Dysfunction of dopaminergic regulation of prolactin in patients with functioning and nonfunctioning pituitary adenomas and craniopharyngiomas

The response to domperidone (a dopamine blocking agent) of serum prolactin (PRL) levels was compared in 3 patients with amenorrhea-galactorrhea without evidence of a pituitary tumor, 23 patients with prolactinomas (10 cases with histologic confirmation), 7 patients with histologically verified large nonfunctioning pituitary adenomas with normal or moderately elevated basal PRL levels, and 6 patients with histologically verified craniopharyngiomas (3 with normal basal PRL levels and 3 with elevated PRL levels). The response was compared with that of 10 patients with postpartum hyperprolactinemia and 14 normal women. Ten milligrams of intravenous domperidone induced a rapid rise in PRL that was maximal at 30 to 45 minutes in normal, postpartum, and amenorrhea-galactorrhea patients who had no sign of tumor. In contrast, domperidone failed to induce significant changes in PRL in cases of prolactinoma, nonfunctioning pituitary adenomas, and craniopharyngioma with or without elevated basal PRL levels. The results suggest that dopaminergic control on PRL secretion was impaired in all tumor cases. The mechanisms of this abnormal dopaminergic control, however, may be different. Whereas dopamine control in cases of prolactinoma is altered at the level of pituitary dopamine receptors, alternative explanations must be found for those tumors with normal basal PRL levels and lack of response to domperidone.     

Galactorrhea and pituitary tumors in postpill and non-postpill secondary amenorrhea.

One hundred sixty-seven women with secondary amenorrhea were observed from six months to four years. In 66 patients, the amenorrhea followed the discontinuation of oral contraceptives (postpill) while in the remaining 101 the amenorrhea was not temporally pill related (non-postpill). Galactorrhea was present in 43 (65%) of those with postpill amenorrhea and in 32 (32%) of those with non-postpill amenorrhea (p less than 0.001). Tomography of the sella turcica was performed in the 75 women with galactorrhea and in the 35 without galactorrhea who did not have withdrawal uterine bleeding following progesterone administration and who had low or normal serum follicle-stimulating hormone levels (hypothalamic-pituitary failure). Forty of the 75 patients with amenorrhea and galactorrhea had radiographic evidence of a pituitary tumor whereas only eight of 35 patients with hypothalamic-pituitary failure without galactorrhea had an abnormal sella turcica (p less than 0.01). The incidence of radiographic abnormalities in those with galactorrhea was similar in both the postpill and non-postpill groups.     

The effect of contraceptive steroids on hypothalamic-pituitary function.

A study was performed to obtain additional information about the effects of oral contraceptives on pituitary function. A sequential pituitary stimulation test (SST) was used to study normal control women who then received either a combination pill with 50 mug of ethinyl estradiol or an injectable or oral progestin for three weeks, after which the test was repeated. The same test was also performed on five long-term oral contraceptive users. The SST consists of measurement of growth hormone (GH), thyroid-stimulating hormone (TSH), prolactin (PRL), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) at frequent intervals after stimulation by hypoglycemia, thyrotropin-releasing hormone, and gonadotropin-releasing hormone. GH and TSH release following stimulation were unaffected by the use of contraceptive steroids, while PRL release was increased by both the combination pill and the progestin alone. LH and FSH release was decreased in the three short-term and most of the long-term users of the combination pills but was not decreased in two of the long-term users as well as in those receiving the progestin alone. These results indicate that the combination oral contraceptives have a direct effect upon the pituitary gland, causing an increase in prolactin release and a decrease in gonadotropin release. This effect varies among individuals receiving the same formulation and may be related to the development of syndrome of postpill amenorrhea-galactorrhea.     

Spontaneous pregnancy in women with a prolactin-producing pituitary adenoma

The occurrence of spontaneous pregnancy in patients with amenorrhea-galactorrhea, hyperprolactinemia, and radiographic evidence of a pituitary tumor is unusual. We present here two patients who conceived spontaneously. One had an uneventful pregnancy. Following delivery, transsphenoidal pituitary surgery was performed, confirming the presence of a prolactin-producing adenoma. The second patient had an early pregnancy termination (at 12 weeks of gestation). These patients provide evidence that ovulation and pregnancy can occur in spite of elevated prolactin levels.     

Hyperprolactinemia associated with clinically silent adenomas: endocrinologic and pathologic studies; a report of two cases

Pituitary adenomas containing adrenocorticotropic hormone (ACTH) in one case, and ACTH, beta-lipotropin, and beta-endorphin in the other, were demonstrated in two patients who had amenorrhea-galactorrhea and hyperprolactinemia with no manifestation of Cushing's disease. Neither adenoma contained prolactin (PRL). Initial bromocriptine therapy resulted in cessation of amenorrhea-galactorrhea and normalization of PRL levels. However, there was radiologic evidence of tumor enlargement in both patients. After pituitary adenomectomy, the two patients resumed regular menses and normal PRL dynamics. These patients illustrate the need for bromocriptine therapy for possible enlargement of their pituitary adenomas. The diagnosis of silent corticotroph adenoma should be kept in mind.     

Clinical history and outcome of 59 patients with idiopathic hyperprolactinemia.

OBJECTIVE: To investigate the clinical course of hyperprolactinemia without demonstrable cause. DESIGN: Prospective study of all patients with idiopathic hyperprolactinemia first seen between 1974 and 1985. SETTING: Outpatient Department of University Hospital. PATIENTS: Fifty-nine patients followed for 6 to 190 months (median 78 months). Medical treatment given only in case of anovulatory infertility or hypogonadism. OUTCOME MEASURES: Development of pituitary (micro)prolactinoma, prolactin (PRL) levels, and clinical signs of menstrual dysfunction. RESULTS: With exception of one woman in whom it probably had been missed by hypocycloidal tomography, no demonstrable prolactinoma developed. Prolactin levels rose in two patients, one using oral contraceptives and the other with prolactinoma. At the end of follow-up, 15 of 16 patients using a dopaminergic drug had a normal cycle; 13 had normal final PRL levels. From the 43 patients off medication, 28 (66%) had normal PRL levels and 23 (54%) had a normal cycle. There were no significant differences between women who had and had not been pregnant. Dopaminergic medication had no appreciable influence on the course of the disease. CONCLUSION: In idiopathic hyperprolactinemia, progression to pituitary prolactinoma seldom, if ever, occurs. There is a high tendency to spontaneous cure, and pregnancy or medication have no apparent effect. Frequent pituitary imaging was found to be not necessary in our patient population. It may best be reserved for situations in which the PRL level in symptomatic hyperprolactinemia is inconsistent with pituitary imaging results.     

Primary amenorrhea-galactorrhea with hyperprolactinemia and huge pituitary enlargement in juvenile primary hypothyroidism.

We report a girl with juvenile primary hypothyroidism revealed by growth retardation and a syndrome of primary amenorrhea-galactorrhea with hyperprolactinemia and suprasellar pituitary enlargement. Resolution of the pituitary enlargement and the amenorrhea-galactorrhea syndrome occurred after thyroid hormone replacement. No similar observation has been reported earlier in juvenile hypothyroidism.     

Adult-onset amenorrhea: a study of 262 patients

A series of 262 patients with amenorrhea of adult onset are reported. Hypothalamic suppression followed by inappropriate positive feedback, and then hyperprolactinemia and ovarian failure are the most frequently encountered etiologies. Other etiologies are diverse and numerically less frequent. Amenorrhea after use of oral contraceptives, or postpill amenorrhea, occurred in 77 (29%) of all patients. The average age of presentation, prior menstrual history, associated morbidity, and subsequent reproductive potential of each diagnostic group are reported. Adult-onset amenorrhea has a less significant impact on future wellbeing than was reported for a similar-sized group of patients whose amenorrhea developed as a result of pubertal aberrancy.     

Coexistent empty sella and prolactin-secreting microadenoma

The empty sella turcica may be found in people with no antecedent history of intracranial disease, as well as in those with known pituitary pathology or following therapy to the pituitary gland. We have evaluated 3 women with galactorrhea and hyperprolactinemia, 2 of whom had amenorrhea. Each had an empty sella. In all cases polytomograms demonstrated asymmetry of the sella floor with focal bony erosion, conventional pneumoencephalography showed intrasellar air, and polytomographic pneumoencephalography confirmed air limited to one side of the pituitary fossa with tumor and/or residual normal tissue on the opposite side. In 2 patients who had extensive endocrine evaluation, pituitary function was normal with the exception of hyperprolactinemia. Transsphenoidal excision of microadenomas resulted in postoperative normalization of the serum prolactin concentration and resumption of regular menses in the previously amenorrheic women.     

Are there two types of postpill anovulation?

Anovulation, indicated by requiring treatment with clomiphene or gonadotropins to conceive, was studied in a cohort of 16,583 women interviewed postpartum. There were 2,853 former oral contraceptive users, and 2.2% of them reported anovulation, compared with 2.7% of controls. Among primigravidas, the rates were 4.2% and 4.4% in pill users and controls, respectively. A statistically significant excess of anovulation was reported by former pill users who had been underweight in relation to their height at the time of conception. Independently of pill use, the condition tended to be associated with obesity. Data from this and previous studies suggest that there may be two distinct entities of postpill anovulation: the first, identical with spontaneous secondary anovulation; the second, occurring in slender women who have used oral contraceptives. These findings need confirmation from prospective studies using standard diagnostic criteria.     

The effects of pregnancy on patients with hyperprolactinemia

Seventy women with amenorrhea with or without galactorrhea associated with high serum prolactin levels and radiologic evidence of pituitary tumors were treated with transsphenoidal tumor resection. The prolactin level was measured in 29 patients before pregnancy, at 3 months post partum or cessation of lactation, and at 6-month intervals thereafter. The results were compared to those of 18 patients who had hyperprolactinemia but no demonstrable radiologic evidence of a pituitary tumor and who responded to bromocriptine and conceived. Our investigations showed that operation resulted in normalization of serum prolactin levels in 74% of patients. Forty of the 49 patients less than 36 years old conceived (80%). Five of 29 patients who were studied before and after operation as well as after delivery showed an increase in serum prolactin levels post partum and persistent amenorrhea suggesting recurrence. Six of the 18 patients who became pregnant after bromocriptine also showed a significant rise in serum prolactin levels above the treatment level. None of the patients in the two groups developed visual changes or symptoms or radiologic changes during pregnancy. These results showed that transsphenoidal operation has a high incidence of success, but some patients may show a rise of serum prolactin levels and persistent amenorrhea after pregnancy or passage of time, suggesting recurrence. Some patients who become pregnant after bromocriptine therapy may have further rises in prolactin greater than pretreatment levels. Follow-up of these patients is indicated.     

Oral contraceptive exposure of amenorrheic women with and without prolactinomas

The purpose of this study was to determine the extent of oral contraceptive (OC) exposure of women with secondary amenorrhea of hypothalamic-pituitary etiology. In 93 of 126 women with secondary amenorrhea sufficient data were obtained regarding menstrual history and OC exposure: 26 patients had evidence of a prolactinoma, an additional 26 patients had idiopathic hyperprolactinemia without evidence of a pituitary tumor, and 41 had "pure" dysfunction hypothalamic-pituitary amenorrhea. After stratification by age at diagnosis and parity the estimated odds ratio for past oral contraceptive usage showed no differences among the three groups (odds ratios between 0.74 and 1.48). Using the chi-square test the proportion of subjects who had regular menses before oral contraceptive intake and developed anovulation immediately after discontinuance ("post pill amenorrhea") in the three groups also showed no difference (x2 = 0.60, P = 0.74). These data indicate that non-ovulatory patients are likely to have been exposed to OC, and do not indicate that patients with prolactinomas differ in the extent of their OC exposure from other specified groups of patients with secondary.     

Bromocryptine therapy in cases of amenorrhea-galactorrhea

Of 28 patients presenting with amenorrhea-galactorrhea, pituitary tumors were confirmed in eight. Six patients had occult hypothyroidism and the rest had an endocrine profile suggestive of pituitary tumor or of an idiopathic etiology. Treatment with bromocryptine resulted in suppression of the inappropriate lactation and restoration of regular menstrual function. In five cases, however, the galactorrhea was only diminished and in four of these cases, normal ovarian function did not return. Of the 19 patients that were seeking fertility and continued the medication for at least 20 days, nine pregnancies resulted. A similar response to bromocryptine was observed regardless of the underlying cause of the amenorrhea-galactorrhea.     

Etiology, clinical features and prognosis in secondary amenorrhea.

A clinical investigation of 356 patients with secondary amenorrhea revealed that 95% of patients with postpill amenorrhea and 56% of patients with anorexia nervosa recovered in 6 years. The corresponding recovery rates for patients with psychogenic amenorrhea and amenorrhea following self-induced weight loss were 72% for both groups, and in patients with the amenorrhea-galactorrhea syndrome and idiophatic functional amenorrhea the recovery rates at 6 years were 64 and 61% respectively. Unlike the other groups with functional amenorrhea, patients with the amenorrhea-galactorrhea syndrome had impaired ovarian responsiveness to exogenous gonadotropins. Bromocriptine treatment resulted in disappearance of the galactorrhea and restoration of the menses and/or ovulation in nine of 18 patients; of these three became pregnant. The effect of bromocriptine did not persist for long after treatment ceased, and permanent recovery was recorded only in four patients. The group with functional amenorrhea included 34 patients who wished to become pregnant. Gonadotropin treatment was successful in 20 patients, clomiphene-hCG in two, tamoxifen in two, bromocriptine in two, and combined bromocriptine and clomiphene in one. Thus, the overall pregnancy rate in patients with functional amenorrhea was 79%. The groups with ovarian amenorrhea inclutients with assumed ovarian failure responded to large doses of exogenous gonadotropins by ovulation and three became pregnant. Ovarian wedge resection was ineffective in all five cases with polycystic ovaries, but two patients became pregnant after treatment with clomiphene and chorionic gonadotropin, and one with exogenous gonadotropins.     

A study of postpill amenorrhea

Levels of follicle-stimulating hormone, luteinizing hormone and prolactin were evaluated in 52 cases of postpill amenorrhea at the Institute of Post Graduate Medical Education and Research, Calcutta, India. All 52 patients had experienced amenorrhea for one year since discontinuation of oral contraceptive therapy. The incidence of postpill amenorrhea was much higher in patients with histories of oligomenorrhea or irregular menstrual periods. No relationship was seen between the number of cycles of pills used and the incidence of postpill amenorrhea. The ratio of luteinizing hormone to follicle-stimulating hormone in all cases exceeded unity, indicating that postpill amenorrhea is a type of functional secondary amenorrhea.     

Amenorrhea following the administration of oral contraceptives

It is estimated that about 2.2% of women experience amenorrhea and anovulatory cycles after discontinuing use of oral contraceptives (OCs), although exact figures are lacking due to differences of definition and problems of diagnosis. Several possible mechanisms to explain the occurrence of postpill amenorrhea have been suggested, including endometrial atrophy and fibrosis, changes in the ovaries similar to those found in Stein-Levanthal syndrome, hypothalamic disorder, late menarche, irregular cycles, and periods of amenorrhea before or during OC use. Previous pregnancies, duration of pill use, and formulation utilized are apparently not related to occurrence of post-pill amenorrhea. Clinical diagnosis requires detection of ovulation by means of basal body temperature, cervical mucus changes, and vaginal smears. If amenorrhea persists after administration of a progestagen to induce bleeding, more complete examinations must be done to exclude pituitary tumor, Cushing's syndrome, thyroid problems, and possible precocious menopause or anorexia nervosa. X-rays, administration of thyroid or suprarenal hormones, gonadotropins, or estrogens, an endometrial biopsy, or laparoscopy may be necessary. Generally all test values are normal except that levels of estrogens, follicle stimulating hormone, and luteinizing hormone are usually reduced. Treatment of post-pill amenorrhea can take various forms. About 5% of cases appear to resolve spontaneouusly; efforts should therefore be made to detect ovulation through basal body temperature, cervical mucus and vaginal smears. Corticosteroids including prednisone and dexametasone may administrered, or if estrogen levels are low and the patient fails to respond to progestagens with withdrawal bleeding, clomiphene may be used. Human menopausal gonadotropin or human chorionic gonadotropin can be in patients with low estrogen levels who do not respond to clomiphene. Ergocriptine derivatives may be used in cases with associated galactorrhea due to basal hyperprolactinemia. Palliative treatment with OCs may be used in patients who wish to avoid pregnancy. The prognosis is always poor in the presence of galactorrhea or if progestagen administration is not followed by withdrawal bleeding or estrogen levels are low. Treatment is usually futile in cases of polycystic ovaries that have sclerosed. The most significant feature of such amenorrhea is its role in infertility. If the patient wishes to become pregnant after some period of OC use, it is advisable to interrupt treatment periodically until 1-2 normal menstrual cycles have reappeared, especially in young patients who had irregular cycles before initiating hormonal contraception.     

Detection, evaluation, and treatment of pituitary microadenomas in patients with galactorrhea and amenorrhea

Over a period of two and a half years, 34 women with galactorrhea or amenorrhea, all with an abnormal sellar polytomogram, underwent transsphenoidal microsurgical exploration of the sella. Eighteen women and microadenomas (less than or equal to 1 cm. in diameter), seven had macroadenomas (greater than than 1 cm. in diameter), and five had unidentified lesions. Only one women had a normal pituitary gland. Three women had cryosurgery without biopsy. Preoperatively, hyperprolactinemia occurred in 24 of 25 women with adenomas and two of five with nonadenomatous lesions. There were no operative deaths. Significant morbidity occurred in only three patients, none of whom had microadenomas. Postoperatively, menses resumed in 16 of the 17 women with microadenomas and in two of the seven with macroadenomas who presented with amenorrhea. Galactorrhea disappeared in 15 of the 17 women with microadenomas and in four of the seven with macroadenomas who presented with galactorrhea. In five patients with unidentified lesions, a return of menses occurred in two of four with previous amenorrhea, and galactorrhea abated in two of three who presented with lactation. We conclude that sellar polytomography in women with hyperprolactinemia is a useful technique technique for the diagnosis of pituitary adenomas, a lesion which may occur more frequently than previously realized. In addition, transsphenoidal microresection of microadenomas is safe and effective.     

Hyperprolactinemia: comparison of thyrotropic-releasing hormone and tomography

A group of 95 women with unexplained hyperprolactinemia (over 20 ng/mL) underwent radiologic examination of the sella turcica with hypocycloidal polytomography (N = 58), computed axial tomography (N = 8), or both (N = 29). All patients also underwent a thyrotropin-releasing hormone (TRH) stimulation test, with serum prolactin (PRL) measurement before and 20 and 30 minutes after a 500-micrograms intravenous bolus of TRH. Their PRL responses were compared with those of two control groups, nine normal women in the follicular phase of the menstrual cycle, and 13 women in the first five months of gestation with pregnancy-related hyperprolactinemia. Both control groups exhibited PRL increases with 95% confidence limits at least 200% above baseline levels. In all, 12 patients from the study group also had a normal PRL response (more than a 200% increase) to TRH, and none of these women had tomographic findings consistent with a pituitary tumor. The remaining 83 women all had diminished or absent PRL increases after TRH administration; 46 (55%) of these patients had radiographic evidence of an adenoma, whereas 37 (45%) had no clear signs of a tumor on either polytomography or computed axial tomography. No patient with a baseline PRL level in excess of 60 ng/mL had a normal PRL response to TRH. The results of the study indicate that 1) in patients with PRL between 20 and 60 ng/mL, a normal TRH test can be relied upon to avoid the expense and radiation of tomography (computed axial tomography or polytomography), 2) there is no benefit to be obtained in performing a TRH test in patients with a baseline PRL level over 60 ng/mL, and 3) about 45% of patients with hyperprolactinemia and an abnormal TRH test have a normal computed tomography or polytomography. These patients may have a small adenoma, and thus warrant closer follow-up than patients with a normal TRH test.     

Management of patients with hyperprolactinemia and normal or abnormal tomograms

Forty women with hyperprolactinemia with and without radiologic evidence of prolactin-secreting pituitary adenoma were prospectively treated with bromocriptine. On the basis of tomographic studies, the patients were divided into either a microadenoma group (N = 19) or no adenoma group (N = 21). Both groups had similar distributions as to obstetric history, menstrual abnormalities, levels of baseline serum luteinizing hormone, follicle-stimulating hormone, and thyrotropin. Patients in the adenoma group had significantly higher (p less than 0.001) baseline serum prolactin levels (173 +/- 4.4 ng/ml) than those of patients without adenoma (61.1 +/- 4.5 ng/ml). Patients without an adenoma required significantly less bromocriptine (5 to 7.5 mg) (p less than 0.005) to normalize serum prolactin or establish a pregnancy than did those who had an adenoma (5 to 20 mg). Similarly, patients with adenoma resumed ovulatory cycles (8.7 +/- 1.2 versus 5.7 +/- 0.06 weeks), had their galactorrhea disappear (11.3 +/- 2.1 versus 5.6 +/- 1.1 weeks), and become pregnant (16.2 +/- 2.5 versus 9.8 +/- 1.5 weeks) in a significantly longer time (p less than 0.01) than did those who had no adenomas. There was no significant difference in the pregnancy rate between the groups, and the overall rate was 86% of 28 patients desiring pregnancy. No complications were observed during pregnancy. The conclusion is that both patients with and those without radiologic evidence of a prolactin-secreting pituitary adenoma can be safely treated with bromocriptine. In addition, the resumption of ovulatory cycles is more important than the absolute normalization of serum prolactin.     

An endocrinological study of hyperprolactinemia and its treatment (author's transl)

Twenty-six cases of women with pituitary adenoma and seven cases of women with functional hyperprolactinemia were studied to evaluate the effects of neurosurgery and Bromocriptine treatment. In the patients with pituitary adenoma, the mean serum PRL level was significantly higher than that in the functional cases. Among the patients with pituitary adenoma, the serum PRL levels were roughly correlated to the size of the tumors. Basal serum LH, FSH and 17 beta-estradiol levels were lower in the patients with pituitary macroadenoma than in those with microadenoma. Neurosurgery was performed on fourteen patients of pituitary adenoma. Of ten cases with visual disturbance, it was necessary to use Bromocriptine to reduce the serum PRL to the normal level after operation. In the treatment of sixteen patients with microadenoma, Bromocriptine alone was used for eight of them and surgery was performed on four. As a result, there was a significant lowering of the serum PRL level and induction of regular menses in ten patients. Regular menses were induced by means of Bromocriptine treatment in all of the patients with functional hyperprolactinemia. Our data indicate that neurosurgery, either selective or combined with Bromocriptine, can normalize PRL levels and induce regular menses in patients with hyperprolactinemia.