The causes of hypopituitarism in the absence of abnormal pituitary imaging.

BACKGROUND Hypopituitarism in the absence of a history of pituitary pathology or abnormal pituitary imaging is rare. AIM To identify the cause of hypopituitarism in individuals in whom pituitary imaging was normal. DESIGN Retrospective analysis of electronic patient record. METHOD A review of the pituitary function in the 506 patients on the Morriston Hospital pituitary database revealed 230 had some degree of hypopituitarism and of these, 21 (9%) had normal pituitary imaging. RESULTS Of this group, six patients had a past medical history of subarachnoid haemorrhage, head injury or meningitis, and mainly suffered from a deficiency of antidiuretic hormone. One patient had a stroke resulting in multiple anterior hormone deficiencies and six individuals had idiopathic cranial diabetes insipidus (DI). Subsequent investigations of the remaining eight patients with normal pituitary imaging revealed that two had neurosarcoidosis both of whom had panhypopituitarism. Four patients had haemochromatosis which resulted in gonadotropin deficiency in two, DI in one and panhypopituitarism in the other. There were two individuals with confirmed hypopituitarism and multiple hormone deficiencies in which no cause could be identified. CONCLUSION These results show that hypopituitarism in the absence of pituitary pathology or an identifiable cause is rare. In patients with multiple anterior pituitary hormone deficiencies haemochromatosis and sarcoidosis should be considered.