PMC5338910_01
Sagittal post contrast T1 weighted fat saturated image showing an enlarged, heterogeneously enhancing pituitary gland. A small cyst-like component seen centrally within the gland resolved on subsequent imaging.
gr1.jpg
PMC5338910_01_gr1.jpg
fig0005
Other differentials included metastasis, lymphoma, hypophysitis or rarely, vasculitis (Fig. 1).
a & b: Sagittal (a) and coronal (b) post contrast T1 weighted fat saturated images show interval increase in size of the pituitary gland resulting in superior displacement of the optic chiasm (white arrow).
gr2.jpg
PMC5338910_01_gr2.jpg
fig0010
Despite 6 months of conservative management with monthly IV cyclophosphamide, polydipsia increased to 8 L/day and repeat contrast MRI showed interval increase in pituitary gland size, resulting in mild superior displacement of the optic chiasm (Fig. 2).
Haematoxylin and eosin stained sections at x400 magnification of mature pituitary sections showing a necrotising inflammatory process, in association with histiocytes and multinucleated giant cells.
gr3.jpg
PMC5338910_01_gr3.jpg
fig0015
Histology revealed necrotising inflammation within the anterior pituitary associated with histiocytes and scattered multinucleated giant cells (Fig. 3).