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Updated: Aug 2, 2026
19:16
The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
Published on: March 18, 2010
[Priapism and activated protein C resistance]
Guillaume Guichard1, Pierre Charles Henry, Hugues Bittard
1Service d'Urologie, Hôpital Saint-Jacques, Besançon.
Summary
Priapism, a rare condition, can stem from clotting disorders. This case highlights heterozygous factor V Leiden mutation as a cause, emphasizing the need to investigate clotting issues in unexplained priapism.
Area of Science:
- Hematology
- Thrombosis
- Genetics
Background:
- Priapism is a rare condition that can be a symptom of underlying clotting disorders.
- Factor V Leiden mutation is a known genetic risk factor for thrombosis.
- Activated protein C resistance is a hypercoagulable state associated with Factor V Leiden.
Observation:
- The authors report a novel case of priapism in a patient with a heterozygous Factor V Leiden mutation.
- The patient was undergoing treatment with low molecular weight heparin.
- This is the first reported instance of priapism linked to a heterozygous mutation causing activated protein C resistance.
Findings:
- Heterozygous Factor V Leiden mutation can precipitate priapism, particularly when associated with activated protein C resistance.
- Low molecular weight heparin may not fully mitigate the thrombotic risk in susceptible individuals.
- Priapism should be recognized as a potential thromboembolic event.
Implications:
- Systematic screening for clotting disorders is crucial in patients presenting with priapism of unknown etiology.
- Understanding genetic predispositions like Factor V Leiden is vital for managing thrombotic risks.
- This case expands the spectrum of clinical presentations associated with Factor V Leiden mutation.
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