Fatal anaphylactoid reaction after primary exposure to aprotinin.

Aprotinin is widely used to prevent bleeding, inhibit systemic inflammatory response and reduce blood transfusions after cardiac surgery. Because it is a bovine protein, aprotinin can induce hypersensitivity reactions. We report a case of fatal anaphylactoid reaction to primary aprotinin exposure in a woman who was admitted for mitral valve replacement. The possibility of anaphylactic reaction should be considered whenever aprotinin is used.