This patient has clinical features that suggest prolactinoma. Dopamine suppresses prolactin release in non-breast feeding females, and dopamine agonists, such as bromocriptine and cabergoline, shrink prolactinomas.
Prolactinomas are the most common pituitary adenomas and present with symptoms including amenorrhea, galactorrhea, and infertility. Symptomatic findings in prolactinomas are largely related to the hormonal actions of prolactin. Prolactin stimulates mammary glands to induce galactorrhea and inhibits gonadotropin-releasing hormone (GnRH) secretion, leading to amenorrhea and infertility in females. Larger prolactinomas may compress the optic chiasm and cause bitemporal hemianopsia. Most patients are treated medically and surgical removal is rarely needed.
Mollitch discusses the treatment of prolactinoma in pregnancy. Dopamine agonists are the preferred treatment modality and if symptoms recur secondary to tumor growth, adding dopamine agonists back is usually successful in relieving symptoms and shrinking the tumor.
Leung and Pacaud discuss the clinical diagnosis and management of galactorrhea. Pituitary adenomas are the most common cause of galactorrhea and decision is to treat is often based on severity of symptoms, wishes about fertility and the prolactin level in the serum.
Answer 1: Somatostatin analogs (octreotide) inhibit growth hormone release. They are used in the medical management of acromegaly following the surgical removal of a growth-hormone secreting pituitary adenoma.
Answer 3: Vasopressin analogs (intranasal desmopressin) are used to treat central diabetes insipidus.
Answer 4: Insulin is used to correct hyperglycemia in diabetes mellitus.
Answer 5: There are several classes of serotonin receptor agonists with wide-ranging effects, including migraine treatment (triptans), anxiolytics and anti-depressants (buspirone), hallucinogens (LSD, mescaline), and others. Serotinin receptors agonists are not used in the treatment of prolactinomas.
Molitch ME. Prolactinoma in pregnancy. Best Pract Res Clin Endocrinol Metab. 2011 Dec;25(6):885-96
PMID:22115164 (Link to Abstract)
Leung AK, Pacaud D. Diagnosis and management of galactorrhea. Am Fam Physician. 2004 Aug 1;70(3):543-50
PMID:15317441 (Link to Abstract)
USMLE World Step 1 QBank Question #1917. Copyright © USMLEWorld, LLC 2012