Antiphospholipid syndrome (APS) is a hypercoagulation condition associated with the incidence of heterogenic antiphospholipid antibodies (aPLs), which non-specifically affect hemostasis processes. APS is clinically manifested by recurrent arterial and venous thromboses and reproduction losses. The aPL antibodies, which may induce clinical manifestations of APS, include criteria antibodies anti-cardiolipin, anti-β2-glycoprotein-I, and lupus anticoagulant, but also non-criteria antibodies, for example anti-β2-glycoprotein-I domain I, anti-phosphatidylserine/prothrombin, anti-annexin V, and many others. APS occurs mostly in patients of younger and middle age, most frequently in females. Laboratory diagnostics of APS are quite difficult, as they include a wide spectrum of examining methods, which are based on various principles of detection and are performed using various laboratory techniques. The objective of the review is to describe the current state of potentially examined biomarkers and methods in APS diagnostics. The aforementioned biomarkers are lupus anticoagulant, anti-β2-glycoprotein-I, anti-cardiolipin, anti-β2-glycoprotein-I domain I, anti-phosphatidylserine/prothrombin, anti-β2-glycoprotein-I IgA, anti-cardiolipin IgA, anti-annexin V and II, anti-prothrombin, anti-cardiolipin/vimentin, anti-protein S/protein C, and antibodies against phospholipid antigens for whose diagnostics we may use some of the methods established for a long time and some of the modern methods—the coagulation method for the determination of lupus anticoagulant (LA), enzyme-linked imunosorbent assay (ELISA), chemiluminescence analysis (CLIA), multiplex fluorescence flow immunoassay (MFFIA), fluorescence enzyme immunoassay (EliA), line immunoassay (LIA), multiline dot assay (MLDA), and thin-layer chromatography (TLC). Conclusion: Antibodies against phosphatidylethanolamine, phosphatidic acid, phosphatidylserine, phosphatidylinositol, cardiolipin/vimentin complex, and annexin V are currently the most studied new markers. However, these assays have not been standardized until now, both from the laboratory and clinical point of view. In this review we summarize the evidence of the most studied aPL markers and their potential clinical significance in seronegative APS (SN-APS).

The studied group comprises 124 patients with acute myocardial infarction on dual antiplatelet therapy with acetylsalicylic acid (ASA) and thienopyridines. Antiplatelet therapy was monitored by platelet-rich plasma light transmittance aggregometry (LTA) using the APACT 4004 analyzer (Helena Laboratories) and by whole blood impedance aggregometry (multiple electrode aggregometry [MEA]) using the Multiplate analyzer (Dynabyte). Platelet aggregation was detected after stimulation with arachidonic acid for detection of aspirin resistance and with adenosine diphosphate (ADP) and prostaglandin E1 for detection of thienopyridine resistance. To determine the frequencies of P2Y12 (i-744T>C; rs2046934), P2Y12 (34C>T; rs6785930), COX-1 (-842A>G; rs10306114), GPVI (13254T>C; rs1613662), and GPIbA (5T>C; rs2243093) polymorphisms, DNA of patients with AIM was tested by real-time-polymerase chain reaction and melting curve analysis using the LightCycler 480 analyzer (Roche Diagnostics). The cut-off points used for patients with effective ASA therapy are 25% of aggregated platelets and 220 area under the curve (AUC)/min if LTA or MEA, respectively. The cut-off points used for effective thienopyridine therapy are 45% of aggregated platelets or 298 AUC/min, respectively. Both LTA and MEA found that aspirin and thienopyridine therapies failed in 14.51% and 25.8%, respectively. The data were statistically processed using the SPSS version 15 software (SPSS, Inc.). Associations between receptor mutation status and response to therapy were assessed with Fisher's exact test. The significance level was set at 0.05. The aim of our work was to use the two functional laboratory methods described earlier to assess both aspirin and thienopyridine resistance and to determine the contribution of genetic polymorphisms of platelet receptors to resistance to antiplatelet therapy in AIM. Fisher's exact test showed a significant statistical correlation between platelet function tests suitable for monitoring ASA resistance, that is, LTA and MEA, and mutation status of COX1_A1 (-A842G). Fisher's exact test showed no statistically significant correlations between platelet function tests suitable for monitoring ASA resistance, that is, LTA and MEA, and mutation status of GP1bA (-5T>C) and GP6 (T13254C). Fisher's exact test showed no statistically significant correlation between mutational statuses of the receptors P2RY12 (i-T744C), P2RY12 (C34T), GP1bA (-5T>C), or GP6 (T13254C) and response to antiplatelet therapy with 75 mg of clopidogrel.

Aim: The aim of this study was to assess coagulation markers of endothelial damage and examine new markers of endothelial activation such as matrix metalloproteinases (MMPs) in a group of healthy pregnant women. Matrix metalloproteinase (MMP)-...

The deficiency of natural anticoagulants—antithrombin (AT), protein C (PC), and protein S (PS)—is a highly predisposing factor for thrombosis, which is still underdiagnosed at the genetic level. We aimed to establish and evaluate an optimal diagnostic approach based on a high-throughput sequencing platform suitable for testing a small number of genes. A fast, flexible, and efficient method involving automated amplicon library preparation and target sequencing on the Ion Torrent platform was optimized. The cohort consisted of a group of 31 unrelated patients selected for sequencing due to repeatedly low levels of one of the anticoagulant proteins (11 AT-deficient, 13 PC-deficient, and 7 PS-deficient patients). The overall mutation detection rate was 67.7%, highest in PC deficiency (76.9%), and six variants were newly detected—SERPINC1 c.398A > T (p.Gln133Leu), PROC c.450C > A (p.Tyr150Ter), c.715G > C (p.Gly239Arg) and c.866C > G (p.Pro289Arg), and PROS1 c.1468delA (p.Ile490fs) and c.1931T > A (p.Ile644Asn). Our data are consistent with those of previous studies, which mostly used time-consuming Sanger sequencing for genotyping, and the indication criteria for molecular genetic testing were adapted to this process in the past. Our promising results allow for a wider application of the described methodology in clinical practice, which will enable a suitable expansion of the group of indicated patients to include individuals with severe clinical findings of thrombosis at a young age. Moreover, this approach is flexible and applicable to other oligogenic panels.

Detection of new oral anticoagulant (NOAC) levels by screening, special and global tests, and liquid chromatography-coupled tandem mass spectrometry (LC-MS/MS) is important in clinical situations when the cause of bleeding needs to be determined. We compared a routine coagulation test, special function test for NOACs, global coagulation test, and an LC-MS/MS method that enables simultaneous determination of apixaban, dabigatran and rivaroxaban in human plasma within one analysis to determine the optimal indication of the comparison methods, including their limitations and interferences. This study was conducted on a set of blood samples from 116 patients treated with NOACs. The results of both specific dilute thrombin time (dTT) tests for dabigatran provided the same results as the activated partial thromboplastin time (aPTT) screening test in comparison with LC-MS/MS as a reference. The dTT assay HemosIL® showed better results for low concentrations when compared to LC-MS/MS than dTT HYPHEN® as HemosIL® uses a non-linear calibration curve. Results of the specific anti-Xa assay yielded better results than the prothrombin time test in comparison with LC-MS/MS as a reference, especially for apixaban, but also for rivaroxaban. Our LC MS/MS method is simply feasible, but only in a specialized laboratory. The method is easy-to-use for the simultaneous determination of all dabigatran, apixaban and rivaroxaban by LC-MS/MS within three minutes with a concentration range of 1 to 500 µg/L without dilution. In the normal practice of the coagulation laboratory, it is advisable to use specific tests for NOAC determination as screening and global assays are not sufficiently specific. The dTT test is the optimal choice for dabigatran determination and for xabans to determine anti-Xa activity. The LC-MS/MS method is suitable as an arbitration method for serious conditions.