[Activated C protein resistance manifested by cutaneous necrosis after interferon alpha injection: case report].

Introduction: Cutaneous necrosis occurring in the course of treatment by alpha interferon is an uncommon side-effect. Its physiopathologic mechanism remains obscure. A local thrombotic action of interferon has been suggested to explain its occurrence.

Exegesis: A 64-year-old male patient with human immunodeficiency virus-related cutaneous Kaposi's sarcoma presented cutaneous necrosis after a 9-month treatment by interferon alpha, while his resistance to activated protein C had already been demonstrated. To our knowledge, this is the first case ever described regarding the association of interferon-induced cutaneous necrosis with activated protein C resistance.

Conclusion: This suggests that in case of interferon treatment-induced cutaneous necrosis coagulation disorders should be investigated and questions the existence of a particular "pro-coagulant profile" facilitating this side effect.