Background: Cyclosporine injection is usually applied in allogeneic hematopoietic stem cell transplantation (Allo-HSCT) during induction phase. Anaphylaxis to cyclosporine injection is rare and how to deal with this issue in clinical practice is intractable.
Methods: We report a Chinese male patient with aplastic anemia who underwent allogeneic bone marrow transplantation (BMT) from his brother where HLA totally matched (10/10). Cyclosporine at a dose of 3 mg/kg was started by continuous infusion over 24 hours on day -1 of BMT and the patient showed sever anaphylaxis symptoms. He was then given oral capsules of cyclosporine (Sandimmun) at a conversion ratio 2:1. No further anaphylactic reaction was observed. The BM cells were successfully engrafted without causing severe GVHD. Moreover, frequent TDM monitoring as well as CYP3A4/CYP3A5/MDR1 genotyping were given so as to tailor the oral dosage of cyclosporine individually and prevent the adverse reaction between cyclosporine and posaconazole.
Results: The patient carried CYP3A5*3 GG genotype and the concentration of cyclosporine remained steady in the period of conversion and combination of cyclosporine and posaconazole. Consequently, the patient reported no allergy after conversion to oral cyclosporine.
Conclusions: Polyoxyethylated castor oil that is contained in cyclosporine may be the main allergen. Changing to oral capsules that do not contain this medicinal excipient instead of cyclosporine injection would no longer cause an allergic reaction. Rational use of immunosuppressants and prophylaxis antibiotics may need close cooperation between physicians and pharmacists to avoid side effects and harmful interactions.