Serum 99th centile values for two heart-type fatty acid binding protein assays.
ABSTRACT We have previously demonstrated that heart-type fatty acid binding protein (H-FABP) is an independent prognostic marker for survival after acute coronary syndrome (ACS). This study aimed to define the 99th centile values for H-FABP as determined with two different assays, and to study the relationship with age, gender and renal function.
H-FABP was measured on redundant routine outpatient samples using the MARKIT-M (Dainippon) and the Evidence Investigator (Randox) assays.
Two hundred and forty-two subjects with Siemens Ultra-TnI value <0.045 microg/L (99th centile) were studied. In all, 174 subjects had estimated glomerular filtration rate (eGFR) >60 mL/min. The 99th centile values for subjects with eGFR >60 mL/min for the Evidence Investigator H-FABP were 5.3 and 5.8 microg/L and for the MARKIT-M H-FABP were 8.3 and 9.1 microg/L in female and male subjects, respectively. There is an increase in H-FABP with age in subjects with normal renal function for both assays. Gender comparison showed no significant difference for either assay. Comparison of samples showed that subjects with eGFR <60 mL/min showed a median increase of 0.71 microg/L with Evidence Investigator assay and 1.09 microg/L with MARKIT-M assay compared with subjects with eGFR >60 mL/min. Calibration differences were confirmed by cross measurement of calibrators and recombinant H-FABP.
We have defined the 99th centile values for H-FABP in a population of primary and secondary care outpatients that can be used to risk stratify patients with ACS. We have confirmed that H-FABP increases with renal dysfunction and age, but have not confirmed the gender difference previously reported.
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ABSTRACT: Chest pain is one of the most frequent reasons for presentation to the emergency department (ED), although the estimated prevalence of AMI (acute myocardial infarction) in the ED is about 4%. One criterion for diagnosis of AMI is the demonstration of a rise and/or fall in cardiac troponins, but time is needed for this to happen. Thus, the use of an additional 'early marker' of cardiac injury may aid to exclude AMI rapidly. The aim of the study was to evaluate the possibility of excluding AMI with the determination of heart-type fatty acid-binding protein (H-FABP) on baseline samples of patients referring to the ED for chest pain. 26 AMI patients and 41 non-AMI comparisons were included in the study. Both H-FABP and high sensitivity cardiac troponin T (hs-cTnT) were measured in baseline samples from these subjects. H-FABP had a negative predictive value of 100%, thus indicating the possibility of its usage in a rule-out strategy for AMI in ED for patients presenting with chest pain.Acute Cardiac Care 11/2013;
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ABSTRACT: Background. Heart-type fatty acid-binding protein (H-FABP) is a low molecular weight protein involved in the intracellular uptake and buffering of long chain fatty acids in the myocardium. It is an early marker for ACS. We have evaluated the Randox Laboratories immunoturbidimetric assay on a Siemens Advia 1800 analyzer. The assay employs latex particles coated with mouse monoclonal anti-HFABP antibodies to generate turbidity. Methods. We used redundant patient samples and pools to assess precision, functional sensitivity, limit of detection, linearity, recovery of recombinant H-FABP and interference. We evaluated the 99th centile values and compared H-FABP with troponin in samples routinely received from chest pain patient samples. Results. Precision was typically < 10% and 12.5% at all concentrations for within and between batches. The functional sensitivity was 2.4 μg/L. The assay was linear on dilution over the range 2.76-115 μg/L. Recovery of recombinant H-FABP was approximately 20-25%. No interference was seen with haemoglobin concentrations <1.5 g/L, bilirubin < 250 μg/L and triacylglycerol < 5 mmol/L or rheumatoid factor. The 99th centile value in a reference population with eGFR > 60mL/min/1.73m(2) was 9.1 μg/L with no significant gender difference. H-FABP was measured in routine clinical samples (N = 1310) received for troponin I measurement. Using Siemens TnI > 50 ng/L as an indicator of myocardial damage, the ROC area under curve for H-FABP was 0.82. Conclusions. The immunoturbidimetric H-FABP assay is robustly designed and shows good analytical performance. It is therefore well suited for use in a routine clinical laboratory.Scandinavian journal of clinical and laboratory investigation 11/2012; · 1.38 Impact Factor