Endocrine Abstracts

Case history: A 57-year-old male with well controlled primary hypertension presented with acute onset severe headache while exercising, associated with nausea and vomiting. He had no visual or other neurological symptoms. The pain settled with analgesics in ED. He reported four transient similar episodes during the preceding 18 months. There were no symptoms suggestive of pituitary or other endocrine dysfunction, including hyperprolactinaemia. Clinical examination was unremarkable with normal cranial nerves, visual field and neurological exam.

Investigations: Routine blood investigations were unremarkable. Urgent unenhanced CT brain imaging revealed possible pituitary apoplexy and CT angiogram excluded a subarachnoid hemorrhage (SAH). Hormone profile revealed significantly elevated serum prolactin (19,730 munit/l), but otherwise normal range values, though ACTH and cortisol levels were sampled post hydrocortisone administration. MRI pituitary and MRA showed an invasive pituitary macroadenoma with intra-tumoural fluid levels consistent with recent hemorrhage/necrosis. The macroadenoma partly encases the cavernous-left internal carotid artery (ICA), and completely surrounds a 9mm aneurysm arising from the ICA side-wall just proximal to the level of the ophthalmic artery origin. There was no appreciable local mass effect on the optic nerves or chiasm.

Results and Treatment: The patient was commenced on hydrocortisone, and transferred to the local neurosurgical centre for further imaging and management. The apoplexy was managed conservatively and endovascular treatment of the cavernous ICA (C-ICAA) aneurysm was prioritized before medical treatment of the macroprolactinoma.

Conclusions and points for discussion: We present a case of pituitary apoplexy in a macroprolactinoma whose management was complicated by the co-existence of a C-ICAA. C-ICAA rarely rupture because of the surrounding bony and dural structures but the risk is observed to be increased when this protection is eroded by invasive pituitary tumour. There was no appreciable evidence to suggest previous bleeding or contained rupture, though the recurrent prior headache episodes may reflect micro bleeds, and the risk of re-bleed in the aneurysm is potentially life threatening. Commencement of dopamine agonist (DA) therapy could cause rapid shrinkage of the tumour with possible de-tamponade effect if there is a micro bleed. DA therapy and cystic degeneration within a pituitary tumour are both recognized predisposing factors in pituitary apoplexy. Caution is needed when initiating DA therapy in this case and definitive management of the C-ICAA was prioritized first.