ACTA ENDOCRINOLOGICA (BUC)

Objective. To describe an unusual case of lymphocytic hypophysitis in a man,\r\npresenting with an elevated serum Insulin like growth factor-1(IGF-1) level.\r\nCase report. We report the case of a 27 year old male presenting with a 2 week history\r\nof severe headaches. Magnetic resonance imaging of the head showed an adenoma-like\r\npituitary. The physical examination was normal, laboratory tests revealed secondary\r\nhypothyroidism and hypogonadism along with an elevated IGF-1. Complete\r\ntranssphenoidal resection of the pituitary mass was done. Tissue analysis was diagnostic for\r\nlymphocytic hypophysitis. No evidence of a somatotroph adenoma was found. After surgery\r\nthe patient developed panhypopituitarism and diabetes insipidus.\r\nDiscussion. IGF-1 is a sensitive disease related marker in acromegaly and corresponds\r\nto disease activity. However, it should not be used as the sole marker for diagnosis of\r\ndisease. Inflammatory lesions of the pituitary gland, such as lymphocytic hypophysitis, can\r\nclinically and radiologically mimic tumors of the sellar region.\r\nConclusion. We report an index case of a young male who presented with elevated\r\nserum IGF-1 level in the setting of lymphocytic hypophysitis. This case illustrates the\r\ndilemma associated with reliance on the IGF-1 levels for diagnosis of acromegaly, since an\r\nelevated IGF-1 level in the presence of a pituitary mass may not always be a somatotroph\r\ntumor. We propose the differential diagnosis should also include autoimmune hypophysitis.