Successful Heparin Desensitization: A Case Report and Review of the Literature

Heparin challenge test in patients undergoing cardiac surgery: dealing with heparin allergy

: A history of heparin hypersensitivity in patients undergoing cardiopulmonary bypass surgery poses the dilemma of which anticoagulant to use. Here, we report the successful use of a heparin challenge test in a 66-year-old female candidate for coronary artery bypass graft surgery with a past medical history of enoxaparin type I hypersensitivity after pulmonary embolism. Challenge and desensitization protocols are effectively used for essential antibiotics in patients with severe infections and/or allergies, or patients with aspirin intolerance requiring revascularization for coronary disease. A successful use of desensitization protocols to unfractionated heparin has been previously described in four patients undergoing cardiac surgery with various schemes. However, our case report indicates that a challenge test may also offer a quick, safe and effective approach in patients with a history of hypersensitivity reactions to heparin with inconclusive diagnostic tests and/or whenever the use of alternative heparins is tricky.

Recurrent intradialytic heparin induced anaphylaxis: workup and management

Heparin has been widely used for intradialytic anticoagulation since the 1940s. Heparin induced anaphylaxis can be life threatening, mandating early recognition and intervention. However, due to its relative rarity many physicians remain unaware. We report the case of a 70-year-old woman requiring dialysis, who developed recurrent anaphylaxis to intradialytic heparin. We describe a systematic approach to confirm the suspected heparin allergy, which must include an evaluation of predisposing factors, the dialysis equipment and concomitant medications. Further workup for safe alternatives employing skin prick and intradermal tests, as well as provocation tests are discussed.

Heparin-induced skin lesions

Heparins are widely used for prophylaxis and treatment of thromboembolic diseases. Besides bleeding complications, heparin-induced skin lesions are the most frequent unwanted adverse effects of subcutaneous heparin treatment. Evidence suggests that these lesions are more common than previously thought. Lesions are most frequently due to either allergic reactions or to possibly life-threatening heparin-induced thrombocytopenia. Early recognition and adequate treatment are highly important, because although both complications initially show a similar clinical picture, their treatment should be fundamentally different. Furthermore, risk factors associated with the patient, drug, and treatment regimen have been identified. We review the clinical range of heparin-induced skin lesions, emphasise evidence and controversies in epidemiology, diagnosis, and differential diagnosis, and discuss the management of patients with these skin lesions.