chondroitin-sulfates and Purpura--Thrombocytopenic--Idiopathic

Platelets participate in a variety of responses of the blood to injury. An emerging body of evidence suggests that these cells express an intrinsic capacity to interact with and trigger both classical and alternative pathways of complement. This activity requires cell activation with biochemical agonists and/or shear stress, and is associated with the expression of P-selectin, gC1qR, and chondroitin sulfate. Platelet mediated complement activation measurably increases soluble inflammatory mediators (C3a and C5a). Platelets may also serve as targets of classical complement activation in autoimmune conditions such as antiphospholipid syndromes (APS) and immune thrombocytopenia purpura (ITP). Retrospective correlation with clinical data suggests that enhanced platelet associated complement activation correlates with increased arterial thrombotic events in patients with lupus erythematosus and APS, and evidence of enhanced platelet clearance from the circulation in patients with ITP. Taken together, these data support a role for platelet mediated complement activation in vascular inflammation and thrombosis.

Topics: Animals; Antiphospholipid Syndrome; Blood Platelets; Carrier Proteins; Chondroitin Sulfates; Complement Activation; Complement C3a; Complement C5a; Humans; Inflammation Mediators; Lupus Erythematosus, Systemic; Mitochondrial Proteins; P-Selectin; Purpura, Thrombocytopenic, Idiopathic; Thrombosis; Vasculitis

Heparin-induced thrombocytopenia/thrombosis is an immunologic reaction to unfractionated heparin characterized by thrombocytopenia, platelet activation and thrombosis. A high index of suspicion is required for timely diagnosis and treatment. Treatment is complex and outcome maybe less then satisfactory.

Topics: Ancrod; Antibodies; Anticoagulants; Arginine; Cardiovascular Diseases; Chondroitin Sulfates; Dermatan Sulfate; Fibrinolytic Agents; Heparin; Heparin, Low-Molecular-Weight; Heparitin Sulfate; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Practice Guidelines as Topic; Purpura, Thrombocytopenic, Idiopathic; Recombinant Proteins; Sulfonamides; Thrombin

Danaparoid is a safe and effective drug for the treatment of heparin-induced thrombocytopenia (HIT). We describe an uncommon complication: danaparoid cross-reactivity with HIT antibodies.. A retrospective observational multicenter study on HIT was conducted in France. In this study concerning HIT patients treated with lepirudin, 12 patients were treated with lepirudin because danaparoid cross-reacted with the heparin-dependent antibodies.. Three groups of situations can be separated. In a first group, four patients received a short course of danaparoid until their initial functional HIT assay showed a cross-reactivity between danaparoid and HIT antibodies. One patient presented a fatal thrombotic complication but the relationship between this thrombotic complication and danaparoid cross-reactivity cannot be certain. In a second group, four patients received for 4 days at least a danaparoid treatment while the initial functional test did not show any danaparoid cross-reactivity. During danaparoid treatment, no significant increase of platelet count was observed and two patients presented a fatal thrombotic complication. In a third group, cross-reactivity between danaparoid and HIT antibodies was not checked before danaparoid therapy. During danaparoid treatment, no significant increase of platelet count was observed and the four patients developed a venous thromboembolic complication.. Absence of any increase in platelet count after 3 to 5 days of danaparoid therapy and/or the occurrence of a new thrombotic event should lead to danaparoid cross-reactivity suspicion. However, before attributing thrombotic complications to danaparoid cross-reactivity, it is crucial to verify that the patients received the recommended danaparoid dosage regimen.

Topics: Aged; Anticoagulants; Chondroitin Sulfates; Cross Reactions; Dermatan Sulfate; Female; Hemostasis; Heparin; Heparitin Sulfate; Hirudins; Humans; Intensive Care Units; Male; Middle Aged; Purpura, Thrombocytopenic, Idiopathic; Recombinant Proteins; Retrospective Studies

Immune-mediated heparin-induced thrombocytopenia (HIT) is an uncommon but serious complication of therapy with heparins. It affects all ages and requires replacement of the causative anticoagulant. However, information on alternative antithrombotic use in children with HIT is limited. This paper reviews 27 published and 7 unpublished case reports of children aged 2 weeks to 17 years treated with danaparoid. Thirty-three suffered from HIT or suspected HIT, and 1 child without HIT had a high bleeding risk. All children had severe underlying problems increasing their thrombotic and/or bleeding risk. HIT diagnosis was confirmed serologically or clinically in 26 cases (78.8%). Danaparoid regimens were similar to those used in adults, but in general, younger children needed higher daily doses of danaparoid to achieve the same target plasma anti-Xa levels than teenagers or adults. Of those with a known outcome 28/33 children (84.8%) survived, 7 having suffered from a serious adverse event. Five deaths occurred including 1 thrombotic and 2 major bleeds. Three of the in total 4 major bleeding events occurred in children undergoing surgery with cardiopulmonary bypass. We conclude that despite the reported adverse events danaparoid can be used as an alternative antithrombotic for children who are intolerant of the heparins, except in cases requiring cardiopulmonary bypass surgery.

Topics: Adolescent; Adult; Child; Child, Preschool; Chondroitin Sulfates; Dermatan Sulfate; Drug Evaluation; Fibrinolytic Agents; Hemorrhage; Heparin; Heparitin Sulfate; Humans; Infant; Infant, Newborn; Male; Purpura, Thrombocytopenic, Idiopathic; Risk Factors; Thrombosis

We report the case of 64-year-old female patient with pulmonary embolism and bilateral femoropopliteal deep vein thrombosis caused by heparin-induced thrombocytopenia type II (HIT II) resistant to danaparoid sodium and subsequently administered lepirudin in whom a single late plasmapheresis performed on day 6 of the initiation of treatment of HIT reversed the course of the disease, preventing its highly potential fatal outcome. Primarily administered lepirudin was not only ineffective but even led to further aggravation of the patient's clinical state and platelet count drop in the first stage of the HIT treatment. The improvement of the patient's clinical state was not achieved before therapeutic plasma exchange (TPE) had removed the greatest part of pathogenetic circulating substrate. Only after TPE, lepirudin, introduced again, led to the platelet count recovery. In the subsequent course of the treatment, lepirudin was combined with an overlapping oral anticoagulant. Previously positive heparin aggregation test and fast particle gel heparin-platelet factor 4 immunoassay were normalized as well as the patient's clinical status. Early plasmapheresis, administered within 4 days of the onset of thrombocytopenia in HIT, as a beneficial therapeutic measure in certain individual cases, is indisputable. However, our results do not concur with previously reported findings of the so far most comprehensive study on plasmapheresis performed in the management of HIT with thrombosis, discrediting late plasmapheresis administered 4 days after the onset of the disease not only as ineffective, but even as an aggravating factor. Our results suggest the possible beneficial impact of late plasmapheresis as a method that may reverse a prothrombotic process and lead to a fast improvement in the patient's platelet count, especially in cases initially resistant to thrombin inhibitors.

Topics: Arthroplasty, Replacement, Hip; Autoantibodies; Chondroitin Sulfates; Dermatan Sulfate; Drug Resistance; Female; Fibrinolytic Agents; Heparin; Heparitin Sulfate; Hip Fractures; Hirudins; Humans; Middle Aged; Partial Thromboplastin Time; Plasma; Plasmapheresis; Postoperative Complications; Pulmonary Embolism; Purpura, Thrombocytopenic, Idiopathic; Recombinant Proteins; Salvage Therapy; Thrombophilia; Time Factors

Patients with heparin-induced thrombocytopenia urgently requiring surgery with cardiopulmonary bypass (CPB) present a unique management challenge that must be addressed by the use of alternative anticoagulants. Although clinical success with the direct thrombin inhibitor hirudin has been reported, there is sparse information in the literature supporting the efficacy of this drug as an anti-thrombotic to prevent fibrin formation during CPB. In this report, we describe the efficacy of this drug to prevent thrombin-mediated fibrin formation during CPB.

Topics: Adult; Anticoagulants; Cardiopulmonary Bypass; Chondroitin Sulfates; Contraindications; Dermatan Sulfate; Endarterectomy; Fibrinolytic Agents; Fibrinopeptide A; Heparin; Heparitin Sulfate; Hirudins; Humans; Hypertension, Pulmonary; Hypothermia, Induced; Male; Peptide Fragments; Postoperative Complications; Prothrombin; Pulmonary Embolism; Purpura, Thrombocytopenic, Idiopathic; Recombinant Proteins; Thrombectomy; Thrombin; Thrombosis