Comparison of Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for measurement of cardiac troponin I

Author(s):  
Jau-Tsuen Kao ◽  
I-Li Wong ◽  
Jeen-Yih Lee ◽  
Ruey-Chean Chen

Myocardial infarction is a common cause of morbidity and mortality in patients with chest pain. The presence of human cardiac troponin I (cTnI) in serum is considered to be a highly specific biochemical marker of acute myocardial infarction. In this study we compare the performances of the Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for the measurement of cTnI. The first two methods use a fluorogenic enzyme-linked immunoassay, whereas the last two use chemiluminescent immunometric assays. All procedures are completely automated. Total percentage coefficients of variation using pooled sera ranged from 5·9 to 6·5% for the AxSYM, 14·4 to 25·6% for the Opus, 6·9 to 9·8% for the Immulite and 4·5 to 5·2% for the Vitros ECi method. The closest correlation between methods, obtained from 120 fresh serum samples, was observed between the Vitros ECi and the Immulite methods, with r=0·99, and the regression line was Immulite cTnI=1·505 (95% confidence interval 1·474-1·536) x Vitros cTnI-0·154 (-0·702 to 0·394). Receiver operating characteristic curves were nearly identical for all assays, and the areas under the curves were 0·972, 0·927, 0·967 and 0·969 for the AxSYM, Opus, Immulite and Vitros ECi methods, respectively. There was a significant difference between the AxSYM and Opus methods ( P=0·036).

Author(s):  
Peter A. Kavsak ◽  
Tara Edge ◽  
Chantele Roy ◽  
Paul Malinowski ◽  
Karen Bamford ◽  
...  

AbstractObjectivesTo analytically evaluate Ortho Clinical Diagnostics VITROS high-sensitivity cardiac troponin I (hs-cTnI) assay in specific matrices with comparison to other hs-cTn assays.MethodsThe limit of detection (LoD), imprecision, interference and stability testing for both serum and lithium heparin (Li-Hep) plasma for the VITROS hs-cTnI assay was determined. We performed Passing-Bablok regression analyses between sample types for the VITROS hs-cTnI assay and compared them to the Abbott ARCHITECT, Beckman Access and the Siemens ADVIA Centaur hs-cTnI assays. We also performed Receiver-operating characteristic curve analyses with the area under the curve (AUC) determined in an emergency department (ED)-study population (n=131) for myocardial infarction (MI).ResultsThe VITROS hs-cTnI LoD was 0.73 ng/L (serum) and 1.4 ng/L (Li-Hep). Stability up to five freeze-thaws was observed for the Ortho hs-cTnI assay, with the analyte stability at room temperature in serum superior to Li-Hep with gross hemolysis also affecting Li-Hep plasma hs-cTnI results. Comparison of Li-Hep to serum concentrations (n=202), yielded proportionally lower concentrations in plasma with the VITROS hs-cTnI assay (slope=0.85; 95% confidence interval [CI]:0.83–0.88). In serum, the VITROS hs-cTnI concentrations were proportionally lower compared to other hs-cTnI assays, with similar slopes observed between assays in samples frozen <−70 °C for 17 years (ED-study) or in 2020. In the ED-study, the VITROS hs-cTnI assay had an AUC of 0.974 (95%CI:0.929–0.994) for MI, similar to the AUCs of other hs-cTn assays.ConclusionsLack of standardization of hs-cTnI assays across manufacturers is evident. The VITROS hs-cTnI assay yields lower concentrations compared to other hs-cTnI assays. Important differences exist between Li-Hep plasma and serum, with evidence of stability and excellent clinical performance comparable to other hs-cTn assays.


2018 ◽  
Vol 56 (3) ◽  
pp. 492-501 ◽  
Author(s):  
Silvia Masotti ◽  
Concetta Prontera ◽  
Veronica Musetti ◽  
Simona Storti ◽  
Rudina Ndreu ◽  
...  

AbstractBackground:The study aim was to evaluate and compare the analytical performance of the new chemiluminescent immunoassay for cardiac troponin I (cTnI), called Access hs-TnI using DxI platform, with those of Access AccuTnI+3 method, and high-sensitivity (hs) cTnI method for ARCHITECT platform.Methods:The limits of blank (LoB), detection (LoD) and quantitation (LoQ) at 10% and 20% CV were evaluated according to international standardized protocols. For the evaluation of analytical performance and comparison of cTnI results, both heparinized plasma samples, collected from healthy subjects and patients with cardiac diseases, and quality control samples distributed in external quality assessment programs were used.Results:LoB, LoD and LoQ at 20% and 10% CV values of the Access hs-cTnI method were 0.6, 1.3, 2.1 and 5.3 ng/L, respectively. Access hs-cTnI method showed analytical performance significantly better than that of Access AccuTnI+3 method and similar results to those of hs ARCHITECT cTnI method. Moreover, the cTnI concentrations measured with Access hs-cTnI method showed close linear regressions with both Access AccuTnI+3 and ARCHITECT hs-cTnI methods, although there were systematic differences between these methods. There was no difference between cTnI values measured by Access hs-cTnI in heparinized plasma and serum samples, whereas there was a significant difference between cTnI values, respectively measured in EDTA and heparin plasma samples.Conclusions:Access hs-cTnI has analytical sensitivity parameters significantly improved compared to Access AccuTnI+3 method and is similar to those of the high-sensitivity method using ARCHITECT platform.


2018 ◽  
Vol 64 (7) ◽  
pp. 1104-1112 ◽  
Author(s):  
Ivan A Katrukha ◽  
Alexander E Kogan ◽  
Alexandra V Vylegzhanina ◽  
Alexey V Kharitonov ◽  
Natalia N Tamm ◽  
...  

Abstract BACKGROUND In the blood of patients with acute myocardial infarction (AMI), cardiac troponin I (cTnI) presents as an intact molecule with a repertoire of proteolytic fragments. The degradation of cTnI might negatively influence its precise immunodetection. In this study we identified cTnI fragments and calculated their ratio in the blood of patients at different times after AMI to discriminate the most stable part(s) of cTnI. METHODS Serial serum samples were collected from AMI patients within 1 to 36 h after the onset of chest pain both before and after stenting. cTnI and its fragments were immunoextracted from serum samples and analyzed by Western blotting with monoclonal antibodies (mAbs) specific to the different epitopes of cTnI and by 2 in-house immunoassays specific to the central and terminal portions of cTnI. RESULTS Intact cTnI and its 11 major fragments were detected in blood of AMI patients. The ratio of the fragments in serial samples did not show large changes in the period 1–36 h after AMI. mAbs specific to the epitopes located approximately between amino acid residues (aar) 34 and 126 stained all extracted cTnI. mAbs specific to aar 23–36 and 126–196 recognized approximately 80% to 90% (by abundance) of cTnI. CONCLUSIONS In addition to mAbs specific to the central part of cTnI (approximately aar 34–126), antibodies specific to the adjacent epitopes (approximately aar 23–36 and 126–196) could be used in assays because they recognize ≥80% of cTnI in patients' blood samples within the first 36 h after AMI.


Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6988
Author(s):  
Remya Radha ◽  
Mohammad Hussein Al-Sayah

Cardiovascular diseases (CVDs) are one of the foremost causes of mortality in intensive care units worldwide. The development of a rapid method to quantify cardiac troponin I (cTnI)—the gold-standard biomarker of myocardial infarction (MI) (or “heart attack”)—becomes crucial in the early diagnosis and treatment of myocardial infarction (MI). This study investigates the development of an efficient fluorescent “sandwich” immunoassay using liposome-based fluorescent signal amplification and thereby enables the sensing and quantification of serum-cTnI at a concentration relevant to clinical settings. The calcein-loaded liposomes were utilized as fluorescent nano vehicles, and these have exhibited appropriate stability and efficient fluorescent properties. The standardized assay was sensitive and selective towards cTnI in both physiological buffer solutions and spiked human serum samples. The novel assay presented noble analytical results with sound dynamic linearity over a wide concentration range of 0 to 320 ng/mL and a detection limit of 6.5 ng/mL for cTnI in the spiked human serum.


2000 ◽  
Vol 46 (4) ◽  
pp. 453-460 ◽  
Author(s):  
David A Morrow ◽  
Nader Rifai ◽  
Milenko J Tanasijevic ◽  
Donald R Wybenga ◽  
James A de Lemos ◽  
...  

Abstract Background: Significant analytic variability exists between the multiple assays for cardiac troponin I (cTnI) approved for clinical use. Until adequate cTnI standardization is possible, an evidence-based approach evaluating each assay at specific thresholds appears warranted. Methods: We examined the efficacy of three cTnI assays for predicting death, myocardial infarction (MI), or the composite of death, MI, or urgent revascularization at 43 days among patients with non-ST-elevation acute coronary syndromes enrolled in the Thrombolysis In Myocardial Infarction (TIMI) 11B study. Results: Six hundred eighty-one patients with serum samples obtained at baseline and/or 12–24 h had cTnI determined using all three assays. Baseline cTnI was ≥0.1 μg/L for 368, 395, and 418 patients with the Bayer Immuno 1TM, ACS:180®, and Dimension® RxL assays, respectively. Correlation coefficients for the RxL with the ACS:180 and Bayer Immuno 1 results were 0.89 (P = 0.0001) and 0.87 (P = 0.0001), with a coefficient of 0.92 (P = 0.0001) for the ACS:180 and Bayer Immuno 1 assays. Patients with cTnI ≥0.1 μg/L were at increased risk for death or MI by 43 days (relative risk, 2.2–3.0; P &lt;0.0006), regardless of the assay used. This prognostic capacity persisted among those with creatine kinase MB isoenzyme concentrations within the reference interval. Moreover, cTnI was the strongest multivariate predictor of death, MI, or urgent revascularization with adjusted odds ratios of 2.1–2.9 (P &lt;0.0006). Conclusion: This study demonstrates the prognostic efficacy of three independently developed cTnI assays at a threshold of 0.1 μg/L for the prediction of adverse clinical outcomes among patients with non-ST-elevation acute coronary syndromes.


2013 ◽  
Vol 61 (4) ◽  
pp. 442-453 ◽  
Author(s):  
Mohamed Tharwat ◽  
Fahd Al-Sobayil ◽  
Mehana El-Sayed

This study was designed to establish serum cardiac troponin I (cTnI) concentrations in healthy newborn goat kids and in those with cardiac nutritional muscular dystrophy (NMD). Thirty-five single full-term newborn goat kids (20 males and 15 females; age: 6.1 ± 3.5 h; weight 3.4 ± 0.68 kg), together with their respective mothers (Group 1; G1) were enrolled consecutively. Thirty-one goat kids (age: 9.5 ± 4.3 days) with NMD, together with 20 control goat kids (age: 7.8 ± 4.3 days) were also included in this study (Group 2; G2). Blood samples were collected from G1 within 12 h of birth and from G2 on admission. Serum samples were collected and analysed for cTnI. In G1, the mean serum concentration of cTnI in goat kids was 0.290 ± 0.37 ng/mL, with no statistically significant difference between male and female kids (P = 0.61). The mean cTnI concentration in the does was 0.017 ± 0.04, ng/mL. Serum values of cTnI in the goat kids and in their respective mothers differed significantly (P = 0.0001). In G2, the mean cTnI concentration was 0.02 ± 0.05 ng/mL in the control and 11.18 ± 20.07 ng/mL in the diseased goat kids, with a statistically significant difference between diseased and control goat kids (P = 0.017). Serum concentrations of cTnI are higher in goat kids than in their respective mothers. In conclusion, the cTnI assay appears to be a sensitive and specific marker for myocardial injury in goat kids.


Diagnostics ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 614
Author(s):  
Diana Hernández-Romero ◽  
María del Rocío Valverde-Vázquez ◽  
Juan Pedro Hernández del Rincón ◽  
José A. Noguera-Velasco ◽  
María D. Pérez-Cárceles ◽  
...  

In approximately 5% of unexpected deaths, establishing a conclusive diagnosis exclusively on the basis of anatomo-pathological findings in a classic autopsy is difficult. Postmortem biomarkers have been actively investigated as complementary indicators to help to reach valid conclusions about the circumstances of death. Several studies propose either the pericardial fluid or peripheral veins as a location for troponin determination, but the optimum sampling site is still a matter of debate. Our objective was to evaluate the association between the ratio of troponin values in the pericardial fluid and serum (determined postmortem) and the diagnosis of acute myocardial infarction (AMI) in the context of sudden cardiac death. We included 175 forensic cases. Two groups were established: AMI deaths (48; 27.4%) and the control group (127; 72.6%). The cardiac Troponin I (cTnI) values in the pericardial fluid and the troponin ratio were found to be associated with the cause of death. Univariate regression analyses showed that both age and the cTnI ratio were significantly associated with the diagnosis of AMI death. In a multivariate analysis, adjusting for confounding factors, the age and cTnI ratio were independent predictors of death from myocardial infarction. We performed a receiver operating characteristic (ROC) curve for the cTnI ratio for AMI death and selected a cut-off point. Our biomarker was found to be a valuable and highly effective tool for use in the forensic field as a complementary method to facilitate diagnosis in nonconclusive autopsies.


Sign in / Sign up

Export Citation Format

Share Document