Primary hypophysitis: clinical-pathological correlations

Abstract

Objective: Primary hypophysitis comprises of three distinct histomorphological entities: lymphocytic, granulomatous and xanthomatous. Clinical features of the three subtypes for diagnostic and treatment strategies have yet not been well characterized. Methods: Endocrine function, visual fields and acuity as well as magnetic resonance imaging characteristics were assessed before and after transphenoidal surgery in the largest series of 31 patients with primary hypophysitis (21 lymphocytic, 6 granulomatous, and 4 xanthomatous cases). Results: Only lymphocytic hypophysitis occurred during pregnancy (30%) and was associated with other autoimmune diseases (24%). Visual fields and acuity abnormalities were not seen in xanthomatous hypophysitis. Lymphocytic and granulomatous hypophysitis most often resulted in severe dysfunction of the adrenal, gonadal and thyroidal axes as well as diabetes insipidus. For patients presenting with xanthomatous hypophysitis most often, mild anterior pituitary axis failure was documented and posterior pituitary involvement was hardly found. The outcome after transphenoidal biopsy was generally favorable. Pre-or postsurgical glucocorticoid treatment was very effective in 75% of the lymphocytic form in reducing the pituitary size. In contrast, glucocorticoid therapy was less effective in granulomatous or xanthomatous hypophysitis. Conclusion: Diffuse destruction of the complete pituitary gland including the infundibulum has to be considered in lymphocytic and granulomatous hypophysitis, whereas in xanthomatous, a circumscribed anterior pituitary lesion leading to compression of the pituitary gland without alteration of the pituitary stalk and optic chiasm can be assumed.

A Radiologic Score to Distinguish Autoimmune Hypophysitis from Nonsecreting Pituitary Adenoma Preoperatively

“…17 MR imaging features more indicative of AH include a symmetric enlargement of the pituitary gland, a thickened nontapering pituitary stalk, and an intact sellar floor. 18,19 In contrast, pituitary macroadenomas are frequently asymmetric, often displacing the infundibulum, and rarely involve the stalk or erode the sellar floor. 20 In addition, macroadenomas appear heterogeneous both before and after contrast medium administration, in direct relationship to their size, though heterogeneity can also occur in AH.…”

Xanthomatous hypophysitis as a cause of cluster headache: a case report

“…Glucocorticoid therapy has been advocated to reduce inflammation and has been temporarily effective in some patients with primary hypophysitis. However, Gutenberg et al (2006) demonstrated that methylprednisolone therapy, administered to one of four patients with XH, did not yield an efficient outcome. Steroid therapy seems to be less effective in XH compared to other kinds of primary hypophysitis…”

Pregnancy and pituitary disorders

“…Maternal mortality during labor is reported in a case (235). The striking temporal association of pregnancy and LyH is not clarified yet, but there are possible explanations, which are as follows: i) pregnancy may unmask a latent pituitary insufficiency and lactotroph hyperplasia may contribute to compression signs caused by LyH, both resulting in earlier diagnosis during gestation (236,237). ii) The increased size of pituitary gland, which may lead to the release of pituitary antigens, may be one of the reasons for autoimmune hypophysitis.…”

“…Several causes have been suggested for hyperprolactinemia: stalk compression or the inflammatory process itself altering the inhibitory effect of dopamine on PRL or the release of hormones into the bloodstream from destructed tissue or PRL-stimulating antibodies (243)(244)(245). Hypoprolactinemia manifested by the inability to lactate after pregnancy may also be seen with LyH (186,237,246).…”

“…Pregnancies may occur following a history of LyH either spontaneously or following ovulation induction (237,(255)(256)(257)(258).…”