Uncontrolled diabetes as a rare presenting cause of pituitary apoplexy

Pituitary apoplexy is a rare endocrine emergency. The extent to which hyperglycaemia is a contributory risk factor in the precipitation of pituitary apoplexy is not known. A 38-year-old man with poorly controlled diabetes presented to the emergency department with sudden onset of nausea and headache with drooping of his right eyelid for about 4 days. On physical examination, he had orthostatic hypotension, ptosis of the right eye, lateral and downward positioning of the eye and absent pupillary reflex. Visual field testing of the left eye revealed superolateral quadrantanopia. MRI of the brain showed pituitary macroadenoma with necrosis. Investigations showed hyperglycaemia, decreased T3, T4 with normal Thyroid stimulating hormone (TSH), low serum Leutinizing hormone (LH), Follicle stimulating hormone (FSH), testosterone and low normal serum prolactin levels. About 21% of non-functioning pituitary adenomas present with apoplexy as was seen in our patient. It is likely that his uncontrolled diabetes precipitated this episode of apoplexy as hyperosmolarity and dehydration, caused by hyperglycaemia can lead to changed pituitary microvascular environment increasing the risk of pituitary infarction.