The diagnosis and prevalence of hypoprolactinemia in patients with panhypopituitarism and the effects on depression and sexual functions

PURPOSE

We aimed to investigate the prevalence and the diagnostic criteria of hypoprolactinemia in patients with panhypopituitarism and the effects of hypoprolactinemia on depression and sexual functions.

MATERIALS AND METHODS

Forty-eight patients with panhypopituitarism and 20 healthy volunteers were included. Basal hormone levels were measured and a TRH stimulation test was performed. For the evaluation of sexual functions, questionnaries of Female Sexual Functional Index (FSFI) for females and International Erectile Functional Index for males were performed to the subjects. Depressive symptoms were evaluated by Beck Depression Envontory score (BDI-II).

RESULTS

The peak PRL response to TRH stimulation test at 5th percentile in the control group was 18.6 ng/ml in males and 41.6 ng/ml in females and accepted as the cut-offs for sufficient response of PRL. Prolactin was insufficient in 42(87.5%) patients. A basal PRL level of ≤ 5.7 ng/ml in males and 7.11 ng/ml in females was 100% specific in predicting an inadequate response to TRH stimulation test with 80% and 70% sensitivity respectively. A basal PRL level of ≥ 8.5 ng/dl in males was 100% specific and 76% sensitive, and in females a level of ≥ 15.2 ng/dl was 96% specific and 66% sensitive in predicting an adequate response to TRH. PRL deficient patients with panhypopituitarism had higher depression scores compared to the controls, lower sexual function scores in males.

CONCLUSION

PRL deficiency is prevalent among individuals with panhypopituitarism, with the potential to result in elevated depression scores in both sexes and impaired sexual functions in males. A basal PRL level seems to be sufficient for the diagnosis of hypoprolactinemia in routine clinical practice.

Pitfalls in the lab assessment of hypopituitarism

The diagnostic approach to hypopituitarism involves many disciplines. Clinical symptoms rarely are specific. Imaging techniques are helpful but cannot prove the specific functional defects. Therefore, the definitive diagnosis of pituitary insufficiency is largely based on laboratory tests. However, also laboratory methods come with inherent limitations, and it is essential for the clinician to know and recognize typical pitfalls. Most factors potentially impairing the quality of hormone measurements are introduced in the preanalytical phase, i.e. before the hormones are measured by the laboratory. For example, the timing of blood drawing with respect to circadian rhythm, stress, and medication can have an influence on hormone concentrations. During the actual analysis of the hormones, cross-reactions with molecules present in the sample presenting the same or similar epitopes than the intended analyte may affect immunoassays. Interference can also come from heterophilic or human anti-animal antibodies. Unexpected problems can also be due to popular nutritional supplements which interfere with the measurement procedures. An important example in this respect is the interference from biotin. It became only clinically visible when the use of this vitamin became popular among patients. The extreme serum concentrations reached when patients take it as a supplement can lead to incorrect measurements in immunoassays employing the biotin-streptavidin system. To some extent, hormone analyses using liquid chromatography mass spectrometry (LCMS) can overcome problems, although availability and cost-effectiveness of this method still imposes restrictions. In the post-analytical phase, appropriateness of reference intervals and cut-offs with respect to the specific analytical method used is of outmost importance. Furthermore, for interpretation, additional biological and pharmacological factors like BMI, age and concomitant diseases must be considered to avoid misinterpretation of the measured concentrations. It is important for the clinician and the laboratory to recognize when one or more laboratory values do not match the clinical picture. In an interdisciplinary approach, the search for the underlying cause should be initiated.

Diagnostic value of standard deviation score of log-transformed serum dehydroepiandrosterone sulfate in patients with hypothalamic-pituitary-adrenal axis insufficiency

Serum dehydroepiandrosterone sulfate (DHEA-S) levels reflect the state of adrenocorticotropic hormone (ACTH) secretion. However, it is difficult to use serum DHEA-S to diagnose hypothalamic-pituitary-adrenal (HPA) axis insufficiency due to its non-normal and highly skewed distribution. In this study, we focused on HPA insufficiency caused by hypothalamic and/or pituitary dysfunction and evaluated the usefulness of the standard deviation score of log-transformed DHEA-S (ln DHEA-S SD score), which was calculated from the established age- and sex-specific reference values. We retrospectively reviewed the medical records of 94 patients suspected of having HPA insufficiency, in whom serum DHEA-S measurement and the rapid ACTH stimulation test were performed, and included 65 patients who met our criteria in this study. The ln DHEA-S SD scores were distributed more normally than measured DHEA-S levels and were significantly higher in patients with a peak cortisol level ≥18 μg/dL than in those below this value, suggesting that this score is a legitimate and strong indicator of adrenocortical function. The optimal cut-off value for impaired HPA function was -0.853, with a sensitivity of 70.3% and a specificity of 100%. Among the 37 patients whose peak cortisol levels were below 18 μg/dL, 11 patients with ln DHEA-S scores ≥-0.853 exhibited significantly higher basal ACTH and basal and peak cortisol levels than the 26 patients with scores <-0.853. Thus, this score plays a supportive role in evaluating HPA axis function, particularly in patients with borderline cortisol responses to ACTH.

The hypothalamus-pituitary-thyroid (HPT)-axis and its role in physiology and pathophysiology of other hypothalamus-pituitary functions

The hypothalamus-pituitary-thyroid axis is one of several hormone regulatory systems from the hypothalamus to the pituitary and ultimately to the peripheral target organs. The hypothalamus and the pituitary gland are in close anatomical proximity at the base of the brain and extended through the pituitary stalk to the sella turcica. The pituitary stalk allows passage of stimulatory and inhibitory hormones and other signal molecules. The target organs are placed in the periphery and function through stimulation/inhibition by the circulating pituitary hormones. The several hypothalamus-pituitary-target organ axis systems interact in very sophisticated and complicated ways and for many of them the interactive and integrated mechanisms are still not quite clear. The diagnosis of central hypothyroidism is complicated by itself but challenged further by concomitant affection of other hypothalamus-pituitary-hormone axes, the dysfunction of which influences the diagnosis of central hypothyroidism. Treatment of both the central hypothyroidism and the other hypothalamus-pituitary axes also influence the function of the others by complex mechanisms involving both central and peripheral mechanisms. Clinicians managing patients with neuroendocrine disorders should become aware of the strong integrative influence from each hypothalamus-pituitary-hormone axis on the physiology and pathophysiology of central hypothyroidism. As an aid in this direction the present review summarizes and highlights the importance of the hypothalamus-pituitary-thyroid axis, pitfalls in diagnosing central hypothyroidism, diagnosing/testing central hypothyroidism in relation to panhypopituitarism, pointing at interactions of the thyroid function with other pituitary hormones, as well as local hypothalamic neurotransmitters and gut-brain hormones. Furthermore, the treatment effect of each axis on the regulation of the others is described. Finally, these complicating aspects require stringent diagnostic testing, particularly in clinical settings with lower or at least altered à priori likelihood of hypopituitarism than in former obvious clinical patient presentations.

High-intensity interval exercise test stimulates growth hormone secretion in children

BACKGROUND

exercise stimulates growth hormone (GH) secretion and may serve as a promising physiological test for the diagnosis of GH deficiency. However, exercise standardization for a feasible GH test is still lacking. The aim of the present study was to examine the GH secretion to high intensity interval exercise.

METHODS

Seventeen children (12.4 ± 2.6 years) with impaired growth rate performed high-intensity interval exercise test (HIIE) that included 10 intervals of 15 s all out pedaling against resistance determined by age, sex and weight on a cycle ergometer with 1-min active rest between each interval. Power output measurements were collected during the test. Blood samples were collected before, immediately after, 30, 45, and 60min after the beginning of the exercise test. GH response was compered to pharmacological provocation test (clonidine or glucagon).

RESULTS

HIIE led to a significant increase in GH levels (p < 0.001), with high correlation to GH response following pharmacological stimulation (r = 0.82, r = 0.80 for clonidine and glucagon respectively, p < 0.001) A significant correlation was found between mean peak power to body weight and the GH response (r = 0.50, p = 0.04). 83% of the participants who reached peak power > 10 watts/kg had normal GH secretion.

CONCLUSIONS

HIIE is a brief and individualized exercise protocol that may be used as a physiological provocation test for GH secretion. There might be a minimum of anaerobic power needed to induce adequate GH response during HIIE.

Machine-Learning Prediction of Postoperative Pituitary Hormonal Outcomes in Nonfunctioning Pituitary Adenomas: A Multicenter Study

OBJECTIVE

No accurate predictive models were identified for hormonal prognosis in non-functioning pituitary adenoma (NFPA). This study aimed to develop machine learning (ML) models to facilitate the prognostic assessment of pituitary hormonal outcomes after surgery.

METHODS

A total of 215 male patients with NFPA, who underwent surgery in four medical centers from 2015 to 2021, were retrospectively reviewed. The data were pooled after heterogeneity assessment, and they were randomly divided into training and testing sets (172:43). Six ML models and logistic regression models were developed using six anterior pituitary hormones.

RESULTS

Only thyroid-stimulating hormone (p < 0.001), follicle-stimulating hormone (p < 0.001), and prolactin (PRL; p < 0.001) decreased significantly following surgery, whereas growth hormone (GH) (p < 0.001) increased significantly. The postoperative GH (p = 0.07) levels were slightly higher in patients with gross total resection, but the PRL (p = 0.03) level was significantly lower than that in patients with subtotal resection. The optimal model achieved area-under-the-receiver-operating-characteristic-curve values of 0.82, 0.74, and 0.85 in predicting hormonal hypofunction, new deficiency, and hormonal recovery following surgery, respectively. According to feature importance analyses, the preoperative levels of the same type and other hormones were all important in predicting postoperative individual hormonal hypofunction.

CONCLUSION

Fluctuation in anterior pituitary hormones varies with increases and decreases because of transsphenoidal surgery. The ML models could accurately predict postoperative pituitary outcomes based on preoperative anterior pituitary hormones in NFPA.

Lower Oxytocin Levels Are Associated with Lower Bone Mineral Density and Less Favorable Hip Geometry in Hypopituitary Men

INTRODUCTION

Hypopituitary patients are at risk for bone loss. Hypothalamic-posterior pituitary hormones oxytocin and vasopressin are anabolic and catabolic, respectively, to the skeleton. Patients with hypopituitarism may be at risk for oxytocin deficiency. Whether oxytocin and/or vasopressin contribute to impaired bone homeostasis in hypopituitarism is unknown.

OBJECTIVES

To determine the relationship between plasma oxytocin and vasopressin levels and bone characteristics (bone mineral density [BMD] and hip structural analysis [HSA]) in patients who have anterior pituitary deficiencies only (APD group) or with central diabetes insipidus (CDI group).

METHODS

This is a cross-sectional study. Subjects included 37 men (17 CDI and 20 APD), aged 20-60 years. Main outcome measures were fasting plasma oxytocin and vasopressin levels, and BMD and HSA using dual X-ray absorptiometry.

RESULTS

Mean BMD and HSA variables did not differ between the CDI and APD groups. Mean BMD Z-scores at most sites were lower in those participants who had fasting oxytocin levels below, rather than above, the median. There were positive associations between fasting oxytocin levels and (1) BMD Z-scores at the spine, femoral neck, total hip, and subtotal body and (2) favorable hip geometry and strength variables at the intertrochanteric region in CDI, but not APD, participants. No associations between vasopressin levels and bone variables were observed in the CDI or ADP groups.

CONCLUSIONS

This study provides evidence for a relationship between oxytocin levels and BMD and estimated hip geometry and strength in hypopituitarism with CDI. Future studies will be important to determine whether oxytocin could be used therapeutically to optimize bone health in patients with hypopituitarism.

Masked type 1 diabetes mellitus (T1DM) unveiled by glucocorticoid replacement: a case of simultaneous development of T1DM and hypophysitis in an elderly woman

As a rare condition characterized by inflammation of the pituitary gland, hypophysitis usually results in hypopituitarism and pituitary enlargement. The most critical outcome of hypopituitarism is caused by secondary adrenal insufficiency. Glucocorticoid deficiency is a life-threatening condition, and patients who develop this deficiency require prompt diagnosis and treatment. However, a delayed diagnosis of hypopituitarism may occur due to its non-specific clinical manifestations. A common presenting sign of glucocorticoid deficiency is hypoglycemia. The amelioration of hyperglycemia has been observed in diabetic patients with adrenal insufficiency. We report the case of a 70-year-old Japanese woman who had suffered from fatigue and anorexia for several months; she was admitted based on refractory hyponatremia (sodium 125-128 mEq/L) and hypoglycemia (glucose 58-75 mg/dL). Laboratory findings and magnetic resonance imaging findings led to the diagnosis of panhypopituitarism caused by autoimmune hypophysitis. After receiving 10 mg/day of hydrocortisone, the patient developed severe hyperglycemia (glucose >500 mg/dL). Undetectable C-peptide levels and positive results of both insulinoma-associated antigen-2 antibodies and insulin autoantibodies indicated that she had experienced a recent onset of type 1 diabetes. The pathophysiological process indicated that overt hyperglycemia could be masked by the deficient action of glucocorticoids even in a diabetic patient with endogenous insulin deficiency. This uncommon case reinforces the importance of the prompt diagnosis and treatment of hypopituitarism. Clinicians should remain aware of the possibility of hidden diabetes when treating hypoglycemia in patients with adrenal insufficiency.

Central diabetes insipidus unveiled by glucocorticoid therapy in a patient with an empty sella: A case report and literature review

RATIONALE

Some diseases contribute to hypopituitarism without clinical manifestations and the glucocorticoid therapy may unveil central diabetes insipidus. The condition is rare and usually causes problems for clinical physicians.

PATIENT CONCERNS

A 59-year-old woman presented to our hospital due to facial numbness and persistent eyelid heaviness.

DIAGNOSIS

Physical examination and cerebrospinal fluid examination supported a diagnosis of Guillain-Barre[Combining Acute Accent] syndrome. Magnetic resonance imaging showed an empty sella. Hormone test indicated hypopituitarism.

INTERVENTIONS

The patient received intravenous immunoglobulin and glucocorticoid. Central diabetes insipidus appeared after 20 days. Subsequently, the patient was prescribed 1-desamino-8-D-arginine vasopressin and prednisone.

OUTCOMES

During 6 months' follow-up, the patient's urine output was gradually reduced to normal level.

LESSONS

This case indicated that hypopituitarism may be caused by an empty sella and be masked by adrenal insufficiency. Central diabetes insipidus may present after glucocorticoid therapy.

Metabolic syndrome and its components in adult hypopituitary patients

PURPOSE

To evaluate the prevalence of metabolic syndrome (MetS) and its components in adult hypopituitary patients.

PATIENTS AND METHODS

Retrospective, cross-sectional analysis of a cohort of hypopituitary adult patients followed in a single reference center for pituitary diseases. MetS was defined by the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria. Patients with 18 years or older, presenting two or more anterior pituitary deficiencies associated or not with diabetes insipidus (DI), were included, while patients with hypopituitarism due to Acromegaly or Cushing's disease were excluded.

RESULTS

We studied 99 hypopituitary patients (52 males, mean age 50.1 ± 16.3 years, mean age at diagnosis 33.7 ± 17.6 years) who have been followed for a mean time of 15.9 ± 10.1 years. Hypothalamic-pituitary tumors and non-tumoral etiologies were observed in 53.4% and 46.6% of the cases, respectively. FSH/LH, GH, TSH, ACTH deficiency and DI was present in 99%, 98.6%, 96%, 81.8%, and 23.2%, respectively. The prevalence of MetS was 39.4% and was significantly higher in patients older than 50 years (p = 0.02), overweight/obese (p < 0.001), with hypopituitarism diagnosed in adult life (p = 0.02), who did not replace GH (p = 0.004) and in smokers (p = 0.007). In the logistic regression model, body mass index (BMI) and GH replacement were significantly associated with the presence of MetS. Reduced HDL cholesterol was the most prevalent component of MetS in hypopituitary patients.

CONCLUSIONS

MetS is a common finding in adult hypopituitary patients, which is mainly influenced by increased BMI and untreated GH deficiency. Trial Registration number (Plataforma Brasil): CAAE 51008815.2.0000.0096 (May 31, 2017) .

Cardiovascular effects of growth hormone (GH) treatment on GH-deficient adults: a meta-analysis update

BACKGROUND

It is still unclear whether growth hormone (GH) replacement is able to improve cardiovascular parameters in adults with GH deficiency (AGHD) from the updated clinical trials reported to date.

METHODS AND RESULTS

We systematically reviewed clinical trials of GH treatment on AGHD patients in recent decade, and evaluated the effects of GH on cardiovascular parameters assessed by echocardiography. 11 clinical trials were identified in 3 bibliographic databases. We conducted a combined analysis of effects on four aspects: General indicators: baseline heart rate (BHR), peak heart rate (PHR), systolic blood pressure (SBP), diastolic blood pressure (DBP); Cardiac structure: left ventricular end diastolic volume (LVEDV), left ventricular end systolic volume (LVESV), left ventricular interventricular septum (LVIS), left ventricular mass (LVM), left ventricular posterior wall (LVPW); Cardiovascular function: deceleration time of E wave (DT), E/A ratio (E/A), ejection fraction (EF), NT-BNP; Life quality: peak VO₂, VE/VCO₂ slope. Overall effect size was used to evaluate significance, and weighted mean difference after GH treatment was given to appreciate size of the effect. GH treatment was associated with a significant increase in BHR (3.03[2.00, 4.06]), LVIS (0.50[0.43, 0.57]), LVPW (0.50[0.43, 0.57]), and EF (2.12[1.34, 2.90]). Overall effect sizes were negative significant for DBP (- 1.19[- 2.33, - 0.05]), LVEDV (- 9.84[- 16.53, - 3.15]), NT-BNP (- 206.34[- 308.95, - 103.72]), and VE/VCO2 slope (- 2.31[- 2.92, - 1.71]).

CONCLUSIONS

As assessed by echocardiography, GH administration may improve the general vital signs and life quality of AGHD patients, based on the positive effect on BHR and negative effects on DBP and VE/VCO₂ slope. Also, GH treatment would influence the structure of heart with positive effects on LVIS, LVPW and negative effect on LVEDV, which together with the increase of EF and decrease of NT-BNP, then resulting in improving the systolic function of AGHD patients.

Evaluation of oxidative stress effects on different macromolecules in adult growth hormone deficiency

Adult growth hormone deficiency (GHD) is being increasingly recognized to cause premature mortality exacerbated by oxidative stress. A case-control observational study has been performed with the primary objective of evaluating new parameters of oxidative stress and macromolecular damage in adult GHD subjects: serum nitrotryptophan; Total Antioxidant Capacity expressed as LAG time; urinary hexanoil-lysine; urinary dityrosine and urinary 8-OH-deoxyguanosine. GHD was diagnosed using Growth Hormone-Releasing Hormone 50μg iv+arginine 0,5 g/Kg test, with a peak GH response <9 μg /L when BMI was <30 kg/m2 or <4 μg/L when BMI was >30 kg/m2. Patients affected by adult GHD were divided into three groups, total GHD (n = 26), partial GHD (n = 25), and controls (n = 29). Total Antioxidant Capacity, metabolic and hormonal parameters have been determined in separate plasma samples; nitrotryptophan in serum samples; hexanoil-lysine, dityrosine, 8-OH-deoxyguanosine in urine samples. Assessment of hexanoil-lysine exhibited a trend to increase in comparing total GHD vs partial and controls, although not significant. Values of 8-OH-deoxyguanosine did not significantly differ among the three groups. Significant lower levels of dityrosine in partial GHD vs total and controls were found. No significant difference in nitrotriptophan serum levels was found, while significantly greater values of Total Antioxidant Capacity were showed in total and partial GHD vs controls. Thus, our result confirm that oxidative stress is increased both in partial and total adult GHD. The lack of compensation by antioxidants in total GHD may be connected to the complications associated to this rare disorder.

Hypopituitarism manifesting after invasive dental treatment in a patient with carcinoma of the tongue: a case report

BACKGROUND

The symptoms of hypopituitarism are not usually discussed in the clinical setting of oral surgery.

CASE PRESENTATION

We herein report a case of hypopituitarism that became evident after biopsy and extraction of several teeth in a 68-year-old man with tongue cancer. Three days after biopsy, the patient developed nausea and vomiting, and his serum sodium had fallen to 124 mEq/L. His serum cortisol concentration was low. Although the plasma concentration of adrenocorticotropic hormone (ACTH) was within the normal range, ACTH stimulation testing showed a lack of cortisol response. Given these findings, we suspected secondary adrenal insufficiency. To investigate the cause of secondary adrenal insufficiency, MRI of the head was performed, which revealed pituitary gland atrophy. The results of pituitary anterior lobe hormone-stimulation tests were compatible with hypopituitarism. Thirty days after biopsy, partial tongue resection was successfully performed under general anesthesia with perioperative hydrocortisone supplementation.

CONCLUSIONS

We must be aware of various signs of hypopituitarism when we perform invasive dental treatment.

The Optimized Calculation Method for Insulin Dosage in an Insulin Tolerance Test (ITT): A Randomized Parallel Control Study

Objective: To explore the most suitable calculation method for insulin dosage in an insulin tolerance test (ITT) and to evaluate the clinical application value of the optimization coefficient (γ). Methods: In this study, 140 adult patients with congenital growth hormone deficiency (GHD) or acquired hypopituitarism were randomized into the following two groups: the conventional group (n = 70) and the optimized group (n = 70). Oral glucose tolerance tests (OGTTs), insulin release tests (IRTs), and ITTs were conducted. For ITTs, insulin doses were the product of body weight (kg) and related coefficient (0.15 IU/kg for the control group and γ IU/kg for the optimized group, respectively). Notably, γ was defined as -0.034 + 0.000176 × AUC_INS + 0.009846 × BMI, which was based on our previous study. Results: In the ITTs, the rate of achieving adequate hypoglycemia with a single insulin dose was significantly higher for the optimized group compared with the conventional group (92.9 vs. 60.0%, P < 0.001). The optimized group required higher initial doses of insulin (0.23 IU/kg). Meanwhile, the two groups did not differ significantly in their nadir blood glucose (1.9 vs. 1.9 mmol/L, P = 0.828). Conclusion: This study confirmed that the proposed optimized calculation method for insulin dosage in ITTs led to more efficient hypoglycemia achievement, without increasing the incidence of serious adverse events.

Ghrelin Does Not Directly Stimulate Secretion of Glucagon-like Peptide-1

CONTEXT

The gastrointestinal hormone ghrelin stimulates growth hormone secretion and appetite, but recent studies indicate that ghrelin also stimulates the secretion of the appetite-inhibiting and insulinotropic hormone glucagon-like peptide-1 (GLP-1).

OBJECTIVE

To investigate the putative effect of ghrelin on GLP-1 secretion in vivo and in vitro.

SUBJECTS AND METHODS

A randomized placebo-controlled crossover study was performed in eight hypopituitary subjects. Ghrelin or saline was infused intravenously (1 pmol/min × kg) after collection of baseline sample (0 min), and blood was subsequently collected at time 30, 60, 90, and 120 minutes. Mouse small intestine was perfused (n = 6) and GLP-1 output from perfused mouse small intestine was investigated in response to vascular ghrelin administration in the presence and absence of a simultaneous luminal glucose stimulus. Ghrelin receptor expression was quantified in human (n = 11) and mouse L-cells (n = 3) by RNA sequencing and RT-qPCR, respectively.

RESULTS

Ghrelin did not affect GLP-1 secretion in humans (area under the curve [AUC; 0-120 min]: ghrelin infusion = 1.37 ± 0.05 min × nmol vs. saline infusion = 1.40 ± 0.06 min × nmol [P = 0.63]), but induced peripheral insulin resistance. Likewise, ghrelin did not stimulate GLP-1 secretion from the perfused mouse small intestine model (mean outputs during baseline/ghrelin infusion = 19.3 ± 1.6/25.5 ± 2.0 fmol/min, n = 6, P = 0.16), whereas glucose-dependent insulinotropic polypeptide administration, used as a positive control, doubled GLP-1 secretion (P < 0.001). Intraluminal glucose increased GLP-1 secretion by 4-fold (P < 0.001), which was not potentiated by ghrelin. Finally, gene expression of the ghrelin receptor was undetectable in mouse L-cells and marginal in human L-cells.

CONCLUSIONS

Ghrelin does not interact directly with the L-cell and does not directly affect GLP-1 secretion.

Low Plasma Oxytocin Levels and Increased Psychopathology in Hypopituitary Men With Diabetes Insipidus

CONTEXT

Oxytocin (OT) and vasopressin share anatomical pathways of synthesis and secretion, and patients with central diabetes insipidus (CDI) presumably are at risk for OT deficiency. However, an OT-deficient state in hypopituitary patients has not been established.

OBJECTIVES

We hypothesized that men with CDI compared to patients with similar anterior pituitary deficiencies (APD) but no CDI and healthy controls (HC) of similar age and body mass index, would have lower plasma OT levels, associated with increased psychopathology.

DESIGN

Cross-sectional.

SETTING

Clinical research center.

PARTICIPANTS

Sixty-two men (20 CDI, 20 APD, 22 HC), age 18 to 60 years.

INTERVENTIONS

Frequent sampling of blood every 5 minutes for OT over 1 hour and validated questionnaires to assess psychopathology.

MAIN OUTCOMES

Pooled plasma OT levels; depressive, anxiety, and alexithymia symptoms; and quality of life.

RESULTS

The mean 1-hour pool of fasting OT levels was lower in CDI compared with APD and HC (P = 0.02 and P = 0.009, respectively), with no differences between APD and HC (P = 0.78). Symptoms of depression, anxiety, and alexithymia were more pronounced in CDI than in HC (P = 0.001, P = 0.004, and P = 0.02, respectively). Although CDI and APD reported worse physical health compared with HC (P = 0.001 and P = 0.005) with no differences between APD and CDI, only CDI reported worse mental health compared with HC (P = 0.009).

CONCLUSIONS

We have demonstrated low plasma OT levels and increased psychopathology in hypopituitary men with CDI, suggestive of a possible OT-deficient state. Larger studies of both sexes are required to confirm these findings and clinically characterize hypopituitary patients with OT deficiency.

In primary care, is measuring free-thyroxine plus thyroid-stimulating hormone to detect hypopituitarism cost-effective? A cost utility analysis using Markov chain models

OBJECTIVE

We examined whether it is cost-effective to measure free thyroxine (FT4) in addition to thyrotropin (thyroid-stimulating hormone (TSH)) on all requests for thyroid function tests from primary care on adult patients.

BACKGROUND

Hypopituitarism occurs in about 4 people per 100 000 per year. Loss of thyrotropin (TSH) secretion may lead to secondary hypothyroidism with a low TSH and low FT4, and this pattern may help to diagnose hypopituitarism that might otherwise be missed.

DESIGN

Markov model simulation.

PRIMARY OUTCOME MEASURE

Incremental cost-effectiveness ratio (ICER), the ratio of cost in pounds to benefit in quality-adjusted life years of this strategy.

RESULTS

The ICER for this strategy was £71 437. Factors with a large influence on the ICER were the utilities of the treated hypopituitary state, the likelihood of going to the general practitioner (GP) and of the GP recognising a hypopituitary patient. The ICER would be below £20 000 at a cost to the user of an FT4 measurement of £0.61.

CONCLUSION

With FT4 measurements at their present cost to the user, routine inclusion of FT4 in a thyroid hormone profile is not cost-effective.

Panhypopituitarism- An unusual presenation of tuberculous meningitis

Pituitary gland involvement is a very rare entity of central nervous system tuberculosis. Tubercular meningitis (TBM) is a chronic meningitis on hypothalamic-pituitary axis which causes high morbidity and mortality hence it is the most dreaded form of extra pulmonary tuberculosis. Here we report a case of 24 year old female presenting with three months history of fever and headache along with altered sensorium since four days. There was also complain of secondary amenorrhea and generalised apathy. Neuroimaging revealed subependymal tuberculomas with meningitis and obstructive hydrocephalus. Cerebrospinal fluid (CSF) examination was also suggestive of tubercular meningitis. Endocrinological investigations showed multiple hormonal deficiencies manifesting as pituitary hypothyroidism, hypocortisolism, hypogonadotropic hypogonadism, and hypoprolactinemia. Anti-tuberculosis treatment was started, and it led to significant improvement in the general condition of the patient.

Acipimox Acutely Increases GLP-1 Concentrations in Overweight Subjects and Hypopituitary Patients

CONTEXT

Glucagon-like peptide-1 (GLP-1) is an incretin hormone used therapeutically in type 2 diabetes and obesity. The interplay between ambient free fatty acids (FFAs) and GLP-1 remains unclear. Acipimox suppresses adipose tissue lipolysis via activation of the PUMA-G (also known as HCA2 and GPR109a) receptor.

OBJECTIVE

To investigate whether lowering of serum FFA level with acipimox affects GLP-1 secretion.

DESIGN

Two randomized crossover studies were performed in human subjects. Rat intestine was perfused intra-arterially and intraluminally, and l-cells were incubated with acipimox.

PARTICIPANTS

The participants were healthy overweight subjects and hypopituitary adult patients.

INTERVENTIONS

The overweight participants received acipimox 250 mg 60 minutes before an oral glucose test. The hypopituitary patients received acipimox 250 mg 12, 9, and 2 hours before and during the metabolic study day, when they were studied in the basal state and during a hyperinsulinemic euglycemic clamp.

RESULTS

Acipimox suppressed FFA but did not affect insulin in the clinical trials. In overweight subjects, the GLP-1 increase after the oral glucose tolerance test (area under the curve) was more than doubled [4119 ± 607 pmol/L × min (Acipimox) vs 1973 ± 375 pmol/L × min (control), P = 0.004]. In hypopituitary patients, acipimox improved insulin sensitivity (4.7 ± 0.8 mg glucose/kg/min (Acipimox) vs 3.1 ± 0.5 mg glucose/kg/min (control), P = 0.005], and GLP-1 concentrations increased ~40%. An inverse correlation between FFA and GLP-1 concentrations existed in both trials. In rat intestine, acipimox did not affect GLP-1 secretion, and l-cells did not consistently express the putative receptor for acipimox.

CONCLUSIONS

Acipimox treatment increases systemic GLP-1 levels in both obese subjects and hypopituitary patients. Our in vitro data indicate that the underlying mechanisms are indirect.

Hypothalamic-pituitary axis irradiation dose thresholds for the development of hypopituitarism in adult-onset gliomas

BACKGROUND

Childhood brain tumour survivors who receive cranial radiotherapy undergo regular surveillance for the development ofhypothalamic-pituitary (HP) axis dysfunction. Much less attention has been given to radiation-induced hypopituitarism in patients with malignant brain tumours of adult onset.

DESIGN

Retrospective cohort study.

PATIENTS/MEASUREMENTS

We assessed the effects of cranial radiotherapy (cXRT) on pituitary function in 58 adults (32 male) with gliomas distant to the HP axis. The XRT dose exposure at the HP axis was correlated with individual axis dysfunction to establish dose thresholds.

RESULTS

Mean age at cXRT was 41.2 ± 10.9 years and duration of endocrine follow-up 8.2 ± 5.2 years. Mean XRT dose to the HP axis was 35.9 ± 15.5 Gy. Overall prevalence of radiation-induced hypopituitarism was 84.5%. GH, LH/FSH, ACTH and TSH deficiency were present in 82.8%, 20.7%, 19% and 6.9% of patients, respectively. Hyperprolactinaemia was noted in 10.3% (n = 6) and was persistent in one case. GH deficiency and "any degree of hypopituitarism" positively correlated with the radiotherapy dose to the hypothalamic-pituitary axis. HP axis XRT dose thresholds for the development of GHD, LH/FSH, ACTH and TSH deficiency were established at 10, 30, 32 and 40.8 Gy, respectively. A gradual increase in the prevalence of all anterior pituitary hormone deficits was observed throughout the follow-up period.

CONCLUSIONS

Hypopituitarism post-cXRT in adults with gliomas is a frequent, progressive and dose-dependent phenomenon. Dose thresholds suggest long-term endocrine surveillance is important where the HP axis XRT dose is higher than 30 Gy. Identification of deficits to allow early and appropriate hormone replacement therapy is important to improve well-being in these individuals with limited prognosis.

Pituitary deficiency and precocious puberty after childhood severe traumatic brain injury: a long-term follow-up prospective study

Objectives Childhood traumatic brain injury (TBI) is a public health issue. Our objectives were to determine the prevalence of permanent pituitary hormone deficiency and to detect the emergence of other pituitary dysfunctions or central precocious puberty several years after severe TBI. Design Follow-up at least 5 years post severe TBI of a prospective longitudinal study. Patients Overall, 66/87 children, who had endocrine evaluation 1 year post severe TBI, were included (24 with pituitary dysfunction 1 year post TBI). Main outcome measures In all children, the pituitary hormones basal levels were assessed at least 5 years post TBI. Growth hormone (GH) stimulation tests were performed 3-4 years post TBI in children with GH deficiency (GHD) 1 year post TBI and in all children with low height velocity (<-1 DS) or low IGF-1 (<-2 DS). Central precocious puberty (CPP) was confirmed by GnRH stimulation test. Results Overall, 61/66 children were followed up 7 (5-10) years post TBI (median; (range)); 17/61 children had GHD 1 year post TBI, and GHD was confirmed in 5/17 patients. For one boy, with normal pituitary function 1 year post TBI, GHD was diagnosed 6.5 years post TBI. 4/61 patients developed CPP, 5.7 (2.4-6.1) years post-TBI. Having a pituitary dysfunction 1 year post TBI was significantly associated with pituitary dysfunction or CPP more than 5 years post TBI. Conclusion Severe TBI in childhood can lead to permanent pituitary dysfunction; GHD and CPP may appear after many years. We recommend systematic hormonal assessment in children 1 year after severe TBI and a prolonged monitoring of growth and pubertal maturation. Recommendations should be elaborated for the families and treating physicians.

Clinical characteristics of non-alcoholic fatty liver disease in Chinese adult hypopituitary patients

BACKGROUND

Patients with hypothalamic-pituitary disease have the feature of central obesity, insulin resistance, and dyslipidemia, and there is increased prevalence of liver dysfunction consistent with non-alcoholic fatty liver disease (NAFLD) in this population. The causes of hypopituitarism in the reported studies varied and combined pituitary hormone deficiency including central diabetes insipidus is much common in this population. This retrospective cross-sectional study was performed to analyze the clinical characteristics and related factors with NAFLD and cirrhosis in Chinese adult hypopituitary/panhypopituitary patients.

AIM

To analyze the clinical characteristics of and related risk factors for NAFLD in Chinese adult hypopituitary patients.

METHODS

Adult Chinese patients with hypopituitarism and/or panhypopituitarism were enrolled at the Pituitary Center of Peking Union Medical College Hospital between August 2012 and April 2018. According to abdominal ultrasonography, these patients were divided into an NAFLD (-) group and an NAFLD (+) group, and the latter was further divided into an NAFLD group and a cirrhotic group. The data, such as patient characteristics, diagnosis, and treatment, were extracted from medical records, and statistical analysis was performed.

RESULTS

A total of 36 male and 14 female adult Chinese patients with hypopituitarism were included in this retrospective study; 43 (87.0%) of these patients exhibited growth hormone (GH) deficiency, and 39 (78.3%) had diabetes insipidus. A total of 27 (54.0%) patients were diagnosed with NAFLD, while seven patients were cirrhotic. No significant differences were noted in serum GH or insulin-like growth factor 1 among patients with cirrhosis, subjects with NAFLD, and those without NAFLD. However, plasma osmolality and serum sodium concentration of the cirrhotic patients were 314.9 mOsm/kgH₂O and 151.0 mmol/L, respectively, which were significantly higher than those of the NAFLD patients (P = 0.036 and 0.042, respectively). Overweight/obesity and insulin resistance were common metabolic disorders in this population. The body mass index (BMI) and homeostasis model assessment of insulin resistance parameters of the cirrhotic patients were 27.7 kg/m² and 9.57, respectively, which were significantly higher than those of the patients without NAFLD (P = 0.011 and 0.044, respectively). A correlation analysis was performed, and fasting insulin concentration was positively associated with plasma osmolality in patients with NAFLD, after adjusting for gender, age, and BMI (r = 0.540, P = 0.046), but no correlation was noted in patients without NAFLD.

CONCLUSION

NAFLD is common in patients with hypopituitarism. Plasma osmolality and serum sodium levels of hypopituitary patients with cirrhosis are higher than those of subjects with NAFLD, and fasting insulin concentration is positively associated with plasma osmolality in patients with NAFLD, which suggests that hyperosmolality might be a contributor to the worsening of NAFLD in hypopituitary patients.