Pituitary T1 signal intensity at magnetic resonance imaging is reduced in patients with obesity: results from the CHIASM study.

BACKGROUND: Despite obesity being well known to be associated with several pituitary hormone imbalances, pituitary appearance in magnetic resonance imaging (MRI) in patients with obesity is understudied. OBJECTIVE: To evaluate the pituitary volume and signal intensity at MRI in patients with obesity. METHODS: This is a prospective study performed in an endocrine Italian referral center (ClinicalTrial.gov Identifier: NCT03458533). Sixty-nine patients with obesity (BMI > 30 kg/m2) and twenty-five subjects without obesity were enrolled. Thirty-three patients with obesity were re-evaluated after 3 years of diet and lifestyle changes, of whom 17 (51.5%) achieved a > 5% loss of their initial body weight, whereas the remaining 16 (48.5%) had maintained or gained weight. Evaluations included metabolic and hormone assessments, DEXA scan, and pituitary MRI. Pituitary signal intensity was quantified by measuring the pixel density using ImageJ software. RESULTS: At baseline, no difference in pituitary volume was observed between the obese and non-obese cohorts. At the 3-year follow-up, pituitary volume was significantly reduced (p = 0.011) only in participants with stable-increased body weight. Furthermore, a significant difference was noted in the mean pituitary intensity of T1-weighted plain and contrast-enhanced sequences between the obese and non-obese cohorts at baseline (p = 0.006; p = 0.002), and a significant decrease in signal intensity was observed in the subgroup of participants who had not lost weight (p = 0.012; p = 0.017). Insulin-like growth factor-1 levels, following correction for BMI, were correlated with pituitary volume (p = 0.001) and intensity (p = 0.049), whereas morning cortisol levels were correlated with pituitary intensity (p = 0.007). The T1-weighted pituitary intensity was negatively correlated with truncal fat (p = 0.006) and fibrinogen (p = 0.018). CONCLUSIONS: The CHIASM study describes a quantitative reduction in pituitary intensity in T1-weighted sequences in patients with obesity. These alterations could be explained by changes in the pituitary stromal tissue, correlated with low-grade inflammation.

Pituitary adenoma consistency affects postoperative hormone function: a retrospective study.

BACKGROUND: Tumor consistency recently emerged as a key factor in surgical planning for pituitary adenomas, but its impact on postoperative endocrine function is still unclear. Our study aimed to evaluate the impact of tumor consistency on the development of postoperative pituitary deficiencies. METHODS: Single-center, retrospective analysis of consecutive pituitary surgeries performed between January 2017 and January 2021 at Policlinico Umberto I in Rome. All patients underwent radiological and biochemical evaluations at baseline, and hormone assessments 3 and 6 months after pituitary surgery. Postoperative MRI studies were used to determine resection rates following surgery. Data on tumor consistency, macroscopic appearance, neurosurgical approach, and intraoperative complications were collected. RESULTS: Fifty patients [24 women, mean age 57 ± 13 years, median tumor volume 4800 mm3 [95% CI 620-8828], were included. Greater tumor volume (χ2 = 14.621, p = 0.006) and male sex (χ2 = 12.178, p < 0.001) were associated with worse preoperative endocrine function. All patients underwent transsphenoidal adenomectomy. Fibrous consistency was observed in 10% of patients and was associated with a Ki-67 greater than 3% (χ2 = 8.154, p = 0.04), greater risk of developing postoperative hormone deficiencies (χ2 = 4.485, p = 0.05, OR = 8.571; 95% CI: 0.876-83.908), and lower resection rates (χ2 = 8.148, p = 0.004; OR 1.385, 95% CI; 1.040-1.844). Similarly, worse resection rates were observed in tumors with suprasellar extension (χ2 = 5.048, p = 0.02; OR = 6.000, 95% CI; 1.129-31.880) and CSI (χ2 = 4.000, p = 0.04; OR = 3.857, 95% CI; 0.997-14.916). CONCLUSIONS: Tumor consistency might provide useful information about postoperative pituitary function, likely due to its impact on surgical procedures. Further prospective studies with larger cohorts are needed to confirm our preliminary findings.

Ketogenic diet: a tool for the management of neuroendocrine neoplasms?

Neuroendocrine neoplasms (NENs) are a heterogeneous group of neoplasms, whose incidence has rapidly increased in the last years. Nutrition plays an important role in their management; indeed, malnutrition negatively impacts on rates of complications, hospitalization, hospital stay, costs and mortality. Furthermore, it has been reported that a poor nutritional status could influence the outcome of patients with pancreatic NENs. Moreover, obesity, predisposing to insulin resistance and compensatory hyperinsulinemia, could stimulate the growth of these neoplasms. Ketogenic diet (KD), a high-fat, low-carbohydrate diet with adequate amounts of protein, has been reported to be a promising approach for the management of several types of cancer, mostly gynecological and neurological ones. Indeed, it appears to sensitize most cancers to standard treatment by exploiting the reprogramed metabolism of cancer cells and thus resulting in a promising candidate as an adjuvant cancer therapy. Thus, the aim of this review is to provide an overview on the importance of nutrition in cancer management and in particular in NENs' setting. Furthermore, we reported the current evidence on the efficacy of KD in the management of cancer and based on molecular mechanisms; we also hypothesize the potential use of this nutritional pattern in the management of NENs.

Beyond Bone: Infectious Diseases and Immunity in Parathyroid Disorders.

Parathyroid disorders are characterized by alterations in calcium and phosphate homeostasis due to inappropriately high or low levels of parathyroid hormone (PTH). Despite PTH receptor type 1 has been described in almost all immune lineages and calcium signalling has been confirmed as a crucial mediator for immune response, in vitro studies on the physiological interactions between PTH and immunity are conflicting and not representative of the clinical scenarios seen in patients with parathyroid disorders. Infectious diseases are among the main causes of increased morbidity and mortality in patients with secondary hyperparathyroidism and chronic kidney disease. More, immune alterations have been described in primary hyperparathyroidism. Recent studies have unveiled an increased risk of infections also in hypoparathyroidism, suggesting that not only calcium, but also physiological levels of PTH may be necessary for a proper immune response. Finally, calcium/phosphate imbalance could affect negatively the prognosis of infectious diseases. Our review aimed to collect available data on infectious disease prevalence in patients with parathyroid disorders and new evidence on the role of PTH and calcium in determining the increased risk of infections observed in these patients.

From microbiota toward gastro-enteropancreatic neuroendocrine neoplasms: Are we on the highway to hell?

Gut microbiota is represented by different microorganisms that colonize the intestinal tract, mostly the large intestine, such as bacteria, fungi, archaea and viruses. The gut microbial balance has a key role in several functions. It modulates the host's metabolism, maintains the gut barrier integrity, participates in the xenobiotics and drug metabolism, and acts as protection against gastro-intestinal pathogens through the host's immune system modulation. The impaired gut microbiota, called dysbiosis, may be the result of an imbalance in this equilibrium and is linked with different diseases, including cancer. While most of the studies have focused on the association between microbiota and gastrointestinal adenocarcinomas, very little is known about gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs). In this review, we provide an overview concerning the complex interplay between gut microbiota and GEP NENs, focusing on the potential role in tumorigenesis and progression in these tumors.

Cortisol Circadian Rhythm and Insulin Resistance in Muscle: Effect of Dosing and Timing of Hydrocortisone Exposure on Insulin Sensitivity in Synchronized Muscle Cells.

INTRODUCTION/AIM: Circadian clock disruption is emerging as a risk factor for metabolic disorders, and particularly, alterations in clock genes circadian expression have been shown to influence insulin sensitivity. Recently, the reciprocal interplay between the circadian clock machinery and hypothal-amus-pituitary-adrenal axis has been largely demonstrated: the circadian clock may control the physiological circadian endogenous glucocorticoid (GC) secretion and action; GCs, in turn, are potent regulators of the circadian clock and their inappropriate replacement has been associated with metabolic impairment. The aim of the current study was to investigate in vitro the interaction between the timing-of-the-day exposure to different hydrocortisone (HC) concentrations and muscle insulin sensitivity. METHODS: Serum-shock synchronized mouse skeletal muscle C2C12 cells were exposed to different HC concentrations resembling the circulating daily physiological cortisol profile (standard cortisol profile) and the circulating daily cortisol profile that reached in adrenal insufficient (AI) patients treated with once-daily modified-release HC (flat cortisol profile) and treated with thrice-daily conventional immediate-release HC (steep cortisol profile). The 24 h spontaneous oscillation of the clock genes in synchronized C2C12 cells was used to align the timing for in vitro HC exposure (Bmal1 acrophase, midphase, and bathyphase) with the reference times of cortisol peaks in AI patients treated with IR-HC (8 a.m., 1 p.m., and 6 p.m.). A panel of 84 insulin sensitivity-related genes and intracellular insulin signaling proteins were analyzed by RT-qPCR and Western blot, respectively. RESULTS: The steep profile, characterized by a higher HC exposure during Bmal1bathyphase, produced significant downregulation in 21 insulin sensitivity-related genes including Insr, Irs1, Irs2, Pi3kca, and Adipor2, compared to the flat and standard profile. Reduced intracellular IRS1 Tyr608, AKT Ser473, AMPK Thr172, and ACC Ser79 phosphorylations were also observed. CONCLUSIONS: The current study demonstrated that late-in-the-day cortisol exposure modulates insulin sensitivity-related gene expression and intracellular insulin signaling in skeletal muscle cells.

Abnormal linear growth in paediatric adrenal diseases: Pathogenesis, prevalence and management.

Abnormal adrenal function can interfere with linear growth, potentially causing either acceleration or impairment of growth in paediatric patients. These abnormalities can be caused by direct effects of adrenal hormones, particularly glucocorticoids and sex steroids, or be mediated by indirect mechanisms such as the disturbance of the growth hormone-insulin-like growth factor-1 axis and aromatization of androgens to oestrogens. The early diagnosis and optimal treatment of adrenal disorders can prevent or minimize growth disturbance and facilitate improved height gain. Mechanisms of growth disturbance in the following abnormal states will be discussed; hypercortisolaemia, hyperandrogenaemia and obesity. Prevalence and features of growth disturbance will be discussed in ACTH-dependent and ACTH-independent Cushing's syndrome, adrenocortical tumours, premature adrenarche, congenital adrenal hyperplasia and adrenal insufficiency disorders. Recommendations for management have been included.

Thyroid disorders in programmed death 1 inhibitor-treated patients: Is previous therapy with tyrosine kinase inhibitors a predisposing factor?

BACKGROUND: Programmed death 1 (PD-1) inhibitors are frequently associated with thyroid-related adverse events (TAEs), but many aspects remain unclear. This study aims to evaluate the incidence and characteristics of such events and to find any predictive factor for its development. METHODS: We retrospectively analysed data from patients with advanced solid tumours (non-small-cell lung carcinoma, renal cell carcinoma, metastatic melanoma) treated with PD-1 inhibitors (nivolumab, pembrolizumab) in Oncology Unit B, Policlinico Umberto I of Rome, from June 2015 to December 2018. All patients underwent baseline thyroid function evaluations repeated monthly. RESULTS: The cohort consisted of 126 patients (66.7% male, mean age 66.4 ± 9.7 years). One hundred and seven received nivolumab and 19 pembrolizumab. Twenty-three per cent of patients experienced TAEs (mainly CTCAE grade 1), with hypothyroidism in 15.1% (subclinical: 11.9%, overt: 3.2%) and hyperthyroidism in 8.0% (subclinical: 4.8%, overt: 3.2%). Median time to TAE onset was 8.7 ± 6.8 weeks (10.4 ± 7.6 weeks for hypothyroidism, 5.4 ± 3.0 weeks for hyperthyroidism). Most TAEs (89.7%) appeared within the first 3 months, none after 8 months. Most hypothyroid patients (63.2%) had previously been treated with a tyrosine kinase inhibitor (TKI). Logistic regression analysis showed that pretreatment with a TKI was a major predisposing factor for the development of hypothyroidism (OR 9.2, 95% CI: 1.4-59.9, P = .020). CONCLUSIONS: TAEs are common during anti-PD-1 therapy and usually occur within the first 3 months of treatment. This is the first study evaluating the impact of previous oncologic therapies on TAEs, identifying TKI as a major risk factor for the development of hypothyroidism in patients treated with anti-PD-1.

Late Effects of Parasellar Lesion Treatment: Hypogonadism and Infertility.

Central hypogonadism, also defined as hypogonadotropic hypogonadism, is a recognized complication of hypothalamic-pituitary-gonadal axis damage following treatment of sellar and parasellar masses. In addition to radiotherapy and surgery, CTLA4-blocking antibodies and alkylating agents such as temozolomide can also lead to hypogonadism, through different mechanisms. Central hypogonadism in boys and girls may lead to pubertal delay or arrest, impairing full development of the genitalia and secondary sexual characteristics. Alternatively, cranial irradiation or ectopic hormone production may instead cause early puberty, affecting hypothalamic control of the gonadostat. Given the reproductive risks, discussion of fertility preservation options and referral to reproductive specialists before treatment is essential. Steroid hormone replacement can interfere with other replacement therapies and may require specific dose adjustments. Adequate gonadotropin stimulation therapy may enable patients to restore gametogenesis and conceive spontaneously. When assisted reproductive technology is needed, protocols must be tailored to account for possible long-term gonadotropin insufficiency prior to stimulation. The aim of this review was to provide an overview of the risk factors for hypogonadism and infertility in patients treated for parasellar lesions and to give a summary of the current recommendations for management and follow-up of these dysfunctions in such patients. We have also briefly summarized evidence on the physiological role of pituitary hormones during pregnancy, focusing on the management of pituitary deficiencies.

GH deficiency in cancer survivors in the transition age: diagnosis and therapy.

BACKGROUND: Survival rates among childhood cancer survivors (CCSs) have significantly risen in the last 40 years due to substantial improvements in treatment protocols. However, this improvement has brought with it serious late effects that frequently involve the endocrine system. Of the endocrine disorders, GH deficiency (GHD) is the most common among CCSs as a consequence of a history of cancers, surgery, and/or radiotherapy involving the hypothalamo-pituitary region. METHODS: A comprehensive search of English language articles regardless of age was conducted in the MEDLINE database between December 2018 and October 2019. We selected all studies on GH therapy in CCSs during the transition age regarding the most challenging topics: when to retest; which diagnostic tests and cut-offs to use; when to start GH replacement therapy (GHRT); what GH dose to use; safety; quality of life, compliance and adherence to GHRT; interactions between GH and other hormonal replacement treatments. RESULTS: In the present review, we provide an overview of the current clinical management of challenges in GHD in cancer survivors in the transition age. CONCLUSIONS: Endocrine dysfunction among CCSs has a high prevalence in the transition age and increase with time. Many endocrine disorders, including GHD, are often not diagnosed or under-diagnosed, probably due to the lack of specialized centers for the long-term follow-up. Therefore, it is crucial that transition specialized clinics should be increased in terms of number and specific skills in order to manage endocrine disorders in adolescence, a delicate and complex period of life. A multidisciplinary approach, also including psychological counseling, is essential in the follow-up and management of these patients in order to minimize their disabilities and maximize their quality of life.

Clinical presentation, management and follow-up of 83 patients with Leydig cell tumors of the testis: a prospective case-cohort study.

STUDY QUESTION: When should 'not so rare' Leydig cell tumors (LCTs) of the testis be suspected, diagnosed, and treated? SUMMARY ANSWER: LCTs are more frequent than generally believed, are associated with male infertility, cryptorchidism and gynecomastia, and should be treated conservatively (in compliant patients) with active surveillance, which appears to be a safe alternative to surgical enucleation. WHAT IS KNOWN ALREADY: Increasing referrals for testicular imaging have led to an increase in findings of LCTs. The features and natural history of these tumors remain largely unknown, as the available studies are small and heterogeneous. LCTs were previously treated aggressively and follow-up data are lacking. STUDY DESIGN, SIZE, DURATION: A case-cohort study of consecutive patients diagnosed with LCTs over a 10-year period was prospectively enrolled from 2009 to 2018 and compared to matched cohorts of patients with seminomas or no testicular lesions screened in the same timeframe. PARTICIPANTS/MATERIALS, SETTING, METHODS: Of the 9949 inpatients and outpatients referred for scrotal ultrasound, a total of 83 men with LCTs were included. Enrolled subjects underwent medical history and clinical examination and were asked to undergo routine blood tests, hormone investigations (FSH, LH, total testosterone, estradiol, inhibin B, sex hormone-binding globulin (SHBG), prolactin), and semen analysis. Patients who consented also underwent contrast-enhanced ultrasound, elastography, gadolinium-enhanced scrotal magnetic resonance imaging, and hCG stimulation test (5000 IU i.m.) with serum total testosterone and estradiol measured at 0, 24, 48, and 72 hours. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 83 patients diagnosed with LCTs were compared against 90 patients diagnosed with seminoma and 2683 patients without testicular lesions (NoL). LCTs were diagnosed by enucleation (48.2%), orchiectomy (13.3%), or clinical surveillance (38.5%). Testicular volume, sperm concentration, and morphology were lower (P = 0.001, P = 0.001, and P < 0.001, respectively) in patients with LCTs than in the NoL group. FSH, LH, and SHBG were higher and the testosterone/LH ratio was lower in LCTs than in the NoL group (P < 0.001). The LCT group showed higher SHBG (P = 0.018), lower sperm concentration (P = 0.029), and lower motility (P = 0.049) than the seminoma group. Risk factors for LCTs were cryptorchidism (χ2 = 28.27, P < 0.001), gynecomastia (χ2 = 54.22, P < 0.001), and low testicular volume (χ2 = 11.13, P = 0.001). Five cases were recurrences or bilateral lesions; none developed metastases during follow-up (median, 66 months). LIMITATIONS, REASONS FOR CAUTION: This study has some limitations. First, hCG and second-line diagnostic investigations were not available for all tumor patients. Second, ours is a referral center for infertility, thus a selection bias may have altered the baseline features of the LCT population. However, given that the comparison cohorts were also from the same center and had been managed with a similar protocol, we do not expect a significant effect. WIDER IMPLICATIONS OF THE FINDINGS: LCTs are strongly associated with male infertility, cryptorchidism, and gynecomastia, supporting the hypothesis that testicular dysgenesis syndrome plays a role in their development. Patients with LCTs are at a greater risk of endocrine and spermatogenesis abnormalities even when the tumor is resected, and thus require long-term follow-up and prompt efforts to preserve fertility after diagnosis.LCTs have a good oncological prognosis when recognized early, as tissue-sparing enucleation is curative and should replace orchiectomy. Conservative surgery and, in compliant patients, active surveillance through clinical and radiological follow-up are safe options, but require monitoring of testicular failure and recurrence. STUDY FUNDING/COMPETING INTEREST(S): The project was funded by the Ministry of University and Research Grant MIUR 2015ZTT5KB. There are no conflicts of interest. TRIAL REGISTRATION NUMBER: ALCeP trial (ClinicalTrials.gov Identifier: NCT01206270).

Impact of 3 Tesla MRI on interobserver agreement in clinically isolated syndrome: A MAGNIMS multicentre study.

BACKGROUND: Compared to 1.5 T, 3 T magnetic resonance imaging (MRI) increases signal-to-noise ratio leading to improved image quality. However, its clinical relevance in clinically isolated syndrome suggestive of multiple sclerosis remains uncertain. OBJECTIVES: The purpose of this study was to investigate how 3 T MRI affects the agreement between raters on lesion detection and diagnosis. METHODS: We selected 30 patients and 10 healthy controls from our ongoing prospective multicentre cohort. All subjects received baseline 1.5 and 3 T brain and spinal cord MRI. Patients also received follow-up brain MRI at 3-6 months. Four experienced neuroradiologists and four less-experienced raters scored the number of lesions per anatomical region and determined dissemination in space and time (McDonald 2010). RESULTS: In controls, the mean number of lesions per rater was 0.16 at 1.5 T and 0.38 at 3 T ( p = 0.005). For patients, this was 4.18 and 4.40, respectively ( p = 0.657). Inter-rater agreement on involvement per anatomical region and dissemination in space and time was moderate to good for both field strengths. 3 T slightly improved agreement between experienced raters, but slightly decreased agreement between less-experienced raters. CONCLUSION: Overall, the interobserver agreement was moderate to good. 3 T appears to improve the reading for experienced readers, underlining the benefit of additional training.

Is laparoscopic left adrenalectomy with the anterior submesocolic approach for Conn's or Cushing's syndrome equally safe and effective as the lateral and anterior ones?

BACKGROUND: The aim of the present study is to report and to compare the results of three different laparoscopic transperitoneal surgical approaches [lateral transperitoneal (LT), anterior transperitoneal (AT) and anterior transperitoneal submesocolic (ATS)] for the treatment of Conn's and Cushing's syndrome from left adrenal disease. METHODS: This study is a retrospective analysis of prospectively collected data. From 1994 to 2017, 535 laparoscopic adrenalectomies (LA) were performed. One hundred and sixty-four patients with Conn's or Cushing's syndrome underwent left LA. Patients were divided in three groups based on the approach: LT (Group A), AT (Group B) and ATS (Group C). RESULTS: The diagnosis was Conn's and Cushing's syndrome in 99 and 65 patients, respectively. LT was used in 13 cases, AT in 55 and ATS in 96. No significant differences in patient's gender, age and BMI were observed. Mean operative time was 117.6 ± 33.7, 107.6 ± 40.3 and 96.2 ± 47.5 min for Groups A, B and C, respectively. Conversion to open surgery was observed in 4 Group C patients (4.1%). Morbidity occurred in 2 Group B (2%) and in 5 Group C patients (5.2%). CONCLUSIONS: In case of Conn's or Cushing's syndrome, left LA with ATS approach is equally safe and effective as compared to the LT and AT approaches. Early control of the adrenal vein with minimal gland manipulation and limited surgical dissection are the major advantages of the submesocolic approach. Even if statistically significant differences are not observed, postoperative results are the same as those reported in the literature with other approaches.

Laparoscopic bilateral anterior transperitoneal adrenalectomy: 24 years experience.

BACKGROUND: The aim of this study is to evaluate the feasibility, safety, advantages and surgical outcomes of laparoscopic bilateral adrenalectomy (LBA) by an anterior transperitoneal approach. METHODS: From 1994 to 2018, 552 patients underwent laparoscopic adrenalectomy, unilateral in 531 and bilateral in 21 patients (9 females and 12 males). All patients who underwent LBA were approached via a transperitoneal anterior route and form our study population. Indications included: Cushing's disease (n = 11), pheochromocytoma (n = 6), Conn's disease (n = 3) and adrenal cysts (n = 1). RESULTS: Mean operative time was 195 ± 86.2 min (range 55-360 min). Conversion was necessary in one case for bleeding. Three patients underwent concurrent laparoscopic cholecystectomy with laparoscopic common bile duct exploration and ductal stone extraction in one. Three postoperative complications occurred in one patient each: subhepatic fluid collection, intestinal ileus and pleural effusion. Mean hospital stay was 6.1 ± 4.7 days (range 2-18 days). CONCLUSIONS: In our experience, transperitoneal anterior LBA was feasible and safe. Based on our results, we believe that this approach leads to prompt recognition of anatomical landmarks with early division of the main adrenal vein prior to any gland manipulation, with a low risk of bleeding and without the need to change patient position. Unlike the lateral approach, there is no need to mobilize the spleno-pancreatic complex on the left or the liver on the right. The ability to perform associated intraperitoneal procedures, if required, is an added benefit.

Role of Cerebellar Dentate Functional Connectivity in Balance Deficits in Patients with Multiple Sclerosis.

Purpose To prospectively investigate, by using resting-state functional magnetic resonance (MR) imaging, cerebellar dentate nuclei (DNs) functional connectivity abnormalities in multiple sclerosis (MS) to explore their impact on balance impairment in patients with MS, considering the role of DNs and their projections in maintaining balance, posture, and muscle tone, Materials and Methods All subjects provided written informed consent, and the protocol was approved by the university institutional review board. Twenty-five patients with relapsing-remitting MS and 20 healthy control subjects underwent a 3-T resting-state functional MR imaging and static posturography. The seed-based method was applied to identify the cerebellar DNs resting-state network; first-level and high-level analyses were performed by using software tools. Results Compared with control subjects, patients had worse postural stability and altered patterns of cerebellar DNs connectivity network, with decreased connectivity in caudate nuclei and thalami and increased connectivity in the cerebellum, pons, left amygdala, and orbitofrontal cortices (cluster level, family-wise error corrected, P < .05, z threshold > 2.3). In patients, the decreased connectivity in the left caudate nucleus was related with worse balance performance (cluster level, family-wise error corrected P < .05, z threshold > 1.96) regardless of age, lesion burden, and global clinical disability. Conclusion These results reveal abnormalities of corticocerebellar circuit connectivity in patients with MS as compared with control subjects and suggest that the decreased connectivity between the DN and the left caudate nucleus could play a role in balance impairment in MS. © RSNA, 2017.

Baseline morning cortisol level as a predictor of pituitary-adrenal reserve: a comparison across three assays.

CONTEXT: The short ACTH stimulation test (250 µg) is the dynamic test most frequently used to assess adrenal function. It is possible that a single basal cortisol could be used to predict the dynamic response, but research has been hampered by the use of different assays and thresholds. OBJECTIVE: To propose a morning baseline cortisol criterion of three of the most commonly used modern cortisol immunoassays - Advia Centaur (Siemens), Architect (Abbott) and the Roche Modular System (Roche) - that could predict adrenal sufficiency. DESIGN: Observational, retrospective cross-sectional study at two centres. PATIENTS AND MEASUREMENTS: Retrospective analysis of the results of 1019 Short Synacthen tests (SSTs) with the Advia Centaur, 449 SSTs with the Architect and 2050 SSTs with the Roche Modular System assay. Serum cortisol levels were measured prior to injection of 250 µg Synacthen and after 30 min. Overall, we were able to collate data from a total of 3518 SSTs in 3571 patients. RESULTS: Using receiver-operator curve analysis, baseline cortisol levels for predicting passing the SST with 100% specificity were 358 nmol/l for Siemens, 336 nmol/l for Abbott and 506 nmol/l for Roche. Utilizing these criteria, 589, 158 and 578 SSTs, respectively, for Siemens, Abbott and Roche immunoassays could have been avoided. CONCLUSIONS: We have defined assay-specific morning cortisol levels that are able to predict the integrity of the hypothalamo-pituitary-adrenal axis. We propose that this represents a valid tool for the initial assessment of adrenal function and has the potential to obviate the need for dynamic testing in a significant number of patients.

Dentate nucleus connectivity in adult patients with multiple sclerosis: functional changes at rest and correlation with clinical features.

BACKGROUND AND OBJECTIVE: The dentate nucleus, which is the largest of the cerebellar nuclei, plays a critical role in movement and cognition. The aim of our study was to assess any changes in dentate functional connectivity (FC) in adult relapsing remitting multiple sclerosis (RR-MS) patients and to investigate possible clinical correlates. MATERIALS AND METHODS: In all, 54 patients and 24 healthy subjects (HS) underwent multimodal magnetic resonance imaging (MRI), including diffusion tensor imaging (DTI), three-dimensional-T1-weighted and resting state (RS) functional images; they also underwent a cognitive evaluation, that is, attention and information processing speed, by means of the Paced Auditory Serial Addition Test (PASAT). Patients were also scored according to Expanded Disability Status Scale (EDSS). RS-MRI data were analysed using FMRIB Software Library (FSL) tools, with the seed-based method to identify dentate FC. RESULTS: When compared with HS, patients exhibited brain atrophy and widespread DTI abnormalities, as well as greater FC between the dentate nucleus and cortical areas, particularly in the frontal and parietal lobes. Within these areas, FC in patients correlated inversely with clinical impairment. Finally, FC correlated inversely with lesion load and microstructural brain damage. CONCLUSION: Our findings indicate that dentate FC at rest is altered in MS patients. Whether these functional changes are induced by the disease and play a compensatory role remains to be established.

The effect of inflammation and its reduction on brain plasticity in multiple sclerosis: MRI evidence.

Brain plasticity is the basis for systems-level functional reorganization that promotes recovery in multiple sclerosis (MS). As inflammation interferes with plasticity, its pharmacological modulation may restore plasticity by promoting desired patterns of functional reorganization. Here, we tested the hypothesis that brain plasticity probed by a visuomotor adaptation task is impaired with MS inflammation and that pharmacological reduction of inflammation facilitates its restoration. MS patients were assessed twice before (sessions 1 and 2) and once after (session 3) the beginning of Interferon beta (IFN beta), using behavioural and structural MRI measures. During each session, 2 functional MRI runs of a visuomotor task, separated by 25-minutes of task practice, were performed. Within-session between-run change in task-related functional signal was our imaging marker of plasticity. During session 1, patients were compared with healthy controls. Comparison of patients' sessions 2 and 3 tested the effect of reduced inflammation on our imaging marker of plasticity. The proportion of patients with gadolinium-enhancing lesions reduced significantly during IFN beta. In session 1, patients demonstrated a greater between-run difference in functional MRI activity of secondary visual areas and cerebellum than controls. This abnormally large practice-induced signal change in visual areas, and in functionally connected posterior parietal and motor cortices, was reduced in patients in session 3 compared with 2. Our results suggest that MS inflammation alters short-term plasticity underlying motor practice. Reduction of inflammation with IFN beta is associated with a restoration of this plasticity, suggesting that modulation of inflammation may enhance recovery-oriented strategies that rely on patients' brain plasticity. Hum Brain Mapp 37:2431-2445, 2016. © 2016 Wiley Periodicals, Inc.

Functional connectivity changes and their relationship with clinical disability and white matter integrity in patients with relapsing-remitting multiple sclerosis.

BACKGROUND AND OBJECTIVE: To define the pathological substrate underlying disability in multiple sclerosis by evaluating the relationship of resting-state functional connectivity with microstructural brain damage, as assessed by diffusion tensor imaging, and clinical impairments. METHODS: Thirty relapsing-remitting patients and 24 controls underwent 3T-MRI; motor abilities were evaluated by using measures of walking speed, hand dexterity and balance capability, while information processing speed was evaluated by a paced auditory serial addiction task. Independent component analysis and tract-based spatial statistics were applied to RS-fMRI and diffusion tensor imaging data using FSL software. Group differences, after dual regression, and clinical correlations were modelled with General-Linear-Model and corrected for multiple comparisons. RESULTS: Patients showed decreased functional connectivity in 5 of 11 resting-state-networks (cerebellar, executive-control, medial-visual, basal ganglia and sensorimotor), changes in inter-network correlations and widespread white matter microstructural damage. In multiple sclerosis, corpus callosum microstructural damage positively correlated with functional connectivity in cerebellar and auditory networks. Moreover, functional connectivity within the medial-visual network inversely correlated with information processing speed. White matter widespread microstructural damage inversely correlated with both the paced auditory serial addiction task and hand dexterity. CONCLUSIONS: Despite the within-network functional connectivity decrease and the widespread microstructural damage, the inter-network functional connectivity changes suggest a global brain functional rearrangement in multiple sclerosis. The correlation between functional connectivity alterations and callosal damage uncovers a link between functional and structural connectivity. Finally, functional connectivity abnormalities affect information processing speed rather than motor abilities.