Performance of the electrochemiluminescent immunoassay system of Elecsys 2010 was evaluated by quantitative assay. The functional sensitivity of the TSH assay was 0.004 microU/ml. The extra-assay imprecision was RSD = 1.45%-4.65% in the range of TSH concentrations of 0.43-88.15 microU/ml. The intra-assay imprecision was RSD = 1.38%-3.14% in the range of TSH concentrations of 0.41-87.28 microU/ml. The recovery of TSH was in the range of 98.6%-104.4%. The correlation between theoretical values and obtained values of TSH was adequate(r = 0.999). We conclude that the Elecsys 2010 is provably satisfactory in sensitivity, precision, accuracy, reliability, practicability and rapidity.
Electrochemistry ; instrumentation ; Evaluation Studies as Topic ; Humans ; Immunoassay ; instrumentation ; standards ; Luminescent Measurements ; Sensitivity and Specificity ; Thyrotropin ; blood

BACKGROUND: Due to the westernization of living environments in Korea, a number of allergy patients are greatly increasing. External quality control assessments are difficult for allergy tests due to the lack of reference methods. We surveyed the current status of allergy tests performed in medical laboratories in Korea to prepare for an external quality control assessment in the near future. METHODS: We conducted a survey on internal and external quality control trials, calibrations and its intervals, medical staffs, analyzers in use, an average number of tests per months, and report formats. RESULTS: Among the 85 laboratories surveyed, 61 were doing allergy tests including 6 reference laboratories. There were two different types of analyzers (1) qualitative or semi-quantitative and (2) quantitative. These analyzers use either chemiluminescent or immunoblot method. Fifty-five laboratories were using 'qualitative or semi-quantitative' analyzers as a screening test and 31 laboratories were using quantitative analyzers. Most of the laboratories were only doing an internal quality control assessment included in the test kits. Excepting a few laboratories, calibrations were not done. About 34 laboratories reported numerical values with interpretative reports prepared by laboratory medical doctors. CONCLUSIONS: The necessity of external quality control assessment has become an issue for improving the quality of allergy tests. But due to the lack of standardization, it is difficult to carry out external quality control assessments. By grouping the laboratories in terms of the type of analyzers, we could overcome the problem of analyzer variations and launch an external quality control assessment program in the near future.
Allergens/*immunology ; Chemiluminescent Measurements/standards ; Humans ; Immunoassay/instrumentation/*standards ; Immunoblotting/standards ; Immunoglobulin E/*blood/immunology ; Korea ; Quality Control

BACKGROUND: The importance and usefulness of therapeutic drug monitoring (TDM) have been emphasized, and analysis of drugs has been increased in clinical laboratories. We evaluated the analytical performance and clinical usefulness of a recently introduced enzyme multiplied immunoassay instrument, Viva-E Drug Testing System (Dade Behring Inc., USA). METHODS: Using patients' samples and quality control material, we evaluated the analytical performance of Viva-E for a total of 11 drugs (cyclosporine, tacrolimus, mycophenolic acid, valproic acid, digoxin, theophylline, carbamazepine, phenytoin, phenobarbital, vancomycin, and gentamicin) with respect to linearity, precision, and correlations with other methods according to CLSI guidelines. Cobas Integra 800 (Roche Diagnostics, Switzerland) and API 4000 LC-MS/MS System (Applied Biosystems, USA) were used to make a comparison. In addition, we analyzed analysis time. RESULTS: Viva-E showed a good linearity (r2 > or = 0.97) for all items. Within-run CVs were within 5% and total CVs were within 10% for all drugs except for tacrolimus and digoxin at low concentrations. The system correlated well with the other methods (r=0.9283-0.9778). The time required for reporting the first sample was 11 min and the analysis time was 1.1 min. CONCLUSIONS: Since Viva-E showed a good analytical performance required for TDM in its linearity, precision, and accuracy with its wide drug menus including cyclosporine, tacrolimus, and mycophenolic acid, stat and random accessing functions, and the consolidation to a single workstation, it could be very useful in the clinical laboratory for various needs.
Data Interpretation, Statistical ; Drug Monitoring/*instrumentation/methods ; Enzyme Multiplied Immunoassay Technique/*instrumentation ; Humans ; Immunoenzyme Techniques ; Pharmaceutical Preparations/*analysis ; Quality Control ; Reference Standards ; Reproducibility of Results