'Empty sella syndrome': a case of a patient with sodium succinate hydrocortisone allergy.

We present the case of a woman with 'empty sella syndrome' who experienced generalized urticaria after the administration of sodium succinate hydrocortisone in two episodes. The patient underwent an allergological evaluation (prick, intradermal, and patch tests) with hydrocortisone sodium succinate, hydrocortisone acetate, hydrocortisone, hydrocortisone sodium phosphate, methylprednisolone hemisuccinate, methylprednisolone, and preservatives held in the formulation of sodium succinate hydrocortisone (sodium phosphate and methyl-p-oxybenzoate). The basophil activation test (BAT) was also performed with hydrocortisone. The single-blind i.m. challenge test was performed with hydrocortisone sodium phosphate in 4 days. Skin test with hydrocortisone sodium succinate and methylprednisolone hemisuccinate was positive. On the contrary, allergological tests performed with other formulations of the same steroids and preservatives were negative. These results showed an immediate-type allergy to succinate ester. BAT was not helpful to improve our diagnostic work-up because our patient was a 'nonresponder.' Therefore, the patient underwent successfully to a challenge test with hydrocortisone sodium phosphate. Patients with succinate ester allergy can tolerate alternative corticosteroids without ester.