Assessment of pituitary function in patients with serum prolactin levels greater than 100 ng/ml.
Twelve women with galactorrhea-amenorrhea and prolactin levels greater than 100 ng/ml were evaluated with dynamic pituitary challenge testing. Forty-two per cent of the patients had positive findings on polytomography and subsequent surgical confirmation of a pituitary tumor. Patients with tumors had a delayed elevation of growth hormone (GH) and cortisol following induction of insulin hypoglycemia. Patients had increased thyroid-stimulating hormone levels after injection of thyrotropin-releasing factor, but showed blunting of prolactin secretion. Patients with tumors had decreased basal levels of GH and showed a blunted response to luteinizing hormone-releasing hormone (LRF) stimulation. These patients had normal elevations of follicle-stimulating hormone after LRF challenge. Patients with tumors showed a delay in elevation of GH levels following l-dopa treatment. They also failed to show prolactin suppression following this treatment. There are consistently predictive changes that occur in pituitary functions in the presence of a pituitary tumor. However, absolute prolactin levels and sellar polytomography are more reliable in diagnosing the presence of a pituitary tumor in the patient with galactorrhea-amenorrhea.
D000293:Adolescent; D000328:Adult; D000568:Amenorrhea / Q000503:physiopathology*; D003937:Diagnosis, Differential; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D005687:Galactorrhea / Q000503:physiopathology*; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007775:Lactation Disorders / Q000503:physiopathology*; D007986:Luteinizing Hormone / Q000097:blood; D010901:Pituitary Function Tests; D010902:Pituitary Gland / Q000503:physiopathology*; D010911:Pituitary Neoplasms / Q000175:diagnosis / Q000503:physiopathology*; D011247:Pregnancy; D011388:Prolactin / Q000097:blood*; D013972:Thyrotropin / Q000097:blood
D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin; D013006:Growth Hormone; D006854:Hydrocortisone