Anaphylaxis and desensitization to the murine monoclonal antibody used for renal graft rejection.

The murine monoclonal antibody muromonab CD3 is currently used to reverse acute renal graft rejection. We report a case of systemic anaphylaxis during a muromonab CD3 infusion despite pretreatment with systemic antihistamines and corticosteroids. Rapid intravenous desensitization was performed the following day without untoward reactions and daily muromonab CD3 infusions were successful in reversing renal graft rejection. A second rapid desensitization to CD3 was performed 1 month later without any complications. Serum muromonab CD3-specific IgG and IgE antibodies were detected in serum samples obtained after the anaphylactic reaction. The anaphylactic reaction to muromonoab CD3 monoclonal antibody could have been due to allergen-specific antibodies noted in postreaction serum or a cross-reactive antibody to mouse antigens or both. More importantly, this case illustrates that rapid desensitization can be performed successfully without serious complications; therefore, systemic anaphylaxis can develop in susceptible atopic individuals receiving muromonab CD3 monoclonal antibody for renal graft rejection.