Resolution of possible paradoxical responses of gonadotropins to thyrotropin-releasing hormone with bromocriptine therapy in a patient with follicle-stimulating hormone-secreting pituitary adenoma

We report the effectiveness of bromocriptine therapy in resolving the abnormal responses of plasma FSH and LH to TRH in a 70-year-old male with FSH-secreting pituitary macroadenoma who had unsuccessful transsphenoidal pituitary surgery. In the pre-treatment and post-operative periods, respectively, basal plasma levels of FSH were increased to 88.7 and 65.6 mIU/ml (normal range; 8.5-32.4) but those of plasma LH were normal being 7.0 and 4.1 mIU/ml; (normal range; 4.1 to 14.0). The responses of plasma FSH and LH to LHRH were exaggerated and their paradoxical responses to TRH were highly suggested. During the bromocriptine therapy, the basal level of plasma FSH was normalized and that of plasma LH remained normal. The magnitude of FSH and LH responses to LHRH decreased and their paradoxical responses to TRH were completely resolved.