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Updated: May 15, 2026
07:49
Measuring Local Anaphylaxis in Mice
Published on: October 14, 2014
Allergic anaphylaxis due to subcutaneously injected heparin
1Department of Dermatology, Venereology, and Allergology, University Hospital of Würzburg, Josef-Schneider-Str, 2, Würzburg, 97080, Germany. Anders_D@klinik.uni-wuerzburg.de.
Summary
Severe anaphylaxis after enoxaparin injection suggests a rare IgE-mediated hypersensitivity to heparins. Alternative anticoagulants like hirudins offer safer options due to distinct molecular structures.
Area of Science:
- Immunology
- Pharmacology
Background:
- Heparins are widely used anticoagulants.
- Immune-mediated hypersensitivity reactions to heparins are rare but can occur.
- Delayed-type reactions are common, but immediate anaphylactic reactions are extremely rare.
Observation:
- A 43-year-old patient experienced severe anaphylaxis within minutes of subcutaneous enoxaparin injection.
- Skin prick testing indicated a probable allergic mechanism, showing cross-reactivity among different heparin preparations.
- In-vitro basophil activation tests were negative.
Findings:
- The patient's history, symptoms, and skin test results strongly suggested an IgE-mediated allergic hypersensitivity to heparins.
- The reaction was likely due to the heparin itself, not contaminants, given the positive skin tests.
Implications:
- This case highlights the possibility of true allergic reactions to heparins, distinct from non-allergic anaphylaxis.
- Patients with heparin allergy can be safely treated with anticoagulants having different molecular structures, such as coumarins, hirudins, or direct thrombin inhibitors.
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