Olympus AU Research Articles

Comparison of Two Different Methods for Cardiovascular Risk Assessment: Framingham Risk Score and Score System

Comparison of Two Different Methods for Cardiovascular Risk Assessment:Framingham Risk ScoreandScoreSystemNumerous studies have shown that the major risk factors for coronary heart disease (cigarette smoking, hypertension, elevated serum total cholesterol and low-density lipoprotein cholesterol - LDL, low serum high-density lipoprotein cholesterol - HDL, diabetes mellitus and advancing age), are additive in predictive power. Accordingly, the total risk of a person can be estimated by summing up the risk imparted by each of the major risk factors. Using data obtained from population studies, various risk assessment algorithms have been developed. The aim of this study was to compare the two most common risk scores. Risk assessment for determining 10-year risk in 185 healthy, asymptomatic individuals of both sexes, 30-85 years old, was carried out according to both Framingham (FRS) and SCORE risk scoring. The risk factors included in the calculation of 10-year risk are gender, age, total cholesterol, HDL-cholesterol, systolic blood pressure, treatment for hypertension and cigarette smoking. The determinations of total cholesterol and HDL-cholesterol were made in sera collected after a 12h fasting period using an Olympus AU2700 automated analyzer. The Framingham risk score was determined using an electronic calculator - ATP III Risk Estimator, and the risk status according to SCORE was obtained using charts for the 10-year risk in populations at high risk. Among 185 participants, in 152 (82%) 10-year risk for Coronary Heart Disease (CHD) death was <10%, 24 (13%) had intermediate and 9 (5%) had high risk (⩾20%) according to FRS. According to SCORE, 110 (60%) participants had <1%, 56 (30%) had 1-5% and 19 (10%) had ⩾5% of 10-year risk for cardiovascular death. Different categories of risk were assigned to ~30% of individuals according to different risk assessment models. Differences in risk classification when using two different risk assessment algorithms can be explained with several important issues, including different endpoints, consideration of interactions and incorporation of antihypertensive use. It is important to note that neither FRS nor SCORE have been appropriately adjusted for our population, according to the national cardiovascular mortality rate.

High postprandial triglyceridemia in patients with type 2 diabetes and microalbuminuria

Microalbuminuria (MA) is an independent risk factor for atherosclerosis in patients with type 2 diabetes mellitus (T2DM). Postprandial lipemia is also associated with excess cardiovascular risk. However, the association between MA and postprandial lipemia in diabetes has not been investigated. A total of 64 patients with T2DM, 30 with and 34 without MA, were examined. Plasma total triglycerides (TGs), triglycerides contained in chylomicrons (CM-TG), and TGs in CM-deficient plasma were measured at baseline and every 2 h for 6 h after a mixed meal. Postheparin LPL and HL activities were also determined. Plasma levels of apolipoprotein A-V (apoA-V), apoC-II, and apoC-III were measured in the fasting state and 2 h postprandially. Patients with MA had higher postprandial total TG levels than those without MA (P < 0.001); this increase been attributed mainly to CM-TG. LPL activity and fasting concentrations of the measured apolipoproteins were not different between the studied groups, whereas HL activity was higher in the patients with MA. ApoC-II and apoC-III levels did not change postprandially in either study group, whereas apoA-V increased more in the patients with MA. These data demonstrate for the first time that MA is characterized by increased postprandial lipemia in patients with T2DM and may explain in part the excess cardiovascular risk in these patients.

MONITORING OF ADIPOCYTE RESPONSIVENESS BY IN SITU MICRODIALYSIS IN LIPODYSTROPHY TISSUE: ADJUSTMENT OF A GLYCEROL QUANTIFICATION METHOD IN SMALL SAMPLES

In situ microdialysis allows monitoring of metabolic cellular processes at the tissue level in vivo. In the assessment of physiopathologic alterations seen in lipodystrophy, monitoring of glycerol release is pivotal. Indeed, it allows to quantify the pharmacological responsiveness of subcutaneous adipose tissue in humans. Until now, the small volume of microdialysate collected (5-15µL/sample) restricted the assessment of glycerol level to the use of the radio-enzymatic method or the reference spectrophotometric microanalysis technique. The aim of this study was to adapt the method of glycerol measurement by iminequinone spectrophotometry colorimetric assay (520 nm) using the following reagent : 0.5 IU Glycerokinase, 1.23 IU glycerophosphate oxidase, 0.98 IU peroxidase, 4.6 mM Mg, 5.4 mM 4-chlorophenol, 0.25 mM 4-aminoantipyrine and 1.4 mM ATP. The assay was setup to run on Olympus AU 2700 automate (15 µL sample volume). The sensitivity of the method was improved by adding a 0.2 mmol triglyceride (TG) solution and 1.5 IU lipase to samples, reducing the limit of free glycerol quantification to 0.020 mmol/L. The analytical repeatability was 2.0% and the reproducibility was 7.9%.The present method thus demonstrated the feasibility of pharmacodynamic exploration of local cutaneous responsiveness in vivo in clinical trials.

Transcriptome analysis of a rat PKD model: Importance of genes involved in extracellular matrix metabolism

Transcriptome analysis of a rat polycystic kidney disease (PKD) model: importance of genes involved in extracellular matrix metabolism. PKD is a common genetic cause of chronic renal failure, and is characterized by the accumulation of fluid-filled cysts in the kidneys and other organs. Abnormalities in the expression of selected genes thought to be involved in cystogenesis have been described, but no systematic analysis of the global transcriptomal pattern has been reported. With this aim, a rat oligomicroarray was used to identify variations in gene expression in Han:Sprague-Dawley Cy/Cy rats, an animal model presenting a severe PKD phenotype. Some upregulated genes were validated using real-time polymerase chain reaction in Cy/Cy and Cy/+ rats. Among the 350 genes identified as being upregulated, we found about 30 genes involved in extracellular matrix metabolism. These genes encoded proteins or peptides that could be implicated into two different biological processes: molecules involved in fibrosis and proteins involved in adhesion to the extracellular matrix. In heterozygotes, some genes (glypican 3, fibronectin 1) were already upregulated in early stages of the disease. We conclude that differential regulation of genes linked to extracellular matrix metabolism may be one of the first events leading to tubule enlargement and subsequent cyst formation in PKD.

Comparison of five tuna plasma analytes measured on two automated blood analyzers

Plasma biochemistry parameters of 32 bluefin tuna were analyzed on two blood analyzer systems, VetTest 8008 and Olympus AU2700, and the results compared and correlated. Statistically significant differences (p<0.0001) between the two analyzers were found for the total cholesterol, triglyceride, and aspartate aminotransferase analytes, but not for those of glucose and total proteins, which demonstrated almost identical values and ranges on both analyzers (p = 0.383 and 0.188, respectively). The coefficients of variation were high for most parameters on both analyzers. Overall, we conclude that data obtained with both analyzers have the same clinical significance. In routine investigations on tuna blood, due to the relatively small numbers of available samples and small sample volumes, it is more likely that the bench-top dry-slide analyzer (VetTest 8008) will be the preferred analytical system to a high-volume primary analyzer (Olympus AU2700).

Measurement of carnitine in hemodialysis patients – adaptation of an enzymatic photometric method for an automatic analyzer

The main goal of this work was to describe the analytical characteristics of an enzymatic photometric test for carnitine determination and its automation using an Olympus analyzer. We used a test from Roche intended for manual processing and tried to apply it for use on an Olympus AU 400 analyzer. The analytical parameters of our modified technique were determined using external quality controls and kit controls, and by measurements in venous blood samples from 85 chronically hemodialyzed patients (before and after hemodialysis) and from 68 healthy blood donors serving as controls. A reference value for free carnitine was estimated parametrically as 40.1+/-17.8 micromol/L. The mean bias for eight control measurements was 5.1%. Sensitivity was calculated as the limit of quantification at 2.6 micromol/L. The intra-assay coefficient of variation was 2.4%. The inter-assay coefficient of variation was 8.3%. Analytical recovery was 101.8%, 99.5% and 95.4%. The main advantages of our automated method in comparison to the original manual method are the smaller amounts of samples, reagents and diluents required and the shorter analysis time. As hemodialysis patients often suffer from carnitine deficiency, we conclude that its determination may be helpful for diagnostic verification.

Comparability of point-of-care whole-blood electrolyte and substrate testing using a Stat Profile Critical Care Xpress analyzer and standard laboratory methods

Rapid technological progress in point-of-care testing allows the measurement of multiple analytes in whole-blood samples. The present study evaluated biosensor-based methods for the measurement of electrolytes and substrates in whole blood using a Stat Profile Critical Care Xpress (Nova Biomedical, Waltham, MA, USA) multiprofile analyzer and their comparability with standard laboratory methods. Because of the increased utilization of arterial blood samples in hospitalized patients and limited information on differences between arterial and venous blood for most routine laboratory tests, analytical differences caused by different sample types were evaluated. Whole-blood arterial samples and venous serum samples were obtained from 70 random patients with a variety of diagnoses admitted to the intensive care unit. The Stat Profile Critical Care Xpress analyzer was used to obtain whole-blood electrolyte and substrate profiles. For comparison studies, plasma or serum samples were analyzed according to standard laboratory methods using an Olympus AU 600 analyzer (Olympus Mishima, Shizuoka, Japan). Imprecision, expressed as the coefficient of variation (CV%), was less than 5.7% for all analytes at both high and low concentrations, except for creatinine, with a CV of 13.8% for low and 9.5% for high concentrations. The inaccuracy of electrolyte and substrate measurements in whole blood using a Stat Profile Critical Care Xpress analyzer met the analytical quality specification required for near patient testing, with observed bias within the range -4.5% to 5.3%. Statistically significant correlation (p<0.05) was obtained between standard laboratory methods performed on arterial plasma or venous serum samples on an Olympus AU 600 analyzer and direct whole-blood measurements on the Stat Profile Critical Care Xpress point-of-care analyzer for all parameters tested, although slope and intercept values showed analytical differences for electrolyte measurement. The Stat Profile Critical Care Xpress multiprofile point-of-care analyzer provides rapid and accurate direct whole-blood measurement with acceptable performance compared to standard laboratory methods. The results obtained for electrolytes and substrates in whole blood were comparable to those for standard laboratory methods using arterial plasma or venous serum samples.

Synthetic LXR agonists increase LDL in CETP species

Liver X receptor (LXR) nuclear receptors regulate the expression of genes involved in whole body cholesterol trafficking, including absorption, excretion, catabolism, and cellular efflux, and possess both anti-inflammatory and antidiabetic actions. Accordingly, LXR is considered an appealing drug target for multiple indications. Synthetic LXR agonists demonstrated inhibition of atherosclerosis progression in murine genetic models; however, these and other studies indicated that their major undesired side effect is an increase of plasma and hepatic triglycerides. A significant impediment to extrapolating results with LXR agonists from mouse to humans is the absence in mice of cholesteryl ester transfer protein, a known LXR target gene, and the upregulation in mice but not humans of cholesterol 7alpha-hydroxylase. To better predict the human response to LXR agonism, two synthetic LXR agonists were examined in hamsters and cynomolgus monkeys. In contrast to previously published results in mice, neither LXR agonist increased HDL-cholesterol in hamsters, and similar results were obtained in cynomolgus monkeys. Importantly, in both species, LXR agonists increased LDL-cholesterol, an unfavorable effect not apparent from earlier murine studies. These results reveal additional problems associated with current synthetic LXR agonists and emphasize the importance of profiling compounds in preclinical species with a more human-like LXR response and lipoprotein metabolism.

Paraprotein Interference in an Assay of Conjugated Bilirubin

Artifactually increased total bilirubin and artifactually low HDL have been described recently in a patient with a monoclonal IgM paraprotein (1). Similar interferences have already been described for serum samples containing paraproteins when tested for bilirubin [with a reagent from the same manufacturer (2)], phosphate(3)(4)(5)(6)(7), creatinine (8), calcium(9), urea nitrogen(10), iron (11), C-reactive protein, and antistreptolysin-O (12). Here we describe interference in the measurement of conjugated bilirubin by a different analyzer in sera from 3 patients (A, B, and C) with IgG-κ–type myeloma. Conjugated bilirubin was initially measured with the Olympus AU2700 automated analyzer using the Olympus conjugated bilirubin assay. For patient A (40-year-old man), the reported conjugated bilirubin was 37.5 mg/L, total bilirubin was 2.0 mg/L (reference interval, 0.0–11.0 mg/L), and total protein was 156 g/L with …

Reference interval for calculated total iron-binding capacity using Olympus AU2700 analyzer

Total iron-binding capacity (TIBC) values are determined on Olympus AU2700 automated chemistry analyzer as the sum of serum iron and unsaturated iron-binding capacity (UIBC) - (calculated TIBC, TIBCcal). Considering that Olympus AU2700 automated analyzer was recently brought in function and TIBC values calculated from serum iron and UIBC values were significantly lower than those obtained by a direct and fully automated TIBC assay, it was necessary to determine the reference interval for TIBC, according to the recommendation that every laboratory should have its own reference ranges. The "calculation method" of TIBC determination showed satisfactory accuracy (p &gt; 0.001) and precision, with CV values ranging from 0.91% to 1.63% within-run and from 2.30% to 2.80% day-to-day. The correlation between the TIBC values obtained with the "calculation method" using Olympus AU2700 analyzer (y) and those obtained with the direct method (x) was: y = 0.919x + 2.319 mmol/L (r = 0.980; Sy,x = 1.814; p &lt; 0.001; N = 85). The reference interval for TIBC was determined using sera collected from 125 healthy individuals of both sexes, 15 to 80 years old. Since the values did not depend on sex, the reference interval calculated for the whole studied population ranged between 42.0 mmol/L and 64.3 mmol/L.

Evaluation of the ABX Pentra 400: a newly available clinical chemistry analyser

The performance of the ABX Pentra 400, a new multiparametric analyser available for routine and specialised clinical chemistry analyses, was evaluated according to the National Committee for Clinical Laboratory Standards (NCCLS) and Valtec protocols. Substrate concentrations and enzyme activities were determined by spectrophotometric measurement after coloured reaction or UV detection-based reactions; electrolyte concentrations were determined with ion-selective electrodes, and specific protein concentrations were assayed by immunoturbidimetry. In total, 32 of the most common clinical chemistry parameters were evaluated under simulated routine conditions. The analytical performance of the system and the quality of the ABX Pentra reagent line were both examined in a single-site study. The ABX Pentra 400 was compared with the Olympus AU640, Konelab-Konepro, Beckman Coulter-Immage and Beckman Coulter-Access 2, depending on the tests available on these analysers. The coefficient of variation (CV) values were within expected values. Coefficients of correlation showed high correlation between the analysers compared. The influence of interfering substances was moderate. The practicability of the system was good. We conclude that good reliability and practicability make the ABX Pentra 400 system suitable for laboratories with various needs.

Evaluation of the Konelab 20XT clinical chemistry analyzer

The Konelab 20XT (Thermo Electron Oy, Finland) is a clinical chemistry analyzer for colorimetric, immunoturbidimetric and ion-selective electrode measurements. The aim of our work was to evaluate the analytical performances of the Konelab 20XT according to the European Clinical Chemistry Laboratory Standards Guidelines. A total of 30 analytes including substrates, enzymes, electrolytes and specific proteins were tested. Investigation results showed low imprecision (within-run coefficient of variation was below 3.5% and between-day coefficient of variation was less than 2.5% for most analytes at all three levels studied) and acceptable accuracy of the analyzer. No significant sample- or reagent-related carry-over was found. It was demonstrated that the analytical system operates within the claimed linearity ranges. The results compared well with those obtained by instruments routinely used in our laboratory (Olympus AU2700, Behring Nephelometer II). In general, the data on interference by hemoglobin, hyperbilirubinemia and turbidity are in accordance with known facts. However, slight hemolysis was found to interfere with the alkaline phosphatase (ALP) assay and mild lipemia affected the glucose assay. The Konelab 20XT is an easy-to-use analyzer that is suitable for routine and emergency analyses in small laboratories.

Preliminary evaluation of the performance of a new, highly sensitive commercial immunoassay for serum ferritin determination

We evaluated the analytical performance of a new, commercial, fully automated immunoturbidimetric assay for the determination of ferritin [FER-Latex(X2)CN SEIKEN, Denka Seiken, Japan] in serum on the Olympus AU2700 analyzer. The new assay is a latex-enhanced turbidimetric immunoassay with an analysis time of 10 min. The linearity of the assay was confirmed up to 2505 pmol/L (R2=0.999). The detection limit and the functional sensitivity were both 4.5 pmol/L. The intra- and inter-assay imprecision (CV) at 67, 506, 2186 pmol/L was < 1.8% and < 2.5%, respectively. Verification of the traceability to a WHO standard (80/578) showed a recovery of 102.6% (target value 449 pmol/L). No hook effect was observed in samples containing up to 33,705 pmol/L. The assay showed good correlation with the Beckman Immage nephelometric system (r=0.999). Hemoglobin (< or = 9.8 g/L), total bilirubin (< or = 113 micromol/L), conjugated bilirubin (< or = 109 micromol/L) and rheumatoid factor (< or = 5.2x10(5) IU/L) did not interfere with the assay. The reference interval (2.5-97.5 percentile) was 72-521 pmol/L for men and 27-267 pmol/L for women. The reference interval in patients with anemia, malignant tumors and hemochromatosis was 5.6-52, 130-2436 and 1465-2903 pmol/L, respectively. On the basis of the receiver operating characteristic curve, the 90% sensitivity cut-off value to distinguish between patients with and without iron deficiency was 40 pmol/L. The new latex turbidimetric procedure for ferritin assay is an attractive alternative that avoids the need for dedicated instrumentation.

Serum Free Light Chain Levels in Asymptomatic Myeloma.

Introduction: Patients with asymptomatic myeloma fulfil two of the diagnostic criteria for myeloma having more than 10% bone marrow plasma cells and an M protein of greater than 30g/l, but they are asymptomatic with no evidence of end organ or tissue damage. The median time to disease progression is 12–32 months. These patients do not require treatment but do require monitoring for progression to symptomatic myeloma. Predicting progression of asymptomatic myeloma would be of clinical benefit to optimise monitoring and initiate treatment prior to substantial end organ damage. However monoclonal spike, plasma cell labelling index, bone marrow plasmacytosis, immunoparesis and the presence of Bence Jones protein have limited value in predicting progression. Abnormal levels of serum free light chains are present in 95% of all multiple myeloma patients and have clinical benefit in diagnosis and monitoring of disease. In monoclonal gammopathy of undetermined significance (MGUS) 60% of patients have abnormal serum free light chain ratios and are an independent risk factor for progression to myeloma. The aim of this study was to examine the serum of asymptomatic patients for serum free light chains at diagnosis and to determine if they are predictive of disease progression.Methods: Archived presentation sera were studied from forty three asymptomatic myeloma patients who had been registered into United Kingdom Medical Research Council trials (1980 – 2002). Archived presentation sera were assayed for serum free light chains using the serum free light chain assay on an Olympus AU400 analyzer. Times to progression for those with abnormal versus normal serum free light chain ratios were compared. Times to progression were examined by Kaplan-Meier survival curves and log-rank sum statistical analysis.Results: Abnormal serum free light ratios were present in 36/43 (84%) of asymptomatic myeloma patients at the time of diagnosis and the remaining 7 patients had normal ratios. The median follow-up time for all 43 patients was 2807 days. Six patients with a normal kappa/lambda ratio had a median time to progression of 1323 days. In contrast, 26 patients with abnormal serum free kappa/lambda ratios had a median time to progression of 713 days. Ten patients who had an abnormal kappa/lambda ratio had not progressed at the time of follow-up. Although the median time to progression of patients with normal serum free light chain ratios was greater than those with abnormal ratios, this did not reach statistical significance (p<0.13).Conclusions: In summary, 84% of asymptomatic myeloma patients have an abnormal kappa/lambda ratio at diagnosis, in comparison with 95% of multiple myeloma and 60 % of (MGUS) patients. Furthermore, our data suggest that those with normal serum free light chain ratio may progress more slowly than those with abnormal ratios. Due to the small number of patients in this study, this did not reach statistical significance. In the spectrum of malignancy from MGUS to asymptomatic and symptomatic myeloma serum free light chain levels have an increasing frequency of abnormality and are associated with increased risk of progression to symptomatic myeloma.

Plasma glucose measurement with the Yellow Springs Glucose 2300 STAT and the Olympus AU640

Background: Diabetes mellitus is an important diagnosis. New criteria have been defined for impaired glucose metabolism and, accordingly, there is a need for precise and accurate glucose analysis for the...

Direct Serum Total Iron-binding Capacity Assay Suitable for Automated Analyzers

Present methods for measuring serum total iron-binding capacity (TIBC) involve manipulation of samples or performance of two assays on each sample. We developed a direct automated assay (DTIBC) for TIBC. We added to serum a saturating amount of iron bound to an excess of chelating dye at a low pH, recorded a blank reading that represented the sum of the saturating amount of iron plus the serum iron, and then added a strong neutral pH buffer. The decrease in absorbance (as transferrin extracts iron from the iron-dye complex) is directly proportional to the TIBC. TIBC values for 125 patients were determined by DTIBC, alumina column TIBC (AC), magnetic particle TIBC (MTIBC), and the UIBC method (UIBC) on Roche COBAS FARA and Mira chemistry analyzers. In a separate study, TIBC values for 128 patients were determined on an Olympus AU400 by the DTIBC and the MTIBC methods. Methods comparisons on the COBAS analyzers yielded the following results: DTIBC = 1.05(MTIBC) - 1.0 micromol/L (r = 0.987; S(y/x) = 2.6 micromol/L); DTIBC = 1.07(AC) - 1.0 micromol/L (r = 0.982; S(y/x) = 3.0 micromol/L); and DTIBC = 1.14(UIBC) + 3.4 micromol/L (r = 0.982; S(y/x) = 3.0 micromol/L). A similar correlation study using the Olympus AU400 yielded DTIBC = 1.00(MTIBC) - 0.1 micromol/L (r = 0.983; S(y/x) = 2.7 micromol/L). The assay was linear from 12.5 to 125 micromol/L (70-700 microg/dL) TIBC on the COBAS FARA. Within- and between-run imprecision (CV) was <or=4.8% at two concentrations. Plasma samples were unsuitable for the method. No interference was seen with common interferants other than ascorbate, deferoxamine, and ferrous sulfate, and only at concentrations well above normal. The new DTIBC assay is suitable for routine use in clinical laboratories and may improve the quality of iron metabolism studies.

Correlation of the Abbott Spectrum with the Olympus AU 5000 for Automated Urine Chemistry Analysis

Correlation of the Abbott Spectrum with the Olympus AU 5000 for Automated Urine Chemistry Analysis

Effekt von Vorspendenergebnissen und vertraulichem Selbstausschluß auf Prävalenz und Inzidenz von HCV bei Blutspendern des DRK-Blutspendedienstes Nordrhein-Westfalen

Objectives: To estimate the remaining risk of HCV transmission from recently infected blood donors and to determine the association of elevated ALT levels and confidential self-exclusion with the marker anti-HCV. Blood Donors and Methods: Between June 22, 1994, and November 11, 1995, 130,476 blood donors donated 294,927 units of whole blood in the Institute Breitscheid of the German Red Cross Blood Transfusion Service of North Rhine-Westphalia; 23,281 were first-time donors. ALT testing was done with an Olympus AU 560 analyzer at 37 °C. Results were corrected with a lot-specific factor to obtain international units that would be measured at 25 °C. Results: 0.32% of first-time donors were repeatably reactive (rr) in the Ortho III anti-HCV enzyme immunoassay (EIA), however only 0.10% were also positive in the RIBA-2. Surprisingly, as many as 0.11% of repeat donors were also EIA-rr and 0.02 (n = 24) were RIBA-positive, but in only two a seroconversion could be demonstrated. EIA-rr results could frequently be confirmed by RIBA when the serum ALT was elevated. If the level of ALT was normal, confirmation was rare. Among the 585 donors who had chosen confidential self-exclusion, neither in the index donation nor in a subsequent donation (n = 374) specific markers for HCV or HIV were found. No seroconversion for HBsAg was observed. Donors who had chosen confidential self exclusion were much more likely to choose confidential self-exclusion on subsequent donations as well. Conclusions:The remaining risk of HCV infection from a recently infected donor is, in our donor population, less than 1 in 100,000 donations. It is likely to be further reduced by ALT testing. A benefit of confidential self-exclusion could not be demonstrated.

Analytical performance of the selective multianalyser Olympus AU 5200

The analytical performance of a selective, automatic multianalyser- the Olympus A U5200 - was tested and assessed for practicability, following ECCLSguidelines. Twenty-two analytes were tested and compared with the Olympus A U5000 analyser. A Hitachi 747 analyser was also included in this survey in order to obtain correlation data for ISE measurements. The imprecision data, expressed as median CV values, were found to be below 2% in series for 21 parameters, and below 3% for 19 paramaters from day to day. Creatinine measured with the kinetic Jaffe method obtained a median CV value of 4% in series, creatine phosphokinase showed the worst imprecision from day to day with a CV of 9%. Slightly better precision values for the majority ofall tests were found on the Olympus AU5200 than on the AU 5000 analyser. The recovery of the assigned values in 32 commercial control sera was between 95% and 105% for 14 tests. Five of the remaining tests yielded recoveries with deviations between 5% and 10%, deviations above 10% showed albumine, alanine aminotransferase, aspartate aminotransferase and creatine phosphokinase. The accuracy of most test parameters was slightly better on the AU5200 analyser than on the comparison instrument. The range of linearity ofthe tested methods covered the range stated by the manufacturers; and no sample carry-over was detected. Most parameters tested yielded close correlation to those on the comparison instrument. Amylase measurements on both analysers correlate well but are not comparable without data correction due to different test methods. In addition, no drift effects were observed over a period of 9 hours. The ion-selective-electrode unit performed well in terms of throughput, precision and stability over time. The whole system showed good practicability with respect to patient sample and reagent handling, a short training period of technicians, ease of system software, maintenence, a robust barcode reader and a flexible host communication procedure.

Analytical performance of the selective, automatic multianalyser Olympus AU 5031

The analytical performance of the selective, automatic multianalyser Olympus AU 5031 was evaluated over four months and assessed for practicability for another eight months. The evaluation followed the ECCLS guidelines. Twenty routine parameters were measured. In addition, sodium and potassium were determined on an attached flame photometric unit. Both the agreement between the eights photometers per unit and the temperature behaviour in the cuvettes was satisfactory. The imprecisions were very good. The within-run imprecision was below 1.5% for the majority of the parameters. The imprecision between days was below 5%, with the exception of creatine phosphokinase (7.4%). Glutamate dehydrogenase gave an imprecision of between 4.0% and 15.9%, which, however, is more likely due to the low activities measured rather than the fault of analyser. The recovery of the assigned values in 12 control sera was between 95% and 105% for 14 tests. Three of the remaining eight tests yielded recoveries with deviations between 10% and 18% (alanine aminotransferase, aspartate aminotransferase and bilirubin). No drift effects were observed and neither a sample carry-over nor a reagent carry-over were detected. Most tests were linear over a very wide range. Only afew tests (mainly lipase and glutamate dehydrogenase) required measurement repetitions with diluted samples. The correlation with routine instruments and tests was close. However, corrections were necessary for 14 of the 22 tests. This was not due to the performance of the analyser but, rather, to the different methodologies of compared tests, or different working temperatures on the comparison instruments, or a lack of accuracy for some of the AU tests.