title: Excessive anticoagulation and anaphylactic reaction after rechallenge with lepirudin in a patient with heparin-induced thrombocytopenia.
abstract: Approximately 40% of patients who receive lepirudin for 5-10 days develop antihirudin antibodies. These antibodies lead to decreased renal elimination of lepirudin, ultimately resulting in elevated activated partial thromboplastin times (aPTTs). A small percentage of patients with antihirudin antibodies develop hypersensitivity reactions to lepirudin with reexposure. Thus, patients who are reexposed to lepirudin must be monitored closely for hypersensitivity. A 45-year-old African-American woman received lepirudin for anticoagulation after being diagnosed with heparin-induced thrombocytopenia type II. She developed supratherapeutic aPTTs after 10 days of lepirudin therapy. Lepirudin was then withheld for 6 days, during which her aPTT remained supratherapeutic. After lepirudin infusion was restarted, the patient developed an anaphylactic reaction. She was treated appropriately with an antihistamine, a corticosteroid, and an anxiolytic agent. After the reaction resolved, the patient was rechallenged with lepirudin, and the anaphylactic reaction recurred.
authors.affiliation: Department of Pharmacy, Piedmont Hospital, Atlanta 30309, Georgia, USA. naadede.badger@piedmont.org
authors.forename: NaaDede O
authors.initials: NO
authors.lastname: Badger
authors.forename: Kim
authors.initials: K
authors.lastname: Butler
authors.forename: Laura C
authors.initials: LC
authors.lastname: Hallman
mesh_terms: D000707:Anaphylaxis / Q000209:etiology*; D000925:Anticoagulants / Q000009:adverse effects*; D005260:Female; D006493:Heparin / Q000009:adverse effects*; D006629:Hirudins / Q000009:adverse effects* / Q000031:analogs & derivatives* / Q000276:immunology; D006801:Humans; D008875:Middle Aged; D011994:Recombinant Proteins / Q000009:adverse effects*; D013921:Thrombocytopenia / Q000139:chemically induced*
chemical_list: D000925:Anticoagulants; D006629:Hirudins; D011994:Recombinant Proteins; D006493:Heparin; C083544:lepirudin