Laboratory hemostasis: milestones in Clinical Chemistry and Laboratory Medicine

Abstract

Hemostasis is a delicate, dynamic and intricate system, in which pro-and anti-coagulant forces cooperate for either maintaining blood fluidity under normal conditions, or else will prompt blood clot generation to limit the bleeding when the integrity of blood vessels is jeopardized. Excessive prevalence of anticoagulant forces leads to hemorrhage, whereas excessive activation of procoagulant forces triggers excessive coagulation and thrombosis. The hemostasis laboratory performs a variety of first, second and third line tests, and plays a pivotal role in diagnostic and monitoring of most hemostasis disturbances. Since the leading targets of Clinical Chemistry and Laboratory Medicine include promotion of progress in fundamental and applied research, along with publication of guidelines and recommendations in laboratory diagnostics, this journal is an ideal source of information on current developments in the laboratory technology of hemostasis, and this article is aimed to celebrate some of the most important and popular articles ever published by the journal in the filed of laboratory hemostasis.

Detection of mild inherited disorders of blood coagulation: current options and personal recommendations

“…This is confirmed by the fact that blood coagulation is prevalently activated by the TF-FVIIa pathway and that patients with even severe FXII deficiencies do not exhibit a clinically relevant bleeding phenotype [17]. The entire blood coagulation pathway is modulated at various stages by the activity of a number of physiological inhibitors, which mainly include tissue factor pathway inhibitor, the protein C and S system and antithrombin [16]. After conversion of fibrinogen to fibrin by thrombinmediated cleavage of fibrinopeptides A and B, the soluble fibrin monomers are then converted into an insoluble fibrin gel by covalent cross-linking catalyzed by FXIIIa, and this fibrin gel ultimately stabilizes the original platelet plug.…”

“…The complex between activated factor IX and its co-factor FVIII converges into the common pathway, and is hence effective to activate FX to FXa. Interestingly, the amount of thrombin generated by these pathways is relatively modest, lower than 5% of the total amount required for the effective fibrin generation that would be sufficient for successful stabilization of the platelet plug [16]. It is exactly at this point that the factors of the intrinsic (contact) pathway come into play, according to a model conventionally known as the 'thrombin burst'.…”

“…Classification & prevalence of mild inherited bleeding disorders 'Process disturbances' to the initiation and further development of blood coagulation may result in an imbalance between prothrombotic and antithrombotic forces, which may then alternatively predispose individuals to excessive bleeding (i.e., ineffective hemostasis activation or development) or thrombosis (excessive hemostasis activation or development) [2,16,18].…”

False myths and legends in laboratory diagnostics

“…Pathological derangements of the delicate hemostatic balance may alternatively expose the patient to ineffective coagulation and bleeding (i.e., hypofunction), or excess clotting and thrombosis (i.e., hyperfunction) [3]. Along with mounting evidences that shortened values of APTT may reflect a prothrombotic state [4], prolonged values have been historically associated with a potential hemorrhagic risk.…”

Thrombophilia testing. Useful or hype?

“…Indeed, the coagulation laboratory has an enormous potential for investigation of patients with VTE [7], but all these weapons must be used with moderation and intelligence. In the general perspective of values-based reimbursement and accountability of laboratory performance, there is general consensus that a diagnostic test is only useful when it has an influence on clinical management, when it improves the outcome or, preferably, reverses an adverse outcome.…”