scholarly journals Analytical Interference by Contrast Agents in Biochemical Assays

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Sigrid Otnes ◽  
Niels Fogh-Andersen ◽  
Janne Rømsing ◽  
Henrik S. Thomsen
Keyword(s):  
Lactate Dehydrogenase ◽  
Contrast Agents ◽  
Blood Test ◽  
Test Results ◽  
Gadoxetate Disodium ◽  
Negative Interference ◽  
Analytical Interference ◽  
Biochemical Assays ◽  
Gadoterate Meglumine ◽  
Positive Interference

Objective.To provide a clinically relevant overview of the analytical interference by contrast agents (CA) in laboratory blood test measurements.Materials and Methods.The effects of five CAs, gadobutrol, gadoterate meglumine, gadoxetate disodium, iodixanol, and iomeprol, were studied on the 29 most frequently performed biochemical assays. One-day-old plasma, serum, and whole blood were spiked with doses of each agent such that the gadolinium agents and the iodine agents reached concentrations of 0.5 mM and 12 mg iodine/mL, respectively. Subsequently, 12 assays were reexamined using1/2and1/4of these CA concentrations. The results were assessed statistically by a paired Student’st-test.Results.Iodixanol produced a negative interference on the bicarbonate (p=0.011), lactate dehydrogenase (p<0.0001), and zinc (p=0.0034) assays and a positive interference on the albumin (p=0.0062), calcium (p<0.0001), ionized calcium (p=0.0086), iron (p<0.0001), and potassium (p=0.0003) assays. Iomeprol produced a negative interference on the bicarbonate (p=0.0057) and magnesium (p=0.0001) assays and a positive interference on the calcium (p<0.0001) and potassium (p=0.0012) assays. Gadoxetate disodium produced a negative interference on the iron (p<0.0001) and zinc (p<0.0001) assays and a positive interference on the sodium (p=0.032) assay.Conclusion.CAs cause analytical interference. Attention should be given to the above-mentioned analyte-CA combinations when assessing laboratory blood test results obtained after CA administration.

scholarly journals Heterofile antistoffer - en kilde til analyseinterferens

2009 ◽  
Vol 16 (1) ◽  
Author(s):  
Johan Bjerner ◽  
Kjell Nustad
Keyword(s):  
Heterophilic Antibodies ◽  
Negative Interference ◽  
Human Antibodies ◽  
Analytical Interference ◽  
Positive Interference

<p> Sirkulerende naturlig forekommende humane antistoffer mot humane antistoffer (rheumatoide faktorer) og mot dyreantistoffer (heterofile antistoffer) har evner til å binde analyseantistoffer som brukes i en immunometrisk analyse. Resultatet er oftest et falsk forhøyet prøvesvar (positiv interferens) og noen ganger et falsk for lavt svar (negativ interferens). Slik interferens kan reduseres betydelig gjennom modifisering av analyseantistoffene og gjennom buffertilsetninger, men forekomsten av interferens kan i dag ikke helt elimineres. Det er derfor viktig at klinikeren kjenner til risikoen for interferens, og gir laboratoriet tilbakemelding dersom prøvesvaret ikke stemmer med klinikken</p><p><em>Heterophilic antibodies – a source of analytical interference</em>. Human antibodies binding human or animal antibodies may cause aberrant results in immunometric assays by binding the assay antibodies involved. The result may be falsely elevated (positive interference) or falsely low (negative interference). Both the frequency and the size of the aberrations may be reduced by either modifying the assay antibodies or by using buffer additives. However, as such interference cannot be completely eradicated, awareness of physicans and scientists is strongly needed.</p>

scholarly journals Respiratory anomalies associated with gadoxetate disodium and gadoterate meglumine: compressed sensing MRI revealing physiologic phenomena during the entire injection cycle

2021 ◽  
Author(s):  
Carl Guillaume Glessgen ◽  
Hanns-Christian Breit ◽  
Tobias Kai Block ◽  
Elmar Max Merkle ◽  
Tobias Heye ◽  
...  
Keyword(s):  
Contrast Agents ◽  
Temporal Correlation ◽  
Arterial Phase ◽  
Phase Imaging ◽  
Gadoxetate Disodium ◽  
Respiratory Events ◽  
Cardiac Ventricle ◽  
Gadoterate Meglumine ◽  
Time Changes ◽  
The Right

Abstract Objectives The goal of this study was to investigate the precise timeline of respiratory events occurring after the administration of two gadolinium-based contrast agents, gadoxetate disodium and gadoterate meglumine. Materials and methods This retrospective study examined 497 patients subject to hepatobiliary imaging using the GRASP MRI technique (TR/TE = 4/2 ms; ST = 2.5 mm; 384 × 384 mm). Imaging was performed after administration of gadoxetate (N = 338) and gadoterate (N = 159). All GRASP datasets were reconstructed using a temporal resolution of 1 s. Four regions-of-interest (ROIs) were placed in the liver dome, the right and left cardiac ventricle, and abdominal aorta detecting liver displacement and increasing vascular signal intensities over time. Changes in hepatic intensity reflected respiratory dynamics in temporal correlation to the vascular contrast bolus. Results In total, 216 (67%) and 41 (28%) patients presented with transient respiratory motion after administration of gadoxetate and gadoterate, respectively. The mean duration from start to acme of the respiratory episode was similar (p = 0.4) between gadoxetate (6.0 s) and gadoterate (5.6 s). Its mean onset in reference to contrast arrival in the right ventricle differed significantly (p < 0.001) between gadoxetate (15.3s) and gadoterate (1.8 s), analogously to peak inspiration timepoint in reference to the aortic enhancement arrival (gadoxetate: 0.9s after, gadoterate: 11.2 s before aortic enhancement, p < 0.001). Conclusions The timepoint of occurrence of transient respiratory anomalies associated with gadoxetate disodium and gadoterate meglumine differs significantly between both contrast agents while the duration of the event remains similar. Key Points • Transient respiratory anomalies following the administration of gadoterate meglumine occurred during a time period usually not acquired in MR imaging. • Transient respiratory anomalies following the administration of gadoxetate disodium occurred around the initiation of arterial phase imaging. • The estimated duration of respiratory events was similar between both contrast agents.

scholarly journals The use of routine blood tests to assist the diagnosis of COVID-19 in symptomatic hospitalized patients

2021 ◽  
pp. 000456322199907
Author(s):  
IT Parsons ◽  
AT Parsons ◽  
E Balme ◽  
G Hazell ◽  
R Gifford ◽  
...  
Keyword(s):  
Cell Count ◽  
Retrospective Review ◽  
Blood Test ◽  
Patient Flow ◽  
White Cell Count ◽  
Area Under The Curve ◽  
White Cell ◽  
Test Results ◽  
Rt Pcr ◽  
Blood Tests

Introduction Specific patterns of blood test results are associated with COVID-19 infection. The aim of this study was to identify which blood tests could be used to assist in diagnosing COVID-19. Method A retrospective review was performed on consecutive patients referred to hospital with a clinical suspicion of COVID-19 over a period of four weeks. The patient’s clinical presentation and severe acute respiratory syndrome coronavirus 2 reverse-transcription polymerase chain reaction (SARS-CoV-2 RT-PCR) were recorded. The patients were divided by diagnosis into COVID (COVID-19 infection) or CONTROL (an alternate diagnosis). A retrospective review of consecutive patients over a further two-week period was used for the purposes of validation. Results Overall, 399 patients (53% COVID, 47% CONTROL) were analysed. White cell count, neutrophils and lymphocytes were significantly lower, while lactate dehydrogenase and ferritin were significantly higher, in the COVID group in comparison to CONTROL. Combining the white cell count, lymphocytes and ferritin results into a COVID Combined Blood Test (CCBT) had an area under the curve of 0.79. Using a threshold CCBT of –0.8 resulted in a sensitivity of 0.85 and a specificity of 0.63. Analysing this against a further retrospective review of 181 suspected COVID-19 patients, using the same CCBT threshold, resulted in a sensitivity of 0.73 and a specificity of 0.75. The sensitivity was comparable to the SARS-CoV-2 RT PCR. Discussion Mathematically combining the blood tests has the potential to assist clinical acumen allowing for rapid streaming and more accurate patient flow pending definitive diagnosis. This may be of particular use in low-resource settings.

Predicting abnormal laboratory blood test results in the intensive care unit using novel features based on information theory and historical conditional probability (Preprint)

2021 ◽  
Author(s):  
Camilo E. Valderrama ◽  
Daniel J. Niven ◽  
Henry T. Stelfox ◽  
Joon Lee
Keyword(s):  
Machine Learning ◽  
Intensive Care ◽  
Conditional Probability ◽  
Blood Test ◽  
Laboratory Tests ◽  
Conditional Entropy ◽  
Admission Diagnosis ◽  
Test Results ◽  
Abnormal Laboratory ◽  
Blood Tests

BACKGROUND Redundancy in laboratory blood tests is common in intensive care units (ICU), affecting patients' health and increasing healthcare expenses. Medical communities have made recommendations to order laboratory tests more judiciously. Wise selection can rely on modern data-driven approaches that have been shown to help identify redundant laboratory blood tests in ICUs. However, most of these works have been developed for highly selected clinical conditions such as gastrointestinal bleeding. Moreover, features based on conditional entropy and conditional probability distribution have not been used to inform the need for performing a new test. OBJECTIVE We aimed to address the limitations of previous works by adapting conditional entropy and conditional probability to extract features to predict abnormal laboratory blood test results. METHODS We used an ICU dataset collected across Alberta, Canada which included 55,689 ICU admissions from 48,672 patients with different diagnoses. We investigated conditional entropy and conditional probability-based features by comparing the performances of two machine learning approaches to predict normal and abnormal results for 18 blood laboratory tests. Approach 1 used patients' vitals, age, sex, admission diagnosis, and other laboratory blood test results as features. Approach 2 used the same features plus the new conditional entropy and conditional probability-based features. RESULTS Across the 18 blood laboratory tests, both Approach 1 and Approach 2 achieved a median F1-score, AUC, precision-recall AUC, and Gmean above 80%. We found that the inclusion of the new features statistically significantly improved the capacity to predict abnormal laboratory blood test results in between ten and fifteen laboratory blood tests depending on the machine learning model. CONCLUSIONS Our novel approach with promising prediction results can help reduce over-testing in ICUs, as well as risks for patients and healthcare systems. CLINICALTRIAL N/A

Diseases

1932 ◽  
Vol 5 (3-4) ◽  
pp. 73-130
Keyword(s):  
No Value ◽  
Blood Test ◽  
Agglutination Test ◽  
Test Results ◽  
Agglutination Titer ◽  
Poultry Farmers

Value of Agglutination-Test. - Der Wert der Agglutinations Methode bei der weissen Ruhr. Dr. Sachweh, München. Berliner Tierärztliche Wochenschrift, 1931, p. 845.A number of chickens were subjected, every three months, to the agglutination test. During this test it appeared that the agglutination titer varied considerably. All animals, of which a great number reacted positively at the beginning of the test, reacted negatively at the end thereof. This made it possible to comprehend the strongly varying results of the different tests. A group of 400 positive reacting hens gave healthy chicks. The wide advertising of the rapid blood test results in the poultry farmers making their own researches, and owing to the varying results obtained, it forces them to attach no value thereto.

scholarly journals Early Cancer Detection from Multianalyte Blood Test Results

iScience ◽  
2019 ◽  
Vol 15 ◽  
pp. 332-341 ◽  
Author(s):  
Ka-Chun Wong ◽  
Junyi Chen ◽  
Jiao Zhang ◽  
Jiecong Lin ◽  
Shankai Yan ◽  
...  
Keyword(s):  
Cancer Detection ◽  
Blood Test ◽  
Early Cancer ◽  
Early Cancer Detection ◽  
Test Results
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