Comparison of platelet function between sedentary individuals and competitive athletes at rest

BACKGROUND: There are controversial evidences on the effect of different types and workloads of physical exercise on primary hemostasis. In particular, little is known on the chronic influence of a strenuous and regular aerobic training regimen on platelet function. METHODS: The aim of this investigation was to compare platelet function between sedentary controls and trained athletes at rest and to evaluate whether a greater amount of exercise performed in professional cyclists may contribute to increased platelet chronic responsiveness compared to both elite cyclists and sedentary individuals. Platelet's ability to adhere and aggregate was assayed following a 12–24 h resting period in 49 active professional male road cyclists, 40 elite male cyclists and 43 matched sedentary healthy male volunteers, by the platelet function analyzer 100 (PFA-100). RESULTS AND DISCUSSION: Mean values of the collagen-epinephrine test did not differ between controls and athletes (sedentary controls: 111 ± 33 s; elite athletes: 113 ± 26 s, p = 0.93; professional athletes: 120 ± 33 s; p = 0.33), whereas mean values of the collagen-ADP test displayed a slightly but significant trend towards decreased values when comparing sedentary controls (83 ± 21 s) with either elite (77 ± 11 s, p < 0.01) or professional (75 ± 16 s, p < 0.01) athletes. CONCLUSION: The trend towards slightly lower collagen-ADP values are suggestive for a modest but significant chronic activation of primary hemostasis, highlighting the need to set appropriate reference ranges for the PFA-100 when evaluating primary hemostasis in physically active subjects

Non-commutability of results of highly sensitive troponin I and T immunoassays

Introduction: The measurement of cardiospecific troponins is pivotal in the diagnostic and prognostic approach of patients with suspected acute myocardial infarction (AMI). However, no information is available on the commutability of results between the novel highly-sensitive (HS) troponin T (TnT) and I (TnI) immunoassays. Materials and methods: The study population consisted in 47 consecutive patients presenting at the emergency department (ED) of the Academic Hospital of Parma with suspected AMI. TnI was measu-red with the novel prototype Beckman Coulter HS-AccuTnI immunoassay on Access 2, whereas TnT was measured with the Roche HS-TnT immunoassay on Cobas. Results: Eight out of the 47 patients (17%) were finally diagnosed as having an AMI. The overall cor-relation between TnT and TnI for total patient group was acceptable (r = 0.944; P < 0.01). Neverthe-less, when the analysis of data was carried out in separate groups according to the final diagnosis of AMI, two different equation results were obtained, i.e., HS-TnT = HS-AccuTnI x 0.349 + 20 (r = 0.823; P < 0.01) in non-AMI patients, and HS-TnT = HS-AccuTnI x 0.134 + 67 (r = 0.972; P < 0.01) in those with AMI. Conclusions: This study suggests the existence of two biological relationships between TnI and TnT in plasma, depending on the source of release from the myocardium. Moreover, the non-commutability of data between HS-TnT and HS-AccuTnI jeopardizes the clinical decision making, makes it impossible to calculate the delta or reference change value using the two biomarkers and to finally establish a reliable kinetics of troponin release from the injured myocardium

Blood sample quality using Greiner Bio-One HOLDEX\uae Single-Use Holder and VACUETTE\uae SAFELINK holder with male luer lock: a comparative study

Background: Hemolysis is the most frequent and potentially one of the most harmful causes of poor sample quality. Many strategies have been attempted for minimizing the risk of generating spurious hemolysis during blood collection, such as using the HOLDEX\uae single-use holder, which features a chamber that decelerates blood flow pressure before entering evacuated blood tubes. We have hence designed a study to establish whether the new VACUETTE\uae SAFELINK, which shares different structure but similar strategy affecting blood flow pressure, may ensure a comparable sample quality as using HOLDEX\uae single-use holder. Methods: A total number of 24 clinical chemistry, hematologic and hemostasis parameters were measured in paired blood samples collected from 30 healthy volunteers using either HOLDEX\uae single-use holder or VACUETTE\uae SAFELINK. Test results were compared with paired Student\u2019s t-test, Pearson\u2019s correlation and Bland-Altman plots. Results: All test results were non-significantly different in blood samples collected with HOLDEX\uae single-use holder or VACUETTE\uae SAFELINK except potassium, whose values were marginally higher in plasma collected with VACUETTE\uae SAFELINK. All Pearson\u2019s correlation coefficients were excellent except potassium, chloride and H-index. In this latter case, the correlation did not reach statistical significance. The percent bias of different parameters in samples collected with HOLDEX\uae single-use holder or VACUETTE\uae SAFELINK was minimal, comprised between 124.5% and +1.6%. In all cases the percent bias was comprised within the quality specifications tests. The rate of plasma samples with H-index &gt;3 was eventually lower when blood was collected using SAFELINK than with HOLDEX\uae single use holder (odds ratio, 0.52; 95% confidence interval, 0.17\u20131.60). Conclusions: The results of this comparative study suggest that sample quality is thoughtfully comparable using HOLDEX\uae single-use holder and VACUETTE\uae SAFELINK, thus translating into the concept that VACUETTE\uae SAFELINK may also be an effective means for reducing spurious hemolysis, especially when drawing blood from catheters

Analytical evaluation of Radiometer ABL90 FLEX PLUS enzymatic creatinine assay

Background: The diagnosis of kidney disease strongly relies on accurate and reproducible measurements of creatinine, even when performed with point of care testing (POCT) devices. Therefore, this study aimed at performing a comprehensive evaluation of the analytical performance of a creatinine enzymatic assay on the Radiometer ABL90 FLEX PLUS. Methods: This analytical evaluation encompassed the assessment of intra-assay, inter-assay and total imprecision, along with linearity on routine lithium-heparin plasma samples. Method comparison was also carried out using results generated with Radiometer ABL90 FLEX PLUS in heparinized whole blood and those obtained in paired heparinized plasma with a reference enzymatic creatinine assay and a Jaffe method, both assayed on Roche Cobas c702. Results: The intra-assay imprecision of Radiometer ABL90 FLEX PLUS creatinine enzymatic assay was between 0.33\u20131.26%, the inter-assay imprecision between 0.64\u20131.78%, thus yielding a total imprecision of 0.79\u20131.99%. The linearity of the assay was excellent (r=1.000; P&lt;0.001) in a range of plasma creatinine concentrations between 47 and 445 \ub5mol/L. An excellent correlation was found between creatinine measured on heparinized whole blood using Radiometer ABL90 FLEX PLUS enzymatic assay and plasma creatinine assayed on the same centrifuged samples using both Roche Cobas c702 creatinine enzymatic assay (r=0.99 and r=0.98; both P&lt;0.001). Compared to both Roche Cobas assays the percent bias was 641% and the agreement at chronic kidney disease (CKD) diagnostic thresholds was 6594%. Conclusions: The results of this analytical evaluation confirm that Radiometer ABL90 FLEX PLUS creatinine enzymatic assay is at least as suitable as a conventional clinical chemistry enzymatic technique for routine and urgent diagnosis of kidney diseases

Analytical validation of Gentian NGAL particle-enhanced enhanced turbidimetric immunoassay (PETIA)

Objectives: This study was designed to validate the analytical performance of the new Gentian particle-enhanced enhanced turbidimetric immunoassay (PETIA) for measuring neutrophil gelatinase-associated lipocalin (NGAL) in serum samples. Design and methods: Analytical validation of the Gentian NGAL assay was carried out on a Roche Cobas c501 and was based on assessment of limit of blank (LOB), limit of detection (LOD), functional sensitivity, imprecision, linearity and concordance with the BioPorto NGAL test. Results: The LOB and LOD of Gentian NGAL were found to be 3.8 ng/mL and 6.3 ng/mL, respectively. An analytical coefficient of variation (CV) of 20% corresponded to a NGAL value of 10 ng/mL. The intra-assay and inter-assay imprecision (CV) was between 0.4 and 5.2% and 0.6 and 7.1% and the total imprecision (CV) was 3.7%. The linearity was optimal at NGAL concentrations between 37 and 1420 ng/mL (r=1.00; p&lt;0.001). An excellent correlation was observed between values measured with Gentian NGAL and BioPorto NGAL in 74 routine serum samples (r=0.993). The mean percentage bias of the Gentian assay versus the Bioporto assay was +3.1% (95% CI, +1.6% to +4.5%). Conclusions: These results show that Gentian NGAL may be a viable option to other commercial immunoassays for both routine and urgent assessment of serum NGAL

Demographic, Clinical and Hematological Predictors of Carotid Atherosclerotic Plaque Histology

Aims: This retrospective observational study was aimed to identify hematological predictors of histological heterogeneity of carotid atherosclerotic plaques (CAPs). Results: The mean values of all demographic, clinical and haematological parameters did not differ between patients with or without symptomatic CAD. In univariate analysis, intraplaque hemorrhage was associated with male sex (r=0.18; p=0.032), superficial thrombosis with low hemoglobin (r=- 0.18; p=0.033), fibrosis with enhanced RDW (r=0.24; p=0.005), presence of foam cells with high WBC count (r=0.22; p=0.001), neovascularisation with high WBC count (r=0.17; p=0.048), whilst the presence of inflammatory infiltrate was also associated with high WBC count (r=0.17; p=0.043). Conlusions: The results of this retrospective observational study confirm that some traditional and inexpensive hematological parameters such as WBC count, hemoglobin and RDW may help identifying patients with more severe forms of CAD

Anti-SARS-CoV-2 Receptor-Binding Domain Total Antibodies Response in Seropositive and Seronegative Healthcare Workers Undergoing COVID-19 mRNA BNT162b2 Vaccination

Background: This study monitored total anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) RBD (receptor-binding domain) antibodies levels in a large population of healthcare workers undergoing mRNA COVID-19 vaccination. Methods. The study population consisted of employees of Pederzoli Hospital of Peschiera del Garda (Verona, Italy), who underwent voluntary vaccination with two doses of COVID-19 mRNA BNT162b2 (Comirnaty; Pfizer Inc). Venous blood was drawn immediately before the first vaccine dose, as well as 21 days (immediately before second vaccine dose) and 50 days afterwards. Humoral response was assessed with Roche Elecsys Anti-SARS-CoV-2 S total antibodies, on Roche Cobas 6000 (Roche Diagnostics). Results: The final study population consisted of 925 subjects (mean age, 44 \ub1 13 years; 457 women), 206 (22.3%) anti-SARS-CoV-2 baseline seropositive. The increase of total anti-SARS-CoV-2 RBD antibodies levels 21 days after the first vaccine dose was ~3 orders of magnitude higher in seropositive than in seronegative individuals (11782 vs. 42 U/mL; p &lt; 0.001). Total anti-SARS-CoV-2 RBD antibodies levels further increased by over 30-fold after the second vaccine dose in baseline seronegative subjects, while such increase was only ~1.3-fold in baseline seropositive subjects. In multivariate analysis, total anti-SARS-CoV-2 RBD antibodies level was inversely associated with age after both vaccine doses and male sex after the second vaccine dose in baseline seronegative subjects, while baseline antibodies value significantly predicted immune response after both vaccine doses in baseline seropositive recipients. Conclusion: Significant difference exists in post-mRNA COVID-19 vaccine immune response in baseline seronegative and seropositive subjects, which seems dependent on age and sex in seronegative subjects, as well as on baseline anti-SARS-CoV-2 antibodies level in seropositive patients

Urinary free cortisol assessment by liquid chromatography tandem mass spectrometry: a case study of ion suppression due to unacquainted administration of piperacillin

Introduction: Liquid chromatography coupled to atmospheric pressure ionization tandem mass spectrometry (LC-ESI-MS/MS) is currently considered the reference method for quantitative determination of urinary free cortisol (UFC). One of the major drawbacks of this measurement is a particular form of matrix effect, conventionally known as ion suppression. Materials and methods: We describe here the case of a 66-year-old-patient referred to the daily service of general medicine for intravenous antibiotic administration due to a generalized Staphylococcus aureus infection and for routine 24 hours UFC monitoring in the setting of glucocorticoid replacement therapy. Results: The observation of 10-fold decrease of internal standard of cortisol signal led us to hypothesize the presence of an ion suppression effect due to a co-eluting endogenous compound. Screening analysis of tandem mass spectrometry (MS/MS) spectra of the interfering molecule, along with in vitro confirmation analyses, were suggestive of the presence of high concentration of piperacillin. The problem was then easily solved with minor modifications of the chromatographic technique. Conclusions: According to our findings, antibiotic therapy with piperacillin/tazobactam should be regarded as an important interference in UFC assessment, which may potentially affect detection capability, precision and accuracy of this measurement. This case report emphasizes that accurate anamnesis and standardization of all phases of urine collection are essential aspects for preventing potential interference in laboratory testing. \ua9 Croatian Society of Medical Biochemistry and Laboratory Medicine

Patient posture for blood collection by venipuncture: recall for standardization after 28 years

Although data about the effect of posture on routine hematological testing were published 28 years ago, this pre-analytical issue has not been standardized so far. This study was planned to evaluate whether postural changes influence the results of hematology testing. METHODS: A complete blood count was performed in 19 healthy volunteers after 25min in the supine position, 20min in a sitting position and 20min stationary standing in an upright position. RESULTS: The change from supine to sitting position caused clinically significant increases in the hemoglobin, hematocrit and red blood cell count. Furthermore, the change from supine to standing caused clinically significant increases in the hemoglobin, hematocrit, red blood cell, leukocyte, neutrophil, lymphocyte, basophil and platelet counts, and mean platelet volume, and that from sitting to standing caused clinically significant increases in hemoglobin, hematocrit, and red blood cell, leukocyte, neutrophil and lymphocyte counts. CONCLUSION: The results of this investigation provide further support to the notion that effort should be made to achieve widespread standardization in the practice of phlebotomy, including patient posture. Copyright \ua9 2017 Associa\ue7\ue3o Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved