Analytical comparison between two automated biochemical analyzer systems: Roche Cobas 8000 and Mindray BS2000M

Summary Background. The values of biomarkers play a central role in routine clinical decision-making. Whereas, the performances of different automated chemical analyzers remain unclear. To determine the performances of different platforms, we evaluated the capability between Roche Cobas 8000 and Mindray BS2000M. Methods. A total of 1869 remaining serum samples were collected. CK, LDH-1, RBP, Cys-c, IgA, IgM and IgG were assessed by using paired-t test, Passing-Bablok regression analysis and Bland Altman analysis according to CLSI EP5-A3. Results. There were significant in average bias of all items between two machines (P < 0.001). Due to the 95% confidence interval of intercept A included 0, CK, LDH-1, Cys-c and IgG were not show systemic error in Passing-Bablok regression analysis. Except for IgA, the r values and correlation coefficient of all items were higher than 0.91, which showed that the correlation and consistency is good. The Bland-Altman analysis showed that two instruments had more than 95% of the points apart from CK, LDH-1, and IgA. Conclusions. It can be considered that the two instruments have good correlation and consistency in CK, LDH-1, RBP, Cys-c, IgM and IgG, and the two instruments are interchangeable and can replace each other.

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A Comparison of Peritoneal Equilibration Tests Performed 1 and 4 Weeks after PD Commencement

Peritoneal Dialysis International ◽

10.1177/089686080402400511 ◽

2004 ◽

Vol 24 (5) ◽

pp. 460-465 ◽

Cited By ~ 26

Author(s):

David W. Johnson ◽

David W. Mudge ◽

Sophie Blizzard ◽

Mary Arndt ◽

Amanda O'Shea ◽

...

Keyword(s):

Prospective Observational Study ◽

Clinical Decision Making ◽

Tertiary Care ◽

Clinical Decision ◽

Glucose Measurement ◽

Altman Analysis ◽

Princess Alexandra Hospital ◽

Peritoneal Equilibration Test ◽

Bland Altman Analysis ◽

Peritoneal Transport

Objective The aim of this study was to prospectively evaluate the ability of a peritoneal equilibration test (PET) performed in the first week of peritoneal dialysis (PD) to predict subsequent transport status, as determined by a PET at 4 weeks and >1 year after PD commencement. Design Prospective observational study of an incident PD cohort at a single center. Setting Tertiary-care institutional dialysis center. Participants The study included 50 consecutive patients commencing PD at the Princess Alexandra Hospital between 25/2/2001 and 14/5/2003 (mean age 60.9 ± 12.2 years, 54% male, 92% Caucasian, 38% diabetic). All patients were initially prescribed continuous ambulatory PD. Main Measurements Measurements performed during paired PETs included dialysate-to-plasma ratios of urea (D/P urea) and creatinine (D/P creatinine) at 4 hours, the ratio of dialysate glucose concentrations at 0 and 4 hours (D/D0 glucose), and drain volumes at 4 hours. Results When paired 1-week and 1-month PET data were analyzed, significant changes were observed in measured D/P urea (0.91 ± 0.07 vs 0.94 ± 0.07 respectively; p < 0.05), D/P creatinine (0.55 ± 0.12 vs 0.66 ± 0.11, p < 0.001), and D/D0 glucose (0.38 ± 0.08 vs 0.36 ± 0.10, p < 0.05). Using Bland–Altman analysis, the repeatability coefficients were 0.17, 0.20, and 0.13, respectively. Agreement between 1-week and 1-month PET measurements with respect to peritoneal transport category was moderate for D/D0 glucose (weighted κ 0.52), but poor for D/P urea (0.30), D/P creatinine (0.35), and drain volumes (0.20). The PET measurements performed more than 1 year following PD commencement ( n = 28) generally agreed closely with 1-month measurements, and poorly with 1-week measurements. Conclusions Peritoneal transport characteristics change significantly within the first month of PD. PETs carried out during this time should be considered preliminary and should be confirmed by a PET 4 weeks later. Nevertheless, performing an early D/D0 glucose measurement at 1 week predicted ultimate transport status sufficiently well to facilitate early clinical decision-making about optimal PD modality while patients were still receiving PD training. On the other hand, the widespread practice of using measured drain volumes in the first week to predict ultimate transport category is highly inaccurate and not recommended.

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Pediatric reference interval verification for endocrine and fertility hormone assays on the Abbott Alinity system

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2021-0337 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Mary Kathryn Bohn ◽

Siobhan Wilson ◽

Alexandra Hall ◽

Khosrow Adeli

Keyword(s):

Clinical Decision Making ◽

De Novo ◽

Reference Interval ◽

Clinical Decision ◽

Reference Intervals ◽

Healthy Children ◽

Confidence Limits ◽

Test Results ◽

Serum Samples ◽

Abbott Architect

Abstract Objectives The Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) has developed an extensive database of reference intervals (RIs) for several biomarkers on various analytical systems. In this study, pediatric RIs were verified for key immunoassays on the Abbott Alinity system based on the analysis of healthy children samples and comparison to comprehensive RIs previously established for Abbott ARCHITECT assays. Methods Analytical performance of Alinity immunoassays was first assessed. Subsequently, 100 serum samples from healthy children recruited with informed consent were analyzed for 16 Alinity immunoassays. The percentage of test results falling within published CALIPER ARCHITECT reference and confidence limits was determined. If ≥ 90% of test results fell within the confidence limits, they were considered verified based on CLSI guidelines. If <90% of test results fell within the confidence limits, additional samples were analyzed and new Alinity RIs were established. Results Of the 16 immunoassays assessed, 13 met the criteria for verification with test results from ≥ 90% of healthy serum samples falling within the published ARCHITECT confidence limits. New CALIPER RIs were established for free thyroxine and prolactin on the Alinity system. Estradiol required special considerations in early life. Conclusions Our data demonstrate excellent concordance between ARCHITECT and Alinity immunoassays, as well as the robustness of previously established CALIPER RIs for most immunoassays, eliminating the need for de novo RI studies for most parameters. Availability of pediatric RIs for immunoassays on the Alinity system will assist clinical laboratories using this new platform and contribute to improved clinical decision-making.

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Evidence for the use of the Alere Afinion™ AS100 for measuring the levels of C-reactive protein in an elderly South African population

Journal of Medical Laboratory Science & Technology of South Africa ◽

10.36303/jmlstsa.2020.2.2.45 ◽

2020 ◽

pp. 71-76

Author(s):

I Mpofana ◽

M Nyirenda ◽

N Abbai

Keyword(s):

Linear Regression Analysis ◽

Reference Method ◽

Altman Analysis ◽

Concordance Correlation ◽

Excellent Correlation ◽

C Reactive Protein ◽

Serum Samples ◽

Cvd Risk ◽

Bland Altman Analysis ◽

Reactive Protein

Introduction: This study evaluated the performance of the Alere Afinion™ AS100 analyser for the measurement of C-reactive protein (CRP) levels in a population of older adults from South Africa. Methods: This study was a sub-study of the Sexual Health, HIV infection and comorbidity with non-communicable diseases among Older Persons (SHIOP) study. The median age of SHIOP participants was 61 years (interquartile range 12). Serum samples collected through SHIOP were used to measure CRP levels on the Alere Afinion™ AS100 (Point-of-care) and ABX Pentra 400 (reference method), respectively. Bland–Altman analysis and Lin’s concordance correlation coefficients were used to assess the agreement between the two analysers. Results: A total of 183 serum samples were tested in the study. The Alere Afinion™ AS100 median values for CRP were 9.5 mg/L and 11.5 mg/L in women and men respectively (p = 0.275). The ABX Pentra 400 median levels were lower with 5.6 mg/L and 3.6 mg/L for women and men (p = 0.027), respectively. Bland–Altman analysis and linear regression analysis showed an excellent correlation between the Pentra and Afinion analysers, with a Lin’s concordance correlation coefficient of 0.971. The Alere Afinion™ AS100 was able to correctly classify > 90% (165/183) of the CRP results when compared to the ABX Pentra 400. Conclusion: This study showed that the Alere Afinion™ AS100 had an excellent correlation with a standard laboratory method. However, the Afinion™ AS100 did not correlate well at elevated CRP levels. This may not be clinically significant since the cut-points for CVD risk are at much lower levels.

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Comparison of activated clotting times measured using the Hemochron Jr. Signature and Medtronic ACT Plus during cardiopulmonary bypass with acute normovolemic haemodilution

Journal of International Medical Research ◽

10.1177/0300060517731952 ◽

2017 ◽

Vol 46 (2) ◽

pp. 873-882 ◽

Cited By ~ 3

Author(s):

Jung Min Lee ◽

Eun Young Park ◽

Kyung Mi Kim ◽

Jong Chan Won ◽

Tack Koon Jung ◽

...

Keyword(s):

Regression Analysis ◽

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Bolus Dose ◽

Blood Glucose Concentration ◽

Altman Analysis ◽

Clotting Time ◽

Bland Altman Analysis ◽

Activated Clotting Time ◽

Protamine Administration

Objective This study compared the activated clotting time (ACT) measured using the Hemochron Jr. Signature (HACT) with the ACT measured using the Medtronic ACT Plus (MACT) during cardiopulmonary bypass (CPB) with acute normovolemic haemodilution (ANH) in patients undergoing cardiac surgery. Methods The ACT was checked at baseline with both devices after inducing anaesthesia, and 400 to 800 mL of whole blood was withdrawn to induce moderate ANH. Before initiating CPB, a 300-IU/kg bolus dose of heparin was administered to maintain the HACT at >400 s; protamine was later given to reverse the anticoagulation. The ACT was checked using both devices at baseline, during heparinisation, and after protamine administration. Results In total, 106 pairs of samples from 29 patients were analysed. The ACT showed a good correlation between the two devices (r = 0.956). However, Bland–Altman analysis showed that the MACT was higher, particularly at baseline and during heparinisation. Multiple regression analysis showed that the blood glucose concentration significantly influenced the differences between the two ACT devices. Conclusions The HACT was lower than the MACT during CPB with ANH in patients undergoing cardiac surgery. Clinicians should be cautious when using each ACT device within generally accepted reference ACT values.

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A method comparison study of a point-of-care blood gas analyser with a laboratory auto-analyser for the determination of potassium concentrations during hyperkalaemia in patients with kidney disease

Biochemia Medica ◽

10.11613/bm.2020.030702 ◽

2020 ◽

Vol 30 (3) ◽

pp. 432-438

Author(s):

Mogamat-Yazied Chothia ◽

Patricia Kassum ◽

Annalise Zemlin

Keyword(s):

Regression Analysis ◽

Systematic Error ◽

Potassium Concentration ◽

Point Of Care ◽

Venous Blood ◽

Mean Difference ◽

Renal Unit ◽

Blood Gas ◽

Altman Analysis ◽

Bland Altman Analysis

Introduction: Hyperkalaemia is a common electrolyte disorder that may cause life-threatening cardiac arrythmias. We aimed to determine the agreement of potassium concentrations between GEM premier 3500 point-of-care blood gas analyser (POC-BGA) and Roche Cobas 6000 c501 autoanalyser in patients with hyperkalaemia. Methods: A prospective, cross-sectional study of all consecutive adult patients referred to the Renal Unit with a serum potassium concentration ≥ 5.5 mmol/L was performed. A total of 59 paired venous blood samples were included in the final statistical analysis. Passing-Bablok regression and Bland Altman analysis were used to compare the two methods. Results: The median laboratory auto-analyser potassium concentration was 6.1 (5.9-7.1) mmol/L as compared to the POC-BGA potassium concentration of 5.7 (5.5-6.8) mmol/L with a mean difference of - 0.43 mmol/L and 95% upper and lower limits of agreement of 0.35 mmol/L and - 1.21 mmol/L, respectively. Regression analysis revealed proportional systematic error. Test for linearity did not indicate significant deviation (P = 0.297). Conclusion: Although regression analysis indicated proportional systematic error, on Bland Altman analysis, the mean difference appeared to remain relatively constant across the potassium range that was evaluated. Therefore, in patients presenting to the emergency department with a clinical suspicion of hyperkalaemia, POC-BGA potassium concentrations may be considered a surrogate for laboratory auto-analyser measurements once clinicians have been cautioned about this difference.

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Novel biomarker signatures for idiopathic REM sleep behavior disorder

Neurology ◽

10.1212/wnl.0000000000006439 ◽

2018 ◽

Vol 91 (18) ◽

pp. e1710-e1715 ◽

Cited By ~ 10

Author(s):

Stefania Mondello ◽

Firas Kobeissy ◽

Yehia Mechref ◽

Jingfu Zhao ◽

Farid R. Talih ◽

...

Keyword(s):

Rem Sleep ◽

Clinical Decision Making ◽

Rem Sleep Behavior Disorder ◽

Behavior Disorder ◽

Clinical Decision ◽

Serum Levels ◽

Serum Samples ◽

Proteomics Analysis ◽

Sleep Behavior ◽

Altered Expression

ObjectiveTo perform a rigorous in-depth proteomics analysis to identify circulating biomarker signatures for idiopathic REM sleep behavior disorder (RBD), capable of providing new insights into the underlying pathogenic mechanisms and putative α-synuclein-related neurodegenerative processes.MethodsSerum samples from patients with idiopathic RBD (n = 9) and healthy controls (n = 10) were subjected to a thorough liquid chromatography–mass spectrometry (MS)/MS proteomics analysis using ultimate 3,000 nanoLC interfaced to an ESI-orbitrap velos. Data were analyzed with a systems biology approach to identify altered pathways in RBD.ResultsWe identified 259 proteins, 11 of which displayed significantly altered expression level in patients with RBD as compared to controls. Significant reduction in serum levels of dopamine β-hydroxylase (DBH) and vitamin D binding protein (GC) were consistent with alterations in the norepinephrinergic (NErgic) and dopaminergic systems, respectively. Additional altered protein profiles indicated that immunity, inflammation, complement, and coagulation also play a role in RBD pathophysiology.ConclusionsOur results shed light on the protein signature profile, molecular pathways, and mechanisms involved in the pathogenesis of RBD and its clinical manifestation. This knowledge opens a new avenue towards more accurate and timely diagnosis and characterization of RBD, which might ultimately translate into new therapeutic strategies with disease-modifying effects. Further evaluation of the identified markers is required to confirm their diagnostic value and potential to guide clinical decision-making.

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Paediatric reference intervals for 17 Roche cobas 8000 e602 immunoassays in the CALIPER cohort of healthy children and adolescents

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2019-0707 ◽

2019 ◽

Vol 57 (12) ◽

pp. 1968-1979 ◽

Cited By ~ 2

Author(s):

Mary Kathryn Bohn ◽

Victoria Higgins ◽

Shervin Asgari ◽

Felix Leung ◽

Barry Hoffman ◽

...

Keyword(s):

Children And Adolescents ◽

Reference Values ◽

Laboratory Tests ◽

Clinical Decision Making ◽

Reference Intervals ◽

Healthy Children ◽

Serum Samples ◽

Clinical Laboratories ◽

Age And Sex ◽

Roche Cobas

Abstract Background The diagnostic utility of laboratory tests in paediatric medicine relies heavily on the availability of appropriate reference intervals (RIs). The Canadian Laboratory Initiative on Paediatric Reference Intervals (CALIPER) has established a comprehensive database of covariate-stratified RIs for many paediatric laboratory tests using a large, healthy reference population. Several automated analysers in widespread use in clinical laboratories have already been studied. Here, we extend the testing to Roche immunoassays and report, for the first time, comprehensive paediatric RIs for 17 endocrine and special chemistry markers. Methods A total of 741 healthy children and adolescents (1 day to <19 years) were recruited and serum samples were analysed for 17 immunoassays on the Roche cobas 8000 e602 Immunoassay Analyzer. Age and sex-specific RIs were established and corresponding 90% confidence intervals (CIs) were calculated in accordance with Clinical and Laboratory Standards Institute guidelines. Results Reference values for all analytes measured required age partitioning, particularly during early life and throughout adolescence. Of the 17 analytes measured, eight required sex partitioning, including ferritin, thyroid stimulating hormone (TSH), total triiodothyronine (TT3) and all fertility/sex hormones, except prolactin. Conclusions This is the first study to determine accurate paediatric RIs for Roche immunoassays. RIs were generally similar to those previously published by CALIPER on other analytical platforms, highlighting the reproducibility of age- and sex-specific trends in reference values observed across the paediatric age range. The RIs established in this study will improve the accuracy of test result interpretation and clinical decision-making in clinical laboratories utilising Roche immunoassays.

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A new strategy implementing mass spectrometry in the diagnosis of congenital disorders of N-glycosylation (CDG)

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2020-0650 ◽

2021 ◽

Vol 59 (1) ◽

pp. 165-171

Author(s):

Bruno Casetta ◽

Sabrina Malvagia ◽

Silvia Funghini ◽

Diego Martinelli ◽

Carlo Dionisi-Vici ◽

...

Keyword(s):

Mass Spectrometry ◽

Clinical Decision Making ◽

Clinical Decision ◽

Congenital Disorders ◽

Type I ◽

Post Translational Modification ◽

Serum Samples ◽

Mass Spectrometric Measurement ◽

Classical Procedure ◽

New Strategy

AbstractObjectivesCongenital disorders of N-glycosylation (CDG) are a large group of rare metabolic disorders caused by defects in the most common post-translational modification of proteins. CDGs are often difficult to diagnose as they are manifested with non-specific symptoms and signs. Analysis of serum transferrin (TRF) isoforms, as the classical procedure used to identify a CDG patient, enables to predict pathological steps in the N-linked glycosylation process.MethodsWe devised a new strategy based on liquid chromatography-mass spectrometry (LC-MS) for the analysis of TRF isoforms by combining a simple and fast sample preparation with a specific chromatographic cleanup/separation step followed by mass-spectrometric measurement. Single TRF isoform masses were obtained through reconstruction of multiply charged electrospray data collected by quadrupole-MS technology. Hereby, we report the first analyzed serum samples obtained from 20 CDG patients and 100 controls.ResultsThe ratio of desialylated isoforms to total TRF was calculated for patients and controls. CDG-Type I patients showed higher amounts of bi-sialo isoform (range: 6.7–29.6%) compared to controls (<5.5%, mean percentage 3.9%). CDG-Type II pattern showed an increased peak of tri-sialo isoforms. The mean percentage of tri-sialo-TRF was 9.3% (range: 2.9–12.9%) in controls, which was lower than that obtained from two patients with COG5-CDG and MAN1B1-CDG (18.5 and 24.5%). Intraday and between-day imprecisions were less than 9 and 16%, respectively, for bi-sialo- and less than 3 and 6% for tri-sialo-TRF.ConclusionsThis LC-MS-based approach provides a simple, sensitive and fast analytical tool for characterizing CDG disorders in a routine clinical biochemistry while improving diagnostic accuracy and speeding clinical decision-making.

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Multicenter comparison of the Cobas 6800 system with the RealStar RT-PCR kit for the detection of SARS-CoV-2

10.1101/2020.06.29.179184 ◽

2020 ◽

Author(s):

Marc Wirden ◽

Linda Feghoul ◽

Mélanie Bertine ◽

Marie-Laure Nere ◽

Quentin Le Hingrat ◽

...

Keyword(s):

Regression Analysis ◽

Linear Regression Analysis ◽

Regression Line ◽

Clinical Samples ◽

Altman Analysis ◽

Rt Pcr ◽

Bland Altman Analysis ◽

Deming Regression ◽

The Mean ◽

Pcr Assays

ABSTRACTBackgroundRT-PCR testing is crucial in the diagnostic of SARS-CoV-2 infection. The use of reliable and comparable PCR assays is a cornerstone to allow use of different PCR assays depending on the local equipment. In this work, we provide a comparison of the Cobas® (Roche) and the RealStar® assay (Altona).MethodsAssessment of the two assays was performed prospectively in three reference Parisians hospitals, using 170 clinical samples. They were tested with the Cobas® assay, selected to obtain a distribution of cycle threshold (Ct) as large as possible, and tested with the RealStar assay with three largely available extraction platforms: QIAsymphony (Qiagen), MagNAPure (Roche) and NucliSENS-easyMag (BioMérieux).ResultsOverall, the agreement (positive for at least one gene) was 76%. This rate differed considerably depending on the Cobas Ct values for gene E: below 35 (n = 91), the concordance was 99%. Regarding the positive Ct values, linear regression analysis showed a determination correlation (R2) of 0.88 and the Deming regression line revealed a strong correlation with a slope of 1.023 and an intercept of -3.9. Bland-Altman analysis showed that the mean difference (Cobas® minus RealStar®) was + 3.3 Ct, with a SD of + 2.3 Ct.ConclusionsIn this comparison, both RealStar® and Cobas® assays provided comparable qualitative results and a high correlation when both tests were positive. Discrepancies exist after 35 Ct and varied depending on the extraction system used for the RealStar® assay, probably due to a low viral load close to the detection limit of both assays.

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The Activin/Follistatin-axis is severely deregulated in COVID-19 and independently associated with in-hospital mortality

10.1101/2020.09.05.20184655 ◽

2020 ◽

Author(s):

Evgenia Synolaki ◽

Vasileios Papadopoulos ◽

Georgios Divolis ◽

Olga Tsahouridou ◽

Efstratios Gavriilidis ◽

...

Keyword(s):

Clinical Decision Making ◽

Fatal Outcome ◽

Clinical Decision ◽

Activin A ◽

Serum Samples ◽

Dynamic Prediction ◽

Neutrophil Lymphocyte Ratio ◽

Over Expression ◽

Initial Cohort ◽

Natural Inhibitor

AbstractBackgroundActivins are members of the TGFβ-superfamily implicated in the pathogenesis of several immuno-inflammatory disorders. Based on our previous studies demonstrating that over-expression of Activin-A in murine lung causes pathology sharing key features of COVID-19, we hypothesized that Activins and their natural inhibitor Follistatin might be particularly relevant to COVID-19 pathophysiology.MethodsActivin-A, Activin-B and Follistatin levels were retrospectively analyzed in 574 serum samples from 263 COVID-19 patients hospitalized in three independent centers, and compared with common demographic, clinical and laboratory parameters. Optimal-scaling with ridge-regression was used to screen variables and establish a prediction model.ResultThe Activin/Follistatin-axis was significantly deregulated during the course of COVID-19, correlated with severity and independently associated with mortality. FACT-CLINYCoD, a novel disease scoring system, adding one point for each of Follistatin>6235pg/ml, Activin-A>591pg/ml, Activin-B>249pg/ml, CRP>10.3mg/dL, LDH>427U/L, Intensive Care Unit (ICU) admission, Neutrophil/Lymphocyte-Ratio>5.6, Years of Age>61, Comorbidities>1 and D-dimers>1097ng/ml, efficiently predicted fatal outcome in an initial cohort (AUC: 0.951±0.032, p<10−6). Two independent cohorts that were used for validation indicated comparable AUC (0.958, p=0.880 and 0.924, p=0.256, respectively).ConclusionsThis study unravels strong link between Activin/Follistatin-axis and COVID-19 mortality and introduces FACT-CLINYCoD, a novel pathophysiology-based tool that allows dynamic prediction of disease outcome, supporting clinical decision making.

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