Diagnostic performance of salivary cortisol and serum osteocalcin measurements in patients with overt and subclinical Cushing's syndrome

Possible, probable, and certain hypercortisolism: A continuum in the risk of comorbidity

Hypercortisolism may be considered as a continuum in terms of both hormonal and cardiometabolic abnormalities. It ranges from cases with "normal" hormonal profile and low to intermediate risk of comorbidity to florid cases with clear clinical and hormonal evidence of glucocorticoid excess and clearly increased cardiometabolic risk. Even in patients with nonfunctioning adrenal incidentaloma (NFAI), defined as adrenal incidentaloma with normal results on the currently available hormonal test for evaluation of hypercortisolism, cardiometabolic and mortality risk is higher than in the general population without adrenal lesions. Mild hypercortisolism or autonomous cortisol secretion (ACS) is a term used for patients with adrenal incidentaloma and pathological dexamethasone suppression test (DST) results, but without specific clinical signs of hypercortisolism. It is widely known that this condition is linked to higher prevalence of several cardiometabolic comorbidities, including diabetes, hypertension, osteoporosis and metabolic syndrome, than in patients with NFAI or without adrenal tumor. In case of overt Cushing's syndrome, cardiovascular risk is extremely high, and standard mortality ratio is high, cardiovascular disease being the leading cause of death. The present review summarizes the current evidence for a detrimental cardiometabolic profile in patients with possible (NFAI), probable (ACS) and certain hypercortisolism (overt Cushing's syndrome).

Approach to the Patient With Adrenal Incidentaloma

Adrenal tumors are commonly discovered incidentally on cross-sectional abdominal imaging performed for reasons other than adrenal mass. Incidence of adrenal tumors increased 10-fold in the past 2 decades, with most diagnosed in older adults. In any patient with a newly discovered adrenal mass, determining whether the adrenal mass is malignant and whether it is hormonally active is equally important to guide the best management. Malignancy is diagnosed in 5% to 8% of patients with adrenal tumors, with a higher risk in young patients, if history of extra-adrenal malignancy, in those with large adrenal tumors with indeterminate imaging characteristics, and in bilateral adrenal tumors. Although overt hormone excess is uncommon in adrenal incidentalomas, mild autonomous cortisol secretion can be diagnosed in up to 30% to 50% of patients. Because autonomous cortisol secretion is associated with increased cardiovascular morbidity and metabolic abnormalities, all patients with adrenal incidentalomas require work up with dexamethasone suppression test. Management of adrenal tumors varies based on etiology, associated comorbidities, and patient's preference. This article reviews the current evidence on the diagnosis and evaluation of patients with adrenal mass and focuses on management of the most common etiologies of adrenal incidentalomas.

Osteopathy in mild adrenal Cushing's syndrome and Cushing disease

Pathophysiology and effects of endogenous glucocorticoid (GC) excess on skeletal endpoints as well as awareness and management of bone fragility are reviewed. Cushing's syndrome (CS) increase the risk of fracture affecting prevalently bone quality. Bone antiresorptive agents (SERMs, bisphosphonates and denosumab) as well as teriparatide increase bone mineral density and in some instances reduce fracture risk. Awareness and management of bone health in CS can be improved.

Biochemical diagnosis of Cushing's disease: Screening and confirmatory testing

Due to the variable clinical features and its rarity diagnosis of Cushing's disease (CD) is often delayed. Clearly, awareness for CD needs to be raised, accompanied by the availability of simple and accurate screening tests. Late-night salivary cortisol (LNSC), 1 mg dexamethasone suppression test (DST), and urinary free cortisol (UFC) have all been extensively studied, demonstrating high sensitivity and specificity for the diagnosis of Cushing's syndrome. However, each of those well-established tests has its own distinctive features, making it preferable in specific clinical conditions and patient groups. To choose the most appropriate test in individual patients, an expert endocrinologist should be consulted. This review will discuss the pitfalls for each of those tests.

Spironolactone reduces biochemical markers of bone turnover in postmenopausal women with primary aldosteronism

CONTEXT

Primary aldosteronism (PA) is the most frequent form of endocrine hypertension. Besides its deleterious impact on cardiovascular target organ damage, PA is considered to cause osteoporosis.

PATIENTS AND METHODS

We assessed bone turnover in a subset of 36 postmenopausal women with PA. 18 patients had unilateral PA and were treated by adrenalectomy, whereas 18 patients had bilateral PA and received mineralocorticoid receptor antagonist (MRA) therapy respectively. 18 age- and BMI-matched females served as controls. To estimate bone remodeling, we measured the bone turnover markers intact procollagen 1 N-terminal propeptide, bone alkaline phosphatase, osteocalcin and tartrate resistant acid phosphatase 5b in plasma by chemiluminescent immunoassays at time of diagnosis and one year after initiation of treatment.

STUDY DESIGN

Observational longitudinal cohort study.

SETTING

Tertiary care hospital.

RESULTS

Compared with controls, patients with PA had mildly elevated osteocalcin at baseline (p = 0.013), while the other bone markers were comparable between both groups. There were no differences between the unilateral and the bilateral PA subgroup. One year after initiation of MRA treatment with spironolactone bone resorption and bone formation markers had significantly decreased in patients with bilateral PA. In contrast, patients adrenalectomized because of unilateral PA showed no significant change of bone turnover markers.

CONCLUSION

This study shows that aldosterone excess in postmenopausal women with PA is not associated with a relevant increase of bone turnover markers at baseline. However, we observed a significant decrease of bone markers in patients treated with spironolactone, but not in patients treated by adrenalectomy.

Accuracy of Laboratory Tests for the Diagnosis of Cushing Syndrome

CONTEXT

The diagnosis of Cushing syndrome (CS) can be challenging. It remains to be determined which diagnostic tests are the most accurate.

OBJECTIVE

To summarize the accuracy of diagnostic tests for CS using contemporary meta-analytic techniques (hierarchical models).

DATA SOURCES

PubMed, Embase, Scopus, Web of Science, and the Cochrane Database of Systemic Reviews (inception until August 3, 2018).

STUDY SELECTION

Studies performed in adults that determined the accuracy of one or more diagnostic tests: overnight 1-mg dexamethasone suppression test (DST), 2-day low-dose DST (2d DST), 24-hour urinary free cortisol (UFC), late-night salivary cortisol (LNSC), midnight serum cortisol (MSC), and the dexamethasone-suppressed CRH (dex-CRH) and desmopressin (dex-DDAVP) tests.

DATA EXTRACTION

Two authors independently extracted data and performed methodological assessments.

DATA SYNTHESIS

One hundred thirty-nine studies (14 140 participants) were included in the analysis. The respective sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio (95% confidence interval [CI]) estimates include the following: DST 98.6% (96.9%-99.4%), 90.6% (86.4%-93.6%), 10.5 (7.2-15.3), and 0.016 (0.007-0.035); 2d DST 95.3% (91.3%-97.5%), 92.8% (85.7%-96.5%), 13.2 (6.47-27.1), and 0.051 (0.027-0.095); UFC 94.0% (91.6%-95.7%), 93.0% (89.0%-95.5%), 13.3 (8.47-21.0), and 0.065 (0.046-0.092); LNSC 95.8% (93.%-97.2%), 93.4% (90.7%-95.4%), 14.6 (10.3-20.7), and 0.045 (0.030-0.066); MSC 96.1% (93.5%-97.6%), 93.2% (88.1%-96.3%), 14.2 (7.96-25.2), and 0.042 (0.026-0.069); and dex-CRH 98.6% (90.4%-99.8%), 85.9% (67.6%-94.7%), 7.0 (2.80-17.6), and 0.016 (0.002-0.118). A single study evaluated dex-DDAVP. Meta-regression and a novel network meta-analytic approach suggest that DST is the most sensitive while UFC is the least sensitive.

CONCLUSIONS

All of the included diagnostic tests for CS are highly sensitive and specific. It appears that the DST is the most sensitive while the UFC is less sensitive. The specificity of all first-line tests appears comparable.

The Impact of Mild Autonomous Cortisol Secretion on Bone Turnover Markers

CONTEXT

Several studies have reported increased risk of fragility fractures in patients with mild autonomous cortisol secretion (MACS), discordant to the degree of bone density deterioration.

OBJECTIVE

To evaluate the effect of MACS on bone metabolism in patients with adrenal adenomas.

DESIGN

Cross-sectional study with prospective enrollment, 2014-2019.

SETTING

Referral center.

PATIENTS

213 patients with adrenal adenomas: 22 Cushing syndrome (CS), 92 MACS and 99 nonfunctioning adrenal tumors (NFAT).

MAIN OUTCOME MEASURES

Osteocalcin, procollagen I intact N-terminal (PINP), C-terminal telopeptide (CTX), sclerostin.

RESULTS

Patients with CS demonstrated lower markers of bone formation compared with patients with MACS and NFAT (CS vs MACS vs NFAT: mean osteocalcin 14.8 vs 20.1 vs 21.3 ng/mL [P < 0.0001]; mean PINP 34.8 vs 48.7 vs 48.5 µg/L [P = 0.003]). Severity of cortisol excess was inversely associated with sclerostin (CS vs MACS vs NFAT: mean sclerostin 419 vs 538 vs 624 ng/L, [P < 0.0001]). In a multivariable model of age, sex, body mass index, cortisol, and bone turnover markers, sclerostin was a significant predictor of low bone mass in patients with MACS (OR 0.63 [CI 95%, 0.40-0.98] for each 100 ng/L of sclerostin increase).After adrenalectomy, osteocalcin, CTX, and sclerostin increased by a mean difference of 6.3 ng/mL, 0.12 ng/mL, and 171 pg/mL (P = 0.02 for all), respectively.

CONCLUSIONS

Lower sclerostin level in patients with MACS reflects a reduction in osteocyte function or number associated with exposure to chronic cortisol excess. Increase in bone turnover markers after adrenalectomy suggests restoration of favorable bone metabolism.

Evaluation of bone health in patients with adrenal tumors

PURPOSE OF REVIEW

Adrenal tumors occur in 5% of population with higher prevalence in elderly. Patients with adrenal tumors present with overt hormonal excess in up to 15% of cases, and mild autonomous cortisol secretion in 30-40% of cases. Overt Cushing syndrome, mild autonomous cortisol secretion, pheochromocytoma, and primary aldosteronism have been associated with higher cardiovascular morbidity and mortality. Increasing experimental and clinical evidence also suggests that adrenal hormone excess is detrimental to bone health. This review aims to discuss the effect of cortisol, aldosterone, and catecholamine excess on bone metabolism, secondary osteoporosis, and fragility fractures.

RECENT FINDINGS

Several studies have reported that patients with hormonally active adrenal tumors demonstrate increased prevalence of fragility fractures incongruous to bone density scan findings. The utility of dual absorptiometry X-ray (DXA) in diagnosing secondary osteoporosis is unclear in patients with cortisol, aldosterone, and catecholamine excess. Trabecular bone score and bone turn over markers could serve as potential diagnostic tools in assessment of severity of bone disease in patients with hormonally active adrenal tumors.

SUMMARY

Adrenalectomy is the mainstay of therapy in patients with overt hormone production. Appropriate case detection strategies to identify patients at risk of fragility fractures are needed in patients not treated with adrenalectomy, such as bilateral primary aldosteronism and mild autonomous cortisol secretion.

Adrenal Hypercortisolism: A Closer Look at Screening, Diagnosis, and Important Considerations of Different Testing Modalities

Although prolonged hypercortisolism is associated with increased mortality and substantial morbidity, the clinical signs and symptoms are wide ranging and often nonspecific, contributing to challenges in diagnosis, as well as treatment delays. Greater awareness is needed among clinicians to help identify which patients should undergo biochemical screening for excess cortisol. Several biochemical tests are available, each with important caveats that should be considered in the context of the individual patient. Cortisol secretion varies widely, further complicating the biochemical diagnosis of hypercortisolism, which relies on the use of definitive cutoff values. Patients with hypercortisolism resulting from adrenal adenomas, including those discovered incidentally, often do not present with overt Cushingoid features (plethora, striae, muscle weakness, moon facies, etc.). However, the consequences of prolonged exposure to even slight elevations in cortisol levels are profound, including increased risk of diabetes, hypertension, fractures, cardiovascular events, and mortality. Because most cases of hypercortisolism resulting from an adrenal adenoma can be managed, it is imperative to identify patients at risk and initiate testing early for the best outcomes. The aim of this report is to increase awareness of the indications for screening for hypercortisolism and to review the biochemical screening tests and diagnosis for hypercortisolism associated with adrenal adenomas.

The diagnostic accuracy of increased late night salivary cortisol for Cushing's syndrome: a real-life prospective study

INTRODUCTION AND AIM

A 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).

MATERIALS AND METHODS

We enrolled 117 controls and 164 suspected CS (CS = 47, non-CS = 117). In case of increased LNSC, high clinical suspicion of CS or adrenal incidentaloma, patients were hospitalized to exclude/confirm CS.

RESULTS

LNSC levels were higher in patients with suspected CS, CS, and non-CS than controls. Considering 16 nmol/L as threshold for CS, overall LNSC revealed SE 97% and SP 84% in the whole group of subjects considered, achieving positive/negative likelihood ratio of 5.56/0.045, respectively. 35 out of 81 subjects with increased LNSC were non-CS (15 diabetic and 20 obese): considering only those patients with increased likelihood to have a CS (the non-CS patients) SP decreased to 70%, and further reduced to 60% if we discharged subjects with adrenal incidentaloma. MS analyses reduced partially the number of false-positive LNSC.

CONCLUSIONS

LNSC measured in automated chemiluminescence is reliable in clinical practice: it present a high diagnostic accuracy to exclude hypercortisolism in patients with normal cortisol levels. MS could be used to reduce the number of false-positive results; nevertheless, some non-CS subjects with functional hypercortisolism could have a mild impairment of cortisol rhythm.

Association of Serum Total Osteocalcin Concentrations With Endogenous Glucocorticoids and Insulin Sensitivity Markers in 12-Year-Old Children: A Cross-Sectional Study

Background: Osteocalcin (OC) is an osteoblast-derived marker of bone turnover that has recently been linked to glucose metabolism, glucocorticoid action, and cardiovascular risk. Objective: We determined whether serum total OC (tOC) is associated with cardiometabolic factors, such as insulin sensitivity (IS) markers and endogenous glucocorticoids in 12-year-old children. In addition, we assessed whether low birth weight or exposure to maternal preeclampsia affect tOC concentrations. Methods: In this cross-sectional study, 192 children (109 girls) were studied at 12 years of age. Seventy of them had been born small (SGA), 78 appropriate for gestational age (AGA), and 44 from preeclamptic pregnancies (PRE) as AGA. Blood pressure was measured, and fasting blood samples were collected for markers of glucose metabolism, osteoblast, adipocyte, and adrenocortical function. IS was estimated by Quantitative Insulin Sensitivity Check Index (QUICKI). Free cortisol index (FCI) was calculated as serum cortisol/corticosteroid binding globulin. Results: The highest tOC concentrations were detected in midpubertal children (Tanner B/G stage 3). The children in the highest tOC quartile (n = 48) had lower body mass index (BMI), waist-to-height ratio, diastolic blood pressure, leptin, cortisol/cortisone ratio and FCI, and higher insulin-like growth factor I (IGF-I), IGF-binding protein-1 (IGFBP-1), IGFBP-3, and alkaline phosphatase (ALP) than those in the lower tOC quartiles (p < 0.02 for all). QUICKI was similar in these subgroups. In logistic regression analysis, pubertal developmental stages 2 and 3, high ALP, IGF-I, and low FCI and BMI (p < 0.02 for all) were associated independently with higher tOC. The means of serum tOC and IS markers were similar in the SGA, AGA, and PRE subgroups. Conclusions: In both sexes, the highest tOC levels were detected in midpubertal children reflecting the fast pubertal growth phase. Higher tOC levels were associated with lower BMI and FCI, whereas no association was found with IS. Birth weight or exposure to preeclampsia had no effect on tOC concentrations.

Evaluation of salivary oxidative parameters in overweight and obese young adults

Background

Obesity is characterized by a deposition of abnormal or excessive fat in adipose tissue, and is linked with a risk of damage to several metabolic and pathological processes associated with oxidative stress. To date, salivary oxidative biomarkers have been minimally explored in obese individuals. Thus, the aim of this study was to assess the concentrations of salivary oxidative biomarkers (ferric-reducing antioxidant power, uric acid, sulfhydryl groups) and lipid peroxidation in obese and overweight young subjects.

Materials and methods

Levels of lipid peroxidation, ferric-reducing antioxidant power, uric acid, and SH groups were determined in the saliva and serum of 149 young adults, including 54 normal weight, 27 overweight, and 68 obese individuals. Anthropometric measurements were also evaluated.

Results

Salivary levels of ferric-reducing antioxidant power, sulfhydryl groups, and lipid peroxidation, as well as serum levels of ferric-reducing antioxidant power, uric acid, and lipid peroxidation were higher in obese patients when compared with individuals with normal weight. There were correlations between salivary and serum ferric-reducing antioxidant power and salivary and serum uric acid in the obese and normal-weight groups.

Conclusions

Our results indicate that the increase in salivary levels of ferric-reducing antioxidant power, sulfhydryl groups, and lipid peroxidation, and serum levels of ferric-reducing antioxidant power, uric acid, and lipid peroxidation could be related to the regulation of various processes in the adipose tissue. These findings may hold promise in identifying new oxidative markers to assist in diagnosing and monitoring overweight and obese patients.

Diagnostic performance of osteocalcin measurements in patients with endogenous Cushing's syndrome

The aim of this study was to evaluate the diagnostic performance of osteocalcin (OC), as measured by automated electrochemiluminescence immunoassay (ECLIA), in identifying Cushing's syndrome (CS) in two separate populations: among obese and overweight subjects and among women of postmenopausal age with osteoporosis. Among the 106 referral patients with obesity, CS was confirmed in 42 cases. The patients of the referred population provided late-night salivary cortisol (LNSC), underwent low-dose dexamethasone suppression testing (DST) and were further evaluated until CS was pathologically confirmed. A threshold of OC-8.3 ng ml(-1) differentiated CS among obese and overweight subjects with a sensitivity of 73.8% (95% confidence interval (CI) 58.9-84.7) and a specificity of 96.9% (95% CI 89.3-99.1). The total area under the receiver operating characteristic curve (AUC) was 0.859 (95% CI 0.773-0.945), which was lower than LNSC or DST (P=0.01). In the retrospective portion of the study, the OC levels were evaluated in 67 subjects with newly diagnosed postmenopausal osteoporosis and in 23 patients (older than 45) with newly diagnosed CS and osteoporosis (presence of low traumatic fractures or T-score P-2.5). The diagnostic performance of OC for osteoporosis due to CS was within an AUC of 0.959 (95% CI 0.887-1.00). A threshold for OC of 8.3 ng ml-1 yielded a sensitivity of 95.4% (95% CI 78.2-99.2%) and a specificity of 98.5% (95% CI 92.0-99.7%). Thus, osteocalcin could be used in the diagnostic testing for endogenous hypercortisolism in patients referred to exclude CS and to identify CS among patients of postmenopausal age with osteoporosis.

Adenosine deaminase, dipeptidyl peptidase-IV activities and lipid peroxidation are increased in the saliva of obese young adult

BACKGROUND

Obesity is the hallmark of the metabolic syndrome representing a major global health problem. It is considered a state of chronic inflammation with minimal exploration of salivary biomarkers. Thus, the intent of the present study was to assess the activities of salivary dipeptidyl peptidase IV (DPP-IV), adenosine deaminase (ADA) and lipid peroxidation in obese young and overweight young subjects.

METHODS

ADA, DPP-IV activities and lipid peroxidation were investigated in saliva, as well as insulin, glucose, HbA1c, HOMA and anthropometric measurements in 149 young adults, including 54 with normal weight, 27 overweight and 68 obese subjects.

RESULTS

Salivary ADA and DPP-IV activities as well as lipid peroxidation were higher in patients with obesity compared to the normal weight group. Correlations between ADA/DPP-IV activities, lipid peroxidation/ADA activity, ADA activity/hip circumference and BMI/weight were observed.

CONCLUSIONS

Our results indicate that the increase in the salivary ADA and DPP-IV activities as well as in the lipid peroxidation could be related of the regulation to various aspects of adipose tissue function and inflammatory obesity. It is suggested that these salivary biomarkers may be used as biochemical test in clinical abnormalities present in obesity, in the absence of oral inflammatory diseases.

Subclinical hypercortisolism in adrenal incidentaloma

PURPOSE OF REVIEW

The article aims to update the reader on current developments in the area of adrenal incidentaloma complicated by subclinical hypercortisolism. We will discuss different diagnostic strategies and complications associated with this disease, and address the conflicting opinions related to the treatment of these patients.

RECENT FINDINGS

Depending on diagnostic criteria used, between 30 and 50% of patients with adrenocortical incidentaloma have biochemical hypercortisolism, but lack classical external features of Cushing's syndrome. The challenge facing the clinician is that in the sixth and seventh decade of life hypertension, diabetes, osteoporosis and obesity are common and establishing whether these are directly related to the low-grade excess cortisol secretion in a given individual is not straightforward. Nevertheless, this subclinical hypercortisolism has been found to be associated with multiple cardiovascular risk factors, an increased predisposition to cardiovascular events and a higher mortality rate. The dilemma is that it is not established whether surgical excision of the adrenal adenoma in a given individual will improve these complications, and data demonstrate that surgical studies are conflicting.

SUMMARY

Subclinical hypercortisolism is associated with multiple complications and definite guidelines for diagnosis are necessary. Prospective, randomized controlled studies are needed to ascertain whether medical or surgical interventions are justified, and in which patients.

Cushing’s disease: the clinical features, diagnostics, differential diagnostics, and methods of treatment

The present guidelines on diagnostics, differential diagnostics, and methods of treatment of Cushing’s disease have been developed by a group of Russian specialists.

DHEAS for the prediction of subclinical Cushing's syndrome: perplexing or advantageous?

The diagnostic accuracy of dehydroepiandrosterone sulfate (DHEAS) to predict subclinical Cushing's syndrome (sCS) has been a matter of debate. The primary objective of this study was to assess the diagnostic power of DHEAS in predicting sCS. This retrospective study was conducted in a tertiary referral center and based on subjects referred between 2004 and 2014. Data of 249 subjects with adrenal incidentalomas were evaluated. We also reviewed 604 DHEAS measurements from adults, which were performed during the same period in our laboratory (LB group). Adrenocortical function, tumor size, and clinical characteristics were assessed. We diagnosed sCS in 15.2 % of the participants in the presence of ≥2 of the following; 1 mg dexamethasone suppression test >3.0 μg/dl, urinary free cortisol >70 μg/24 h, and corticotrophin (ACTH) <10 pg/ml. DHEAS levels were significantly reduced in patients with sCS (n = 38) compared to sCS (-) (n = 141) and LB groups (n = 604) (27.95, 65.90, and 66.80 µg/dl, respectively, p < 0.001) while age was comparable. The ROC curve analysis showed that the cut-off of the DHEAS with the best diagnostic accuracy for detecting sCS was 40.0 μg/dl (SN, 68 %; SP, 75; PPV, 43 %; NPV, 90 %, AUC: 0.788, p < 0.001). Logistic regression assessed the impact of age, BMI, low DHEAS (<40 μg/dl), bilateral tumors, and tumor size on the likelihood of having sCS. The strongest predictor was low DHEAS, recording an OR of 9.41. DHEAS levels are inversely associated with the extent of cortisol excess. In subjects with intermediate laboratory findings, detection of low DHEAS could be advantageous for distinguishing sCS.

Common genetic variants of the human steroid 21-hydroxylase gene (CYP21A2) are related to differences in circulating hormone levels

Purpose

Systematic evaluation of the potential relationship between the common genetic variants of CYP21A2 and hormone levels.

Methods

The relationships of CYP21A2 intron 2 polymorphisms and haplotypes with diverse baseline and stimulated blood hormone levels were studied in 106 subjects with non-functioning adrenal incidentaloma (NFAI). The rationale for using NFAI subjects is dual: i) their baseline hormone profiles do not differ from those of healthy subjects and ii) hormone levels after stimulation tests are available.

Results

The carriers (N = 27) of a well-defined CYP21A2 haplotype cluster (c5) had significantly elevated levels of cortisol (p = 0.0110), and 17-hydroxyprogesterone (p = 0.0001) after ACTH stimulation, and 11-deoxycortisol after metyrapone administration (p = 0.0017), but the hormone values were in normal ranges. In addition, the carriers (N = 33) of the C allele of the rs6462 polymorphism had a higher baseline aldosterone level (p = 0.0006). The prevalence of these genetic variants of CYP21A2 did not differ between NFAI and healthy subjects.

Conclusions

The common CYP21A2 variants presumably exert the same effect on hormone levels in the healthy and disease-affected populations. Therefore, they may contribute to complex diseases such as some cardiovascular diseases, and may influence the genotype-phenotype correlation in patients with congenital adrenal hyperplasia (CAH) including the individual need for hormone substitution.

Significantly high level of late-night free cortisol to creatinine ratio in urine specimen in patients with subclinical Cushing's syndrome

OBJECTIVE

Absence of a late-night cortisol nadir is a consistent biochemical abnormality in patients with cortisol-producing adenoma. We evaluated the abnormality of late-night urinary free cortisol to creatinine ratio (late-night UFCCR) in patients with subclinical Cushing's syndrome (SCS).

METHODS

Fifty-eight patients with incidentally detected adrenocortical adenomas [SCS: 9; nonfunctioning adenoma (NF): 49] were enrolled as subjects. Values measured in all patients were urinary free cortisol accumulated between 9:00 p.m. and 11:00 p.m. (late-night UFCCR), serum cortisol at 11:00 p.m. (midnight serum cortisol: MSC), serum cortisol after 1-mg overnight dexamethasone suppression test (1 mg-DST) and 24-h urinary free cortisol (UFC).

RESULTS

Median late-night UFCCR value in SCS was significantly higher than that in NF (P < 0·001). Significant correlations were observed between late-night UFCCR and each of serum cortisol after 1 mg-DST and MSC (r = 0·537, P < 0·001 and r = 0·556, P < 0·001, respectively). There was no significant correlation between serum cortisol after 1 mg-DST and 24-h UFC (r = 0·211, P = 0·112). In receiver operating characteristic analysis for diagnosis of SCS, the areas under the curves of late-night UFCCR and 24-h UFC were 0·937 (95% confidence interval 0·865-1·008) and 0·726 (0·874-0·999), respectively. Late-night UFCCR cut-off value of 4·9 nmol/μmol Cre showed a sensitivity of 100% and a specificity of 76·6%.

CONCLUSION

Patients with SCS showed higher late-night UFCCR values than those with NF. Late-night UFCCR was significantly correlated with autonomous cortisol production findings. Diagnostic performance of late-night UFCCR was superior to 24-h UFC. These results suggest that late-night UFCCR might represent one of the simple and reliable tests for SCS diagnosis.

Serum extracellular secreted antagonists of the canonical Wnt/β-catenin signaling pathway in patients with Cushing's syndrome

Patients with endogenous hypercortisolism have higher sclerostin, but do not differ in Dickkopf 1 (Dkk1) or secreted frizzled-related protein 1 (SFRP1) levels as compared to healthy control.

INTRODUCTION

Endogenous Cushing's syndrome (CS), usually affecting young and otherwise healthy patients, is a good model to validate the effects of supraphysiological levels of glucocorticoids in humans. This study evaluates circulating levels of extracellular antagonists of the Wnt/β-catenin signaling pathway (sclerostin, Dkk1, SFRP1) in patients with CS versus healthy individuals.

METHODS

Forty patients with clinically and biochemically evident CS and 40 sex-, age-, and body mass index-matched healthy subjects provided fasting serum samples for sclerostin, SFRP1 and Dkk1, along with bone turnover markers.

RESULTS

Patients with CS had higher sclerostin levels (34.5 (30.3-37.1) pmol/L) versus healthy individuals (29.9 (24.3-36.8) pmol/L) (p = 0.032). Differences in sclerostin were due to the lack of lower sclerostin values rather than an increase in protein levels above the upper limits of the healthy control. The odds of sclerostin levels being higher than 30 pmol/L were greater in patients with CS as compared with the odds in healthy subjects (odds ratio = 3.81 95 % confidence interval 1.45-10.02) (p = 0.01). It coexisted with suppressed bone formation and unchanged bone resorption markers. Dkk1, SFRP1 did not differ from the control group.

CONCLUSIONS

Of all the tested proteins (sclerostin, Dkk1, SFRP1), only sclerostin showed a significant difference when contrasting CS with healthy subjects. Hypercortisolism might prevent the down-regulation of sclerostin. Targeting sclerostin seems to be a promising therapeutic approach to treating osteoporosis in patients with CS.

Performance of salivary cortisol in the diagnosis of Cushing's syndrome, adrenal incidentaloma, and adrenal insufficiency

OBJECTIVE

Salivary cortisol has recently been suggested for studies on the hypothalamic-pituitary-adrenal (HPA) axis. The lack of circadian rhythm is a marker of Cushing's syndrome (CS), and some authors have reported that low salivary cortisol levels may be a marker of adrenal insufficiency. The aim of our study was to define the role of salivary cortisol in specific diagnostic settings of HPA axis disease.

SUBJECTS AND METHODS

We analyzed morning salivary cortisol (MSC) and late-night salivary CORTISOL (LNSC) levels in 406 SUBJECTS: 52 patients with Cushing's disease (CD), 13 with ectopic CS, 17 with adrenal CS, 27 with CD in remission (a mean follow-up of 66±39 months), 45 with adrenal incidentaloma, 73 assessed as having CS and then ruled out for endogenous hypercortisolism, 75 with adrenal insufficiency, and 104 healthy subjects.

RESULTS

A LNSC value above 5.24  ng/ml differentiated CS patients from controls with high sensitivity (96.3%) and specificity (97.1%); we found higher LNSC levels in ectopic CS patients than in CD patients. We found no difference in MSC and LNSC levels between patients with CD in remission and healthy subjects. Both MSC and LNSC levels were higher in patients with adrenal incidentaloma than in healthy controls. A MSC value below 2.65 ng/ml distinguished patients with adrenal insufficiency from controls with high sensitivity (97.1%) and specificity (93.3%).

CONCLUSIONS

Salivary cortisol is a useful tool to assess endogenous cortisol excess or adrenal insufficiency and to evaluate stable CD in remission.

Glucocorticoid-induced osteoporosis: lessons from Cushing's syndrome

Glucocorticoid-induced osteoporosis (GIO) is the most frequent form of secondary bone disorders. Most of our knowledge on its pathogenesis and treatment has been obtained by investigating patients treated with exogenous glucocorticoids. This review will focus on the bone disorder in endogenous Cushing's syndrome, updating recent advances in its pathophysiology, diagnostic aspects and the various predictors which are important in determining bone mineral density (BMD) and fracture risk. We now know strong evidence that beside BMD, bone microarchitecture, one of the most important elements of bone quality, is a key factor in determining fracture risk. Recently, two new methods (spinal deformity index and trabecular bone score) have been shown to be useful markers of bone microarchitecture in GIO. Investigations of GIO in endogenous Cushing's syndrome have also contributed to our understanding on its natural history and reversibility. Relying on recently published guidelines for management of exogenous GIO, a short list of suggestions is provided regarding the optimal diagnostic and therapeutic approach to patients with endogenous GIO.

Thioredoxin interacting protein is a potential regulator of glucose and energy homeostasis in endogenous Cushing's syndrome

Recent studies have described bone as an endocrine organ regulating glucose metabolism, with insulin signaling regulating osteocalcin secretion and osteocalcin regulating β cell function. We have previously demonstrated increased bone expression of TXNIP in patients with endogenous Cushing's syndrome (CS), and we hypothesized that TXNIP could contribute to the dysregulated glucose metabolism in CS. We studied 33 CS patients and 29 matched controls, with bone biopsies from nine patients, before and after surgical treatment. In vitro, the effect of silencing TXNIP (siTXNIP) in osteoblasts, including its effect on human islet cells, was examined. Our major findings were: (i) The high mRNA levels of TXNIP in bone from CS patients were significantly associated with high levels of glucose and insulin, increased insulin resistance, and decreased insulin sensitivity in these patients. (ii) Silencing TXNIP in osteoblasts enhanced their OC response to insulin and glucose and down-regulated interleukin (IL)-8 levels in these cells. (iii) Conditional media from siTXNIP-treated osteoblasts promoted insulin content and anti-inflammatory responses in human islet cells. We recently demonstrated that the thioredoxin/TXNIP axis may mediate some detrimental effects of glucocorticoid excess on bone tissue in CS. Here we show that alterations in this axis also may affect glucose metabolism in these patients.

The role of salivary cortisol measured by liquid chromatography-tandem mass spectrometry in the diagnosis of subclinical hypercortisolism

OBJECTIVE

The use of late-night salivary cortisol (LNSalC) for diagnosing subclinical hypercortisolism (SH) is debated. No data are available regarding the role of LNSalC as measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in SH diagnosis. The aim of this study was to evaluate the diagnostic accuracy of LNSalC measured by LC-MS/MS in SH.

DESIGN

Cross-sectional prospective study of outpatients.

METHODS

In 70 consecutive patients with adrenal incidentalomas (AI), without signs and symptoms of hypercortisolism, we diagnosed SH in the presence of at least two of the following: cortisol after 1 mg overnight dexamethasone suppression test (1  mg DST) >83  nmol/l, 24-h urinary free cortisol (UFC) >193  nmol/24  h, and morning ACTH <2.2  pmol/l. The LNSalC levels by LC-MS/MS at 2300  h (normal values <2.8  nmol/l) and the presence of hypertension, type 2 diabetes mellitus (T2DM), and osteoporosis (OP) were assessed.

RESULTS

The increased LNSalC levels (>2.8  nmol/l) had an 83.3% specificity (SP) and a 31.3% sensitivity (SN) for predicting the biochemical diagnosis of SH. The increased LNSalC had an 85.2% SP and a 55.6% SN for predicting the presence of hypertension, T2DM, and OP, while the combination of LNSalC >1.4  nmol/l (cutoff with 100% SN) plus 1 mg DST >50  nmol/l had an 88.9% SN and an 85.2% SP (similar to SH criterion at enrollment).

CONCLUSIONS

In AI patients, LNSalC measured by LC-MS/MS appears to be useful in combination with 1 mg DST for diagnosing SH, while it is not useful as a single criterion.

Diagnostic performance of late-night salivary cortisol measured by automated electrochemiluminescence immunoassay in obese and overweight patients referred to exclude Cushing's syndrome

This study estimates diagnostic performance of late-night salivary cortisol (LNSC) as measured by automated electrochemiluminescence immunoassay (ECLIA), evaluates the clinical implication of two consecutive LNSC measurements, and compares its accuracy with enzyme-linked immunosorbent assay (ELISA) and serum cortisol after low-dose dexamethasone suppression test (DST) in obese and overweight patients referred for suspected Cushing's syndrome (CS). One hundred twenty three consecutive obese and overweight referred patients and 98 healthy volunteers provided two saliva samples collected at 23:00 using a Salivette (Sarstedt, Germany), assayed by ECLIA (Cobas e601) and ELISA. The patients underwent DST and were further evaluated until CS was pathologically confirmed (n = 45) or excluded. Diagnostic performance of LNSC was evaluated by receiver operating characteristic (ROC) analysis. The total areas under the curve (AUC) were calculated to compare the different tests. We found that a cut-off value of 9.4 nmol/l can differentiate CS among obese and overweight patients with sensitivity of 84.4 % (95% CI 71.2-92.2), specificity of 92.3 % (95% CI 84.2-96.4), and diagnostic odds ratio of 65.1 (95% CI 20.4-207.6). No difference was found between AUCs from the first, second, and the mean from the two LNSC measurements (ECLIA), LNSC (ELISA), or DST. The single LNSC (ECLIA) and DST improved the sensitivity and specificity for concordant results up to 100 and 97.4 %, respectively. In conclusion, due to its automation and its comparable diagnostic performance, ECLIA is preferable as a first-line LNSC screening test for CS. The initial use of single LNSC followed by DST provides better diagnostic performance for concordant results.

Cushing's syndrome: diagnosis and surveillance using salivary cortisol

This short review summarizes the use of late-night salivary cortisol measurement in the diagnosis of Cushing's syndrome, in the evaluation of patients with adrenal incidentalomas, and in monitoring of post-operative patients, with a focus on the different assay methodologies currently in common use. The focus is on recent studies identified by literature searches using Ovid Medline and Google Scholar as well as analysis of several recent review articles on the topic. Measurement of late night salivary cortisol (LNSC) has an excellent sensitivity and specificity for the diagnosis of Cushing's syndrome regardless of the assay methodology used. Immunoassays have the advantage of simplicity, low cost, and small sample volume requirement, while liquid chromatography-tandem mass spectrometry has the advantage of a high specificity for cortisol and the ability to measure cortisone. The overnight dexamethasone suppression test appears to be superior to LNSC measurement in the evaluation of patients with adrenal incidentalomas. LNSC measurement is an excellent approach to monitor post-operative Cushing's disease patients for surgical failure or recurrence. Salivary cortisol is most useful as the initial test when Cushing's syndrome is suspected and for periodic patient monitoring after pituitary surgery for Cushing's disease.

Subclinical Cushing's syndrome: definition and management

Subclinical Cushing's syndrome is an ill-defined endocrine disorder that may be observed in patients bearing an incidentally found adrenal adenoma. The concept of subclinical Cushing's syndrome stands on the presence of ACTH-independent cortisol secretion by an adrenal adenoma, that is not fully restrained by pituitary feed-back. A hypercortisolemic state of usually minimal intensity may ensue and eventually cause harm to the patients in terms of metabolic and vascular diseases, and bone fractures. However, the natural history of subclinical Cushing's syndrome remains largely unknown. The present review illustrates the currently used methods to ascertain the presence of subclinical Cushing's syndrome and the surrounding controversy. The management of subclinical Cushing's syndrome, that remains a highly debated issue, is also addressed and discussed. Most of the recommendations made in this chapter reflects the view and the clinical experience of the Authors and are not based on solid evidence.

Evaluation of salivary cortisol measurements for the diagnosis of subclinical Cushing's syndrome

Late-night salivary cortisol (NSC) has been recognized as a sensitive and easy-to-perform screening test for the diagnosis of overt Cushing's syndrome (CS). However, there have been few reports on the diagnostic utility of salivary cortisol (SC) measurement in the diagnosis of subclinical Cushing's syndrome (SCS). Therefore, the present study was designed to evaluate the usefulness of SC measurements at late-night and after overnight 1 mg dexamethasone suppression test (DST) for the diagnosis of SCS in 42 patients with adrenal incidentaloma. We evaluated 16 patients with SCS, 12 with nonfunctioning adenoma (NFA), 8 with primary aldosteronism (PA), and 6 with pheochromocytoma (Pheo). NSC levels in SCS patients (0.238 ± 0.106 µg/dL) were significantly (P < 0.05) higher than those in NFA patients (0.154 ± 0.104 µg/dL); the cutoff value (0.11 µg/dL) by ROC analysis gave high sensitivity (100%) with low specificity (50%). Post DST SC levels in SCS patients (0.238 ± 0.116 µg/dL) were significantly (P = 0.0081) higher than those in NFA patients (0.136 ± 0.110 µg/dL); the cutoff value (0.12 µg/dL) by ROC analysis gave high sensitivity (93.8%) with somewhat improved specificity (58.3%). Both NSC and post DST SC levels were comparable between NFA, PA, and Pheo patients. In conclusion, our study revealed that measurements of NSC and/or post DST SC among patients with adrenal incidentaloma prove to have high sensitivities, but low specificities for the diagnosis of SCS from NFA, suggesting its possible alternative option before the screening tests for SCS currently employed in Japan.

Challenges and benefits of endogenous steroid analysis by LC–MS/MS

Quantification of endogenous hormonal steroids and their precursors is essential for diagnosing a wide range of endocrine disorders. Historically, these analyses have been carried out using immunoassay, but such methods are problematic, especially for low-concentration analytes, due to assay interference by other endogenous steroids. MS offers improved specificity over immunoassay and can be highly sensitive. GC–MS, with use of stable isotopically labeled internal standards, is considered the ‘gold standard’ method for serum steroid analysis. GC–MS is the method of choice for profiling steroid metabolites in urine, but these techniques are not appropriate for routine use in clinical laboratories owing to a need for extensive sample preparation, as well as analytical expertise. LC–MS/MS compares well to GC–MS in terms of accuracy, precision and sensitivity, but allows simplified sample preparation. While most publications have featured only one or a limited number of steroids, we consider that steroid paneling (which we propose as the preferred term for multitargeted steroid analysis) has great potential to enable clinicians to make a definitive diagnosis. It is adaptable for use in a number of matrices, including serum, saliva and dried blood spots. However, LC–MS/MS-based steroid analysis is not straightforward, and understanding the chemical and analytical processes involved is essential for implementation of a robust clinical service. This article discusses specific challenges in the measurement of endogenous steroids using LC–MS/MS, and provides examples of the benefits it offers.

Clinical review: Diagnosis and treatment of subclinical hypercortisolism

CONTEXT

Subclinical hypercortisolism (SH) is a condition of biochemical cortisol excess without the classical signs or symptoms of overt hypercortisolism. It is thought to be present in the 5-30% of patients with incidentally discovered adrenal mass (adrenal incidentalomas), which in turn are found in 4-7% of the adult population. Therefore, SH has been suggested to be present in 0.2-2.0% of the adult population. Some studies suggested that this condition is present in 1-10% of patients with diabetes or established osteoporosis. The present manuscript reviews the literature on diagnostic procedures and the metabolic effect of the recovery from SH.

EVIDENCE ACQUISITION

A PubMed search was used to identify the available studies. The most relevant studies from 1992 to November 2010 have been included in the review.

EVIDENCE SYNTHESIS

The available data suggest that SH may be associated with chronic complications, such as hypertension, diabetes mellitus, overweight/obesity, and osteoporosis. The available intervention studies suggest that the recovery from SH may lead to the improvement of hypertension and diabetes mellitus. A retrospective study suggests that this beneficial effect could be predicted before surgery.

CONCLUSIONS

SH is suggested to be associated with some chronic complications of overt cortisol excess. Recovery from this condition seems to improve these complications. However, a large, prospective, randomized study is needed to confirm this hypothesis and to establish the best diagnostic approach to identify patients with adrenal incidentalomas who can benefit from surgery.