Cortisol cut-points for the glucagon stimulation test in the evaluation of hypothalamic pituitary adrenal axis

A Contemporary Approach to the Diagnosis and Management of Adrenal Insufficiency

Adrenal insufficiency (AI) can be classified into three distinct categories based on its underlying causes: primary adrenal disorders, secondary deficiencies in adrenocorticotropin, or hypothalamic suppression from external factors, most commonly glucocorticoid medications used for anti-inflammatory therapy. The hallmark clinical features of AI include fatigue, appetite loss, unintentional weight loss, low blood pressure, and hyponatremia. Individuals with primary AI additionally manifest skin hyperpigmentation, hyperkalemia, and salt craving. The diagnosis of AI is frequently delayed due to the non-specific symptoms and signs early in the disease course, which poses a significant challenge to its early detection prior to an adrenal crisis. Despite the widespread availability of lifesaving glucocorticoid medications for decades, notable challenges persist, particularly in the domains of timely diagnosis while simultaneously avoiding misdiagnosis, patient education for averting adrenal crises, and the determination of optimal replacement therapies. This article reviews recent advancements in the contemporary diagnostic strategy and approaches to optimal treatment for AI.

Impact of the severity of brain injury on secondary adrenal insufficiency in traumatic brain injury patients and the influence of HPA axis dysfunction on prognosis

OBJECTIVE

To investigate secondary adrenal insufficiency post varying traumatic brain injuries' and its impact on prognosis.

METHODS

120 traumatic brain injury patients were categorized into mild, moderate and severe groups based on Glasgow Coma Scale. Adrenal function was evaluated through testing.

RESULTS

Secondary adrenal insufficiency rates were 0% (mild), 22.85% (moderate) and 44.82% (severe). Hypothalamus-pituitary-adrenal axis dysfunction rates were 14.81% (mild), 42.85% (moderate) and 63.79% (severe). Differences among groups were significant (p < .05). Patients with intact hypothalamus-pituitary-adrenal axis had shorter hospital stays and higher Glasgow Coma Scale scores. Receiver operating characteristic analysis of 24-h urinary free cortisol showed an area of 0.846, with a 17.62 μg/24h cutoff, 98.32% sensitivity and 52.37% specificity. In the low-dose adrenocorticotropic hormone test, with an 18 μg/dL cutoff, the receiver operating characteristic area was 0.546, with 46.28% sensitivity and 89.39% specificity.

CONCLUSION

As traumatic brain injury severity increases, secondary adrenal insufficiency incidence rises. The low-dose adrenocorticotropic hormone test is promising for hypothalamus-pituitary-adrenal axis evaluation. Patients with hypothalamus-pituitary-adrenal dysfunction experience prolonged hospitalization and worse prognosis.

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.

Current Screening Strategies for the Diagnosis of Adrenal Insufficiency in Children

Adrenal insufficiency can arise from a primary adrenal disorder, secondary to adrenocorticotropic hormone deficiency, or by suppression of hypothalamic-pituitary-adrenal axis due to exogenous glucocorticoids. Diagnosis of adrenal insufficiency is usually delayed because the initial presentation is often subtle and nonspecific. Clinician awareness and recognition is crucial for timely diagnosis to avoid adrenal crisis. Current screening strategies for the diagnosis of adrenal insufficiency in children in various clinical situations are discussed in this review.

Comparison of glucagon stimulation test and low dose ACTH test in assessing hypothalamic-pituitary-adrenal (HPA) axis in children

INTRODUCTION

Children with a pituitary hormone deficiency are at risk for secondary adrenal insufficiency (AI). A stimulation test is usually performed for diagnosing AI, evaluating both the hypothalamic-pituitary-adrenal and growth hormone (GH)-IGF-1 axes. This single test is preferred by clinicians and is considerably more tolerable by patients. The objective of this study was to evaluate the glucagon stimulation test (GST), which is commonly used to assess both axes. Its diagnostic capability for GH deficiency is high and well accepted, however its utility for determining secondary AI has not been well established.

METHODS

This retrospective study involved 120 patients under 18 years of age with short stature who had undergone both a GST and low dose ACTH stimulation test (LDACTH test). Twenty-six children who had more than 6 months elapsed between the two tests were excluded from the study. The study was conducted on patients of the Pediatric Endocrinology Department at Soroka University Hospital, a tertiary medical centre in Beer Sheva, Israel. Statistical analyses were carried out via IBM SPSS (v. 22), with a significance level determined at p < .05.

RESULTS

Different cortisol cut-off values were assessed for GST and it was determined that the highest combined sensitivity and specificity yielded a cut-off point of 320 nmol/L (56% sensitivity and 83% specificity) while the currently accepted cut-off value (500 nmol/L) yielded 100% sensitivity and 6% specificity.

CONCLUSION

The results of this study show that GST is not an optimal tool for diagnosing secondary AI. Therefore, clinicians using this test should interpret its results with caution.

Isolated adrenocorticotropic hormone deficiency and sialadenitis associated with nivolumab: a case report

BACKGROUND

Immune checkpoint inhibition with anti-PD(L)1 and anti-CTLA4 antibodies has significantly changed cancer treatment during the last 10 years. Nevertheless, boosting the immune system with immune checkpoint inhibition can result in immune-related adverse events, affecting different organ systems, among which the endocrine system is the most affected. However, there are few descriptions of the association of immune-related adverse events, and the pathophysiology of some is still lacking. Here, we report a 70-year-old Caucasian patient treated with nivolumab (anti-PD1 monoclonal antibody) after resection of a unique relapse of melanoma in the neck region who presented with sicca syndrome, extreme fatigue, and weight loss 6 months after the start of anti-PD1 therapy. Blood tests revealed hypoglycemia and secondary hypocortisolism due to isolated adrenocorticotrophic hormone deficiency. Interestingly, brain methionine positron emission tomography/magnetic resonance revealed physiological metabolism of the pituitary gland, which was not increased in size, and no hypophyseal metastasis was detected. The sicca syndrome investigation revealed the absence of anti-SSA/SSB antibodies, while the labial salivary gland biopsy showed lymphoplasmatocytic infiltrates with a focus score of 1. To provide new insights into the physiopathology of the anti-PD1-related sialadenitis, we investigated the distribution of aquaporins 5 by immunostaining on the labial salivary gland acini, and compared this distribution with the one expressed in the primary Sjögren's syndrome. Contrary to patients with primary Sjögren's syndrome (in whom aquaporins 5 is mainly expressed at the basolateral side), but similar to the patients with no sialadenitis, we observed expression of aquaporins 5 at the apical pole. This new finding deserves to be confirmed in other patients with anti-PD1-related sialadenitis. Owing to these immune-related adverse events, anti-PD1 was stopped; nevertheless, the patient developed a new relapse 1 year later (March 2020) in the neck region, which was treated by radiotherapy. Since then, no relapse of melanoma was seen (1.5 years after radiotherapy), but the patient still requires hypophyseal replacement therapy. The sialoadenitis resolved partially.

CONCLUSION

We report a combination of sialoadenitis and hypophysitis explaining extreme fatigue in a patient who was treated in the adjuvant setting with anti-PD1 for a melanoma relapse.

Topical glucocorticoid application causing iatrogenic Cushing's syndrome followed by secondary adrenal insufficiency in infants: two case reports

BACKGROUND

Iatrogenic Cushing's syndrome induced by oral and parenteral glucocorticoid administration is a well-known complication. Immediate withdrawal from exogenous steroids can lead to life-threatening adrenal insufficiency. However, Cushing's syndrome caused by topical treatment with glucocorticoids, such as dexamethasone eye drops or dermal application, is rarely recognized. Young infants in particular are at high risk of suffering from iatrogenic Cushing's syndrome when treated with highly potent topical glucocorticoids.

CASE PRESENTATION

We present a 6-month-old Syrian boy with cushingoid face after dermal clobetasol cream treatment and a 2-year-old Iranian girl with severe growth retardation after application of dexamethasone eye drops. Both families have a migration background and language barriers. In both cases no endogenous cortisol secretion was initially detected in serum and in 24-hour collected urine. After dose reduction of glucocorticoids, severity of symptoms was reversible and serum cortisol was detectable.

DISCUSSION AND CONCLUSION

Young infants are at high risk of developing Cushing's syndrome from topically applied highly potent glucocorticoids. Precise recommendations of treatment dosage, duration, and frequency must be given to the parents, and if necessary, with the help of an interpreter. Monitoring of height and weight as well as regular pediatric follow-ups should be scheduled. Physicians should be aware of potential adrenal insufficiency following withdrawal from long-term topical glucocorticoid treatment, and hydrocortisone treatment should be considered.

Pilot Findings on SARS-CoV-2 Vaccine-Induced Pituitary Diseases: A Mini Review from Diagnosis to Pathophysiology

Since the emergence of the COVID-19 pandemic at the end of 2019, a massive vaccination campaign has been undertaken rapidly and worldwide. Like other vaccines, the COVID-19 vaccine is not devoid of side effects. Typically, the adverse side effects of vaccination include transient headache, fever, and myalgia. Endocrine organs are also affected by adverse effects. The major SARS-CoV-2 vaccine-associated endocrinopathies reported since the beginning of the vaccination campaign are thyroid and pancreas disorders. SARS-CoV-2 vaccine-induced pituitary diseases have become more frequently described in the literature. We searched PubMed/MEDLINE for commentaries, case reports, and case series articles reporting pituitary disorders following SARS-CoV-2 vaccination. The search was reiterated until September 2022, in which eight case reports were found. In all the cases, there were no personal or familial history of pituitary disease described. All the patients described had no previous SARS-CoV-2 infection prior to the vaccination episode. Regarding the type of vaccines administered, 50% of the patients received (BNT162b2; Pfizer-BioNTech) and 50% received (ChAdOx1 nCov-19; AstraZeneca). In five cases, the pituitary disorder developed after the first dose of the corresponding vaccine. Regarding the types of pituitary disorder, five were hypophysitis (variable clinical aspects ranging from pituitary lesion to pituitary stalk thickness) and three were pituitary apoplexy. The time period between vaccination and pituitary disorder ranged from one to seven days. Depending on each case's follow-up time, a complete remission was obtained in all the apoplexy cases but in only three patients with hypophysitis (persistence of the central diabetes insipidus). Both quantity and quality of the published data about pituitary inconveniences after COVID-19 vaccination are limited. Pituitary disorders, unlike thyroid disorders, occur very quickly after COVID-19 vaccination (less than seven days for pituitary disorders versus two months for thyroid disease). This is partially explained by the ease of reaching the pituitary, which is a small gland. Therefore, this gland is rapidly overspread, which explains the speed of onset of pituitary symptoms (especially ADH deficiency which is a rapid onset deficit with evocative symptoms). Accordingly, these pilot findings offer clinicians a future direction to be vigilant for possible pituitary adverse effects of vaccination. This will allow them to accurately orient patients for medical assistance when they present with remarkable symptoms, such as asthenia, polyuro-polydipsia, or severe headache, following a COVID-19 vaccination.

Performance of glucagon stimulation test in diagnosing central adrenal insufficiency in children when utilising the Roche Elecsys® cortisol II assay: a pilot study

OBJECTIVES

The glucagon stimulation test (GST) is used for the simultaneous assessment of central adrenal insufficiency (CAI) and growth hormone deficiency. The new Roche cortisol II (C II) assay was recently introduced, confounding interpretation of the GST. The performance of the GST in diagnosing central adrenal insufficiency (CAI), utilising the C II assay, was therefore compared with that of the overnight metyrapone test (ONMTPT).

METHODS

A diagnostic accuracy study was performed by retrospectively analysing folders and laboratory records of 25 children and adolescents investigated for hypopituitarism with the GST and the ONMTPT between September 2016 and December 2019. The peak serum cortisol (C) of the GST, the post-metyrapone serum 11-deoxycortisol and adrenocorticotropin levels of the ONMTPT were recorded. Diagnostic performance of the GST at a previously suggested cut-off of 374 nmol/L was evaluated.

RESULTS

Seventeen boys and 8 girls, aged 1.7-16.3 years (median 7.3 years) were identified. The sensitivity of the post-GST C-level at 374 nmol/L was 0.40 (95% confidence interval [CI] 0.17-0.69), specificity 0.64 (95% CI 0.39-0.84), positive predictive value 0.44 (95% CI 0.19-0.73), negative predictive value 0.60 (95% CI 0.36-0.80), accuracy 0.54 (95% CI 0.35-0.72), positive likelihood ratio (+LR) 0.93 (95% CI 0.49-1.77) and negative LR 1.12 (95% CI 0.40-3.15). The area under the receiver of operating characteristics (ROC) curve was 0.379 (95% CI 0.142-0.615).

CONCLUSIONS

This study suggests that the GST at any C II cut-off cannot replace the ONMTPT as a diagnostic test for CAI in children. Findings should be confirmed in a larger study.

Central adrenal insufficiency: who, when, and how? From the evidence to the controversies - an exploratory review

Central adrenal insufficiency (CAI) is a life-threatening disorder. This occurs when ACTH production is insufficient, leading to low cortisol levels. Since corticosteroids are crucial to many metabolic responses under organic stress and inflammatory conditions, CAI recognition and prompt treatment are vital. However, the diagnosis of CAI is challenging. This is not only because its clinical presentation is usually oligosymptomatic, but also because the CAI laboratory investigation presents many pitfalls. Thus, the clarification of when to use each test could be helpful in many contexts. The CAI challenge is also involved in treatment: Several formulations of synthetic steroids exist, followed by the lack of a biomarker for glucocorticoid replacement. This review aims to access all available literature to synthesize important topics about who should investigate CAI, when it should be suspected, and how CAI must be treated.

Glucagon-stimulated copeptin measurements in the differential diagnosis of diabetes insipidus: a double-blind, randomized, placebo-controlled study

BACKGROUND

The differential diagnosis of diabetes insipidus is challenging. The most reliable approaches are copeptin measurements after hypertonic saline infusion or arginine, which is a known growth hormone secretagogue but has recently also been shown to stimulate the neurohypophysis. Similar to arginine, glucagon stimulates growth hormone release, but its effect on the neurohypophysis is poorly studied.

DESIGN

Double-blind, randomized, placebo-controlled trial including 22 healthy participants, 10 patients with central diabetes insipidus, and 10 patients with primary polydipsia at the University Hospital Basel, Switzerland.

METHODS

Each participant underwent the glucagon test (s.c. injection of 1 mg glucagon) and placebo test. The primary objective was to determine whether glucagon stimulates copeptin and to explore whether the copeptin response differentiates between diabetes insipidus and primary polydipsia. Copeptin levels were measured at baseline, 30, 60, 90, 120, 150, and 180 min after injection.

RESULTS

In healthy participants, glucagon stimulated copeptin with a median increase of 7.56 (2.38; 28.03) pmol/L, while placebo had no effect (0.10 pmol/L (-0.70; 0.68); P < 0.001). In patients with diabetes insipidus, copeptin showed no relevant increase upon glucagon, with an increase of 0.55 (0.21; 1.65) pmol/L, whereas copeptin was stimulated in patients with primary polydipsia with an increase of 15.70 (5.99; 24.39) pmol/L. Using a copeptin cut-off level of 4.6pmol/L had a sensitivity of 100% (95% CI: 100-100) and a specificity of 90% (95% CI: 70-100) to discriminate between diabetes insipidus and primary polydipsia.

CONCLUSION

Glucagon stimulates the neurohypophysis, and glucagon-stimulated copeptin has the potential for a safe, novel, and precise test in the differential diagnosis of diabetes insipidus.

Adrenal insufficiency in HIV/AIDS: a review

INTRODUCTION

Adrenal insufficiency (AI) is one of the most common potentially life-threatening endocrine complications in people living with human immunodeficiency virus (PLHIV) infection and acquired immunodeficiency syndrome (AIDS).

AREAS COVERED

In this review, the authors explore the definitions of relative AI, primary AI, secondary AI and peripheral glucocorticoid resistance in PLHIV. It also focuses on the pathophysiology, etiology, diagnosis and management of this endocrinopathy in PLHIV. A literature review was conducted through Medline and Google Scholar search on the subject.

EXPERT OPINION

Physicians need to be aware of the endocrinological implications of HIV infection and its treatment, especially CYP3A4 enzyme inhibitors. A high index of clinical suspicion is needed in the detection of AI, especially in PLHIV, as it may present insidiously with nonspecific signs and symptoms and may be potentially life threatening if left untreated. Patients with overt primary and secondary AI require glucocorticoid replacement therapy. Overt primary AI also necessitates mineralocorticoid replacement. On the other hand, the management of relative AI remains controversial. In order to reduce the risk of adrenal crisis during periods of stress, the short-term use of glucocorticoids may be necessary in relative AI.

Long-term corticosteroid use, adrenal insufficiency and the need for steroid-sparing treatment in adult severe asthma

Secondary adrenal insufficiency (AI) occurs as the result of any process that disrupts normal hypothalamic and/or anterior pituitary function and causes a decrease in the secretion of steroid hormones from the adrenal cortex. The most common cause of secondary AI is exogenous corticosteroid therapy administered at supraphysiologic dosages for ≥ 1 month. AI caused by oral corticosteroids (OCS) is not well-recognized or commonly diagnosed but is often associated with reduced well-being and can be life-threatening in the event of an adrenal crisis. Corticosteroid use is common in respiratory diseases, and asthma is a representative condition that illustrates the potential challenges and opportunities related to corticosteroid-sparing therapies. For individuals with severe asthma (approximately 5%-10% of all cases), reduction or elimination of maintenance OCS without loss of control can now be accomplished with biologic therapies targeting inflammatory mediators. However, the optimal strategy to ensure early identification and treatment of AI and safe OCS withdrawal in routine clinical practice remains to be defined. Many studies with biologics have involved short evaluation periods and small sample sizes; in addition, cautious approaches to OCS tapering in studies with a placebo arm, coupled with inconsistent monitoring for AI, have contributed to the lack of clarity. If the goal is to greatly reduce and, where possible, eliminate long-term OCS use in severe asthma through the increasing adoption of biologic treatments, there is an urgent need for clinical trials that address both the speed of OCS withdrawal and how to monitor for AI.

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.

[The glucagon test in diagnosis of secondary adrenal insufficiency after craniospinal irradiation: the feasibility of application, the features of performing the test, and its diagnostic informativity]

BACKGROUND

The glucagon test (GT) is a promising alternative to the insulin hypoglycemia test (IHT) in diagnosis of secondary adrenal insufficiency (SAI).

AIM

To study the feasibility of using the GT in patients after craniospinal irradiation and to determine the cut-off value to rule out SAI.

METHODS

A total of 28 patients (14 males and 14 females) with the median age of 19 years (17; 23) who had undergone combination treatment (surgery, craniospinal irradiation (35 Gy) with boost to the tumor bed, and polychemotherapy) of extrapituitary brain tumors no later than 2 years before study initiation and 10 healthy volunteers of matching sex and age were examined. All the subjects underwent the GT and IHT with an interval of at least 57 days. The cortisol, ACTH, and glucose levels were measured.

RESULTS

Twelve out of 28 patients were diagnosed with SAI according to the IHT results. ROC analysis revealed that cortisol release during the GT 499 nmol/L ruled out SAI [100% sensitivity (Se); 62% specificity (Sp)], while the absence of a rise 340 nmol/l verified SAI (Sp 100%; 55% Se). For GT, the area under a curve (AUC) was 93.6%, which corresponds to a very good diagnostic informativity. In 19 patients, the IHT and GT results were concordant (in ten patients, the release of cortisol occurred above the cut-off value in both tests; no release was detected in nine patients). In nine cases, the results were discordant: the maximum cortisol level detected in the GT was 500 nmol/l, but the IHT results ruled out SAI (the GT yielded a false positive outcome). Contrariwise, in three (10.7%) patients the release of cortisol detected in the GT was adequate, while being insufficient in the IHT test. Adverse events (nausea) were reported during the GT test in 9 (25%) subjects; one patient had hypoglycemia (1.8 mmol/l).

CONCLUSION

GT is highly informative and can be used as a first-level stimulation test for ruling out SAI in patients exposed to craniospinal irradiation performed to manage brain tumors. The cortisol level of 500 nmol/L is the best cut-off value for ruling out SAI according to the GT results. The insulin hypoglycemia test is used as the second-level supporting test in patients with positive GT results.

Long-acting intramuscular ACTH stimulation test for the diagnosis of secondary adrenal insufficiency in children

Background The diagnosis of adrenal insufficiency (AI) is based on the basal and stimulated levels of serum cortisol in response to the short Synacthen test (SST). In patients with secondary AI (SAI) due to hypothalamic-pituitary-adrenal (HPA) axis defects, the SST has been validated against the insulin tolerance test (ITT), which is the gold standard. However, injection Synacthen is not easily available in some countries, and endocrinologists often use Acton-Prolongatum (intramuscular [IM] long-acting adrenocorticotropic hormone [ACTH]) in place of Synacthen. There are no studies validating the use of IM-ACTH in children with suspected AI. We evaluated the diagnostic value of the IM-ACTH test against the ITT for the diagnosis of SAI in children. Methods All children with suspected growth hormone deficiency (GHD) undergoing a routine ITT were evaluated using the IM-ACTH test within 1 week. Results Forty-eight patients (36 boys/12 girls, age range: 5-14 years) were evaluated using both the ITT and the IM-ACTH test. Twenty-eight patients had a normal cortisol response (≥18 μg/dL, 500 nmol/L) in the ITT and 20 had low values. In patients with a normal cortisol response on the ITT, the peak value obtained after the IM-ACTH test was higher than that on the ITT (28.7 μg/dL [± 8.8] vs. 23.8 μg/dL [± 4.54], respectively; p=0.0012). Compared to the ITT, the sensitivity and specificity of the IM-ACTH test for the diagnosis of SAI at cortisol cut-offs <18 μg/dL (500 nmol/L) and <22 μg/dL (600 nmol/L) were 57.1% and 92.8%, and 100% and 73.5%, respectively. Conclusions A peak cortisol value <18 μg/dL on the IM-ACTH test is highly suggestive of SAI, whereas a value >22 μg/dL rules out SAI.