International survey on high- and low-dose synacthen test and assessment of accuracy in preparing low-dose synacthen

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.

Prediction of adrenal insufficiency after pituitary surgery: a retrospective study using beckman access cortisol assay

PURPOSE

Identifying patients requiring glucocorticoid replacement therapy after pituitary surgery is challenging as the tests commonly used for the diagnosis of secondary adrenal insufficiency (SAI) are not recommended in the immediate postoperative period. There are controversial data on the role of postoperative days' morning cortisol, with no specific data for each cortisol assay. The aim of this study is to investigate the reliability of 8.00 a.m. cortisol of the first and second postoperative days in predicting SAI.

METHODS

Data of patients underwent pituitary surgery in Humanitas Research Hospital in Italy, from March 2017 to August 2022, were retrospectively analyzed. Definitive diagnosis of SAI was made through ACTH test 1 µg six weeks after surgery. Cortisol was measured through Beckman Access Cortisol and the diagnosis of SAI was made if cortisol peak was below 14.8 µg/dL (408 nmol/L) at 30 or 60 min after stimulus.

RESULTS

Of the sixty-four patients enrolled, seven developed SAI. The ROC curves demonstrated that both first- and second-day postoperative 8.00 a.m. cortisol predict SAI (AUC 0.94 and 0.95, respectively). The optimal thresholds were 15.6 µg/dL (430.3 nmol/L; accuracy 89%) for the first day and 11.5 µg/dL (317.2 nmol/L, accuracy 81%) for the second day. Patients who developed SAI had larger tumors (p = 0.004) and lower fT4 (p = 0.038) before surgery.

CONCLUSIONS

Clinicians might rely on the first- and second- postoperative days 8.00 a.m. cortisol to identify patients to discharge with glucocorticoid replacement therapy waiting for the confirmation of SAI through the ACTH test.

Multivariable Model to Predict an ACTH Stimulation Test to Diagnose Adrenal Insufficiency Using Previous Test Results

Context

The adrenocorticotropin hormone stimulation test (AST) is used to diagnose adrenal insufficiency, and is often repeated in patients when monitoring recovery of the hypothalamo-pituitary-adrenal axis.

Objective

To develop and validate a prediction model that uses previous AST results with new baseline cortisol to predict the result of a new AST.

Methods

This was a retrospective, longitudinal cohort study in patients who had undergone at least 2 ASTs, using polynomial regression with backwards variable selection, at a Tertiary UK adult endocrinology center. Model was developed from 258 paired ASTs over 5 years in 175 adults (mean age 52.4 years, SD 16.4), then validated on data from 111 patients over 1 year (51.8, 17.5) from the same center, data collected after model development. Candidate prediction variables included previous test baseline adrenocorticotropin hormone (ACTH), previous test baseline and 30-minute cortisol, days between tests, and new baseline ACTH and cortisol used with calculated cortisol/ACTH ratios to assess 8 candidate predictors. The main outcome measure was a new test cortisol measured 30 minutes after Synacthen administration.

Results

Using 258 sequential ASTs from 175 patients for model development and 111 patient tests for model validation, previous baseline cortisol, previous 30-minute cortisol and new baseline cortisol were superior at predicting new 30-minute cortisol (R2 = 0.71 [0.49-0.93], area under the curve [AUC] = 0.97 [0.94-1.0]) than new baseline cortisol alone (R2 = 0.53 [0.22-0.84], AUC = 0.88 [0.81-0.95]).

Conclusion

Results of a previous AST can be objectively combined with new early-morning cortisol to predict the results of a new AST better than new early-morning cortisol alone. An online calculator is available at https://endocrinology.shinyapps.io/sheffield_sst_calculator/ for external validation.

COVID-19 pandemic and adrenals: deep insights and implications in patients with glucocorticoid disorders

PURPOSE

Coronavirus disease-19 (COVID-19) has spread throughout the world. It was initially defined as a potentially severe syndrome affecting the respiratory tract, but it has since been shown to be a systemic disease with relevant extrapulmonary manifestations that increase mortality. The endocrine system has been found to be vulnerable to COVID-19 infection. The current review aims to evaluate the available data on the impact of COVID-19 infection and treatment, as well as COVID-19 vaccines, on adrenal gland function, particularly in patients with GC disorders.

METHODS

A thorough search of published peer-reviewed studies in PubMed was performed using proper keywords.

RESULTS

Adrenal viral tropism and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication in the adrenal glands have been demonstrated, and adrenal insufficiency (AI) is a rare, but potentially severe complication in COVID-19 disease, whose recognition can be difficult if only for the empirical treatments administered in the early stages. Glucocorticoid (GC) treatment have had a pivotal role in preventing clinical deterioration in patients with COVID-19, but long-term GC use may increase COVID-19-related mortality and the development of iatrogenic AI. Patients with GC disorders, especially AI and Cushing's syndrome, have been identified as being at high risk of COVID-19 infection and complications. Published evidence suggests that AI patient awareness and proper education may help adjust GC replacement therapy appropriately when necessary, thereby reducing COVID-19 severity. The COVID-19 pandemic has had an impact on AI management, particularly in terms of adherence to patients' care plans and self-perceived challenges. On the other hand, published evidence suggests that the clinical course of COVID-19 may be affected by the severity of hypercortisolism in patients with CS. Therefore, to ameliorate the risk profile in these patients, cortisol levels should be adequately controlled, along with careful monitoring of metabolic and cardiovascular comorbidities. To date, the COVID-19 vaccine remains the only available tool to face SARS-CoV-2, and it should not be treated differently in patients with AI and CS.

CONCLUSION

SARS-CoV-2 infection has been linked to adrenal damage and AI is a rare complication in COVID-19 disease, requiring prompt recognition. Educational efforts and patient awareness may reduce COVID-19 severity in patients with AI. Control of cortisol levels and monitoring of complications may improve the clinical course of COVID-19 in patients with CS.

Diagnostic strategies in adrenal insufficiency

PURPOSE OF REVIEW

Adrenal insufficiency (AI) is the clinical manifestation of deficient production of glucocorticoids with occasionally deficiency also in mineralocorticoids and adrenal androgens and constitutes a fatal disorder if left untreated. The aim of this review is to summarize the new trends in diagnostic methods used for determining the presence of AI.

RECENT FINDINGS

Novel aetiologies of AI have emerged; severe acute respiratory syndrome coronavirus 2 infection was linked to increased frequency of primary AI (PAI). A new class of drugs, the immune checkpoint inhibitors (ICIs) widely used for the treatment of several malignancies, has been implicated mostly with secondary AI, but also with PAI. Salivary cortisol is considered a noninvasive and patient-friendly tool and has shown promising results in diagnosing AI, although the normal cut-off values remain an issue of debate depending on the technique used. Liquid chromatography-mass spectrometry (LC-MS/MS) is the most reliable technique although not widely available.

SUMMARY

Our research has shown that little progress has been made regarding our knowledge on AI. Coronavirus disease 2019 and ICIs use constitute new evidence on the pathogenesis of AI. The short synacthen test (SST) remains the 'gold-standard' method for confirmation of AI diagnosis, although salivary cortisol is a promising tool.

ACTH Stimulation Test for the Diagnosis of Secondary Adrenal Insufficiency: Light and Shadow

Secondary Adrenal Insufficiency (SAI) is a condition characterized by inappropriately low ACTH secretion due to a disease or injury to the hypothalamus or the pituitary. The evaluation when suspected is often challenging for the non-specific symptoms, the rarity of the disease, and the pitfalls associated with laboratory tests. A prompt and correct diagnosis of SAI is essential because although an adequate hormonal replacement therapy could be lifesaving, inappropriate life-long therapy with steroids can be harmful. The gold standard test for assessing the hypothalamus-pituitary-adrenal axis (HPA) is the insulin tolerance test (ITT), but due to safety issues is not widely used. Conversely, the ACTH stimulation test is a safer and well-tolerated tool for SAI diagnosis. However, data about its diagnostic accuracy show great variability due to both technical and interpretative aspects, such as dose, route of administration, the timing of the test, and assay used for cortisol measurements. Consequently, the clinical background of the patient and the pretest probability of HPA axis impairment become of paramount importance. We aimed to summarize the recent literature evidence in the conduction and interpretation of the ACTH stimulation test for the diagnosis of SAI to provide updated insights on its correct use in clinical practice.

Baseline and peak cortisol response to the low dose short Synacthen test relates to indication for testing, age and sex

Objective

To review the outcomes of a simplified low dose Synacthen test (LDSST) performed in a tertiary endocrine service over seven years, and to examine for relationships between cortisol measurements and indication for testing, age and sex.

Design

Retrospective, observational study of LDSST performed in 2008 – 2014 (N=335) and 2016-2020 (N=160).

Methods

LDSST were performed by endocrine nurses. Synacthen 500ng/1.73m 2 administered as IV bolus, sampling at 0, 15, 25 and 35 minutes.

Results

Mean (± 1SD) baseline cortisol was 221 ± 120 nmol/L, peak 510 ± 166nmol/L and increment 210 ± 116 nmol/L. 336 (70%) of patients had a normal response (baseline cortisol >100nmol/L, peak >450nmol/L), 78 (16%) a suboptimal response (peak cortisol 350-450nmol/L) and were prescribed hydrocortisone to during periods of stress only, 67 (14%) an abnormal response (baseline <100nmol/L or peak <350nmol/L) and were prescribed daily hydrocortisone. Basal, peak and incremental increases in cortisol were higher in females (p=0.03, p<0.001, p=0.03 respectively). Abnormal results occurred most frequently in patients treated previously with pharmacological doses of glucocorticoids or structural brain abnormalities (p<0.0001).

Discussion

There are concerns that the specificity of the LDSST is poor. The low prevalence and strong association of abnormal results with indication for testing, suggests that over diagnosis occurred infrequently in this clinical setting.

Endocrine disorders in patients with Fabry disease: insights from a reference centre prospective study

CONTEXT

Fabry Disease (FD) is a rare X-linked storage disease characterised by a-galactosidase A deficiency and diffuse organ accumulation of glycosphingolipids. Enzyme replacement and chaperone therapies are only partially effective. It remains unclear if FD-related endocrine disorders contribute to the observed morbidity.

OBJECTIVE

To investigate the function of the endocrine system in patients with FD.

DESIGN

We conducted an observational prospective study from 2017 to 2020.

SETTING AND PATIENTS

We included 77 patients with genetically confirmed FD (27 men, 20/27 Classic, 7/26 Late Onset phenotype, 50 women, 41/50 and 9/50 respectively), who are systematically followed by our reference centre.

RESULTS

36/77 (46.8%) patients had VitD deficiency (25(0H)VitD <20 μg/L) despite the fact that 19/36 (52.8%) were substituted with cholecalciferol. Only 21/77 (27.3%) patients had normal VitD levels without VitD substitution. 11/77 (14.3%) had significant hypophosphatemia (p < 0.80 mmol/L). Three new cases (3.9%) of subclinical, two (2.6%) of overt and six (7.8%) of known hypothyroidism were identified. Of note, men had significantly higher renin levels than women [61.4 (26.1-219.6) vs.25.4 (10.9-48.0) mU/L, p = 0.003]. There were no major abnormalities in adrenal, growth and sex-hormone axes. Patients of Classic phenotype had significantly higher High-Density Lipoprotein Cholesterol (HDL-C) levels (p = 0.002) and in men those levels were positively correlated with globotriaosylsphingosin (Lyso-Gb3) values. 10/77 (13%) of the patients were underweight.

CONCLUSIONS

VitD supplementation should be considered for all patients with FD. Thyroid screening should be routinely performed. Malnutrition should be prevented or treated, particularly in Classic phenotype patients. Overall, our data suggest that FD specialists should actively seek and diagnose endocrine disorders in their patients.

Low-dose short synacthen test with salivary cortisol in patients with suspected central adrenal insufficiency

CONTEXT

The low-dose short synacthen test (LDSST) is recommended for patients with suspected central adrenal insufficiency (AI) if their basal serum cortisol (F) levels are not indicative of an intact hypothalamic-pituitary-adrenal (HPA) axis.

OBJECTIVE

To evaluate diagnostic threshold for salivary F before and 30 min after administering 1 μg of synacthen, performed before 09:30 h.

DESIGN

A cross-sectional study from 2014 to 2020.

SETTING

A tertiary referral university hospital.

PATIENTS

In this study, 174 patients with suspected AI, 37 with central AI and 137 adrenal sufficient (AS), were included.

MAIN OUTCOME MEASURE

The diagnostic accuracy (sensitivity (SE), specificity (SP)) of serum and salivary F levels measured, respectively, by chemiluminescence immunoassay and liquid chromatography-tandem mass spectrometry.

RESULTS

Low basal serum or salivary F levels could predict AI. For the LDSST, the best ROC-calculated threshold for serum F to differentiate AI from AS was 427 nmol/L (SE 79%, SP 89%), serum F > 500 nmol/L reached SP 100%. A salivary F peak > 12.1 nmol/L after administering synacthen reached SE 95% and SP 84% for diagnosing central AI, indicating a conclusive reduction in the likelihood of AI. This ROC-calculated threshold for salivary F was similar to the 2.5th percentile of patients with a normal HPA axis, so it was considered sufficient to exclude AI. Considering AS those patients with salivary F > 12.1 nmol/L after LDSST, we could avoid unnecessary glucocorticoid treatment: 99/150 subjects (66%) had an inadequate serum F peak after synacthen, but salivary F was >12.1 nmol/L in 79 cases, who could, therefore, be considered AS.

CONCLUSIONS

Salivary F levels > 12.1 nmol/L after synacthen administration can indicate an intact HPA axis in patients with an incomplete serum F response, avoiding the need to start glucocorticoid replacement treatment.

Normal Adrenal and Thyroid Function in Patients Who Survive COVID-19 Infection

CONTEXT

The COVID-19 pandemic continues to exert an immense burden on global health services. Moreover, up to 63% of patients experience persistent symptoms, including fatigue, after acute illness. Endocrine systems are vulnerable to the effects of COVID-19 as many glands express the ACE2 receptor, used by the SARS-CoV-2 virion for cellular access. However, the effects of COVID-19 on adrenal and thyroid gland function after acute COVID-19 remain unknown.

OBJECTIVE

Our objectives were to evaluate adrenal and thyroid gland function in COVID-19 survivors.

METHODS

A prospective, observational study was undertaken at the Clinical Research Facility, Imperial College NHS Healthcare Trust, including 70 patients ≥18 years of age, at least 3 months after diagnosis of COVID-19. Participants attended a research study visit (8:00-9:30 am), during which a short Synacthen test (250 µg IV bolus) and thyroid function assessments were performed.

RESULTS

All patients had a peak cortisol ≥450 nmol/L after Synacthen, consistent with adequate adrenal reserve. Basal and peak serum cortisol did not differ according to disease severity or history of dexamethasone treatment during COVID-19. There was no difference in baseline or peak cortisol after Synacthen or in thyroid function tests, or thyroid status, in patients with fatigue (n = 44) compared to those without (n = 26).

CONCLUSION

Adrenal and thyroid function ≥3 months after presentation with COVID-19 was preserved. While a significant proportion of patients experienced persistent fatigue, their symptoms were not accounted for by alterations in adrenal or thyroid function. These findings have important implications for the clinical care of patients after COVID-19.

Fifteen-minute consultation: An approach to the child receiving glucocorticoids

Glucocorticoids (GC) are used in paediatric practice for a broad range of conditions and all paediatricians will prescribe GC, in some form, during their career. A wide variety of GC formulations, doses and administration routes are used for periods of time ranging from days to years. Exposure to exogenous GC can result in hypothalamic-pituitary-adrenal axis suppression-otherwise known as adrenal suppression (AS). Patients with AS may be well most of the time but if GC therapy is reduced or stopped or if additional endogenous GC cannot be generated during illness, then an absolute or relative lack of GC can result in severe illness or death. Here, we highlight the relevance of AS to all paediatricians by providing an overview of the background and discussing the presentation and approaches to the management of this clinical entity.

Glucocorticoid Withdrawal-An Overview on When and How to Diagnose Adrenal Insufficiency in Clinical Practice

Glucocorticoids (GCs) are widely used due to their anti-inflammatory and immunosuppressive effects. As many as 1-3% of the population are currently on GC treatment. Prolonged therapy with GCs is associated with an increased risk of GC-induced adrenal insufficiency (AI). AI is a rare and often underdiagnosed clinical condition characterized by deficient GC production by the adrenal cortex. AI can be life-threatening; therefore, it is essential to know how to diagnose and treat this disorder. Not only oral but also inhalation, topical, nasal, intra-articular and intravenous administration of GCs may lead to adrenal suppression. Moreover, recent studies have proven that short-term (<4 weeks), as well as low-dose (<5 mg prednisone equivalent per day) GC treatment can also suppress the hypothalamic-pituitary-adrenal axis. Chronic therapy with GCs is the most common cause of AI. GC-induced AI remains challenging for clinicians in everyday patient care. Properly conducted GC withdrawal is crucial in preventing GC-induced AI; however, adrenal suppression may occur despite following recommended GC tapering regimens. A suspicion of GC-induced AI requires careful diagnostic workup and prompt introduction of a GC replacement treatment. The present review provides a summary of current knowledge on the management of GC-induced AI, including diagnostic methods, treatment schedules, and GC withdrawal regimens in adults.

A Predictive Risk Score to Diagnose Adrenal Insufficiency in Outpatients: A 7 Year Retrospective Cohort Study

Background: The diagnosis of adrenal insufficiency (AI) requires dynamic tests which may not be available in some institutions. This study aimed to develop a predictive risk score to help diagnose AI in outpatients with indeterminate serum cortisol levels. Methods: Five hundred and seven patients with intermediate serum cortisol levels (3–17.9 µg/dL) who had undergone ACTH (adrenocorticotropin) stimulation tests were included in the study. A predictive risk score was created using significant predictive factors identified by multivariable analysis using Poisson regression clustered by ACTH dose. Results: The seven predictive factors used in the development of a predictive model with their assigned scores are as follows: chronic kidney disease (9.0), Cushingoid appearance in exogenous steroid use (12.0), nausea and/or vomiting (6.0), fatigue (2.0), basal cortisol <9 µg/dL (12.5), cholesterol <150 mg/dL (2.5) and sodium <135 mEq/L (1.0). Predictive risk scores range from 0–50.0. A high risk level (scores of 19.5–50.0) indicates a higher possibility of having AI (positive likelihood ratio (LR+) = 11.75), while a low risk level (scores of <19.0) indicates a lower chance of having AI (LR+ = 0.09). The predictive performance of the scoring system was 0.82 based on the area under the curve. Conclusions: This predictive risk score can help to determine the probability of AI and can be used as a guide to determine which patients need treatment for AI and which require dynamic tests to confirm AI.

Diagnostic performance of morning serum cortisol as an alternative to short synacthen test for the assessment of adrenal reserve; a retrospective study

OBJECTIVE

The short synacthen test (SST) is widely used across the UK to assess adrenal reserve. The main objective of our study was to determine the morning serum cortisol level that will predict adrenal insufficiency (AI) thus reducing our reliance on SST.

DESIGN

This was a single centre retrospective study of 393 SST tests measuring 0 and 60 min cortisol levels after administration of 250 μg of synacthen (synthetic ACTH).

PATIENTS AND METHODS

All the SST tests for patients suspected of primary or secondary AI between April 2016 and October 2018 were included in this study. We used serum to determine circulating cortisol by a newer generation competitive electrochemiluminescence immunoassay (ECLIA) (Roche Diagnostics). A post-ACTH cortisol response of ≥420 nmol/L at 60 min was considered adequate to rule out AI. The data were analysed to ascertain the relationship between 0 min and 60 min serum cortisol.

RESULTS

A total of 393 SST results were included in this study. Overall, a total of 332 (84.5%) subjects achieved sufficient serum cortisol level at 60 min, while 61 subjects (15.5%) showed insufficient response. Using the logistic regression, we determined that a morning basal serum cortisol level of ≥354 nmol/L was able to predict normal adrenal function with 100% sensitivity. We were unable to find a lower cut-off value below which SST will not be required. By using this proposed cut-off point, approximately 37% of the SSTs tests could be avoided.

CONCLUSIONS

Basal morning serum cortisol can be safely used as a first step in the evaluation of patients with suspected AI. This will enhance the number of patients being screened for this condition.

Pharmacodynamic studies of nasal tetracosactide with salivary glucocorticoids for a noninvasive Short Synacthen Test

CONTEXT

The Short Synacthen Test (SST) is the gold standard for diagnosing adrenal insufficiency. It requires invasive administration of Synacthen, venous sampling, and is resource-intensive.

OBJECTIVE

To develop a nasally administered SST, with salivary glucocorticoids measurement, to assess the adrenal response.

DESIGN

We conducted 5 studies: 4 open-label, sequence-randomized, crossover, pharmacodynamic studies testing 6 doses/formulations and a repeatability study. Additionally, pharmacokinetic analysis was undertaken using our chosen formulation, 500 µg tetracosactide with mucoadhesive chitosan, Nasacthin003, in our pediatric study.

SETTING

Adult and children's clinical research facilities.

PARTICIPANTS

A total of 36 healthy adult males and 24 healthy children.

INTERVENTION

We administered all 6 nasal formulations using an European regulator endorsed atomization device. The IV comparators were 250 µg or 1 µg SST.

MAIN OUTCOME MEASURES

We analyzed paired blood and saliva samples for plasma cortisol and salivary cortisol and cortisone.

RESULTS

The addition of chitosan to tetracosactide and dose escalation increased peak cortisol response (P = 0.01 and 0.001, respectively). The bioavailability of Nasacthin003 was 14.3%. There was no significant difference in plasma cortisol at 60 minutes between 500 µg Nasacthin003 and 250 µg IV Synacthen (P = 0.17). The repeatability coefficient at 60 minutes was 105 nmol/L for IV Synacthen and salivary cortisol and cortisone was 10.3 and 21.1 nmol/L, respectively. The glucocorticoid response in children was indistinguishable from that of adults.

CONCLUSIONS

Nasal administration of Nasacthin003 generates equivalent plasma cortisol values to the 250-µg IV SST and, with measurement at 60 minutes of salivary cortisol or cortisone, provides a noninvasive test for adrenal insufficiency.

New Insights and Methods in the Approach to Thalassemia Major: The Lesson From the Case of Adrenal Insufficiency

Background: Thalassemia Major (TM) is a complex pathology that needs a highly skilled approach. Endocrine comorbidities are nowadays the most important complications, including hypogonadism, hypothyroidism, diabetes mellitus, and bone diseases. Recent works stated that there could be a relevant prevalence of adrenal insufficiency (AI) present in TM, and this fact may become crucial, especially in case of major stressful events.

Aim: Test the reliability of the standard test to diagnose AI in a group of TM and correlate it with clinical, hematological, and radiological data.

Methods: We evaluated endocrine damages and the efficacy of iron chelation therapy in 102 patients affected by TM. AI was assessed by tetracosactide (Synacthen) 1 mcg iv (low-dose test, LDT) stimulation test. Patients with a subnormal response (peak cortisol < 500 nmol/L) were followed up to 5 years to check the symptoms and signs of AI.

Results: We found AI in 13.7% of the population studied. We did not find any correlation between AI and all data evaluated. Only female gender seems to be a protective factor. A follow up of the patients affected by AI showed no signs of adrenal crisis, in spite of no replacement therapy.

Conclusions: Our study shows a relevant prevalence of AI in TM, especially in males. The absence of an adrenal crisis, in spite of no replacement therapy, during the long-term follow up, seems to underline that current methods to evaluate AI, in TM, should consider a different and specific diagnostic test or different cut off for diagnosis.

Do we need 30 min cortisol measurement in the short synacthen test: a retrospective study

OBJECTIVE

The short synacthen test (SST) is widely used across the UK to assess adrenal reserve but there remains no consensus on the timing of cortisol sampling to help diagnose adrenal insufficiency. The main objective of our study was to see if both 30 and 60 min sample are required following administration of synacthen to investigate suspected adrenal insufficiency (AI).

DESIGN

This was a single-centre retrospective study of 393 SSTs measuring 0, 30 and 60 min cortisol levels after administration of 250 µg of synacthen.

PATIENTS AND METHODS

All the SSTs for patients suspected of primary or secondary AI between April 2016 and October 2018 were included in this study. The tests were performed as per our hospital protocol. A post-adrenocorticotropic hormone (ACTH) cortisol response of 420 nmol/L at any time point was considered adequate to rule out AI. The data were analysed to ascertain the proportion of patients who achieved this level at 30 and/or 60 min.

RESULTS

A total of 393 SST results were included in this study. Patients were divided into two groups depending on whether (group A) or not (group B) they were on steroids. Overall, a total of 313 (79.6%) subjects achieved cortisol level of ≥420 nmol/L at 30 and 60 min while 19 (4.8%) had late response (ie, insufficient 30 min cortisol levels, rising to ≥420 nmol/L at 60 min). Another 61 subjects (15.5%) showed insufficient response at both 30 and 60 min (ie, failed to achieved level of ≥420 nmol/L). Importantly, there was no patient in either group who had adequate response at 30 min and then failed at 60 min. Patients in group A were more likely to have inadequate response at both 30 and 60 min while patients in group B were more likely to have normal response at both time points.

CONCLUSIONS

Our results suggest that about 5% of people undergoing SST may be inappropriately diagnosed as having AI (and subjected to long-term unnecessary steroid treatment) if the 60 min sample is not maintained. We suggest that 30 min sample does not add any additional diagnostic utility and can be omitted thus simplifying SST even further and saving on cost and resources. We propose that single measurement after 60 min of administration of synthetic ACTH is a sufficient screening test for AI.

Outcomes of the short Synacthen test: what is the role of the 60 min sample in clinical practice?

In recent years, the short Synacthen test (SS) has become the most widely used test to assess adrenal reserve. Despite its frequent use, there are still several areas related to the short Synacthen test (SST), which have no consensus including the optimum sampling times, that is, whether a 60 min post-Synacthen administration cortisol is necessary or not.

Methodology

We performed a retrospective data analysis of 492 SSTs performed on adult patients in a tertiary referral teaching hospital in Ireland. The SSTs were performed in the inpatient and outpatient setting and included patients across all medical disciplines and not exclusively to the endocrinology department.

Results

313 patients had 0, 30 and 60 min samples available for analysis. A total of 270/313 (82%) were deemed to pass the test, that is, cortisol ≥500 nmol/L at both 30 and 60 min. Of the 313 patients, 19 (6%) patients had an indeterminate response, cortisol <500 nmol/L at 30 min, but rising to ≥500 nmol/L on the 60 min sample. Of these 19 patients, only 9/19 patients had a serum cortisol level at 30 min <450 nmol/L, requiring clinical treatment with glucocorticoid replacement. All 24/313 (8%) patients who had insufficient responses at 60 min were also insufficient at 30 min sampling. No individuals passed (≥500 nmol/L) at 30 min and then failed (<500 nmol/L) at 60 min.

Conclusion

Using the 30 min cortisol sample post-Synacthen administration alone identifies clinically relevant adrenal insufficiency in the majority of cases. A small subset of patients have a suboptimal response at 30 min but have a 60 min cortisol concentration above the threshold for a pass. Data regarding the long-term outcomes and management of such patients are lacking and require further study.

Central adrenal insufficiency: open issues regarding diagnosis and glucocorticoid treatment

Background

Central adrenal insufficiency (CAI) is characterized by impaired adrenocorticotropin (ACTH) secretion because of a disease or injury to the hypothalamus or the pituitary, leading to a reduced cortisol production. CAI suspicion arises more frequently in patients with pituitary tumors, cranial irradiation/surgery/injury/infections, as well as after exogenous glucocorticoid withdrawal. Nevertheless, a late diagnosis is not uncommon because CAI may present with nonspecific signs or symptoms, as fatigue or hyponatremia.

Content

The PubMed database was searched (years 1980–2018), using “central adrenal insufficiency” and “ACTH deficiency” as keywords. Subsequently, reference sections of the retrieved articles were searched.

Summary

Dynamic tests are needed when morning basal cortisol levels are not sufficient to exclude or to confirm CAI. Short Synacthen Test (SST) is the most used, and Endocrine Society’s guidelines recommend a cortisol peak >500 nmol/L to exclude CAI. Despite thresholds, understanding the pretest probability of ACTH deficiency (the clinical background of the patient) is essential because the diagnostic accuracy of SST in case of a negative result is suboptimal. Glucocorticoid replacement therapy, able to replicate cortisol circadian rhythm, is required in patients with CAI; fludrocortisone treatment is not necessary. Short-acting glucocorticoid drugs (hydrocortisone or cortisone acetate) are the most used; lower doses than previously used are nowadays recommended to reduce cortisol-related comorbidities. Promising results have been obtained with modified-release hydrocortisone, especially regarding glucose metabolism in patients with primary adrenal insufficiency.

Outlook

An accurate clinical diagnosis and a careful individualized therapy are mandatory in patients with CAI.

Glucocorticoid induced adrenal insufficiency is common in steroid treated glomerular diseases - proposed strategy for screening and management

Background

Glucocorticoids (GCs) are frequently used to treat glomerular diseases but are associated with multiple adverse effects including hypothalamic-pituitary-adrenal axis inhibition that can lead to adrenal insufficiency (AI) on withdrawal. There is no agreed GC tapering strategy to minimise this risk.

Methods

This is a single centre retrospective study, between 2013 to 2016, of patients with glomerular disease on GC therapy for more than 3 months screened for GC induced AI with short synacthen stimulation tests (SSTs) done prior to complete GC withdrawal. We investigated the prevalence of AI, predictors, choice of screening tool and recovery.

Results

Biochemical evidence of GC induced AI was found in 57 (46.3%) patients. Total duration of GC did not differ between those with and without AI (p = 0.711). Patients with GC induced AI had a significantly lower pre-synacthen baseline cortisol as compared to patients without AI. A cut off pre-synacthen baseline cortisol of ≥223.5 nmol/l had a specificity of 100% for identifying individuals without biochemical AI. Patients with GC induced AI took a mean of 8.7 ± 4.6 months (mean ± SD) to recover. Patients with persistent AI had a significantly lower index post-synacthen cortisol measurement.

Conclusions

We demonstrate that biochemically proven GC induced AI is common in patients with glomerular diseases, is not predicted by daily dose or duration and takes a considerable time to recover. The study supports the use of morning basal cortisol testing as an appropriate means to avoid the need for SSTs in all patients and should be performed in all patients prior to consideration of GC withdrawal after 3 months duration.

Hypothalamic-Pituitary and Growth Disorders in Survivors of Childhood Cancer: An Endocrine Society Clinical Practice Guideline

OBJECTIVE

To formulate clinical practice guidelines for the endocrine treatment of hypothalamic-pituitary and growth disorders in survivors of childhood cancer.

PARTICIPANTS

An Endocrine Society-appointed guideline writing committee of six medical experts and a methodologist.

CONCLUSIONS

Due to remarkable improvements in childhood cancer treatment and supportive care during the past several decades, 5-year survival rates for childhood cancer currently are >80%. However, by virtue of their disease and its treatments, childhood cancer survivors are at increased risk for a wide range of serious health conditions, including disorders of the endocrine system. Recent data indicate that 40% to 50% of survivors will develop an endocrine disorder during their lifetime. Risk factors for endocrine complications include both host (e.g., age, sex) and treatment factors (e.g., radiation). Radiation exposure to key endocrine organs (e.g., hypothalamus, pituitary, thyroid, and gonads) places cancer survivors at the highest risk of developing an endocrine abnormality over time; these endocrinopathies can develop decades following cancer treatment, underscoring the importance of lifelong surveillance. The following guideline addresses the diagnosis and treatment of hypothalamic-pituitary and growth disorders commonly encountered in childhood cancer survivors.