Anaphylactoid reaction to carboplatin: successful "desensitization"

Carboplatin (CP) hypersensitivity reactions have been reported in nearly 12 % of patients treated with this drug. The pathophysiologic mechanisms of these reactions have not been entirely elucidated. Various hypotheses are under discussion. CP hypersensitivity reactions could be IgE-mediated, caused by low-molecular platinum compounds acting as haptens. Platinum salts are also able to release histamine from basophils and mast cells, and some events seem to be non-immune-mediated direct histamine release. We report a case of CP tolerance induction in a 65-year-old man. During the third course of CP he experienced an anaphylactic reaction. Skin testing was negative. Suspecting the possibility of an anaphylactoid reaction due to histamine release, we developed a protocol to induce tolerance. Pre-medication with corticosteroid and antihistaminic was performed before intravenous CP infusion. The bag with CP was first infused 60 ml/h for 30 minutes; the infusion was well tolerated and infusion was continued at 100 ml/h for the next 60 minutes and thereafter at 120 ml/h until the bag was finished. Following this "desensitization", monthly courses of CP using the same protocol have been well tolerated.