refludan and Thrombophilia

Heparin-induced thrombocytopenia (HIT) is an immune-mediated disorder caused by the development of antibodies to platelet factor 4 (PF4) and heparin. The thrombocytopenia is typically moderate, with a median platelet count nadir of approximately 50 to 60 x 10(9) platelets/L. Severe thrombocytopenia has been described in patients with HIT, and in these patients antibody levels are high and severe clinical outcomes have been reported (eg, disseminated intravascular coagulation with microvascular thrombosis). The timing of the thrombocytopenia in relation to the initiation of heparin therapy is critically important, with the platelet count beginning to drop within 5 to 10 days of starting heparin. A more rapid drop in the platelet count can occur in patients who have been recently exposed to heparin (within the preceding 3 months), due to preformed anti-heparin/PF4 antibodies. A delayed form of HIT has also been described that develops within days or weeks after the heparin has been discontinued. In contrast to other drug-induced thrombocytopenias, HIT is characterized by an increased risk for thromboembolic complications, primarily venous thromboembolism. Heparin and all heparin-containing products should be discontinued and an alternative, non-heparin anticoagulant initiated. Alternative agents that have been used effectively in patients with HIT include lepirudin, argatroban, bivalirudin, and danaparoid, although the last agent is not available in North America. Fondaparinux has been used in a small number of patients with HIT and generally appears to be safe. Warfarin therapy should not be initiated until the platelet count has recovered and the patient is systemically anticoagulated, and vitamin K should be administered to patients receiving warfarin at the time of diagnosis of HIT.

Topics: Anticoagulants; Arginine; Autoantibodies; Contraindications; Disseminated Intravascular Coagulation; Fondaparinux; Heparin; Hirudins; Humans; Pipecolic Acids; Platelet Count; Platelet Factor 4; Polysaccharides; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombophilia; Time Factors; Venous Thromboembolism; Vitamin K; Warfarin

Heparin-induced thrombocytopenia (HIT) is a serious and common complication of heparin therapy that can lead to significant losses of life and limb. It is often under-recognized and, therefore, goes untreated until thrombosis develops. This article is meant to provide specific recommendations for treating patients with immune-mediated HIT, whether or not it is associated with thrombosis. These recommendations are based on our clinical experience treating patients with HIT and our evaluation of the published data on the efficacy and safety of lepirudin and argatroban, the 2 drugs approved by the Food and Drug Administration for treating HIT. Based on these criteria, we consider lepirudin the treatment of choice in all patients with HIT except those with severe or deteriorating renal function.

Topics: Algorithms; Anticoagulants; Antigen-Antibody Complex; Arginine; Clinical Trials as Topic; Diagnosis, Differential; Disease Management; Follow-Up Studies; Hemorrhage; Heparin; Heparin, Low-Molecular-Weight; Hirudins; Humans; Immunoglobulin G; Pipecolic Acids; Platelet Activation; Platelet Count; Platelet Factor 4; Prognosis; Purpura, Thrombocytopenic, Idiopathic; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombophilia; Time Factors

Topics: Adult; Amputation, Surgical; Anticoagulants; Extremities; Female; Hirudins; Humans; Ischemia; Male; Middle Aged; Peripheral Vascular Diseases; Recombinant Proteins; Thrombin; Thrombophilia

Topics: Adult; Anticoagulants; Antithrombins; Budd-Chiari Syndrome; Cholecystitis; Disease Progression; Drug Resistance; Drug-Related Side Effects and Adverse Reactions; Factor V; Female; Follow-Up Studies; Hirudins; Humans; Infusions, Intravenous; Injections, Subcutaneous; Mutation; Odds Ratio; Recombinant Proteins; Thrombophilia; Treatment Outcome

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