Improvement in clinical features of hypercortisolism during osilodrostat treatment: findings from the Phase III LINC 3 trial in Cushing's disease.

PURPOSE: Cushing's disease is associated with substantial morbidity and impaired quality of life (QoL) resulting from excess cortisol exposure. The current study explored improvements in clinical signs and additional specific manifestations of hypercortisolism during osilodrostat (potent oral 11ß-hydroxylase inhibitor) therapy by degree of control of mean urinary free cortisol (mUFC). METHODS: LINC 3 (NCT02180217) was a prospective, open-label, 48-week study of osilodrostat (starting dose: 2 mg bid; maximum: 30 mg bid) that enrolled 137 adults with Cushing's disease and mUFC > 1.5 times the upper limit of normal (ULN). mUFC (normal range 11‒138 nmol/24 h), cardiometabolic parameters (blood pressure, weight, waist circumference, body mass index, total cholesterol, fasting plasma glucose, glycated haemoglobin), physical manifestations of hypercortisolism (facial rubor, striae, fat distribution, bruising, hirsutism [females], muscle atrophy) and QoL were evaluated. mUFC was defined as controlled if ≤ ULN, partially controlled if > ULN but ≥ 50% reduction from baseline, and uncontrolled if > ULN and < 50% reduction from baseline. Concomitant medications were permitted throughout the study. RESULTS: At weeks 24 and 48, respectively, mUFC was controlled in 93 (67.9%) and 91 (66.4%) patients, partially controlled in 20 (14.6%) and 13 (9.5%), and uncontrolled in 24 (17.5%) and 33 (24.1%). Overall, mean improvements from baseline in cardiometabolic at week 24 were greater in patients with controlled or partially controlled versus uncontrolled mUFC; at week 48, improvements occurred irrespective of mUFC control. Generally, physical manifestations and QoL progressively improved from baseline irrespective of mUFC control. CONCLUSIONS: Improvements in clinical signs and additional specific manifestations of hypercortisolism associated with Cushing's disease occurred alongside decreases in mUFC. Trial registration NCT02180217 (first posted July 2014).

High variability in baseline urinary free cortisol values in patients with Cushing's disease.

OBJECTIVE: Twenty-four-hour urinary free cortisol (UFC) sampling is commonly used to evaluate Cushing's syndrome. Because there are few data on UFC variability in patients with active Cushing's disease, we analysed baseline UFC in a large patient cohort with moderate-to-severe Cushing's disease and assessed whether variability correlates with hypercortisolism severity. These data will help clinicians establish the minimum number of UFC samples required to obtain reliable data. DESIGN: Observational study (enrolment phase of Phase III study). METHODS: Patients (n = 152) with persistent/recurrent or de novo Cushing's disease and mean UFC (mUFC) ≥1·5×ULN (normal: 30-145 nmol/24 h) were included. Mean UFC level was calculated from four 24-h urine samples collected over 2 weeks. RESULTS: Over 600 24-h UFC samples were analysed. The mUFC levels of samples 1 and 2 and samples 3 and 4 were 1000 nmol/24 h (SD 1872) and 940 nmol/24 h (SD 2148), respectively; intrapatient coefficient of variation (CV) was 38% for mUFC. The intrapatient CV using all four samples was 52% (95% CI: 48-56). The intrapatient CV was 51% (95% CI: 44-58) for samples 1 and 2, 49% (95% CI: 43-56) for samples 3 and 4 and 54% (95% CI: 49-59) for samples 1, 2 and 3. Variability in mUFC increased as UFC levels increased. There were no correlations between UFC and clinical features of hypercortisolism. CONCLUSIONS: There is intrapatient variability of approximately 50% in 24-h UFC measurements, which is relevant to targets set to estimate any treatment effect. Analysing more than two 24-h collection periods in individual patients does not result in a relevant decrease in variability. Interestingly, UFC levels did not correlate with hypercortisolism severity.

Guidelines for the management of gastroenteropancreatic neuroendocrine (including carcinoid) tumours (NETs).

These guidelines update previous guidance published in 2005. They have been revised by a group who are members of the UK and Ireland Neuroendocrine Tumour Society with endorsement from the clinical committees of the British Society of Gastroenterology, the Society for Endocrinology, the Association of Surgeons of Great Britain and Ireland (and its Surgical Specialty Associations), the British Society of Gastrointestinal and Abdominal Radiology and others. The authorship represents leaders of the various groups in the UK and Ireland Neuroendocrine Tumour Society, but a large amount of work has been carried out by other specialists, many of whom attended a guidelines conference in May 2009. We have attempted to represent this work in the acknowledgements section. Over the past few years, there have been advances in the management of neuroendocrine tumours, which have included clearer characterisation, more specific and therapeutically relevant diagnosis, and improved treatments. However, there remain few randomised trials in the field and the disease is uncommon, hence all evidence must be considered weak in comparison with other more common cancers.

Relationship between psychological stress and recurrent miscarriage.

Stress arousal may compromise the feedback regulation of the hypothalamo-pituitary-adrenal axis, releasing stress-related biomarkers and thereby affecting establishment of pregnancy. This study examined the relationship between stress and recurrent miscarriage (RM) and the impact of stress on establishment of pregnancy. The stress status of 45 patients with unexplained RM and 40 fertile women was investigated with the Fertility Problem Inventory (FPI), Perceived Stress Scale (PSS), Positive and Negative Affect Schedule, peripheral natural killer (NK) cells and cortisol. Patients with unexplained RM had significantly higher scores on the FPI (P<0.05, adjusted OR 1.02), PSS (P<0.05, adjusted OR 1.13) and Negative Affect scale (P<0.05, adjusted OR 1.12) and lower scores on the Positive Affect scale (P<0.05, adjusted OR 0.89) than fertile controls. Patients who had live births (n=20) during the study period had significantly lower scores in the Positive Affect scale (P<0.05, adjusted OR 1.17) than those who miscarried (n=10). There was a little association between psychological stress measurements and biochemical stress measurements. These results suggest that stress is a risk factor of RM. Within women with RM, moderate stress appears to be associated with improved pregnancy outcome.

Treatment of adrenocorticotropin-dependent Cushing's syndrome: a consensus statement.

OBJECTIVE: Our objective was to evaluate the published literature and reach a consensus on the treatment of patients with ACTH-dependent Cushing's syndrome, because there is no recent consensus on the management of this rare disorder. PARTICIPANTS: Thirty-two leading endocrinologists, clinicians, and neurosurgeons with specific expertise in the management of ACTH-dependent Cushing's syndrome representing nine countries were chosen to address 1) criteria for cure and remission of this disorder, 2) surgical treatment of Cushing's disease, 3) therapeutic options in the event of persistent disease after transsphenoidal surgery, 4) medical therapy of Cushing's disease, and 5) management of ectopic ACTH syndrome, Nelson's syndrome, and special patient populations. EVIDENCE: Participants presented published scientific data, which formed the basis of the recommendations. Opinion shared by a majority of experts was used where strong evidence was lacking. CONSENSUS PROCESS: Participants met for 2 d, during which there were four chaired sessions of presentations, followed by general discussion where a consensus was reached. The consensus statement was prepared by a steering committee and was then reviewed by all authors, with suggestions incorporated if agreed upon by the majority. CONCLUSIONS: ACTH-dependent Cushing's syndrome is a heterogeneous disorder requiring a multidisciplinary and individualized approach to patient management. Generally, the treatment of choice for ACTH-dependent Cushing's syndrome is curative surgery with selective pituitary or ectopic corticotroph tumor resection. Second-line treatments include more radical surgery, radiation therapy (for Cushing's disease), medical therapy, and bilateral adrenalectomy. Because of the significant morbidity of Cushing's syndrome, early diagnosis and prompt therapy are warranted.

Modified-release hydrocortisone for circadian therapy: a proof-of-principle study in dexamethasone-suppressed normal volunteers.

BACKGROUND: All existing long-term glucocorticoid replacement therapy is suboptimal as the normal nocturnal rise and waking morning peak of serum cortisol is not reproduced. AIM: To test whether it is possible to reproduce the normal overnight rise and morning peak in serum cortisol using an oral delayed and sustained release preparation of hydrocortisone (Cortisol(ds)). SUBJECTS AND METHODS: Six healthy normal male volunteers attended on two occasions, in a single-dose, open-label, nonrandomized study. Endogenous cortisol secretion was suppressed by administration of dexamethasone. Cortisol(ds) (formulation A or B) was administered at 2200 h on day 1. Blood samples for measurement of cortisol were taken from 2200 h every 30 min until 0700 h, then hourly until 2200 h on day 2. Fifteen body mass index (BMI)-matched control subjects had serum cortisol levels measured at 20-min intervals for 24 h. Serum cortisol profiles and pharmacokinetics after Cortisol(ds) were compared with those in controls. RESULTS: Formulations A and B were associated with delayed drug release (by 2 h and 4 h, respectively), with median peak cortisol concentrations at 4.5 h (0245 h) and 10 h (0800 h), respectively, thereby reproducing the normal early morning rise in serum cortisol. Total cortisol exposure was not different from controls. CONCLUSIONS: For the first time we have shown that it is possible to mimic the normal circadian rhythm of circulating cortisol with an oral modified-release formulation of hydrocortisone, providing the basis for development of physiological circadian replacement therapy in patients with adrenal insufficiency.

Home administration of lanreotide Autogel by patients with acromegaly, or their partners, is safe and effective.

OBJECTIVE: The introduction of ready-to-use lanreotide Autogel has presented the possibility of patients receiving their acromegaly treatment at home. The objective of this study was to assess the ability of patients (or their partners) to administer repeat, unsupervised, injections of lanreotide Autogel without compromising efficacy or safety. DESIGN: Multicentre (10 UK regional endocrine centres), open-label, nonrandomised, controlled study. Patients elected either to receive/administer unsupervised home injections after injection technique training (Test group) or continued to receive injections from a healthcare professional (Control group). Patients received monthly injections of lanreotide Autogel at their established dose. Effects were monitored for up to 40 weeks. PATIENTS: Thirty patients (15 per treatment group) with acromegaly treated with a stable dose of lanreotide Autogel (60, 90 or 120 mg) for > or = 4 months before screening. Measurements The main outcome measure was the proportion of patients/partners who successfully administered injections throughout the study. RESULTS: All Test group patients/partners qualified to administer injections. Fourteen of 15 patients fulfilled all criteria for successful administration of unsupervised injections (95% confidence interval, 70%-99%). Fourteen of 15 Test and 14/15 Control patients maintained growth hormone and IGF-1 control. Local injection tolerability was good for both treatment groups, and safety profiles were similar. All Test group patients continued with unsupervised injections after the study. CONCLUSIONS: Patients with acromegaly or their partners were able to administer lanreotide Autogel injections with no detrimental effect on efficacy and safety; therefore, unsupervised home injections are a viable alternative to healthcare professional injections for suitably motivated patients.

Assessing the potential impacts of a revised set of on-farm nutrient and sediment 'basic' control measures for reducing agricultural diffuse pollution across England.

The need for improved abatement of agricultural diffuse water pollution represents cause for concern throughout the world. A critical aspect in the design of on-farm intervention programmes concerns the potential technical cost-effectiveness of packages of control measures. The European Union (EU) Water Framework Directive (WFD) calls for Programmes of Measures (PoMs) to protect freshwater environments and these comprise 'basic' (mandatory) and 'supplementary' (incentivised) options. Recent work has used measure review, elicitation of stakeholder attitudes and a process-based modelling framework to identify a new alternative set of 'basic' agricultural sector control measures for nutrient and sediment abatement across England. Following an initial scientific review of 708 measures, 90 were identified for further consideration at an industry workshop and 63 had industry support. Optimisation modelling was undertaken to identify a shortlist of measures using the Demonstration Test Catchments as sentinel agricultural landscapes. Optimisation selected 12 measures relevant to livestock or arable systems. Model simulations of 95% implementation of these 12 candidate 'basic' measures, in addition to business-as-usual, suggested reductions in the national agricultural nitrate load of 2.5%, whilst corresponding reductions in phosphorus and sediment were 11.9% and 5.6%, respectively. The total cost of applying the candidate 'basic' measures across the whole of England was estimated to be £450 million per annum, which is equivalent to £52 per hectare of agricultural land. This work contributed to a public consultation in 2016.

Ineffectiveness of rosiglitazone therapy in Nelson's syndrome.

BACKGROUND: Peroxisome proliferator-activated receptor (PPAR)-gamma agonists have been proposed as therapy to lower plasma ACTH in Cushing's disease. Cyclical secretion of ACTH may, however, explain some of the responses seen. Patients with Nelson's syndrome have persistently high levels of ACTH and may be a better model for examining new therapies to elevated ACTH levels. OBJECTIVE: The objective of the study was to assess whether high-dose rosiglitazone therapy reduces circulating ACTH levels in Nelson's syndrome, a model of ACTH hypersecretion for which no established medical therapy exists. DESIGN: The design was an open-label, prospective, nonrandomized study over 14 wk. SETTING: The study was conducted at a university teaching hospital. PATIENTS: Six patients with Nelson's syndrome participated in the study. METHODS: Patients were assessed at -2, 0, 4, 8, and 12 wk. Rosiglitazone 12 mg/d was administered between 0 and 8 wk. PPAR-gamma immunoreactivity was assessed in pathological tissue. OUTCOME MEASURE: Plasma ACTH was measured before (0830 h) and 120 min after morning dosing with hydrocortisone (HC). RESULTS: One female withdrew prior to commencing therapy for personal reasons. There was no evidence that ACTH levels changed over time (P = 0.864). The average ACTH level was 1187 ng/liter (95% confidence interval 928-1446) for patients before the HC dose and 432 ng/liter (95% confidence interval 172-692) after the HC dose. PPAR-gamma immunoreactivity was positive in three ACTH-secreting tumors available. CONCLUSIONS: Rosiglitazone 12 mg/d did not change circulating ACTH over time, despite PPAR-gamma receptor expression in the tumor tissue. However, this does not preclude the possibility that other patients may respond or that higher doses of rosiglitazone or more potent agonists might prove useful treatment.

Linkage of the angiotensinogen gene locus to human essential hypertension in African Caribbeans.

The renin-angiotensin system regulates blood pressure and sodium balance. The angiotensinogen gene which encodes the key substrate within this system has been linked to essential hypertension in White Europeans. It has been suggested that people of West African ancestry may have a different genetic basis for hypertension. In this study we have tested whether there is linkage of the angiotensinogen gene to essential hypertension in African Caribbeans from St. Vincent and the Grenadines. DNA from 63 affected sibling pairs with hypertension was tested for linkage by analyzing whether there was excess allele sharing among siblings genotyped using an angiotensinogen dinucleotide repeat sequence. There was significant support for linkage (T = 3.07, P = 0.001) and association of this locus to hypertension (chi 2 = 50.2, 12 degrees of freedom, P << 0.001). A DNA polymorphism which alters methionine to threonine at position 235 (M235T) within the angiotensinogen peptide has been associated previously with hypertension. However, we found no association of this variant with hypertension in this study. These findings provide support for linkage and association of the angiotensinogen locus to hypertension in African Caribbeans and suggest some similarities in the genetic basis of essential hypertension in populations of different ethnicity.

Pasireotide: successful treatment of a sparsely granulated tumour in a resistant case of acromegaly.

The granulation pattern of somatotroph adenomas is well known to be associated with differing clinical and biochemical characteristics, and it has been shown that sparsely granulated tumours respond poorly to commonly used somatostatin receptor ligands (SRLs). We report a challenging case of acromegaly with a sparsely granulated tumour resistant to multiple modalities of treatment, ultimately achieving biochemical control with pasireotide. A 26-year-old lady presented with classical features of acromegaly, which was confirmed by an oral glucose tolerance test. Insulin-like growth factor 1 (IGF1) was 1710 µg/L (103-310 µg/L) and mean growth hormone (GH) was >600 U/L. MRI scan showed a 4 cm pituitary macroadenoma with suprasellar extension and right-sided cavernous sinus invasion. She underwent trans-sphenoidal pituitary surgery. Histology displayed moderate amounts of sparsely granular eosinophilic cytoplasm, staining only for GH. Postoperative investigations showed uncontrolled disease (IGF1:1474 µg/L, mean GH:228 U/L) and residual tumour in the cavernous sinus. She received external beam fractionated radiation. Over the years, she received octreotide LAR (up to 30 mg), lanreotide (up to 120 mg) two weekly, cabergoline, pegvisomant and stereotactic radiosurgery to no avail. Only pegvisomant resulted in an element of disease control; however, this had to be stopped due to abnormal liver function tests. Fifteen years after the diagnosis, she was started on pasireotide 40 mg monthly. Within a month, her IGF1 dropped and has remained within the normal range (103-310 µg/L). Pasireotide has been well tolerated, and there has been significant clinical improvement. Somatostatin receptor subtyping revealed a positivity score of two for both sst5 and sst2a subtypes. LEARNING POINTS: Age, size of the tumour, GH levels on presentation, histopathological type and the somatostatin receptor status of the tumour in acromegaly should be reviewed in patients who poorly respond to first-generation somatostatin receptor ligands.Tumours that respond poorly to first-generation somatostatin receptor ligands, especially sparsely granulated somatotroph adenomas, can respond to pasireotide and treatment should be considered early in the management of resistant tumours.Patients with membranous expression of sst5 are likely to be more responsive to pasireotide.

Patients with chronic pain and abnormal pituitary function require investigation.

Misuse of opioids is associated with abnormalities of pituitary function. Patients with chronic pain frequently complain of fatigue and undergo endocrine testing. To test whether oral opioid treatment causes abnormal pituitary function we prospectively assessed pituitary function in 37 patients with chronic pain who were receiving either oral opioid analgesia or non-opioid analgesia. Oral opioid treatment was not associated with abnormal pituitary function although a few patients had abnormal results mainly related to obesity. Our results suggest that patients with chronic pain who have abnormal endocrine results should have a complete assessment, since abnormal test results cannot be attributed to their analgesia.

DNA methylation and silencing of gene expression.

DNA methylation is associated with the silencing of gene expression. The predominant mechanism involves the methylation of DNA and the subsequent recruitment of binding proteins that preferentially recognize methylated DNA. In turn, these proteins associate with histone deacetylase and chromatin remodelling complexes to cause the stabilization of condensed chromatin. Recent studies have indicated that the opposite might also hold; namely, that targeting of methylation might depend on altered chromatin structure. The family of methyltransferases and methyl-binding proteins is expanding and becoming better characterized. This review will focus on the mechanisms of methylation-associated silencing of gene expression.

The CpG island promoter of the human proopiomelanocortin gene is methylated in nonexpressing normal tissue and tumors and represses expression.

Ectopic secretion of ACTH, from sites such as small cell lung cancer (SCLC), results in severe Cushing's syndrome. ACTH is cleaved from POMC. The syndrome may occur when the highly tissue-specific promoter of the human POMC gene (POMC) is activated. The mechanism of activation is not fully understood. This promoter is embedded within a defined CpG island, and CpG islands are usually considered to be unmethylated in all tissues. We demonstrate that much of this CpG island is methylated in normal nonexpressing tissues, in contrast to somatically expressed CpG island promoters reported to date, and is specifically unmethylated in expressing tissues, tumors, and the POMC-expressing DMS-79 SCLC cell line. A narrow 100-bp region is free of methylation in all tissues. E2F factors binding to the upstream domain IV region of the promoter have been shown to be involved in the expression of POMC in SCLC. We show that these sites are methylated in normal nonexpressing tissues, which will prevent binding of E2F, but are unmethylated in expressing tissue. Methylation in vitro is sufficient for silencing of expression, which is not reversed by treatment with Trichostatin A, suggesting that inhibition of expression may be mediated by means other than recruitment of histone deacetylase activity. The DMS-79 cells lack POMC demethylating activity, implying that the methylation and expression patterns are likely to be set early or before neoplastic transformation, and that targeted de novo methylation might be a potential therapeutic strategy.

A combined test using desmopressin and corticotropin-releasing hormone in the differential diagnosis of Cushing's syndrome.

To assess the ability of desmopressin to differentiate between pituitary and ectopic ACTH-dependent Cushing's syndrome and to determine whether diagnostic accuracy could be improved by administering it together with human sequence CRH, we examined its effects on cortisol and ACTH secretion when given alone or in combination with CRH in patients with Cushing's syndrome of varied etiology and compared these data to the results of a standard CRH test in the same individuals. Each patient was studied on three occasions, in random order, separated by at least 48 h. At 0900 h, via an indwelling forearm cannula, 10 micrograms desmopressin, 100 micrograms CRH, or a combination of the two were given as an iv bolus; thereafter, blood was drawn every 15 min for 2 h. The responses to the individual agents were determined according to the timing and calculation criteria suggested by Nieman et al. (1993). A total of 25 patients with Cushing's syndrome were studied: 17 patients with pituitary-dependent Cushing's syndrome, Cushing's disease (CD); 5 patients with occult ectopic ACTH secretion (EC); and 3 patients with primary adrenal (ACTH-independent) Cushing's syndrome. In this series, the best discrimination among ACTH-dependent patient groups was achieved using the combined test. Using the responses of plasma cortisol, all 17 patients with CD showed a rise greater than any of the 5 patients with EC, whereas 1 patient with CD showed a plasma ACTH response within the range seen in the patients with EC. Plasma cortisol responses to desmopressin alone were seen in 14 of 17 patients with CD and 1 of 5 patients with EC and, after CRH alone, in 15 of 17 patients with CD but in no patient with EC. In contrast, plasma ACTH responses after CRH alone were seen in 14 of 17 patients with CD and 2 of 5 patients with EC and, after desmopressin alone, in 12 of 17 with CD and 3 of 5 with EC, thus indicating overlapping responses between the groups and poorer discrimination. No responses were seen in the ACTH-independent group. These data indicate that desmopressin causes the secretion of ACTH and cortisol in patients with ACTH-dependent Cushing's syndrome, and that in combination with CRH, it may provide an improvement over the standard CRH test in the differential diagnosis of ACTH-dependent Cushing's syndrome. Furthermore, these data suggest that there may be abnormalities in vasopressin receptor function or number in ACTH-secreting tumors.

Angiotensinogen in human essential hypertension.

The candidacy of angiotensinogen for a role in the genetic basis of hypertension is supported by the observation that plasma angiotensinogen levels track with raised blood pressure through families. In addition, transgenic mice with overexpression of a rat angiotensinogen gene develop hypertension, and knockout mice with a disrupted gene and absent angiotensinogen production develop low blood pressure. There are now two studies in populations of white European origin and one in African Caribbeans providing support for a role of the angiotensinogen gene locus in human essential hypertension.

Desmopressin normalizes the blunted adrenocorticotropin response to corticotropin-releasing hormone in melancholic depression: evidence of enhanced vasopressinergic responsivity.

Major depression is associated with significant disturbance in hypothalamic-pituitary-adrenal axis functioning, including blunted release of ACTH in response to CRH infusion. Eight melancholic depressives and eight matched healthy comparison subjects underwent, in random order, the following challenges: placebo, CRH, CRH + DDAVP. Blood for ACTH and cortisol estimation was drawn at -15, 0, 15, 30, 45, 60, 90, and 120 min. A blunted release of ACTH, in response to CRH challenge, was observed in depression (P < 0.01), whereas maximal cortisol responses in both groups were similar, despite elevated baseline levels in depression (P < 0.05). The combined CRH/DDAVP infusion produced similar ACTH and cortisol release in both groups. These results suggest that melancholic depression is associated with enhanced pituitary vasopressinergic responsivity.

Optimal response criteria for the human CRH test in the differential diagnosis of ACTH-dependent Cushing's syndrome.

The CRH test is in widespread use for the differential diagnosis of ACTH-dependent Cushing's syndrome (CS). Despite the greater availability worldwide of human-sequence CRH (hCRH), there are no large series reporting the response criteria that best discriminate between Cushing's disease (CD) and the ectopic ACTH syndrome (EC) when using hCRH, rather than ovine-sequence CRH. We have, therefore, analyzed retrospectively the serum cortisol and plasma ACTH responses to hCRH in patients with ACTH-dependent CS, to develop response criteria that best discriminate between CD and EC. One hundred fifteen consecutive patients with proven ACTH-dependent CS were studied: 101 with CD (78 females; mean age, 40 yr; range, 10-73) and 14 with EC (7 females; mean age, 46 yr; range, 32-69). The response to hCRH was also studied in 30 normal volunteers (NVs; mean age, 29 yr; range, 20-44) with no clinical evidence of CS, and the results were compared. Following basal sampling at -15 and 0 min, hCRH (100 microg iv) was administered via an indwelling forearm cannula at 0900 h and serum cortisol and ACTH were measured at 15-min intervals for 2 h. The mean basal, peak, incremental, and percentage change in the serum cortisol and ACTH at all time points, and combination of time points, were calculated and analyzed to establish the best criteria to discriminate between CD and EC, and also between CD and NVs. The mean serum cortisol concentration in samples obtained at 15 and 30 min after CRH increased by at least 14% above the mean basal in 85 of 100 patients with CD, but in none with EC, giving a sensitivity of 85% at a specificity set at 100%. In contrast, the best plasma ACTH response of a rise of 105%, calculated from the maximal rise, gave only 70% sensitivity at 100% specificity. In the NVs, the maximum cortisol at the mean 15+30 min time point was 615 nmol/liter. Using the 15 and 30 min time points as the reference point, 71 of 100 patients with CD had a rise of serum cortisol greater than 14% and also showed an absolute cortisol level more than 615 nmol/liter. Serum cortisol responses to hCRH can be used to suggest the diagnosis of CD in the majority of patients with this condition, but it should only be used in conjunction with other biochemical and imaging modalities in establishing this important diagnosis. The measurement of plasma ACTH was less helpful in making this distinction, although it may have additional value in excluding ACTH-independent causes of CS. Although we believe that bilateral inferior petrosal sinus sampling remains the single most useful test in discriminating CD from EC in patients with ACTH-dependent CS, hCRH offers rapid diagnostic information and is a useful adjunctive test in establishing the presence of a possible ectopic source.

A comparison of the effects of human and ovine corticotropin-releasing hormone on the pituitary-adrenal axis.

To compare the clinical efficacy of ovine and human sequence corticotropin-releasing hormone (CRH), we examined the effects of both peptides on ACTH and cortisol secretion in normal human volunteers, obese subjects, and patients with pituitary-dependent (Cushing's disease) and adrenal-dependent Cushing's syndrome. All subjects in each group were studied twice in random order. One hundred micrograms of CRH were administered as an iv bolus through an in-dwelling forearm cannula at 0930 h, and thereafter, blood was drawn every 15 min for 2 h for the measurement of ACTH and cortisol. In the normal subjects, the peak ACTH, peak incremental ACTH, and mean area under the curve after CRH treatment were greater with ovine CRH than human CRH, although there was no difference in the cortisol response, however it was analyzed. There was no difference in the ACTH or cortisol response to the two preparations in the obese subjects, and no significant difference was found, for either cortisol or ACTH, between obese subjects and normal volunteers. With both varieties of CRH, Cushing's disease resulted in greater responses for ACTH and cortisol than those seen in the other 2 groups (P < 0.001 for all comparisons), but there was no difference between the sequences. However, a significant cortisol response, defined as an increase of greater than 4 times the coefficient of variation of the assay (24%), was seen in all 10 Cushing's patients with human CRH, but in only 8 with ovine CRH. In 3 patients with adrenal tumors, serum cortisol did not change after the administration of either preparation, whereas plasma ACTH remained undetectable throughout the study. We suggest that although ovine sequence CRH causes more prolonged and greater ACTH, and possibly cortisol, secretion compared to human CRH, the discriminatory value of the CRH test, in terms of either the diagnosis or differential diagnosis of Cushing's syndrome, is comparable for the two peptide sequences.

Menstrual abnormalities in women with Cushing's disease are correlated with hypercortisolemia rather than raised circulating androgen levels.

Menstrual irregularity is a common complaint at presentation in women with Cushing's syndrome, although the etiology has been little studied. We have assessed 45 female patients (median age, 32 yr; range, 16-41 yr) with newly diagnosed pituitary-dependent Cushing's syndrome. Patients were subdivided into 4 groups according to the duration of their menstrual cycle: normal cycles (NC; 26-30 days), oligomenorrhea (OL; 31-120 days), amenorrhea (AM; > 120 days), and polymenorrhea (PM; < 26 days). Blood was taken at 0900 h for measurement of LH, FSH, PRL, testosterone, androstenedione, dehydroepiandrosterone sulfate, estradiol (E2), sex hormone-binding globulin (SHBG), and ACTH; cortisol was sampled at 0900, 1800, and 2400 h. The LH and FSH responses to 100 micrograms GnRH were analyzed in 23 patients. Statistical analysis was performed using the nonparametric Mann-Whitney U and Spearman tests. Only 9 patients had NC (20%), 14 had OL (31.1%), 15 had AM (33.3%), and 4 had PM (8.8%), whereas 3 had variable cycles (6.7%). By group, AM patients had lower serum E2 levels (median, 110 pmol/L) than OL patients (225 pmol/L; P < 0.05) or NC patients (279 pmol/L; P < 0.05), and higher serum cortisol levels at 0900 h (800 vs. 602 and 580 nmol/L, respectively; P < 0.05) and 1800 h (816 vs. 557 and 523 nmol/L, respectively; P < 0.05) and higher mean values from 6 samples obtained through the day (753 vs. 491 and 459 nmol/L, respectively; P < 0.05). For the whole group of patients there was a negative correlation between serum E2 and cortisol at 0900 h (r = -0.50; P < 0.01) and 1800 h (r = -0.56; P < 0.01) and with mean cortisol (r = -0.46; P < 0.05). No significant correlation was found between any serum androgen and E2 or cortisol. The LH response to GnRH was normal in 43.5% of the patients, exaggerated in 52.1%, and decreased in 4.4%, but there were no significant differences among the menstrual groups. No differences were found in any other parameter. In summary, in our study 80% of patients with Cushing's syndrome had menstrual irregularity, and this was most closely related to serum cortisol rather than to circulating androgens. Patients with AM had higher levels of cortisol and lower levels of E2, while the GnRH response was either normal or exaggerated. Our data suggest that the menstrual irregularity in Cushing's disease appears to be the result of hypercortisolemic inhibition of gonadotropin release acting at a hypothalamic level, rather than raised circulating androgen levels.