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CYP2C9*3 polymorphism presenting as lethal subdural hematoma with low-dose warfarin.
Niteen D Karnik1, Kannan Sridharan2, D Tiwari1
1Department of Medicine, Seth Gordhandas Sunderdas Medical College and King Edward Memorial Hospital, Parel, Mumbai, Maharashtra, India.
Indian Journal of Pharmacology
|October 10, 2014
Summary
Warfarin dosing requires careful management due to high inter-individual response variability. Genetic analysis, specifically CYP2C9 polymorphism, is crucial for safe warfarin prescription and preventing adverse events like bleeding.
Area of Science:
- Pharmacogenetics
- Clinical Pharmacology
- Internal Medicine
Background:
- Warfarin is a widely used, cost-effective oral anticoagulant.
- Significant inter-individual variability exists in patient response to warfarin therapy.
- Pharmacogenetics offers insights into predicting warfarin dosage and mitigating bleeding risks.
Observation:
- A case report details a 49-year-old patient experiencing a fatal subdural hematoma while on low-dose warfarin.
- The patient was identified to have CYP2C9 gene polymorphism (*1/*3).
Findings:
- CYP2C9 gene polymorphism significantly impacts warfarin metabolism and efficacy.
- This genetic variation can lead to unexpected and severe adverse drug reactions, even at low doses.
Implications:
- Pre-prescription genetic testing for CYP2C9 variants is essential for personalized warfarin therapy.
- Integrating pharmacogenetics into clinical practice can improve patient safety and treatment outcomes.
- This case highlights the critical need for genetic assessment in warfarin management to prevent potentially lethal complications.
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