Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis
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Blood Coagul. Fibrinolysis · Oct 2011
Case ReportsPlatelet-mediated thrombolysis in patients with δ-storage pool deficiency: a thrombelastographic analysis.
We present the first thrombelastographic descriptions of three patients with δ-storage pool deficiency, a platelet disorder that involves a deficiency of dense granules and moderate bleeding. The patients demonstrated a 49-54% loss of platelet-mediated clot strength over a 1-2-h period after normal thrombus formation. This pattern persisted, with some attenuation of loss of strength following administration of epsilon aminocaproic acid, desmopressin and platelets for tonsillectomy. Assessment of platelet function in patients with platelet granule disorders can be accomplished with thrombelastographic methods in ambulatory and perioperative settings; however, the effects of therapy for this disorder cannot be monitored with thrombelastography without obtaining a blood sample prior to prophylactic hemostatic intervention.
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Blood Coagul. Fibrinolysis · Oct 2011
Protamine reversal of low molecular weight heparin: clinically effective?
Low molecular weight heparins (LMWHs) are frequently used in the prophylaxis or treatment of venous thrombosis, acute coronary syndromes and peri-operative bridging. Major bleeding occurs in 1-4% depending on dose and underlying condition. Protamine is recommended for reversal but only partially reverses the anti-Xa activity and there are very limited data on clinical effectiveness. ⋯ Protamine may be of use in reversing bleeding associated with LMWH but not in all patients. Anti-Xa levels were useful to assess the amount of anticoagulation before protamine administration but unhelpful in assessing its effect. Better reversal agents and methods to monitor LMWH therapy are required.
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Blood Coagul. Fibrinolysis · Oct 2011
Case ReportsDiagnosis of Heyde's syndrome by abnormal closure times despite normal von Willebrand's activity.
Heyde's syndrome is characterized by iron deficiency anemia due to gastrointestinal bleeding and calcific aortic stenosis. Patients with this syndrome have a bleeding diathesis due to a loss of the largest multimers of von Willebrand factor (vWF). Here we present a case of Heyde's syndrome diagnosed with abnormal closure times and normal vWF Ristocetin cofactor activity (vWF:Rco). ⋯ Postoperatively, these closure times normalized. What is unique about our current report is that we measured both vWF:Rco and closure times, the two readily available assays in most coagulation laboratories. vWF:Rco is a standard assay for measuring platelet activity but may miss defects in platelet aggregation that are only seen under high shear stress. As the closure times can detect such defects, it is perhaps more representative than traditional assays, and in situations such as our case, closure times may be the only method by which subtle abnormalities in vWF function could be detected.
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Blood Coagul. Fibrinolysis · Sep 2011
Plasminogen activator inhibitor type-1 deficiency exaggerates LPS-induced acute lung injury through enhancing Toll-like receptor 4 signaling pathway.
Mice lacking plasminogen activator inhibitor-1 (PAI-1) did not affect lung injury induced by gram-positive bacteria pneumococcal pneumonia but worsened lung injury induced by gram-negative bacteria Klebsiella. The exact mechanisms have not been completely elucidated. In this study, we examined the signaling pathway of Toll-like receptor 4 (TLR4) with/without PAI-1 in acute lung injury (ALI) induced by lipopolysaccharides (LPS) in mice. ⋯ In addition, expression of TLR4 was up-regulated and the phosphorylation activation of extracellular regulating kinase (ERK) and c-Jun N-terminal kinase (JNK) were also increased in PAI-1 knockout mice compared to wild-type mice. Inversely, interleukin (IL)-1 receptor-associated kinase-M (IRAK-M) and suppressor of cytokine signaling 1 (SOCS1) were both significantly reduced in PAI-1-/-mice after LPS challenge. PAI-1 deletion increased lung injury induced by LPS through up-regulation of TLR4, ERK and C-JNK and down-regulation of TLR4 negative regulators.
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Blood Coagul. Fibrinolysis · Jul 2011
Bleeding symptoms in heterozygous carriers of inherited coagulation disorders in southern Iran.
The objective of the present study was to investigate the prevalence of bleeding symptoms in individuals who are heterozygous for recessively inherited coagulation disorders (RICDs) and to determine the association of these bleeding symptoms with type of RICDs. This was a retrospective cross-sectional study being performed in Shiraz Hemophilia Society (Shiraz, Southern Iran). In this study, bleeding symptoms of the parents (heterozygous) of the patients (homozygous) who were registered and had definite diagnosis as autosomal recessive coagulation disorder were evaluated. ⋯ Heterozygosity for factor X and XIII deficiency was associated with prolonged or massive bleeding during operations (P=0.001) and after minor traumas (P=0.019), respectively. Heterozygosity for RICDs is associated with some bleeding symptoms. Thus bleeding tendency and homeostasis disturbance should be kept in mind in those who are heterozygous for RICDs and more preoperative care and correction of coagulation indices is highly recommended.