Acute adrenal failure associated with fluconazole after administration of high-dose cyclophosphamide

A 63-year-old man received high-dose cyclophosphamide for peripheral blood stem-cell (PBSC) harvest. He received 200 mg fluconazole. On day 3, atrial fibrillation developed with blood pressure declining to 78 mmHg. The rapid adrenocorticotropin (ACTH) test showed blunted adrenal responses. He was suspected as having adrenal failure, and fluconazole was discontinued. The rapid ACTH test became normal on Day 14, and PBSCs were successfully harvested. To clarify the association between adrenal failure and fluconazole, we resumed 400 mg fluconazole on Day 16 and repeated the test on Day 21, which showed blunted adrenal responses. This case demonstrates that prophylactic use of fluconazole can cause adrenal insufficiency.