title: The use of low dose Orgaran in heparin-induced thrombocytopenia associated with in vitro platelet aggregation at higher Orgaran concentrations.
abstract: We report a case of heparin-induced thrombocytopenia with in vitro antibody cross-reactivity by platelet aggregometry to both low molecular weight heparin and the heparinoid Org 10172 (Orgaran). The in vitro reactivity with Orgaran was only present at the upper limit of concentrations that would normally be used therapeutically. Low dose Orgaran therapy was initiated, allowing successful renal replacement therapy without invoking further thrombocytopenia or thrombosis. Interestingly, in vitro platelet aggregometry following treatment did not reveal increasing sensitivity to Orgaran. This case indicates that negative in vitro platelet aggregometry at defined lower concentrations of Orgaran may predict in vivo safety at the same levels despite positive platelet aggregometry reactions at higher concentrations of Orgaran.
authors.affiliation: Department of Haematology, Christchurch Hospital, New Zealand.
authors.forename: G R
authors.initials: GR
authors.lastname: Hill
authors.forename: C
authors.initials: C
authors.lastname: Hickton
authors.forename: S
authors.initials: S
authors.lastname: Henderson
authors.forename: W N
authors.initials: WN
authors.lastname: Patton
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage / Q000627:therapeutic use*; D002809:Chondroitin Sulfates / Q000008:administration & dosage / Q000627:therapeutic use*; D003871:Dermatan Sulfate / Q000008:administration & dosage / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D006493:Heparin / Q000009:adverse effects*; D006497:Heparan Sulfate / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects* / Q000276:immunology; D015203:Reproducibility of Results; D013921:Thrombocytopenia / Q000139:chemically induced / Q000188:drug therapy* / Q000276:immunology
chemical_list: D000925:Anticoagulants; D002809:Chondroitin Sulfates; D003871:Dermatan Sulfate; D006493:Heparin; D006497:Heparan Sulfate; C035838:danaparoid