Blue Hives

A 77-year-old woman underwent surgical resection of a 1.5-cm papillary carcinoma of the right breast. Isosulfan blue dye (8 ml) was used intraoperatively to define the associated lymphatic drainage.
Three sentinel nodes were excised from her axilla 5 minutes later, followed by the lumpectomy. By the time of wound closure, blue hives had developed on both upper arms and the chest as a result of an allergic reaction to the dye. Her cardiorespiratory system remained stable.

She was treated with intravenous phenylephrine (50 mg), had an uneventful recovery, and was discharged home 4 hours later. Blue hives occur in up to 1.5% of patients injected with this dye; the cause is probably a type I, IgE-mediated hypersensitivity to the dye.