Endocrine Abstracts

We describe a 91 year old woman who presented to hospital with transient loss of consciousness resulting in facial trauma. In the preceding 6 weeks she described 2 similar episodes of loss of consciousness and general malaise. She had a past medical history of pulmonary hypertension secondary to recurrent pulmonary emboli. Relevant medication included furosemide 20 mg od and life-long warfarin.

On examination she had significant orbitofrontal bruising and was noted to be hypotensive with a drop in systolic blood pressure of 50 mmHg on standing. Routine investigations revealed a hypontonic hyponatraemia of 126 mmol/L with a normal serum potassium and urea concentration.

CT brain revealed no intracranial haemorrhage however a mass in the region of the pituitary fossa extending into the suprasellar region was noted. Pituitary function tests performed at 9 am where as follows: cortisol 145 (171–536) nmol/L, LH <0.1 (2.4–13) iu/L, FSH <1.0 (3.5–13) iu/L, Prolactin 6312 (102–496) miu/L, TSH 1.46 (0.3–4.2) mu/L, FT4 7.2 (12–22) pmol/L, FT3 3.0 (3.1–6.8) pmol/L. MRI/MRA revealed bilateral, large (25 mm), partially thrombosed, cavernous carotid aneurysms encroaching on the pituitary fossa. The aneursyms were abutting in the midline such that it was not possible to delineate with certainty the pituitary in between.

The patient was commenced on replacement dose hydrocortisone with rapid resolution of her hyponatraemia and improvement in her constitutional symptoms. Levothyroxine was subsequently added and titrated appropriately. A conservative approach was taken with respect to the carotid aneurysms and she continues to be followed up in endocrine clinic. Her quality of life has significantly improved on hormone replacement allowing her independence to return.

Carotid aneurysms are a rare cause of panhypopituitarism accounting for an estimated 0.17% of cases however the majority of cases are caused by unilateral aneurysms rather than bilateral ones seen in this case.