1,720,983 research outputs found
Coagulopathy in Cushing's syndrome.
Full text linkA hypercoagulable state and its consequent increased incidence of thromboembolic complications are reported in patients with Cushing's syndrome (CS). These alterations are related to cortisol excess that induces prothrombotic changes in blood by several and complex mechanisms including increased levels of clotting factors, mainly factor VIII and von Willebrand factor (VWF) and impaired fibrinolytic capacity. However, it has recently been observed that the increase in VWF levels is not a constant feature of CS and that VWF response to glucocorticoids is genetically determined and depends on the presence of particular polymorphisms in the VWF gene promoter. The risk of venous thromboembolism is moreover enhanced in patients with CS by additional endogenous and exogenous risk factors such as obesity, bed rest, surgery and invasive diagnostic procedures like inferior petrosal sinus (IPS) sampling. In line with all these data, patients with active CS should be treated as having a prothrombotic disorder and undergo antithrombotic prophylaxis during IPS sampling. Special care should be taken in the immediate perioperative period in order to avoid thromboembolic events. In the absence of prospective randomized trials, preventive antithrombotic treatment (best with heparin) during IPS sampling and low-dose heparin treatment early after surgery should be suggested
Association of glucocorticoid receptor polymorphism A3669G with decreased risk of developing diabetes in patients with Cushing's syndrome
No full textObjective
Glucocorticoid receptor (GR) polymorphisms alter glucocorticoid (GC) sensitivity and have been associated with altered metabolic profiles. We evaluate the prevalence of the four GR (NR3C1) polymorphisms BclI, N363S, ER22/23EK, and A3669G in patients with Cushing's syndrome (CS) compared with healthy controls (HC) and we investigate their role in the development of metabolic abnormalities in patients with CS according to their hormonal profile.
Patients and methods
Sixty-one patients with CS and 71 sex- and age-matched HC were genotyped.
Results
BclI variant was markedly higher in patients with CS compared with HC (62 vs 41%, P<0.05) while no significant differences were found among other polymorphisms. A very low frequency of N363S and the ER22/23EK was observed.
In CS patients, despite the significantly increased levels of morning serum cortisol in BclI carriers compared with wild type no clinical or metabolic differences were found.
In contrast, A3669G GR carriers showed a significantly reduced prevalence of type 2 diabetes mellitus compared with wild type (19 vs 68%, P=0.001) despite the higher levels of both serum morning (21.7±6 vs 27.3±8.6 μg/dl, P=0.009) and midnight cortisol (18.8±5.8 vs 24.0±8.0 μg/dl, P=0.01). The negative association between diabetes and A3669G GR polymorphism remained significant when data were adjusted for potential confounding factors.
Conclusions
The A3669G polymorphism of the GR gene plays a protective role in patients with CS, attenuating the effects of GC excess on glucose metabolism as shown by their reduced risk of diabetes
Pathophysiology of dyslipidemia in Cushing's syndrome.
Full text linkDyslipidemia seems to be less frequent than other metabolic comorbidities in human Cushing's syndrome. Nevertheless, it plays an important role in determining the global cardiovascular risk in overt and subclinical Cushing's syndrome. In Cushing's syndrome, there is an increase of triglyceride and total cholesterol levels whereas HDL can be at variable levels. Overt and subclinical Cushing's syndrome share many features with metabolic syndrome including insulin resistance, abnormal fasting glucose levels, hypertension, obesity and dyslipidemia. The pathogenetic mechanisms are multifactorial, including direct and indirect cortisol action on lipolysis, free fatty acid production and turnover, very-low-density lipoprotein synthesis and fatty accumulation in the liver. AMP-activated protein kinase mediates many of glucocorticoid-induced metabolic changes. Insulin resistance plays a key role in determining lipid abnormalities. Other hormonal changes are involved including growth hormone, testosterone in men and estrogen in women, catecholamines and cytokines. In vitro, cortisol increases lipoprotein lipase in adipose tissues and particularly in visceral fat where lipolysis is activated, resulting in the release of free fatty acids into the circulation. The increase of free fatty acids may enhance the accumulation of hepatic lipids reducing glucose uptake and activating various serine kinases which results in decreased insulin signaling. Moreover, mice with a liver-specific disruption of the glucocorticoid receptor had diminished hepatic triglycerides levels. In humans, a high prevalence (up to 20%) of hepatic steatosis was also reported in patients with Cushing's syndrome. Genetic variations in the glucocorticoid receptors may also affect the activity of cortisol, lipid metabolism and cardiovascular risk
Human corticotropin releasing hormone test performance in the differential diagnosis between Cushing's disease and pseudo-Cushing state is enhanced by combined ACTH and cortisol analysis.
No full textAbstract
OBJECTIVE:
Corticotropin releasing hormone (CRH) test does not reliably distinguish Cushing's disease (CD) from normality or pseudo-Cushing state (PC). We assessed whether this could be achieved with a novel approach while preserving the ability of the test to distinguish CD from ectopic ACTH syndrome (EAS). Design Retrospective/prospective study.
SUBJECTS AND METHODS:
We studied 51 subjects with CD, 7 with EAS, 26 with PC, and 31 controls (CT). Human CRH (hCRH) test was performed at 0830 h by measuring plasma ACTH and serum cortisol at -15, 0, 15, 30, 45, 60, 90, and 120 min.
RESULTS:
The area under the curve-ACTH exhibited a significant negative correlation with baseline serum cortisol in CT and PC, but not in CD or EAS patients. ACTH response to hCRH was blunted in PC compared with CT, whereas peak serum cortisol was higher in PC than in CT subjects. These findings suggested that ACTH-dependent Cushing's syndrome can be diagnosed by the presence of two hCRH test parameters and excluded if either or both are absent. Application of i) basal serum cortisol >12 microg/dl and peak plasma ACTH >54 pg/ml, or ii) peak serum cortisol >21 microg/dl and peak plasma ACTH >45 pg/ml, had 91.3% (95% confidence intervals (CI) 81-97.1) and 94.8% (CI 85.6-98.9) sensitivity and 98.2% (CI 90.6-99.9) and 91.2% (CI 80.7-97) specificity respectively, in diagnosing ACTH-dependent Cushing's syndrome. The >14% serum cortisol increase from mean baseline values to the mean of 15 and 30 min values in patients who were positive for the test completely discriminated between CD and EAS.
CONCLUSIONS:
Simultaneous plasma ACTH and serum cortisol analysis enables the hCRH test to distinguish CD from PC and from normality, while preserving its ability to discriminate CD from EAS
Pituitary adenomas, stem cells, and cancer stem cells: what's new?
No full textPurpose
To clarify the existence of pituitary stem cells (SCs) both in the embryonic and the postnatal gland and the role for SCs in pituitary adenomas.
Methods
This work, which does not address the pathogenesis of pituitary adenomas, reviews the latest research findings and discoveries on SCs in pituitary and cancer SCs (CSCs) in pituitary adenomas and discusses the involvement of the EMT.
Results
Several groups using different approaches and techniques have demonstrated the existence of SCs and CSCs and as they are major players in pituitary adenoma onset.
Conclusions
As in other benign and malignant tumors, the hypothesis that CSCs play a pivotal role in pituitary adenoma onset has been confirmed as well as the existence of a link between the epithelial-to-mesenchymal transition (EMT) process and CSC formation in epithelial tumors
Salivary cortisol is a useful tool to assess the early response to pasireotide in patients with Cushing's disease.
No full textPurpose: Late night salivary cortisol (LNSC) is useful for diagnosing hypercortisolism and monitoring patients with Cushing's disease (CD) following pituitary surgery. It may also be a better index of cortisol secretion than serum cortisol or urinary free cortisol (UFC). No data regarding the role of LNSC in the early monitoring of patients with CD receiving drug therapy has been published. We investigated the value of LNSC in monitoring the short-term efficacy of pasireotide. Methods: Seven patients who were enrolled in a phase II study investigating the efficacy of pasireotide in CD (CSOM230B2208) were included in this analysis. Patients self-administered subcutaneous pasireotide 600 μg bid for 15 days. LNSC and UFC levels were assessed at baseline and day 15. Results: At baseline, all patients had elevated LNSC which was correlated significantly with UFC levels (r = 0.97, P = .0002). At day 15, LNSC was reduced in six patients. LNSC decreases were observed from day 1 (-20 %) and persisted until day 15 (overall mean reduction from baseline -51 %), with the greatest decrease on day 5 (-58 %). At day 15, UFC levels were decreased in all patients and normalized in one that restored also salivary cortisol rhythm. Conclusions: In patients with CD, pasireotide rapidly reduced and normalized both UFC and LNSC levels. LNSC may be a simple, non-invasive biomarker to assess the early response to pasireotide, particularly in determining whether cortisol rhythm is normalized in patients with normalized UFC levels
Up-to 5-year efficacy of pasireotide in a patient with Cushing's disease and pre-existing diabetes: literature review and clinical practice considerations.
No full textPurpose Pasireotide is a multi-receptor-targeted somatostatin analogue approved in the EU and in the US for the treatment of adults with Cushing's disease (CD). Pasireotide has a safety profile similar to other somatostatin analogues with the exception of hyperglycemia. In this report and literature review, the current understanding of predicting a positive treatment response to pasireotide in CD and the management of diabetes mellitus (DM) during pasireotide treatment are discussed and analyzed. Case presentation We report a case of a 55-year-old woman with CD and DM who benefitted from long-term pasireotide. The patient, who was enrolled in a phase III trial of the drug, showed early clinical improvements with pasireotide [900 μg subcutaneously twice daily (bid)] but was classified as a non-responder as urinary free cortisol (UFC) levels, were not normalized. Continuation of pasireotide for 12 months at an increased dose (1,200 μg bid) normalized UFC levels and restored cortisol rhythm. The initial deterioration in her blood glucose was managed with insulin and metformin; however, after 12 months' treatment with pasireotide her DM was well controlled with oral hypoglycemic agents. Five years later, the patient is still receiving pasireotide (300 μg bid) with no loss of clinical or biochemical efficacy and with continued glycemic control. Conclusions This case presentation indicates that uncontrolled UFC levels during the first few months of pasireotide treatment as well as worsening of glycemic control in patients with CD and DM are not always predictive of the efficacy and tolerability and appears to support the long-term continuation of pasireotide
Fracture risk assessment before and after resolution of endogenous hypercortisolism: Is the FRAX(®) algorithm useful?
No full textPurpose Fracture risk data following curative treatment of Cushing's syndrome (CS) are scarce and the role of bisphosphonates in bone recovery after remission is controversial. We evaluated the effects of hypercortisolism remission in bone recovery in CS. Then, we assessed if the FRAX (R) algorithm calculated before the cure can predict fracture risk after cure.
Methods Thirty-six patients with CS were retrospectively investigated. Bone turnover markers, bone mineral density (BMD) at the lumbar spine (L1-L4) and left femur (both neck and total hip were considered), and fracture risk using FRAX (R) algorithm with femoral neck BMD were evaluated at diagnosis and after a median follow-up of 24 months (range 12-108 months) from hypercortisolism remission. Data about bone active therapy were analyzed.
Results Hypercortisolism remission was associated with the improvement of all densitometric parameters and with the reduction of fracture risk. The percentage change in BMD and the fracture risk were not significantly different in bisphosphonate-treated vs. untreated patients. During follow-up, three fractured patients at baseline exhibited a new vertebral fracture. A baseline 10-year probability of major osteoporotic fractures (FRAX (R) Major) of 17 % was able to predict the occurrence of a new vertebral fracture during follow-up after cure with 100 % sensitivity, 77 % specificity, 81 % positive predictive value and 100 % negative predictive value.
Conclusions Osteoporosis and fracture risk may be reversible after curative treatment of CS, regardless of bisphosphonate therapy. We suggest applying the FRAX (R) algorithm to all active CS patients using a baseline FRAX (R) Major of 17 % as "intervention threshold"
The diagnostic accuracy of increased late night salivary cortisol for Cushing's syndrome: a real-life prospective study
No full textA prompt diagnosis of Cushing's Syndrome (CS) in high-risk populations is mandatory: 1-mg dexamethasone suppression test (1-mg DST), late night salivary cortisol (LNSC), and urinary-free cortisol (UFC) are recommended, despite thresholds calculated in retrospective studies. Our aim was to study the diagnostic accuracy of LNSC measured with chemiluminescence assay in a prospective study, confirming discrepancies with mass spectrometry (MS)
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