Pituitary apoplexy caused by endocrine stimulation tests: a case report.

The case of a 60-year-old woman with a giant pituitary adenoma who suffered symptomatic pituitary apoplexy is reported. Hemorrhaging occurred during endocrine stimulation tests (triple bolus test) in and around the tumor. Both the level of consciousness and the hemiparesis improved after emergency decompression. Histologically the tumor was a chromophobe adenoma of the papillary type with diffuse hemorrhage. Subtotal removal of the tumor was successfully accomplished in a second operation. Routine anterior pituitary stimulation tests have the potential to develop pituitary apoplexy, and we advise that caution should be taken when such tests are planned. The possible mechanism resulting in bleeding is discussed.