Abstract
Floseal Hemostatic Matrix is a topical hemostatic agent used across specialties and commonly applied to the renal bed during partial nephrectomy. Here we present the first adult case of Floseal allergy in the literature. A 62-year-old man underwent partial nephrectomy for a Bosniak type IV cyst. After unclamping the kidney, the patient declined precipitously, later determined due to an anaphylactic reaction to the Floseal placed on the renal bed. The patient had a prolonged anaphylactic reaction that required ionotropic support for over 24 h, possibly due to continued exposure. His tryptase level was elevated, and allergy testing revealed an allergy to the gelatin matrix component of the Floseal. Floseal anaphylaxis should be considered during episodes of cardiovascular collapse after drug administration. However, consideration should be given to removing it to prevent continued exposure and weighed against the risk of prolonged surgery in an anaphylactic patient.