[Vascular involvement in Cogan's syndrome.  A case report]. 
Vascular manifestations of Cogan's syndrome are rarely reported.  We report the case of a young woman followed for typical Cogan's disease.  Serious vascular involvement was found only during work-up for arterial hypertension.  This case highlights potentially asymptomatic nature of extensive vasculitis affecting large and medium-sized vessels in Cogan's disease.  Careful screening is required to prevent life-threatening complications.