A Functional Assay for the Determination of Heparin-Induced Thrombocytopenia via Flow Cytometry

Heparin-induced thrombocytopenia (HIT) is a life-threatening complication of heparin therapy (both unfractionated heparin and low-molecular-weight heparin). In our study, we examined a group of 122 patients with suspected HIT. The samples of all patients were analyzed in the first step using an immunoassay (ID-PaGIA Heparin/PF4, Hemos1L-Acustar HIT IgG, ZYMUTEST HIA Monostrip IgG) to detect the presence of antibodies against heparin-PF4 complexes (platelet factor 4). When the immunoassay was positive, the sample was subsequently analyzed for HIT with a functional flow cytometry assay, the HITAlert kit, the purpose of which was to demonstrate the ability of the antibodies present to activate platelets. A diagnosis of HIT can be made only after a positive functional test result. In this article, we present an overview of our practical experience with the use of the new functional method of analysis, HIT, with flow cytometry. In this work, we compared the mutual sensitivity of two functional tests, SRA and the flow cytometry HITAlert kit, in patients perceived as being at risk for HIT. This work aims to delineate the principle, procedure, advantages, pitfalls, and possibilities of the application of the functional test HITAlert using flow cytometry.

MiR-126 and miR-146a as markers of type 2 diabetes mellitus: a pilot study

INTRODUCTION

Despite known risk factors for developing type 2 diabetes mellitus (T2D), the research community still tries to discover new markers that would widen our diagnostic and therapeutic approach to diabetes. Therefore, research on microRNA (miR) in diabetes thrives. This study aimed to assess the utility of miR-126, miR-146a, and miR-375 as novel diagnostic markers for T2D.

METHODS

We examined relative quantities of miR-126, miR-146a, and miR-375 in the serum of patients with established type 2 diabetes mellitus (n = 68) and compared these with a control group (n = 29). We also undertook a ROC analysis of significantly changed miR to examine their use as a diagnostic test.

RESULTS

MiR-126 (p < 0.0001) and miR-146a (p = 0.0005) showed a statistically significant reduction in patients with type 2 diabetes mellitus. MiR-126 also proved to be an exceptional diagnostic test in our study cohort, with high sensitivity (91 %) and specificity (97 %). We did not find any difference in our study groups' relative quantities of miR-375.

CONCLUSION

The study proved a statistically significant reduction of miR-126 and miR-146a in patients with T2D (Tab. 4, Fig. 6, Ref. 51). Text in PDF www.elis.sk Keywords: microRNA, epigenetics, genomics, type 2 diabetes mellitus, miR-126, miR-146a and miR-375.

How can Secondary Thromboprophylaxis in High-Risk Pregnant Patients be Improved?

Low-molecular-weight heparin (LMWH) is suggested for thromboprophylaxis in pregnant women with previous venous thromboembolism (VTE). Anyway, there is only limited amount of studies evaluating the effect of LMWH on hemostatic parameters during pregnancy of patients with previous VTE and the need of secondary thromboprophylaxis. We therefore provide results of prospective and longitudinal assessment of changes in hemostasis in high-risk pregnant women at four times during pregnancy (T1–T4) and one time after the postpartum period (T5) used for individualized modification of thromboprophylaxis. In this study, the results of coagulation factor VIII (FVIII) and protein S (PS) activity, ProC Global ratio and anti-Xa activity were evaluated. Despite the thromboprophylaxis, an increased predisposition to thromboembolic complications was detected (significant increase in FVIII activity and decrease in PS function, ProC Global ratio not normalized even after the postpartum period – p < .0001 between controls and T5 for PS and ProC Global). These results indicate that hemostasis may not be restored even 6 to 8 weeks after delivery and pose the question when is it safe to withdraw the anticoagulant thromboprophylaxis in high-risk patients with prior VTE.

Cancer-associated thrombosis - treatment and prevention with direct oral factor Xa inhibitors

BACKGROUND

Venous thromboembolism (VTE) is a frequent cause of morbidity and mortality in patients with cancer. Moreover, management of VTE is frequently connected with complications, namely risk of recurrent VTE and bleeding. Low molecular weight heparins (LMWH) therapy administrated for 3-6 months is currently considered a standard for the treatment of cancer-associated VTE (CA-VTE). Direct oral factor Xa inhibitors (FXaI) apixaban, edoxaban and rivaroxaban have emerged as a new possibility for long-term antithrombotic therapy for VTE. These agents expose several advantages in individuals with cancer, and might overcome several disadvantages connected with LMWH therapy.

PURPOSE

First clinical studies with oral FXaI for the treatment of CA-VTE with very promising results were recently published. The article summarizes current data regarding the use of oral FXaI in the treatment of CA-VTE.

Use of Fibrinogen Determination Methods in Differential Diagnosis of Hypofibrinogenemia and Dysfibrinogenemia

BACKGROUND

Fibrinogen plays an important role in hemostasis. The normal concentration of fibrinogen in blood plasma is between 1.8 - 4.2 g/L. Decreased fibrinogen levels are observed in congenital afibrinogenemia, hypofibrinogenemia, dysfibrinogenemia, disseminated intravascular coagulation, fibrinolytic therapy, some more severe hepatic parenchymal disorders, and increased blood loss. Elevated fibrinogen levels occur in inflammatory diseases and neoplastic diseases, in pregnancy, and postoperative conditions. Functional fibrinogen measurement is also one of the basic coagulation screening tests. The fibrinogen antigen assay is used to distinguish between qualitative and quantitative fibrinogen disorders.

METHODS

The aim of the study was the use of fibrinogen determination methods in differential diagnosis of hypofibrinogenemia and dysfibrinogenemia, statistical evaluation and determine the relationship of fibrinogen Clauss assay, prothrombin time (PT) derived fibrinogen assay, and fibrinogen antigen in the group of 60 patients with congenital fibrinogen disorders (n = 40 dysfibrinogenemia; n = 20 hypofibrinogenemia).

RESULTS

The results measured by the PT-derived fibrinogen assay were approximately four times higher compared to the fibrinogen Clauss assay in the group of patients with dysfibrinogenemia. In patients with hypofibrinogenemia, there is a correlation (r = 0.9016) between the fibrinogen Clauss assay and PT-derived fibrinogen assay with a statistical significance of p < 0.0001. Using a linear or quadratic interpolation function, we were able to determine the fibrinogen Clauss assay and the fibrinogen antigen assay before analysis.

CONCLUSIONS

The higher level of the PT-derived fibrinogen assay compared to the fibrinogen Clauss assay in the group of patients with dysfibrinogenemia may pose a greater risk to asymptomatic patients who require diagnosis and treatment in case of bleeding. The fibrinogen value using the PT-derived fibrinogen assay could erroneously give a normal level. The use of the interpolation function is important to estimate the value of fibrinogen activity and antigen before the analysis itself by the Clauss assay or analysis by the fibrinogen antigen assay.

How Can Rotational Thromboelastometry as a Point-of-Care Method Be Useful for the Management of Secondary Thromboprophylaxis in High-Risk Pregnant Patients?

Thromboprophylaxis with low-molecular-weight heparin (LMWH) for patients with a history of venous thromboembolism (VTE) is suggested. Rotational thromboelastometry (ROTEM^®) represents an innovative point-of-care method enabling the complex and quick evaluation of hemostasis. However, there are only episodic cases of its use for hemostasis assessment and guidance of LMWH in pregnancy. Therefore, we provide the results of unique prospective and longitudinal monitoring of hemostasis in high-risk pregnant women, which we used for the individualized optimalization of secondary thromboprophylaxis. According to the shortening of clot formation time (CFT) in EXTEM (p = 0.0007 from the 26th gestational week vs. controls) and INTEM (p = 0.002 from the 35th gestational week), increase in alpha angle (AA) in EXTEM, INTEM, and HEPTEM, and the persistence of increase in maximum clot firmness (MCF) in EXTEM, INTEM, and HEPTEM (p < 0.001 from the 26th and 35th gestational week vs. controls for EXTEM and INTEM, p = 0.0012 from the 26th gestational week in HEPTEM), LMWH dose was modified. Even after the postpartum period, AA in EXTEM was steeper than in controls (p = 0.0007), indicating that hemostasis is not fully normalized after 6–8 weeks following delivery. Therefore, ROTEM may be a useful tool for the individual evaluation of the termination of anticoagulant thromboprophylaxis.

NMR plasma metabolomics study of patients overcoming acute myocardial infarction: in the first 12 h after onset of chest pain with statistical discrimination towards metabolomic biomarkers

Acute myocardial infarction (AMI) is one of the leading causes of death among adults in older age. Understanding mechanisms how organism responds to ischemia is essential for the ischemic patient's prevention and treatment. Despite the great prevalence and incidence only a small number of studies utilize a metabolomic approach to describe AMI condition. Recent studies have shown the impact of metabolites on epigenetic changes, in these studies plasma metabolites were related to neurological outcome of the patients making metabolomic studies increasingly interesting. The aim of this study was to describe metabolomic response of an organism to ischemic stress through the changes in energetic metabolites and aminoacids in blood plasma in patients overcoming acute myocardial infarction. Blood plasma from patients in the first 12 h after onset of chest pain was collected and compared with volunteers without any history of ischemic diseases via NMR spectroscopy. Lowered plasma levels of pyruvate, alanine, glutamine and neurotransmitter precursors tyrosine and tryptophan were found. Further, we observed increased plasma levels of 3-hydroxybutyrate and acetoacetate in balance with decreased level of lipoproteins fraction, suggesting the ongoing ketonic state of an organism. Discriminatory analysis showed very promising performance where compounds: lipoproteins, alanine, pyruvate, glutamine, tryptophan and 3-hydroxybutyrate were of the highest discriminatory power with feasibility of successful statistical discrimination.