Neurochemical Anatomy of Cushing's Syndrome.

The neurochemical anatomy underlying Cushing's syndrome is examined for regional brain metabolism as well as neurotransmitter levels and receptor binding of biogenic amines and amino acids. Preliminary studies generally indicate that glucose uptake, blood flow, and activation on fMRI scans decreased in neocortical areas and increased in subcortical areas of patients with Cushing's syndrome or disease. Glucocorticoid-mediated increases in hippocampal metabolism occurred despite in vitro evidence of glucocorticoid-induced decreases in glucose uptake or consumption, indicating that in vivo increases are the result of indirect, compensatory, or preliminary responses. In animal studies, glucocorticoid administration decreased 5HT levels and 5HT1A receptor binding in several brain regions while adrenalectomy increased such binding. Region-specific effects were also obtained in regard to the dopaminergic system, with predominant actions of glucocorticoid-induced potentiation of reuptake blockers and releasing agents. More in-depth neuroanatomical analyses are warranted of these and amino acid-related neurotransmission.

Adipose tissue in cortisol excess: What Cushing's syndrome can teach us?

Endogenous Cushing's syndrome (CS) is a rare condition due to prolonged exposure to elevated circulating cortisol levels that features its typical phenotype characterised by moon face, proximal myopathy, easy bruising, hirsutism in females and a centripetal distribution of body fat. Given the direct and indirect effects of hypercortisolism, CS is a severe disease burdened by increased cardio-metabolic morbidity and mortality in which visceral adiposity plays a leading role. Although not commonly found in clinical setting, endogenous CS is definitely underestimated leading to delayed diagnosis with consequent increased rate of complications and reduced likelihood of their reversal after disease control. Most of all, CS is a unique model for systemic impairment induced by exogenous glucocorticoid therapy that is commonly prescribed for a number of chronic conditions in a relevant proportion of the worldwide population. In this review we aim to summarise on one side, the mechanisms behind visceral adiposity and lipid metabolism impairment in CS during active disease and after remission and on the other explore the potential role of cortisol in promoting adipose tissue accumulation.

Cushing Syndrome Is Associated With Gut Microbial Dysbiosis and Cortisol-Degrading Bacteria.

CONTEXT: Cushing syndrome (CS) is a severe endocrine disease characterized by excessive secretion of cortisol with multiple metabolic disorders. While gut microbial dysbiosis plays a vital role in metabolic disorders, the role of gut microbiota in CS remains unclear. OBJECTIVE: The objective of this work is to examine the alteration of gut microbiota in patients with CS. METHODS: We performed shotgun metagenomic sequencing of fecal samples from 78 patients with CS and 78 healthy controls matched for age and body mass index. Furthermore, we verify the cortisol degradation capacity of Ruminococcus gnavus in vitro and identify the potential metabolite by LC-MC/MS. RESULTS: We observed significant differences in microbial composition between CS and controls in both sexes, with CS showing reduced Bacteroidetes (Bacteroides vulgatus) and elevated Firmicutes (Erysipelotrichaceae_bacterium_6_1_45) and Proteobacteria (Enterobacter cloacae). Despite distinct causes of hypercortisolism in ACTH-dependent and ACTH-independent CS, we found no significant differences in metabolic profiles or gut microbiota between the 2 subgroups. Furthermore, we identified a group of gut species, including R. gnavus, that were positively correlated with cortisol levels in CS. These bacteria were found to harbor cortisol-degrading desAB genes and were consistently enriched in CS. Moreover, we demonstrated the efficient capacity of R. gnavus to degrade cortisol to 11-oxygenated androgens in vitro. CONCLUSION: This study provides evidence of gut microbial dysbiosis in patients with CS and identifies a group of CS-enriched bacteria capable of degrading cortisol. These findings highlight the potential role of gut microbiota in regulating host steroid hormone levels, and consequently host health.

Comparison of adrenalectomy with conservative treatment on mild autonomous cortisol secretion: a systematic review and meta-analysis.

Objective: This systematic review and meta-analysis was conducted to compare the benefits of adrenalectomy and conservative treatment for comorbidities associated with mild autonomous cortisol secretion (MACS) in patients diagnosed with MACS. Background: MACS is the most common benign hormone-secreting functional adrenal incidentaloma. Overproduction of cortisol is observed in MACS patients, resulting in a variety of long-term health issues, including arterial hypertension (HTN), diabetes mellitus (DM), dyslipidemia, obesity, and osteoporosis; however, the classic clinical manifestations of Cushing's syndrome (CS) are not present. Methods: A systematic search was conducted using MEDLINE, Embase, Web of Sciences, and Scopus databases on December, 2023. Two reviewers independently extracted data and assessed the quality of the included articles. A meta-analysis was performed to compare the beneficial effects of adrenalectomy versus conservative management for MACS-related comorbidities. Results: Fifteen articles were included in this study, which evaluated 933 MACS patients (384 Adrenalectomy and 501 Conservative treatment, and 48 excluded due to incomplete follow-up duration). MACS diagnosis criteria were different among the included articles. All studies, however, stated that there must be no overt CS symptoms. Meta-analysis demonstrates the overall advantage of adrenalectomy over conservative treatment for MACS-related comorbidities (Cohen's d = -0.49, 95% CI [-0.64, -0.34], p = 0.00). Subgroup analysis indicated that the systolic blood pressure (pooled effect size = -0.81, 95% CI [-1.19, -0.42], p = 0.03), diastolic blood pressure (pooled effect size = -0.63, 95% CI [-1.05, -0.21], p = 0.01), and BMD (pooled effect size = -0.40, 95% CI [-0.73, -0.07], p = 0.02) were significantly in favor of adrenalectomy group rather than conservative treatment but no significant differences between the two treatment groups in other MACS-related comorbidities were reported. Conclusion: Despite the limited and diverse data, this study demonstrates the advantage of adrenalectomy over conservative treatment for MACS-related comorbidities.

Cortisol, Stress, and Disease-Bidirectional Associations; Role for Corticosteroid-Binding Globulin?

Selye described stress as a unified neurohormonal mechanism maintaining homeostasis. Acute stress system activation is adaptive through neurocognitive, catecholaminergic, and immunomodulation mechanisms, followed by a reset via cortisol. Stress system components, the sympathoadrenomedullary system, hypothalamic-pituitary-adrenal axis, and limbic structures are implicated in many chronic diseases by establishing an altered homeostatic state, allostasis. Consequent "primary stress system disorders" were popularly accepted, with phenotypes based on conditions such as Cushing syndrome, pheochromocytoma, and adrenal insufficiency. Cardiometabolic and major depressive disorders are candidates for hypercortisolemic etiology, contrasting the "hypocortisolemic symptom triad" of stress sensitivity, chronic fatigue, and pain. However, acceptance of chronic stress etiology requires cause-and-effect associations, and practical utility such as therapeutics altering stress system function. Inherent predispositions to stress system perturbations may be relevant. Glucocorticoid receptor (GR) variants have been associated with metabolic/neuropsychological states. The SERPINA6 gene encoding corticosteroid-binding globulin (CBG), was the sole genetic factor in a single-nucleotide variation-genome-wide association study linkage study of morning plasma cortisol, a risk factor for cardiovascular disease, with alterations in tissue-specific GR-related gene expression. Studies showed genetically predicted high cortisol concentrations are associated with hypertension and anxiety, and low CBG concentrations/binding affinity, with the hypocortisolemic triad. Acquired CBG deficiency in septic shock results in 3-fold higher mortality when hydrocortisone administration produces equivocal results, consistent with CBG's role in spatiotemporal cortisol delivery. We propose some stress system disorders result from constitutional stress system variants rather than stressors themselves. Altered CBG:cortisol buffering may influence interstitial cortisol ultradian surges leading to pathological tissue effects, an example of stress system variants contributing to stress-related disorders.

Evaluating the efficacy of surgical and conservative approaches in mild autonomous cortisol secretion: a meta-analysis.

Introduction: The management of Mild Autonomous Cortisol Secretion (MACS) remains a topic of debate among clinicians, with differing opinions on the effectiveness of surgical intervention compared to conservative treatment methods. This meta-analysis provides a comprehensive assessment of available literature to determine the most effective approach for treating this condition. Methods: On December 1, 2023, an exhaustive literature search of English databases Embase, PubMed, the Cochrane Library, Scopus, Web of Science, as well as the Chinese databases China HowNet, Wanfang Database, SinoMed Database, and Weipu Database using the keywords "Mild Autonomous Cortisol Secretion", "Subclinical Cushing's Syndrome", "Subclinical Hypercortisolism", "Mild Cortisol Autonomous Secretion", "Adrenal Incidentaloma", "Surgical Treatment" and "Adrenalectomy". The data were statistically analyzed using STATA version 15.0. Results: In this comprehensive analysis involving 629 patients with MACS, the therapeutic efficacy of adrenalectomy was evident. The meta-analysis results indicate that compared to conservative treatment, surgical intervention more effectively improves obesity indicators in patients: waist circumference (SMD=-0.62, 95% CI: -1.06 to -0.18), BMI (SMD=-0.41, 95% CI: -0.62 to -0.20), enhances glycemic control: fasting blood glucose (SMD=-0.47, 95% CI: -0.68 to -0.26), glycated hemoglobin (SMD=-0.66, 95% CI: -0.95 to -0.38), improves lipid metabolism: triglycerides (SMD=-0.45, 95% CI: -0.73 to -0.16), lowers blood pressure: systolic blood pressure (SMD=-1.04, 95% CI: -1.25 to -0.83), diastolic blood pressure (SMD=-0.89, 95% CI: -1.12 to -0.65), and ameliorates hormonal metabolic disorder: 24h urinary free cortisol (SMD=-1.10, 95% CI: -1.33 to -0.87), ACTH (SMD=2.30, 95% CI: 1.63 to 2.97). All these differences are statistically significant. Conclusion: This meta-analysis shows that, compared to conservative treatment, surgical treatment is more effective in improving obesity indicators, glycemic control, lipid metabolism, reducing blood pressure, and ameliorating hormonal metabolic disorders in patients with MACS. These statistically significant results highlight the importance of considering surgical intervention in the management of patients with MACS. Systematic review registration: https://www.crd.york.ac.uk/prospero, identifier CRD42023492527.

Prevalence and outcome of secondary hypogonadism in male patients with Cushing's syndrome and mild autonomous cortisol secretion.

BACKGROUND: Secondary hypogonadism (SH) is common in men with Cushing's syndrome (CS), but its impact on comorbidities is largely unknown and longitudinal data are scarce. If SH also affects men with mild autonomous cortisol secretion (MACS) is unknown. METHODS: We included 30 treatment-naïve adult men with CS and 17 men with MACS diagnosed since 2012. Hypogonadism was diagnosed based on total testosterone (TT) concentrations < 10.4 nmol/L and age-specific cut-offs. Outcomes were compared to age- and BMI-matched controls. In 20 men in remission of CS, a longitudinal analysis was conducted at 6, 12, and 24 months. RESULTS: Men with CS had significantly lower concentrations of TT, bioavailable T, and free T compared to controls (P < .0001) with lowest concentrations in ectopic CS. Likewise, TT was lower in men with MACS compared to controls. At baseline, 93% of men with CS and 59% of men with MACS had SH. Testosterone correlated negatively with late night salivary cortisol and serum cortisol pre- and post-1 mg dexamethasone suppression test. Following successful surgery, TT increased significantly (P = .001), normalising within 6 months. Despite normalisation, several RBC parameters remained lower in men with CS even 2 years after successful surgery. CONCLUSIONS: Secondary hypogonadism is common in men with CS and MACS but usually reversible after successful surgery. The persisting changes observed in RBC parameters need to be further investigated in larger cohorts and longer follow-up durations.

Fracture risk and bone health in adrenal adenomas with mild autonomous cortisol secretion/subclinical hypercortisolism: a systematic review, meta-analysis and meta-regression.

Adrenal adenomas/incidentalomas with mild autonomous cortisol secretion (MACS)/subclinical hypercortisolism (SH) are often associated with metabolic syndrome, glucocorticoid-induced osteoporosis, and fractures. In this background, the present systematic review and meta-analysis aimed to collate the available evidence and provide a summary of the effect of MACS/SH on bone health in terms of fractures, osteoporosis/osteopenia, microarchitecture, and bone turnover. PubMed/MEDLINE, Embase, and Web of Science databases were systematically searched for observational studies reporting prevalence of fractures, osteoporosis/osteopenia or data on bone microarchitecture/bone turnover markers (BTMs). Following literature search, 16 observational studies were included. Pooled prevalence of any fractures (vertebral and non-vertebral), vertebral fractures, and osteoporosis/osteopenia in MACS/SH were 43% [95% confidence intervals (CI): 23%, 62%], 45% (95% CI: 22%, 68%) and 50% (95% CI: 33%, 66%), respectively. On meta-regression, age, sex, 24-hour urinary free cortisol, and dehydroepiandrosterone-sulfate did not predict fracture risk. The likelihood of any fractures [odds ratio (OR) 1.61; 95% CI: 1.18, 2.20; P = 0.0026], vertebral fractures (OR 2.10; 95% CI: 1.28, 3.45; P = 0.0035), and osteoporosis/osteopenia (OR 1.46; 95% CI: 1.15, 1.85; P = 0.0018) was significantly higher in adrenal adenomas and MACS/SH than non-functional adrenal adenomas. Subjects with MACS/SH had significantly lower bone mineral density (BMD) at lumbar spine [mean difference (MD) -0.07 g/cm2; 95% CI: -0.11, -0.03; P = 0.0004) and femoral neck (MD -0.05 g/cm2; 95% CI: -0.08, -0.02; P = 0.0045) than their non-functional counterparts. Limited data showed no significant difference in BTMs. Publication bias was observed in the pooled prevalence of any fractures, vertebral fractures and pooled MD of femoral neck BMD. To conclude, people with adrenal adenomas/incidentalomas and MACS/SH are at a 1.5- to 2-fold higher likelihood of fractures and osteoporosis/osteopenia compared to non-functional adrenal adenomas and should routinely be screened for bone disease. Nevertheless, considering the modest sample size of studies and evidence of publication bias, larger and high-quality studies are required (CRD42023471045).

Mild autonomous cortisol secretion (MACS), often also referred to as subclinical hypercortisolism (SH), is usually associated with an underlying adrenal incidentaloma (AI), an adrenal mass incidentally found during abdomen imaging. Although signs of overt cortisol excess are lacking, subjects with MACS/SH often have features of metabolic syndrome, osteoporosis and fractures. The present systematic review and meta-analysis showed that the pooled prevalence of any fractures (vertebral and non­vertebral), vertebral fractures, and osteoporosis/osteopenia in MACS/SH were 43%, 45%, and 50%, respectively. People with adrenal adenomas/incidentalomas and MACS/SH are at a 1.5- to 2-fold higher likelihood of fractures and osteoporosis/osteopenia compared to non­functional adrenal adenomas. Besides, subjects with MACS/SH had significantly lower bone mineral density at lumbar spine and femoral neck than their non­functional counterparts. It is thus imperative to assess bone health in all subjects with MACS/SH.

Mild autonomous cortisol secretion: pathophysiology, comorbidities and management approaches.

The majority of incidentally discovered adrenal tumours are benign adrenocortical adenomas and the prevalence of adrenocortical adenomas is around 1-7% on cross-sectional abdominal imaging. These can be non-functioning adrenal tumours or they can be associated with autonomous cortisol secretion on a spectrum that ranges from rare clinically overt adrenal Cushing syndrome to the much more prevalent mild autonomous cortisol secretion (MACS) without signs of Cushing syndrome. MACS is diagnosed (based on an abnormal overnight dexamethasone suppression test) in 20-50% of patients with adrenal adenomas. MACS is associated with cardiovascular morbidity, frailty, fragility fractures, decreased quality of life and increased mortality. Management of MACS should be individualized based on patient characteristics and includes adrenalectomy or conservative follow-up with treatment of associated comorbidities. Identifying patients with MACS who are most likely to benefit from adrenalectomy is challenging, as adrenalectomy results in improvement of cardiovascular morbidity in some, but not all, patients with MACS. Of note, diagnosis and management of patients with bilateral MACS is especially challenging. Current gaps in MACS clinical practice include a lack of specific biomarkers diagnostic of MACS-related health outcomes and a paucity of clinical trials demonstrating the efficacy of adrenalectomy on comorbidities associated with MACS. In addition, little evidence exists to demonstrate the efficacy and safety of long-term medical therapy in patients with MACS.

Determinación de los niveles de cortisol salival en una muestra de sujetos de Santiago de Chile / Salivary cortisol among subjects with and without Cushing syndrome

Background: Salivary cortisol measurement is recommended as a screening mea-sure when a Cushing Syndrome is suspected. Theproposed cut-offpointfor aprobable diagnosis is 0.16 ug/dL. Aim: To determine salivary cortisol concentrations during the day inpatients with and without Cushing syndrome and with depression. Material and Methods: Salivary cortisol was measured by competitive enzyme immuno assay (EIA), in samples obtained at 8:00,15:00 and 23:00 h in 78 patients without Cushing syndrome, aged 40 ± 15years (28 males), 30 patients with depression aged 40 ± 12years (nine males) and four jemales with Cushing syndrome aged 42 ± 17 years. Results: Salivary cortisol was higher among patients with Cushing syndrome than the rest of patients. A salivary cortisol over the cut-off value of O.16 ug/dL was found in 42 percent of subjects without Cushing syndrome and in 33 percent of patients with depression. Median values among patients without Cushing syndrome, depression and with Cushing syndrome were 0.21 (range < 0.1-1.42), 0.2 (range 0,12-0.9) and 0.58 (range 0.37-1.1) ug/dL, respectively Conclusions: Salivary cortisol measured by EIA method was higher among patients with Cushing syndrome but there was a great overlap with values obtained in subjects without the syndrome.

Effect of one month ketoconazole treatment on GH, cortisol and ACTH release after ghrelin, GHRP-6 and GHRH administration in patients with cushing’s disease

GH responses to ghrelin, GHRP-6, and GHRH in Cushing’s disease (CD) are markedly blunted. There is no data about the effect of reduction of cortisol levels with steroidogenesis inhibitors, like ketoconazole, on GH secretion in CD. ACTH levels during ketoconazole treatment are controversial. The aims of this study were to compare the GH response to ghrelin, GHRP-6, and GHRH, and the ACTH and cortisol responses to ghrelin and GHRP-6 before and after one month of ketoconazole treatment in 6 untreated patients with CD. Before treatment peak GH (mg/L; mean ± SEM) after ghrelin, GHRP-6, and GHRH administration was 10.0 ± 4.5; 3.8 ± 1.6, and 0.6 ± 0.2, respectively. After one month of ketoconazole there was a significant decrease in urinary cortisol values (mean reduction: 75 percent), but GH responses did not change (7.0 ± 2.0; 3.1 ± 0.8; 0.9 ± 0.2, respectively). After treatment, there was a significant reduction in cortisol (mg/dL) responses to ghrelin (before: 30.6 ± 5.2; after: 24.2 ± 5.1). No significant changes in ACTH (pg/mL) responses before (ghrelin: 210.9 ± 69.9; GHRP-6: 199.8 ± 88.8) and after treatment (ghrelin: 159.7 ± 40.3; GHRP-6: 227 ± 127.2) were observed. In conclusion, after short-term ketoconazole treatment there are no changes in GH or ACTH responses, despite a major decrease of cortisol levels. A longer period of treatment might be necessary for the recovery of pituitary function.

Na doença de Cushing (DC), as respostas do GH à ghrelina, ao GHRP-6 e ao GHRH estão diminuídas. Não existem dados sobre o efeito da redução dos níveis de cortisol, após cetoconazol, na secreção de GH na DC. Nessa situação, os níveis de ACTH são variáveis. Os objetivos do estudo são comparar as respostas do GH à administração de ghrelina, GHRP-6 e GHRH, e de ACTH e cortisol à ghrelina e ao GHRP-6 antes e após um mês de tratamento com cetoconazol em 6 pacientes com DC não tratados. Antes do tratamento, o pico de GH (mg/L; média ± EPM) após a administração de ghrelina, GHRP-6 e GHRH foi de 10,0 ± 4,5; 3,8 ± 1,6 e 0,6 ± 0,2, respectivamente. Após um mês de cetoconazol, ocorreu diminuição significante do cortisol urinário (redução média: 75 por cento), mas as respostas de GH permaneceram inalteradas (7,0 ± 2,0; 3,1 ± 0,8; 0,9 ± 0,2, respectivamente). Após o tratamento, houve redução da resposta de cortisol (mg/dL) à ghrelina (antes: 30,6 ± 5,2; após: 24,2 ± 5,1), mas não ocorreram mudanças nas respostas de ACTH (pg/mL) (ghrelina antes: 210,9 ± 69,9; após: 159,7 ± 40,3; GHRP-6 antes: 199,8 ± 88,8; após: 227 ± 127,2). Assim, o tratamento a curto prazo com cetoconazol não modificou as respostas de GH ou ACTH, apesar da redução do cortisol. Para a recuperação da função hipofisária deve ser necessário um período de tratamento maior.

Cellular and molecular abnormalities of a macronodular adrenal hyperplasia causing beta-blocker-sensitive Cushing's syndrome

Cushing's syndrome due to ACTH-independent macronodular adrenal hyperplasia (AIMAH) can be associated with abnormal responses of aberrantly expressed adrenocortical receptors. This study aimed to characterize in vitro the pathophysiology of hypercortisolism in a b-blocker-sensitive Cushing's syndrome due to AIMAH. Cortisol secretion profile under aberrant receptors stimulation revealed hyperresponsiveness to salbutamol (beta2-adrenoceptor agonist), cisapride (5-HT4 receptor agonist), and vasopressin in AIMAH cultured cells, but not in normal adrenocortical cells. By RT-PCR, AIMAH tissues revealed beta2-adrenoceptor overexpression rather than ectopical expression. MC2R expression was similar in both AIMAH and normal adrenocortical tissues. Curiously, cortisol levels of AIMAH cells under basal condition were 15-fold higher than those of control cells and were not responsive to ACTH. Analysis of culture medium from AIMAH cells could detect the presence of ACTH, which was immunohistochemically confirmed. Finally, the present study of AIMAH cells has identified: a) cortisol hyperresponsiveness to catecholamines, 5-HT4 and vasopressin in vitro, in agreement with clinical screening tests; b) abnormal expression of beta2-adrenoceptors in some areas of the hyperplastic adrenal tissue; c) autocrine loop of ACTH production. Altogether, the demonstration of aberrant responses to hormonal receptors and autocrine hormone production in the same tissue supports the assumption of multiple molecular alterations in adrenal macronodular hyperplasia.

A síndrome de Cushing secundária à hiperplasia adrenal macronodular independente de ACTH (AIMAH) pode estar associada com respostas anômalas a estímulos sobre receptores hormonais expressos de maneira aberrante no córtex adrenal. O objetivo deste trabalho foi caracterizar a fisiopatologia do hipercortisolismo in vitro na síndrome de Cushing responsiva a beta-bloqueadores decorrente de AIMAH. Em cultura de células, a secreção de cortisol apresentou resposta aumentada ao salbutamol (agonista beta2-adrenérgico), à cisaprida (agonista de receptor 5-HT4) e à vasopressina, na AIMAH mas não no córtex adrenal normal. O estudo de receptores aberrantes por RT-PCR demonstrou que o gene do receptor beta2-adrenérgico estava superexpresso (e não expresso ectopicamente) nos fragmentos da AIMAH quando comparado ao tecido normal. A expressão de MC2R foi semelhante em ambos. Curiosamente, o nível basal de secreção de cortisol pelas células da AIMAH foi 15 vezes superior às células normais, não havendo resposta das células AIMAH ao estímulo com ACTH. A análise do meio de cultura das células AIMAH revelou a presença de ACTH, que foi confirmada por estudo imuno-histoquímico. Em suma, este estudo demonstrou: a) aumento dos níveis de cortisol in vitro em resposta a catecolaminas, 5-HT4 e vasopressina, correspondendo aos resultados dos testes clínicos para pesquisa de receptores aberrantes; b) expressão anormal de receptores beta2-adrenérgicos em algumas áreas de hiperplasia; c) produção autócrina de ACTH. Estes resultados envolvendo ativação de receptores aberrantes e estímulo hormonal autócrino no mesmo tecido favorecem a hipótese da existência de alterações moleculares múltiplas na hiperplasia adrenal macronodular.

Parathyroid hormone secretion in chronic human endogenous hypercortisolism

Osteoporosis is a common manifestation of Cushing's syndrome, but the mechanisms responsible for this abnormality have not been defined. With the objective of analyzing parathyroid hormone (PTH) secretion in chronic hypercortisolism (CH), we evaluated 11 healthy subjects and 8 patients with CH, 6 with Cushing's disease and 2 with adrenal adenoma. These volunteers were submitted to tests of PTH stimulation through hypocalcemia (EDTA), PTH suppression through hypercalcemia (iv and oral calcium), and evaluation of bone mineral density (BMD) by DEXA. During the test of PTH stimulation, the calcium and magnesium concentrations of the normal and CH groups were similar. Patients with CH showed an increased PTH response to the hypocalcemic stimulus compared to controls. PTH values were significantly higher in the CH group at 70 (17.5 ± 3.5 vs 10.2 ± 1.3 pmol/l, P = 0.04), and 120 min (26.1 ± 5.9 vs 11.3 ± 1.9 pmol/l, P = 0.008) of EDTA infusion. The area under the curve for PTH during EDTA infusion was also significantly higher in patients with CH than in normal subjects (1867 ± 453 and 805 ± 148 pmol l-1 2 h-1, P = 0.02). During the test of PTH suppression, calcium, magnesium and PTH levels of the patients with hypercortisolism and controls were similar. BMD was decreased in patients with hypercortisolism in the spine (0.977 ± 0.052 vs 1.205 ± 0.038 g/cm² in controls, P<0.01). In conclusion, our results show that subjects with CH present decreased bone mass mainly in trabecular bone. The use of dynamic tests permitted the detection of increased PTH secretion in response to a hypocalcemic stimulus in CH patients that may probably be involved in the occurrence of osteoporosis in this state

Salivary cortisol as a tool for physiological studies and diagnostic strategies

Salivary cortisol is an index of plasma free cortisol and is obtained by a noninvasive procedure. We have been using salivary cortisol as a tool for physiological and diagnostic studies, among them the emergence of circadian rhythm in preterm and term infants. The salivary cortisol circadian rhythm in term and premature infants was established between 8 and 12 postnatal weeks. In the preterm infants the emergence of circadian rhythm was parallel to the onset of sleep rhythm. We also studied the use of salivary cortisol for screening for Cushing's syndrome (CS) in control and obese outpatients based on circadian rhythm and the overnight 1 mg dexamethasone (DEX) suppression test. Salivary cortisol was suppressed to less than 100 ng/dl after 1 mg DEX in control and obese patients. A single salivary cortisol measurement at 23:00 h and again after 1 mg DEX above the 90th percentile of the obese group values had sensitivity and specificity of 93 and 93 percent (23:00 h), and 91 and 94 percent (after DEX), respectively. The sensitivity improved to 100 percent when we combined both parameters. We also studied 11 CS children and 21 age-matched primary obese children for whom salivary cortisol sensitivity and specificity were 100/95 percent (23:00 h), and 100/95 percent (1 mg DEX), respectively. Similar to adults, sensitivity and specificity of 100 percent were obtained by combining 23:00 h and 1 mg DEX. The measurement of salivary cortisol is a useful tool for physiological studies and for the diagnosis of CS in children and adults on an outpatient basis.

Síndrome de Cushing / Cushing Syndrome

Paciente masculino de 38 anos notou aumento do peso (principalmente com acúmulo de gordura abdominal) e fraqueza muscular, de início há cerca de 2 anos. Nesse período, observou também aumento de volume da face, acne no dorso, perda de pêlos nas pernas e queda de cabelos, além do aparecimento de estrias violáceas no abdômen. Há 1 ano foi diagnosticada hipertensão arterial sistêmica e diabetes melito