Makindo Medical Notes

Related Subjects: |Hypoadrenalism |Cushing Disease |Cushing Syndrome |ACTH (Adrenocorticotropic hormone) |Acromegaly and Giantism | Pituitary Adenoma | Pituitary Apoplexy |Diabetes Insipidus (Cranial and Nephrogenic)

A pituitary tumour either haemorrhages or infarcts, seen especially with larger macroadenomas.

About

• Pituitary tumour outgrows its blood supply or is compromised by a fall in blood pressure.

Causes

• Existing Pituitary Adenoma: Pre-existing pituitary tumour, especially macroadenomas.
• Anticoagulation Therapy: Increases risk of haemorrhage within the pituitary gland.
• Major Surgery or Trauma: Physical stress or trauma can precipitate apoplexy.
• Pregnancy: Hormonal changes during pregnancy raise the risk.
• Hypertension: High blood pressure increases likelihood of haemorrhage.
• Radiation Therapy: Radiation treatment as a potential trigger.
• Other Triggers: Dynamic pituitary function testing, stimulation, and infections.

Clinical Presentation

• Sudden severe thunderclap headache, visual loss, ophthalmoplegia, or coma.
• Symptoms may include collapse, delirium, or reduced LOC.
• Hypotension with secondary hypoadrenalism.
• Bitemporal hemianopia, and signs of subarachnoid haemorrhage.

Investigations

• Blood Tests: FBC, U&E, LFT, and clotting profile.
• MRI: The imaging modality of choice to detect haemorrhage or infarction in the pituitary gland.
• CT Scan: Useful acutely but less sensitive than MRI for detecting pituitary abnormalities.
• Endocrine Testing: Serum cortisol, ACTH, TFTs, and PRL to assess pituitary function.
• Visual Field Testing: To evaluate the extent of visual loss or field defects.

Management

• Immediate hormone replacement with IV Hydrocortisone 100-200 mg stat, then every 6 hours IM for acute management.
• Urgent neurosurgical referral for transsphenoidal surgery.
• Coordination between endocrinology and neurosurgery teams is essential.
• Postoperative monitoring of pituitary function and oral Hydrocortisone if needed.

Prognosis

• Prognosis depends on severity of the initial event, speed of diagnosis, and promptness of treatment.
• Visual Recovery: Early surgical decompression improves chances of visual recovery.
• Endocrine Function: Patients may have permanent hypopituitarism, requiring lifelong hormone replacement therapy.

References

• UK Guidelines for the Management of Pituitary Apoplexy