Objective: Hypogonadotrophic hypogonadism (HH) is commonly associated with ageing, obesity and type 2 diabetes. The indications for pituitary imaging are controversial, and current guidelines are based on small case series.
Design: Retrospective case series from a secondary/tertiary endocrinology referral centre.
Patients: All men presenting to the Edinburgh Centre for Endocrinology and Diabetes with hypogonadotrophic hypogonadism (testosterone <10 nmol/l and normal prolactin) from 2006 to 2013, in whom pituitary MRI was performed (n = 281). All HH patients referred in 2011 (n = 86) were reviewed to assess differences between those selected for pituitary MRI and those who were not scanned.
Results: Pituitary MRI was normal in 235 men (83·6%), with 24 microadenomas (8·5%), 5 macroadenomas (1·8%) and 1 craniopharyngioma (0·4%) identified. The remaining 16 (5·7%) comprised a range of minor pituitary abnormalities including small cysts and empty sella. All men with abnormal imaging studies had otherwise normal pituitary function. Imaging abnormalities were associated with a significantly lower age at presentation (50 vs 54 years, P = 0·02), but no differences in testosterone or gonadotrophin levels were observed. Current Endocrine Society guidelines would have prompted imaging in only three of six patients with significant pituitary pathology.
Conclusions: Structural pituitary disease is more common in isolated HH than in the general population, and current guidelines do not accurately identify 'at-risk' individuals. Full anterior pituitary function testing has a low yield in patients presenting with hypogonadism. The optimal strategy for determining the need for pituitary imaging remains uncertain.
© 2016 John Wiley & Sons Ltd.