A Case of Severe Anaphylactic Reaction Secondary to Isosulfan Blue Dye Injection

Allergic reactions including anaphylaxis resulting from isosulfan blue dye are rare but warrant a thorough review given that lymph node mapping has become an increasingly common procedure, putting more patients at risk.

Our patient was an 82-year-old female who underwent elective excision of a right forearm melanoma and right axillary sentinel lymph node mapping and suffered an anaphylactic reaction approximately 15 minutes after injection of isosulfan blue dye. The procedure was aborted. She was intubated; diphenhydramine and dexamethasone were administered; her blood pressure was stabilized with phenylephrine, epinephrine, and intravenous fluids; and she was transferred to the intensive care unit. She was extubated on postoperative day 1 and discharged home on postoperative day 2.

Sentinel lymph node biopsy is the standard of care for staging several cancers, and isosulfan blue is the dye most commonly used for this procedure. Reactions to the dye occur in some patients; however, we recommend the continued use of isosulfan blue dye for lymph node mapping given the low incidence of adverse effects, with no reported mortalities. Physicians should be prepared for the potential risk of anaphylactic shock.