Oxytocin alterations and neurocognitive domains in patients with hypopituitarism

PURPOSE

Oxytocin is a hypothalamus derived, posterior pituitary stored nonapeptide which has gained recent interest as an important neuropsychiatric and metabolic hormone beyond its classic role in lactation and parturition. Hypopituitarism is a heterogenous disorder of derangement in one or more anterior or posterior pituitary hormones. Diagnosis of deficiency and hormone replacement exists to address all relevant axes except for oxytocin. Our study aims to define derangements in oxytocin in a unique population of patients with hypopituitarism and correlate levels with measures of emotional health and quality of life.

METHODS

A cross-sectional, single day study was completed to measure plasma oxytocin levels in a diverse population of patients with hypopituitarism compared to controls. Subjects also completed depression, quality of life and stress-related questionnaires, and emotion recognition tasks.

RESULTS

Thirty-eight subjects completed the study, 18 with hypopituitarism (9 with diabetes insipidus) and 20 controls. After controlling for differences in age, weight and gender, plasma oxytocin levels were highest in subjects with diabetes insipidus compared to control [mean, IQR: 44.3 pg/ml (29.8-78.2) vs. 20.6 (17-31.3), p = 0.032]. Amongst hypopituitary subjects, those with duration of disease greater than 1 year had higher oxytocin levels. No significant differences were observed for psychosocial measures including emotion recognition tasks.

CONCLUSIONS

Plasma oxytocin levels were found higher in patients with hypopituitarism compared to controls and highest in those with diabetes insipidus. Longer duration of hypopituitarism was also associated with higher plasma levels of oxytocin. Further study is needed to better define oxytocin deficiency and investigate response to treatment.

[Growth hormone of dried blood spot for the diagnosis of growth hormone deficiency]

INTRODUCTION

The diagnosis of growth hormone deficiency (GHD) is difficult to determine, and could be associated with severe complications, especially in the neonatal period. The stimulation test of growth hormone (GH) secretion is considered the gold standard for diagnosis, but it has methodological complications and is associated with adverse effects. Neonates present physiological increased secretion of GH, representing a diagnostic window.

OBJECTIVE

To evaluate if the dried blood spot on filter paper obtained in the neonatal period, as part of a neonatal screening for con genital hypothyroidism and phenylketonuria, allows differentiating patients with GHD from those who do not have it.

PATIENTS AND METHOD

Study of cases and controls by measuring the GH concen tration in dried blood spot on filter paper obtained in the neonatal period, comparing controls with GHD with cases with discarded deficiency. The sample was extracted from the filter paper, obtaining two 0.125 inch discs per each patient from the center of the blood spot on the paper, for a highly sen sitive ELISA assay for human GH based on the use of polyclonal antibodies against 22 kDa recom binant human GH.

RESULTS

Seven cases of GHD and ten controls were obtained. The median GH concentration of the dried blood spot in the cases is 2.0 ng/ml (Interquartile range 3.6 ng/ml) and 2.05 ng/ml (Interquartile range 2.0 ng/ml) in the controls, Mann-Whitney U test 30.5 (p = 0.68). The two cases with multiple pituitary-hormone deficiency (MPHD) present concentrations lower than 1 ng/ml.

CONCLUSION

The dried blood spot sample did not differentiate GHD patients from control cases, although MPHD cases present much lower concentrations compared to isolated growth hor mone deficiency (IGHD).

Slipped capital femoral epiphysis in an adult with congenital hypopituitarism: A case report

RATIONALE

Slipped capital femoral epiphysis (SCFE) is a common hip problem in adolescents, usually individuals between 8 and 15 years old. Because of the frequent finding of growth abnormalities in affected children, various endocrine disturbances have been reported as the cause of the disease. However, there are few case reports of older patients in previous literature. To the best of our knowledge, congenital hypopituitarism with normal growth hormone (GH) level has not been reported.

PATIENT CONCERNS

We describe a 29-year-old man who had a 3-month history of pain in the left hip with tall stature and unobvious secondary sexual characteristics. Laboratory testing showed low thyroxine, low cortisol, low follicle-stimulating hormone, low luteinizing hormone, low testosterone, but normal GH.

DIAGNOSES

Brain magnetic resonance imaging showed pituitary hypoplasia. An anteroposterior pelvis radiograph showed severe varus SCFE in the left hip, it was also confirmed with computed tomography scans.

INTERVENTIONS

The patient was treated with levothyroxine, hydrocortisone, and testosterone replacement therapy before surgery. We performed open reduction and anatomical reduction by Dunn's procedure.

OUTCOME

We have followed this patient for 6 months, the left hip mobility gradually improved. No slip in the contralateral proximal femoral physis has been observed.

LESSONS

When unobvious secondary sexual characteristics and body abnormalities were found in clinical practice, endocrine condition should be evaluated, since the contralateral side may prone to slip due to the lack of endocrine therapy.

Decreased quality of life (QoL) in hypopituitary patients: involvement of glucocorticoid replacement and radiation therapy

PURPOSE

Hypopituitary patients are assumed to have decreased QoL due to GHD. However, in placebo controlled trials, the effects of GH replacement are no different from placebo. Hydrocortisone dose > 20 mg/day and pituitary radiation are independently associated with poorer QoL. We assessed QoL in panhypopituitary GH- deficient patients never treated with GH.

METHODS

Study group was divided into: (a) surgery followed by radiation (n = 21) and (b) surgery alone (n = 32). Mean duration of GHD was 71.4 ± 7.8 months and mean daily hydrocortisone dose was 15 ± 0.7 mg. Control group had transnasal surgery for benign sinus conditions (n = 54).

RESULTS

AGHDA scores were significantly worse in the entire study group compared to controls (8.1 ± 1.0 vs. 5.1 ± 0.9, p = 0.03). In patients with history of radiation therapy AGHDA scores were significantly worse than in controls (9.1 ± 1.5, p = 0.02) and SNOT-22 (Sino-Nasal Outcome Test) scores were also significantly worse (15.8 ± 2.0 vs. 23.2 ± 3.5, p = 0.04). However, AGHDA scores in patients without history of radiation and on "physiological" dose of hydrocortisone were similar to those in controls (5.1 ± 0.9 vs. 7.3 ± 1.3, p = 0.17).

CONCLUSIONS

Replacement with hydrocortisone doses not exceeding 20 mg/day and avoidance of radiation therapy was accompanied by normal QoL in patients not replaced with GH. Thus, we suggest that the decreased QoL in hypopituitary patients may not be due to GH deficiency per se, but rather to high hydrocortisone doses and to aftereffects of cranial radiation.

Interactions between hypothalamic pituitary thyroid axis and other pituitary dysfunctions

Central hypothyroidism is defined as low circulating free thyroxine (free T4) with inappropriately low circulating thyrotropin (TSH), in context of a hypothalamic pituitary pathology. Rare cases of idiopathic central hypothyroidism caused by a functional defect may occur, and the condition is often overlooked due to difficulty in achieving the correct diagnosis, sparse symptomatology of the condition and a high risk of misinterpretion of the biochemical changes in central hypothyroidism. Central hypothyroidism is mainly seen in patients with hypothalamic-pituitary pathology due to one of many possible aetiologies, where other hormone deficiencies often co-exist, and both the presence of other deficiencies and their replacement have a strong influence on the measurement of the thyroid-related hormones and thereby interpretation of the thyroid function variables in relation to the clinical impact of thyroid hormone substitution therapy. Conversely, lack of thyroid hormone has a similar strong influence on the interpretation of other pituitary hormone axes, as well as their replacement. Undertreating patients with central hypothyroidism may have serious metabolic consequences with a potentially increased risk of cardiovascular morbidity. The present review thus aims at describing central hypothyroidism, by an overview of interactions of hypothyroidism with other pituitary hormones, diagnosing/testing for central hypothyroidism, and focusing on consequences of undertreatment. Finally, it is mentioned how to deal with new diagnostic settings with lower a priori likelihood of hypopituitarism, particularly in view of the importance of stringent diagnostic testing in order to avoid overdiagnosing central hypothyroidism.

Analysis of characteristics and outcomes by growth hormone treatment duration in adult patients in the Italian cohort of the Hypopituitary Control and Complications Study (HypoCCS)

PURPOSE

To examine differences in effects according to growth hormone (GH) treatment duration in adult GH-deficient patients.

METHODS

In the Italian cohort of the observational Hypopituitary Control and Complications Study, GH-treated adults with GH deficiency (GHD) were grouped by duration of treatment; ≤ 2 years (n = 451), > 2 to ≤ 6 years (n = 387) and > 6 years (n = 395). Between-group differences in demographics, medical history, physical characteristics, insulin-like growth factor-I standard deviation score (IGF-I SDS) and lipid profile at baseline, last study visit and changes from baseline to last study visit were assessed overall, for adult- and childhood-onset GHD and by gender using ANOVA for continuous variables and Chi-squared test for categorical variables.

RESULTS

At baseline, treatment duration groups did not differ significantly for age, gender, body mass index, GHD onset, IGF-I SDS, lipid profile, and quality of life. Mean initial GH dose did not differ significantly according to treatment duration group in any subgroup, except female patients, with highest mean dose seen in the longest duration group. In the longest duration group for patients overall, adult-onset patients and male patients, there were significant decreases in GH dose from baseline to last visit, and in total and low-density lipoprotein (LDL)-cholesterol concentrations. IGF-I SDS increased, to a greater extent, in the longest duration group for patients overall and female patients.

CONCLUSIONS

The results show that long-term GH treatment is associated with decreasing GH dose, increased IGF-I, decreased LDL-cholesterol and the presence of surrogate markers that help to give confidence in a diagnosis of GHD.

Panhypopituitarism Without GH Replacement: About Insulin Sensitivity, CRP Levels, and Metabolic Syndrome

A complete deficiency of anterior pituitary hormones from several etiologies characterizes Panhypopituitarism (PH). Despite advances in treatment, patients with PH maintain high rates of morbidity and mortality, a reason to investigate some insulin sensitivity, metabolic and inflammatory parameters that could be related to the increase of these indicators. This was a cross-sectional study comprising 41 PH patients under hormonal replacement, except for growth hormone, and 37 individuals in a control group (CG) with similar age, gender and body mass index (BMI). We assessed clinical data as age, sex, BMI, waist circumference, waist/hip ratio (WHR), history of hypertension, diabetes mellitus and dyslipidemia as well as fasting glycaemia, insulin, HOMA-IR, HbA1c, high-sensitivity CRP (hs-CRP), and lipid profile. PH patients presents lower values of glycaemia, insulin, HOMA-IR (0.88 vs 2.1) and WHR, but higher levels of hs-CRP (0.38 vs 0.16mg/dl) when compared with the CG. Although the occurrence of dyslipidemia was higher in patients with PH, the frequency of metabolic syndrome was similar between the groups. In multivariate linear regression analysis, the PH group independently predicted lower HOMA-IR and WHR values. In conclusion, this study demonstrated that patients with PH without GH replacement have lower HOMA-IR and WHR values and higher levels of hs-CRP than a CG paired by age, gender and BMI. The diagnosis of dyslipidemia was more frequent in patients with PH, but the occurrence of MS was similar to CG. Further studies are needed to confirm our findings and to better understand the metabolic characteristics of patients with PH.

Postoperative growth hormone dynamics in clinically nonfunctioning pituitary adenoma

Growth hormone deficiency (GHD) is an endocrine disorder characterized by insufficient production of growth hormone (GH). Non-functioning pituitary adenoma (NFPA) is one of common causes of GHD. Although most patients with NFPA have transsphenoidal surgery, the time-dependent changes in GH after operation have yet to be investigated. In this study, we analyzed patients with NFPAs that underwent transsphenoidal surgery. Postoperatively, GH secretion was evaluated in response to GH-releasing peptide-2 (GHRP2) infusion. We also investigated how several factors affected GH dynamics. Of 119 patients analyzed, 94 (79.0%) had peak GH levels less than 9.0 ng/mL and were diagnosed with severe GHD (sGHD) immediately after surgery. Of those patients, 27 (28.7%) recovered from sGHD within 1-2 years after surgery. Univariate analyses confirmed that sGHD recovery improved significantly in patients that were younger, had only undergone a single primary surgery, had not had anterior hormone deficiency except GH, and had cystic adenoma or normal insulin-like growth factor-1 (IGF1) standard deviation score (SD-S) levels immediately after surgery. Multivariate analyses confirmed that younger age and absence of hormone replacement therapy significantly predicted sGHD recovery within 1-2 years after surgery. Taken together, our results indicated that postoperative sGHD should be assessed by GHRP2 infusion, regardless of IGF1 SD-S levels. Furthermore, recovery from sGHD occurs more frequently at 1-2 years after surgery especially in younger patients and/or those with GH deficiency alone. These patients, therefore, should be reassessed for GHD by appropriate tests including GHRP2 test at 1-2 years after surgery.

Macimorelin as a Diagnostic Test for Adult GH Deficiency

PURPOSE

The diagnosis of adult GH deficiency (AGHD) is challenging and often requires confirmation with a GH stimulation test (GHST). The insulin tolerance test (ITT) is considered the reference standard GHST but is labor intensive, can cause severe hypoglycemia, and is contraindicated for certain patients. Macimorelin, an orally active GH secretagogue, could be used to diagnose AGHD by measuring stimulated GH levels after an oral dose.

MATERIALS AND METHODS

The present multicenter, open-label, randomized, two-way crossover trial was designed to validate the efficacy and safety of single-dose oral macimorelin for AGHD diagnosis compared with the ITT. Subjects with high (n = 38), intermediate (n = 37), and low (n = 39) likelihood for AGHD and healthy, matched controls (n = 25) were included in the efficacy analysis.

RESULTS

After the first test, 99% of macimorelin tests and 82% of ITTs were evaluable. Using GH cutoff levels of 2.8 ng/mL for macimorelin and 5.1 ng/mL for ITTs, the negative agreement was 95.38% (95% CI, 87% to 99%), the positive agreement was 74.32% (95% CI, 63% to 84%), sensitivity was 87%, and specificity was 96%. On retesting, the reproducibility was 97% for macimorelin (n = 33). In post hoc analyses, a GH cutoff of 5.1 ng/mL for both tests resulted in 94% (95% CI, 85% to 98%) negative agreement, 82% (95% CI, 72% to 90%) positive agreement, 92% sensitivity, and 96% specificity. No serious adverse events were reported for macimorelin.

CONCLUSIONS

Oral macimorelin is a simple, well-tolerated, reproducible, and safe diagnostic test for AGHD with accuracy comparable to that of the ITT. A GH cutoff of 5.1 ng/mL for the macimorelin test provides an excellent balance between sensitivity and specificity.

Screening for comorbid conditions in patients enrolled in the SODA registry: a 2-year observational analysis

PURPOSE

This 2-year analysis assessed frequency of comorbidities and comorbidity screening in the Somatuline^® (lanreotide, LAN) Depot for Acromegaly (SODA) registry.

METHODS

Patient data collected included pituitary hormone deficiencies, sleep studies, echocardiograms, gallbladder sonographies, colonoscopies, and glycated hemoglobin (HbA1c) levels. Insulin-like growth factor-1 (IGF-1) and growth hormone levels in patients with (DM) and without (non-DM) diabetes mellitus were analyzed.

RESULTS

There were 241 patients enrolled. Pituitary hormone deficiencies were reported more frequently at enrollment in male (56.9%) vs female patients (32.0%; p < 0.001). TSH deficiency was the most common endocrine deficiency (69.8%), followed by gonadotropin deficiency (62.3%). Screening tests reported at enrollment: sleep studies in 29.9% (79.2% had sleep apnea), echocardiogram in 46.1% (46.8% abnormal), gallbladder sonography in 18.7% (17.8% had gallstones), and colonoscopy in 48.1% (35.3% had polyps). Follow-up studies were reported less frequently at 1 and 2 years. HbA1c data were reported in 30.8% and 41.2% after 1 and 2 years. HbA1c levels were similar at 1 and 2 years of LAN therapy among DM and non-DM patients with available data. Fewer DM vs non-DM patients achieved IGF-1 below upper limit of normal at Month 24 (58.3% vs 80.6%; p = 0.033).

CONCLUSIONS

Fewer than half of patients in SODA had screening results reported at enrollment for sleep apnea, cardiomyopathy, and colon polyps. Gallbladder imaging was reported in a minority of patients. Lower IGF-1 control rates were observed in DM vs non-DM patients at Month 24. These data suggest a need for better monitoring of comorbidities in US acromegaly patients.

Fall in thyroid stimulating hormone (TSH) may be an early marker of ipilimumab-induced hypophysitis

PURPOSE

Hypophysitis develops in up to 19% of melanoma patients treated with ipilimumab, a cytotoxic T-lymphocyte antigen-4 antibody. Early detection may avert life-threatening hypopituitarism. We aimed to assess the incidence of ipilimumab-induced hypophysitis (IH) at a quaternary melanoma referral centre, and to determine whether cortisol or thyroid stimulating hormone (TSH) monitoring could predict IH onset.

METHODS

We performed a retrospective cohort study of ipilimumab-treated patients at a quaternary melanoma referral centre in Australia. The inclusion criteria were patients with metastatic or unresectable melanoma treated with ipilimumab monotherapy, and cortisol and TSH measurements prior to ≥ 2 infusions. The main outcomes were IH incidence and TSH and cortisol patterns in patients who did and did not develop IH.

RESULTS

Of 78 ipilimumab-treated patients, 46 met the study criteria and 9/46 (20%) developed IH at a median duration of 13.0 weeks (range 7.7-18.1) following ipilimumab initiation. All patients whose TSH fell ≥ 80% compared to baseline developed IH, and, in 5/9 patients with IH, TSH fell prior to cortisol fall and IH diagnosis. Pre-cycle-4 TSH was significantly lower in those who developed IH (0.31 vs. 1.73 mIU/L, P = 0.006). TSH fall was detected at a median time of 9.2 (range 7.7-16.4) weeks after commencing ipilimumab, and a median of 3.6 (range of - 1.4 to 9.7) weeks before IH diagnosis. There was no difference in TSH between the groups before cycles 1-3 or in cortisol before cycles 1-4.

CONCLUSIONS

TSH fall ≥ 80% may be an early marker of IH. Serial TSH measurement during ipilimumab therapy may be an inexpensive tool to expedite IH diagnosis.

Childhood-Onset Adult Growth Hormone Deficiency: Clinical, Hormonal, and Radiological Assessment in a Single Center in China

BACKGROUND

Although growth hormone deficiency (GHD) is an important issue in pediatric patients, adult GHD (AGHD) is a neglected field of endocrinology in China. The aim of this study is to characterize the clinical, hormonal, and radiological features in childhood-onset AGHD (CO AGHD) in a single center in China and to compare them with counterparts from Japan.

METHODS

The medical records of 78 Chinese patients with CO AGHD were reviewed and compared with data from the HypoCCS database study from Japan (N = 69).

RESULTS

The majority of our patients had pituitary stalk interruption, while hypothalamo-pituitary tumors were the most common cause of CO AGHD in Japan. Chinese patients had a lag of 6 years for diagnosis. The majority of both groups had multiple pituitary hormone deficiencies. Body mass index and lipid profiles were similar between the 2 patient groups. Dyslipidemia and hyperuricemia were the most common metabolic disturbances in Chinese patients.

CONCLUSIONS

Our findings confirm that there are possible regional differences in the etiology, metabolic characteristics, and hormonal status in CO AGHD patients in different countries in Asia.

Stieg M, Crispin A, Sievers C, K. Stalla G, Kopczak A. Primary Empty Sella Syndrome and the Prevalence of Hormonal Dysregulation

BACKGROUND

Empty sella is the neuroradiological or pathological finding of an apparently empty sella turcica containing no pituitary tissue. The prevalence of primary empty sella, i.e., empty sella without any discernible cause, is not precisely known; estimates range from 2% to 20%. Technical advances in neuroradiology have made empty sella an increasingly common incidental finding. It remains unclear whether, and to what extent, asymptomatic adult patients with an incidentally discovered empty sella should undergo diagnostic testing for hormonal disturbances.

METHODS

To answer this question, the authors carried out a systematic search in the PubMed and Web of Science databases for publications that appeared in the period 1995-2016 and that contained the search term "empty sella" (registration: PROSPERO 2015: CRD42015024550).

RESULTS

The search yielded 1282 hits. After the exclusion of duplicates, pediatric reports, case reports, and veterinary studies, 120 publications on primary empty sella syndrome (PES) were identified. 4 of these dealt with the prevalence of pituitary insufficiency in patients with PES as an incidental finding. Among patients with PES, the relative frequency of pituitary insufficiency in the pooled analysis was 52% (95% confidence interval [38; 65]).

CONCLUSION

The data on PES as an incidental finding are too sparse to enable any evidence-based recommendation on the potential indications for hormone testing or its nature and extent. We advise basic neuroendocrinological testing (fasting cortisol, free thyroxine [fT4], estradiol or testosterone, insulin-like growth factor 1 [IGF-1], and prolactin). There is an unexplained discrepancy between the reported high prevalence of pituitary insufficiency among persons with PES and its low prevalence in epidemiologic studies. We suspect that the former may be high because of selection bias in the publications that we reviewed, or else the latter may be erroneously low.

Effect of growth hormone replacement therapy on plasma diacron-reactive oxygen metabolites and endothelial function in Japanese patients: The GREAT clinical study

Patients with growth hormone deficiency (GHD) have an increased risk of atherosclerosis and vascular mortality. Evidence suggests that endothelial dysfunction is involved in all stages of atherogenesis. This study examined the effect of growth hormone (GH) replacement therapy on diacron-reactive oxygen metabolites (d-ROMs) and endothelial function in Japanese patients with GHD, using peripheral arterial tonometry. This was an open-label, prospective, case-control study. Nine patients with GHD who had not previously received any GH replacement therapy were enrolled. The following parameters were evaluated at baseline (before treatment), and after 24 weeks of GH replacement therapy: endothelial function using the reactive hyperemia index (RHI; EndoPAT^® system), d-ROMs, blood pressure, and fasting lipid levels. Plasma GH and insulin-like growth factor-1 (IGF-1) levels were measured at baseline and after 24 weeks of GH replacement therapy. We also enrolled eight controls with pituitary disease but no GH deficiency. Over 24 weeks of GH replacement therapy, the serum IGF-1 levels normalized with significant improvement in the RHI (from 1.65 ± 0.33 to 1.92 ± 0.26, p < 0.05) and decreased d-ROM levels (from 356.8 ± 64.1 to 303.1 ± 43.3 U.CARR, p < 0.05). There were no significant improvements in the RHI or d-ROM levels in controls. GH replacement therapy in Japanese patients with GHD may be mediated by the reduced oxidative stress and the d-ROMs associated with the treatment.

Oxidative stress in adult growth hormone deficiency: different plasma antioxidant patterns in comparison with metabolic syndrome

BACKGROUND AND AIMS

Growth hormone deficiency (GHD) is a condition associated with increased cardiovascular risk and insulin-resistance. Oxidative stress (OS) could be a mechanism underlying both these phenomena. In order to investigate plasma antioxidant defenses in such condition, we evaluated adults with GHD, compared with controls and metabolic syndrome patients (MetS), studying plasma total antioxidant capacity (TAC) and coenzyme Q10 (CoQ10, lipophilic antioxidant) levels, both in its oxidized and reduced forms, correlating this data with metabolic and hormonal pattern.

MATERIALS AND METHODS

In this case-control study, 51 GHD, 36 controls, and 35 MetS were enrolled. An evaluation of hormonal and metabolic parameters was performed. TAC was measured using the system metmyoglobin -H₂0₂ and the chromogen ABTS, whose radical form is spectroscopically revealed; latency time (LAG) in the appearance of ABTS^● is proportional to antioxidant in sample. CoQ10 was assayed by electrochemical method.

RESULTS

Despite HOMA index was higher in both GHD and MetS (2.2 ± 0.3 and 3.1 ± 0.3 vs. 1.2 ± 0.2 in controls), only in MetS we observed lower LAG levels (64.5 ± 3.1 s vs. 82.8 ± 5.8 in GHD and 80.6 ± 6.6 in controls), suggesting an increased consumption of antioxidants. LAG significantly correlated with uric acid only in MetS (r ² = 0.65, p < 0.001), suggesting a different pattern of antioxidants. CoQ10 exhibited a trend toward lower levels in GHD, although not significant.

CONCLUSIONS

Our data indicate that GHD, although sharing with MetS various metabolic features, including increased HOMA levels, showed a different pattern of plasma antioxidants, suggesting inadequate reactivity toward radical production rather than an antioxidants consumption as in MetS.

Progression from isolated growth hormone deficiency to combined pituitary hormone deficiency

Growth hormone deficiency (GHD) can present at any time of life from the neonatal period to adulthood, as a result of congenital or acquired insults. It can present as an isolated problem (IGHD) or in combination with other pituitary hormone deficiencies (CPHD). Pituitary deficits can evolve at any time from GHD diagnosis. The number, severity and timing of occurrence of additional endocrinopathies are highly variable. The risk of progression from IGHD to CPHD in children varies depending on the etiology (idiopathic vs organic). The highest risk is displayed by children with abnormalities in the Hypothalamo-Pituitary (H-P) region. Heterogeneous data have been reported on the type and timing of onset of additional pituitary hormone deficits, with TSH deficiency being most frequent and Diabetes Insipidus the least frequent additional deficit in the majority, but not all, of the studies. ACTH deficiency may gradually evolve at any time during follow-up in children or adults with childhood onset IGHD, particularly (but not only) in presence of H-P abnormalities and/or TSH deficiency. Hence there is a need in these patients for lifelong monitoring for ACTH deficiency. GH treatment unmasks central hypothyroidism mainly in patients with organic GHD, but all patients starting GH should have their thyroid function monitored closely. Main risk factors for development of CPHD include organic etiology, H-P abnormalities (in particular pituitary stalk abnormalities, empty sella and ectopic posterior pituitary), midline brain (corpus callosum) and optic nerves abnormalities, genetic defects and longer duration of follow-up. The current available evidence supports longstanding recommendations for the need, in all patients diagnosed with IGHD, of a careful and indefinite follow-up for additional pituitary hormone deficiencies.

Bone microarchitecture and estimated bone strength in men with active acromegaly

CONTEXT

Both acromegaly and adult growth hormone deficiency (GHD) are associated with increased fracture risk. Sufficient data are lacking regarding cortical bone microarchitecture and bone strength, as assessed by microfinite element analysis (µFEA).

OBJECTIVE

To elucidate both cortical and trabecular bone microarchitecture and estimated bone strength in men with active acromegaly or GHD compared to healthy controls.

DESIGN AND SUBJECTS

Cross-sectional study at a clinical research center, including 48 men (16 with acromegaly, 16 with GHD and 16 healthy controls).

OUTCOME MEASURES

Areal bone mineral density (aBMD), cortical and trabecular bone microarchitecture and estimated bone strength (µFEA) at the radius and tibia.

RESULTS

aBMD was not different between the 3 groups at any skeletal site. At the radius, patients with acromegaly had greater cortical area (P < 0.0001), cortical thickness (P = 0.0038), cortical pore volume (P < 0.0001) and cortical porosity (P = 0.0008), but lower trabecular bone density (P = 0.0010) compared to controls. At the tibia, patients with acromegaly had lower trabecular bone density (P = 0.0082), but no differences in cortical bone microstructure. Compressive strength and failure load did not significantly differ between groups. These findings persisted after excluding patients with hypogonadism. Bone microarchitecture was not deficient in patients with GHD.

CONCLUSIONS

Both cortical and trabecular microarchitecture are altered in men with acromegaly. Our data indicate that GH excess is associated with distinct effects in cortical vs trabecular bone compartments. Our observations also affirm the limitations of aBMD testing in the evaluation of patients with acromegaly.

Gender has to be taken into account in diagnosing adult growth hormone deficiency by the GHRH plus arginine test

OBJECTIVE

Data on the effect of gender on the interpretation of the GHRH plus arginine stimulation test (GHRH+ARG test) is controversial. We validated the GHRH+ARG stimulation test in control subjects and patients with organic or idiopathic pituitary disease and a suspicion of adult growth hormone deficiency (AGHD) using the Immulite 2000 XPi GH assay.

DESIGN

We studied 126 apparently healthy adults (median age 38.8years) and 34 patients with a suspicion of AGHD (median age 42.2years). Identification of AGHD with the GHRH+ARG test was investigated with commonly accepted BMI-related consensus cut-off limits for peak GH concentrations. Serum samples collected during the GHRH+ARG test were analysed for GH in 2014-2015. Serum IGF-1 concentrations were studied as a reference.

RESULTS

In 14 of 65 (22%) control males the GH peak value was below the BMI-related cut-off limits for GH sufficiency indicating a false diagnosis of AGHD. All control females had a normal GHRH+ARG response. Median peak GH response was significantly (p<0.001) higher in female (39.3μg/L) than in male controls (21μg/L). According to consensus cut-offs all but one young female patient had a deficient response compatible with a diagnosis of AGHD.

CONCLUSIONS

The GH response to stimulation by GHRH+ARG is gender-dependent, being lower in healthy males than in females. Gender should be considered when defining cut-off limits for peak GH concentrations in the GHRH+ARG test. The presently used BMI-related cut-off levels will lead to a significant misclassification of males as GH deficient.

Hypopituitarism is associated with lower oxytocin concentrations and reduced empathic ability

PURPOSE

Central diabetes insipidus is characterised by arginine vasopressin deficiency. Oxytocin is structurally related to vasopressin and is synthesised in the same hypothalamic nuclei, thus we hypothesised that patients with acquired central diabetes insipidus and anterior hypopituitarism would display an oxytocin deficiency. Moreover, psychological research has demonstrated that oxytocin influences social and emotional behaviours, particularly empathic behaviour. We therefore further hypothesised that central diabetes insipidus patients would perform worse on empathy-related tasks, compared to age-matched and gender-matched clinical control (clinical control-isolated anterior hypopituitarism) and healthy control groups.

METHOD

Fifty-six participants (age 46.54 ± 16.30 yrs; central diabetes insipidus: n = 20, 8 males; clinical control: n = 15, 6 males; healthy control: n = 20, 7 males) provided two saliva samples which were analysed for oxytocin and completed two empathy tasks.

RESULTS

Hypopituitary patients (both central diabetes insipidus and clinical control groups) had significantly lower oxytocin concentrations compared to healthy control participants. Hypopituitary patients also performed significantly worse on both the reading the mind in the eyes task and the facial expression recognition task compared to healthy control participants. Regression analyses further revealed that central diabetes insipidus patients' oxytocin concentrations significantly predicted their performance on easy items of the reading the mind in the eyes task.

CONCLUSIONS

Hypopituitarism may therefore be associated with reduced oxytocin concentrations and impaired empathic ability. While further studies are needed to replicate these findings, our data suggest that oxytocin replacement may offer a therapeutic approach to improve psychological well-being in patients with hypopituitarism.

Pulsatile GnRH Therapy May Restore Hypothalamus-Pituitary-Testis Axis Function in Patients With Congenital Combined Pituitary Hormone Deficiency: A Prospective, Self-Controlled Trial

CONTEXT

The effectiveness of pulsatile gonadotropin-releasing hormone (GnRH) therapy in patients with congenital combined pituitary hormone deficiency (CCPHD) has not been investigated because of the limited number of patients, as well as these patients' presumed pituitary hypoplasia, poor gonadotrophic cell reserve, and impaired gonadotrophic response to GnRH.

OBJECTIVE

To assess the pituitary response to pulsatile GnRH therapy in men with CCPHD.

DESIGN

Prospective, self-controlled, 3-month clinical trial.

SETTINGS

University endocrine clinic.

PATIENTS

Men with hypogonadotropic hypogonadism caused by CCPHD.

INTERVENTION

Pulsatile GnRH was administered subcutaneously for 3 months.

MAIN OUTCOME MEASURES

Primary endpoints were total serum testosterone, testicular volume, and luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels. Secondary endpoints included occurrence of spermatogenesis.

RESULTS

A total of 40 men with CCPHD completed the study. Of these, 60% (24 of 40) showed a good response to pulsatile GnRH treatment (response group). At 3 months, their LH and FSH levels increased to within the normal range and their testosterone levels increased to 8.67 ± 4.83 nmol/L. Of the patients in the response group, 33.3% (8 of 24) of them achieved spermatogenesis. The remaining 40% (16 of 40) of patients had a poor response to pulsatile GnRH treatment. Magnetic resonance imaging (MRI) did not reveal any correlation between pituitary response and pituitary height and/or integrity of the pituitary stalk.

CONCLUSIONS

This study suggests that gonadotrophs in patients with CCPHD can exist and be functional-even with MRI evidence of pituitary hypoplasia or dysplasia. Pulsatile GnRH therapy restored pituitary-testis axis function in 60% of patients with CCPHD. These results may directly guide the clinical therapeutic choice.

Rare Frequency of Mutations in Pituitary Transcription Factor Genes in Combined Pituitary Hormone or Isolated Growth Hormone Deficiencies in Korea

PURPOSE

Congenital hypopituitarism is caused by mutations in pituitary transcription factors involved in the development of the hypothalamic-pituitary axis. Mutation frequencies of genes involved in congenital hypopituitarism are extremely low and vary substantially between ethnicities. This study was undertaken to compare the clinical, endocrinological, and radiological features of patients with an isolated growth hormone deficiency (IGHD) or combined pituitary hormone deficiency (CPHD).

MATERIALS AND METHODS

This study included 27 patients with sporadic IGHD and CPHD. A mutation analysis of the POU1F1, PROP1, LHX3, LHX4, and HESX1 genes was performed using genomic DNA from peripheral blood leukocytes.

RESULTS

IGHD and CPHD were observed in 4 and 23 patients, respectively. Mean age at diagnosis was 8.28±7.25 years for IGHD and 13.48±10.46 years for CPHD (p=0.37). Serum insulin-like growth factor-1 and peak growth hormone (GH) levels following GH stimulation tests were significantly lower in patients with CPHD than in those with IGHD (p<0.05). Sellar MRI findings revealed structural abnormalities in 3 patients with IGHD (75%) and 21 patients with CPHD (91.3%) (p=0.62). A mutation analysis identified homozygous p.R109Q mutations in HESX1 in a patient with CPHD. Patients with CPHD had more severe GHD than those with IGHD.

CONCLUSION

The frequency of defects in the genes encoding pituitary transcription factors was extremely low in Korean patients with congenital hypopituitarism. Environmental factors and the impact of other causative genes may contribute to this clinical phenotype.

The effect of growth hormone replacement on the thyroid axis in patients with hypopituitarism: in vivo and ex vivo studies

OBJECTIVE

Alterations in the hypothalamic-pituitary-thyroid axis have been reported following growth hormone (GH) replacement. The aim was to examine the relationship between changes in serum concentration of thyroid hormones and deiodinase activity in subcutaneous adipose tissue, before and after GH replacement.

DESIGN

A prospective, observational study of patients receiving GH replacement as part of routine clinical care.

PATIENTS

Twenty adult hypopituitary men.

MEASUREMENTS

Serum TSH, thyroid hormones - free and total thyroxine (T4) and triiodothyronine (T3) and reverse T3, thyroglobulin and thyroid-binding globulin (TBG) levels were measured before and after GH substitution. Changes in serum hormone levels were compared to the activity of deiodinase isoenzymes (DIO1, DIO2 and DIO3) in subcutaneous adipose tissue.

RESULTS

The mean daily dose of growth hormone (GH) was 0·34 ± 0·11 mg (range 0·15-0·5 mg). Following GH replacement, mean free T4 levels declined (-1·09 ± 1·99 pmol/l, P = 0·02). Reverse T3 levels also fell (-3·44 ± 1·42 ng/dl, P = 0·03) and free T3 levels increased significantly (+0·34 ± 0·15 pmol/l, P = 0·03). In subcutaneous fat, DIO2 enzyme activity declined; DIO1 and DIO3 activities remained unchanged following GH substitution. Serum TSH, thyroglobulin and TBG levels were unaltered by GH therapy.

CONCLUSIONS

In vitro analysis of subcutaneous adipose tissue from hypopituitary human subjects demonstrates that GH replacement is associated with significant changes in deiodinase isoenzyme activity. However, the observed variation in enzyme activity does not explain the changes in the circulating concentration of thyroid hormones induced by GH replacement. It is possible that deiodinase isoenzymes are differentially regulated by GH in other tissues including liver and muscle.

Critical review of IgG4-related hypophysitis

PURPOSE

IgG4-related hypophysitis is a rare disease, with only 34 cases published in English (2015). Available short reviews may not present complete details of IgG4-related hypophysitis. We aimed to survey case reports of IgG4-related hypophysitis, including abstracts of scientific meetings, in English and Japanese.

METHODS

We searched for information about IgG4-related hypophysitis in PubMed and Igakuchuozasshi (Japan Medical Abstracts Society). Among 104 case reports found, we reviewed 84 fulfilling Leporati's diagnostic criteria.

RESULTS

The mean ±  SD age of onset was 64.2  ±  13.9, 67.5  ±  9.8, and 56.4  ±  18.6 years for all subjects, men, and women, respectively. Men:women was 2.4:1. On magnetic resonance imaging, pituitary, stalk, and pituitary-stalk mass were observed at frequencies of 14.3, 21.4, and 64.3%, respectively. Manifestations were anterior hypopituitarism in 26.2% (22 cases), central diabetes insipidus in 17.9% (15 cases), and panhypopituitarism in 52.4% (44 cases). The median level of serum IgG4 was 264.5 mg/dL for all subjects, 405 mg/dL for men, and 226 mg/dL for women. The mean number of IgG4-related systemic diseases was 2.7  ±  1.5 in all subjects, 3.0  ±  1.5 in men, and 1.8  ±  1.1 in women. Among the IgG4-related diseases, retroperitoneal fibrosis was the most frequent (26.2%), followed by salivary gland diseases (25%). Glucocorticoid therapy was generally effective, except for two cases that received replacement doses. There were significant differences between sexes in terms of age, serum IgG4 levels, and number of IgG4-related diseases.

CONCLUSION

IgG4-related hypophysitis may have different clinical characteristics between genders. This survey may lack some information because the Japanese abstracts did not contain certain details.

One-year GH replacement therapy reduces early cardiac target organ damage (TOD) in adult GHD patients

Hypopituitarism reduces life expectancy and increases the risk of cardiovascular and cerebrovascular diseases, as well as death. Abnormalities in the cardiovascular system may be independently related to GH deficiency (GHD). The aim of this study was to prospectively investigate coronary flow reserve and diastolic function in GHD adult patients at diagnosis and after 1 year of GH replacement therapy. As control group, an age- and sex-matched population was chosen. All patients and controls were non-smokers, non-diabetic, and normotensive, with no history of vascular disease. 14 patients with adult-onset GHD and 17 controls represent the two study groups. Anthropometric data, blood pressure, lipid profile, glycosylated hemoglobin (HbA1c) and IGF-I plasma levels, coronary flow reserve (CFR), and LV diastolic function (evaluated by E/A) were collected in all subjects before and after 12 months of GH replacement therapy. Compared with controls, systolic and diastolic blood pressure and LDL cholesterol levels were significantly higher at baseline and return, comparable to controls after 1 year of GH replacement (GHRT). GHD patients showed a blunted CFR at baseline (P < 0.001) and a significant improvement after GHRT, returning to values comparable with those recorded in the control group. In addition, after therapy a significant (P < 0.001) improvement in E/A was recorded. One year of GH therapy improves CFR and E/A in the patient population analyzed, thereby encouraging the early start of GHRT.