BACKGROUND: Cardiovascular disease is the major cause of mortality in patients receiving hemodialysis(HD) for end stage renal disease(ESRD). After renal failure, antioxidant levels increase, possibly in response to increased generation of free radicals. As a result, increased lipid peroxidation may contribute to increased risks of atherosclerosis. The aims of this study was to investigate the distribution of total antioxidant capacity of plasma in Korean adults and ESRD patients, and effects of HD. METHODS: Ninety five patients(41 men and 54 women, mean ages 54.7+/-28.3 years) receiving regular HD for ESRD were recruited. Venous blood samples were taken immediately before HD in 65 patients, and before and after HD in 30 patients. Control subjects were healthy individuals(61 men and 51 women, mean ages 42.7+/-10.8 years). Total antioxidant capacity of plasma and serum uric acid concentration were assessed. RESULTS: Reference range of plasma total antioxidant capacity in Korean population is 1.04 ~ 1.52 mmol/L. Total antioxidant capacities in male(1.32+/-0.11 mmol/L; mean+/-SD) were higher than those of female(1.24+/-0.12 mmol/L, P<0.001). Total antioxidant capacities in ESRD patients(1.72+/-0.26 mmol/L) were higher than controls(1.28+/-0.12 mmol/L, P<0.001). Total antioxidant capacities in pre-HD samples(1.55+/-0.16 mmol/L) were higher than post-HD(1.33+/-0.10 mmol/L). Plasma total antioxidant capacities and serum uric acid concentrations showed positive correlation(r = 0.69, P < 0.0001). DISCUSSION: The increase in total antioxidant capacity in ESRD patients might be due to high serum uric acid. Plasma total antioxidant capacities decreased after HD in ESRD patients due to decrease of uric acid concentration.
Adult ; Atherosclerosis ; Cardiovascular Diseases ; Female ; Free Radicals ; Humans ; Kidney Failure, Chronic* ; Lipid Peroxidation ; Male ; Mortality ; Plasma ; Reference Values ; Renal Dialysis* ; Renal Insufficiency ; Uric Acid

No abstract available.
*Algorithms ; Automation ; Clinical Laboratory Information Systems/*standards ; Humans ; Immunoassay/*methods ; Indicator Dilution Techniques ; alpha-Fetoproteins/*analysis

INTRODUCTION: Hypomagnesemia, major cause of hypocalcemia, is developed due to insufficient oral intake in hospitalized patient and high prevalence in intensive care unit (ICU) patient. It is important to monitoring ionized magnesium in ICU patient because hypomagnesemia has been implicated in the development of cardiovascular dysfunction. So, in this study we determine the relation between ionized calcium and ionized magnesium and validate the measurement of ionized magnesium. MATERIAL AND METHOD: From March 2005 to may 2005, total 2876 samples were enrolled, which was requested to measure ionized calcium. We measured ionized calcium and ionized magnesium using NOVA CCX (Nova Biomedical, Waltman, MA, USA). Reference range of ionized calcium and ionized magnesium was 3.9~4.5 and 1.1~1.5 mg/dL, respectively. The patients were grouped as adult above 18 years old and pediatric below 18 years old. The ward was intensive care unit (ICU), general ward, outpatient and emergency room. We investigate the frequency of hypocalcemia and hypomagnesemia. RESULTS: The prevalence of ionized hypocalcemia (Ca2+ < 3.9mg/dL) was 22.2% and the prevalence of ionized hypomagnesemia (Mg2+ < 1.1mg/dL) was 41.9%. Of 2876 samples, 377 samples had ionized hypocalcemia and ionized hypomagnesemia simultaneously. Fifty-nine percent samples showing ionized hypocalcemia had ionized hypomagnesemia. In pediatric patients 13.3% of all patients had ionized hypocalcemia, 20.0% showing ionized hypercalcemia and 37.6% showing ionized hypomagnesemia. In adult patients 24.3% of all patients had ionized hypocalcemia, 14.3% showing ionized hypercalcemia, 48.2% showing ionized hypomagnesemia and one patient had ionized hypermagnesemia. When considering total cases of ionized calcium, the average level of ionized calcium was lowest in emergency room. When considering in case of patients, ICU showed the lowest level of ionized calcium. CONCLUSION: Ionized hypomagnesemia had known to be one of the major causes of ionized hypocalcemia and is common in ionized hypocalcemia. It is easy to found by measuring simultaneously. We found high coincidence rate of ionized hypocalcemia and ionized hypomagnesemia. We recommend that all samples ordered to be measuring ionized calcium must be checked ionized magnesium simultaneously.
Adolescent ; Adult ; Calcium ; Emergency Service, Hospital ; Humans ; Hypercalcemia ; Hypocalcemia* ; Intensive Care Units ; Magnesium ; Outpatients ; Patients' Rooms ; Prevalence ; Reference Values

BACKGROUND: Many laboratories use 4 delta check methods: delta difference, delta percent change, rate difference, and rate percent change. However, guidelines regarding decision criteria for selecting delta check methods have not yet been provided. We present new decision criteria for selecting delta check methods for each clinical chemistry test item. METHODS: We collected 811,920 and 669,750 paired (present and previous) test results for 27 clinical chemistry test items from inpatients and outpatients, respectively. We devised new decision criteria for the selection of delta check methods based on the ratio of the delta difference to the width of the reference range (DD/RR). Delta check methods based on these criteria were compared with those based on the CV% of the absolute delta difference (ADD) as well as those reported in 2 previous studies. RESULTS: The delta check methods suggested by new decision criteria based on the DD/RR ratio corresponded well with those based on the CV% of the ADD except for only 2 items each in inpatients and outpatients. Delta check methods based on the DD/RR ratio also corresponded with those suggested in the 2 previous studies, except for 1 and 7 items in inpatients and outpatients, respectively. CONCLUSIONS: The DD/RR method appears to yield more feasible and intuitive selection criteria and can easily explain changes in the results by reflecting both the biological variation of the test item and the clinical characteristics of patients in each laboratory. We suggest this as a measure to determine delta check methods.
Alanine Transaminase/blood ; Alkaline Phosphatase/blood ; Aspartate Aminotransferases/blood ; Bilirubin/blood ; Blood Urea Nitrogen ; Chemoembolization, Therapeutic ; Clinical Chemistry Tests/methods/*standards ; Creatine/blood ; *Decision Trees ; Humans ; Reference Values ; Renal Dialysis ; Uric Acid/blood

BACKGROUND: Many laboratories use 4 delta check methods: delta difference, delta percent change, rate difference, and rate percent change. However, guidelines regarding decision criteria for selecting delta check methods have not yet been provided. We present new decision criteria for selecting delta check methods for each clinical chemistry test item. METHODS: We collected 811,920 and 669,750 paired (present and previous) test results for 27 clinical chemistry test items from inpatients and outpatients, respectively. We devised new decision criteria for the selection of delta check methods based on the ratio of the delta difference to the width of the reference range (DD/RR). Delta check methods based on these criteria were compared with those based on the CV% of the absolute delta difference (ADD) as well as those reported in 2 previous studies. RESULTS: The delta check methods suggested by new decision criteria based on the DD/RR ratio corresponded well with those based on the CV% of the ADD except for only 2 items each in inpatients and outpatients. Delta check methods based on the DD/RR ratio also corresponded with those suggested in the 2 previous studies, except for 1 and 7 items in inpatients and outpatients, respectively. CONCLUSIONS: The DD/RR method appears to yield more feasible and intuitive selection criteria and can easily explain changes in the results by reflecting both the biological variation of the test item and the clinical characteristics of patients in each laboratory. We suggest this as a measure to determine delta check methods.
Alanine Transaminase/blood ; Alkaline Phosphatase/blood ; Aspartate Aminotransferases/blood ; Bilirubin/blood ; Blood Urea Nitrogen ; Chemoembolization, Therapeutic ; Clinical Chemistry Tests/methods/*standards ; Creatine/blood ; *Decision Trees ; Humans ; Reference Values ; Renal Dialysis ; Uric Acid/blood

BACKGROUND: Neuron-specific enolase (NSE) is an enzyme specifically found in neurons and neuroendocrine tissue. It is a common marker for small cell lung cancer diagnosis and is also useful as a predictor of brain damage. This study evaluates the performance of Elecsys NSE (Roche Diagnostics, Switzerland), an electrochemiluminescent immunoassay. METHODS: The precision, linearity, limit of detection, and reference interval of the Elecsys NSE, as well as the correlation between Elecsys NSE and ELSA-NSE (Cis-Bio International, France) were evaluated in accordance with the Clinical Laboratory Standards Institute (CLSI) guidelines. PreciControl Tumor Marker (Roche Diagnostics), patient sera, and sera from healthy individuals were used for the analysis. RESULTS: The measured coefficient of variation for the assay was below 3%, and it demonstrated linearity from 0.20 to 234.5 ng/mL. The detection limit was 0.032 ng/mL and the reference interval ranged from 0.05 to 16.3 ng/mL. Compared with the ELSA-NSE assay, the correlation coefficient was 0.9128. CONCLUSIONS: The Elecsys assay showed suitable precision, linearity, limit of detection and reference range for clinical laboratory use; however, the correlation coefficient of Elecsys NSE as compared to ELSA-NSE was below 0.975. This result may be associated with the use of different monoclonal antibodies in the two different NSE assays. Elecsys NSE demonstrated a high sensitivity without the use of radioactive reagents; therefore, Elecsys NSE will be quite useful for NSE analysis in the clinical laboratory setting.
Antibodies, Monoclonal ; Brain ; Diagnosis ; Humans ; Immunoassay ; Indicators and Reagents ; Limit of Detection ; Neurons ; Phosphopyruvate Hydratase* ; Reference Values ; Small Cell Lung Carcinoma

BACKGROUND: Neuron-specific enolase (NSE) is an enzyme specifically found in neurons and neuroendocrine tissue. It is a common marker for small cell lung cancer diagnosis and is also useful as a predictor of brain damage. This study evaluates the performance of Elecsys NSE (Roche Diagnostics, Switzerland), an electrochemiluminescent immunoassay. METHODS: The precision, linearity, limit of detection, and reference interval of the Elecsys NSE, as well as the correlation between Elecsys NSE and ELSA-NSE (Cis-Bio International, France) were evaluated in accordance with the Clinical Laboratory Standards Institute (CLSI) guidelines. PreciControl Tumor Marker (Roche Diagnostics), patient sera, and sera from healthy individuals were used for the analysis. RESULTS: The measured coefficient of variation for the assay was below 3%, and it demonstrated linearity from 0.20 to 234.5 ng/mL. The detection limit was 0.032 ng/mL and the reference interval ranged from 0.05 to 16.3 ng/mL. Compared with the ELSA-NSE assay, the correlation coefficient was 0.9128. CONCLUSIONS: The Elecsys assay showed suitable precision, linearity, limit of detection and reference range for clinical laboratory use; however, the correlation coefficient of Elecsys NSE as compared to ELSA-NSE was below 0.975. This result may be associated with the use of different monoclonal antibodies in the two different NSE assays. Elecsys NSE demonstrated a high sensitivity without the use of radioactive reagents; therefore, Elecsys NSE will be quite useful for NSE analysis in the clinical laboratory setting.
Antibodies, Monoclonal ; Brain ; Diagnosis ; Humans ; Immunoassay ; Indicators and Reagents ; Limit of Detection ; Neurons ; Phosphopyruvate Hydratase* ; Reference Values ; Small Cell Lung Carcinoma

Herein, we report a case in which cholestasis caused discrepancy in high-density lipoprotein (HDL)-cholesterol levels measured using various methods. The discrepancy in HDL-cholesterol level originated from the abnormal increase in the level of an unusual lipoprotein, apo E-rich HDL, in the patient's serum. An abnormal slow alpha-migrating lipoprotein was observed on agarose gel electrophoresis, and an abnormal large-sized HDL was observed in a lipoprotein subfraction study. The level of apolipoprotein E was elevated.
Apolipoproteins ; Cholestasis ; Electrophoresis, Agar Gel ; Lipoproteins

Herein, we report a case in which cholestasis caused discrepancy in high-density lipoprotein (HDL)-cholesterol levels measured using various methods. The discrepancy in HDL-cholesterol level originated from the abnormal increase in the level of an unusual lipoprotein, apo E-rich HDL, in the patient's serum. An abnormal slow alpha-migrating lipoprotein was observed on agarose gel electrophoresis, and an abnormal large-sized HDL was observed in a lipoprotein subfraction study. The level of apolipoprotein E was elevated.
Apolipoproteins ; Cholestasis ; Electrophoresis, Agar Gel ; Lipoproteins

No abstract available.
Drug Monitoring ; Sirolimus ; Tacrolimus