Pituitary Apoplexy

In pituitary apoplexy, the patient presents with:

• Abrupt severe headache
• Progressive visual loss

Later, there may signs of pituitary insufficiency.

Causes

Pituitary apoplexy is associated with haemorrhage into an enlarged pituitary gland. This most commonly occurs in patients with a pituitary adenoma. Acute haemorrhage results in sudden, further enlargement of the pituitary, and the associated features of a compressive space-occupying lesion.

Presentation

In 95% of cases, patients present with acute headache. Most cases occur in middle-aged patients and it is more common in men.

Compression of the cavernous sinus causes compression of the III, IV and VI cranial nerves as they traverse the sinus. This results in diplopia.

Diagnosis

This requires a high index of suspicion. The combination of headache and ophthalmoplegia is sufficient to consider the diagnosis, and any haemorrhage should be detectable on CT scanning.

Learning bite

Sheehans syndrome is a rare complication of pregnancy where the pituitary gland undergoes ischaemic necrosis following significant peri-and post-partum haemorrhage. Whilst most women will present subacutely with features of hypopituitarism (e.g. difficulties with lactation, features of hypothyroidism), rarely they can present acutely post-partum with electrolyte disturbances such as hyponatraemia due to disordered ADH production.