Loss of vagal integrity disrupts immune components of the microbiota-gut-brain axis and inhibits the effect of Lactobacillus rhamnosus on behavior and the corticosterone stress response.

The vagus nerve is one of the major signalling components between the gut microbiota and brain. However, the exact relationship between gut-brain signaling along the vagus and the effects of gut microbes on brain function and behaviour is unclear. In particular, the relationship between the vagus nerve and immune signaling, that also appears to play a critical role in microbiota-gut-brain communication, has not been delineated. The aim of the present study was to determine the effect of subdiaphragmatic vagotomy on peripheral and central immune changes associated with the anxiolytic actions of L.rhamnosus. Male mice underwent vagotomy or sham surgery, followed by administration of L.rhamnosus for 14 days. L.rhamnosus administration following sham surgery resulted in reduced anxiety-like behaviour, and an attenuation of the hypothalamic-pituitary-adrenal axis (HPA axis), as indicated by reduced plasma corticosterone after acute restraint stress. These effects were associated with an increase in splenic T regulatory cells and a decrease in activated microglia in the hippocampus. The anxiolytic effects, HPA modulation and increase in T regulatory cells were prevented by vagotomy, whereas vagotomy alone led to a significant increase in activated microglia in the hippocampus that was not altered with L.rhamnosus treatment. Thus, both microbe induced and constitutive vagal signaling influences critical immune components of the microbiota-gut-brain axis. These findings suggest that, rather than acting as a direct neural link to the central nervous system, the role of the vagus nerve in gut-microbe to brain signalling is as an integral component of a bi-directional neuroimmunoendocrine pathway.

Partial Reconstitution of the Hypothalamo-Pituitary Axes After Pituitary Stalk Sectioning and Specific Magnetic Resonance Imaging Findings.

BACKGROUND: Pituitary stalk sectioning is only essential in cases of craniopharyngioma originating from the stalk or metastatic tumor to the stalk. Some patients can discontinue postoperative antidiuretic hormone (ADH) supplementation with special conditions. METHODS: Sixty-three patients with craniopharyngiomas who were treated by surgery with pituitary stalk sectioning were included in this study. Great care was taken to preserve the fine arteries running along the lateral walls of the third ventricle. Removal rates, change of endocrinologic status, and magnetic resonance imaging (MRI) findings were investigated. RESULTS: Total removal was achieved in 52 of 54 patients in initial surgery (96.3%), and in 5 of 9 patients in retreatment (55.6%). ADH supplementation was required in all patients from the day of surgery, but was discontinued in 29 of 54 patients among the initial surgery group (53.7%) and in 2 of 9 patients among the retreatment group (22.2%). Preservation of thyroid hormone secretion was observed in 24 of 31 patients who could discontinue ADH (77.4%), but only in 12 of 32 patients who could not discontinue ADH (37.5%). Recovery from diabetes insipidus (DI) was significantly associated with preservation of thyroid function (P < 0.01). Postoperative MRI showed that part of the hypothalamus was enhanced in patients with recovery from DI. CONCLUSIONS: Total removal was achieved in 91% of all cases. Half of the patients could discontinue ADH supplementation, which was associated with preservation of thyroid function. The findings of hypothalamic enhancement on postoperative MRI may be associated with recovery from DI.

Clinical Consultation Guide on Imaging in Male Infertility and Sexual dysfunction.

Imaging can benefit clinicians in evaluating men with infertility or sexual dysfunction by giving an overview of a patient's overall clinical condition before undertaking an invasive procedure. An understanding of the limitations and advantages of image modalities used in clinical practice will ensure that clinicians can optimize patient care with imaging when necessary. PATIENT SUMMARY: The objective of this article was to review the current literature on imaging modalities used for the diagnosis and management of male infertility and sexual dysfunction. An understanding of the advantages and limitations of these imaging modalities will ensure that clinicians can optimize patient care with imaging when necessary.

Prediction of pituitary stalk position in pituitary adenomas by visualization of the hypothalamo-hypophyseal tract using diffusion tensor imaging tractography.

The preservation of pituitary stalk during surgery is very important for neurosurgeons. Sometimes, it is hard to identify the pituitary stalk in the operation. The hypothalamo-hypophyseal tract (HHT) projects through the pituitary stalk to the posterior pituitary gland. If the HHT can be identified, the position of pituitary stalk will be visualized. The diffusion tensor imaging (DTI) fiber tracking technique has been widely used for the quantitative assessment of the white matter integrity and thus may be suitable for the evaluation of the HHT.DTI was used to track the HHT in 11 patients with pituitary adenoma, and the location of the tract was compared with the pituitary stalk of postoperative image in those patients.The fiber tracking and 3D visualization of the HHT were successfully carried out in all 11 patients. Comparison between the tract and pituitary stalk of postoperative magnetic resonance imaging (MRI) was carried out in 9 patients. The results revealed that the position of tract was consistent with the pituitary stalk of postoperative MRI image in 8 patients (88.9%). The properties of tract showed that the median number of tract was 5.18 ±â€Š7.00, the median fractional anisotropy (FA) was 0.14 ±â€Š0.04, and the median length was 28.81 ±â€Š7.94 mm.HHT can be tracked and visualized with the DTI-FT technique. It will be helpful to identify the location of pituitary stalk preoperatively.

Predicting pituitary stalk position by in vivo visualization of the hypothalamo-hypophyseal tract in craniopharyngioma using diffusion tensor imaging tractography.

The pituitary stalk (PS) is crucial to endocrine function and water-electrolyte equilibrium. Preservation of the PS during craniopharyngioma (CP) surgery is critical; however, in a pathological state, it is difficult to identify. The hypothalamo-hypophyseal tract (HHT) connects the hypothalamus and the posterior pituitary gland and projects through the PS. Thus, visualization of the HHT can help locate the PS. Preoperative visualization of the neural fasciculus has been widely achieved using diffusion tensor imaging (DTI) tractography. Therefore, this study evaluated the use of DTI tractography to identify and characterize the human HHT. We used DTI tractography to track the HHT in 10 patients with CP and compared the location of the tract with the intraoperative view of the PS in these patients. We successfully tracked the HHT in nine patients, indicating that delineating and quantifying the tracked HHT using this method is feasible. In addition, we found that the tract was consistent with the intraoperative view of the PS in seven out of eight patients (87.50%). Finally, we found that the mean number of tracts was 7.11 ± 12.28, the mean fractional anisotropy (FA) was 0.11 ± 0.04, and the mean tract length was 24.22 ± 9.39 mm. Taken together, our results demonstrate that the HHT can be visualized and characterized with DTI even in a clinical application, which may aid in preoperative identification of the PS. Characterization of the tracked HHT with this technique could also be used to advance our understanding of the HHT.

The Utility of Routine Ultrasound in the Diagnosis and Management of Adolescents with Abnormal Uterine Bleeding.

STUDY OBJECTIVE: Despite the fact that most cases of abnormal uterine bleeding (AUB) in adolescence are due to an immature hypothalamic-pituitary-ovarian (HPO) axis, the current approach to investigating adolescents who present with AUB often includes pelvic ultrasound to exclude rare structural causes. The aim of this study was to determine whether an ultrasound ordered for the investigation of AUB in adolescents detects any significant anatomic pathology or alters diagnosis and management. DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS: A retrospective chart review of 230 patients younger than 18 years of age who presented with AUB to the gynecology clinic at the Hospital for Sick Children in Toronto, Canada between January 2010 and December 2012 was completed. MAIN OUTCOME MEASURES: Findings on pelvic ultrasound and any further imaging as well as management choices for these patients were examined. RESULTS: Of all patients, 67.8% (156/230) had ultrasound done as part of their AUB workup. The most common diagnosis for the patients who received ultrasound examinations and the patients who did not was AUB due to an immature HPO axis. Of the patients who received an ultrasound examination, 72.4% (113/156) had normal findings; incidental findings were identified in 17.9% (28/156) and polycystic ovary syndrome morphology in 6.4% (10/156). Structural causes of AUB were found in only 2 (1.3%) of the adolescents imaged. No patient had a change in her AUB management plan because of ultrasound findings. CONCLUSION: Our results strongly suggest that pelvic ultrasound examination is not required in the initial investigation of AUB in the adolescent population because it did not alter treatment in any of our patients.

Severe hypothalamopituitary dysfunction accompanied by influenza-associated encephalopathy: report of two pediatric cases.

Severe influenza infection may lead to neurological damage, such as encephalopathy. This may, in turn, cause acquired hypothalamopituitary dysfunction, which can result in severe morbidity and even death. We herein report two pediatric patients who developed influenza-associated hypopituitarism and were subsequently diagnosed with encephalopathy. They were diagnosed with acute necrotizing encephalopathy and postresuscitation encephalopathy, respectively. Both showed evidence of endocrine dysfunction, and hormone replacement therapy of adrenal, thyroid, and antidiuretic hormones are resulting in continued cardiac activity and resulted in prolonged survival. Screening for endocrine function is important in patients with severe central nervous system dysfunction.

Endocrine manifestations in Langerhans cell histiocytosis.

Langerhans cell histiocytosis is a rare, multisystem disease that shows a particular predilection for hypothalamo-pituitary axis involvement. Diabetes insipidus is the most frequent permanent consequence of Langerhans cell histiocytosis, developing in around a quarter of patients. Although the exact prevalence of anterior pituitary hormone deficiencies is not known, it is probably high and is almost always associated with diabetes insipidus. Established pituitary hormone deficiencies are mostly permanent and require prompt diagnosis and treatment, whereas continuous follow-up is needed to detect deficiencies that might evolve later during the course of the disease. Involvement of endocrine tissues other than the pituitary has also been described but is relatively rare. Further studies are needed to evaluate the effect that endocrine deficiencies exert on the overall prognosis of patients with Langerhans cell histiocytosis.

[Hyperprolactinemia: causes, diagnosis, and treatment]. / Hiperprolaktynemia: przyczyny, diagnostyka, leczenie.

The basic data on hyperprolactinemia (i.e. an excess of PRL above a reference laboratory's upper limits), the most common endocrine disorder of the hypothalamic-pituitary axis are given in this review. The following issues are discussed: regulation of prolactin (Prl) secretion, definition of hyperprolactinemia, its etiology and pathogenesis as well as its symptoms, diagnosis, and treatment (including medical and surgical therapy). It should be stressed that finding of elevated PRL serum concentrations constitute the beginning of diagnostic procedure and, after exclusion of physiologic, pharmacologic, and other organic causes of increased PRL levels, should be followed by detailed diagnosis including MRI. In patients in whom hyperprolactinemia has been confirmed the treatment with dopamine agonists (with prevalence of cabergoline, followed by quinagoline) is currently considered first-choice therapy. Surgery should be performed only in the patients resistant or intolerant to these agents, or in patients who refuse long-term therapy.

[Neuroradiological investigation in patients with idiopathic growth hormone deficiency]. / Investigação neurorradiológica de pacientes com deficiência idiopática de hormônio do crescimento.

OBJECTIVE: The aim of this study was to analyze the type and frequency of cranial computed tomography and magnetic resonance imaging anomalies in patients with idiopathic growth hormone deficiency, and also to investigate the possible relationship between neuroradiological images and the presence of isolated growth hormone or multiple pituitary hormone deficiency. METHODS: Magnetic resonance and computed tomography images were obtained for 37 patients with idiopathic growth hormone deficiency. The patients were divided into two groups: patients with isolated growth hormone (group A) and patients with multiple pituitary hormone deficiencies (group B). RESULTS: Computed tomography was normal in 25 (68%), and abnormal in 12 (32%) patients. We observed empty sella in 50%, partially empty sella in 17% and anterior pituitary hypoplasia in 33% patients. MRI studies revealed normal findings in the hypothalamus-pituitary area in 17 (46%) and abnormal in 20 (54%) patients. We did not observed differences in the frequency of computed tomography alterations when groups A and B were compared (p = 0.55). With magnetic resonance imaging we observed, empty sella in 10%, partially empty sella in 15% and anterior pituitary hypoplasia in 75% patients. Among those patients whose magnetic resonance images were altered, the posterior lobe of the pituitary gland was identified in an abnormal position in 70%, and the hypophyseal stalk was thin or interrupted in 60%. The patients from group B presented a higher frequency of magnetic resonance imaging anomalies (90%) when compared to group A (10%), p = 0.03. There was disagreement between the two methods in 43% of cases, but we didn't observe a difference in the frequency of alterations when computed tomography was compared with magnetic resonance imaging (p = 0.06). CONCLUSIONS: The most frequent defects observed using magnetic resonance imaging are anterior pituitary hypoplasia and ectopic posterior pituitary lobe. The association of glandular hypoplasia with other magnetic resonance imaging abnormalities can suggest the presence of multiple anterior pituitary deficiencies.

[Assessment of endocrine disorders of the hypothalamic-pituitary axis by nuclear medicine techniques]. / Nuklearmedizinische Verfahren zur Abklärung endokrinologischer Erkrankungen der Hypothalamus-Hypophysen-Achse.

The following article reviews nuclear medicine techniques which can be used for assessment of endocrine disorders of the hypothalamic-pituitary axis. For planar and SPECT imaging somatostatin-receptor- and dopamine-D2-receptor-scintigraphy are the most widely distributed techniques. These nuclear medicine techniques may be indicated in selected cases to answer differential diagnostic problems. They can be helpful to search for presence and localization of receptor positive tissue. Furthermore they can detect metastasis in the rare cases of a pituitary carcinoma. Scintigraphy with Gallium-67 is suitable for further diagnostic evaluation in suspected hypophysitis. Other SPECT radiopharmaca do not have relevant clinical significance. F-18-FDG as PET radiopharmacon is not ideal because obvious pituitary adenomas could not be visualized. Other PET radiopharmaca including C-11-methionine, C-11-tyrosine, F-18-fluoroethylspiperone, C-11-methylspiperone, and C-11-raclopride are available in specialized centers only. Overall indications for nuclear medicine in studies for the assessment of endocrine disorders of the hypothalamic-pituitary-axis are rare. Original studies often report only about a small number of patients. According to the authors' opinion the relevance of nuclear medicine in studies of clinically important endocrinologic fields, e.g. localization of small ACTH-producing pituitary adenomas, tumor localization in ectopic ACTH syndrome, localization of recurrent pituitary tissue, assessment of small incidentalomas, can not be definitely given yet.

Long-term follow-up evaluation of magnetic resonance imaging in the prognosis of permanent GH deficiency.

OBJECTIVE: In patients with GH deficiency (GHD), magnetic resonance imaging (MRI) has revealed morphological abnormalities such as pituitary hypoplasia, pituitary stalk agenesis (PSA) and ectopia of the posterior pituitary (PPE). The MRI anomalies have been more frequently reported in patients with multiple pituitary hormone deficiency (MPHD) than in subjects with isolated GH deficiency (IGHD). The aim of this work was to define which MRI anatomical abnormalities of the hypothalamo-pituitary area can be considered as a prognostic marker of permanent GHD. DESIGN: To investigate the relationship between the neuroradiological images and endocrine findings, we clinically re-evaluated 93 out of the 121 GHD patients with IGHD and MPHD previously studied. RESULTS: No additional hormone deficiencies were observed in 55 out of 60 patients initially classified as having IGHD with a normal (15 cases) or reduced (40 cases) pituitary gland size, without other MRI abnormalities. The remaining five children, who had initially shown an apparently IGHD in spite of PSA and PPE, developed a MPHD over time. In 33 MPHD patients with (25 cases) or without (8 cases) MRI abnormalities, the associated hormone deficiencies were confirmed during follow-up. CONCLUSIONS: The IGHD patients showing PSA and PPE inevitably develop additional hormone deficiencies, while IGHD subjects having no MRI abnormalities maintain IGHD. Moreover, the anatomical abnormalities of the hypothalamo-pituitary area can be considered as a prognostic marker of permanent GHD.

Ictal laughter associated with paroxysmal hypothalamopituitary dysfunction.

PURPOSE: Seizures with ictal laughter (also termed gelastic seizures) have been associated with hypothalamic hamartomas and precocious puberty. It is not known, however, where in the brain such seizures originate. We describe a child with gelastic seizures and a hypothalamic lesion (probably a hamartoma) in whom two dysfunctional phenomena were observed. RESULTS: First, there was a hyperperfusion in the hypothalamopituitary areas shown by ictal [99m]Tc hexamethyl-propyleneamine oxime (HM-PAO) single photon-emission computed tomography (SPECT). Second, there was an ictal pulse of gonadotropins, 17 beta-estradiol, and growth hormone well above the normal limits in one of the seizures. CONCLUSION: These findings suggest that gelastic seizures associated with hypothalamic hamartomas are generated in the hypothalamus or in its neighboring regions and that these seizures may cause paroxysmal dysfunction of the hypothalamopituitary axis.

Empty sella turcica in intracranial sarcoidosis. Pituitary insufficiency, primary polydipsia, and changing neuroradiologic findings.

A 37-year-old man with visual loss was found to have hypopituitarism and primary polydipsia associated with sarcoidosis. Neuroradiologic studies demonstrated a dramatic evolution of CNS lesions, including a left thalamic infarct, an enhancing suprasellar mass, and ultimately an empty sella turcica. The patient has been clinically stable in spite of these changes. This case is likely to be the first reported of CNS sarcoidosis with an empty sella turcica documented by computed tomography.

Current approaches to hypothalamic-pituitary radiology.

Currently computed tomography (CT) is the primary imaging modality for pituitary and hypothalamic lesions, although it is probable that NMR will supersede it. The range of size of the normal pituitary is considerable, with relatively larger glands occurring in adolescence and females of childbearing age. Asymptomatic microadenomas and cysts are not infrequent so that small low-density lesions in a gland on the borderline of enlargement can only be assessed in relation to clinical presentation. Patients presenting with clinical or biochemical evidence of abnormal pituitary hormone secretion or with an enlarged sella but without evidence of any neurological abnormality are likely to have either a small pituitary tumour or an empty sella and are investigated by thin section high resolution CT to produce coronal and sagittal images. Visual defects, paralysis of ocular muscles or hypothalamic disturbances, in the absence of clinical evidence of hypersecretion of pituitary hormones, may be due to a variety of pathologies. These cases are elucidated by plain plus contrast-enhanced CT, supplemented as necessary by angiography and computed cysternography after injection of non-ionic contrast media. Hypothalamic disturbances may occasionally complicate cerebral malformations which are also elucidated by cranial CT.

Computed tomography in diabetes insipidus.

Thirteen patients aged 1 to 59 years hospitalized for diabetes insipidus (DI) were investigated by computed tomography (CT). Apart from one craniopharyngioma, CT revealed in 8 out of 12 cases several modifications in the hypothalamic-pituitary region. In this group, CT demonstrated a small, round, isodense mass in the chiasmatic cistern that enhanced after contrast medium injection. Coronal and sagittal reconstructions helped pinpoint the lesion in the infundibulum and pituitary stalk, and, in one case, in the supraoptic nuclei. These findings, and the noninvasiveness of CT, make this technique one of the most accurate means of radiological investigation of DI and also of determining the efficacy of therapy.