271 days. The mean Pediatric Risk of Mortality score III was 9.4 ± 7.8 at the time of admission to the PICUs. CONCLUSION: There is a considerable shortage of PICU beds compared to those in developed countries. In addition, the proportion of PICUs with PCC specialists is much lower than those in the US and European countries.
Child ; Critical Care* ; Developed Countries ; Hospitals, General ; Humans ; Intensive Care Units, Pediatric ; Korea* ; Length of Stay ; Mortality ; Specialization

PURPOSE: We propose an equation that predicts graft function after kidney transplantation by using donated kidney volume and recipient body surface area (BSA). MATERIALS AND METHODS: Included were 261 cases of living kidney transplantation between 2007 and 2009. Preoperative computed tomography scans were performed and the donated kidney volume was measured by use of a three-dimensional reconstruction program (Ripidia). The estimated glomerular filtration rate (eGFR) was calculated by using the modification of diet in renal disease formula. Donated kidney volume, preoperative renal function, and demographic factors of both donors and recipients were evaluated as predictors. RESULTS: The mean ages of the donors and recipients were 40.8 and 41.6 years, respectively. The mean donated kidney volume and donated kidney volume/recipient BSA ratio were 153.4 mL and 96.9 mL/m2, respectively. Mean preoperative and postoperative 12-month eGFR of recipients were 7.1 and 59.7 mL/min, respectively, and the mean preoperative eGFR of donors was 92.2 mL/min. Donated kidney volume/recipient BSA ratio, donor age, and recipient gender were the significant predictors of eGFR level (p<0.001) and eGFR<45 mL/min at postoperative 12 months (p=0.005, p<0.001, and p=0.006). From the multiple linear regression equation and predicted probability from logistic regression, we could calculate the equation for the ratio of living donor kidney volume to recipient BSA on graft function. CONCLUSIONS: Graft kidney volume/recipient BSA ratio, donor age, and recipient gender were predictors of graft function 12 months after kidney transplantation. Although we are concerned only with the preoperative, this equation model could help physicians to counsel patients concerning their postoperative prognosis and to avoid insufficient volume donations.
Body Surface Area* ; Delayed Graft Function ; Demography ; Diet ; Glomerular Filtration Rate ; Humans ; Kidney Transplantation ; Kidney* ; Linear Models ; Living Donors* ; Logistic Models ; Organ Size ; Prognosis ; Tissue Donors ; Transplantation ; Transplants*

OBJECTIVE: We aimed to evaluate the psychometric properties of the IADL measure included in the Dementia Care Assessment Packet (DCAP-IADL) in dementia patients. METHODS: The study involved 112 dementia patients and 546 controls. The DCAP-IADL was scored in two ways: observed score (OS) and predicted score (PS). The reliability of the DCAP-IADL was evaluated by testing its internal consistency, inter-rater reliability and test-retest reliability. Discriminant validity was evaluated by comparing the mean OS and PS between dementia patients and controls by ANCOVA. Pearson or Spearman correlation analysis was performed with other instruments to assess concurrent validity. Receiver operating characteristics curve analysis was performed to examine diagnostic accuracy. RESULTS: Chronbach's alpha coefficients of the DCAP-IADL were above 0.7. The values in dementia patients were much higher (OS=0.917, PS=0.927), indicating excellent degrees of internal consistency. Inter-rater reliabilities and test-retest reliabilities were statistically significant (p<0.05). PS exhibited higher reliabilities than OS. The mean OS and PS of dementia patients were significantly higher than those of the non-demented group after controlling for age, sex and education level. The DCAP-IADL was significantly correlated with other IADL instruments and MMSE-KC (p<0.001). Areas under the curves of the DCAP-IADL were above 0.9. CONCLUSION: The DCAP-IADL is a reliable and valid instrument for evaluating instrumental ability of daily living for the elderly, and may also be useful for screening dementia. Moreover, administering PS may enable the DCAP-IADL to overcome the differences in gender, culture and life style that hinders accurate evaluation of the elderly in previous IADL instruments.
Activities of Daily Living* ; Aged ; Dementia* ; Humans ; Life Style ; Mass Screening ; Psychometrics ; ROC Curve

BACKGROUND: The criteria by Camitta for diagnosis in severe aplastic anemia (SAA) has been used since 1976. However, there has been no attempt to verify the Camitta's criteria, that the survival in patients with SAA may differ by absolute neutrophil count (ANC), platelet count (PLT), and corrected reticulocyte count (CRC), which are components of the Camitta's criteria. METHODS: 117 SAA patients diagnosed by the Camitta's criteria were analyzed, retrospectively. Univariate and multivariate analyses were used to evaluate the factors affecting overall survival (OS). RESULTS: Response by immunosuppressive therapy (IST) or stem cell transplantation (SCT) significantly affected OS (P=0.001). Therefore, we excluded treatment responders for analysis. Finally, 92 SAA patients including treatment non-responders by IST or SCT and conservative care group were analyzed by using univariate and multivariate analyses. The median age of analyzed patients was 54.5 years. Male to female ratio was 1:1. The median follow-up duration was 74.23 months (range, 54.71-93.74 months). The median ANC, PLT, and CRC were 394/microL, 12,000/microL, and 0.39%, respectively. In multivariate analyses, ANC <500/microL or > or =500/microL (P=0.015, HR 2.694, 95% CI: 1.20-6.01) and age (P=0.015, HR 1.022, 95% CI: 1.00-1.04) were the significant factors for OS. CONCLUSION: ANC could be an essential, not an optional criterion for diagnosing SAA. This study suggests the possibility that the Camitta's criteria be modified. Studies in large cohorts are needed to transform the Camitta's criteria.
Anemia, Aplastic ; Cohort Studies ; Female ; Follow-Up Studies ; Humans ; Male ; Multivariate Analysis ; Neutrophils ; Platelet Count ; Reticulocyte Count ; Retrospective Studies ; Stem Cell Transplantation

PURPOSE: Peritoneal carcinomatosis (PC) of colorectal cancer (CRC) is common and is the second most common cause of death. Clinical studies regarding chemotherapy for CRC with PC have been classically rather limited in scope. We evaluated the efficacy of modified oxaliplatin, leucovorin, and fluorouracil (m-FOLFOX4) regimen for PC of CRC origin. MATERIALS AND METHODS: CRC patients with PC were treated with cycles of oxaliplatin at 85 mg/m2 on day 1, leucovorin 20 mg/m2 followed by 5-fluorouracil (5-FU) via a 400 mg/m2 bolus and a 22 hours continuous infusion of 600 mg/m2 5-FU on days 1-2 at 2-week intervals. RESULTS: Forty patients participated in this study. Median age was 55 years. Thirty-two patients (80.0%) received previous operation, and 60.0% of PC occurred synchronously. Thirty-five patients (87.5%) were assessable and exhibited measurable lesions. Two patients (5.7%) demonstrated complete response and five patients (14.3%) showed partial response. The median time to progression was 4.4 months (95% confidence interval, 2.5 to 6.3 months), the median overall survival time was 21.5 months (95% confidence interval, 17.2 to 25.7 months). There was no treatment related death. Presence of liver metastasis (p=0.022), performance status (p=0.039), and carcinoembryonic antigen level (p=0.016) were related to the time to progression. Patients with low carcinoembryonic antigen level (37.2 months vs. 15.6 months, p=0.001) or good performance status (22.5 months vs. 6.8 months, p=0.040) showed better overall survival. CONCLUSION: The m-FOLFOX4 regimen was determined to be effective for CRC patients with PC.
Carcinoembryonic Antigen ; Carcinoma ; Cause of Death ; Colorectal Neoplasms ; Fluorouracil ; Humans ; Leucovorin ; Liver ; Neoplasm Metastasis ; Organoplatinum Compounds ; Peritoneum

We report a case of Langerhans cell sarcoma presented as a solitary mass in the left supraclavicular area in a 31-year-old woman. Computed tomography revealed a relatively well-defined and lightly enhancing mass in the left supraclavicular area, measuring 5.5x4.5x3.2 cm. Excision was subsequently performed. Microscopically, the specimen consisted of an enlarged and partially effaced lymph node. Nests of different size composed of atypical tumor cells were located in the paracortex and the medulla of the lymph node. The tumor cells exhibited abundant eosinophilic or clear cytoplasm and displayed marked nuclear atypia and increased mitotic figures. Infiltration of many eosinophils was identified in the periphery and between the tumor cells. The tumor cells were reactive for CD1a and S100 protein. Ultrastructually, they were found to have Birbeck granules in the cytoplasm.
Adult ; Antigens, CD1 ; Cytoplasm ; Eosinophils ; Female ; Humans ; Langerhans Cell Sarcoma ; Lymph Nodes

PURPOSE: The role of first-line trastuzumab-based therapy has been firmly established in patients with human epidermal growth factor receptor-2 (HER2) positive metastatic breast cancer. In this trial, we evaluated the efficacy and safety of a vinorelbine and trastuzumab combination chemotherapy in patients who were pretreated with anthracyclines and taxanes. METHODS: Thirty-three patients with HER2 overexpressing metastatic breast cancer, all of whom had previously been treated with anthracyclines and taxanes, were included in this study. The patients were treated with 25 mg/m2 of vinorelbine (over a 15-minute infusion) on days 1 and 8 every 3 weeks. Additionally, trastuzumab was administered at an initial dose of 4 mg/kg over 90 minutes, and was subsequently administered at weekly doses of 2 mg/kg (over 30 minutes). RESULTS: The median age of the patients was 53 years (range, 39-72 years). The overall response rate was 30.3% (10 patients; 95% confidence interval [CI], 23-57%). The median time to progression was 6.8 months (95% CI, 5.3-8.2 months). The median overall survival was 12.4 months (95% CI, 10.3-14.6 months). In the 194 cycles of treatment, the incidence rates of grade > or =3 neutropenia and anemia were 7.2% and 1.0%, respectively. Neutropenic fever was detected in three cycles (1.5%). The non-hematological toxicities were not severe: grade 1 or 2 nausea or vomiting was detected in 15.2%, and grade 2 neuropathy was noted in 6.1% of patients. None of the patients experienced any serious cardiac toxicity, and no treatment-related deaths occurred. CONCLUSION: These results show that a combination chemotherapy consisting of vinorelbine and trastuzumab is useful in patients with HER2-overexpressing metastatic breast cancer who were pretreated with anthracyclines and taxanes, with a favorable toxicity profile.
Anemia ; Anthracyclines ; Antibodies, Monoclonal, Humanized ; Breast ; Breast Neoplasms ; Drug Therapy, Combination ; Epidermal Growth Factor ; Fever ; Humans ; Incidence ; Nausea ; Neoplasm Metastasis ; Neutropenia ; Taxoids ; Vinblastine ; Vomiting ; Trastuzumab