Pituitary apoplexy induced by a combined anterior pituitary test: case report and literature review.

We report the case of a 31-year-old woman with a pituitary adenoma who suffered symptomatic pituitary apoplexy. The patient developed a severe headache 2 min after undergoing a combined anterior pituitary function (CAP) test. Emergent computed tomography revealed a hemorrhagic pituitary tumor with evidence of a small subarachnoid hemorrhage. The headache improved spontaneously within half a day. Transsphenoidal surgery was performed 4 days later. Histologic examination demonstrated that the tumor was an eosinophilic adenoma with areas of diffuse hemorrhage. Although pituitary apoplexy caused by endocrinological testing has been reported in only 28 patients, apoplexy caused by a CAP test has been reported in only 1 patient. All of the previous cases had pituitary macroadenomas, 69% of which were involved in suprasellar extension. Non-functioning adenomas (24%) and prolactinomas (24%) were the most often affected by endocrine stimulation tests. With respect to the stimulants of pituitary adenomas, gonadotropin-releasing hormone (76%), TSH-releasing hormone (69%), and insulin (34%) were primarily responsible for the apoplexy. This case report with the literature review suggests that routine testing on pituitary function should be ordered cautiously given the risk of possible apoplexy.