Urgent considerations

See Differentials for more details

Pituitary apoplexy

A prolactinoma may rarely present as pituitary apoplexy, a clinical syndrome caused by infarction or haemorrhage (with or without infarction) of a pituitary adenoma. When this occurs, a large proportion of the adenoma, or even the entire tumour, becomes a haemorrhagic mass that expands rapidly and compresses neighbouring structures.[42][43] This mass appears as a hyperdense lesion on T1- and T2-weighted magnetic resonance imaging.

The peak incidence of pituitary apoplexy is in the fifth decade of life, although it can affect all age groups. It most commonly occurs in patients with large macroadenomas, but there is evidence that tumours of any size can manifest with haemorrhage and apoplexy. In approximately 80% of cases, pituitary apoplexy is the presenting symptom of an undiagnosed pituitary adenoma.[44]

Predisposing factors

  • Reduced blood flow in the pituitary gland (due to hypotension, surgery, or haemodialysis).

  • Acute increase of pituitary blood flow (due to diabetes mellitus or chronic systemic hypertension).

  • Stimulation of the pituitary gland through increased oestrogen states (due to oestrogen administration or pregnancy), dynamic pituitary tests (gonadotrophin-releasing hormone, thyrotropin-releasing hormone), or bromocriptine treatment.

  • Anticoagulated state (e.g., by anticoagulant drug or thrombolytic agent administration or due to thrombocytopenia).[44]

Pathophysiology

  • Rapid tumour expansion causes the tumour to outgrow its own blood supply leading to ischaemic necrosis.

  • Compression of the pituitary portal blood supply against the diaphragma sellae.

  • Vasculopathy or fragility of the tumour blood vessels.[44]

Clinical features

  • The degree of clinical manifestation ranges from an asymptomatic state (diagnosed only retrospectively) to a sudden onset of headache, visual loss, nausea and vomiting, cranial nerve palsies, hemiparesis, and impairment of pituitary function.

  • If the haemorrhage breaks into the subarachnoid space, pituitary apoplexy can be accompanied by meningeal irritation, neck stiffness, and photophobia.

  • Misdiagnosed or untreated pituitary apoplexy may result in severe hypotension and shock due to secondary adrenal deficiency (as a result of adrenocorticotrophic hormone deficiency), irreversible visual loss, or diplopia.[42][43][45]

Management

  • Supportive therapy with intravenous fluids and corticosteroids (e.g., dexamethasone) results in clinical improvement in many patients.

  • Transsphenoidal surgical decompression of the tumour can be undertaken in cases where conservative treatment is unsuccessful or in the presence of progressive vision loss and/or cranial neuropathy. This surgery should ideally be done within 24 to 48 hours of onset.

  • Long-term follow-up to treat any residual tumour and/or pituitary dysfunction is required.[42][43][45][46]

Use of this content is subject to our disclaimer