Pituitary hyperplasia

Radiopaedia • CC-by-nc-sa 3.0 • de

Pituitary hyperplasia refers to the diffuse pituitary enlargement that can be physiological in young menstruating females or pregnant/lactating women or, less commonly, secondary to end-organ failure.

Pathology

The upper limit of normal pituitary height varies with age and gender :

  • infants, children: 6 mm
  • males and postmenopausal women: 8 mm
  • young menstruating females: 10 mm
  • pregnant/lactating women: 12 mm

Non-physiologic pituitary hyperplasia is commonly caused by an end-organ failure such as hypothyroidism , Addison disease and neuroendocrine tumors . Medications such as estrogen, GnRH analogs and antipsychotics can cause or exacerbate pituitary hyperplasia .

Radiographic features

The pituitary gland can be assessed both by CT and MRI dedicated protocols, which can show the following:

  • enlarged homogeneously enhancing pituitary gland with a convex superior margin
  • size : >10 mm up to 15 mm
  • maybe globular/nodular, mimicking pituitary adenoma

Treatment and prognosis

Only surveillance is suggested until reversal of the underlying pathological condition as pituitary hyperplasia rarely progresses .

 Differential diagnosis