Cosyntropin-Stimulated Serum Free Cortisol in Healthy, Adrenally Insufficient, and Mildly Cirrhotic Populations

European Society of Endocrinology and Endocrine Society Joint Clinical Guideline: Diagnosis and Therapy of Glucocorticoid-induced Adrenal Insufficiency

Glucocorticoids are widely prescribed as anti-inflammatory and immunosuppressive agents. This results in at least 1% of the population using chronic glucocorticoid therapy, being at risk for glucocorticoid-induced adrenal insufficiency. This risk is dependent on the dose, duration and potency of the glucocorticoid, route of administration, and individual susceptibility. Once glucocorticoid-induced adrenal insufficiency develops or is suspected, it necessitates careful education and management of affected patients. Tapering glucocorticoids can be challenging when symptoms of glucocorticoid withdrawal develop, which overlap with those of adrenal insufficiency. In general, tapering of glucocorticoids can be more rapidly within a supraphysiological range, followed by a slower taper when on physiological glucocorticoid dosing. The degree and persistence of HPA axis suppression after cessation of glucocorticoid therapy are dependent on overall exposure and recovery of adrenal function varies greatly amongst individuals. This first European Society of Endocrinology/Endocrine Society joint clinical practice guideline provides guidance on this clinically relevant condition to aid clinicians involved in the care of patients on chronic glucocorticoid therapy.

European Society of Endocrinology and Endocrine Society Joint Clinical Guideline: Diagnosis and therapy of glucocorticoid-induced adrenal insufficiency

Glucocorticoids are widely prescribed as anti-inflammatory and immunosuppressive agents. This results in at least 1% of the population using chronic glucocorticoid therapy, being at risk for glucocorticoid-induced adrenal insufficiency. This risk is dependent on the dose, duration and potency of the glucocorticoid, route of administration, and individual susceptibility. Once glucocorticoid-induced adrenal insufficiency develops or is suspected, it necessitates careful education and management of affected patients. Tapering glucocorticoids can be challenging when symptoms of glucocorticoid withdrawal develop, which overlap with those of adrenal insufficiency. In general, tapering of glucocorticoids can be more rapidly within a supraphysiological range, followed by a slower taper when on physiological glucocorticoid dosing. The degree and persistence of HPA axis suppression after cessation of glucocorticoid therapy are dependent on overall exposure and recovery of adrenal function varies greatly amongst individuals. This first European Society of Endocrinology/Endocrine Society joint clinical practice guideline provides guidance on this clinically relevant condition to aid clinicians involved in the care of patients on chronic glucocorticoid therapy.

Salivary Cortisol Response to ACTH Stimulation Is a Reliable Alternative to Serum Cortisol in Evaluating Hypoadrenalism

CONTEXT

The serum total cortisol response to the ACTH stimulation test is widely used to assess adrenocortical function but is affected by changes in cortisol-binding globulin (CBG) concentration. Salivary cortisol reflects free cortisol concentrations and may offer a reliable alternative.

OBJECTIVES

(1) To establish the salivary cortisol response to ACTH stimulation in healthy volunteers and patients with altered CBG concentrations; (2) to evaluate the performance of a lower reference limit (LRL) determined in healthy volunteers in patients with suspected hypoadrenalism (SH-patients).

DESIGN

A 250 µg ACTH stimulation test was undertaken in 139 healthy volunteers, 24 women taking an estradiol-containing oral contraceptive pill (OCP-females), 10 patients with low serum protein concentration (LP-patients), and 30 SH-patients. Salivary cortisol was measured by liquid chromatography-tandem mass spectrometry. Mean and LRL of the 30-minute salivary cortisol response (mean-1.96 standard deviation) were derived from log-transformed concentrations. The LRL was applied as a diagnostic cut-off in SH-patients, with comparison to the serum response.

RESULTS

Mean CBG concentrations (range) were 58 (42-81) mg/L, 64 (43-95) mg/L, 41 (28-60) mg/L, and 116 (84-159) mg/L in males, females, LP-patients, and OCP-females, respectively. The mean 30-minute salivary cortisol concentration was 19.3 (2.5th-97.5th percentile 10.3-36.2) nmol/L in healthy volunteers. Corresponding values were not different in OCP-females [19.7 (9.5-41.2) nmol/L; P = .59] or LP-patients [19.0 (7.7-46.9) nmol/L; P = .97]. Overall diagnostic agreement between salivary and serum responses in SH-patients was 79%.

CONCLUSION

Salivary cortisol response to ACTH stimulation offers a reliable alternative to serum and may be especially useful in conditions of altered CBG concentration.

Glucocorticoid induced adrenal insufficiency

Synthetic glucocorticoids are widely used for their anti-inflammatory and immunosuppressive actions. A possible unwanted effect of glucocorticoid treatment is suppression of the hypothalamic-pituitary-adrenal axis, which can lead to adrenal insufficiency. Factors affecting the risk of glucocorticoid induced adrenal insufficiency (GI-AI) include the duration of glucocorticoid therapy, mode of administration, glucocorticoid dose and potency, concomitant drugs that interfere with glucocorticoid metabolism, and individual susceptibility. Patients with exogenous glucocorticoid use may develop features of Cushing's syndrome and, subsequently, glucocorticoid withdrawal syndrome when the treatment is tapered down. Symptoms of glucocorticoid withdrawal can overlap with those of the underlying disorder, as well as of GI-AI. A careful approach to the glucocorticoid taper and appropriate patient counseling are needed to assure a successful taper. Glucocorticoid therapy should not be completely stopped until recovery of adrenal function is achieved. In this review, we discuss the factors affecting the risk of GI-AI, propose a regimen for the glucocorticoid taper, and make suggestions for assessment of adrenal function recovery. We also describe current gaps in the management of patients with GI-AI and make suggestions for an approach to the glucocorticoid withdrawal syndrome, chronic management of glucocorticoid therapy, and education on GI-AI for patients and providers.

Investigation of the Hypothalamo-pituitary-adrenal (HPA) axis: a contemporary synthesis

The hypothalamo-pituitary-adrenal (HPA) axis is one of the main components of the stress system. Maintenance of normal physiological events, which include stress responses to internal or external stimuli in the body, depends on appropriate HPA axis function. In the case of severe cortisol deficiency, especially when there is a triggering factor, the patient may develop a life-threatening adrenal crisis which may result in death unless early diagnosis and adequate treatment are carried out. The maintenance of normal physiology and survival depend upon a sufficient level of cortisol in the circulation. Life-long glucocorticoid replacement therapy, in most cases meeting but not exceeding the need of the patient, is essential for normal life expectancy and maintenance of the quality of life. To enable this, the initial step should be the correct diagnosis of adrenal insufficiency (AI) which requires careful evaluation of the HPA axis, a highly dynamic endocrine system. The diagnosis of AI in patients with frank manifestations is not challenging. These patients do not need dynamic tests, and basal cortisol is usually enough to give a correct diagnosis. However, most cases of secondary adrenal insufficiency (SAI) take place in a gray zone when clinical manifestations are mild. In this situation, more complicated methods that can simulate the response of the HPA axis to a major stress are required. Numerous studies in the assessment of HPA axis have been published in the world literature. In this review, the tests used in the diagnosis of secondary AI or in the investigation of suspected HPA axis insufficiency are discussed in detail, and in the light of this, various recommendations are made.

Salivary cortisol levels by tandem mass spectrometry during high dose ACTH stimulation test for adrenal insufficiency in children

PURPOSE

Serum cortisol measurements after ACTH stimulation are currently used to evaluate for adrenal insufficiency in children. We aim to determine if salivary cortisol measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) can confirm or replace serum cortisol during high dose ACTH stimulation test to improve test compliance and interpretation. We also aim to gain preliminary understanding of normal ranges of salivary cortisol in normal children at am, bedtime, and midnight.

METHODS

Children aged 6-17 years meeting study criteria and tested for adrenal insufficiency were recruited to concomitantly collect saliva and serum samples during high dose ACTH stimulation test. Normal children aged 3-18 years were recruited to collect morning, bedtime, and midnight saliva samples. Salivary cortisol was measured using LC-MS/MS while serum cortisol was determined by an immunoassay.

RESULTS

Salivary cortisol in normal children were higher at am and lower at bedtime and midnight (p value <0.0002 and <0.007, respectively). The midnight and bedtime levels were not sufficiently different (p value 0.36). Salivary cortisol during ACTH stimulation test positively and closely correlated with serum cortisol with 100% specificity and sensitivity when 18 µg/dL for serum and 500 ng/dL for salivary cortisol were used as cutoff values respectively for adrenal sufficiency.

CONCLUSIONS

Measurement of salivary cortisol by LC-MS/MS is less invasive, more convenient and better time controlled in busy pediatric clinic, therefore is better suited for young children to be used during high dose ACTH stimulation test to evaluate for adrenal insufficiency and to assist interpretation of test results by serum cortisol.

Plasma Free Cortisol in States of Normal and Altered Binding Globulins: Implications for Adrenal Insufficiency Diagnosis

CONTEXT

Accurate diagnosis of adrenal insufficiency is critical because there are risks associated with overdiagnosis and underdiagnosis. Data using liquid chromatography tandem mass spectrometry (LC/MS/MS) free cortisol (FC) assays in states of high or low cortisol-binding globulin (CBG) levels, including cirrhosis, critical illness, and oral estrogen use, are needed.

DESIGN

Cross-sectional.

OBJECTIVE

Determine the relationship between CBG and albumin as well as total cortisol (TC) and FC in states of normal and abnormal CBG. Establish the FC level by LC/MS/MS that best predicts TC of <18 μg/dL (497 nmol/L) (standard adrenal insufficiency diagnostic cutoff) in healthy individuals.

SUBJECTS

This study included a total of 338 subjects in four groups: healthy control (HC) subjects (n = 243), patients with cirrhosis (n = 38), intensive care unit patients (ICU) (n = 26), and oral contraceptive (OCP) users (n = 31).

MAIN OUTCOME MEASURE(S)

FC and TC by LC/MS/MS, albumin by spectrophotometry, and CBG by ELISA.

RESULTS

TC correlated with FC in the ICU (R = 0.91), HC (R = 0.90), cirrhosis (R = 0.86), and OCP (R = 0.70) groups (all P < 0.0001). In receiver operator curve analysis in the HC group, FC of 0.9 μg/dL (24.8 nmol/L) predicted TC of <18 μg/dL (497 nmol/L; 98% sensitivity, 91% specificity; AUC, 0.98; P < 0.0001). Decreasing the cutoff to 0.7 μg/dL led to a small decrease in sensitivity (92%) with similar specificity (91%).

CONCLUSIONS

A cutoff FC of <0.9 μg/dL (25 nmol/L) in this LC/MS/MS assay predicts TC of <18 μg/dL (497 nmol/L) with excellent sensitivity and specificity. This FC cutoff may be helpful in ruling out adrenal insufficiency in patients with binding globulin derangements.

Liver and Steroid Hormones-Can a Touch of p53 Make a Difference?

The liver is the main metabolic organ in the body, serving as a significant hormonal secretory gland and functioning to maintain hormone balance and homeostasis. Steroid hormones regulate various biological pathways, mainly in the reproductive system and in many metabolic processes. The liver, as well as steroid hormones, contribute significantly, through functional intertwine, to homeostasis maintenance, and proper responses during stress. Malfunction of either has a significant impact on the other and may lead to severe liver diseases as well as to several endocrine syndromes. Thus, the regulation on liver functions as on steroid hormones levels and activities is well-controlled. p53, the well-known tumor suppressor gene, was recently found to regulate metabolism and general homeostasis processes, particularly within the liver. Moreover, p53 was shown to be involved in steroid hormones regulation. In this review, we discuss the bi-directional regulation of the liver and the steroid hormones pointing to p53 as a novel regulator in this axis. A comprehensive understanding of the molecular mechanisms of this axis may help to prevent and treat related disease, especially with the increasing exposure of the population to environmental steroid hormones and steroid hormone-based medication.

Pitfalls in the interpretation of the cosyntropin stimulation test for the diagnosis of adrenal insufficiency

PURPOSE OF REVIEW

Adrenal insufficiency is a rare disease characterized by cortisol deficiency. The evaluation of patients suspected of having adrenal insufficiency can be challenging because of the rarity of the disease and limitations in the biochemical assessment of the cortisol status by either basal or dynamic testing [adrenocorticotropic hormone (ACTH) stimulation test]. Prompt and adequate diagnosis is of paramount importance to avoid adverse outcomes. We aimed to summarize the recent developments in the conduction and interpretation of the ACTH stimulation test for the diagnosis of adrenal insufficiency.

RECENT FINDINGS

The ACTH stimulation test is commonly performed in patients suspected of having adrenal insufficiency when the basal serum cortisol levels are inconclusive. Recent literature has evaluated the impact of technical aspects such as time of the day the test is performed, type of assay and sample source used for cortisol measurement on the clinical value of this test, as well as the feasibility of reliable low dose ACTH testing.

SUMMARY

Clinicians evaluating patients with suspected adrenal insufficiency should take into consideration the clinical presentation (likelihood of adrenal insufficiency before testing) when interpreting the results of the ACTH stimulation test and be aware of clinical and technical factors that can affect cortisol values and diagnostic accuracy of this test.

Salivary Cortisol Determination in ACTH Stimulation Test to Diagnose Adrenal Insufficiency in Patients with Liver Cirrhosis

PURPOSE

The prevalence of adrenal insufficiency (AI) in patients with decompensated liver cirrhosis is unknown. Because these patients have lower levels of cortisol-binding carrier proteins, their total serum cortisol (TSC) correlates poorly with free serum cortisol (FC). Salivary cortisol (SaC) correlates better with FC. We aimed to establish SaC thresholds for AI for the 250 μg intravenous ACTH test and to estimate the prevalence of AI in noncritically ill cirrhotic patients.

METHODS

We included 39 patients with decompensated cirrhosis, 39 patients with known AI, and 45 healthy volunteers. After subjects fasted ≥8 hours, serum and saliva samples were collected for determinations of TSC and SaC at baseline 0'(T₀) and at 30-minute intervals after intravenous administration of 250 μg ACTH [30'(T₃₀), 60'(T₆₀), and 90'(T₉₀)].

RESULTS

Based on the findings in healthy subjects and patients with known AI, we defined AI in cirrhotic patients as SaC-T₀< 0.08 μg/dL (2.2 nmol/L), SaC-T₆₀ < 1.43 μg/dl (39.5 nmol/L), or ΔSaC<1 μg/dl (27.6 nmol/L). We compared AI determination in cirrhotic patients with the ACTH test using these SaC thresholds versus established TSC thresholds (TSC-T₀< 9 μg/dl [248 nmol/L], TSC-T₆₀ < 18 μg/dl [497 nmol/L], or ΔTSC<9 μg/dl [248 nmol/L]). SaC correlated well with TSC. The prevalence of AI in cirrhotic patients was higher when determined by TSC (48.7%) than by SaC (30.8%); however, this difference did not reach statistical significance. AI was associated with sex, cirrhosis etiology, and Child-Pugh classification.

CONCLUSIONS

Measuring SaC was more accurate than TSC in the ACTH stimulation test. Measuring TSC overestimated the prevalence of AI in noncritically ill cirrhotic patients.

Serum Cortisol Levels via Radioimmunoassay vs Liquid Chromatography Mass Spectrophotometry in Healthy Control Subjects and Patients With Adrenal Incidentalomas

Background

Adrenal incidentalomas (AIs) are present in 4% of adults. As many as 30% may secrete cortisol autonomously in the absence of specific signs of overt hypercortisolism, in a phenomenon called subclinical hypercortisolism (SH). Diagnosis of SH is established by serum cortisol resistance to dexamethasone suppression.

Methods

We compared serum cortisol concentrations, as determined by radioimmunoassay (RIA) and liquid chromatography/tandem mass spectronomy (LC/MS-MS), in 73 patients with AI group (52 with unilateral AI) and 34 control subjects in 3 scenarios: basal; after 1-mg dexamethasone suppression; and after 0.25-mg stimulation with cosyntropin, a synthetic derivative of adrenocorticotropic hormone (ACTH). To bolster evidence for the diagnosis of SH, we also measured salivary cortisol levels at 11 PM and after DST, as well as plasma ACTH and serum dehydroepiandrosterone sulfate (DHEA-S) levels.

Results

We observed significant positive correlation (r = 0.9345, P <.001) for all 318 pairs of serum cortisol values, as measured by both methods.

Conclusions

Serum cortisol concentrations in patients with AI and in control subjects were very similar, as measured by RIA and LC/MS-MS.

SERUM FREE CORTISOL DURING GLUCAGON STIMULATION TEST IN HEALTHY SHORT-STATURED CHILDREN AND ADOLESCENTS

OBJECTIVE

The total cortisol (TC) response may be measured during the glucagon stimulation test (GST) for growth hormone (GH) reserve in order to assess the integrity of the hypothalamic-pituitary-adrenal (HPA) axis. Measurements of TC are unreliable in conditions of albumin and cortisol-binding globulin (CBG) alterations (e.g., hypoproteinemia or CBG deficiency). We aimed to measure the serum free cortisol (sFC) response to the GST in children and adolescents and determine whether it could predict the GH response to glucagon stimulation.

METHODS

Infants and children with either short stature or growth attenuation who were referred for evaluation of GH reserve underwent the GST.

RESULTS

The study population consisted of 103 subjects (62 females), median age 3.9 years (range, 0.5-14). The mean basal and peak TC levels were 13.3 ± 6.7 μg/dL and 29.6 ± 8.8 μg/dL, respectively. The mean basal and peak sFC levels were 0.7 ± 0.8 μg/dL and 1.7 ± 1.1 μg/dL, respectively. There was a negative correlation between peak TC and age ( r = -0.3, P = .007) but not between peak sFC and age ( r = -0.09, P = .36). Ninety-five percent of the patients had peak TC levels >15.8 μg/dL and peak sFC levels >0.6 μg/dL.

CONCLUSION

Our results on a cohort of healthy short-statured children can serve as reference values for the sFC response during GST. Based on these results, we propose peak TC levels >15.8 μg/dL and peak sFC levels >0.6 μg/dL for defining normalcy of the HPA axis during the GST in children and adolescents.

ABBREVIATIONS

ACTH = adrenocorticotrophic hormone BMI = body mass index CBG = cortisol-binding globulin GH = growth hormone GST = glucagon stimulation test HPA = hypothalamic-pituitary-adrenal SDS = standard deviation score sFC = serum free cortisol TC = total cortisol.

The role of corticosteroid-binding globulin in the evaluation of adrenal insufficiency

Cortisol is a hydrophobic molecule that is largely bound to corticosteroid-binding globulin (CBG) in the circulation. In the assessment of adrenal insufficiency, many clinicians measure a total serum cortisol level, which assumes that CBG is present in normal concentrations and with a normal binding affinity for cortisol. CBG concentration and affinity are affected by a number of common factors including oral contraceptive pills (OCPs), fever and infection, as well as rare mutations in the serine protease inhibitor A6 (SERPINA6) gene, and as such, total cortisol levels might not be the ideal way to assess adrenal function in all clinical circumstances. This paper reviews the limitations of immunoassay and liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the measurement of total cortisol, the challenges of measuring free serum cortisol directly as well as the difficulties in calculating an estimated free cortisol from total cortisol, CBG and albumin concentrations. Newer approaches to the evaluation of adrenal insufficiency, including the measurement of cortisol and cortisone in the saliva, are discussed and a possible future role for these tests is proposed.

Salivary cortisol and cortisone in the clinical setting

PURPOSE OF REVIEW

A resurgence of interest in salivary biomarkers has generated evidence for their value in assessing adrenal function. The advantages of salivary measurements include only free hormone is detected, samples can be collected during normal daily routines and stress-induced cortisol release is less likely to occur than during venepuncture. We review the use of salivary biomarkers to diagnose and monitor patients for conditions of cortisol excess and deficiency and discuss the value of measuring salivary cortisone versus salivary cortisol.

RECENT FINDINGS

Developments in laboratory techniques have enabled the measurement of salivary hormones with a high level of sensitivity and specificity. In states of altered cortisol binding, salivary biomarkers are more accurate measures of adrenal reserve than serum cortisol. Salivary cortisone is a superior marker of serum cortisol compared with salivary cortisol, specifically when serum cortisol is low and during hydrocortisone therapy when contamination of saliva may result in misleading salivary cortisol concentrations.

SUMMARY

Salivary cortisol and cortisone can be used to assess cortisol excess, deficiency and hydrocortisone replacement, with salivary cortisone having the advantage of detection when serum cortisol levels are low and there is no interference from oral hydrocortisone.

Establishing Normal Ranges of Basal and ACTH-Stimulated Serum Free Cortisol in Children

BACKGROUND

Normative data have been established for stimulated serum total cortisol in children but not for serum free cortisol.

METHODS

Children who were referred for ACTH testing to rule out adrenal insufficiency were enrolled. Only children with normal response and normal androgen levels were included. Total cortisol was determined by a chemiluminescence method, and free cortisol was measured by the same method following equilibrium dialysis.

RESULTS

The study group consisted of 85 subjects (28 male; 57 female) with a median age of 8.5 years (range 0.6-17.7). The mean basal and peak total cortisol levels were 11.5 ± 5.7 and 32.9 ± 6.2 μg/dl, respectively. The mean basal and peak free cortisol levels were 0.4 ± 0.3 and 1.8 ± 0.6 μg/dl, respectively. There was a negative correlation between peak total cortisol and age but not between peak free cortisol and age. The 3rd and 97th percentile values for peak free cortisol were 0.94 μg/dl (26 nmol/l) and 2.97 μg/dl (82 nmol/l), respectively.

CONCLUSIONS

Measurement of free cortisol has the advantage of being independent of cortisol-binding globulin levels. This study provides reference ranges for stimulated free cortisol in children, with a cutoff value of 0.9 μg/dl (25 nmol/l) as a normal response to a standard ACTH test.