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It is now widely acknowledged that larger platelets are biologically more active and express a greater prothrombotic potential, but there is no definitive evidence on the diagnostic accuracy role of mean platelet volume (MPV) in patients with ischemic heart disease. We performed an electronic search for articles that have assessed the diagnostic accuracy of MPV in patients admitted at the emergency department with a suspected diagnosis of ischemic heart disease, including articles in which the exact number of true-positive, false-positive, false-negative and true-negative test results could be either directly or indirectly extracted. Heterogeneity was assessed by I(2) test. The cumulative estimates and 95% confidence interval (95% CI) of sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), area under the receiver operator characteristic (ROC) curve (AUC) and diagnostic odds ratio (DOR) were calculated using a random effect model. Three studies were finally included in our analysis (mean quality score, 10.8) totaling 3577 participants (566 cases and 3011 controls). The between-study variation was high (I(2), 96.2%; P < 0.001). The pooled estimates were 0.820 (95% CI 0.786-0.851) for sensitivity, 0.461 (95% CI 0.443-0.479) for specificity, 0.932 (95% CI 0.918-0.944) for NPV and 0.222 (95% CI 0.205-0.241) for PPV and 0.652 (95% CI 0.596-0.707) for AUC. The DOR was 3.9 (95% CI 2.3-6.5), with 0.52 diagnostic accuracy. The outcome of this meta-analysis suggests that MPV does not meet the requirements for efficient triage of patients in emergency department when used as stand-alone test, whereas its combination with high-sensitive troponin immunoassays merits further investigations.

Thrombolytic therapy by infusion of analogs of tissue plasminogen activator (tPA), other recombinant-based plasminogen activators (e.g., alteplase, reteplase, and tenecteplase), streptokinase, and urokinase (uPA) aims to clear blood clots and restore blood flow in occluded blood vessels. Thrombolytic therapy is thereby frequently used in patients with myocardial infarction, stroke, peripheral arterial disease, and massive pulmonary embolism. The leading drawbacks of thrombolysis and associated therapy are represented by a significant burden of inefficacy combined with a high risk of bleeding complications. Recent advances in understanding the complex pathophysiology of vascular occlusions, combined with important technological innovations, are notably improving the therapeutic armamentarium against thrombotic and occlusive disorders. Most of the past and ongoing research in this area have entailed thrombus-targeted fibrinolytic therapy with either tissue- and fibrin-specific immunoconjugates, fibrinolytic-bearing erythrocytes, or fibrinolytic-bearing nanoparticles. The greatest advantages of thrombus-targeted fibrinolysis, especially with biocompatible nanoparticles, are represented by their preferential localization within developing clots, effectual thrombolysis and enhanced safety due to substantial reduction of the dosage of fibrinolytic agents, and reduced onstream adverse effects. These positive biological features, coupled with minimal extravasation and favorable clearance from the circulation, appear advantageous for obtaining more efficacious and durable thrombolytic effects while concomitantly lowering or even eliminating the risk of systemic bleeding complications that typically accompany the injection of free or soluble plasminogen activators. Although an ideal technique has not been definitely established so far, tPA-bearing nanoparticles exhibiting affinity for clot-specific cells and biomolecules coupled with low-frequency ultrasound seem to bear the greatest advantages for prevention and therapy of acute thrombosis, with the possibility to specifically guide and concentrate the thrombolytic agent at the site of pathologic thrombi and clear preexisting clots by a series of mechanisms combining mechanical stress and increased penetration and effectiveness of the drugs employed., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

An early diagnosis is crucial for effective triage and management of patients with suspected acute myocardial infarction (AMI). Although troponin testing is the cornerstone of diagnosis, the sensitivity of this biomarker is still suboptimal at patient admission. The heart-type fatty acid binding protein (H-FABP) is an early and sensitive biomarker of myocardial ischemia, whose appropriate setting is in combination with troponin testing. We performed a systematic review and meta-analysis of articles that have assessed the combination of troponin and H-FABP in the early diagnosis of AMI. Eight studies, totaling 2735 patients, met the inclusion criteria but none of them used a high-sensitivity troponin immunoassay. The between-study variation was high (98.5%), and attributable to heterogeneity. When considered alone, troponin exhibited a significantly greater pooled area under the curve (AUC) than H-FABP alone (0.820 versus 0.784; p<0.001). The pooled specificity was also higher for troponin alone than for H-FABP alone (0.94 versus 0.83; p<0.001), whereas the cumulative sensitivity was lower for troponin than for H-FABP (0.73 versus 0.80; p=0.02). The combination of both biomarkers exhibited a greater AUC than troponin alone (0.881; p<0.001), as well as a higher pooled sensitivity (0.91; p<0.001), which was however counterbalanced by a lower specificity (0.82; p<0.001). These results attest that the combination of H-FABP with a conventional troponin immunoassay seems advantageous for increasing the sensitivity of the former biomarker, at the expense of a lower specificity. The introduction of H-FABP testing would hence require careful assessment of laboratory data or clinical signs and symptoms for excluding sources of elevation different from AMI. Further studies are needed to assess the diagnostic effectiveness of combining H-FABP with a high-sensitivity troponin immunoassay., (Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Background: A number of preanalytical activities strongly influence sample quality, especially those related to sample collection. Since blood drawing through intravenous catheters is reported as a potential source of erythrocyte injury, we performed a critical review and meta-analysis about the risk of catheter-related hemolysis., Materials and Methods: We performed a systematic search on PubMed, Web of Science and Scopus to estimate the risk of spurious hemolysis in blood samples collected from intravenous catheters. A meta-analysis with calculation of Odds ratio (OR) and Relative risk (RR) along with 95% Confidence interval (95% CI) was carried out using random effect mode., Results: Fifteen articles including 17 studies were finally selected. The total number of patients was 14,796 in 13 studies assessing catheter and evacuated tubes versus straight needle and evacuated tubes, and 1251 in 4 studies assessing catheter and evacuated tubes versus catheter and manual aspiration. A significant risk of hemolysis was found in studies assessing catheter and evacuated tubes versus straight needle and evacuated tubes (random effect OR 3.4; 95% CI = 2.9-3.9 and random effect RR 1.07; 95% CI = 1.06-1.08), as well as in studies assessing catheter and evacuated tubes versus catheter and manual aspiration of blood (OR 3.7; 95% CI = 2.7-5.1 and RR 1.32; 95% CI = 1.24-1.40)., Conclusions: Sample collection through intravenous catheters is associated with significant higher risk of spurious hemolysis as compared with standard blood drawn by straight needle, and this risk is further amplified when intravenous catheter are associated with primary evacuated blood tubes as compared with manual aspiration.

Background: Early diagnosis is crucial for management of patients with suspected acute myocardial infarction (AMI). Among innovative and promising biomarkers, the recent interest raised on glycogen phosphorylase isoenzyme BB (GPBB) has prompted us to perform a meta-analysis of published studies., Materials and Methods: A systematic electronic search was carried out on PubMed, Web of Science and Google Scholar, with no date restriction, to retrieve all articles that have investigated the early diagnostic performance of GPBB in patients with suspected AMI, and directly reported or allowed calculation of sensitivity and specificity. A meta-analysis of the reported sensitivity and specificity of each study and pooled area under the curve (AUC) was then performed by random effect approach. Heterogeneity was assessed by I-square statistics., Results: Eight studies were finally selected for analysis (941 subjects; 506 cases and 435 controls), with a high heterogeneity (I-squared, 86.3%). The resulting pooled estimates and 95% confidence interval were 0.854 (0.801-0.891) for sensitivity, 0.767 (0.713-0.815) for specificity, 0.826 (0.774-0.870) for negative predictive value, 0.802 (0.754-0.844) for positive predictive value, and 0.754 (9.602-0.907) for AUC. In those studies that have simultaneously assessed GPBB and a troponin immunoassay, the combination of these biomarkers did not significantly improve the performance of troponin alone., Conclusion: GPBB does not meet the current requirements for an efficient diagnosis of AMI when used as a stand-alone test, whereas its combination with troponin merits further investigation in larger trials.

Laboratory diagnostics, a pivotal part of clinical decision making, is no safer than other areas of healthcare, with most errors occurring in the manually intensive preanalytical process. Patient misidentification errors are potentially associated with the worst clinical outcome due to the potential for misdiagnosis and inappropriate therapy. While it is misleadingly assumed that identification errors occur at a low frequency in clinical laboratories, misidentification of general laboratory specimens is around 1% and can produce serious harm to patients, when not promptly detected. This article focuses on this challenging issue, providing an overview on the prevalence and leading causes of identification errors, analyzing the potential adverse consequences, and providing tentative guidelines for detection and prevention based on direct-positive identification, the use of information technology for data entry, automated systems for patient identification and specimen labeling, two or more identifiers during sample collection and delta check technology to identify significant variance of results from historical values. Once misidentification is detected, rejection and recollection is the most suitable approach to manage the specimen.

Remarkable advances in instrument technology, automation and computer science have greatly simplified many aspects of previously tedious tasks in laboratory diagnostics, creating a greater volume of routine work, and significantly improving the quality of results of laboratory testing. Following the development and successful implementation of high-quality analytical standards, analytical errors are no longer the main factor influencing the reliability and clinical utilization of laboratory diagnostics. Therefore, additional sources of variation in the entire laboratory testing process should become the focus for further and necessary quality improvements. Errors occurring within the extra-analytical phases are still the prevailing source of concern. Accordingly, lack of standardized procedures for sample collection, including patient preparation, specimen acquisition, handling and storage, account for up to 93% of the errors currently encountered within the entire diagnostic process. The profound awareness that complete elimination of laboratory testing errors is unrealistic, especially those relating to extra-analytical phases that are harder to control, highlights the importance of good laboratory practice and compliance with the new accreditation standards, which encompass the adoption of suitable strategies for error prevention, tracking and reduction, including process redesign, the use of extra-analytical specifications and improved communication among caregivers.

Owing to a widespread diffusion, the consumption of banned and potentially harmful substances in sports has become a problem for the public health. Current estimations of the prevalence of doping in sports are rather uncertain, as most investigative tools do not reflect an absolute statistical power. However, the emerging scenario reflects a concerning underestimation by Structures and Institutions that should establish definitive rules and set reliable controls. Owing to restricted resources, prevention and fight against doping must be supported by meditated and rational strategies, with the aim to identify suitable contests and accurate procedures, considering carefully ethical issues that may arise from the positivity of the athletes to antidoping controls.