Risk assessment, diagnosis, and treatment of cancer treatment-related adrenal insufficiency.

INTRODUCTION: Adrenal insufficiency (AI) is an easily treatable, potentially life-threatening condition, which is increasingly recognized in malignancy. The recent introduction of immune checkpoint inhibitors, in particular, and increasing use of tyrosine kinase inhibitors have increased the frequency of AI in patients with malignancy. A review is therefore warranted to summarize current knowledge on the topic and guide safe clinical practices. AREAS COVERED: Malignancy may directly impact the hypothalamic-pituitary-adrenal axis and cause AI, or their treatment including surgery, radiotherapy and medication. In this narrative review, we discuss new causes of AI, recognition of suggestive clinical features, diagnosis and subsequent treatment, aiming to avoid potentially fatal adrenal crisis (AC). Standard literature searching and authors assessment of clinical applicability were used. EXPERT OPINION: Adrenal insufficiency can be easily treated once identified but life threatening if unrecognized. While use of new agents such as immune checkpoint inhibitors (ICIs) is increasing, greater understanding of the mechanism of AI is needed to target prediction tools and enhance risk stratification.

Safety Assessment and Potential Risks of the Glucagon Stimulation Test in the Diagnosis of Secondary Adrenal Insufficiency.

BACKGROUND: Although it takes more time, the Glucagon Stimulation Test (GST) is a reliable measure for assessing growth hormone (GH) and Adrenocorticotropic Hormone (ACTH) secretion. The GST is considered to be a safe test; however, it still has mild side effects and potential risks. OBJECTIVES: The objective of this study was to analyze the side effects of the GST while testing adrenal-insufficient patients. METHODS: This was a prospective study in which GST was performed in eighty-one patients (44 men, 37 women, mean age: 35.83A9.62 years) with the pituitary disorder. The GST consisted of an intramuscular injection of 1 mg of glucagon. Blood samples were collected at baseline, and 30, 60, 90, 120, 150, 180, and 210 min after glucagon injection for cortisol measurements. All patients were asked to report side effects associated with this test. RESULTS: The mean peak blood glucose level under GST was 9.01A.03 mmol/L, and the mean glycemic nadir was 4.34A.75 mmol/L most frequently found during the 30th minute (p <10-3). During the test, 35 subjects (43.2%) had side effects with a mean age of 42.89 A19.75 years. Frequent side effects included: nausea (29.62%), vomiting (27.16%), abdominal cramps (18.51%) and hunger (13.58%). All patients tolerated the test until the end. Adverse effects were significantly more prevalent in patients older than 50 years (p=0.012). CONCLUSIONS: The GST is a reliable alternative to assess the hypothalamic pituitary adrenal axis but should be cautiously used especially in the elderly, despite minor side effects.

Safer care for patients with adrenal insufficiency: weighing the evidence, balancing risks and acknowledging uncertainties.

The National Patient Safety Alert supporting early recognition and treatment of adrenal crisis is a vital new component of care for adults affected by primary adrenal insufficiency. Benefits for patients with secondary and tertiary adrenal insufficiency need to be weighed alongside other considerations such as security of the diagnosis, relative likelihood of adrenal crisis and potential for anxiety and distress from assigning 'physical dependency' in relation to glucocorticoid therapy. All clinicians must be vigilant for and responsive to managing risks of adrenal crisis in at-risk patients, while avoiding diagnostic anchoring in the context of acute illness. More research is required to help define who is at greatest risk of adverse outcomes (including avoidance of therapeutic glucocorticoid therapy for fear of adrenal insufficiency) and a cross-specialty approach is advocated.

Adrenal Insufficiency Caused by Chronic Corticosteroid Use, Identified through Medication Therapy Management.

OBJECTIVE: To report a case of adrenal insufficiency caused by chronic corticosteroid treatment.Summary: This case study describes a 71-year-old Caucasian woman diagnosed with secondary adrenal insufficiency (SAI). She had a long history of multiple medical problems that affected her quality of life. The pharmacist reviewed 18 years (2001-2018) of medical records, including her corticosteroid usage history. The patient had been receiving chronic medium-high dose inhaled corticosteroids for asthma, with intermittent oral prednisone for exacerbations. The pharmacist suspected a possible SAI or tertiary adrenal insufficiency (TAI) caused by hypothalamic pituitary adrenal axis suppression induced by chronic corticosteroid use. After discussions with the patient's primary care physician and a screening adrenal function test, the patient was referred to an endocrinologist, and the diagnosis was confirmed. Low-dose hydrocortisone (<30 mg daily) was prescribed; the patient had improvements in mood, skin hyperpigmentation, and asthma symptoms, which eliminated the routine visits to the emergency room/clinic during the winter season.CONCLUSION: The case illustrated the benefits of utilizing a pharmacist's expertise. A consultant pharmacist can identify an underdiagnosed and rare condition, corticosteroid-induced adrenal insufficiency, through comprehensive medication review in a community medication therapy management service setting.

Variation in the Assessment of Immune-Related Adverse Event Occurrence, Grade, and Timing in Patients Receiving Immune Checkpoint Inhibitors.

Importance: Toxic effects of conventional chemotherapy and molecularly targeted cancer therapies are generally well defined and occur at predictable points. By contrast, owing to their heterogeneous manifestations, unpredictable timing, and clinical overlap with other conditions, immune-related adverse events (irAE) may be more difficult to diagnose and characterize. Objective: To determine concordance of algorithm-driven medical record review by medical oncologists for the characterization of 8 irAE in patients treated with immune checkpoint inhibitors. Design, Setting, and Participants: Cross-sectional study of patients treated with immune checkpoint inhibitors at a National Cancer Institute-designated comprehensive cancer center from November 30, 2015, to March 7, 2018. A sample size of 52 patients provided 80% power to distinguish substantial agreement (κ = 0.85) from poor agreement (κ = 0.5) based on the Cohen κ. Main Outcomes and Measures: Interrater agreement of 2 observers in the occurrence and grade of irAE. Results: Of 52 patients (32 [61.5%] male; mean [SD] age, 69 [9] years) analyzed, 42 (80.8%) had non-small cell lung cancer and all received anti-programmed cell death 1 or anti-programmed cell death ligand 1 antibodies, with 3 patients (5.8%) receiving combinations with anti-cytotoxic T-lymphocyte antigen 4 antibodies. A median (interquartile range) of 82 (47-180) documents were reviewed per case. There was limited or poor interrater agreement on irAE occurrence (Cohen κ, 0.37-0.64), with the exception of hypothyroidism (κ = 0.8). Weighted κ similarly showed limited or poor agreement for irAE grade (κ = 0.31-0.75). Differences in assessed time of onset ranged from 5 to 188 days. As a control for data availability and access, observers had a high degree of agreement for the exact start date (98%) and end date (96%) of immunotherapy administration, suggesting that information interpretation rather than identification largely accounted for assessment differences. In multivariable analysis, therapy duration (adjusted odds ratio, 4.80; 95% CI, 1.34-17.17; P = .02) and Charlson Comorbidity Index (adjusted odds ratio, 4.09; 95% CI, 1.10-15.18; P = .03) were significantly associated with discordant irAE assessment. Conclusions and Relevance: These findings underscore critical challenges in assessing the occurrence, type, timing, and severity of irAE. Apart from hypothyroidism (a condition that has a discrete diagnostic laboratory test and few other likely etiologies during immunotherapy treatment), interobserver agreement was poor. Given the importance of accurate and timely assessment of toxic effects for clinical trials and real-world disease management, efforts to improve irAE diagnosis and characterization are needed.

Comparative assessment of hypothalamic-pituitary-adrenal axis suppression secondary to intrabursal injection of different glucocorticoids: a pilot study.

BACKGROUND: Hypothalamic-pituitary-adrenal axis (HPAA) suppression is the most common and dangerous, although often unrecognized and untreated, side effect of glucocorticoid administration. The risk and duration depend both on patient and treatment characteristics. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) currently represents the gold standard method to evaluate the metabolism of endogenous and exogenous steroids. OBJECTIVE: To assess prevalence, severity, and duration of HPAA suppression subsequent to the injection of two steroids with equivalent potency but different pharmacokinetics. SUBJECTS AND METHODS: Single-blind randomized case-control pilot study. Forty patients (22 F; age 48.7 ± 7.2 years) with shoulder calcific tendinopathy received an intrabursal injection of 40 mg of 6α-methylprednisolone acetate (MA) or triamcinolone acetonide (TA). Just before (T0) and after 1 (T1), 7 (T2), 15 (T3), 30 (T4) and 45 (T5) days, we assessed morning blood cortisol and ACTH by RIA, and 24-h urinary levels of MA, TA and free cortisol by HPLC-MS/MS. RESULTS: HPAA function was normal at baseline. At T1, all patients presented HPAA suppression reaching the lowest cortisol, ACTH and UFC levels, that were similar between groups. At T2, mean cortisol remained lower than at baseline (p < 0.0001) in the TA group. In both groups, mean cortisol and ACTH levels progressively normalized, suggesting HPA recovery, except for three patients in the MA and two in the TA group. UFC levels remained lower than normal (p < 0.0001) up to T5, despite the disappearance of exogenous GCs. No patient developed manifestations of hypocortisolism. CONCLUSIONS: A single 40-mg intrabursal injection of MA or TA is sufficient to suppresses HPAA up to 45 days. Although typically asymptomatic, patients should be instructed to recognize and report symptoms suggestive for hypocortisolism, to provide prompt diagnosis, and eventually, treatment, thus avoiding severe complications.

Assessment of hair cortisol as a potential biomarker for possible adrenal suppression due to inhaled corticosteroid use in children with asthma: A retrospective observational study.

BACKGROUND: Inhaled corticosteroids (ICS) are the recommended long-term control therapy for asthma in children. However, concern exists regarding potential adrenal suppression with chronic ICS use. Our pilot study reported that hair cortisol in children was 50% lower during ICS therapy than prior to therapy, suggestive of adrenal suppression. OBJECTIVE: To evaluate hair cortisol concentration (HCC) as a potential biomarker for possible adrenal suppression from ICS use in children with asthma. METHODS: A retrospective observational study was performed at asthma clinics in Vancouver, Winnipeg, and Toronto, Canada. Children (n = 586) were recruited from July 2012 to December 2014 inclusive of those without asthma, with asthma not using ICS, and with asthma using ICS. The most recent three-month HCC was measured by enzyme immunoassay and compared among the groups. Quantile regression analysis was performed to identify factors potentially affecting HCC. RESULTS: The median HCC was not significantly different among the children: No ICS (n = 47, 6.7 ng/g, interquartile range (IQR) 3.7-9.8 ng/g), ICS Treated (n = 360, 6.5 ng/g, IQR 3.8-14.3 ng/g), and Controls (n = 53, 5.8 ng/g, IQR 4.6-16.7 ng/g). 5.6% of the children using ICS had hair cortisol <2.0 ng/g compared to none in the control groups (P < .05, comparing ICS Treated (20/360) to all Controls combined (0/100)) and only half had been exposed to systemic corticosteroids. Age, sex, BMI, and intranasal corticosteroid use were significantly associated with HCC. CONCLUSIONS: Results suggest HCC may be a potential biomarker for adrenal suppression as a population of children using ICS with HCC < 2.0 ng/g was identified compared to none in the control groups. Further research is needed to determine if those children have or are at risk of adrenal suppression or insufficiency.

GLUCOCORTICOID-INDUCED ADRENAL INSUFFICIENCY: A STUDY OF THE INCIDENCE IN HOSPITAL PATIENTS AND A REVIEW OF PERI-OPERATIVE MANAGEMENT.

OBJECTIVE: Glucocorticoid (GC) pharmacotherapy is an effective treatment for a range of diseases, but exposure can suppress the hypothalamic-pituitary-adrenal axis, leading to glucocorticoid-induced adrenal insufficiency (GC-AI) in some patients. However, the incidence of diagnosed GC-AI and the associated health burden, including the incidence of adrenal crises (ACs), are unknown. Although GC-AI treatment is based on well-established principles, there are no agreed protocols regarding the peri-operative management of exposed patients. The aims of this study were to assess the incidence of diagnosed GC-AI in hospital patients and review current approaches to peri-operative management of surgical patients with GC exposure. METHODS: An analysis of hospital admission data concerning adult patients diagnosed with GC-AI and a review of published recommendations for peri-operative GC cover. RESULTS: Between 2001 and 2013, admission with a diagnosis of GC-AI in New South Wales, Australia was rare (annual average of 22.5 admissions/year) and ACs were even more rare (n = 3). Almost two-thirds (64.4%, n = 188) of the patients with diagnosed GC-AI were aged between 50 and 79 years and 45.2% (n = 132) had a comorbid infection. The current approach to peri-operative management of patients with GC exposure appears to be influenced by both the absence of clear guidelines and historic practices. This results in the exposure of some patients to supraphysiologic doses of GCs during the peri-operative period. CONCLUSION: Hospital admission with a diagnosis of GC-AI (with or without an AC) is very rare. Clear guidelines on peri-operative GC cover are necessary to avoid overreplacement with supraphysiologic doses in susceptible patients. ABBREVIATIONS: AC = adrenal crisis; ACTH = adrenocorticotropic hormone; AI = adrenal insufficiency; CI = confidence interval; GC = glucocorticoid; GC-AI = glucocorticoid-induced adrenal insufficiency; HPA = hypothalamic-pituitary-adrenal; OR = odds ratio.

Assessment of Adrenal Function and Health-Related Quality of Life in Advanced Gastric Cancer Patients Who Received First-Line Chemotherapy.

OBJECTIVE: We performed this prospective study to identify both the incidence of adrenal insufficiency (AI) and health-related quality of life (HRQOL) in advanced gastric cancer (AGC) patients who were treated with the S-1 plus cisplatin (SP) regimen as a first-line palliative chemotherapy. METHODS: We assessed adverse events (AEs) observed in 52 patients who received the SP regimen for AGC between January 2009 and June 2010 using the Common Toxicity Criteria Adverse Events (CTCAE) version 3.0. Adrenal function was assessed at baseline and 12 weeks after chemotherapy using the low-dose adrenocorticotropic hormone stimulation test. HRQOL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire version 3.0 (EORTC-QLQ C30). RESULTS: The incidence of AI was 30.8% (n = 16) and of AE observed 55% (n = 29) among 52 patients after 12 weeks of chemotherapy. Of 29 patients with AE, 34.4% (n = 10) were diagnosed with AI, and of 23 patients without AE, 26.1% (n = 6) were diagnosed with AI. CONCLUSION: The incidence of secondary AI in AGC patients was not rare and was not correlated with the presence of nonspecific AEs. Although patients diagnosed with AI did not show any related symptoms, they are at risk of potentially life-threatening consequences. Thus, the evaluation of AI could be suggested for patients who received chemotherapy.

Single induction dose of etomidate versus other induction agents for endotracheal intubation in critically ill patients.

BACKGROUND: The use of etomidate for emergency airway interventions in critically ill patients is very common. In one large registry trial, etomidate was the most commonly used agent for this indication. Etomidate is known to suppress adrenal gland function, but it remains unclear whether or not this adrenal gland dysfunction affects mortality. OBJECTIVES: The primary objective was to assess, in populations of critically ill patients, whether a single induction dose of etomidate for emergency airway intervention affects mortality.The secondary objectives were to address, in populations of critically ill patients, whether a single induction dose of etomidate for emergency airway intervention affects adrenal gland function, organ dysfunction, or health services utilization (as measured by intensive care unit (ICU) length of stay (LOS), duration of mechanical ventilation, or vasopressor requirements).We repeated analyses within subgroups defined by the aetiologies of critical illness, timing of adrenal gland function measurement, and the type of comparator drug used. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; CINAHL; EMBASE; LILACS; International Pharmaceutical Abstracts; Web of Science; the Database of Abstracts of Reviews of Effects (DARE); and ISI BIOSIS Citation index(SM) on 8 February 2013. We reran the searches in August 2014. We will deal with any studies of interest when we update the review.We also searched the Scopus database of dissertations and conference proceedings and the US Food and Drug Administration Database. We handsearched major emergency medicine, critical care, and anaesthesiology journals.We handsearched the conference proceedings of major emergency medicine, anaesthesia, and critical care conferences from 1990 to current, and performed a grey literature search of the following: Current Controlled Trials; National Health Service - The National Research Register; ClinicalTrials.gov; NEAR website. SELECTION CRITERIA: We included randomized controlled trials in patients undergoing emergency endotracheal intubation for critical illness, including but not limited to trauma, stroke, myocardial infarction, arrhythmia, septic shock, hypovolaemic or haemorrhagic shock, and undifferentiated shock states. We included single (bolus) dose etomidate for emergency airway intervention compared to any other rapid-acting intravenous bolus single-dose induction agent. DATA COLLECTION AND ANALYSIS: Refinement of our initial search results by title review, and then by abstract review was carried out by three review authors. Full-text review of potential studies was based on their adherence to our inclusion and exclusion criteria. This was decided by three independent review authors. We reported the decisions regarding inclusion and exclusion in accordance with the PRISMA statement.Electronic database searching yielded 1635 potential titles, and our grey literature search yielded an additional 31 potential titles. Duplicate titles were filtered leaving 1395 titles which underwent review of their titles and abstracts by three review authors. Sixty seven titles were judged to be relevant to our review, however only eight met our inclusion criteria and seven were included in our analysis. MAIN RESULTS: We included eight studies in the review and seven in the meta-analysis. Of those seven studies, only two were judged to be at low risk of bias. Overall, no strong evidence exists that etomidate increases mortality in critically ill patients when compared to other bolus dose induction agents (odds ratio (OR) 1.17; 95% confidence interval (CI) 0.86 to 1.60, 6 studies, 772 participants, moderate quality evidence). Due to a large number of participants lost to follow-up, we performed a post hoc sensitivity analysis. This gave a similar result (OR 1.15; 95% CI 0.86 to 1.53). There was evidence that the use of etomidate in critically ill patients was associated with a positive adrenocorticotropic hormone (ACTH) stimulation test, and this difference was more pronounced at between 4 to 6 hours (OR 19.98; 95% CI 3.95 to 101.11) than after 12 hours (OR 2.37; 95% CI 1.61 to 3.47) post-dosing. Etomidate's use in critically ill patients was associated with a small increase in SOFA score, indicating a higher risk of multisystem organ failure (mean difference (MD) 0.70; 95% CI 0.01 to 1.39, 2 studies, 591 participants, high quality evidence), but this difference was not clinically meaningful. Etomidate use did not have an effect on ICU LOS (MD 1.70 days; 95% CI -2.00 to 5.40, 4 studies, 621 participants, moderate quality evidence), hospital LOS (MD 2.41 days; 95% CI -7.08 to 11.91, 3 studies, 152 participants, moderate quality evidence), duration of mechanical ventilation (MD 2.14 days; 95% CI -1.67 to 5.95, 3 studies, 621 participants, moderate quality evidence), or duration of vasopressor use (MD 1.00 day; 95% CI -0.53 to 2.53, 1 study, 469 participants). AUTHORS' CONCLUSIONS: Although we have not found conclusive evidence that etomidate increases mortality or healthcare resource utilization in critically ill patients, it does seem to increase the risk of adrenal gland dysfunction and multi-organ system dysfunction by a small amount. The clinical significance of this finding is unknown. This evidence is judged to be of moderate quality, owing mainly to significant attrition bias in some of the smaller studies, and new research may influence the outcomes of our review. The applicability of these data may be limited by the fact that 42% of the patients in our review were intubated for "being comatose", a population less likely to benefit from the haemodynamic stability inherent in etomidate use, and less at risk from its potential negative downstream effects of adrenal suppression.

Assessment of salivary free cortisol levels by liquid chromatography with tandem mass spectrometry (LC-MS/MS) in patients treated with mitotane.

OBJECTIVE: Mitotane is an adrenocytolytic agent used in adrenocortical carcinoma, inducing adrenal insufficiency, requiring replacement treatment. Such therapy is not easy to monitor because of mitotane interference. Salivary cortisol reflects a free fraction of plasma cortisol and may be useful in such patients. DESIGN: The aim of our study was to evaluate salivary cortisol by HPLC coupled to tandem-mass spectrometry (LC-MS/MS) and by an electrochemiluminescence immunoassay (ECLIA) in patients treated with mitotane. We enrolled 6 patients receiving mitotane and 2 Addison disease patients as negative controls and determined salivary cortisol rhythm. We also determined the salivary cortisol rhythm in 8 healthy subjects. Salivary samples (n=112) were assayed by ECLIA, using Roche Modular E170, and by LC-MS/MS. RESULTS: The mean values obtained by ECLIA were significantly higher than those obtained by LC-MS/MS in the mitotane group (p<0.001). In fact, in the group measured by LC-MS/MS, we observed several peaks eluting at a retention time different from the cortisol group, presumably due to cortisol-like analogues. In Addison disease, since steroidogenesis is absent, salivary cortisol values measured by the two methods did not show any significant difference (p=0.61). CONCLUSIONS: Salivary cortisol measured by LC-MS/MS is a selective method, excluding cortisol analogues accumulating in treated patients. Therefore, LC-MS/MS offers an effective system to monitor replacement therapy in mitotane treated patients.

Assessment of adrenal suppression in children with asthma treated with inhaled corticosteroids: use of dehydroepiandrosterone sulfate as a screening test.

BACKGROUND: Inhaled corticosteroids (ICs) are considered first-line therapy for persistent asthma. At medium to high doses, ICs can suppress the hypothalamic-pituitary-adrenal (HPA) axis. Various provocative stimuli have been used to evaluate HPA axis function, but they are labor intensive and time-consuming. Dehydroepiandrosterone sulfate (DHEA-S) is a corticotropin-dependent adrenal androgen precursor that is suppressible in patients treated with ICs. OBJECTIVES: To evaluate DHEA-S as a possible marker for HPA axis dysfunction in children treated with ICs. METHODS: Children with moderate-to-severe persistent asthma and a history of medium- to high-dose IC exposure for at least 6 months were evaluated using low-dose and standard high-dose cosyntropin stimulation testing to assess adrenal function, and DHEA-S levels were compared with the results. RESULTS: Thirteen (59%) of 22 patients exhibited an abnormal cortisol response to cosyntropin. Age- and sex-specific mean DHEA-S z scores were significantly lower in cosyntropin abnormal responders (-1.2822) compared with normal responders (0.2964) (P = .008). The receiver operating characteristic curve for DHEA-S z scores had an area of 0.786 (95% confidence interval, 0.584-0.989), reaching 100% sensitivity with a DHEA-S z score of -1.5966 or less and 100% specificity with a DHEA-S z score greater than 0.0225. CONCLUSIONS: Most children develop biochemical evidence of adrenal suppression after treatment with medium to high doses of ICs. The presence of low DHEA-S levels can be used as a screening test to identify the child who needs more formal testing of the HPA axis.

Suppression of adrenal function by low-dose prednisone: assessment with 24-hour urinary steroid hormone profiles--a review of five cases.

The impact of the synthetic glucocorticoid prednisone on adrenal steroid hormone production was examined using 24-hour urinary steroid hormone profiling. Five women, who were chronically taking low-dose prednisone, were tested, and the relevant literature was reviewed. As expected, adrenal glucocorticoid production, measured by urinary terminal cortisol and cortisone metabolites, was markedly suppressed compared to reference range values (p=0.03). Urinary cortisol and cortisone, reflecting circulating glucocorticoids, were decreased to a lesser extent than their terminal metabolites. Urinary dehydroepiandrosterone (DHEA) excretion was dramatically suppressed (p=0.03), while the downstream androgen metabolites androsterone and etiocholanolone were suppressed to a lesser extent. Aldosterone and tetrahydrocorticosterone production demonstrated modest suppression after prednisone administration, but allo-tetrahydrocorticosterone, which is highly sensitive to adrenocorticotropic hormone (ACTH) secretion, was suppressed to a greater extent. Prednisone administration results in a decrease in ACTH secretion by the anterior pituitary, suppressing synthesis of glucocorticoids, DHEA, and DHEA metabolites. Decreased glucocorticoid synthesis is adaptive, because prednisone is active at the glucocorticoid receptor, but suppression of DHEA synthesis is not mitigated by prednisone. DHEA is an important sex hormone precursor, neurosteroid, and endocrine and immune modulator; therefore, DHEA depletion may have significant adverse consequences in terms of sex hormone production, bone health, endocrine and immune system function, and neuropsychiatric status. Studies of DHEA replacement in patients taking prednisone for lupus demonstrate amelioration of some of these adverse effects.

The low-dose ACTH test does not provide a useful assessment of the hypothalamic-pituitary-adrenal axis in secondary adrenal insufficiency.

OBJECTIVE: The 1 microg ACTH stimulation test has been introduced to improve the sensitivity of ACTH as a test of the integrity of hypothalamic-pituitary-adrenal axis (HPAA). This study aims to compare the sensitivity, specificity and diagnostic accuracy of the "low-dose" 1 microg ACTH (LDACTH) test and the "standard dose" 250 microg ACTH (SDACTH) test, with the overnight metyrapone test (OMT) which assesses the entire HPAA. DESIGN: A prospective evaluation of the performance of SDACTH and LDACTH screening tests in a diverse cohort of patients with possible adrenal insufficiency as routinely encountered in clinical practice using the OMT as the reference method. PATIENTS: A total of 51 patients (26 with asthma on inhaled glucocorticoid, nine with hypopituitarism, three with hypothyroidism, one with hyponatraemia, one with Crohn's disease, one with encephalitis and 10 with non-specific symptoms) each underwent SDACTH, LDACTH and OMT tests in random sequence at least 1 week apart. MEASUREMENTS: Blood was sampled for plasma cortisol levels at 0 and 30 min after intravenous administration of 1 microg and 250 microg of ACTH. Metyrapone 30 mg/kg body weight was taken orally at midnight, and plasma samples were taken for measurement of 11-deoxycortisol and cortisol next morning between 08.00 and 09.00 h. The OMT was deemed to be abnormal when both 11-deoxycortisol and cortisol levels were less than 200 nmol/l. RESULTS: The sensitivity and specificity at an empirical "normal" plasma cortisol threshold value of 500 nmol/l were 67% and 100% for the SDACTH test, and 73% and 81% for the LDACTH test, respectively. As the plasma cortisol cut-off value was increased to 550 nmol/l and 600 nmol/l, the sensitivity of the SDACTH test was 67% and 80% and specificity was 97% and 92%, respectively. The sensitivity of the LDACTH test increased from 93% at plasma cortisol cut-off value of 550 nmol/l to 100% at plasma cortisol cut-off value of 600 nmol/l. However, the specificity of the LDACTH test fell from 72% to 56% as the plasma cortisol cut-off value was increased from 550 nmol/l to 600 nmol/l. A receiver operating characteristic curve demonstrated that the specificity of the SDACTH test was higher than the specificity of the LDACTH test at any given level of sensitivity. CONCLUSIONS: Both the LDACTH and SDACTH tests fail to achieve acceptable levels of sensitivity and specificity to be useful as screening tests for secondary adrenal insufficiency. In this context the OMT can be safely used to assess the integrity of the entire HPAA.

Optimizing the diagnostic criteria for standard (250-microg) and low dose (1-microg) adrenocorticotropin tests in the assessment of adrenal function.

ACTH stimulation is the standard test for assessment of adrenal function. It was suggested that the low dose (1 microg) would be more sensitive for detecting mild secondary adrenal insufficiency than the usual dose of 250 microg. The aim of this study was to find the optimal diagnostic criteria and to compare standard dose test (SDT) with the low dose test (LDT). A group of patients treated with corticosteroids for the 6 months was considered to have hypothalamo-pituitary-adrenal impairment. Studies were performed in 14 corticosteroid-treated and 28 control subjects in random order on 2 consecutive days. Tests were analyzed using the receiver operating characteristic curve method. The best test was cortisol increment at 15 min of the LDT. It was significantly better than the cortisol concentration at 15 min of the SDT, the best test during the SDT (receiver operating characteristic curve area and 95% confidence interval: LDT, 0.997 and 0.956-0.999; SDT, 0.827 and 0.662-0.929; P = 0.0113). For the cortisol increment at 15 min of the LDT at 100% sensitivity, the diagnostic value was 100 mmol/L, and the specificity was 96%. Therefore, the LDT is superior to the standard dose test in the assessment of secondary adrenal insufficiency.