Neutrophil-Lymphocyte Ratio as an Initial Screening Biomarker for Differential Diagnosis of Cushing’s Syndrome from Nonfunctional Adenoma in Patients with an Adrenal Mass

Objective. Assessing excess adrenal hormones is important in patients with adrenal mass. Current screening tests for excess cortisol hormones are complex, so it cannot be done sometimes due to the limited medical resources. The aim of the study was to evaluate whether the neutrophil-lymphocyte ratio (NLR) can be used as an initial screening biomarker for Cushing’s syndrome (CS) in patients with an adrenal mass. Methods. This retrospective study included a total of 185 patients with CS and 185 patients with nonfunctional adrenal adenoma (matched 1 : 1 by sex, body mass index, and discharge date). The NLR was compared between the two groups. The association between NLR and serum and urinary cortisol concentrations was analyzed, and an NLR cut-off value for CS screening was calculated. Results. NLR (3.38 (2.33, 5.45) vs. 2.13 (1.74, 3.00), P < 0.001 ) was significantly higher in the CS group than in the nonfunctional adenoma group. In CS patients, the NLR was positively associated with serum cortisol concentrations at 8 am, with 24-hour urine free cortisol and with serum cortisol after a 1 mg dexamethasone suppression test ( P < 0.001 each). An NLR cut-off of 2.2 had a sensitivity of 80.0% and a specificity of 54.05%. The weighted Youden index for the NLR was similar to that of the 24-hour urine free cortisol and late-night serum cortisol tests, which are recommended initial tests for CS diagnosis. Conclusion. The NLR may be useful for initial screening for CS among patients with an adrenal mass as an easy and convenient marker.

Diagnostic testing of autonomous cortisol secretion in adrenal incidentalomas

Objective: Autonomous cortisol secretion (ACS) is a condition with ACTH-independent cortisol overproduction from adrenal incidentalomas (AI) or adrenal hyperplasia. The hypercortisolism is often mild, and most patients lack typical clinical features of overt Cushing’s syndrome (CS). ACS is not well defined and diagnostic tests lack validation. Methods: Retrospective study of 165 patients with AI evaluated clinically and by assay of morning plasma ACTH, late-night saliva cortisol, serum DHEA sulphate (DHEAS), 24-h urine-free cortisol, and cortisol after dexamethasone suppression. Results: Patients with AI (n = 165) were diagnosed as non-functioning incidentalomas (NFI) (n = 82) or ACS (n = 83) according to current European guidelines. Late-night saliva cortisol discriminated poorly between NFI and ACS, showing a high rate of false-positive (23/63) and false-negative (38/69) results. The conventional low-dose dexamethasone suppression test (LDDST) did not improve the diagnostic specificity, compared with the 1 mg overnight DST. Receiver operating characteristic curve analysis of DHEAS in the two cohorts demonstrated an area under the curve of 0.76 (P < 0.01) with a sensitivity for ACS of 58% and a specificity of 80% using the recommended cutoff at 1.04 µmol/L (40 µg/dL). Conclusion: We here demonstrate in a large retrospective cohort of incidentaloma patients, that neither DHEAS, late-night saliva cortisol nor 24-h urine free cortisol are useful to discriminate between non-functioning adrenal incidentalomas and ACS. The conventional LDDST do not add further information compared with the 1 mg overnight DST. Alternative biomarkers are needed to improve the diagnostic workup of ACS.

SUN-LB34 A Case of BMAH With Aberrant Vasopressin Adrenal Receptors

We report on a 42 - year old woman was referred following an incidental finding of bilateral macronodular (nodules &gt; 1cm) adrenal glands after a computed tomography scan for investigation of an unrelated urological problem. Clear features of Cushing’s syndrome were elicited on initial clincal evaluation and screening tests confirmed the diagnosis biochemically: midnight salivary cortisol 15.4nmol/L (0.2 - 3nmol/L), 24 hour urine free cortisol &gt; 662.4nmol/L (8.3 - 118.7nmol/L per 24 hours) and an 8am serum cortisol measured 951nmol/L following 1mg dexamethasone suppression test (&lt; 50nm/L). A serum adrenocorticotropic hormone (ACTH) measured 0.3pmol/L (1.6 - 13.9pmol/L) suggesting, in light of the CT findings, an adrenal source of the elevated cortisol. Screening for aberrant adrenal receptors to catecholamines, Gastric inhibitory peptide, ACTH, vasopressin and Gonadotropin releasing hormone was performed. A positive biochemical response to ACTH and vasopressin was noted as measured serum cortisol increased to 1600pmol/L (upper limit of the assay). Following a unilateral adrenalectomy, were pathological examination of the respected adrenal gland confirmed adrenal hyperplasia, the patient had both clinical and biochemical resolution of hypercortisolemia. 2 weeks following surgery her midnight salivary cortisol measured 2.1nmol/L (0.2 - 3nmol/L) and 24 hour urine free cortisol 218nmol/L (8.3 - 118.7nmol/L per 24 hours). Her 8am ACTH also increased to 2.9pmol/L (1.6 - 13.9pmol/L). Biochemical screening of her sister showed no evidence of Cushing’s syndrome. Bilateral macronodualr hyperplasia (BMAH) represents a rare cause of Cushing’s syndrome may be diagnosed incidentally and is often associated with an insidious onset. We use this case to highlight the complexities of provocative testing for aberrant adrenal receptors which occur with BMAH and the utilization of unilateral adrenalectomy to achieve clinical and biochemical remission of Cushing’s syndrome thus, removing the need for post - operative steroid replacement following bilateral adrenalectomy.

A commentary on Diagnosing Cushing’s disease in the context of renal failure

The diagnosis of endogenous hypercortisolism (Cushing's syndrome) is extremely challenging. Chronic kidney disease (CKD) increases the activity of the hypothalamic-pituitary-adrenal axis making the diagnosis of Cushing's syndrome even more challenging. This is particularly so since urine free cortisol (UFC) testing is not useful in CKD. The case report by Stroud et al. in this issue of the European Journal of Endocrinology highlights this problem by finding normal UFC in a patient with pituitary ACTH-dependent Cushing's syndrome. Elevated late-night salivary cortisol (LNSC) testing was diagnostic and pituitary adenomectomy was curative. LNSC measurement is the diagnostic test of choice in patients with suspected Cushing's syndrome, particularly in the presence of CKD..

Higher urinary cortisol levels associate with increased cardiovascular risk

There are conflicting data on whether variations of physiologic cortisol levels associated with cardiovascular risk. We hypothesize that prior discordant findings are related to problems associated with varying sample size, techniques for assessing cardiovascular risk and failure to adequately account for environmental factors. To address these issues, we utilized a large sample size, selected the Framingham risk score to compute cardiovascular risk and performed the study in a highly controlled setting. We had two main objectives: determine whether higher, yet physiologic, cortisol levels associated with increased cardiovascular risk and determine whether caveolin-1 (rs926198) risk allele carriers associated with increased cardiovascular risk. This was a cross-sectional study of 574 non-diabetic individuals who completed a common protocol. Data collection included fasting blood samples, blood pressure measurements and a 24-h urine-free cortisol collection. Five hundred seventeen of these participants also completed caveolin-1 genotyping. Subjects were classified as belonging to either the low-mode or high-mode urine-free cortisol groups, based on the bimodal distribution of urine-free cortisol. In multivariate analysis, Framingham risk score was statistically higher in the high-mode cortisol group (10.22 (mean) ± 0.43 (s.e.m.)) compared to the low-mode cortisol group (7.73 ± 0.34), P < 0.001. Framingham risk score was also statistically higher in the caveolin-1 risk allele carriers (8.91 ± 0.37) compared to caveolin-1 non-risk allele carriers (7.59 ± 0.48), P = 0.034. Overall, the estimated effect on Framingham risk score of carrying the caveolin-1 risk allele was 1.33 ± 0.61, P = 0.029. Both urinary cortisol and caveolin-1 risk allele status are independent predictors of Framingham risk score.

Plasma Agouti-Related Protein and Cortisol Levels in Cushing Disease: Evidence for the Regulation of Agouti-Related Protein by Glucocorticoids in Humans

Context Glucocorticoids regulate energy balance, in part by stimulating the orexigenic neuropeptide agouti-related protein (AgRP). AgRP neurons express glucocorticoid receptors, and glucocorticoids have been shown to stimulate AgRP gene expression in rodents. Objective We sought to determine whether there is a relationship between plasma AgRP and hypothalamic AgRP in rats and to evaluate the relationship between cortisol and plasma AgRP in humans. Methods We retrospectively evaluated plasma AgRP levels prior to transsphenoidal surgery in 31 patients with Cushing disease (CD) vs 31 sex- and body mass index–matched controls from a separate study. We then prospectively measured plasma AgRP, before and 6 to 12 months after surgery, in a subgroup of 13 patients with CD. Plasma and hypothalamic AgRP were measured in adrenalectomized rats with and without corticosterone replacement. Results Plasma AgRP was stimulated by corticosterone in rats and correlated with hypothalamic AgRP expression. Plasma AgRP levels were higher in patients with CD than in controls (139 ± 12.3 vs 54.2 ± 3.1 pg/mL; P &lt; 0.0001). Among patients with CD, mean 24-hour urine free cortisol (UFC) levels were 257 ± 39 μg/24 hours. Strong positive correlations were observed between plasma AgRP and UFC (r = 0.76; P &lt; 0.0001). In 11 of 13 patients demonstrating surgical cure, AgRP decreased from 126 ± 20.6 to 62.5 ± 8.0 pg/mL (P &lt; 0.05) postoperatively, in parallel with a decline in UFC. Conclusions Plasma AgRP levels are elevated in CD, are tightly correlated with cortisol concentrations, and decline with surgical cure. These data support the regulation of AgRP by glucocorticoids in humans. AgRP’s role as a potential biomarker and as a mediator of the adverse metabolic consequences of CD deserves further study.