Warfarin Induced Skin Necrosis

Warfarin-induced skin necrosis (WSN) is a rare thrombotic complication that occurs during initiation of oral anticoagulation therapy in patients with acute thromboembolic events. The presentation begins with intense skin pain quickly followed by erythema, hemorrhagic blisters, and, finally, full thickness skin necrosis, typically involving the breast, buttock, and thigh (64). The incidence of WSN was probably higher when it was customary to use warfarin loading doses of 15 -30 mg, to rapidly obtain a therapeutic prothrombin time, compared with the current standard practice of starting with 5-10 mg and adjusting subsequent doses based on daily INR results. A plausible mechanism for this rare adverse drug reaction is a rapid fall in protein C activity paralleling the decline in factor VII activity during the first 24 to 48 hours of warfarin therapy because both proteins have half-lives of approximately 6 hours and their synthesis is vitamin K-dependent (65). Although the prothrombin time is prolonged due to the decrease in factor VII activity, an anticoagulated state is not obtained until both factor X and prothrombin activities decline, which occurs more slowly. The result is a temporary hypercoaguable state and the potential to form subdermal venous thrombi and skin necrosis. Support for a pharmacogenetic mechanism is found in sporadic case reports of WSN occurring in patients with hereditary deficiencies of the natural anticoagulants [protein C (66), protein S (67), and antithrombin (68)], and FVL (69)]. This model is supported by the spontaneous occurrence of skin necrosis in neonates born with a homozygous deficiency of protein C (70). Due to the rarity of WSN, it is not possible to accurately calculate the risk of this adverse drug reaction in patients with or without inherited hypercoaguable risk factors. Rather than screening patients with acute VTE for these risk factors before starting warfarin, following standard anticoagulation practice guidelines for parenteral anticoagulation with heparin and warfarin is recommended (71).

How To Deal With Rosacea and Eczema

How To Deal With Rosacea and Eczema

Rosacea and Eczema are two skin conditions that are fairly commonly found throughout the world. Each of them is characterized by different features, and can be both discomfiting as well as result in undesirable appearance features. In a nutshell, theyre problems that many would want to deal with.

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