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Sticky platelet syndrome (SPS) is a disorder with familial occurrence and autosomal dominant trait characterized by platelet hyperaggregability in response to a low concentration of adenosine diphosphate (ADP) and/or epinephrine (EPI). The etiology of SPS may be associated with platelet microRNAs (miRNAs), which are considered as potential biomarkers of platelet function and antiplatelet therapy. We were monitoring the expression of platelet miRNAs in patients with laboratory diagnosed SPS and healthy controls. We have found a statistically significant increased expression of both miR-423-5p and miR-338-3p as well as a statistically significant decreased expression of miR-425-5p between the group of patients with diagnosed SPS type II and the group of healthy controls, which seems to be an interesting issue for a further research.

Venous thromboembolism (VTE) represents one of the leading causes of death during pregnancy. The greatest risk for it is the presence of medical or family history of VTE, stillbirth, cesarean section and selected thrombophilia. Appropriate thromboprophylaxis has the potential to decrease the risk of VTE in at-risk pregnant patients by 60–70%. Based on this, the authors reviewed the PubMed, Web of Science and Scopus databases to identify the possibilities of thromboprophylaxis in pregnant patients with a high risk of VTE. Moreover, they summarized its management in specific situations, such as cesarean delivery or neuraxial blockade. Currently, low-molecular-weight heparins (LMWH) are the preferred drugs for anticoagulant thromboprophylaxis in the course of pregnancy and postpartum due to easy administration and a lower rate of adverse events. [ABSTRACT FROM AUTHOR]

The availability of direct oral anticoagulants has caused a paradigm shift in the management of thrombosis. Rivaroxaban and apixaban are 2 direct oral anticoagulants whose target specificity is activated factor X (FXa). However, it is still not fully understood if and how xabans impact platelet function. This observational study aimed to assess the in vitro platelet function in patients with atrial fibrillation receiving xabans. This was a single-center study quantifying platelet aggregation in 41 patients treated with apixaban or rivaroxaban by light transmission aggregometry. The thrombin receptor activating peptide (TRAP)-induced platelet aggregation was significantly lower 2 hours after taking rivaroxaban or apixaban compared to baseline value (56.15% [8.53%] vs 29.51% [12.9%]; P = .000). Moreover, concomitant use of angiotensin-converting enzyme blockers, proton pump inhibitors, and statins reduces the efficiency of xabans. The TRAP-induced platelet aggregation was reduced in patients with cardiovascular disease 2 hours after receiving xabans. [ABSTRACT FROM AUTHOR]

The availability of direct oral anticoagulants has caused a paradigm shift in thrombosis management. The direct thrombin inhibitor dabigatran seems to obstruct tenase complex by inhibiting thrombin generated in the initial phase and feed back to the amplification phase of cell-based coagulation reactions. However, it is still not fully understood if and how dabigatran impact platelet function. This observational study aimed to assess in vitro platelet function in patients with atrial fibrillation receiving dabigatran. Platelet aggregability was tested with platelet-rich plasma using platelet aggregometry (PACKS-4 aggregometer). Blood samples were stimulated with thrombin receptor agonist peptide (TRAP; 32μmmol/L). Results: A total of 28 patients with nonvalvular atrial fibrillation were enrolled. The mean age was 71.57 (9.75) years (range: 50-87 years), 16 patients were women, and the mean CHA2DS2VASc score was 3.93 (1.41). All patients began treatment with dabigatran as initial anticoagulant treatment. The minimum term use of dabigatran was 18 days. Dabigatran doses were 110 mg (57.14%) or 150 mg (42.86%) twice daily. The TRAPinduced platelet aggregation was significantly lower 2 hours after taking dabigatran compared to baseline value (79.39 [13.38] vs 90.14 [10.5]). Conclusion: The TRAP-induced platelet aggregation was reduced in cardiovascular patients 2 hours after receiving dabigatran. Our findings could have some important clinical implications because platelet aggregation and coagulation cascade are affected at the same time. [ABSTRACT FROM AUTHOR]

Disequilibrium of hemostasis is central to the pathogenesis of all thromboses, and platelets are essential for primary hemostasis. The platelet membrane glycoprotein receptor is involved in the clot formation in blood; therefore, the changes in related genes could impair platelet aggregation in patients with sticky platelet syndrome (SPS). Patients with SPS who experienced fetal loss were shown to harbor a risk haplotype at GP6 locus. The aim of the study was to examine the genetic linkage of this selected risk haplotype with single nucleotide variations (SNVs) in the coding sequence of the GP6 gene in order to identify possible functional SNVs in association with SPS and fetal loss. A total of 37 patients with SPS manifested fetal loss, and 42 healthy controls were enrolled in the study. The SPS was diagnosed with platelet aggregometry. The SNVs were determined by dideoxy sequencing and high-resolution melting analysis. The missense variations were detected in patients with risk haplotype only. The association analysis showed association of the minor alleles with the SPS manifested by fetal loss as follows—rs1671152 (odds ratio [OR]: 4.667, 95% confidence interval [CI]: 1.462-14.89, P = .006), rs2304167 (OR: 5.085, 95% CI: 1.605-16.10, P = .003), and rs1654416 (OR: 5.085, 95% CI: 1.605-16.10, P = .003). Using the Expectation-Maximization (EM) algorithm, the estimated minor haplotype with predicted protein residue PEAN was significantly associated with the given phenotype (OR: 4.746, 95% CI: 1.486-15.15, P = .005). We have shown that haplotype PEAN associated with SPS and manifested by fetal loss and suggest that the mechanism involved in the action of GPVI has significant effect on GPVI-mediated signal transduction through Syk-phosphorylation. [ABSTRACT FROM AUTHOR]

Congenital fibrinogen disorders are caused by mutations in one of the three fibrinogen genes that affect the synthesis, assembly, intracellular processing, stability or secretion of fibrinogen. Functional studies of mutant Bβ-chains revealed the importance of individual residues as well as three-dimensional structures for fibrinogen assembly and secretion. This study describes two novel homozygous fibrinogen Bβ chain mutations in two Slovak families with afibrinogenemia and hypofibrinogenemia. Peripheral blood samples were collected from all subjects with the aim of identifying the causative mutation. Coagulation-related tests and rotational thromboelastometry were performed. All exons and exon-intron boundaries of the fibrinogen genes (FGA, FGB and FGG) were amplified by PCR followed by direct sequencing. Sequence analysis of the three fibrinogen genes allowed us to identify two novel homozygous mutations in the FGB gene. A novel Bβ chain truncation (BβGln180Stop) was detected in a 28-year-old afibrinogenemic man with bleeding episodes including repeated haemorrhaging into muscles, joints, and soft tissues, and mucocutaneous bleeding and a novel Bβ missense mutation (BβTyr368His) was found in a 62-year-old hypofibrinogenemic man with recurrent deep and superficial venous thromboses of the lower extremities. The novel missense mutation was confirmed by molecular modelling. Both studying the molecular anomalies and the modelling of fibrinogenic mutants help us to understand the extremely complex machinery of fibrinogen biosynthesis and finally better assess its correlation with the patient's clinical course. [ABSTRACT FROM AUTHOR]

Patient: Female, 51., Final Diagnosis: Sticky platelets syndrome., Symptoms: Pulmonary embolism., Medication: -, Clinical Procedure: Thrombolysis., Specialty: Hematology., Objective: Disease of unknown ethiology., Background: Sticky platelets syndrome (SPS) is an inherited thrombophilia characterized by platelet hyperaggregability, which can lead to the higher risk of thrombosis. The etiology of SPS remains unclear, but several gene polymorphisms have been recently studied and autosomal dominant heredity is suspected. Although SPS is traditionally connected with arterial thrombosis, several cases of SPS as a cause of venous thromboembolism have been described., Case Report: We report the case of a 51-year-old apparently healthy woman with massive pulmonary embolism, who required thrombolytic therapy. In this patient SPS was identified as the only condition leading to higher risk of developing thromboembolic disease., Conclusions: Although at present few physicians have practical experience with SPS, this syndrome may lead to serious health problems or even death. The presented case points to the benefit of SPS diagnostics in standard screening of inherited thrombophilia for effective prophylaxis and treatment in patients with venous thromboembolism.