scholarly journals Reference change value and measurement uncertainty of CRP, ferritin, procalcitonin, troponin I and BNP tests in COVID-19 monitoring: how much change matters?

2021 ◽  
Author(s):  
nergiz zorbozan
Keyword(s):  
Measurement Uncertainty ◽  
Troponin I ◽  
Reference Change Value

Reference change value and measurement uncertainty in the evaluation of tumor markers

2021 ◽  
pp. 1-5
Author(s):  
Hatice Bozkurt Yavuz ◽  
Mehmet Akif Bildirici ◽  
Hüseyin Yaman ◽  
Süleyman Caner Karahan ◽  
Yüksel Aliyazıcıoğlu ◽  
...  
Keyword(s):  
Measurement Uncertainty ◽  
Tumor Markers ◽  
Reference Change Value

scholarly journals Biological variation of cardiac troponins in chronic kidney disease

2020 ◽  
Vol 57 (2) ◽  
pp. 162-169
Author(s):  
RA Jones ◽  
J Barratt ◽  
EA Brettell ◽  
P Cockwell ◽  
RN Dalton ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
Biological Variation ◽  
Cardiac Troponin I ◽  
Cardiac Troponin T ◽  
Reference Change Value

Background Patients with chronic kidney disease often have increased plasma cardiac troponin concentration in the absence of myocardial infarction. Incidence of myocardial infarction is high in this population, and diagnosis, particularly of non ST-segment elevation myocardial infarction (NSTEMI), is challenging. Knowledge of biological variation aids understanding of serial cardiac troponin measurements and could improve interpretation in clinical practice. The National Academy of Clinical Biochemistry (NACB) recommended the use of a 20% reference change value in patients with kidney failure. The aim of this study was to calculate the biological variation of cardiac troponin I and cardiac troponin T in patients with moderate chronic kidney disease (glomerular filtration rate [GFR] 30–59 mL/min/1.73 m2). Methods and results Plasma samples were obtained from 20 patients (median GFR 43.0 mL/min/1.73 m2) once a week for four consecutive weeks. Cardiac troponin I (Abbott ARCHITECT® i2000SR, median 4.3 ng/L, upper 99th percentile of reference population 26.2 ng/L) and cardiac troponin T (Roche Cobas® e601, median 11.8 ng/L, upper 99th percentile of reference population 14 ng/L) were measured in duplicate using high-sensitivity assays. After outlier removal and log transformation, 18 patients’ data were subject to ANOVA, and within-subject (CVI), between-subject (CVG) and analytical (CVA) variation calculated. Variation for cardiac troponin I was 15.0%, 105.6%, 8.3%, respectively, and for cardiac troponin T 7.4%, 78.4%, 3.1%, respectively. Reference change values for increasing and decreasing troponin concentrations were +60%/–38% for cardiac troponin I and +25%/–20% for cardiac troponin T. Conclusions The observed reference change value for cardiac troponin T is broadly compatible with the NACB recommendation, but for cardiac troponin I, larger changes are required to define significant change. The incorporation of separate RCVs for cardiac troponin I and cardiac troponin T, and separate RCVs for rising and falling concentrations of cardiac troponin, should be considered when developing guidance for interpretation of sequential cardiac troponin measurements.

scholarly journals Prognostic Value of Serial Changes in High-Sensitivity Cardiac Troponin I and T over 3 Months Using Reference Change Values in Hemodialysis Patients

2016 ◽  
Vol 62 (4) ◽  
pp. 631-638 ◽  
Author(s):  
Yader Sandoval ◽  
Charles A Herzog ◽  
Sara A Love ◽  
Jing Cao ◽  
Yan Hu ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Prognostic Value ◽  
Troponin I ◽  
High Sensitivity ◽  
Cardiac Troponin I ◽  
Adverse Outcomes ◽  
Cox Models ◽  
Reference Change Value ◽  
Hazard Ratios ◽  
All Cause Mortality

Abstract INTRODUCTION Serial changes in cardiac troponin in hemodialysis (HD) patients have uncertain clinical implications. We evaluated associations of adverse outcomes in HD patients with reference change value (RCV) data and tertile concentrations for cardiac troponin I (cTnI) and cTnT measured by high-sensitivity (hs) assays. METHODS RCV data and tertiles for hs-cTnI and hs-cTnT were determined from plasma samples collected 3 months apart in 677 stable outpatient HD patients and assessed for their associations with adverse outcomes using adjusted Cox models. Primary outcomes were all-cause mortality and sudden cardiac death (SCD). RESULTS During a median follow-up of 23 months, 18.6% of patients died. RCVs were: hs-cTnI +37% and −30%; hs-cTnT +25% and −20%. Patients with serial hs-cTnI and hs-cTnT changes >RCV (increase or decrease) had all-cause mortality of 25.2% and 23.8% respectively, compared to 15.0% and 16.5% with changes ≤RCV [adjusted hazard ratios (aHRs): 1.9, P = 0.0003 and 1.7, P = 0.0066), respectively]. Only hs-cTnI changes >RCV were predictive of SCD (aHR 2.6, P = 0.005). hs–Cardiac troponin changes >RCV improved all-cause mortality prognostication compared to changes ≤RCV in tertile 2: hs-cTnI aHR, 2.70 (P = 0.003); hs-cTnT aHR, 1.98 (P = 0.043). The aHR of changes in hs-cTnI in tertile 2 >RCV for SCD was 5.62 (P = 0.039). CONCLUSIONS Changes over 3 months in hs-cTnI and hs-cTnT of >RCV identified patients at greater risk of all-cause mortality, and for hs-cTnI were also predictive of SCD. Among patients with middle tertile cardiac troponin concentrations, hs-cTnI changes >RCV provided additive prognostic value for both SCD and all-cause mortality, whereas those for hs-cTnT provided additive prognostic value only for all-cause mortality.

Longitudinal Studies of Cardiac Troponin-I Concentrations in Serum from Male Sprague Dawley Rats: Baseline Reference Ranges and Effects of Handling and Placebo Dosing on Biological Variability

2009 ◽  
Vol 37 (6) ◽  
pp. 754-760 ◽  
Author(s):  
A. Eric Schultze ◽  
Kent H. Carpenter ◽  
Frank H. Wians ◽  
Sara J. Agee ◽  
Jennifer Minyard ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Cardiac Troponin I ◽  
Assay Method ◽  
Healthy Population ◽  
Reference Ranges ◽  
Biological Variability ◽  
Standard Laboratory ◽  
Rat Serum ◽  
Reference Change Value

Serum cardiac troponin-I has been validated as a biomarker for cardiotoxicity in numerous animal models; however, baseline reference ranges for cTnI concentration in a healthy population of laboratory rats, as well as an investigation of biological cTnI variability in rats with respect to time, handling, and placebo dosing methods, have not been reported. In this study, we used an ultrasensitive cTnI immunoassay to quantify hourly concentrations of cTnI in live rats handled under standard laboratory conditions using 15 μL of serum per determination. The baseline reference range (mean 4.94 pg/mL, range 1–15 pg/mL, 99% confidence interval [CI]) of cTnI concentration in rats was consistent with previously reported reference ranges for cTnI in humans (1–12 pg/mL) and with preliminary studies in dogs (1–4 pg/mL) and monkeys (4–5 pg/mL) using the same cTnI assay method. In addition, cTnI concentrations in individual rat serum samples show minimal biological variability over a twenty-four-hour interval when compared to a meaningful reference change value of 193% to 206%. Furthermore, measurements of cTnI concentration were consistent within the reference limits in individual rats over long periods and under three different standard laboratory handling conditions. Thus, using this new method, rats can be followed longitudinally at hourly intervals, and a doubling of cTnI concentration would be significant above biological variability. This is a new paradigm for preclinical testing, which allows transient changes in cTnI concentration to be accurately quantified. This understanding of baseline and biological variability in rats will be fundamental for designing and analyzing future studies that assess potential cardiotoxicity in drug development.

scholarly journals Weekly and 90-Minute Biological Variations in Cardiac Troponin T and Cardiac Troponin I in Hemodialysis Patients and Healthy Controls

2014 ◽  
Vol 60 (6) ◽  
pp. 838-847 ◽  
Author(s):  
Kristin M Aakre ◽  
Thomas Røraas ◽  
Per Hyltoft Petersen ◽  
Einar Svarstad ◽  
Hilde Sellevoll ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
False Positive Rate ◽  
High Sensitivity ◽  
Sampling Period ◽  
Cardiac Troponin T ◽  
Healthy Individuals ◽  
Reference Change Value ◽  
Positive Rate

Abstract BACKGROUND Myocardial infarction (MI) is diagnosed by the finding of a single cardiac troponin value above the 99th percentile and a significant time-dependent change in cardiac troponin concentration. The aim of this study was to determine the 90-min and weekly biological variations, the reference change value (RCV), and the index of individuality (II) of high-sensitivity cardiac troponin T (hs-cTnT) (Roche Diagnostics) and hs-cTnI (Abbott Diagnostics) in patients receiving hemodialysis (HD) and in healthy individuals. METHOD Blood samples were collected from 19 HD patients (on an HD-free day) and 20 healthy individuals at 90-min intervals over a 6-h period (between 08:30 and 14:30) and before the midweek HD treatment for 10 weeks. The within-person variation (CVi), between-person variation, RCV, and II were calculated. RESULTS During the 6-h sampling period, the concentrations of hs-cTnT (both groups) and hs-cTnI (HD patients only) decreased on average by 0.8% to 1.7% per hour, respectively. These declining trends were included in the calculation of a 90-min asymmetric RCV: −8%/+5% in HD patients (hs-cTnT), −18%/+21% in HD patients (hs-cTnI), −27%/+29% in healthy individuals (hs-cTnT), and −39%/+64% in healthy individuals (hs-cTnI). The II was low in both groups for both assays. The weekly CVi values were approximately 8% (hs-cTnT) and 15% (hs-cTnI) in both groups. CONCLUSIONS When using a cardiac troponin change of 20%–50% to diagnose an MI, the false-positive rate is likely to be lower for the hs-cTnT assay than for the hs-cTnI assay. The low II suggests that use of a diagnostic cutoff value can be omitted.

scholarly journals Short-term increases of plasma cardiac troponin I are better evaluated by comparison with the reference change value

2010 ◽  
pp. 327-333 ◽  
Author(s):  
Giovanni Introcaso ◽  
Monica Raggi ◽  
Tiziana D'Errico ◽  
Annalisa Cavallero
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Cardiac Troponin I ◽  
Short Term ◽  
Reference Change Value

scholarly journals Longitudinal Studies of Cardiac Troponin I in a Large Cohort of Healthy Children

2012 ◽  
Vol 58 (12) ◽  
pp. 1665-1672 ◽  
Author(s):  
Gus Koerbin ◽  
Julia M Potter ◽  
Walter P Abhayaratna ◽  
Richard D Telford ◽  
Tony Badrick ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Limit Of Detection ◽  
High Sensitivity ◽  
Biological Variation ◽  
Cardiac Troponin I ◽  
Community Dwelling ◽  
Low Grade ◽  
Healthy Children ◽  
Reference Change Value

BACKGROUND There is little information available on cardiac troponin concentrations in healthy young children. METHODS Using a precommercial high-sensitivity assay from Abbott Diagnostics, we measured cardiac troponin I (cTnI) in longitudinal blood samples collected at ages 8, 10, and 12 years from a cohort of healthy, community-dwelling children. The 99th percentile values were calculated and estimates of the long-term biological variation were made. RESULTS cTnI concentrations were above the limit of detection in 87%, 90%, and 98% of the children at ages 8, 10, and 12 years. The 99th percentiles were lower compared to a healthy adult population in both male and female children at all ages studied. At the 3 periods of study assessment, different children had cTnI concentrations above the 99th percentile. The calculated 99th percentile varied markedly depending upon whether the lowest or highest cTnI measurement for an individual child was included in the calculation. Biological variation varied markedly between 0% and 136%, the index of individuality was low at 0.36, and the reference change value was an increase of 147% or a decrease of 59%. CONCLUSIONS In this longitudinal study of cTnI concentrations in healthy children as determined by a high-sensitivity assay, different children had concentrations of cTnI above the 99th percentile at the 3 episodes of assessment. These results suggest that in children the 99th percentile may not be a reliable index of silent cardiac disease, but rather may be indicating low-grade intercurrent illness.

scholarly journals The Importance of Single or Combined Use of Measurement Uncertainty and the Reference Change Value in the Diagnostic Evaluation of Biochemical Tests

2020 ◽  
Vol 1 (1) ◽  
pp. 7-16
Author(s):  
Alper Kütükçü ◽  
Fatih Özçelik ◽  
Mehmet Murat Yekrek ◽  
Şerif Kaçtaş ◽  
Mehmet Zahit Çıracı ◽  
...  
Keyword(s):  
Measurement Uncertainty ◽  
Diagnostic Evaluation ◽  
Biochemical Tests ◽  
Reference Change Value ◽  
Combined Use
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