Abstract | PURPOSE OF REVIEW: RECENT FINDINGS: The pathophysiology of unfractionated heparin-induced thrombocytopenia, caused by the development of antibodies to heparin/ platelet factor 4 complexes, holds true for low-molecular-weight heparin because the molecules of the latter are of the same saccharidic structure as those of unfractionated heparin. Owing to their smaller size, however, low-molecular-weight heparin does not interact with platelet factor 4 and platelets as efficiently as does unfractionated heparin. This translates to a two- to threefold lower risk of immune sensitization (antibody generation and occurrence of clinical heparin-induced thrombocytopenia). Low-molecular-weight heparin-induced thrombocytopenia antibodies are more often immunoglobulin A and immunoglobulin M, in contrast to the immunoglobulin G antibodies generated with unfractionated heparin-induced thrombocytopenia, which tend to be more often associated with clinical heparin-induced thrombocytopenia. The clinical expression of low-molecular-weight heparin-induced thrombocytopenia is generally similar to that of unfractionated heparin-induced thrombocytopenia but can have a slower onset, more severe thrombocytopenia, and slower platelet count recovery. Given that low-molecular-weight heparin, of itself, is linked with heparin-induced thrombocytopenia pathophysiology and it can interact with most preexisting heparin-induced thrombocytopenia antibodies generated after exposure to unfractionated heparin, treatment of heparin-induced thrombocytopenia patients with low-molecular-weight heparin is contraindicated. SUMMARY:
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Authors | Jeanine M Walenga, Margaret Prechel, Walter P Jeske, Mamdouh Bakhos |
Journal | Current opinion in pulmonary medicine
(Curr Opin Pulm Med)
Vol. 11
Issue 5
Pg. 385-91
(Sep 2005)
ISSN: 1070-5287 [Print] United States |
PMID | 16093810
(Publication Type: Comparative Study, Journal Article, Review)
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Chemical References |
- Anticoagulants
- Heparin, Low-Molecular-Weight
- Heparin
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Topics |
- Anticoagulants
(adverse effects)
- Contraindications
- Heparin
(adverse effects)
- Heparin, Low-Molecular-Weight
(adverse effects)
- Humans
- Thrombocytopenia
(chemically induced, immunology, physiopathology)
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