Anaphylaxis to gadobenate dimeglumine (Multihance): a case report.

Background: Gadolinium chelates are relatively safe contrast media used in MRI. Immediate severe adverse effects are exceptionally rare and mostly concern mild anaphylactoid reactions. We report a case of anaphylaxis to gadobenate dimeglumine (Gd-BOPTA, Multihance), a gadolinium-based contrast agent.

Methods: A 32-year-old female patient with a personal history of multiple sclerosis, while undergoing an MRI scan, developed bronchospasm and acute urticaria with diffuse giant pruritic plaques in the first minute of Gd-BOPTA infusion. The procedure was cancelled and acute treatment of the reaction took place. The patient reported 2 additional MRI scans with definite use of unknown contrast media in the past 2 years without any adverse effect. Blood samples were obtained 2 and 48 h after the reaction for measurement of serum tryptase concentration (Pharmacia Diagnostics, Uppsala, Sweden). Skin prick tests and intradermal tests were performed using 1:1,000, 1:100 and 1:10 dilution of the offending agent and alternative gadolinium-based agents [gadodiamide (Omniscan) and gadoteric acid (Dotarem)]. A group of 10 nonatopic individuals who underwent the same skin testing comprised the control group.

Results: Tryptase concentration was highly elevated 2 h after the reaction (21 microg/l) compared with that at 48 h (3 microg/l). Skin prick tests in our patient were all negative, while intradermal testing with 0.03 ml of 1:100 and 1:10 preparations of Multihance showed a definite positive wheal-and-flare reaction. Skin tests to the alternative agents showed no response. In the control group, all performed tests were negative.

Conclusion: We report the first case of an allergic reaction to gadobenate dimeglumine. Besides, skin testing seems to be a precious diagnostic tool which, if positive, strongly suggests a mast cell-mediated underlying mechanism.