Background and Objectives: The relationship between the hospital percutaneous coronary intervention (PCI) volumes and the in-hospital clinical outcomes of patients with acute myocardial infarction (AMI) remains the subject of debate. This study aimed to determine whether the in-hospital clinical outcomes of patients with AMI in Korea are significantly associated with hospital PCI volumes. Methods: We selected and analyzed 17,121 cases of AMI, that is, 8,839 cases of non-ST-segment elevation myocardial infarction and 8,282 cases of ST-segment elevation myocardial infarction, enrolled in the 2014 Korean percutaneous coronary intervention (K-PCI) registry. Patients were divided into 2 groups according to hospital annual PCI volume, that is, to a high-volume group (≥400/year) or a low-volume group (<400/year). Major adverse cardiovascular and cerebrovascular events (MACCEs) were defined as composites of death, cardiac death, non-fatal myocardial infarction (MI), stent thrombosis, stroke, and need for urgent PCI during index admission after PCI. Results: Rates of MACCE and non-fatal MI were higher in the low-volume group than in the high-volume group (MACCE: 10.9% vs. 8.6%, p=0.001; non-fatal MI: 4.8% vs. 2.6%, p=0.001, respectively). Multivariate regression analysis showed PCI volume did not independently predict MACCE. Conclusions Hospital PCI volume was not found to be an independent predictor of in-hospital clinical outcomes in patients with AMI included in the 2014 K-PCI registry.

PURPOSE: Tenofovir disoproxil fumarate (TDF) is commonly prescribed as a fixed-dose, co-formulated antiretroviral drug for HIV-1 infection. The major concern of long-term TDF use is renal dysfunction. However, little is known about the long-term patterns of changes in renal function in HIV-infected Koreans receiving TDF. MATERIALS AND METHODS: We prospectively followed 50 HIV-infected Koreans, performing laboratory tests every 3 months during the first year and every 6 months for the next 2 years. Urine N-acetyl-β-D-glucosaminidase (NAG) and plasma cystatin-C were measured using samples collected in the first year. Data on renal function were retrospectively collected on HIV-infected patients receiving first-line TDF (n=40) and in antiretroviral therapy (ART)-naïve patients (n=24) for 3 years. Renal function was evaluated as estimated glomerular filtration rate (eGFR) from serum creatinine [Modification of Diet in Renal Disease (MDRD)] and cystatin-C. RESULTS: The eGFR (cystatin-C) showed significant changes from 0 to 48 wks (p=0.002), with the lowest levels at 24 wks (84.3±18.8 mL/min vs. 90.3±22.5 mL/min, p=0.021 by post hoc test). Urine NAG levels did not differ at 0, 12, 24, and 48 wks, although eGFR (MDRD) significantly decreased from 0 (98.7±18.9 mL/min/1.73 m²) to 144 wks (89.0±14.7 mL/min/1.73 m²) (p=0.010). The first-line TDF group had significantly lower eGFR (MDRD) than the ART-naïve group at 144 wks (89.7 mL/min/1.73 m² vs. 98.4 mL/min/1.73 m², p=0.036). Thirteen (26%) participants experienced a decrease in renal impairment of 10 mL/min/1.73 m² in eGFR (MDRD) at 144 wks. CONCLUSION: These data suggest that clinically meaningful renal injury can develop in HIV-infected Koreans receiving long-term TDF.
Creatinine ; Diet ; Follow-Up Studies* ; Glomerular Filtration Rate ; HIV ; HIV-1 ; Humans ; Plasma ; Prospective Studies ; Retrospective Studies ; Tenofovir*

BACKGROUND: Pyridoxal-5'-phosphate (P5P), a coenzyme of the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) reactions, is required to measure aminotransferase levels (IFCC method). However, a modified IFCC method that uses a reagent devoid of P5P is commonly used in laboratories in Korea. To determine the differences between the two methods, we compared aminotransferase levels measured by using the IFCC method and modified IFCC method. METHODS: Serum levels of AST and ALT, with and without P5P, were measured in 2,318 patients. Based on the allowable limits of performance set by the Royal College of Pathologists of Australasia (RCPA), differences between the two methods were analyzed under various conditions. RESULTS: Higher AST and ALT values were obtained by the IFCC method compared to modified IFCC method, showing significant differences between the two methods (AST, 5.8±14.2 IU/L; ALT, 2.8±6.9 IU/L) (P<0.001). Values exceeding RCPA criteria were more frequently observed in emergency orders (AST, 65.8%; ALT, 14.4%) than in routine orders (AST, 3.2%; ALT, 9.6%), as well as in inpatient wards (AST, 70.4%; ALT, 18.5%) compared to outpatient clinics (AST, 56.6%; ALT, 10.0%). However, the differences between the two methods were not significant among the disease groups, except for the acute myocardial infarction group. CONCLUSIONS: The method using reagents without P5P underestimated aminotransferase activity. The effect of P5P was more significant in patients with acute myocardial infarction, considered as P5P-deficient. In conclusion, the IFCC method with P5P should be applied for measuring AST and ALT serum levels.
Alanine Transaminase ; Ambulatory Care Facilities ; Aspartate Aminotransferases ; Australasia ; Emergencies ; Humans ; Indicators and Reagents ; Inpatients ; Korea ; Liver Function Tests ; Methods ; Myocardial Infarction ; Pyridoxal Phosphate

PURPOSE: Pentraxin 3 (PTX3) has been suggested to be a prognostic marker of mortality in severe sepsis. Currently, there are limited data on biomarkers including PTX3 that can be used to predict mortality in severe sepsis patients who have undergone successful initial resuscitation through early goal-directed therapy (EGDT). MATERIALS AND METHODS: A prospective cohort study was conducted among 83 severe sepsis patients with fulfillment of all EGDT components and the achievement of final goal. Plasma PTX3 levels were measured by sandwich ELISA on hospital day (HD) 0, 3, and 7. The data for procalcitonin, C-reactive protein and delta neutrophil index were collected by electric medical record. The primary outcome was 28-day all-cause mortality. RESULTS: 28-day all-cause mortality was 19.3% and the median (interquartile range) APHCH II score of total patients was 16 (13–19). The non-survivors (n=16) had significantly higher PTX3 level at HD 0 [201.4 (56.9–268.6) ng/mL vs. 36.5 (13.7–145.3) ng/mL, p=0.008]. PTX3 had largest AUC(ROC) value for the prediction of mortality among PTX3, procalcitonin, delta neutrophil index, CRP and APACHE II/SOFA sore at HD 0 [0.819, 95% confidence interval (CI) 0.677–0.961, p=0.008]. The most valid cut-off level of PTX3 at HD 0 was 140.28 ng/mL (sensitivity 66.7%, specificity 73.8%). The PTX3 and procalcitonin at HD 0 showed strong correlation (r=0.675, p<0.001). However, PTX3 at HD 0 was the only independent predictive marker in Cox's proportional hazards model (≥140 ng/mL; hazard rate 7.16, 95% CI 2.46–15.85, p=0.001). CONCLUSION: PTX3 at HD 0 could be a powerful predictive biomarker of 28-day all-cause mortality in severe septic patients who have undergone successful EGDT.
APACHE ; Biomarkers ; C-Reactive Protein ; Cohort Studies ; Enzyme-Linked Immunosorbent Assay ; Humans ; Medical Records ; Mortality* ; Neutrophils ; Plasma ; Proportional Hazards Models ; Prospective Studies ; Resuscitation ; Sensitivity and Specificity ; Sepsis

BACKGROUND: The hemoglobin A1c (HbA1c) level is widely used to diagnose and monitor glycaemic control in people with diabetes mellitus, and various methods are used for its determination. The D-100 hemoglobin testing system (Bio-Rad Laboratories, USA) is a fully automated, high-throughput glycohaemoglobin analyzer based on an ion-exchange high-performance liquid chromatographic method. Here, we evaluated the analytical performance of a newly developed HbA1c analyzer. METHODS: Precision, linearity, and comparison to the Variant II Turbo analyzer (Bio-Rad Laboratories, USA) were evaluated according to the Clinical Laboratory Standards Institute guidelines. Carryover, bias from the value assigned by the HbA1c Network Laboratory of Korea Centers for Disease Control and Prevention, and the vulnerability to interference by hemoglobin variants frequently found in Korea were also assessed. Statistical analyses were performed using Excel 2010 (Microsoft Co., USA) and MedCalc ver. 14.12.0 (MedCalc Software bvba, Belgium). RESULTS: The coefficients of variation for repeatability and within-device precision were less than 1.08% in National Glycohaemoglobin Standardization Program (NGSP) unit and less than 1.68% in international system of unit at all three levels. The calibration curve was linear, with R²=0.996 in the range of 4.6% to 15.4% in NGSP unit. The results highly correlated with those produced by Variant II Turbo (r=0.998). The 95% confidence interval for differences from the assigned values was -3.3% to 2.9%. No significant interferences of haemoglobin variants were observed except for Hemoglobin Yamagata. CONCLUSIONS: The D-100 hemoglobin testing system showed excellent precision, linearity, and good correlation with the Variant II Turbo analyzer and agreement with the assigned values. Therefore, its analytical performance is satisfactory for diabetes diagnosis and treatment monitoring.
Bias (Epidemiology) ; Calibration ; Centers for Disease Control and Prevention (U.S.) ; Diabetes Mellitus ; Diagnosis ; Hemoglobin A, Glycosylated ; Korea ; Methods

We report here the results of the external quality assessment scheme (EQA) of blood bank tests in Korea carried out in 2015. The proficiency testing specimens used in the survey were prepared at Ajou University Hospital. The response rates from participating laboratories for the first and second trials were 98.7% (542/549) and 98.2% (544/554), respectively. No answers to tests were considered incorrect, and the average accuracy rates for six different test items on the standard survey were as follows: ABO grouping, 99.4% to 100.0%; RhD typing, 99.4% to 100.0%; crossmatching, 93.6% to 99.0%; direct antiglobulin test (DAT) using a polyspecific reagent, 92.9% to 98.3%; DAT using an IgG monospecific reagent, 94.6% to 100.0%; DAT using a C3d monospecific reagent, 84.2% to 98.6%; unexpected antibody screening test, 94.5% to 100.0%; and antibody identification test, 93.8% to 100.0%. We performed a pilot survey on reactivities to A1 (54 responses) and H (50 responses); Rh C, c, E, and e antigen testing (47 responses); and ABO antibody titration (10-34 responses). We obtained excellent results for this EQA, and these results will be helpful for improving or maintaining the quality of the participating laboratories.
Blood Banks* ; Coombs Test ; Immunoglobulin G ; Korea* ; Laboratory Proficiency Testing ; Mass Screening

As dried blood spots (DBSs) have various advantages over conventional venous blood sampling, some assays for detection of one or two anti-tuberculosis (TB) drugs in DBSs have been developed. However, there are no assays currently available for the simultaneous measurement of three or more anti-TB drugs in DBSs. In this study, we developed and evaluated a multiplex method for detecting nine anti-TB drugs including streptomycin, kanamycin, clarithromycin, cycloserine, moxifloxacin, levofloxacin, para-aminosalicylic acid, prothionamide, and linezolid in DBSs by using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Seventy-nine patient samples of DBS were analyzed on the UPLC-MS/MS system. All drug concentrations were determined within 4 min, and assay performance was evaluated. All drugs were clearly separated without ion suppression. Within-run and between-run precisions were 1.7-13.0% and 5.7-17.0%, respectively, at concentrations representing low and high levels for the nine drugs. Lower limits of detection and quantification were 0.06-0.6 and 0.5-5.0 µg/mL, respectively. Linearity was acceptable at five level concentrations for each drug. Correlations between drug concentrations in plasma and DBSs by using Passing-Bablock regression and Pearson's rho (ρ, 0.798-0.989) were acceptable. In conclusion, we developed a multiplex assay to measure nine second-line anti-TB drugs in DBSs successfully. This assay provided convenient and rapid drug quantification and could have applications in drug monitoring during treatment.
Antitubercular Agents/*blood ; Chromatography, High Pressure Liquid ; *Dried Blood Spot Testing ; Humans ; Limit of Detection ; Reproducibility of Results ; *Tandem Mass Spectrometry

No abstract available.
Adult ; Cerebroside-Sulfatase/*metabolism ; Child, Preschool ; *Chromatography, High Pressure Liquid ; Enzyme Assays/instrumentation/*methods ; Female ; Humans ; Kinetics ; Leukocytes/*enzymology ; Leukodystrophy, Metachromatic/diagnosis/enzymology ; Male ; Middle Aged ; Reference Standards ; Substrate Specificity ; Sulfoglycosphingolipids/analysis/metabolism/standards ; *Tandem Mass Spectrometry/standards

We report here the results of surveys on external quality assessment (EQA) of blood bank tests in Korea carried out in 2014. The proficiency testing specimens were prepared at Ajou University Hospital and the response rates for the 1st and 2nd trials were 94.3% (537/549) and 96.0% (545/554), respectively. No answers were considered incorrect, and the average accuracy rates of six different test items on the regular survey were as follows: ABO grouping, 98.5% to 100.0%; RhD typing, 98.1% to 99.4%; crossmatching, 91.2% to 99.6%; direct antiglobulin test (DAT) using a polyspecific reagent, 96.7% to 98.4%; DAT using an immunoglobulin-G monospecific reagent, 93.8% to 98.7%; DAT using a C3d monospecific reagent, 89.5% to 98.7%; unexpected antibody screening test, 96.2% to 100.0%; and antibody identification test, 69.8% to 100.0%. Test items for the pilot survey were reactivities to anti-A1 and anti-H, Rh subgrouping, and ABO antibody titration. Except for the result of the antibody identification test for specimens with multiple antibodies, we obtained excellent survey results for the EQA of blood bank tests carried out in 2014. In addition, the number of participating institutes was higher in 2014 than in 2013. The EQA of blood bank tests in 2014 should be helpful for improving the quality of the participating laboratories.
Academies and Institutes ; Antibodies ; Blood Banks ; Coombs Test ; Korea ; Laboratory Proficiency Testing ; Mass Screening

We evaluated the urinary glucose tetrasaccharide (Glc4) assay using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The calibration curve was linear over a range of 5-500 micromol/L. Performance parameters such as intra- and inter-day imprecision CVs were 6.52-14.6% and 11.5-13.2%, respectively. The mean concentrations of urinary Glc4 in 27 normal controls and 3 pseudodeficiency patients were 1.5 and 12.1 mmol/mol creatinine, respectively. Urinary Glc4 concentration in a patient with Pompe disease was 171.3 mmol/mol creatinine, which decreased to 130.9 mmol/mol following enzyme replacement therapy. Based on our results, we suggest that the urinary Glc4 assay using UPLC-MS/MS can be a reliable diagnostic tool for identification of patients with Pompe disease.
Calibration ; Creatinine ; Diagnosis* ; Enzyme Replacement Therapy ; Glucose* ; Glycogen Storage Disease Type II* ; Humans ; Mass Spectrometry*