Transitioning to high-sensitivity troponin: 1-year mortality outcomes in patients with suspected acute coronary syndrome presenting to emergency departments.

Background: Switching from a conventional to a high-sensitivity cardiac troponin (hs-cTn) assay enables detection of smaller amounts of myocardial damage, but the clinical benefit is unclear. We investigated whether switching to a hs-cTnI assay with a sex-specific 99th centile diagnostic threshold was associated with lower 1-year death or new myocardial infarction (MI) in patients with suspected acute coronary syndrome (ACS).

Methods: This pre-post study included nine tertiary hospitals in Australia.

Evaluation of Solanaceous Species as Nonhost Trap Crops for .

, the pale cyst nematode (PCN), is a quarantine pest of potato posing a serious threat to the Idaho potato industry. only hatches in the presence of a hatching stimulus produced by a host plant or closely related species. In the absence of this hatching stimulus, can remain viable in the soil for decades.

The effect of the immunoassay curve fitting routine on bias in troponin.

Objectives: Unlike many dose-response curves used in clinical chemistry, the immunoassay curve used to quantitate measurands is often sigmoidal rather than linear. Consequently, a more complex curve fitting model is required. Various models are available, but they can introduce bias, and there can be little awareness of why this error can be introduced.

Oral glucose tolerance test to diagnose gestational diabetes mellitus: Impact of variations in specimen handling.

To improve birth outcomes, all pregnant women without known diabetes are recommended for an oral glucose tolerance test (OGTT) to screen for hyperglycaemia in pregnancy (diabetes in pregnancy or gestational diabetes mellitus (GDM)). This narrative review presents contemporary approaches to minimise preanalytical glycolysis in OGTT samples with a focus on GDM diagnosis using criteria derived from the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study. The challenges of implementing each approach across a diverse Australian healthcare setting were explored.

Troponins in myocardial infarction and injury.

Troponins are proteins that are integral components of the contractile mechanism of muscle, including cardiac muscle. Cardiac troponins Iand T can be detected in the blood of most people after puberty, at concentrations reflecting cardiac mass, sex and age. Current laboratory assays are approximately 1000 times more sensitive than those used previously.

The intra-individual variation of cardiac troponin I: the effects of sex, age, climatic season, and time between samples.

Objectives: Knowing the intra-individual variation (CVi), also termed within subject biological variation, of an analyte is essential to properly interpret apparent changes in concentration. While there have been many studies assessing the CVi of cardiac troponin (cTnI), they have been limited in looking at CVi in different settings, and there is no data available on whether CVi might change in different settings.

Methods: We used our large cTnI data bank to look at the CVi of cTnI in Emergency Department (ED) patients who had an acute myocardial infarction event excluded.

Possible Cross-Reactivity of Feline and White-Tailed Deer Antibodies against the SARS-CoV-2 Receptor Binding Domain.

In late 2019, a novel coronavirus began circulating within humans in central China. It was designated SARS-CoV-2 because of its genetic similarities to the 2003 SARS coronavirus (SARS-CoV). Now that SARS-CoV-2 has spread worldwide, there is a risk of it establishing new animal reservoirs and recombination with native circulating coronaviruses.

Choice of Statistical Tools for Outlier Removal Causes Substantial Changes in Analyte Reference Intervals in Healthy Populations.

Background: Reference intervals are an important aid in medical practice as they provide clinicians a guide as to whether a patient is healthy or diseased.Outlier results in population studies are removed by any of a variety of statistical measures. We have compared several methods of outlier removal and applied them to a large body of analytes from a large population of healthy persons.

Strict Preanalytical Oral Glucose Tolerance Test Blood Sample Handling Is Essential for Diagnosing Gestational Diabetes Mellitus.

Objective: Preanalytical processing of blood samples can affect plasma glucose measurement because ongoing glycolysis by cells prior to centrifugation can lower its concentration. In June 2017, ACT Pathology changed the processing of oral glucose tolerance test (OGTT) blood samples for pregnant women from a delayed to an early centrifugation protocol. The effect of this change on the rate of gestational diabetes mellitus (GDM) diagnosis was determined.

Age-related differences in hs-cTnI concentration in healthy adults.

Background: Because the 99th percentile is of such importance in defining myocardial injury and myocardial infarction, it is important to know whether there are real age-related differences in troponin 99th percentiles.

Methods: We went to our database from the Canberra Heart Study where 1062 apparently healthy subjects were extensively screened for occult cardiac disease, and looking at persons aged <65 years and >65 years, for men and women separately, we compared a variety of cutpoints from the 99th percentile down to the 50th percentile.

Results: With our rigorous criteria for defining cardiac health, we excluded 67.

Are the changes in diagnostic criteria for gestational diabetes mellitus reflected in perinatal outcomes? A retrospective assessment.

Background: Gestational diabetes mellitus (GDM) is glucose intolerance first diagnosed during pregnancy not due to overt diabetes. Recent changes to the diagnostic guidelines have been shown to increase the apparent occurrence of GDM.

Aim: The aim of this study was to compare retrospectively the neonatal outcomes between groups defined using the new and old criteria to assess the impact of guideline changes on pregnancy outcomes.

The importance of low level QC for high sensitivity troponin assays.

Background: With the advent of the new high-sensitivity troponin assays, it is becoming critical to measure troponin accurately to low concentrations. To ensure assay performance is acceptable, appropriate QC must be run.

Methods: In addition to the routine use of commercial QC material, we prepared pools of human QC material with low troponin concentrations close to the limit of quantitation, and ran these regularly on our laboratory analysers.

The investigation of interferences in immunoassay.

Immunoassay procedures have a wide application in clinical medicine and as such are used throughout clinical biochemistry laboratories both for urgent and routine testing. Clinicians and laboratory personnel are often presented with immunoassay results which are inconsistent with clinical findings. Without a high index of suspicion interferences will often not be suspected.

'Aussie Normals': an a priori study to develop reference intervals in a healthy Australian population using the Beckman Coulter LH 750 Haematology Analyser as candidates for harmonised values.

Reference limits or intervals are important benchmarks or tools that help the clinician to distinguish between a result that is most likely to lie within a 'healthy' or diseased category. It has been suggested that a review of haematology reference intervals is long overdue. In this study we report on our findings for analytes routinely measured in a complete blood count (CBC) performed on the Beckman Coulter LH 750 analyser and an additional comparative study using the Beckman Coulter LH 750, the Sysmex XN and Abbott Sapphire.

The relationship of plasma creatinine (as eGFR) and high-sensitivity cardiac troponin and NT-proBNP concentrations in a hospital and community outpatient population.

Objectives: While persons with overt renal failure have a well-described rise in troponin and NT-proBNP, it is less well described what the relationship is between cardiac markers and persons with impaired renal function, not requiring dialysis.

Design & Methods: We have collected ALL samples referred to our pathology practice over a 24h period and measured hs-cTnI, hs-cTnT, NT-proBNP, calculated the eGFR, and related our measurements to clinical outcomes.

Results: For both men and women, for all of hs-cTnI, hs-cTnT and NT-proBNP, there was a graded response, as renal function worsened, the concentration of the cardiac marker increased.

Statistical considerations for determining high-sensitivity cardiac troponin reference intervals.

The troponin 99th percentile is used as the laboratory decision point in the diagnosis of acute myocardial infarction. A recent publication has shown that the statistical treatment for outlier removal may dramatically change the calculated troponin 99th percentile. We have used our large database from the previously reported Canberra Heart Study to independently assess the effect of various methods for removing outliers on the calculated 99th percentile.

Harmonising Reference Intervals for Three Calculated Parameters used in Clinical Chemistry.

For more than a decade there has been a global effort to harmonise all phases of the testing process, with particular emphasis on the most frequently utilised measurands. In addition, it is recognised that calculated parameters derived from these measurands should also be a target for harmonisation. Using data from the Aussie Normals study we report reference intervals for three calculated parameters: serum osmolality, serum anion gap and albumin-adjusted serum calcium.

Cross-sectional study of high-sensitivity cardiac troponins T and I in a hospital and community outpatient setting.

Objectives: Cardiac troponins are specific for the heart, but not for the acute coronary syndrome. We wanted to assess how common elevated cardiac troponin concentrations were, in a population with significant non-cardiac disease.

Design & Methods: We measured both hs-cTnT and hs-cTnI on all samples submitted to the laboratory during one 24h period, and assessed the magnitude of the cTn concentration with the location and severity of disease of the patient.