Exploring the association of serum prolactin with serum glucose levels and clinical findings in a cohort of patients with early rheumatoid arthritis.

BACKGROUND: In the context of rheumatoid arthritis and its systemic inflammatory implications, there is an increasing interest in investigating the role of prolactin in the clinical and metabolic aspects of the disease. This study aimed to explore the potential links between serum prolactin levels, serum glucose levels, and the clinical manifestations of arthritis. METHODS: This exploratory, cross-sectional, observational study focused on women diagnosed with rheumatoid arthritis. The research involved assessing prolactin and blood glucose concentrations, alongside specific clinical traits such as disease-related inflammation, morning stiffness, and fatigue intensity. The presence of changes in serum prolactin (PRL) was initially compared among the groups based on disease activity intensity. Using a multinomial regression analysis, the study analyzed the impact of predetermined clinical and metabolic factors on various categories of prolactin concentration. RESULTS: Out of the 72 participants included in the study, hyperprolactinemia was detected in 9.1% of the sample. No differences in serum PRL were identified among the evaluated groups based on disease activity. Following multivariate analysis, no statistically significant differences were identified for the outcomes of inflammatory activity and morning stiffness within each PRL category when compared to the reference category for PRL. There was no increased likelihood of encountering blood glucose levels below 100 mg/dl among individuals with higher prolactin concentrations compared to those in the lowest prolactin category (OR 5.43, 95% CI 0.51-58.28). The presence of clinically significant fatigue revealed a higher likelihood of encountering this outcome among patients with intermediate PRL values (prolactin categories 7.76-10.35 with OR 5.18, 95% CI 1.01-26.38 and 10.36-15.29 with OR 6.25, 95% CI 1.2-32.51) when compared to the reference category. CONCLUSIONS: The study found no discernible correlation between prolactin concentrations and worse scores for inflammatory activity of the disease, nor between prolactin concentrations and serum glucose levels. The findings regarding fatigue should be approached with caution given the exploratory nature of this study.

No unfavorable effects on the menstruation recovery of early postoperative hypoprolactinemia after transsphenoidal surgery in patients with lactotroph pituitary neuroendocrine tumor.

OBJECTIVE: Transsphenoidal surgery for lactotroph pituitary neuroendocrine tumor (PitNET) lowers serum prolactin concentrations, occasionally below the normal range. However, the clinical significance of postoperative hypoprolactinemia is still unclear. In this study, we retrospectively reviewed the female patients with lactotroph PitNET who were treated with transsphenoidal surgery to elucidate the influence of postoperative hypoprolactinemia on regular menstruation restoration and endocrinological remission. RESULTS: The serum prolactin levels in all thirty three participating females had decreased following surgery. Serum prolactin levels in seven patients had decreased below the lower limit of normal ranges (hypoproactinemia group) and in the remaining twenty six patients, it was within the normal range (non-hypoproractinemia group). In hypoprolactinemia group, regular menstruation was restored in all patients with only lactotroph axis deficiency. Nine patients from the non-hypoprolactinemia group experienced re-elevation of serum prolactin concentration (27%). No patient in hypoprolactinemia group experienced the relapse of hyperprolactinemia. These data suggest that early postoperative hypoprolactinemia after transsphenoidal surgery for lactotroph PitNET is not only a good predictive factor for endocrinological remission but also no unfavorable effects on regular menstruation restoration.

Long-term proton pump inhibitors therapy and prevalence of hyperprolactinaemia: A cross-sectional study in outpatient gastroenterology clinics.

Objectives: To evaluate serum prolactin and macroprolactin levels in patients on long-term proton pump inhibitors therapy. METHODS: The cross-sectional study was conducted from January 2018 to November 2019 after approval from the ethics review committee of the Commission on Science and Technology for Sustainable Development in the South University, Abbottabad, Pakistan. The study included patients from two gastroenterology outpatient clinics in the Khyber Pakhtunkhwa province using proton pump inhibitors for ≥3 months either alone or in combination with either histamine receptor antagonists or prokinetics. Blood samples were collected from each patient for hormonal screening. Data was analysed using SPSS 25. RESULTS: Of the 166 patients, 101(60.8%) were females and 65(39.2%) were males. The overall mean age was 42.5±14.2 years, and the median serum prolactin level was 23.2ng/ml (interquartile range: 14.0-38.0ng/ml). There were 96(58%) patients with normoprolactinaemia and 70(42%) with hypreprolactinaemia. There were 19(11.4%) patients using combination therapy, while the rest were on proton pump inhibitors monotherapy. There was a significant increase in serum prolactin level with combination therapy compared to monotherapy (p=0.001). Patients having treatment duration 11-20 months (p=0.006) and >40 months (p=0.001) were at high risk of developing hyperprolactinaemia. CONCLUSIONS: Long-term use of proton pump inhibitors could increase serum prolactin levels, and appropriate evaluation is essential for clinical management.

Comparative efficacy of metformin combined with cabergoline versus metformin alone in patients with PCOS and hyperprolactinemia: A systematic review and meta-analysis of randomized controlled trials.

Isntroduction. Polycystic ovary syndrome (PCOS) is a multifaceted endocrine-gynecological condition affecting a substantial number of women during their reproductive years. Metformin (MET) has been shown to improve ovarian function in PCOS-related conditions, while cabergoline is recognized for its powerful and sustained ability to reduce prolactin levels. This study investigates the potential impact of combining cabergoline with metformin while comparing it with metformin alone in the treatment of PCOS alongside hyperprolactinemia. METHOD: To gather data, we searched PubMed, Google Scholar, ScienceDirect, and Cochrane Central. Eligible studies were randomized controlled trials involving patients with PCOS and hyperprolactinemia. Outcome measures included changes in the levels of prolactin, testosterone, DHEAS, BMI and menstrual irregularities. RevMan version 5.4 was used to analyze outcomes. RESULT: This study incorporated three Randomized Controlled Trials (RCTs) involving 405 participants in total. Patients receiving a combination of metformin and cabergoline experienced significant reductions in prolactin and testosterone levels (p= <0.0001 and p=<0.0001, respectively). Conversely, alterations in DHEAS levels and BMI did not reach statistical significance (p = 0.19 and p = 0.71, respectively). Notably, women solely prescribed metformin exhibited significantly higher rates of menstrual irregularities compared to those receiving both metformin and cabergoline (p=<0.0001). CONCLUSION: Our analysis underscores the synergistic effect achieved by pairing metformin and cabergoline in patients with PCOS and hyperprolactinemia. However, we encountered only a restricted number of studies meeting our criteria. It is imperative to consistently assess the combined effects of metformin and cabergoline to gain deeper insights into their effectiveness in addressing PCOS and hyperprolactinemia.

Sex-specific differences in the clinical profile among psychiatric patients with pulmonary Embolism: a hospital-based retrospective study.

BACKGROUND: Pulmonary embolism (PE) is a severe and life-threatening complication of venous thromboembolism. However, there is a lack of systematic studies on differences between female and male PE patients. This paper aimed to compare the sex-specific differences in clinical characteristics and laboratory indicators in psychotic patients with PE. METHODS: This retrospective study enrolled psychiatric patients with PE from June 2018 to June 2022 at Shenzhen Kangning Hospital (Shenzhen Mental Health Center). Demographic characteristics, factors associated with PE, and laboratory indices were collected to assess sex-specific differences. RESULTS: Of the 168 patients, 87 (51.8%) were female and 81 (48.2%) were male, with a mean age of 58 years for females and 46 years for male patients. The male group had higher ratio of hyperprolactinemia, more patients using antipsychotic medications, higher D-dimer levels at PE onset, greater D-dimer difference, and a higher rate of D-dimer elevation than the female group (p < 0.05). Female patients were significantly older, exhibited a higher prevalence of diabetes, and had a greater number of patients taking antidepressants and hypnotics/sedatives than male patients (p < 0.05). Schizophrenia spectrum disorders were more prevalent in male patients, while female patients had a higher incidence of mood disorders (p < 0.05). Among patients aged < 45 years, the male group had higher D-dimer levels at PE onset and greater D-dimer difference (p < 0.05). Among all 112 patients aged ≥ 45 years, male patients were more likely than female patients to have respiratory tract infections, higher D-dimer levels at PE onset, greater D-dimer difference, and a higher rate of D-dimer elevation (p < 0.05). The multiple linear regression analysis indicated that hyperprolactinemia and the use of first-generation antipsychotics (FGAs) were associated with D-dimer levels at PE onset in male patients, while the time of PE onset and protective restraints were associated with D-dimer levels at PE onset in female patients (p < 0.05). CONCLUSION: PE-associated clinical features differ between male and female patients. These differences may imply that the processes and mechanisms of PE onset are sex specific. Male patients are more likely to have respiratory tract infections and higher D-dimer levels at PE onset than female patients. The use of FGAs may be associated with increased D-dimer in male psychiatric patients, while protective restraints may be associated with increased D-dimer in female psychiatric patients.

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.

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.

[Acromegaly screening in patients with hyperprolactinemia and pituitary adenoma].

BACKGROUND: Hyperprolactinemia accompanies growth hormone hypersecretion in approximately 25-39% of cases. There is a recommendation to determine the level of prolactin in clinical guidelines for diagnosis and treatment of acromegaly. However, there is no understanding of the necessity to investigate the IGF-1 level in patients with hyperprolactinemia and a pituitary adenoma. AIM: Determining the proportion of patients with hyperprolactinemia and pituitary adenoma, who were examined for IGF-1 levels, and identifying the proportion of patients with acromegaly among this cohort. MATERIALS AND METHODS: Between December 2019 and December 2022 a single-center observational single-stage single-sample uncontrolled study was conducted. At the first stage of the study, the proportion of patients with pituitary adenoma and hyperprolactinemia with studied IGF-1 levels was determined, according to medical records. At the second stage of the study, patients without known indicators of IGF-1 were determined. The concentration of growth hormone was studied during the oral glucose load in the case of increased IGF-1 levels. RESULTS: At the first stage, 105 patients were included in the study. The level of IGF-1 was determined in 41/105 (39%) cases. There were 22/41 (53.7%) cases in the subgroup with pituitary incidentalomas and 19/64 (29.7%) cases in the subgroup with hyperprolactinemia among them. At the second stage, the IGF-1 level was additionally determined in 53 patients with hyperprolactinemia and pituitary adenoma (total 94 patients). The level of IGF-1 was elevated in 11/94 patients, further acromegaly was confirmed in 3/94 patients (3.2%). CONCLUSION: In real clinical practice the level of IGF-1 is studied only in 39% of cases in patients with pituitary adenoma and hyperprolactinemia. The disease was detected in 3 cases (3.2%) out of 94 people with hyperprolactinemia and pituitary adenoma without clinical manifestations of acromegaly. We consider the study of IGF-1 levels justified as a screening for acromegaly in patients with hyperprolactinemia and pituitary adenoma.

Prevalence of Hyperprolactinemia and Clinically Apparent Prolactinomas in Men Undergoing Fertility Evaluation.

OBJECTIVE: To determine prevalence of hyperprolactinemia and prolactinoma among men presenting for initial fertility evaluation. METHODS: We performed a retrospective review of men presenting for initial fertility evaluation at a tertiary care, academic health system between 1999 and 2018. Men with measured prolactin levels were analyzed to determine prevalence of hyperprolactinemia and prolactinoma. We compared clinical characteristics of men with and without hyperprolactinemia. Univariable and multivariable analysis were used to determine factors associated with hyperprolactinemia. We assessed effects of hyperprolactinemia and prolactinoma on testosterone levels, semen parameters and pregnancy outcomes after treatment. RESULTS: A total of 3101 men had serum prolactin level measured. 65 (2.1%) had hyperprolactinemia. Patients with hyperprolactinemia had lower testosterone (median 280 ng/dL vs 313 ng/dL, P = 0.038) and lower total motile sperm count (median 7.0 million vs 34.7 million, P = 0.001) compared to men without hyperprolactinemia. 43.1% of men with hyperprolactinemia had oligospermia vs 21.5% of men without hyperprolactinemia (P<0.001). Univariable analysis demonstrated that men with elevated luteinizing hormone (LH) (OR 1.077, P = 0.001) and follicle-stimulating hormone (FSH) (OR 1.032, P = 0.002) were more likely to have hyperprolactinemia. Men with oligospermia were more likely to have hyperprolactinemia (OR 2.334, P = 0.004). On multivariable analysis, neither hormone parameters nor oligospermia were associated with elevated prolactin (P>0.05). Of the 65 men with hyperprolactinemia, 11 (17%) were diagnosed with a prolactinoma, resulting in an overall prevalence of 11 in 3101 (0.35%). CONCLUSION: The overall prevalence of prolactinoma in our cohort of men undergoing fertility evaluation was 35-fold higher than the prevalence in the general male population.

Prolactin Response to Metformin in Cabergoline-Resistant Prolactinomas: A Pilot Study.

INTRODUCTION: Cabergoline is the treatment of choice for prolactinomas. However, 10-20% of prolactinomas are resistant to cabergoline. Metformin, a biguanide widely used in the treatment of diabetes mellitus, has been shown to reduce prolactin secretion in various pituitary tumor-cell lineages both in vitro and in vivo and in human pituitary adenomas in vitro. The aim of this study is to test the effects of metformin addition to cabergoline treatment on prolactin levels in patients with resistant prolactinomas. SUBJECTS AND METHODS: This is a prospective study performed in an outpatient clinic in a reference center. Ten adult patients (26-61 years) with prolactinomas (7 M), persistent hyperprolactinemia (38-386 ng/mL) under cabergoline treatment (2-7 mg/week) for at least 6 months (6-108 months), features of metabolic syndrome, and not taking metformin were included. Metformin (1.0-2.5 g v.o./day) was given according to patients' tolerance. Cabergoline doses were kept unchanged. Serum prolactin levels were measured before and after short- (30-60 days) and long-term (120-180 days) metformin treatment. RESULTS: Mean prolactin levels did not show any significant changes (148 ± 39 vs. 138 ± 42 vs. 133 ± 39 ng/mL, before, at 30-60 days, and at 120-180 days, respectively, p = 0.196) after metformin (mean dose: 1.25 g/day; range: 1.0-2.0 g/day). No patient reached a normal prolactin level during metformin treatment. Two patients were considered partial responders for exhibiting prolactin decreases ≥50% at a single time point during metformin. CONCLUSION: Metformin addition to ongoing high-dose cabergoline treatment in patients with cabergoline-resistant prolactinomas failed to show a consistent inhibitory effect in serum prolactin levels.

Establishment of reference intervals of monomeric prolactin to identify macroprolactinemia in Chinese patients with increased total prolactin.

BACKGROUND: Macroprolactin is responsible for pseudohyperprolactinemia and is a common pitfall of the prolactin immunoassay. We aimed to determine the frequency of macroprolactinemia in Chinese hyperprolactinemic patients using monomeric prolactin discriminated by precipitation with polyethylene glycol (PEG). METHODS: Post-PEG monomeric prolactin gender-specific reference intervals were established for the Elecsys immunoassay method (Roche Diagnostics) using sera from healthy female (n = 120) and male (n = 120) donors. The reference intervals were validated using 20 macroprolactinemic (as assessed by gel filtration chromatography (GFC)) sera samples, and presence of monomeric prolactin was discriminated by GFC. Patients with high total prolactin were then screened by PEG precipitation to analyze macroprolactin. The demographic and biochemical details of patients with true hyperprolactinemia and macroprolactinemia were compared. RESULTS: Reference intervals for monomeric prolactin in females and males were 3.4-18.5 and 2.7-13.1 ng/mL, respectively. Among 1140 hyperprolactinemic patients, macroprolactinemia was identified in 261 (22.9 %) patients while the other 879 (77.1 %) patients were diagnosed with true hyperprolactinemia. Menstrual disturbances were the most common clinical feature in both groups. Galactorrhea, amenorrhea, and visual disturbances occurred more frequently in true hyperprolactinemic patients (P < 0.05). CONCLUSIONS: The prevalence of macroprolactin in Chinese patients with hyperprolactinemia was described for the first time. Monomeric prolactin concentration, along with a reference interval screening with PEG precipitation, provides a diagnostic approach for hyperprolactinemia with improved accuracy.

Distribution of Myeloid and Plasmacytoid Dendritic Cell Subpopulations in Peripheral Blood of Hyperprolactinemic Women.

Dendritic cells (DCs) play key roles in regulating the immune response using the specialized function of processing and presenting antigens. Prolactin (PRL), a hormone produced by the pituitary gland, participates in DC maturation and function. The present study was aimed to determine the frequencies of peripheral blood DC subpopulations of myeloid DC (MDC) and plasmacytoid DC (PDC) in hyperprolactinemic (HPRL) women compared to normal healthy volunteers. This study was conducted on 70 women, including 35 HPRL patients and 35 matched healthy controls, whose PRL serum levels were in the normal range (lower than 25 ng/mL). Serum thyroid-stimulating hormone (TSH) levels were measured in both groups as an indicator of normal thyroid function. The electrochemiluminescence immunoassay method was applied to measure the serum levels of TSH and PRL. The frequencies of MDC and PDC in the peripheral blood samples of both groups were determined by flow cytometry. The mean serum PRL levels in the HPRL patients and healthy individuals were 46.41±21.96 and 13.75±11.19, respectively (p<0.0001); however TSH levels in both groups were similar and within the normal range (0.4-4.5 mIU/mL) (p=0.2). The frequencies of both MDC and PDC subpopulations in the peripheral blood of HPRL patients were significantly lower than they were in the healthy controls. However, the ratio of MDCs/PDCs in HPRL patients was not significantly different between the two groups (p=0.8). Our study revealed that an increased level of serum PRL may lead to a reduction in the number of MDC and PDC subpopulations. These results could help clarify the complex relationship between the immune system and the neuroendocrine axis and may be of potential use in understanding the pathogenesis of endocrine and immune disorders.

Prolactin, metabolic and immune parameters in naïve subjects with a first episode of psychosis.

BACKGROUND: Prolactin (Prl) is a pleiotropic hormone initially described for its regulation of lactation in mammals but later associated with metabolic and immune homeostasis, stress, inflammatory response and human behavior. Its regulation through dopamine receptors highlights its importance in psychiatry mostly because hyperprolactinemia is a common secondary side effect of dopamine antagonists. Despite its undeciphered patho-physiological mechanisms, hyperprolactinemia in naïve psychosis patients has been widely described. Its consequences might underlie the increased morbidity and early mortality found in naïve subjects as described in the general population where prolactin values have been correlated with inflammatory, immune and metabolic parameters. METHODS: We aimed to evaluate the correlation between prolactin values and other biochemical parameters (C-reactive Protein-CrP, blood cell count, lipid and hepatic profile, fasting glucose) in a cohort of first episode psychosis naïve subjects (N = 491) stratified by sex. Regression analyses with confounders were performed to evaluate the association. FINDINGS: Prl displayed significant correlations with C-Reactive Protein (CrP), Low-Density Lipoprotein (LDL), Aspartate Transaminase (AST) for females and High-Density Lipoprotein (HDL) and eosinophil count for males. However, and despite previous specific sex correlations, significant associations were described for CrP, HDL, LDL, AST and ALT without sex interaction and despite confounders such as age, Body Mass Index or smoking status. CONCLUSIONS: Our results show a specific relation of Prl with immune and metabolic parameters describing a heterogeneous pattern. Our results suggest that prolactin might underlie the excess of morbidity and early mortality in naïve patients through a specific pathway.

[Hyperprolactinemia and antipsychotics: it's not always what it seems to be]. / Jongeren met hyperprolactinemie bij antipsychoticagebruik: denk aan macroprolactine.

Hyperprolactinemia is a relatively frequent laboratory abnormality (30-80%) as a result of antipsychotics and a reason to reduce or stop them. We describe two youngsters with autism spectrum disorder whose hyperprolactinemia was based on a false-positive laboratory finding due to macroprolactin. The consequences were: unnecessary endocrinological evaluation including a brain MRI, and undesirable antipsychotic dose reduction. Thus, hyperprolactinemia can be due to a falsely elevated prolactin concentration. There should be an addition to the current guidelines in which a work-up for macroprolactin screening is included.

Altered immunoglobulin G glycosylation in patients with isolated hyperprolactinaemia.

Prolactin is a peptide hormone produced in the anterior pituitary, which increase in several physiological and pathological situations. It is unclear if hyperprolactinaemia may affect glycosylation of immunoglobulin G (IgG). Twenty-five patients with hyperprolactinemia and 22 healthy control subjects were included in the study. The groups had similar age and gender distribution. A panel of hormonal and haematological analyses, creatinine, glucose, liver enzymes and immunoglobulins were measured by routine clinical methods. IgG was purified from serum by Protein G Sepharose. Sialic acid was released from IgG by use of neuraminidase followed by quantification on high performance anion-exchange chromatography with pulsed amperometric detection. Tryptic glycopeptides of IgG was analysed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Hormone and immunoglobulin levels were similar in the two groups, except for IgA and prolactin. Significantly higher IgG1 and IgG2/3 galactosylation was found in the patient group with hyperprolactinaemia compared to controls. (A significant correlation between prolactin and IgG2/3 galactosylation (Rs 0.61, p<0.001) was found for samples with prolactin values below 2000 mIU/L. The relative amount of sialylated and bisecting glycans on IgG did not differ between patients and controls. The four macroprolactinaemic patients showed decreased relative amount of bisecting IgG2/3 glycans. Hyperprolactinaemia was found to be associated with increased galactosylation of IgG1and IgG2/3. This may have impact on IgG interactions with Fc-receptors, complement and lectins, and consequently lead to an altered immune response.

Intracranial Germinoma Misdiagnosed as Hyperthyroidism: A Case Report and Review of the Literature.

Intracranial germ cell tumors (GCTs) are relatively rare, which account for 0.5% of all primary intracranial neoplasms. Intracranial germinomas most commonly occur in the pineal and suprasellar region, making up the majority of all intracranial GCTs. For its diversified clinical manifestations, the diagnosis is easily confused with other diseases. Here, we present a case of a 19-year-old boy with intracranial germinoma who was preliminarily misdiagnosed as hyperthyroidism for the symptoms of weight loss and thyroid dysfunction.

Cardiometabolic Risk Factors in Men with Elevated Macroprolactin Content: A Pilot Study.

BACKGROUND: Macroprolactinemia is a condition associated with the presence of large amounts of high molecular weight complexes of prolactin. Despite high prevalence, clinical significance of macroprolactin remains poorly understood. OBJECTIVE: The aim of this study was to assess cardiometabolic risk in men with isolated macroprolactinemia. METHODS: The study population included 11 men with isolated macroprolactinemia, 14 subjects with monomeric hyperprolactinemia and 14 men with prolactin levels within the reference range. Glucose homeostasis markers, plasma lipids, as well as plasma levels of uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine and 25-hydroxyvitamin D were determined in all included patients. RESULTS: Compared to healthy counterparts, men with isolated macroprolactinemia had higher levels of 2-h postchallenge glucose, hsCRP and fibrinogen, lower levels of 25-hydroxyvitamin D and reduced insulin sensitivity. Patients with monomeric hyperprolactinemia were characterized by increased plasma levels of 2-h postchallenge glucose, triglycerides, uric acid, hsCRP, fibrinogen and homocysteine, reduced insulin sensitivity and decreased plasma concentrations of HDL cholesterol and 25-hydroxyvitamin D. Subjects with isolated macroprolactinemia differed from patients with monomeric hyperprolactinemia in postchallenge plasma glucose, insulin sensitivity, uric acid, hsCRP, fibrinogen, homocysteine and 25-hydroxyvitamin D. In men with monomeric hyperprolactinemia, uric acid, hsCRP, fibrinogen, homocysteine and 25-hydroxyvitamin D, while in men with elevated levels of macroprolactin, uric acid, hsCRP, fibrinogen and 25-hydroxyvitamin D correlated with a content of monomeric prolactin or macroprolactin, respectively, as well as with a degree of insulin sensitivity. CONCLUSIONS: The obtained results suggest that macroprolactinemia may increase cardiometabolic risk but to a lesser extent than monomeric hyperprolactinemia.

The Impact of Ethinyl Estradiol on Metformin Action on Prolactin Levels in Women with Hyperprolactinemia.

BACKGROUND: Metformin reduced prolactin levels only in women with hyperprolactinemia. OBJECTIVE: The purpose of this case-control study was to compare metformin action on lactoctrope function between women receiving oral contraceptive pills and women not using hormonal contraception. METHODS: The study included two groups of matched women with elevated prolactin levels and new-onset prediabetes or diabetes. The first group consisted of 20 women using oral contraceptive pills for at least 12 months before entering the study, while the second group included 20 patients not using any hormonal contraception. Over the whole study period, all women were treated with metformin (1.7-3 g daily). Circulating levels of glucose, insulin, prolactin, thyrotropin, free thyroid hormones, adrenocorticotropic hormone, gonadotropins and insulin-like growth factor-1 were measured at the beginning and at the end of the study (16 weeks later). RESULTS: Thirty-eight patients completed the study. Metformin reduced plasma glucose levels and improved insulin sensitivity but the latter effect was stronger in women receiving oral contraceptive pills than in women not using any contraception. Although metformin treatment decreased plasma prolactin levels in both study groups, this effect was stronger in women taking oral contraceptive pills. Only in this group of women, metformin increased plasma luteinizing hormone levels. The changes in plasma prolactin correlated with their baseline insulin sensitivity and the effect of metformin on insulin sensitivity. Metformin did not affect plasma levels of thyrotropin, free thyroxine, free triiodothyronine, follicle-stimulating hormone, adrenocorticotropic hormone and insulin-like growth factor-1. CONCLUSIONS: The obtained results suggest that the effect of metformin on overactive lactotropes depends on estrogen levels.

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.