Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis
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Blood Coagul. Fibrinolysis · Oct 2010
Case ReportsDysfibrinogenemia in childhood: two cases of congenital dysfibrinogens.
A 2-year-old asymptomatic boy and his relatives were investigated for a suspected fibrinogen mutation after coagulation tests revealed a decreased functional fibrinogen level (family A). Eight-year-old and 1-year-old asymptomatic brothers were investigated for a suspected fibrinogen mutation after coagulation tests revealed a decreased functional fibrinogen level and prolonged thrombin time (family B). To identify whether genetic mutations were responsible for these dysfibrinogens, DNA extracted from the blood was analyzed. ⋯ Mass spectroscopy showed the presence of mutant fibrinogen chains in circulation. Scanning electron microscopy revealed thicker fibrin fibers, differing significantly from the normal control in both cases. Two cases of asymptomatic dysfibrinogenemias, found by routine coagulation testing, were genetically identified as new cases of fibrinogen variants Aα Arg16His and Aα Arg16Cys.
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Changes in coagulation may have a profound impact on outcomes following severe burns and the coagulation abnormalities after thermal injury are incompletely described. We postulated that thermal injury induces a systemic hypercoagulable state. With Institutional Review Board approval, five patients were consented for enrollment in this case series. ⋯ Burns greater than 6% appear to induce a systemic hypercoagulable state with a phase and magnitude relationship proportional to total body surface area burned. Severe burns greater than 40% appear to induce a consumptive coagulopathy. Prothrombin fragment 1.2 may represent a useful screening test for a burn-induced hypercoagulable state.
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Blood Coagul. Fibrinolysis · Sep 2010
Thrombophilia and the risk of thromboembolic events in women on oral contraceptives and hormone replacement therapy.
Thrombophilia contributes to the risk of thrombosis in women using female hormones. The objective of the present study was to evaluate the prevalence of thrombophilia in women with thromboembolic events (TEEs) using oral contraceptives or hormone replacement therapy (HRT) and assess the contribution of a family history and the duration of hormone use in predicting thrombosis. A retrospective analysis was performed of the case records of women who developed a TEE while on oral contraceptives or HRT and were referred for thrombophilia evaluation over a 4-year period. ⋯ Approximately half of the women had been taking oral contraceptives or HRT for more than 1 year. There is a high prevalence of thrombophilia in women who developed a TEE while using oral contraceptives or HRT for more than 1 year. Family and personal history of thrombosis should be carefully evaluated in all women before initiating or continuing oral contraceptives or HRT, and a positive history may warrant a thrombophilia screening.
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Blood Coagul. Fibrinolysis · Sep 2010
Factor VIIa analog has marked effects on platelet function and clot kinetics in blood from patients with hemophilia A.
To evaluate the hemostatic effects of NN1731 and rFVIIa, an ex-vivo study in hemophilia patients used the Hemodyne Hemostasis Analysis System (HAS) to measure platelet contractile force (PCF), clot elastic modulus (CEM), and force onset time (FOT), and the Haemoscope Thrombelastograph (TEG) to measure reaction time (R), kinetics time (K), and maximum amplitude (MA). Blood samples from 10 healthy volunteers and 10 Factor VIII-deficient patients of varying severity (mild, moderate, severe), were spiked with rFVIIa and NN1731 (both 0.64 and 1.28 microg/ml, respectively) and analyzed to characterize platelet function and clot kinetics. There was wide variability in the rFVIIa response. ⋯ No correlation was observed between CEM and MA. NN1731 produced less variable, more pronounced and predictable ex-vivo hemostatic effects on PCF, CEM, FOT, R and K than rFVIIa in all hemophilia groups. HAS and TEG assays provided similar estimates of FOT and R, however CEM appeared to be more sensitive than MA to changes in clot firmness.