Objectives: To involve institutions without the ability to perform susceptibility testing, long-term storage of tissue sample is critical to isolate the bacteria in a central laboratory. The aim of the study was to investigate the feasibility of H. pylori isolation and antibiotic susceptibility testing using rapidly frozen biopsy specimens collected from various institutions. Methods: Eight institutions located in various regions of Korea participated in the study. Patients requiring upper endoscopy and H. pylori testing were screened. Two biopsy samples were taken from the stomach. One was placed in a sterile Eppendorf tube and then immediately placed in a vacuum bottle containing dry ice, which was stored at -80°C. The other was used in a rapid urease test. Collected samples were delivered to a central laboratory. The bacteria were isolated from the frozen samples under microaerophilic conditions. The agar dilution method was used to determine the minimum inhibitory concentration (MIC) of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate. Results: Patients with a positive rapid urease test result (n=113) were enrolled. The mean age was 56.6±12.3 years. The male:female ratio was 64:49. The overall culture success rate was 77.0% (87/113). MIC values were determined using isolated 87 H. pylori strains. Rates of resistance to amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, and ciprofloxacin were 23.0%, 25.3%, 28.7%, 1.1%, 33.3%, and 34.5%, respectively. Conclusions It is feasible to perform H. pylori isolation and antimicrobial susceptibility testing using rapidly frozen and transported biopsy specimens.

Objectives: To involve institutions without the ability to perform susceptibility testing, long-term storage of tissue sample is critical to isolate the bacteria in a central laboratory. The aim of the study was to investigate the feasibility of H. pylori isolation and antibiotic susceptibility testing using rapidly frozen biopsy specimens collected from various institutions. Methods: Eight institutions located in various regions of Korea participated in the study. Patients requiring upper endoscopy and H. pylori testing were screened. Two biopsy samples were taken from the stomach. One was placed in a sterile Eppendorf tube and then immediately placed in a vacuum bottle containing dry ice, which was stored at -80°C. The other was used in a rapid urease test. Collected samples were delivered to a central laboratory. The bacteria were isolated from the frozen samples under microaerophilic conditions. The agar dilution method was used to determine the minimum inhibitory concentration (MIC) of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate. Results: Patients with a positive rapid urease test result (n=113) were enrolled. The mean age was 56.6±12.3 years. The male:female ratio was 64:49. The overall culture success rate was 77.0% (87/113). MIC values were determined using isolated 87 H. pylori strains. Rates of resistance to amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, and ciprofloxacin were 23.0%, 25.3%, 28.7%, 1.1%, 33.3%, and 34.5%, respectively. Conclusions It is feasible to perform H. pylori isolation and antimicrobial susceptibility testing using rapidly frozen and transported biopsy specimens.

Objectives: To involve institutions without the ability to perform susceptibility testing, long-term storage of tissue sample is critical to isolate the bacteria in a central laboratory. The aim of the study was to investigate the feasibility of H. pylori isolation and antibiotic susceptibility testing using rapidly frozen biopsy specimens collected from various institutions. Methods: Eight institutions located in various regions of Korea participated in the study. Patients requiring upper endoscopy and H. pylori testing were screened. Two biopsy samples were taken from the stomach. One was placed in a sterile Eppendorf tube and then immediately placed in a vacuum bottle containing dry ice, which was stored at -80°C. The other was used in a rapid urease test. Collected samples were delivered to a central laboratory. The bacteria were isolated from the frozen samples under microaerophilic conditions. The agar dilution method was used to determine the minimum inhibitory concentration (MIC) of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate. Results: Patients with a positive rapid urease test result (n=113) were enrolled. The mean age was 56.6±12.3 years. The male:female ratio was 64:49. The overall culture success rate was 77.0% (87/113). MIC values were determined using isolated 87 H. pylori strains. Rates of resistance to amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, and ciprofloxacin were 23.0%, 25.3%, 28.7%, 1.1%, 33.3%, and 34.5%, respectively. Conclusions It is feasible to perform H. pylori isolation and antimicrobial susceptibility testing using rapidly frozen and transported biopsy specimens.

Objectives: To involve institutions without the ability to perform susceptibility testing, long-term storage of tissue sample is critical to isolate the bacteria in a central laboratory. The aim of the study was to investigate the feasibility of H. pylori isolation and antibiotic susceptibility testing using rapidly frozen biopsy specimens collected from various institutions. Methods: Eight institutions located in various regions of Korea participated in the study. Patients requiring upper endoscopy and H. pylori testing were screened. Two biopsy samples were taken from the stomach. One was placed in a sterile Eppendorf tube and then immediately placed in a vacuum bottle containing dry ice, which was stored at -80°C. The other was used in a rapid urease test. Collected samples were delivered to a central laboratory. The bacteria were isolated from the frozen samples under microaerophilic conditions. The agar dilution method was used to determine the minimum inhibitory concentration (MIC) of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate. Results: Patients with a positive rapid urease test result (n=113) were enrolled. The mean age was 56.6±12.3 years. The male:female ratio was 64:49. The overall culture success rate was 77.0% (87/113). MIC values were determined using isolated 87 H. pylori strains. Rates of resistance to amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, and ciprofloxacin were 23.0%, 25.3%, 28.7%, 1.1%, 33.3%, and 34.5%, respectively. Conclusions It is feasible to perform H. pylori isolation and antimicrobial susceptibility testing using rapidly frozen and transported biopsy specimens.

Objectives: To involve institutions without the ability to perform susceptibility testing, long-term storage of tissue sample is critical to isolate the bacteria in a central laboratory. The aim of the study was to investigate the feasibility of H. pylori isolation and antibiotic susceptibility testing using rapidly frozen biopsy specimens collected from various institutions. Methods: Eight institutions located in various regions of Korea participated in the study. Patients requiring upper endoscopy and H. pylori testing were screened. Two biopsy samples were taken from the stomach. One was placed in a sterile Eppendorf tube and then immediately placed in a vacuum bottle containing dry ice, which was stored at -80°C. The other was used in a rapid urease test. Collected samples were delivered to a central laboratory. The bacteria were isolated from the frozen samples under microaerophilic conditions. The agar dilution method was used to determine the minimum inhibitory concentration (MIC) of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate. Results: Patients with a positive rapid urease test result (n=113) were enrolled. The mean age was 56.6±12.3 years. The male:female ratio was 64:49. The overall culture success rate was 77.0% (87/113). MIC values were determined using isolated 87 H. pylori strains. Rates of resistance to amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, and ciprofloxacin were 23.0%, 25.3%, 28.7%, 1.1%, 33.3%, and 34.5%, respectively. Conclusions It is feasible to perform H. pylori isolation and antimicrobial susceptibility testing using rapidly frozen and transported biopsy specimens.

Purpose: This study aimed to compare the characteristics of venous thromboembolic disease (VTE) in Korean to Caucasian population. Materials and Methods: XALIA-LEA and XALIA were phase IV non-interventional prospective studies with identical designs that investigated the effect of rivaroxaban versus standard anticoagulation for VTE. Koreans accounted for the largest proportion of the overall enrolled population of XALIA-LEA. However, in the XALIA study, most patients were Caucasian. Therefore, Korean data from XALIA-LEA and Caucasian data from XALIA were used in this study. This study compared the clinical characteristics and primary outcomes of the XALIA program, including major bleeding, recurrent VTE, and all-cause mortality. Results: The Korean population was older, was less obese, and had more active cancer at baseline than the Caucasian population. Provoked VTE was more common in the Korean population. Interestingly, Koreans showed less accompanying thrombophilia than Caucasians, and factor V Leiden mutations were not detected. Korean analyses comparing the effects of rivaroxaban and standard anticoagulation with primary outcomes showed a lower incidence of major bleeding, recurrent VTE, and all-cause mortality with rivaroxaban. Similar results were obtained in the propensity score matching analysis. Conclusion Characteristic differences were found between Korean and Caucasian VTE patients. Despite these ethnic differences, the effectiveness and safety of rivaroxaban therapy in these patients were consistent.

Background: Coronavirus disease 2019 (COVID-19) has spread around the globe, and it is important to determine the risk factors of death in the general population. Our study aimed to determine the risk factors of death and severe illness requiring supplemental oxygen therapy based on the demographic and clinical characteristics of COVID-19 patients in Korea. Methods: In this study, we used data provided by the Korea Disease Control and Prevention Agency (KDCA) and analyzed a total of 5,068 patients with COVID-19, excluding 19 pregnant women and 544 individuals with missing data. We performed logistic regression analysis to determine the impact of early symptoms on survival and severe disease. Logistic regression models included sex, age, number of comorbidities, symptoms on admission, blood pressure, heart rate, and body temperature as explanatory variables, and death and oxygen therapy as outcome variables. Results: Logistic regression analyses revealed that the male sex, older age (≥ 60 years), higher number of comorbidities, presence of symptoms on admission, heart rate ≥ 120 bpm, and body temperature ≥ 37.5°C presented with higher risk of in-hospital death and oxygen therapy requirement. Conversely, rhinorrhea and headache were associated with a low risk of death and oxygen therapy requirement. The findings showed that cough, sputum, and fever were the most common symptoms on admission, while 25.3% of patients with COVID-19 were asymptomatic. Conclusion COVID-19 patients with high-risk early symptoms on admission, such as dyspnea and altered mental status, and those without low-risk symptoms of rhinorrhea and headache should be included in priority treatment groups.

Background: Coronavirus disease 2019 (COVID-19) has spread around the globe, and it is important to determine the risk factors of death in the general population. Our study aimed to determine the risk factors of death and severe illness requiring supplemental oxygen therapy based on the demographic and clinical characteristics of COVID-19 patients in Korea. Methods: In this study, we used data provided by the Korea Disease Control and Prevention Agency (KDCA) and analyzed a total of 5,068 patients with COVID-19, excluding 19 pregnant women and 544 individuals with missing data. We performed logistic regression analysis to determine the impact of early symptoms on survival and severe disease. Logistic regression models included sex, age, number of comorbidities, symptoms on admission, blood pressure, heart rate, and body temperature as explanatory variables, and death and oxygen therapy as outcome variables. Results: Logistic regression analyses revealed that the male sex, older age (≥ 60 years), higher number of comorbidities, presence of symptoms on admission, heart rate ≥ 120 bpm, and body temperature ≥ 37.5°C presented with higher risk of in-hospital death and oxygen therapy requirement. Conversely, rhinorrhea and headache were associated with a low risk of death and oxygen therapy requirement. The findings showed that cough, sputum, and fever were the most common symptoms on admission, while 25.3% of patients with COVID-19 were asymptomatic. Conclusion COVID-19 patients with high-risk early symptoms on admission, such as dyspnea and altered mental status, and those without low-risk symptoms of rhinorrhea and headache should be included in priority treatment groups.

Background: Hürthle cell carcinoma (HCC), a type of thyroid carcinoma, is rare in South Korea, and few studies have investigated its prognosis. Methods: This long-term multicenter retrospective cohort study evaluated the clinicopathological features and clinical outcomes in patients with HCC who underwent thyroid surgery between 1996 and 2009. Results: The mean age of the 97 patients included in the study was 50.3 years, and 26.8% were male. The mean size of the primary tumor was 3.2±1.8 cm, and three (3.1%) patients had distant metastasis at initial diagnosis. Ultrasonographic findings were available for 73 patients; the number of nodules with low-, intermediate-, and high suspicion was 28 (38.4%), 27 (37.0%), and 18 (24.7%), respectively, based on the Korean-Thyroid Imaging Reporting and Data System. Preoperatively, follicular neoplasm (FN) or suspicion for FN accounted for 65.2% of the cases according to the Bethesda category, and 13% had malignancy or suspicious for malignancy. During a median follow-up of 8.5 years, eight (8.2%) patients had persistent/recurrent disease, and none died of HCC. Older age, gross extrathyroidal extension (ETE), and widely invasive types of tumors were significantly associated with distant metastasis (all P<0.01). Gross ETE (hazard ratio [HR], 27.7; 95% confidence interval [CI], 2.2 to 346.4; P=0.01) and widely invasive classification (HR, 6.5; 95% CI, 1.1 to 39.4; P=0.04) were independent risk factors for poor disease-free survival (DFS). Conclusion The long-term prognosis of HCC is relatively favorable in South Korea from this study, although this is not a nation-wide data, and gross ETE and widely invasive cancer are significant prognostic factors for DFS. The diagnosis of HCC by ultrasonography and cytopathology remains challenging.

BACKGROUND: Concerns have arisen about the classification of extra-thyroidal extension (ETE) and lateral cervical lymph node metastasis (N1b) in the 8th edition of the tumor-node-metastasis staging system (TNM-8). This study evaluated the prognostic validity of a modified-TNM staging system, focusing on ETE and N1b, in differentiated thyroid carcinoma (DTC) patients. METHODS: This multicenter retrospective cohort study included 4,878 DTC patients from five tertiary hospitals. In the modified-TNM, T3b in TNM-8 was down-staged to T2, and stage II was subdivided into stages IIA and IIB. Older patients with N1b were reclassified as stage IIB. RESULTS: The modified-TNM resulted in staging migration in 540 patients (11%) classified as stage II according to the TNM-8, with 75 (14%), 381 (71%), and 84 patients (16%) classified as stages I, IIA, and IIB, respectively. The 10-year disease-specific survival (DSS) rates in patients classified as stages I, II, III, and IV by TNM-8 were 99.8%, 95.9%, 81.0%, and 41.6%, respectively. The DSS rates of patients classified as stages I, IIA, IIB, III, and IV according to the modified-TNM were 99.8%, 96.4%, 93.3%, 81.0%, and 41.6%, respectively. DSS curves between stages on TNM-8 (P<0.001) and modified-TNM (P<0.001) differed significantly, but the modified-TNM discriminated better than TNM-8. The proportions of variation explained values of TNM-8 and modified-TNM were 6.3% and 6.5%, respectively. CONCLUSION Modification of the TNM staging system focusing on ETE and N1b could improve the prediction of DSS in patients with DTC. Further researches are needed to validate the prognostic accuracy of this modified-TNM staging system.