Hyperprolactinaemia

Clinical and radiographic characteristics of patients with non-functioning pituitary adenomas categorized according to their serum prolactin concentration: novel predictors of postoperative transient diabetes insipidus following surgery

PURPOSE

Non-functioning pituitary adenomas (NFPAs) are often associated with hyperprolactinemia, which is known as the "stalk effect". However, the relationships between hyperprolactinemia and the radiographic characteristics of the tumor that affects the pituitary stalk have not been well characterized. We aimed to identify the differences in the clinical and radiographic characteristics of patients with NFPA, with and without hyperprolactinemia.

METHODS

We enrolled 107 patients with NFPA and allocated them to hyperprolactinemia and non-hyperprolactinemia groups using two different cut-off values: (1) the upper limit of the normal reference range, adjusted for sex and menopausal status, and (2) the upper quartile across the cohort, and compared their clinical and radiographic characteristics. These analyses were conducted to clarify the relationship between the "stalk effect" and the postoperative change in antidiuretic hormone secretion.

RESULTS

The specific radiographic characteristics of the patients included the presence of a cystic or hemorrhagic tumor and the presence of pituitary stalk deviation, which were more frequent in the patients with hyperprolactinemia. Interestingly, the incidence of postoperative transient diabetes insipidus was statistically significantly higher in the hyperprolactinemia group (≥40 ng/mL) and in the group with radiologic evidence of stalk deviation, which were shown to be independent risk factors on multivariate analysis.

CONCLUSION

The presence of a "stalk effect" was associated with a higher risk of postoperative transient diabetes insipidus, reflecting perioperative pituitary stalk dysfunction following NFPA surgery, especially in patients with serum prolactin concentrations ≥40 ng/mL and radiologic evidence of stalk deviation.

Bmal1 regulates female reproduction in mice via the hypothalamic-pituitary-ovarian axis

The hypothalamic-pituitary-gonadal axis (HPG) is the key neuroendocrine axis involved in reproductive regulation. Brain and muscle ARNT-like protein 1 (Bmal1) participates in regulating the metabolism of various endocrine hormones. However, the regulation of Bmal1 on HPG and female fertility is unclear. This study aims to explore the regulation of female reproduction by Bmal1 via the HPG axis in mice. Bmal1-knockout (Ko) mice were generated using the CRISPR/Cas9 technology. The structure, function, and estrous cycle of ovarian in Bmal1 Ko female mice were measured. The key genes and proteins of the HPG axis involved in regulating female reproduction were examined through transcriptome analysis and then verified by RT-PCR, immunohistochemistry, and western blot. Furthermore, the fertility of female mice was detected after intervening prolactin (PRL) and progesterone (Pg) in Bmal1 ko mice. The number of offspring and ovarian weight were significantly lower in Bmal1-Ko mice than in wild-type (Wt) mice. In Bmal1-Ko mice, ovarian cells were arranged loosely and irregularly, and the total number of follicles was significantly reduced. No corpus luteum was found in the ovaries. Vaginal smears revealed that Bmal1-Ko mice had an irregular estrus cycle. In Bmal1-Ko mice, Star expression was decreased, PRL and luteinizing hormone (LH) levels were increased, and dopamine (DA) and Pg levels were decreased. Inhibition of PRL partially recovered the estrous cycle, corpus luteum formation, and Star expression in the ovaries. Pg supplementation promoted embryo implantation in Bmal1-Ko female mice. Bmal1 Ko increases serum PRL levels in female mice likely by reducing DA levels, thus affecting luteal formation, resulting in decreased Star expression and Pg production, hindering female reproduction. Inhibition of PRL or restoration of Pg can partially restore reproductive capacity in female Bmal1-Ko mice. Thus, Bmal1 may regulate female reproduction via the HPG axis in mice, suggesting that Bmal1 is a potential target to treat female infertility.

A comprehensive review of the new FIGO classification of ovulatory disorders

BACKGROUND

The World Health Organization (WHO) system for the classification of disorders of ovulation was produced 50 years ago and, by international consensus, has been updated by the International Federation of Gynecology and Obstetrics (FIGO).

OBJECTIVE AND RATIONALE

This review outlines in detail each component of the FIGO HyPO-P (hypothalamic, pituitary, ovarian, PCOS) classification with a concise description of each cause, and thereby provides a systematic method for diagnosis and management.

SEARCH METHODS

We searched the published articles in the PubMed database in the English-language literature until October 2022, containing the keywords ovulatory disorders; ovulatory dysfunction; anovulation, and each subheading in the FIGO HyPO-P classification. We did not include abstracts or conference proceedings because the data are usually difficult to assess.

OUTCOMES

We present the most comprehensive review of all disorders of ovulation, published systematically according to the logical FIGO classification.

WIDER IMPLICATIONS

Improving the diagnosis of an individual's ovulatory dysfunction will significantly impact clinical practice by enabling healthcare practitioners to make a precise diagnosis and plan appropriate management.

Are prolactin levels efficient in predicting a pituitary lesion in patients with hyperprolactinemia?

PURPOSE

Data regarding the presence of a prolactin (PRL) threshold above which a pituitary magnetic resonance imaging (MRI) is mandatory in patients with hyperprolactinemia (hyperPRL) are controversial and derived primarily from studies focused on female populations. Aim of our study was to evaluate in a cohort of patients of both sexes with confirmed hyperPRL, the possible correlation between PRL values and the presence of pituitary abnormalities.

METHODS

We retrospectively analyzed data from patients who underwent serial PRL sampling at our Division between January 2015 and December 2022. Patients diagnosed with monomeric hyperPRL at serial sampling and with subsequent contrast-enhanced MRI results available for the pituitary region were included in the study. Exclusion criteria were prior pituitary disease, severe renal insufficiency, liver cirrhosis, uncompensated primary hypothyroidism and ongoing therapy with hyperprolactinemic drugs. Physiological causes of hyperPRL were also ruled out.

RESULTS

Out of the 1253 patients who underwent serial PRL sampling, 139 patients (101 women and 38 men) met the inclusion criteria: 106 (76.3%) patients had some form of pituitary disease, with microlesions observed in 69.8%, macrolesions in 25.5% and other findings in 4.7% of subjects. PRL values showed a modest accuracy in predicting the presence of a pituitary abnormality and the best cut-offs identified were >25 µg/L (AUC 0.767, p = 0.003) and >44.2 µg/L (AUC 0.697, p < 0.001) in men and women, respectively; however, if only patients with PRL values > 500 µg/L were excluded from the analysis, as they were already supposed to harbor a macroprolactinoma, PRL levels were not able to predict the presence of a macrolesion neither in men nor women.

CONCLUSION

Given the high prevalence of pituitary abnormalities in patients of both sexes with hyperPRL at serial sampling, performing a pituitary imaging in all cases of hyperPRL, even if mild, appears to be a cautious choice.

Determining Ideal Management for Patients With Coexisting Prolactinomas and Psychiatric Symptoms: A Systematic Review

OBJECTIVE

Prolactinomas-pituitary tumors that overproduce prolactin-can cause various troublesome symptoms. Dopamine agonists (DAs) reduce prolactin production in the prolactin pathway, making them the first-line treatment for prolactinomas. However, the main side effect of DA treatment, hyperdopaminergia, is an explicit etiology for psychiatric side effects. Psychiatric conditions are often treated with dopamine antagonists, which can induce hyperprolactinemia. This presents a challenge for patients with both a prolactinoma and a preexisting psychiatric condition, as treatment of one condition could worsen the other. This review seeks to identify an adequate therapeutic regimen for patients with coexisting prolactinomas and psychiatric symptoms.

METHODS

This review examined PubMed citations from 1960 to 2023 published in English and involving human subjects. Case reports, case series, and cohort studies involving patients with concomitant prolactinomas and psychiatric symptoms, as validated by brain imaging, serologic prolactin levels, and medical history or chart reports of psychiatric symptoms, were included.

RESULTS

Thematic analysis included 23 reports involving 42 participants; 27 of the 42 patients experienced a significant reduction in prolactin levels and psychiatric symptoms (64%). Treatment of those 42 patients included discontinuing or altering antipsychotic/dopamine antagonist therapy or discontinuing DA therapy to reduce psychiatric symptoms, with surgery or radiation postpharmacotherapy as a last-line strategy. However, in some cases (reported in Tables 2 to 4), either psychiatric or prolactin-related symptoms recurred despite adjustment.

CONCLUSIONS

Clinicians may find it beneficial to prioritize specific antipsychotics (aripiprazole, olanzapine, ziprasidone, or clozapine) over others (risperidone, thioridazine, thiothixene, and remoxipride). Discontinuing DA medication at least periodically until the patient's condition improves may also be advisable. If these 2 initial approaches do not yield a significant improvement in symptom management, surgery or radiation therapy may be considered. As patients may respond differently to these therapies, our study still recommends a patient-centered approach.

Diagnosis of hyperprolactinemia in women: A Position Statement from the Brazilian Federation of Gynecology and Obstetrics Associations (Febrasgo) and the Brazilian Society of Endocrinology and Metabolism (SBEM)

Hyperprolactinemia is a frequent cause of menstrual irregularity, galactorrhea, hypogonadism, and infertility. The most common etiologies of hyperprolactinemia can be classified as physiological, pharmacological, and pathological. Among pathological conditions, it is essential to distinguish prolactinomas from other tumors and pituitary lesions presenting with hyperprolactinemia due to pituitary stalk disconnection. Proper investigation considering clinical data, laboratory tests, and, if necessary, imaging evaluation, is important to identify the correctcause of hyperprolactinemia and manage the patient properly. This position statement by the Brazilian Federation of Gynecology and Obstetrics Associations (Febrasgo) and Brazilian Societyof Endocrinology and Metabolism (SBEM) addresses the recommendations for measurement of serum prolactin levels and the investigations of symptomatic and asymptomatic hyperprolactinemia and medication-induced hyperprolactinemia in women.

Treatment of sexual dysfunction induced by hyperprolactinemia accompanied by reduced luteinizing hormone levels: A case report

Key Clinical Message

Sexual dysfunction induced by hyperprolactinemia accompanied by reduced luteinizing hormone (LH) is common in anrology clinics. A low dose of bromocriptine is helpful for restoring penile erectile function and libido in patients.

Abstract

Sexual dysfunction is closely related to hormonal disorders, of which prolactin (PRL) and luteinizing hormone (LH) disorders are common. How to treat sexual dysfunction induced by hyperprolactinemia accompanied by reduced LH levels is worth discussing. In this study, we aimed to present the case of a 35-year-old male patient with sexual dysfunction. The treatment process and physical and laboratory examination results were recorded. Before treatment, the PRL and LH levels in this patient were 31.27 ng/mL and 1.62 mIU/mL, respectively. The International Index of Erectile Function-5 (IIEF-5) score was initially 14 points. After regular treatment with low doses of bromocriptine and tadalafil, the hormonal disorder was corrected (PRL: 11.16 ng/mL and LH: 2.28 mIU/mL) and sexual function was recovered (IIEF-5: 23 points). This case report suggested a sufficient exposure to low-dose bromocriptine for such patients. Conversely, the exogenous supplementation of human chorionic gonadotropin may not be appropriate.

Autoimmune Disorders Associated With Surgical Remission of Cushing's Disease : A Cohort Study

BACKGROUND

Glucocorticoids suppress inflammation. Autoimmune disease may occur after remission of Cushing's disease (CD). However, the development of autoimmune disease in this context is not well described.

OBJECTIVE

To determine 1) the incidence of autoimmune disease in patients with CD after surgical remission compared with patients with nonfunctioning pituitary adenomas (NFPAs) and 2) the clinical presentation of and risk factors for development of autoimmune disease in CD after remission.

DESIGN

Retrospective matched cohort analysis.

SETTING

Academic medical center/pituitary center.

PATIENTS

Patients with CD with surgical remission and surgically treated NFPA.

MEASUREMENTS

Cumulative incidence of new-onset autoimmune disease at 3 years after surgery. Assessment for hypercortisolemia included late-night salivary cortisol levels, 24-hour urine free cortisol (UFC) ratio (UFC value divided by the upper limit of the normal range for the assay), and dexamethasone suppression tests.

RESULTS

Cumulative incidence of new-onset autoimmune disease at 3 years after surgery was higher in patients with CD (10.4% [95% CI, 5.7% to 15.1%]) than in those with NFPAs (1.6% [CI, 0% to 4.6%]) (hazard ratio, 7.80 [CI, 2.88 to 21.10]). Patients with CD showed higher prevalence of postoperative adrenal insufficiency (93.8% vs. 16.5%) and lower postoperative nadir serum cortisol levels (63.8 vs. 282.3 nmol/L) than patients with NFPAs. Compared with patients with CD without autoimmune disease, those who developed autoimmune disease had a lower preoperative 24-hour UFC ratio (2.7 vs. 6.3) and a higher prevalence of family history of autoimmune disease (41.2% vs. 20.9%).

LIMITATION

The small sample of patients with autoimmune disease limited identification of independent risk factors.

CONCLUSION

Patients achieving surgical remission of CD have higher incidence of autoimmune disease than age- and sex-matched patients with NFPAs. Family history of autoimmune disease is a potential risk factor. Adrenal insufficiency may be a trigger.

PRIMARY FUNDING SOURCE

Recordati Rare Diseases Inc.

Current Insights in Prolactin Signaling and Ovulatory Function

Prolactin (PRL) is a pleiotropic hormone released from lactotrophic cells of the anterior pituitary gland that also originates from extrapituitary sources and plays an important role in regulating lactation in mammals, as well as other actions. Acting in an endocrine and paracrine/autocrine manner, PRL regulates the hypothalamic-pituitary-ovarian axis, thus influencing the maturation of ovarian follicles and ovulation. This review provides a detailed discussion of the current knowledge on the role of PRL in the context of ovulation and ovulatory disorders, particularly with regard to hyperprolactinemia, which is one of the most common causes of infertility in women. Much attention has been given to the PRL structure and the PRL receptor (PRLR), as well as the diverse functions of PRLR signaling under normal and pathological conditions. The hormonal regulation of the menstrual cycle in connection with folliculogenesis and ovulation, as well as the current classifications of ovulation disorders, are also described. Finally, the state of knowledge regarding the importance of TIDA (tuberoinfundibular dopamine), KNDγ (kisspeptin/neurokinin B/dynorphin), and GnRH (gonadotropin-releasing hormone) neurons in PRL- and kisspeptin (KP)-dependent regulation of the hypothalamic-pituitary-gonadal (HPG) axis in women is reviewed. Based on this review, a rationale for influencing PRL signaling pathways in therapeutic activities accompanying ovulation disorders is presented.

Prolactin-secreting pituitary adenomas: male-specific differences in pathogenesis, clinical presentation and treatment

Prolactinomas (PRLomas) constitute approximately half of all pituitary adenomas and approximately one-fifth of them are diagnosed in males. The clinical presentation of PRLomas results from direct prolactin (PRL) action, duration and severity of hyperprolactinemia, and tumor mass effect. Male PRLomas, compared to females, tend to be larger and more invasive, are associated with higher PRL concentration at diagnosis, present higher proliferative potential, are more frequently resistant to standard pharmacotherapy, and thus may require multimodal approach, including surgical resection, radiotherapy, and alternative medical agents. Therefore, the management of PRLomas in men is challenging in many cases. Additionally, hyperprolactinemia is associated with a significant negative impact on men's health, including sexual function and fertility potential, bone health, cardiovascular and metabolic complications, leading to decreased quality of life. In this review, we highlight the differences in pathogenesis, clinical presentation and treatment of PRLomas concerning the male sex.

Diagnosis and management of prolactin-secreting pituitary adenomas: a Pituitary Society international Consensus Statement

This Consensus Statement from an international, multidisciplinary workshop sponsored by the Pituitary Society offers evidence-based graded consensus recommendations and key summary points for clinical practice on the diagnosis and management of prolactinomas. Epidemiology and pathogenesis, clinical presentation of disordered pituitary hormone secretion, assessment of hyperprolactinaemia and biochemical evaluation, optimal use of imaging strategies and disease-related complications are addressed. In-depth discussions present the latest evidence on treatment of prolactinoma, including efficacy, adverse effects and options for withdrawal of dopamine agonist therapy, as well as indications for surgery, preoperative medical therapy and radiation therapy. Management of prolactinoma in special situations is discussed, including cystic lesions, mixed growth hormone-secreting and prolactin-secreting adenomas and giant and aggressive prolactinomas. Furthermore, considerations for pregnancy and fertility are outlined, as well as management of prolactinomas in children and adolescents, patients with an underlying psychiatric disorder, postmenopausal women, transgender individuals and patients with chronic kidney disease. The workshop concluded that, although treatment resistance is rare, there is a need for additional therapeutic options to address clinical challenges in treating these patients and a need to facilitate international registries to enable risk stratification and optimization of therapeutic strategies.

Influence of COVID-19 infection/vaccination on menstrual regularity and hormonal function in Saudi females of reproductive age

The COVID-19 pandemic has had a profound impact on women's health, particularly on their menstrual cycles. The menstrual cycle serves as a crucial indicator of fertility and reproduction.

Objectives

This study aimed to examine the impact of COVID-19 infection and vaccination on menstrual regularity in Saudi women of childbearing age. Additionally, it sought to explore the potential effects of COVID-19 vaccination on serum hormonal levels during the follicular phase of the menstrual cycle, along with their relationship with Vit.D.

Methods

This case‒control study investigated the impact of COVID-19 infection and vaccination on menstrual regularity and hormonal function in Saudi women of reproductive age. Data were collected from 79 women who attended the Outpatient Department of Obstetrics and Gynaecology at King Faisal Medical Complex in Taif, Saudi Arabia. All participants had received COVID-19 vaccines. The data collection process was comprehensive, encompassing various participant characteristics, such as demographic information, history of COVID-19 infection, and details about menstrual patterns before and after infection and vaccination. Furthermore, hormonal measurements, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), oestradiol, prolactin, thyroid-stimulating hormone (TSH), and vitamin D (Vit.D) levels, were extracted from the participants' medical records.

Results

Among the participants, 39.24 % had a history of COVID-19 infection, and following the infection, there was a significant increase in the proportion of women experiencing irregular menstruation. After receiving the COVID-19 vaccine, 72.15 % of the participants continued to have irregular menstrual cycles. The study found that a considerable number of participants had menstrual cycles outside the normal range, with 43.80 % having cycles shorter than 21 days and 35.10 % having cycles longer than 35 days. Comparing participants with regular and irregular cycles after COVID-19 vaccination, no significant changes were observed in most hormonal levels. However, the prolactin hormone showed a significant increase in participants with irregular cycles, while Vit.D levels were significantly decreased in this group.

Conclusion

The study findings indicate a higher prevalence of irregular menstruation among participants, particularly after vaccination. Notably, irregular menstrual cycles were found to be associated with elevated levels of prolactin hormone and decreased levels of Vit.D.

The importance of measuring prolactin prior to surgical management of a pituitary lesion: An illustrative case

The characterization of sellar and suprasellar lesions is reliant on patient presentation, medical imaging, and hormone profiling. Prolactinomas are the most common type of functional pituitary adenomas, accounting for up to 57%. Importantly, prolactinomas can present without clear symptoms and with doubtful or even normal imaging. A 41-year-old male patient was referred to neurosurgery for consideration for resection of a sellar lesion, as initial CT imaging suggested a large meningioma. Subsequent MRI of the sella favored macroadenoma, meningioma, and craniopharyngioma as the top differential considerations. These conditions all indicate a diagnosis that would require surgical management. Clinical evaluation of this patient did not elicit any obvious clinical features suggestive of hyperprolactinemia. Fortunately, we obtained a full hormone panel which revealed a significantly elevated prolactin level of 17,390 µg/L. Based on this elevated prolactin level, we diagnosed a pituitary giant prolactinoma. Treatment with a dopamine agonist therapy was initiated and the response confirmed this diagnosis. This case demonstrates the importance of obtaining a prolactin level prior to surgical management of a sellar lesion. Had a prolactin level not been obtained, this patient would have undergone surgical resection based on both the imaging and clinical judgment.

Current and Perspective Approaches to the Treatment of Prolactinomas

Background

Along with the presence of the 2011 Endocrine Society Clinical Practice Guidelines and numerous large-scale studies on the treatment of hyperprolactinemia of different origin, there are some unresolved questions, ambiguous and sometimes contradictory points of view regarding the management of patients with prolactinomas. This overview is devoted to the analysis of the results of modern clinical studies and the approaches towards the management of hyperprolactinemia caused by prolactinoma.

Materials and methods

A systematic research of the literature for the appropriate keywords published mainly for the last 10 years was done; also, a reference list of each selected article was analysed. We included to our review the articles reporting controversial issues or new data on the treatment of hyperprolactinemia.

Results

The review describes various problems arising during the treatment of prolactinoma. The presence of primary and secondary dopamine agonist resistance in each case requires an individual approach, and sometimes may include the use of the antineoplastic agent t emozolomide. The side effects of dopamine agonists are discussed, with quite rare ones, including valvulopathy, pathological psychological conditions and cerebrospinal rhinorrhea. The controversial issue of the duration and doses of the drug used to achieve a lasting effect in the treatment of prolactinomas is considered. There are some points connected with the frequency of relapses. Thus, recurrence is correlated to the duration of treatment with dopamine agonists, prolactin levels at diagnosis, and the initial tumor size. Metformin, somatostatin analogues, selective estrogen receptor modulators, tyrosine kinase inhibitors, inhibitors of the mammalian target of rapamycin, epidermal growth factor receptor antagonists are investigated nowadays as potential alternative methods of drug treatment of prolactinomas.

Conclusion

Drug therapy with dopamine agonists makes it possible to achieve the desired results in the vast majority of patients. However, despite the proven safety of this group of medicines, the risk of side effects should still be taken into account. The therapy regimen should be determined by the clinical course of prolactinoma and the patient's response to treatment. Other options of treatment should be considered in patients intolerant to medical therapy, with contraindication or resistance to dopamine agonists, in the case of a malignant tumor. The presence of refractory to any of the applied methods of treatment and aggressive prolactinomas leads to the search for new drugs.

The Effect of Metformin on Plasma Prolactin Levels in Young Women with Autoimmune Thyroiditis

Metformin decreases elevated prolactin levels, which are frequently found in patients with thyroid disorders. The aim of this study was to investigate whether thyroid autoimmunity modulates the impact of metformin on lactotrope secretory function. This study compared two matched groups of young women with prediabetes and mild-to-moderate prolactin excess: 28 subjects with coexisting euthyroid autoimmune thyroiditis (group 1) and 28 individuals without thyroid disorders (group 2), treated for six months with metformin (3 g daily). Thyroid antibody titers, glucose homeostasis markers, prolactin, thyrotropin, free thyroid hormones, FSH, LH, ACTH, IGF-1 and hsCRP were assessed at the beginning and at the end of the study. At entry, the study groups differed in antibody titers and hsCRP levels. Although the improvement in glucose homeostasis and the decrease in hsCRP levels were observed in both study groups, they were more pronounced in group 2. Only in group 2 did metformin reduce circulating prolactin levels (both total and monomeric). Prolactin-lowering properties of metformin positively correlated with baseline prolactin levels, baseline antibody titers (in group 1) and with the degree of reduction in hsCRP levels. The obtained results suggest that autoimmune thyroiditis may attenuate the impact of metformin on lactotrope secretory function.

Cardiometabolic Effects of Cabergoline and Combined Oral Contraceptive Pills in Young Women with Hyperprolactinemia: A Pilot Study

Although dopaminergic agents are the drugs of choice in treatment of prolactin excess, women who cannot be treated with these agents are recommended to receive estrogen preparations. The aim of this study was to compare cardiometabolic effects of both treatment options. The study population included three groups of young women. Subjects with mild-to-moderate hyperprolactinemia received either low-dose cabergoline or oral combined contraceptives (ethinyl estradiol plus desogestrel), while normoprolactinemic women were drug-naive. Plasma prolactin, glucose homeostasis markers, lipids, circulating levels of uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen and homocysteine, and the urinary albumin-to-creatinine ratio (UACR) were assessed at entry and six months later. Hyperprolactinemic women differed from normoprolactinemic ones in glucose homeostasis markers, high-density lipoprotein (HDL)-cholesterol, triglycerides, uric acid, hsCRP, fibrinogen, homocysteine and UACR. Cabergoline decreased total and monomeric prolactin levels, which was accompanied by normalization of glucose, insulin sensitivity, glycated hemoglobin, HDL-cholesterol, triglycerides, uric acid, hsCRP, fibrinogen, homocysteine and UACR. Despite a neutral effect on prolactin levels, combined contraceptives worsened insulin sensitivity and increased triglycerides, hsCRP, fibrinogen and UACR. At follow-up, cabergoline-treated women were characterized by a better cardiometabolic profile than women receiving ethinyl estradiol plus desogestrel. Our findings suggest that only cabergoline reduces cardiometabolic risk in young women with hyperprolactinemia.

Comparison of PEG precipitation and ultrafiltration treatment for serum macroprolactin in Chinese patients with hyperprolactinemia

BACKGROUND

Macroprolactinemia is a common cause of hyperprolactinemia (HPRL), with an average worldwide incidence of 18.9 %. This study aimed to explore the feasibility of ultrafiltration (UF) and polyethylene glycol (PEG) precipitation for macroprolactin screening, as well as the incidence and clinical characteristics of Chinese patients with macroprolactinemia.

METHODS

In this study, 94 patients with HPRL and 206 healthy individuals were included. Gel filtration chromatography (GFC), PEG precipitation, and UF were used to screen for macroprolactin, and chemiluminescence was used to determine the prolactin levels.

RESULTS

The detected incidence of macroprolactinemia in the patients with HPRL was 7.45% (7/94, GFC) and 5.32% (5/94, PEG precipitation). Patients with macroprolactinemia usually present with atypical clinical symptoms, moderately increased prolactin levels, and negative or microadenoma-positive pituitary images. In addition, the recovery of monomeric prolactin by PEG precipitation and UF was significantly correlated to that of GFC (r _PEG=0.493, P<0.001; r _UF=0.226, P=0.014), with a higher correlation coefficient between PEG precipitation and GFC. Furthermore, PEG precipitation had a smaller variation (95% confidence interval [CI]: -35.77% to 18.34%) than UF in monomeric prolactin recovery and substantial diagnostic consistency with GFC (Cohen's kappa coefficient=0.647). The proportion of monomeric prolactin in patients with HPRL did not change significantly between the two visits within one year (P >0.05).

CONCLUSION

The incidence of macroprolactinemia in Chinese patients with HPRL is low in the present study. Based on our analysis, we recommend that only patients who are clinically suspected of having macroprolactinemia should be screened using PEG precipitation.

Prolactin and morning cortisol concentrations in antipsychotic naïve first episode psychosis: A systematic review and meta-analysis

IMPORTANCE

Alterations in prolactin and cortisol levels have been reported in antipsychotic naïve patients with first episode psychosis (FEP). However, it has been studied in very small samples, and inter-group variability has never been studied before.

OBJECTIVE

To provide estimates of standardized mean differences (SMD) and inter-group variability for prolactin, cortisol awakening response (CAR) and morning cortisol concentrations in antipsychotic naïve FEP (AN-FEP) patients and healthy controls (HC).

DATA SOURCES

BIOSIS, KCI, MEDLINE, Russian Science Citation Index, SciELO, Cochrane, PsycINFO, Web of Science were searched from inception to February 28, 2022.

STUDY SELECTION

Peer-reviewed cohort studies that reported on prolactin or cortisol blood concentrations in AN- FEP patients and HC were included.

DATA EXTRACTION AND SYNTHESIS

Study characteristics, means and standard deviations (SD) were extracted from each article. Inter group differences in magnitude of effect were estimated using Hedges g. Inter-group variability was estimated with the coefficient of variation ratio (CVR). In both cases estimates were pooled using random-effects meta-analysis. Differences by study-level characteristics were estimated using meta-regression. PRISMA guideline was followed (No. CRD42022303555).

MAIN OUTCOMES AND MEASURES

Prolactin, CAR and morning cortisol blood concentrations in AN-FEP group in relation to HC group.

RESULTS

Fourteen studies for prolactin (N = 761 for AN-FEP group, N = 687 for HC group) and twelve studies for morning cortisol (N = 434 for AN-FEP group, N = 528 for HC group) were included. No studies were found in CAR in AN-FEP patients. Mean SMD for prolactin blood concentration was 0.88 (95% CI 0.57, 1.20) for male and 0.56 (95% CI 0.26, 0.87) for female. As a group, AN-FEP presented greater inter-group variability for prolactin levels than HC (CVR=1.28, 95% CI 1.02, 1.62). SMD for morning cortisol concentrations was non-significant: 0.34 (95% CI -0.01, 0.69) and no inter-group variability significant differences were detected: CVR= 1.05 (95% CI 0.91, 1.20). Meta-regression analyses for age and quality were non-significant. Funnel plots did not suggest a publication bias.

CONCLUSIONS AND RELEVANCE

Increased prolactin levels were found in AN-FEP patients. A greater inter-group variability in the AN-FEP group suggests the existence of patient subgroups with different prolactin levels. No significant abnormalities were found in morning cortisol levels. Further research is needed to clarify whether prolactin concentrations could be used as an illness biomarker.

Efficacy and safety profiles of mood stabilizers and antipsychotics for bipolar depression: a systematic review

The whole picture of psychotropics for bipolar depression (BPD) remains unclear. This review compares the differences in efficacy and safety profiles among common psychotropics for BPD. MEDLINE, EMBASE, and PsycINFO were searched for proper studies. The changes in the depressive rating scale, remission/response rates, nervous system adverse events (NSAEs), gastrointestinal adverse events (GIAEs), metabolic parameters, and prolactin were compared between medication and placebo or among medications with the Cohen's d or number needed to treat/harm. The search provided 10 psychotropics for comparison. Atypical antipsychotics (AAPs) were superior to lithium and lamotrigine at alleviating acute depressive symptoms. Lithium was more likely to induce dry mouth and nausea. Cariprazine and aripiprazole seemed to be associated with an increased risk of akathisia and upper GIAEs. Lurasidone was associated with an increased risk of developing akathisia and hyperprolactinemia. Olanzapine, olanzapine-fluoxetine combination (OFC), and quetiapine were associated with an increased risk of NSAEs, metabolic risk, dry mouth, and constipation. Cariprazine, lurasidone, OFC, or quetiapine was optimal monotherapy for BPD. Further studies are needed to assess the efficacy and safety of lamotrigine for treating BPD. Adverse events varied widely across different drug types due to variations in psychopharmacological mechanisms, dosages, titration, and ethnicities.

Effects of Tele-Pilates and Tele-Yoga on Biochemicals, Physical, and Psychological Parameters of Females with Multiple Sclerosis

BACKGROUND

People with multiple sclerosis (PwMS) suffer from some comorbidities, including physical and psychiatric disorders, low quality of life (QoL), hormonal dysregulation, and hypothalamic-pituitary-adrenal axis dysfunction. The current study aimed to investigate the effects of eight weeks of tele-yoga and tele-Pilates on the serum levels of prolactin and cortisol and selected physical and psychological factors.

METHODS

Forty-five females with relapsing remitting multiple sclerosis, based on age (18-65), expanded disability status scale (0-5.5), and body mass index (20-32), were randomly assigned to tele-Pilates, tele-yoga, or control groups (n = 15). Serum blood samples and validated questionnaires were collected before and after interventions.

RESULTS

Following online interventions, there was a significant increase in the serum levels of prolactin (p = 0.004) and a significant decrease in cortisol (p = 0.04) in the time × group interaction factors. In addition, significant improvements were observed in depression (p = 0.001), physical activity levels (p < 0.001), QoL (p ≤ 0.001), and the speed of walking (p < 0.001).

CONCLUSION

Our findings suggest that tele-yoga and tele-Pilates training could be introduced as patient-friendly, non-pharmacological, add-on therapeutic methods for increasing prolactin and decreasing cortisol serum levels and achieving clinically relevant improvements in depression, walking speed, physical activity level, and QoL in female MS patients.

The Role of Aromatase Inhibitors in Male Prolactinoma

BACKGROUND

dopamine agonists are the recommended treatment for male prolactinomas, but some patients may develop dopamine-agonist-resistant hyperprolactinemia, leading to persistent hypogonadism that requires treatment with testosterone. However, testosterone replacement therapy may be associated with a decrease in the efficacy of dopamine agonists due to the aromatization of testosterone to estradiol, which can stimulate the proliferation and hyperplasia of lactotroph cells in the pituitary, inducing resistance to dopamine agonists.

OBJECTIVE

this paper systematically reviewed the role of aromatase inhibitors for men with prolactinoma and dopamine-agonist-resistant or persistent hypogonadism following treatment.

METHOD

we performed a systematic review of all studies (according to PRISMA guidelines), assessing the role of aromatase inhibitors, including anastrozole and letrozole, for male prolactinoma. An English-language search for relevant studies was conducted on PubMed from its inception to 1 December 2022. The reference lists of the relevant studies were also reviewed.

RESULTS

our systematic review identified six articles (nine patients), including five case reports and a single case series, on the use of aromatase inhibitors for male prolactinomas. Reducing estrogen levels with an aromatase inhibitor improved sensitivity to dopamine agonists, as the addition of anastrozole or letrozole improves the control of prolactin levels and may lead to the shrinkage of tumors.

CONCLUSION

aromatase inhibitors are of potential value to patients with dopamine-agonist-resistant prolactinoma, or when hypogonadism persists while using high-dose dopamine agonists.

Italian Guidelines for the Management of Prolactinomas

INTRODUCTION

This guideline (GL) is aimed at providing a reference for the management of prolactin (PRL)-secreting pituitary adenoma in adults. However, pregnancy is not considered.

METHODS

This GL has been developed following the methods described in the Manual of the Italian National Guideline System. For each question, the panel appointed by Associazione Medici Endocrinologi (AME) has identified potentially relevant outcomes, which have then been rated for their impact on therapeutic choices. Only outcomes classified as "critical" and "important" have been considered in the systematic review of evidence and only those classified as "critical" have been considered in the formulation of recommendations.

RESULTS

The present GL provides recommendations regarding the role of pharmacological and neurosurgical treatment in the management of prolactinomas. We recommend cabergoline (Cab) vs. bromocriptine (Br) as the firstchoice pharmacological treatment to be employed at the minimal effective dose capable of achieving the regression of the clinical picture. We suggest that medication and surgery are offered as suitable alternative first-line treatments to patients with non-invasive PRL-secreting adenoma, regardless of size. We suggest Br as an alternative drug in patients who are intolerant to Cab and are not candidates for surgery. We recommend pituitary tumor resection in patients 1) without any significant neuro-ophthalmologic improvement within two weeks from the start of Cab, 2) who are resistant or do not tolerate Cab or other dopamine-agonist drugs (DA), 3) who escape from previous efficacy of DA, and 4) who are unwilling to undergo a chronic DA treatment. We recommend that patients with progressive disease notwithstanding previous tumor resection and ongoing DA should be managed by a multidisciplinary team with specific expertise in pituitary diseases using a multimodal approach that includes repeated surgery, radiotherapy, DA, and possibly, the use of temozolomide.

CONCLUSION

The present GL is directed to endocrinologists, neurosurgeons, and gynecologists working in hospitals, in territorial services or private practice, and to general practitioners and patients.

Integrated Proteotranscriptomics of the Hypothalamus Reveals Altered Regulation Associated with the FecB Mutation in the BMPR1B Gene That Affects Prolificacy in Small Tail Han Sheep

The litter size and ovulation rate are different among ewes of different FecB genotypes in Small Tail Han sheep. These variants in reproductive phenotypes may be regulated by hormones released by the hypothalamic-pituitary-ovarian axis. However, there have been few reports on the hypothalamus regarding regulating an increase in ovulation in sheep with FecB mutation at different estrous stages. Thus, we examined the abundance of hypothalamus tissue protein profiles of six FecB mutant homozygous (BB) and six wild-type (WW) ewes at the luteal and follicular phases. We determined this abundance by tandem mass tag-based quantitative analysis and parallel reaction monitoring methods. Furthermore, an integrated proteotranscriptomic analysis was performed by the Data Integration Analysis for Biomarker discovery using the latent variable approaches for Omics studies (DIABLO) framework to examine biological processes and pathway alterations by the FecB mutant. The abundance of 154 proteins was different between the two estrous stages. Growth hormone and prolactin were particularly enriched in the neuroactive ligand-receptor interactions, the prolactin signaling pathway, and the PI3K-Akt signaling pathway which are related to hypothalamic function and reproduction. We combined proteome and transcriptome data from different estrous stages and genotypes. There is a high correlation (Pearson correlation coefficient = 0.99) between the two datasets in the first two components. We applied the traditional single-omic multivariate approach to obtain differentially abundant proteins and differentially expressed genes. The major fertility related biomarkers were selected using the two approaches mentioned above. Several key pathways (GABAergic synapse, neuroactive ligand-receptor interaction, estrogen and MAPK signaling pathways) were enriched, which are central to gonadotrophin-releasing hormone (GnRH) secretion and reproduction. A higher level of gamma-aminobutyric acid type A receptor subunit alpha1 (GABRA1) and gamma-aminobutyric acid type A receptor subunit beta2 (GABRB2) expression was observed in BB ewes as compared to WW ewes. This finding suggested that a greater production of GnRH during follicular development in BB ewes may explain the higher mature follicle number in mutant ewes. FKBP prolyl isomerase 1A (FKBP1A), which was a major feature factor in the proteome selected by DIABLO, was an important switch for activating the transforming growth factor beta (TGFβ) pathway, and its expression was higher in the WW ewes than in the BB ewes. We suggest that BB sheep maintain TGFβ pathway activity by reducing FKBP1A protein abundance. This innovative data integration in the hypothalamus may provide fresh insight into the mechanisms by which the FecB mutation affects sheep fertility, while providing novel biomarkers related to reproductive endocrinology in sheep breeding.

Cabergoline Failure and a Spontaneous Pregnancy in a Microprolactinoma with High Prolactin Levels

We report a particular case of a spontaneously occurring pregnancy in a long-term amenorrheic patient due to a prolactinoma with high serum prolactin (PRL) following the failure of dopamine agonist therapy (DA) for infertility. Initially, clinical, laboratory, and genital ultrasounds were normal, but the serum PRL was 10,074 μIU/mL (n.v.: 127−637 μIU/mL), the PEG fraction was 71% (laboratory cut-off > 60%), and luteinizing hormone (LH) was significantly lower. An MRI revealed a pituitary tumor of 12.8/10 mm with a subacute intratumoral hemorrhage. DA was initiated, and menstrual bleeding reappeared with a reduction in the tumor’s volume to 1.9/2.2 mm at 12 months. Two years later, the patient renounced DA and follow-ups. After another 2 years, she became spontaneously pregnant. Serum PRL was 18,325 μIU/mL, and an MRI revealed a microprolactinoma of 2.1/2 mm. The patient gave birth to a normal baby at term, and she breastfed for six months, after which she asked for ablactation, and DA was administered. This case highlights the possibility of the occurrence of a normal pregnancy during a long period of amenorrhea induced by a microprolactinoma with a high level of serum PRL, even if DA fails to correct infertility. There was no compulsory relationship between the tumoral volume’s evolution and the evolution of its lactophore activity. The hypogonadotrophic hypogonadism induced by high PRL was mainly manifested by low LH, and in this situation, normal levels of FSH and estradiol do not always induce follicle recruitment and development without abnormalities in the ovary ultrasound.

Prolactin immunoassay: does the high-dose hook effect still exist?

PURPOSE

Measurement of prolactin in clinical laboratories is an important component in the management of patients with pituitary adenoma. Prolactin measurement is known to be sensitive to the high-dose hook effect, in the presence of extremely high prolactin concentrations. This interference is referred to in most recent articles discussing prolactin assays and the management of prolactin-secreting pituitary adenomas. The objective of our study was to evaluate if the high-dose hook effect remains relevant in current practice, when using currently available assays.

METHODS

Serum from a patient with a giant macroprolactinoma was assayed using all of the available prolactin assays in France in 2020, using native serum and after dilution. Technical inserts from assays were reviewed to assess the information on analytical principles, numbers of steps, and any reference to high dose hook effect.

RESULTS

Fourteen assay kits were studied by 16 laboratories; all were two-site immunometric assays, mostly using one step (11/14). Results obtained after dilution varied from 17,900 µg/L to 86,900 µg/L depending on the assay used. One tested assay was sensitive to the high-dose hook effect leading to a falsely lower prolactin concentration when measuring native serum (150 µg/L compared to 17,900 µg/L after dilution).

CONCLUSION

The high-dose hook effect still exists in a very small minority of prolactin assays. The evolution of assay methods may lead to new assays that remain sensitive to this effect in the future. We therefore advise that the hook effect should still be mentioned in prolactin assay recommendations.

Bone microarchitecture impairment in prolactinoma patients assessed by HR-pQCT

PURPOSE

Prolactinoma may reduce bone mineral density (BMD) and increase fracture risk, but its influence on bone microarchitecture remains to be elucidated. The purpose of this study is to evaluate bone microarchitecture parameters by high-resolution peripheral quantitative computed tomography (HR-pQCT) in prolactinoma patients.

METHODS

31 prolactinoma patients and 62 age- and sex-matched healthy controls in our center were included, and HR-pQCT was used to evaluate their bone microarchitecture at the radius and tibia. Z-scores for bone microarchitecture parameters were calculated based on previously published reference.

RESULTS

After adjusting for height and weight, prolactinoma patients had lower trabecular (- 0.011 mm, p = 0.005) and cortical thickness (- 0.116 mm, p = 0.008) and cortical area (- 6.0 mm2, p = 0.013) at radius, as well as lower trabecular (- 0.014 mm, p = 0.008) and cortical (- 0.122 mm, p = 0.022) thickness at tibia compared with the controls. Patients with higher prolactin level had more severe bone microarchitecture impairments. After adjusting for prolactin level and age, male patients had lower trabecular volumetric BMD (vBMD), trabecular number, trabecular thickness, and cortical porosity at radius, as well as lower trabecular vBMD, trabecular bone volume fraction, trabecular number, and cortical area, and higher trabecular separation at tibia compared with female patients. Z-score for radius vBMD was correlated with Z-score for areal BMD (aBMD) at lumbar and femoral neck, while Z-score for tibia vBMD was correlated with Z-score for lumbar aBMD, and some patients with vBMD Z-score below - 2.0 had aBMD Z-score within normal range.

CONCLUSION

Peripheral bone microarchitecture was impaired in prolactinoma patients, especially in patients with higher prolactin level. We compared the bone microarchitecture of prolactinoma patients and healthy controls by high-resolution peripheral quantitative computed tomography (HR-pQCT), and found that many bone microarchitecture parameters were impaired among prolactinoma patients. Such impairment was more prominent among patients with higher prolactin level.

Italian Association of Clinical Endocrinologists (AME) and International Chapter of Clinical Endocrinology (ICCE). Position statement for clinical practice: prolactin-secreting tumors

Prolactinomas are the most frequent pituitary adenomas. Prolactinoma may occur in different clinical settings and always require an individually tailored approach. This is the reason why a panel of Italian neuroendocrine experts was charged with the task to provide indications for the diagnostic and therapeutic approaches that can be easily applied in different contexts. The document provides 15 recommendations for diagnosis and 54 recommendations for treatment, issued according to the GRADE system. The level of agreement among panel members was formally evaluated by RAND-UCLA methodology. In the last century, prolactinomas represented the paradigm of pituitary tumors for which the development of highly effective drugs obtained the best results, allowing to avoid neurosurgery in most cases. The impressive improvement of neurosurgical endoscopic techniques allows a far better definition of the tumoral tissue during surgery and the remission of endocrine symptoms in many patients with pituitary tumors. Consequently, this refinement of neurosurgery is changing the therapeutic strategy in prolactinomas, allowing the definitive cure of some patients with permanent discontinuation of medical therapy.

Clinical utility of serum prolactin and lactate concentrations to differentiate epileptic seizures from non-epileptic attacks in the emergency room

PURPOSE

To evaluate the diagnostic utility of serum prolactin (PRL) and lactate (LAC) concentrations for patients presenting with either or both convulsions and transient loss of consciousness (TLOC) in the emergency room (ER).

METHODS

This was a retrospective single-center study conducted in a tertiary care hospital ER. Medical records of consecutive patients who presented with convulsions or TLOC between January 2018 and December 2020 were reviewed. Patients with an ER diagnosis of epileptic seizures, psychogenic non-epileptic seizure (PNES), and syncope were selected for analysis. Serum PRL and LAC concentrations were measured within 3 h of the event and compared between groups.

RESULTS

Among the 440 eligible patients, 173 (39.3%) were included for analysis. Serum PRL concentration was significantly higher in patients with epileptic seizures with convulsions than in those with PNES with convulsions (p < 0.001) and convulsive syncope (p = 0.023). Serum LAC concentration was not significantly elevated in patients with convulsive syncope. Using a PRL cut-off value of 24.0 ng/mL, serum PRL concentration had 100.0% sensitivity and 82.9% specificity for differentiating between PNES and other attacks without convulsions.

CONCLUSION

Elevated serum PRL with normal serum LAC concentration in patients who have attacks with convulsions suggests convulsive syncope. Serum PRL concentration is useful in the diagnosis of PNES with convulsions. However, serum LAC concentration is not useful as a routine screening test for attacks without convulsions in the ER.

Relationship between styrene exposure and prolactin secretion in human and animal studies: A systematic review

Styrene is widely used in industrial applications. Inhalation exposure occurs in the industry. Some studies indicated that serum prolactin concentrations increased after exposure to styrene, while other studies found no change. In this systematic review, the search was done with the keywords styrene and prolactin in the PubMed, Science Direct, Web of Science and Scopus databases, regardless of the publication period. 118 studies were obtained and only seven articles were finally selected according to exclusion and inclusion criteria. The effect of styrene on prolactin secretion was selected in both human and animal studies. The increased response was seen in inhalation exposures. Subcutaneous exposure has no significant effect on prolactin levels. The observed responses were both dose-dependent and gender-dependent. Changes in serum prolactin were more frequent in women compared to exposed men. Dopamine depletion was not observed in all studies, so more tests on laboratory animals are necessary to clarify the possible mechanism.

Prolactin Reduces Hippocampal Parvalbumin and GABAA Receptor Expression in Female Mice

INTRODUCTION

Parvalbumin (PV)-positive cells are strategic elements of neuronal networks capable of influencing memory and learning processes. However, it is not known whether pituitary hormones may be related to PV expression in the hippocampus - a part of the limbic system with important functions in learning and memory.

OBJECTIVE

Since previous studies indicate that prolactin (PRL) plays a significant role in hippocampal-dependent learning and synaptic plasticity, we hypothesized that a rise in PRL levels can modify PV expression in the hippocampus.

METHODS

We employed biochemical, immunohistochemistry, and densitometry techniques - as well as a behavioural assay - in a hyperprolactinemia model using subcutaneous osmotic pumps in female mice.

RESULTS

PRL treatment via osmotic pump induced an increase in PRL receptor (PRLR) expression in most regions of the hippocampus analysed by Western blotting and immunohistochemistry methods. Fluorescent densitometry analysis revealed that PV expression decreases in the same layers in the hippocampus following PRL treatment, while double labelling immunostaining indicated close localization of PV and PRLR in PV-positive interneurons. In addition, we found that PRL induced a reduction in the β2/3 subunit of GABAA receptor (GABAAR) expression that was linearly correlated with the reduction in PV expression. This reduction in the β2/3 subunit of GABAAR expression was maintained in trained animals in which PRL treatment improved the learning of a spatial memory task.

CONCLUSIONS

These data show, for the first time, that an increase in PRL level is associated with changes in key constituent elements of inhibitory circuits in the hippocampus and may be of relevance for the alterations in cognitive function reported in hyperprolactinemia.

Metabolic effects of prolactin and the role of dopamine agonists: A review

Prolactin is a polypeptide hormone that is well known for its role in reproductive physiology. Recent studies highlight its role in neurohormonal appetite regulation and metabolism. Elevated prolactin levels are widely associated with worsening metabolic disease, but it appears that low prolactin levels could also be metabolically unfavorable. This review discusses the pathophysiology of prolactin related metabolic changes, and the less commonly recognized effects of prolactin on adipose tissue, pancreas, liver, and small bowel. Furthermore, the effect of dopamine agonists on the metabolic profiles of patients with hyperprolactinemia are discussed as well.

Aggressive prolactinoma (Review)

Aggressive prolactinoma (APRL) is a subgroup of aggressive pituitary tumors (accounting for 10% of all hypophyseal neoplasia) which are defined by: invasion based on radiological and/or histological features, a higher proliferation profile when compared to typical adenomas and rapidly developing resistance to standard medication/protocols in addition to an increased risk of early recurrence. This is a narrative review focusing on APRL in terms of both presentation and management. Upon admission, the suggestive features may include increased serum prolactin with a large tumor diameter (mainly >4 cm), male sex, early age at diagnosis (<20 years), and genetic predisposition [multiple endocrine neoplasia type 1 (MEN1), aryl hydrocarbon receptor interacting protein (AIP), succinate dehydrogenase (SDHx) gene mutations]. Potential prognostic factors are indicated by assessment of E-cadherin, matrix metalloproteinase (MMP)-9, and vascular endothelial growth factor (VEGF) status. Furthermore, during management, APRL may be associated with dopamine agonist (DA) resistance (described in 10-20% of all prolactinomas), post-hypophysectomy relapse, mitotic count >2, Ki-67 proliferation index ≥3%, the need for radiotherapy, lack of response in terms of controlling prolactin levels and tumor growth despite multimodal therapy. However, none of these as an isolated element serves as a surrogate of APRL diagnosis. A fourth-line therapy is necessary with temozolomide, an oral alkylating chemotherapeutic agent, that may induce tumor reduction and serum prolactin reduction in 75% of cases but only 8% have a normalization of prolactin levels. Controversies surrounding the duration of therapy still exist; also regarding the fifth-line therapy, post-temozolomide intervention. Recent data suggest alternatives such as somatostatin analogues (pasireotide), checkpoint inhibitors (ipilimumab, nivolumab), tyrosine kinase inhibitors (TKIs) (lapatinib), and mTOR inhibitors (everolimus). APRL represents a complex condition that is still challenging, and multimodal therapy is essential.

Levels of prolactin and testosterone and associated sexual dysfunction and breast abnormalities in men with schizophrenia treated with antipsychotic medications

Sexual dysfunction is one of the most bothersome adverse drug effects seen in men and women taking antipsychotic medications and negatively impacts medication adherence. Antipsychotic medications are associated with hyperprolactinemia, which is known to contribute to sexual and hormonal side effects in men. However, testosterone also plays a key factor in male sexual function and may be affected by abnormal prolactin levels through gonadotropin-releasing hormone inhibition. This study was a pilot study undertaken to assess the prevalence of elevations in prolactin levels, related reductions in testosterone levels, associated symptoms of sexual dysfunction and breast abnormalities in male participants, and related distress to these symptoms in men taking prolactin-elevating antipsychotic medications. The study was conducted as a cross-sectional study. Our results showed a notably high prevalence of sexual side effects in this population, with gynecomastia occurring in 50% and penile-related symptoms in 73%. Additionally, we found elevated prolactin levels in 68% and low testosterone levels in 55% of our participants. This study was limited in its power due to a small sample size of 22 men and the lack of a control group. Still, even in our relatively small sample, we see a trend of hyperprolactinemia being associated with low testosterone and a significant correlation of low testosterone levels with penile-related symptoms. This suggests that testosterone plays a major role in the sexual side effects reported by men taking antipsychotics, although larger studies are needed to further categorize this relationship.

Prolactinomas

Hyperprolactinemia, defined by a level of serum prolactin above the standard upper limit of normal range, is a common finding in clinical practice and prolactinomas are the main pathological cause. Prolactinomas lead to signs and symptoms of hormone oversecretion, such as galactorrhea and hypogonadism, as well as symptoms of mass effect, including visual impairment, headaches and intracranial hypertension. Diagnosis involves prolactin measurement and sellar imaging, but several pitfalls are involved in this evaluation, which may difficult the proper management. Treatment is medical in the majority of cases, consisting of dopamine agonists, which present high response rates, with a very favorable safety profile. Major adverse effects that should be monitored consist of cardiac valvulopathy and impulse control disorders. Other treatment options include surgery and radiotherapy. Temozolomide may be used for aggressive or malignant carcinomas. Finally, pregnancy outcomes are similar to general population even when dopamine agonist treatment is maintained.

Tumor volume improves preoperative differentiation of prolactinomas and nonfunctioning pituitary adenomas

PURPOSE

Both prolactinomas and nonfunctioning adenomas (NFAs) can present with hyperprolactinemia. Distinguishing them is critical because prolactinomas are effectively managed with dopamine agonists, whereas compressive NFAs are treated surgically. Current guidelines rely only on serum prolactin (PRL) levels, which are neither sensitive nor specific enough. Recent studies suggest that accounting for tumor volume may improve diagnosis. The objective of this study is to investigate the diagnostic utility of PRL, tumor volume, and imaging features in differentiating prolactinoma and NFA.

METHODS

Adult patients with pathologically confirmed prolactinoma (n = 21) or NFA with hyperprolactinemia (n = 58) between 2013 and 2020 were retrospectively identified. Diagnostic performance of clinical and imaging variables was analyzed using receiver-operating characteristic curves to calculate area under the curve (AUC).

RESULTS

Tumor volume and PRL positively correlated for prolactinoma (r = 0.4839, p = 0.0263) but not for NFA (r = 0.0421, p = 0.7536). PRL distinguished prolactinomas from NFAs with an AUC of 0.8892 (p < 0.0001) and optimal cut-off value of 62.45 ng/ml, yielding a sensitivity of 85.71% and specificity of 94.83%. The ratio of PRL to tumor volume had an AUC of 0.9647 (p < 0.0001) and optimal cut-off value of 21.62 (ng/ml)/cm³ with sensitivity of 100% and specificity of 82.76%. Binary logistic regression found that PRL was a significant positive predictor of prolactinoma diagnosis, whereas tumor volume, presence of cavernous sinus invasion, and T2 hyperintensity were significant negative predictors. The regression model had an AUC of 0.9915 (p < 0.0001).

CONCLUSIONS

Consideration of tumor volume improves differentiation between prolactinomas and NFAs, which in turn leads to effective management.

Efficacy and safety in the treatment of hyperprolactinemia: A systematic review and network meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Hyperprolactinemia is a neuroendocrine disease that is responsible for a quarter of cases of secondary amenorrhea, which can lead to infertility in women. Dopaminergic agonists (bromocriptine, cabergoline, quinagolide) can be used in the treatment. However, there is a lack of secondary studies that compare their efficacy and safety, especially through a network meta-analysis. Thus, to contribute to the decision-making, a systematic review and network meta-analyses (NMA) were performed to evaluate the efficacy and safety of dopaminergic agonists in the treatment of hyperprolactinemia.

METHODS

Randomized clinical trials (RCT) were retrieved through PubMed, Web of Science and Scopus databases. The efficacy and safety of the drugs were compared, considering the following outcomes: prolactin (PRL) levels, number of patients with galactorrhoea, menstrual irregularities and adverse drug reactions. NMA was built for each outcome. Results were reported as odds ratios (OR) with 95% credibility intervals. Ranking probabilities were calculated by surface under the cumulative ranking analysis (SUCRA) and Stochastic multicriteria acceptability analysis (SMAA).

RESULTS AND DISCUSSION

Seventeen RCTs were included in the systematic review and fifteen in the meta-analyses. The drugs had similar efficacy, considering the PRL levels. The SUCRA analysis showed that quinagolide (0.075 and 0.05 mg/day) was superior for reducing irregular menstruation, whereas bromocriptine was the best (97%) for galactorrhoea. Cabergoline proved to be the safest drug, except for abdominal pain at a dose of 1 mg/week. The SMAA demonstrated similar results to SUCRA.

WHAT IS NEW AND CONCLUSION

This is the first network meta-analysis that evaluated the efficacy and safety of dopaminergic agonists in the treatment of hyperprolactinemia. The results of this review revealed that these drugs have similar efficacy, but cabergoline has a better safety profile.

Hypeprolactinemia: still an insidious diagnosis

Hyperprolactinemia can have different causes: physiological, pharmacological, and pathological. When investigating the etiology of hyperprolactinemia, clinicians need to be aware of several conditions leading to misdiagnosis. The most popular pitfalls are: acute physical and psychological stress, macroprolactin, hook effect, even though antibodies interferences and biotine use have to be considered. A 52-year-old woman was referred to Endocrinology clinic for oligomenorrhoea and headache. She worked as a butcher. Hormonal evaluation showed very high PRL (305 ng/ml, reference interval: <24 ng/ml) measured with the ECLIA immunoassay analyzer Elecsys 170. The patient's pituitary MRI was normal and macroprolactin was normal. Hormonal workup showed LH: 71.5 mU/ml (2-10.9 mU/ml), FSH: 111.4 mU/ml (3.9-8.8 mU/ml), Estradiol: 110.7 pg/mL (27-122 pg/ml). Since an interference was suspected, the sample was sent to another laboratory using a different assay. After antibody blocking tubes treatment (Heterophilic Blocking Tube, Scantibodies) PRL was 28.8 ng/ml (reference interval < 29.2 ng/ml). Analytical interference should be suspected when assay results are not consistent with the clinical picture. Endogenous antibodies (EA) include heterophile, human anti-animal, autoimmune and other nonspecific antibodies, and rheumatoid factors, that have structural similarities and can cross-react with the antibodies employed by the immunoassay, causing hyperprolactinemia misdiagnosis. The patient's job (butcher), led us to suspect the presence of anti-animal antibodies. Clinicians should also carefully investigate the use of supplements. Biotin can falsely increase hormone concentration in competitive assays. Many clinicians are still not informed about these pitfalls that are not mentioned in some recent reviews on PRL measurement.

Prolactin as a neuroendocrine clue in sexual function of women across the reproductive life cycle: an expert point of view

Prolactin is a proteic hormone best known for its role in enabling the production of milk by female mammals. Secreted by the pituitary gland in response to the stimuli of eating, estrogen treatment, mating, ovulation and nursing, prolactin is involved in over 300 separate processes in a range of vertebrates, including humans. The hormone is released in a pulsatile manner and plays an essential role in metabolism, as well as in the regulation of the immune system and pancreatic development. Nevertheless, prolactin exerts other relevant roles, as it acts at the central nervous system level to modulate behavior, arousal and sexuality. In this experts' opinion, we aim to give insights into the main activities of prolactin to advance the ability of medical doctors and specialists in obstetrics and gynecology to provide more emphasis in their clinical practices to the link between prolactin and sexuality.

Identification of an optimal prolactin threshold to determine prolactinoma size using receiver operating characteristic analysis

Prolactinomas represent the most common type of secretory pituitary neoplasms, with a therapeutic management that varies considerably based on tumour size and degree of hyperprolactinemia. The aim of the current study was to evaluate the relationship between serum prolactin (PRL) concentrations and prolactinoma size, and to determine a cut-off PRL value that could differentiate micro- from macro-prolactinomas. A retrospective cohort study of 114 patients diagnosed with prolactinomas between 2007 and 2017 was conducted. All patients underwent gadolinium enhanced pituitary MRI and receiver operating characteristic (ROC) analyses were performed. 51.8% of patients in this study were men, with a mean age at the time of diagnosis of 42.32 ± 15.04 years. 48.2% of the total cohort were found to have microadenomas. Baseline serum PRL concentrations were strongly correlated to tumour dimension (r = 0.750, p = 0.001). When performing the ROC curve analysis, the area under the curve was 0.976, indicating an excellent accuracy of the diagnostic method. For a value of 204 μg/L (4338 mU/L), sensitivity and specificity were calculated at 0.932 and 0.891, respectively. When a cut off value of 204 μg/L (4338 mU/L) was used, specificity was 93.2%, and sensitivity 89.1%, acceptable to reliably differentiate between micro- and macro- adenomas.

Pituitary Dysfunction as a Cause of Cardiovascular Disease

The hypothalamic-pituitary axis is responsible for the neuroendocrine control of several organ systems. The anterior pituitary directly affects the functions of the thyroid gland, the adrenal glands, and gonads, and regulates growth and milk production. The posterior hypophysis, through nerve connections with the hypothalamic nuclei, releases vasopressin and oxytocin responsible for water balance and social bonding, sexual reproduction and childbirth, respectively. Pituitary gland hormonal excess or deficiency results in dysregulation of metabolic pathways and mechanisms that are important for the homeostasis of the organism and are associated with increased morbidity and mortality. Cardiovascular (CV) disorders are common in pituitary disease and have a significant impact on survival. Hormonal imbalance is associated with CV complications either through direct effects on the heart structure and function and vasculature or indirectly by altering the metabolic profile. Optimal endocrine control can prevent or reverse CV defects and preserve survival and quality of life. In this review, we discuss the effects of pituitary hormone excess and deficiency on the CV system. Specifically, we assess the impact of Somatotroph, Corticotroph, Gonadotroph, and Lactotroph anterior pituitary axes on the CV system. The effect of posterior pituitary function on the CV system is also explored.

Optimization of a Screening Method for Macroprolactinemia

OBJECTIVE

To optimize a screening method for macroprolactinemia and improve the accuracy of free prolactin (freePRL) detection.

METHOD

Overall efficiency, calculated as the product of the immunoglobulin G (IgG) precipitation rate and the freePRL recovery rate were employed to determine the concentration of the precipitant polyethylene glycol (PEG). Then, an optimized screening method for macroprolactinemia was established. The concentrations of freePRL, obtained by gel filtration chromatography (GFC), from 66 cases were used as the gold standard, and the sensitivity, specificity, accuracy and precision of the optimized and traditional methods for detecting macroprolactinemia were compared.

RESULTS

(1) The IgG precipitation rate increased with increasing PEG6000 concentration, and the freePRL recovery rate decreased with increasing PEG6000 concentration; the overall efficiency first increased and then decreased. When the IgG concentrations in the mixture were 10 g/L, 25 g/L and 40 g/L, the concentrations of PEG6000 with the highest overall efficiency were 24%, 20% and 18%, respectively. (2) The effect of high and low IgG on the overall efficiency was 4.7% when using 20% PEG6000, which was lower than the effects when using 18% or 24% PEG6000 (9.2% and 13.2%). (3) In the optimized method established using 20% PEG6000, the macroprolactin (macroPRL) chromatographic peak disappeared, but the freePRL chromatographic peak was retained. The sensitivity of this macroprolactinemia screening method was 96.7%, and the specificity was 100%. (4) The freePRL concentrations obtained by the optimized method for samples from 30 macroprolactinemia cases and 36 true hyperprolactinemia cases were 15.8 (10.2-21.4) ng/mL and 60.2 (51.8-79.9) ng/mL; the concentrations were similar to those obtained using the GFC method (16.3 (11.9-27.2) ng/mL and 68.1 (49.5-92.9) ng/mL, respectively (p > 0.05)) and higher than those obtained using the traditional method (9.1 (6.1-17.6) ng/mL and 51.4 (43.7-71.9) ng/mL), respectively, p < 0.05)). (5) The relative deviation between the optimized and GFC methods was -7.0%, which was significantly lower than the relative deviation between the traditional and GFC methods (-21.4%, p < 0.01). (6) The in-batch coefficients of variation (CVs) for the dual-level quality control materials measured by the optimized method were 1.88% and 1.87%, and the within-laboratory CVs were 2.55% and 2.29%, which were slightly lower than the in-batch CVs (1.93% and 2.81%) and within-laboratory CVs (2.75% and 2.81%) measured by the traditional method.

CONCLUSION

The established optimized method for screening macroprolactinemia using 20% PEG6000 as a precipitant can completely precipitate macroPRL components and effectively retain freePRL components. Compared with traditional methods, the optimized method is simpler, more accurate and more stable for the quantitative detection of freePRL.

The utility of prolactin serial sampling and the best prolactin cut-offs associated with persistent hyperprolactinemia

Background:

A single prolactin sampling is recommended for the diagnosis of hyperprolactinemia. We aimed to study the utility of the prolactin serial sampling and to determine the best cut-offs associated with persistent hyperprolactinemia.

Methods:

Retrospective study of hyperprolactinemic patients [referral prolactin (rPRL)] that underwent prolactin serial samplings. Prolactin at 0 minutes (PRL0′), 20 to 30, and 40 to 60 minutes. The lowest of these last 2 was defined as nadir prolactin (nPRL). Persistent hyperprolactinemia was defined as nPRL above normal. We excluded patients under dopamine receptor agonists. Receiver-operating characteristic (ROC) curves were used to determine the best rPRL and PRL0′ cut-offs predicting persistent hyperprolactinemia.

Results:

We studied 53 patients (3 males). Median rPRL 48.0 ng/mL (39.5–72.5), PRL0′ 34.3 ng/mL (18.0–50.8) and nPRL 29.5 ng/mL (11.4–44.4). PRL0′ was elevated in 35 (66.0%) patients and in 7 of them a normal nPRL was reached; therefore 28 (52.8%) had persistent hyperprolactinemia. The area under curve (AUC) for the association between rPRL and persistent hyperprolactinemia was 0.70 (95%CI: 0.56–0.84); best cut-off: 53.4 ng/mL [sensitivity 53.6%, specificity 80.0%, positive predictive value (PPV) 75.0%, and negative predictive value (NPV) 60.6%]. In the 35 patients with elevated PRL0′, the AUC was 0.92 (95%CI: 0.81–1.00); best cut-off: 35.2 ng/mL (sensitivity 85.7%, specificity 85.7%, PPV 60.0%, and NPV 96.0%).

Conclusions:

Approximately 1/3 of the patients reached a normal PRL0′. In an additional 20%, prolactin normalized after serial samplings. Patients with rPRL >53.4 ng/mL had 75% probability of having persistent hyperprolactinemia and those with PRL0′ <35.2 ng/mL had a 96% probability of not having persistent hyperprolactinemia.

Increase in serum prolactin levels in females improves the performance of spatial learning by promoting changes in the circuital dynamics of the hippocampus

Beyond the direct physiological functions associated with motherhood in mammals, previous studies have suggested the potential role of prolactin (Prl) in distinct brain processes such as neuroprotection, neurogenesis, and stress responses. However, the cognitive influence of Prl remains unclear, particularly regarding the mechanisms of acquisition, consolidation and retrieval of information in the brain. Using chronic implanted electrodes in freely moving female mice combined with behavioral tests, we investigated the rhythmic activity changes induced by Prl in a model of hippocampus-dependent learning and memory. Our results show that Prl improves the learning of a spatial memory task in the acquisition stage. The main variations at the circuitry level were in the theta frequency band (4-8 Hz and 8-12 Hz), marked by a faster change in oscillatory activity with no modifications to higher frequencies. These results show that Prl plays a significant role in the acquisition of information during learning of a spatial memory task, suggesting that an increase in Prl levels may induce changes in circuital network plasticity.

Healthcare utilization and costs among prolactinoma patients: a cross-sectional study and analysis of determinants

PURPOSE

Prolactinomas are the most prevalent functioning pituitary adenomas. They affect gonadal function as well as health-related quality of life (HRQoL). This study aimed to report healthcare utilization and costs, including their determinants, for prolactinoma patients.

METHODS

Cross-sectional study of 116 adult prolactinoma patients in chronic care in a Dutch tertiary referral center. Patients completed four validated questionnaires, assessing healthcare utilization and costs over the previous 12 months (Medical Consumption Questionnaire), disease bother and needs (Leiden Bother and Needs Questionnaire Pituitary), HRQoL (Short Form-36), and self-reported health status (EuroQol 5D). Regression analyses were used to assess associations between disease-related characteristics and healthcare utilization and costs.

RESULTS

Mean age was 52.0 years (SD 13.7) and median follow-up was 15.0 years (IQR 7.6-26.1). Patients visited the endocrinologist (86.2%), general practitioner (37.9%), and ophthalmologist (25.0%) most frequently. Psychological care was used by 12.9% of patients and 5% were admitted to hospital. Mean annual healthcare costs were €1928 (SD 3319), mainly for pituitary-specific medication (37.6% of total costs), hospitalization (19.4%) and specialist care (16.1%). Determinants for higher healthcare utilization and costs were greater disease bother and needs for support, lower HRQoL, elevated prolactin, and longer disease duration, while tumor size, hypopituitarism and adrenal insufficiency were not significantly associated with healthcare utilization and costs.

CONCLUSION

Healthcare utilization and costs of prolactinoma patients are related to patient-reported HRQoL, bother by disease and needs for support. Therefore, addressing patients' HRQoL and needs is a way forward to improve efficiency of care and patients' health status.

Antipsychotics-induced hyperprolactinemia and screening for macroprolactin

Introduction

High prolactin (PRL) concentrations are found in laboratory test results of patients on majority of antipsychotic drugs. Prevalence rates and degrees of severity of hyperprolactinemia (HPRL) based on PRL concentration may depend on the presence of macroprolactin in the serum. The aim of the study was to investigate the difference between PRL concentrations before and after precipitation of macroprolactin and to examine if there were any changes in the categorization of HPRL between samples prior and after precipitation.

Materials and methods

Total of 98 female patients (median age 33; range 19-47 years) diagnosed with a psychotic disorder, proscribed antipsychotic drugs, and with HPRL were included. Total PRL concentration and PRL concentration after macroprolactin precipitation with polyethylene glycol (postPEG-PRL) were determined by the chemiluminometric method on the Beckman Coulter Access2 analyser.

Results

Total PRL concentrations (median 1471; IQC: 1064-2016 mlU/L) and postPEG-PRL concentrations (median 1453; IQC: 979-1955 mlU/L) were significantly correlated using intraclass correlation coefficient for single measurements (mean estimation 0.96; 95%CI 0.93-0.97) and average measurement (mean estimation 0.98; 95%CI 0.96-0.99), and all investigated female patient had HPRL according to PRL and postPEG-PRL concentration. The median PRL recovery following PEG precipitation was 95; IQC: 90-100%. There was substantial agreement (kappa test = 0.859, 95% CI: 0.764-0.953) between the categories of HPRL severity based on total PRL concentrations and postPEG-PRL concentrations.

Conclusion

The study demonstrated that HPRL was present in all subjects using the reference interval for total PRL concentration and postPEG-PRL concentration with no significant impact of macroprolactin presence in the serum on the categorization of patients according to severity of HPRL.