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. 1986 Mar;21(3):289–293. doi: 10.1111/j.1365-2125.1986.tb05192.x

Abnormal vitamin K metabolism in the presence of normal clotting factor activity in factory workers exposed to 4-hydroxycoumarins.

B K Park, I A Choonara, B P Haynes, A M Breckenridge, R G Malia, F E Preston
PMCID: PMC1400858  PMID: 3964529

Abstract

The case histories of two patients exposed to the novel anticoagulants brodifacoum and difenacoum are reported. Abnormal vitamin K1 metabolism, as indicated by elevated vitamin K1 2,3-epoxide plasma concentrations after i.v. administration of vitamin K1, could be detected for more than 18 months after exposure to the anticoagulants. There was a marked prolongation of prothrombin time (greater than 50 s) in both cases, at the time of exposure. However, subsequent haematological investigations (prothrombin time and vitamin K-dependent clotting factor activity) have been shown to be normal in both cases for at least 18 months. These cases confirm the long-acting nature of brodifacoum and difenacoum and present an apparent dissociation between the effect of coumarin anticoagulants on vitamin K1 metabolism and clotting factor activity.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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