Endocrine Abstracts

A 41 year-old gentleman, known case of type 2 diabetes, presented to the emergency department after a witnessed episode of jaw clenching followed by unresponsiveness. The patient was amnesic to the event. He was noted to have a lateral tongue bite. He also reported a similar episode 8 months previously. Initial blood investigations including a random blood glucose were normal. A sulphonylurea induced hypoglycaemia was excluded. Brain imaging by means of a Computed Tomography (CT) Brain showed a large sellar lesion measuring 3.7x4.6x5 cm extending suprasellarly in close proximity to the anterior horn of the left lateral ventricle. This was further evaluated via a Magnetic Resonance (MR) scan of the pituitary which demonstrated a cystic macroadenoma extending suprasellarly compressing the hypothalamus and third ventricle, optic chiasm and encasing the internal carotid arteries. A diagnosis of epilepsy secondary to macroprolactinoma was made. The patient was treated for his epilepsy with sodium valproate and for the prolactinoma via Cabergoline at 0.25 mg twice weekly.

Further investigations included;

• Formal visual field perimetry – surprisingly minimal appreciable bitemporal hemianopia

• Bone Mineral Density – Osteopenia (T score Lumbar spine -1.8, Hip 0.2)

• Baseline echocardiogram – Normal

Within three months the prolactin had decreased to 3841 mIU/lwith a minimal change appreciable on imaging. The patient denied further seizures. Cabergoline was increased to 0.25 mg three times per week. An MR pituitary six months later showed a significant reduction in size with a decrease in the degree of cavernous sinus involvement and no compression of the optic chiasm. Latest prolactin levels have gone down to 680 mIU/l. Despite decrease in prolactin levels testosterone levels remained lower than 10 nmol/l. The patient denied any sexual dysfunction, however in view of osteopenia the patient was started on testosterone undecanoate.