Comparison of Becton Dickinson Vacutainer rapid serum tube with the serum separator tube for routine chemistry and immunoassay tests.

AIMS: To shorten the clotting time and resolve the delayed clotting or no clotting on specimens from patients on anticoagulant therapy, Becton Dickinson (BD) recently developed the Vacutainer rapid serum tube (RST). The aim of this study was to systematically compare the new RST tube with the widely used serum separator tube (SST) for routine chemistry and immunoassay tests on 3 common analyser platforms. METHODS: Blood from 45 people (24 women and 21 men, age 21-77 years) was collected using the SST and RST tubes in sequence. Sera from both tubes were separated and analysed simultaneously for 54, 50, and 10 chemistry and/or immunoassay tests on the Roche Modular, Abbott Architect, and Siemens Centaur analysers, respectively. RESULTS: The results from the RST tube were comparable with those from the SST tube on most analytes. Although the results for a few analytes showed statistically significant differences between the two tubes (p<0.05), the differences had no clinical significance for most assays. Only for parathyroid hormone on the Abbott Architect, the RST tube demonstrated clinical significant bias versus the SST tube (-15.3%, p<0.01). CONCLUSIONS: The RST tube provides acceptable performance for routine chemistry and immunoassay tests.

Performance evaluation of Siemens ADVIA Centaur enhanced estradiol assay and a split sample comparison with liquid chromatography-tandem mass spectrometry.

OBJECTIVES: The objective of this study was to evaluate the newly developed Siemens ADVIA Centaur enhanced Estradiol (eE2) assay and compare it with a well-established estradiol liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. DESIGN AND METHODS: The Siemens eE2 assay was evaluated using the Clinical and Laboratory Standards Institute evaluation protocols. Split patient samples were compared with the eE2 assay, the current ADVIA Centaur E2-6 Ill assay; and LC-MS/MS method by API5000 mass spectrometer. RESULTS: Within-run and total imprecision of the eE2 assay demonstrated coefficient of variations of 5.7%, 3.2%, 1.5%, and 10.4%, 7.3%, and 6.8%, at levels of 380, 752, and 2051 pmol/L, respectively. The method comparisons showed: eE2=0.903(E2-6 III) -16.2, R(2)=0.938, average bias=-12.3%; and eE2=0.946(LC-MS/MS)+19.5, R(2)=0.925, average bias: 0%. CONCLUSION: The Siemens eE2 assay correlates well with LC-MS/MS. This method is reliable, and appropriate for routine clinical laboratory use.

Performance evaluation of Siemens ADVIA Centaur and Roche MODULAR Analytics E170 Total 25-OH Vitamin D assays.

OBJECTIVES: To evaluate the newly developed Roche MODULAR Analytics E170 Total Vitamin D and the Siemens ADVIA Centaur Vitamin D Total assays. MATERIALS AND METHODS: Assays were evaluated using the Clinical and Laboratory Standards Institute protocols. Split patient samples were compared with LC-MS/MS and DiaSorin LIAISON assays (n=79 including 15 specimens with detectable endogenous 25-OH vitamin D(2)). Assay accuracy was also evaluated using the Vitamin D External Quality Assessment Scheme (DEQAS) samples. RESULTS: The ADVIA Centaur and E170 assays demonstrated maximum total CVs of 14.1% and 5.9%, respectively. Both showed excellent linearity (R(2)>0.99). The ADVIA Centaur assay demonstrated interference with bilirubin at 800 µmol/L, hemolysis at 1.25 g/L, and triglycerides at 2.8 mmol/L. Compared to LC-MS/MS, the ADVIA Centaur assay demonstrated a R(2) value of 0.893, average bias of -8.8%; the E170 assay an R(2) value of 0.872, average bias of 14.3% with underestimation of 25-OH vitamin D(2). Compared to the LIAISON assay, the ADVIA Centaur assay demonstrated an R(2) value of 0.781, average bias of -17.3%; the E170 assay an R(2) value of 0.823, average bias of 11.4%. The ADVIA Centaur and E170 assays demonstrated a biases of <20% in 10/10 and 8/10 DEQAS samples, respectively. CONCLUSIONS: The ADVIA Centaur and E170 vitamin D assays demonstrated acceptable linearity, imprecision, and accuracy. The E170 assay demonstrated consistent underestimation of 25-OH vitamin D(2) levels. Compared with LC-MS/MS, the ADVIA Centaur assay demonstrated a higher R(2) value and a smaller average bias than the E170 assay.