Hyperprolactinaemia in males with and without pituitary macroadenomas

Overview of infertility

Having a child is an innate trait in animals, including humans, and is required for the continued existence of all animal species. Therefore, for most women, the inability to conceive or to do so in a timely fashion - termed infertility - to enable the continuation of the family line can be emotionally distressing. The definition of infertility is controversial because of its separation into primary and secondary. This is further complicated by the loosely used term subfertility, which relates to couples who have reduced ability because they take longer than the natural time to conceive, as opposed to those who are infertile and are entirely unable to conceive after 6 to 12 months, depending on age. Infertility evaluation requires a thorough male and female history, physical examination of both partners, and targeted investigation to determine the cause of infertility in a particular couple. Various treatments apply to infertile couples depending on the age of the female partner, the results of investigations, the reason for infertility, the presence of inheritance of abnormal genes, the pregnancy rates the couple is happy with, the resources available, how desperate the couple is to achieve a live birth, and how much they want to commit to treatment. Infertility treatment could include counseling and expectant management only, intrauterine insemination in a natural or stimulated cycle, and IVF and or ICSI. Men with azoospermia will need surgical options to retrieve sperm for IVF/ ICSI, but rarely for IUI. This review overviews infertility's etiology, diagnosis, investigations, and treatment.

Experience in the Treatment of Male Prolactinomas: A Single-Center, 10-Year Retrospective Study

INTRODUCTION

Male prolactinomas are uncommon and typically macroadenomas with difficult treatment and management. The purpose of this study was to summarize the treatment and management experiences of 254 male prolactinoma patients at a single center.

METHODS

This was a 10-year retrospective study conducted at a single center. A total of 254 male prolactinoma patients were included. Clinical data for all subjects were collected using an electronic medical record system.

RESULTS

A total of 254 male patients with prolactinoma were studied. Their median age at onset was 28.8 years, and median disease duration was 28.5 months. The median PRL levels were 582.0 ng/mL at diagnosis. Their median maximum tumor diameter was 23.0 mm, with macroadenoma accounting for the majority (76.7%). After treatment, the biochemical remission rate with monotherapy was 36.6%, but significantly increased to 60.6% with multidisciplinary treatment (p < 0.001). Knosp 0-2 patients had significantly higher rates of biochemical remission compared to Knosp 3-4 (all p < 0.05). In addition, the maximum diameter of adenoma (B = -0.110, p = 0.008) and cavernous sinus invasion (B = -1.741, p = 0.023) were negatively correlated with postoperative biochemical remission. The maximum diameter of the adenoma (B = - 0.131, p < 0.001) was a negative correlation factor, while treatment duration (B = 0.034, p = 0.002) was a positive correlation factor for biochemical response to medication.

CONCLUSION

Male prolactinoma has a low biochemical remission rate when treated alone, but multitherapy can improve it even more. Surgery may also be considered for male prolactinoma with a micro, and noninvasive tumor after a thorough evaluation.

INTRODUCTION

Male prolactinomas are uncommon and typically macroadenomas with difficult treatment and management. The purpose of this study was to summarize the treatment and management experiences of 254 male prolactinoma patients at a single center.

METHODS

This was a 10-year retrospective study conducted at a single center. A total of 254 male prolactinoma patients were included. Clinical data for all subjects were collected using an electronic medical record system.

RESULTS

A total of 254 male patients with prolactinoma were studied. Their median age at onset was 28.8 years, and median disease duration was 28.5 months. The median PRL levels were 582.0 ng/mL at diagnosis. Their median maximum tumor diameter was 23.0 mm, with macroadenoma accounting for the majority (76.7%). After treatment, the biochemical remission rate with monotherapy was 36.6%, but significantly increased to 60.6% with multidisciplinary treatment (p < 0.001). Knosp 0-2 patients had significantly higher rates of biochemical remission compared to Knosp 3-4 (all p < 0.05). In addition, the maximum diameter of adenoma (B = -0.110, p = 0.008) and cavernous sinus invasion (B = -1.741, p = 0.023) were negatively correlated with postoperative biochemical remission. The maximum diameter of the adenoma (B = - 0.131, p < 0.001) was a negative correlation factor, while treatment duration (B = 0.034, p = 0.002) was a positive correlation factor for biochemical response to medication.

CONCLUSION

Male prolactinoma has a low biochemical remission rate when treated alone, but multitherapy can improve it even more. Surgery may also be considered for male prolactinoma with a micro, and noninvasive tumor after a thorough evaluation.

Hyperprolactinemia and male sexual function: focus on erectile dysfunction and sexual desire

The present paper aims to analyze and discuss the available evidence supporting the relationship between male sexual function and elevated prolactin (PRL) levels (HPRL). Two different sources of data were analyzed. Clinical data were derived from a series of patients seeking medical care for sexual dysfunction at our Unit. Out of 418 studies, 25 papers were used with a meta-analytic approach to evaluate the overall prevalence of HPRL in patients with erectile dysfunction (ED) and to study the influence of HPRL and its treatment on male sexual function. Among 4215 patients (mean age 51.6 ± 13.1 years) consulting for sexual dysfunction at our Unit, 176 (4.2%) showed PRL levels above the normal range. Meta-analytic data showed that HPRL is a rare condition among patients with ED (2 [1;3]%). Either clinical and meta-analytic data confirm a stepwise negative influence of PRL on male sexual desire (S = 0.00004 [0.00003; 0.00006]; I = -0.58915 [-0.78438; -0.39392]; both p < 0.0001 from meta-regression analysis). Normalization of PRL levels is able to improve libido. The role of HPRL in ED remains inconclusive. Data from a meta-analytic approach showed that either HPRL or reduced T levels were independently associated with ED rates. The normalization of PRL levels only partially restored ED. HPRL did not significantly contribute to ED severity, in our clinical setting. In conclusion, treating HPRL can restore normal sexual desire, whereas its effect on erection is limited.

Prolactinomas and menopause: any changes in management?

PURPOSE

Treatment goals in prolactinomas are to correct hypogonadism, restore fertility and control tumor mass in case of macroadenomas. According to current guidelines, medical treatment of asymptomatic postmenopausal women is not indicated. The purpose of this study was to review the current literature pertaining to biological behavior of prolactinomas during menopause, likelihood of successful dopamine agonist withdrawal during this period and possible prolactin-mediated increased morbidity that could modify current management.

METHODS

A comprehensive literature search including papers published until July 2019 was conducted using PubMed and Medline databases.

RESULTS

Women with prolactinomas entering menopause have a higher chance of prolactin normalization of treatment compared with women in their reproductive years. Although most prolactin secreting adenomas diagnosed during menopause are large, they respond well to dopamine agonist treatment. Data directly linking hyperprolactinemia with an increased risk of cancer and cardiovascular and metabolic morbidity are inconsistent. There is no data indicating that correction of hyperprolactinemia improves clinical outcomes in asymptomatic patients bearing microadenomas.

CONCLUSION

There is no evidence that justifies changing current recommendations to withhold medical treatment of microprolactinomas in asymptomatic post-menopausal women. Macroprolactinoma patients should be treated according to standard clinical practice.

The incidence of anterior pituitary hormone deficiencies in patients with microprolactinoma and idiopathic hyperprolactinaemia

INTRODUCTION

Patients with microprolactinoma and idiopathic hyperprolactinaemia are not generally considered to be at risk of hypopituitarism and are therefore not routinely screened for this abnormality. In our clinical practice, we have observed a number of patients with nonmacroadenomatous hyperprolactinaemia to have anterior pituitary hormone deficits.

AIMS

We aimed to establish the frequency and clinical significance of anterior pituitary hormone deficiencies, comparing patients with radiologically proven microprolactinomas and patients with idiopathic hyperprolactinaemia.

STUDY DESIGN

We retrospectively examined the casenotes of 206 patients with hyperprolactinaemia from our centre. Patients who did not fit the profile of surgically naïve microprolactinoma or idiopathic hyperprolactinaemia or who had incomplete data were excluded, resulting in a study group of 56 patients.

RESULTS

A total of 35 patients with MRI evidence of microprolactinoma were identified, three (8.57%) of whom had one or more anterior pituitary hormone deficiencies. A total of 21 patients with MRI-negative idiopathic hyperprolactinaemia were identified, nine (42%) of whom had one or more anterior pituitary hormone deficiencies (P<.01). Only one patient in the MRI-positive group had deficiency that required hormone replacement, in contrast six patients in the MRI-negative group had deficiencies that were of clinical significance and which required hormone replacement.

SUMMARY

This study shows a clinically significant incidence of anterior pituitary hormone deficiency in patients with idiopathic hyperprolactinaemia. The authors recommend that dynamic pituitary assessment should be considered routinely in this patient group. A prospective study would be required to assess the underlying cause for these abnormalities, as they suggest a nontumour pan-pituitary process.

Prolactinomas in men: a multicentre and retrospective analysis of treatment outcome

AIMS

To assess treatment outcome in male patients with micro- and macroprolactinomas.

DESIGN

Multicentre and retrospective study.

PATIENTS

Eighty-eight male patients (15 micro- and 73 macroprolactinomas), aged 40·3 ± 14·7 years, were studied. Time of follow-up ranged from 3 to 244 months.

METHODS

Clinical, hormonal and radiological data were registered at diagnosis and follow-up. Treatment outcome was evaluated in relation to the modality of therapy (dopamine agonists, surgery and radiation therapy).

RESULTS

Dopamine agonists normalized prolactin levels in 73·3% and 65·2% of patients with micro- and macroprolactinomas, respectively. Disappearance of tumour was reached in 53·3% and 28·3% of subjects with micro- and macroprolactinomas, respectively. Tumour absence at last visit was achieved in 7 of 14 patients with macroprolactinoma and treated by means of dual therapy (dopamine agonists and neurosurgery) and in 9 of 13 patients with macroprolactinoma managed with triple therapy (dopamine agonists, neurosurgery and radiation therapy). Normalization of prolactin levels at last visit was present in 68·9%, 79·6% and 69·2% of patients treated by medical therapy, dual therapy and triple therapy, respectively (differences not significant). Multivariate logistic regression analysis showed that the time on therapy was the only significant variable related to tumour disappearance.

CONCLUSION

We conclude that medical therapy normalizes prolactin and reduces tumour size in the majority of men with prolactinomas. The addition of pituitary surgery with or without radiation therapy does not offer significant advantages over medical therapy with dopamine agonists in male patients with macroprolactinomas.

Hormonal evaluation of the infertile male: has it evolved?

An endocrinologic evaluation of patients who have male-factor infertility has clearly evolved and leads to specific diagnoses and treatment strategies in a large population of infertile men. A well-considered endocrine evaluation is especially essential with the ever-growing popularity of assisted reproductive techniques and continued refinements with intracytoplasmic sperm injection.

Advances in the treatment of prolactinomas

Prolactinomas account for approximately 40% of all pituitary adenomas and are an important cause of hypogonadism and infertility. The ultimate goal of therapy for prolactinomas is restoration or achievement of eugonadism through the normalization of hyperprolactinemia and control of tumor mass. Medical therapy with dopamine agonists is highly effective in the majority of cases and represents the mainstay of therapy. Recent data indicating successful withdrawal of these agents in a subset of patients challenge the previously held concept that medical therapy is a lifelong requirement. Complicated situations, such as those encountered in resistance to dopamine agonists, pregnancy, and giant or malignant prolactinomas, may require multimodal therapy involving surgery, radiotherapy, or both. Progress in elucidating the mechanisms underlying the pathogenesis of prolactinomas may enable future development of novel molecular therapies for treatment-resistant cases. This review provides a critical analysis of the efficacy and safety of the various modes of therapy available for the treatment of patients with prolactinomas with an emphasis on challenging situations, a discussion of the data regarding withdrawal of medical therapy, and a foreshadowing of novel approaches to therapy that may become available in the future.

Drug Insight: cabergoline and bromocriptine in the treatment of hyperprolactinemia in men and women

Prolactinoma is the most frequent pituitary tumor histotype. Men generally have macroadenomas whereas women generally have microadenomas. The major objectives of treating prolactinomas are to suppress excessive hormone secretion and its clinical consequences, to remove the tumor mass while preserving the residual pituitary function, and possibly to prevent disease recurrence or progression. Primary therapy of prolactinomas is based on use of dopamine-receptor agonists. Bromocriptine induces normalization of prolactin levels in 80-90% of patients with microprolactinomas and approximately 70% of those with macroprolactinomas. Tumor-mass shrinkage and improvement of visual-field defects are found in the majority of treated macroprolactinomas, but bromocriptine often causes side effects. Cabergoline is very effective and well tolerated in more than 90% of patients with either microprolactinomas or macroprolactinomas. Cabergoline treatment also induces tumor shrinkage in the majority of patients with macroprolactinomas. Tumor shrinkage is more evident if patients have not previously been treated with other dopamine agonists. Fewer results are available for men than for women, but there is no evidence that men are less responsive to dopamine agonists than are women.

[Prolactinomas and bone mineral density in men]

Throughout the years evidence has been accumulated on the morbidity of hyperprolactinemia, particularly in terms of bone mineral density decrease. This complication of hyperprolactinemia affects both women and men. In this paper, we analyze aspects related to bone loss in men with hyperprolactinemia due to prolactinomas: prevalence, clinical relevance, physiopathology, diagnosis and the consequences of the treatment of hyperprolactinemia and hypogonadism on bone mineral density.

Long-term efficacy of bromocriptine in macroprolactinomas and giant prolactinomas in men

We prospectively analyzed presentations and long-term therapeutic responses to bromocriptine (BRC) in 29 newly diagnosed men with macroprolactinomas including 14 patients with 'giant prolactinoma'. Clinical symptoms, prolactin (PRL) levels and tumor size on MRI were measured before BRC and sequentially thereafter. The duration of follow-up were 6 to 96 (30.7 +/- 14.4) months. Pretreatment PRL ranged between 124 and 29200 ng/mL (1698 +/- 857.1) and tumor volume was between 2.81 and 132 cm(3) (21.1 +/- 24.3). Baseline PRL levels did not correlated with tumor volume (r = 0.45, P > 0.05). Significant decrease (P = 0.0003) in PRL, at least 96% of the pretreatment value from 1698 +/- 857.1 ng/mL to 42.4 +/- 30.6 ng/mL occurred in 26 patients. Persistent normalization of PRL levels (< 16 ng/mL) for at least 6 months was achieved in 12 patients (40.8%). Twenty-two patients (74.8%) achieved significant tumor shrinkage (P = 0.005) at study completion. An improvement in visual field defects (VFD) and restoration of libido and potency was observed in 40% and 33.3%, respectively. Trans-sphenoidal / trans-frontal pituitary surgery was performed in 9 patients (31%) for various reasons: pituitary apoplexy in 1, CSF rhinorrhea in 2, increasing prolactin in spite of BRC therapy in 3, and intolerant /resistant to BRC in 3 patients. These data suggest that, in male macro- and giant prolactinomas, dopamine agonists represent the first-line therapy effective in reducing PRL, restoration of libido and potency, improvement of VFD and determining tumor shrinkage.

The relationship of changes in leptin, neuropeptide Y and reproductive hormones to antipsychotic induced weight gain

OBJECTIVES

Weight gain is an important side effect of antipsychotic (AP) treatment. Weight is regulated by multiple systems, including leptin, neuropeptide Y (NPY) and gonadal steroids. The aim was to investigate whether AP-induced weight gain was related to leptin and NPY abnormalities and whether these were associated with a disruption of gonadal steroid production.

METHODS

Twenty two female patients with schizophrenia receiving standard AP treatment were studied over a 3-month period. Plasma leptin, NPY, gonadal steroids and their regulators were measured along with weight and BMI.

RESULTS

Weight, leptin and testosterone levels increased over time. There were significant relationships between a change in oestrogen levels and both a change in NPY levels and a change in BMI. Change in BMI, weight and leptin all correlated strongly with a change in the testosterone/luteinizing hormone ratio.

CONCLUSIONS

AP treatment results in increase in weight over time and this increase is accompanied by increased leptin levels. AP-induced weight gain is also associated with disruption of the hypothalamic-pituitary-gonadal axis. Altered regulation of NPY, either through abnormal leptin control or serotonin blockade, is a possible explanation for the effects of AP medication on both weight and gonadal steroid levels.

The epidemiology, anatomy, physiology, and treatment of erectile dysfunction in chronic renal failure patients

Erectile dysfunction (ED) is an associated morbidity for men with chronic renal failure. An understanding of the epidemiology, anatomy, physiology, and treatment options for ED can greatly improve the quality of life for men with chronic renal failure. There are psychological and physiological causes for erectile dysfunction. Once the key features leading to the patient's loss of potency have been identified, appropriate treatment plans can be instituted, often with successful outcomes. The purpose of this article is to assist the nephrology interdisciplinary team in the management of ED by reviewing possible causes, available studies, and treatment options for their patients.

Is the measurement of serum testosterone routinely indicated in men with erectile dysfunction?

OBJECTIVE

To investigate the usefulness of serum testosterone levels as a relevant or useful indicator of sexual potency in men attending an erectile dysfunction clinic.

PATIENTS AND METHODS

Ninety consecutive men attending the erectile dysfunction clinic completed a sexual-activity questionnaire, and underwent a focused physical examination and questioning about their medical history. The serum testosterone level was measured in all patients and the results analysed in relation to the patient's age. Patients with low serum testosterone levels commenced replacement therapy comprising three intramuscular injections of testosterone (Sustanontrade mark, Organon, The Netherlands) 250 mg every third week. Potency status and serum testosterone were reassessed after 3 months' treatment.

RESULTS

Of the 90 men, 28 (31%) were aged < 50 years whilst 62 (69%) were >/=50 years old. Nineteen (21%) patients overall had low testosterone levels; four of these were < 50 and 15 were >/=50 years old. Five of 90 patients had a decreased libido; two of these also had low testosterone levels and all were < 50 years old. Testosterone levels returned to normal in all patients who received replacement therapy but potency returned in only two (10%); both were in the older group.

CONCLUSION

Measuring testosterone was not helpful in assessing potency or libido and low serum levels were not related to age. Correcting low testosterone did not improve either impotence or libido.

Hyperprolactinaemia among infertile patients and its effect on sperm functions

The effects of hyperprolactinaemia on sperm function were investigated in 264 men with oligozoo-, asthenozoo-, or teratozoospermia and who were attending a male infertility clinic. None of the patients exhibited galactorrhea or complained of impotence. There was no correlation between abnormal values in spermiogram and hyperprolactinaemia. After multiple measurements of serum prolactin concentration, 15 cases (5.7%) were diagnosed as hyperprolactinaemic (> or = 10 ng ml-1). Six of these patients were taking cimetidine and six were taking anti-anxiety drugs. Serum prolactin returned to the normal level after discontinuation of these drugs; thus these 12 cases were considered as drug-induced hyperprolactinaemia. The other three patients were diagnosed as having pituitary microadenomas and received bromocriptine treatment; the serum prolactin levels normalized within 1 month. No changes in sperm concentration, motility or morphology were found after normalization of serum prolactin levels. Sperm fertilizing ability was monitored by the hamster test for 10 months in the three patients with pituitary microadenoma, and no improvement was observed. Results suggest that hyperprolactinaemia, which does not cause symptoms, has little effect on the impairment of sperm functions. Measurement of serum prolactin in infertile men could be justified, however, for early detection of pituitary adenomas.

Prolactinoma in 53 men: clinical characteristics and modes of treatment (male prolactinoma)

The data of 53 men treated for hyperprolactinemia were reviewed retrospectively to determine the efficacy of the medical and surgical treatment. The clinical assessment, radiological and neuro-ophthalmological investigations and hormonal measurements were performed before treatment as well as during the follow-up period. Imaging evaluation included computed tomography and/or nuclear magnetic resonance of the pituitary. The hormonal profile examined was PRL, FSH, LH and testosterone, as well as TSH, T4, T3 and cortisol. Thirty patients were treated solely by dopamine agonists (DA), twenty-two men had pituitary surgery in addition to DA treatment, and one patient was operated with no need for medical treatment. Decreased sexual function was the most frequent presenting symptom (85% of the men). Most of the patients had large invasive macroadenomas, with suprasellar extension. More than 40% had visual field defects. Baseline PRL (mean +/- SE) was 51,842 +/- 9,292 mU/L and decreased to a level below 575 mU/L in 70% of the patients after DA therapy. Mean testosterone, FSH, and LH levels increased slightly but significantly from the low baseline values. Complete clinical response to DA was achieved in 49% of the men and the tumor mass disappeared entirely in 21%, and incompletely in 42%. The surgical success rate (transsphenoidal or trans-cranial operation) was low--only one of the 23 patients operated recovered completely, and most of the patients were left with hormonal deficits and hyperprolactinemia. These findings indicate that continuous medical treatment with DA should be the preferred mode of treatment for male prolactinomas. Removal of these large tumors is recommended only when the tumors are life-threatening or if drug resistance or severe adverse reactions to DA develop.

Correlations between presence of spontaneous lesions of the pituitary (adenohypophysis) and plasma prolactin concentration in aged Wistar rats

The predictive value of elevated plasma prolactin concentrations for the presence of spontaneous pituitary lesions was studied in 40 male and 38 female Wistar (Cpb:WU) rats, all 30 months old. The pituitaries were examined light microscopically and stained for prolactin using immunohistochemical methods. Plasma prolactin concentrations were measured by radioimmunoassay. Pituitary lesions were classified on the basis of their morphology in hematoxylin and eosin-stained sections as foci of hypertrophic or hyperplastic cells and hemorrhagic, pleomorphic, or spongiocytic adenomas; no carcinomas were found. There were significantly (P = 0.001) more female than male rats with pituitary adenomas (58% females, 33% males) or without any pituitary lesions (21% females, 5% males); however, there were less female (21%) than male rats (63%) with foci of hyperplastic and/or hypertrophic cells but no adenomas in the pituitary (P = 0.001). Elevation of plasma prolactin concentration above the upper 99th percentile value in age-matched rats without lesions was predictive, but not conclusively, of the presence of pituitary hemorrhagic adenomas in both sexes. It was, however, not predictive of the presence of foci of hypertrophic or hyperplastic cells. Elevation of plasma prolactin concentration above 10 ng/ml in male and 60 ng/ml in female rats was conclusive for the presence of hemorrhagic adenomas. Using multivariate analysis, significant positive correlations (P less than 0.01) were found between plasma prolactin concentration and presence and size of hemorrhagic adenomas and their prolactin staining intensity (correlation coefficients between 0.392 and 0.652). Foci of hyperplastic cells stained positively for prolactin, whereas hypertrophic cell foci and pleomorphic and spongiocytic adenomas did not stain for prolactin. There were no correlations (coefficients of less than +/- 0.189) between plasma prolactin concentration and the presence of hypertrophic or hyperplastic cell foci and pleomorphic or spongiocytic adenomas in the pituitary. The morphologic criteria developed to distinguish spontaneous hypertrophic, hyperplastic, and neoplastic lesions of the rat pituitary corresponded well with their prolactin immunoreactivity and/or ability to elevate plasma prolactin concentration. These criteria constitute a biologically meaningful classification system for these rat pituitary lesions.

Is routine endocrine testing of impotent men necessary?

Endocrine screening of impotent men is performed in an effort to identify a treatable cause of impotence. However, the prevalence of endocrinopathy in this patient population is low. We determined whether any historical or physical findings obtained during the initial office visit would identify a subgroup of patients at risk for endocrinopathy to decrease the cost of endocrine screening. The results of routine endocrine screening of 330 consecutive impotent patients formed the basis of this study. A total of 7 patients (2.1%) had endocrinopathy. Testicular atrophy was observed in 5 of these 7 patients and 6 reported decreased libido. All of the patients with endocrinopathy had either decreased libido or bilateral testicular atrophy. Our results indicate that the cost of impotence evaluation can be decreased by screening only those patients with clinical signs of hypogonadism, that is either decreased libido or bilateral testicular atrophy.

Hyperprolactinemia and impotence

One hundred impotent men and 15 sexually active male volunteers served as the source for this study. Serum prolactin was estimated in all cases using radioimmunoassay technique. Cases with hyperprolactinemia were treated with bromocriptine for 3 months. Hyperprolactinemia was detected in three patients only (3%), with no findings of pituitary tumors. Treatment with bromocriptine markedly reduced the level of serum prolactin together with improvement of sexual libido and potency. The mere presence of 3 cases only with hyperprolactinemia among 100 impotent subjects suggested that hyperprolactinemia is not one of the main causes of impotence.

Bromocriptine and the hypothalamic hypophyseal function in patients with chronic renal failure on chronic hemodialysis

Ten patients with chronic renal failure on chronic hemodialysis had the following tests to evaluate the integrity of the hypothalamic hypophyseal axis: (A) glucose tolerance test, (B) thyrotropin releasing hormone stimulation test, (C) clonidine stimulation test, (D) insulin induced hypoglycemia, and (E) LH/RH stimulation test. The majority of those tests were abnormal and prolactin values were found to be moderately elevated in all the patients. Bromocriptine (1.25 mg twice a day) was given to all the patients for 1 month and then, while on bromocriptine, the tests were repeated. Although there is a decrement in the concentration of serum prolactin level, none of the hypothalamic hypophyseal abnormalities were corrected. However, five of the ten patients reported an improvement of their impotence with bromocriptine. The patients who responded had high levels of FSH and LH with levels of testosterone above 1 mg/mL. The nonresponders had low FSH and LH levels and very low testosterone levels. Therefore, bromocriptine, although possibly beneficial in some dialysis patients, is not a drug that can normalize abnormal functioning of hormones in the dialysis population.

Intrasellar chordoma and hyperprolactinemia

An intrasellar chordoma in a patient with diplopia and hyperprolactinemia is presented. A brief review of the literature on intrasellar chordomas and the potential etiology for the hyperprolactinemia in this patient are discussed.

A decade of pituitary microsurgery. The Herbert Olivecrona lecture

The author reviews his experience with surgical treatment of 1000 pituitary tumors, the majority of which were endocrine-active. The criteria of grading, the microsurgical technique used, and the postoperative results are presented. The mortality rate was 0.2% overall, with no deaths in the group of 774 patients with endocrine-active adenomas.

Altered pulsatile secretion of luteinizing hormone in hypogonadal men with hyperprolactinaemia

To explore the mechanism for the hypogonadism associated with prolactin hypersecretion in men we examined luteinizing hormone (LH) secretory profiles in four hyperprolactinaemic men before and during treatment with bromocriptine. Pretreatment serum prolactin levels were increased 4-100 fold and serum testosterone levels were low in three men and low-normal in the fourth subject. Mean LH levels were low-normal and the frequency of spontaneous LH secretory episodes was less than normal in three of four men. Bromocriptine reduced serum prolactin levels to normal; subsequently, serum testosterone levels increased and libido and potency improved markedly in each man. The rise in serum testosterone levels was associated with an increase in mean LH concentrations and in LH pulse frequency. Mean follicle-stimulating hormone levels also increased during bromocriptine treatment. Insofar as each LH pulse is believed to reflect a discharge of gonadotrophin releasing hormone from the anterior hypothalamus, our data suggest that a major abnormality in hyperprolactinaemic men with hypogonadism is a disorder of the neuroregulatory mechanism for pulsatile gonadotrophin-releasing hormone secretion.

Hypogonadism, hyperprolactinaemia, and temporal lobe epilepsy in hyposexual men

Previously unrecognised temporal lobe epilepsy (TLE) was diagnosed in 11 of 16 hyposexual men. 6 had neuroendocrine abnormalities (hypogonadism in 4 and hyperprolactinaemia in 2). 4 men with hypogonadism and TLE had persistently subnormal serum testosterone, with a blunted luteinising hormone (LH) response to luteinising hormone releasing hormone (LHRH) in 2 and, in these men, unlike those with isolated hypogonadism, there was no improvement in libido or potency when parenteral testosterone was given. Men with TLE and hyperprolactinaemia had normal serum testosterone and an enhanced serum LH response after LHRH, but effective doses of the dopaminergic agonists, bromocriptine or pergolide, did not produce sustained normoprolactinaemia. In the men with neuroendocrine dysfunction and TLE the most effective therapeutic sequence was first to treat the epilepsy with anticonvulsants and then to add appropriate neuroendocrine therapy. In 2 men hormone levels became normal and sexual function was restored on anticonvulsant therapy alone.