Background: We report a documented grade III IgE-mediated hypersensitivity reaction associated with the use of 2.5% patent blue V dye for sentinel lymph node biopsy during breast cancer surgery.
Methods: Immediately after the reaction, when hemodynamic stability was obtained, plasma histamine was measured whereas serum tryptase was not. Six weeks later, with the patient's consent, cutaneous tests to patent blue V dye, methylene blue dye, latex and all drugs used during surgery were performed according to standardized procedures.
Results and conclusion: Clinical symptoms, biological assessment results and cutaneous tests positivity confirmed the onset of an anaphylactic reaction due to patent blue V. Of interest, the positivity of the cutaneous tests observed with patent blue V was not found with methylene blue which might be proposed for further investigations in our patient. This case report confirms the need for systematic allergological investigation of all drugs and substances administered during the peri-operative period in case of an immediate hypersensitivity reaction occurring during anesthesia.