Adrenal Crisis - Definition, Prevention and Treatment: Results from a Delphi Survey

Based on recent data, a total number of about 29 000 patients with adrenal insufficiency can be calculated for Germany, and about 1500 fatalities due to adrenal crises have to be expected within the next decade. Management of adrenal crises is still unsatisfactory. The objectives of this study were to establish consensus for diagnostic criteria, prevention strategies, and treatment recommendations for adrenal crises. The study was conducted from January 2022 to April 2023, using Delphi technique. Four rounds of questionnaires were sent to 45 experts, selected by a coordinating group on behalf of the adrenal section of the German Society of Endocrinology. The survey was implemented online using the REDCap web application. Responses were captured anonymously. During the Delphi process the expert panel developed diagnostic criteria to identify patients likely to have an adrenal crisis. Education about adrenal insufficiency among patients as well as non-endocrine medical personnel were regarded as highly important. It was suggested that recommendations for the management of adrenal insufficiency have to be simplified and made widely available. This study provides pragmatic strategies to identify and treat patients prone to adrenal crisis, thereby highlighting the need for an improved management of patients with adrenal insufficiency.

Morbidity in Patients with Chronic Adrenal Insufficiency - Cardiovascular Risk Factors and Hospitalization Rate Compared to Population Based Controls

Patients with adrenal insufficiency (AI) have been found to have increased cardiovascular morbidity, partly associated with nonphysiologic glucocorticoid replacement. We included two separate cohorts (cohort 1 n=384 patients, cohort 2 n=180 patients) of patients with chronic primary and secondary AI under standard replacement therapy and compared them to two age- and sex-matched population-based studies (SHIP-TREND/DEGS). Odds ratios with 95% CI for hypertension, hyperlipidemia/HLP, type 2 diabetes/T2DM, obesity, and hospitalization with adjustment for confounders were evaluated by logistic regression. Patient cohort 1 had significantly lower ORs for obesity [0.4 (0.3-0.6), p<0.001] and hypertension [0.5 (0.3-0.6), p<0.001] compared to SHIP-TREND and for obesity [0.7 (0.5-0.9), p=0.01], hypertension [0.4 (0.3-0.5), p<0.001] and HLP [0.4 (0.3-0.6), p<0.001] compared to DEGS. In cohort 2, ORs were significantly lower for HLP compared to both SHIP-TREND [0.4 (0.2-0.7), p=0.001] and DEGS [0.3 (0.2-0.5), p<0.001] and for hypertension [0.7 (0.4-0.9), p=0.04] compared to SHIP-TREND. In patients with SAI from cohort 2, ORs for DM2 [2.5 (1.3-4.9) p=0.009], hypertension [2.5 (1.4-4.5), p=0.002] and obesity [1.9 (1.1-3.1), p=0.02] were significantly higher compared to DEGS, whereas ORs for HLP were significantly lower compared to both SHIP [0.3 (0.1-0.6), p=0.002] and DEGS [0.3 (0.1-0.6), p<0.001]. In most of our AI patients treated with conventional glucocorticoid doses, the risk for T2DM, obesity, hypertension, and HLP was not increased. The number of hospitalizations was significantly higher in AI patients compared to controls, which might reflect increased susceptibility but also a more proactive management of concomitant diseases by physicians and patients.

On Primary Adrenal Insufficiency with Normal Concentrations of Cortisol - Early Manifestation of Addison's Disease

Primary adrenal insufficiency (AI) is an endocrine disorder in which hormones of the adrenal cortex are produced to an insufficient extent. Since receptors for adrenal steroids have a wide distribution, initial symptoms may be nonspecific. In particular, the lack of glucocorticoids can quickly lead to a life-threatening adrenal crisis. Therefore, current guidelines suggest applying a low threshold for testing and to rule out AI not before serum cortisol concentrations are higher than 500 nmol/l (18 μg/dl). To ease the diagnostic, determination of morning cortisol concentrations is increasingly used for making a diagnosis whereby values of>350 nmol/l are considered to safely rule out Addison's disease. Also, elevated corticotropin concentrations (>300 pg/ml) are indicative of primary AI when cortisol levels are below 140 nmol/l (5 μg/dl). However, approximately 10 percent of our patients with the final diagnosis of primary adrenal insufficiency would clearly have been missed for they presented with normal cortisol concentrations. Here, we present five such cases to support the view that normal to high basal concentrations of cortisol in the presence of clearly elevated corticotropin are indicative of primary adrenal insufficiency when the case history is suggestive of Addison's disease. In all cases, treatment with hydrocortisone had been started, after which the symptoms improved. Moreover, autoantibodies to the adrenal cortex had been present and all patients underwent a structured national education program to ensure that self-monitored dose adjustments could be made as needed.

Hypoparathyroidism - management, information needs, and impact on daily living from the patients' perspective: results from a population-based survey

PURPOSE

Hypoparathyriodism (hypoPT) is a rare endocrine disorder. It is not known how hypoPT is managed in Germany or whether patients have unmet information needs or impairments in their daily living.

METHODS

HypoPT patients at a minimum of 6 months' post-diagnosis were invited to participate in an online survey through their treating physician or through patient organizations. An extensive questionnaire, which was developed and pilot-tested with hypoPT patients, was administered.

RESULTS

A total of 264 patients with a mean age of 54.5 years (SD: 13.3), 85.2% female and 92% with postsurgical hypoPT, participated in the study. In total, 74% of the patients reported regular monitoring of serum calcium at least every 6 months, with lower control frequencies for phosphate (47%), magnesium (36%), creatinine (54%), and parathyroid hormone (50%), and 24-h urine calcium excretion (36%) on a yearly basis. Information on symptoms of hypo- and hypercalcemia was available in 72 and 45% of the patients. Information needs were related to the disease and its treatment as well as to nutrition, physical activities/sports, and support opportunities. Statistically significant differences for all information needs in association with symptom burden were observed. Hospitalization for hypocalcemia was reported by 32%, nutritional impairments (38%) or impact on work ability (52%) was available among patients with hypoPT.

CONCLUSION

HypoPT patients experience impairments in daily living and report unmet information needs. Patient and physician education regarding hypoPT is one of the key concepts for improving the management of patients with hypoPT.

Questions and Controversies in the Clinical Application of Tyrosine Kinase Inhibitors to Treat Patients with Radioiodine-Refractory Differentiated Thyroid Carcinoma: Expert Perspectives

Notwithstanding regulatory approval of lenvatinib and sorafenib to treat radioiodine-refractory differentiated thyroid carcinoma (RAI-R DTC), important questions and controversies persist regarding this use of these tyrosine kinase inhibitors (TKIs). RAI-R DTC experts from German tertiary referral centers convened to identify and explore such issues; this paper summarizes their discussions. One challenge is determining when to start TKI therapy. Decision-making should be shared between patients and multidisciplinary caregivers, and should consider tumor size/burden, growth rate, and site(s), the key drivers of RAI-R DTC morbidity and mortality, along with current and projected tumor-related symptomatology, co-morbidities, and performance status. Another question involves choice of first-line TKIs. Currently, lenvatinib is generally preferred, due to greater increase in progression-free survival versus placebo treatment and higher response rate in its pivotal trial versus that of sorafenib; additionally, in those studies, lenvatinib but not sorafenib showed overall survival benefit in subgroup analysis. Whether recommended maximum or lower TKI starting doses better balance anti-tumor effects versus tolerability is also unresolved. Exploratory analyses of lenvatinib pivotal study data suggest dose-response effects, possibly favoring higher dosing; however, results are awaited of a prospective comparison of lenvatinib starting regimens. Some controversy surrounds determination of net therapeutic benefit, the key criterion for continuing TKI therapy: if tolerability is acceptable, overall disease control may justify further treatment despite limited but manageable progression. Future research should assess potential guideposts for starting TKIs; fine-tune dosing strategies and further characterize antitumor efficacy; and evaluate interventions to prevent and/or treat TKI toxicity, particularly palmar-plantar erythrodysesthesia and fatigue.

Villus Growth, Increased Intestinal Epithelial Sodium Selectivity, and Hyperaldosteronism Are Mechanisms of Adaptation in a Murine Model of Short Bowel Syndrome

BACKGROUND

Short bowel syndrome results from extensive small bowel resection and induces adaptation of the remaining intestine. Ileocecal resection (ICR) is the most frequent situation in humans. Villus hypertrophy is one hallmark of mucosal adaptation, but the functional mechanisms of mucosal adaptation are incompletely understood.

AIMS

The aim of the study was to characterize a clinically relevant model of short bowel syndrome but not intestinal failure in mice and to identify outcome predictors and mechanisms of adaptation.

METHODS

Male C57BL6/J mice underwent 40% ICR and were followed for 7 or 14 days. Small bowel transection served as control. All mice underwent autopsy. Survival, body weight, wellness score, stool water content, plasma aldosterone concentrations, and paracellular permeability were recorded.

RESULTS

Unlike controls, resected mice developed significant diarrhea with increased stool water. This was accompanied by sustained weight loss throughout follow-up. Villus length increased but did not correlate positively with adaptation. Plasma aldosterone concentrations correlated inversely with body weight at day 14. After ICR, intestinal epithelial (i.e., tight junctional) sodium permeability was increased.

CONCLUSIONS

40% ICR results in moderate to severe short bowel syndrome. Successful adaptation to the short bowel situation involves villus elongation but does not correlate with the degree of villus elongation alone. In addition, increased intestinal epithelial sodium permeability facilitates sodium-coupled solute transport. Hyperaldosteronism correlates with the severity of weight loss, indicates volume depletion, and counterregulates water loss.

Prevalence of Malignancies in Patients With Primary Aldosteronism

CONTEXT

Primary aldosteronism (PA) is the most common cause of secondary hypertension. Aldosterone excess can cause DNA damage in vitro and in vivo. Single case reports have indicated a coincidence of PA with renal cell carcinoma and other tumors. However, the prevalence of benign and malignant neoplasms in patients with PA has not yet been studied.

PATIENTS AND DESIGN

In the multicenter MEPHISTO study, the prevalence of benign and malignant tumors was investigated in 335 patients with confirmed PA. Matched hypertensive subjects from the population-based Study of Health in Pomerania cohort served as controls.

RESULTS

Of the 335 PA patients, 119 (35.5%) had been diagnosed with a tumor at any time, and 30 had two or more neoplasms. Lifetime malignancy occurrence was reported in 9.6% of PA patients compared to 6.0% of hypertensive controls (P = .08). PA patients with a history of malignancy had higher baseline aldosterone levels at diagnosis of PA (P = .009), and a strong association between aldosterone levels and the prevalence of malignancies was observed (P = .03). In total, 157 neoplasms were identified in the PA patients; they were benign in 61% and malignant in 25% of the cases (14% of unknown dignity). Renal cell carcinoma was diagnosed in five patients (13% of all malignancies) and was not reported in controls

CONCLUSION

Compared to hypertensive controls, the prevalence of malignancies was positively correlated with aldosterone levels, tended to be higher in PA patients, but did not differ significantly.

Activating mutations in CTNNB1 in aldosterone producing adenomas

Primary aldosteronism (PA) is the most common cause of secondary hypertension with a prevalence of 5–10% in unreferred hypertensive patients. Aldosterone producing adenomas (APAs) constitute a large proportion of PA cases and represent a surgically correctable form of the disease. The WNT signaling pathway is activated in APAs. In other tumors, a frequent cause of aberrant WNT signaling is mutation in the CTNNB1 gene coding for β-catenin. Our objective was to screen for CTNNB1 mutations in a well-characterized cohort of 198 APAs. Somatic CTNNB1 mutations were detected in 5.1% of the tumors, occurring mutually exclusive from mutations in KCNJ5, ATP1A1, ATP2B3 and CACNA1D. All of the observed mutations altered serine/threonine residues in the GSK3β binding domain in exon 3. The mutations were associated with stabilized β-catenin and increased AXIN2 expression, suggesting activation of WNT signaling. By CYP11B2 mRNA expression, CYP11B2 protein expression, and direct measurement of aldosterone in tumor tissue, we confirmed the ability for aldosterone production. This report provides compelling evidence that aberrant WNT signaling caused by mutations in CTNNB1 occur in APAs. This also suggests that other mechanisms that constitutively activate the WNT pathway may be important in APA formation.

Novel somatic mutations and distinct molecular signature in aldosterone-producing adenomas

Aldosterone-producing adenomas (APAs) are found in 1.5-3.0% of hypertensive patients in primary care and can be cured by surgery. Elucidation of genetic events may improve our understanding of these tumors and ultimately improve patient care. Approximately 40% of APAs harbor a missense mutation in the KCNJ5 gene. More recently, somatic mutations in CACNA1D, ATP1A1 and ATP2B3, also important for membrane potential/intracellular Ca(2) (+) regulation, were observed in APAs. In this study, we analyzed 165 APAs for mutations in selected regions of these genes. We then correlated mutational findings with clinical and molecular phenotype using transcriptome analysis, immunohistochemistry and semiquantitative PCR. Somatic mutations in CACNA1D in 3.0% (one novel mutation), ATP1A1 in 6.1% (six novel mutations) and ATP2B3 in 3.0% (two novel mutations) were detected. All observed mutations were located in previously described hotspot regions. Patients with tumors harboring mutations in CACNA1D, ATP1A1 and ATP2B3 were operated at an older age, were more often male and had tumors that were smaller than those in patients with KCNJ5 mutated tumors. Microarray transcriptome analysis segregated KCNJ5 mutated tumors from ATP1A1/ATP2B3 mutated tumors and those without mutation. We observed significant transcription upregulation of CYP11B2, as well as the previously described glomerulosa-specific gene NPNT, in ATP1A1/ATP2B3 mutated tumors compared to KCNJ5 mutated tumors. In summary, we describe novel somatic mutations in proteins regulating the membrane potential/intracellular Ca(2) (+) levels, and also a distinct mRNA and clinical signature, dependent on genetic alteration.

Indication and technical aspects of adrenal blood sampling

Adrenal disorders are relative frequent with regard to the incidence of adrenal tumors and the high portion in causes of secondary hypertension. Morphological changes in the adrenal glands can lead to very different functional disorders that may be clinically overt or hard to diagnose. On the other hand, they can already be functionally relevant when structural changes are too small to be picked up by imaging. Adrenal venous sampling serves to determine the source of hormone excess through the analysis of adrenal blood. In this manuscript, we call attention to the clinical backgrounds, critical points in praxis, technical aspects and developments in the the field of adrenal venous sampling. The consideration of these important points in the clincal setting may make adrenal vein sampling studies sucessful and help to select patients that qualify for adrenalectomy.

KEY POINTS

• Selective adrenal venous sampling (AVS) currently continues to be the gold standard for localization diagnostics in patients with primary hyperaldosteronism. • Comprehensive standardization of all preceding examinations and AVS is necessary to ensure high success rates. • The method is supported by contrast-enhanced imaging for ensuring proper positioning of the catheter in the adrenal veins and the rapid cortisol assay. • Knowledge of the anatomy and normal variants of the adrenal veins facilitates adrenal venous sampling.

MicroRNA expressions in PMBCs, CD4+, and CD8+ T-cells from patients suffering from autoimmune Addison's disease

Autoimmune Addison's disease (AD) is a rare but potentially life threatening disease. The exact etiology of the immune response to the adrenal gland is still unknown. MicroRNAs (miRNAs) critically control gene-expression and play an important role in regulating the immune response. The aim of this study was to determine key immunoregulatory miRNAs influencing autoimmune adrenal insufficiency. For this purpose selected miRNAs were amplified by a semiquantitative SYBR Green PCR from blood mononuclear cells and after purification from CD4+ and CD 8+ cells of 6 patients with autoimmune adrenal insufficiency and 10 healthy controls. In CD4+ T-cells miRNA 181a*_1 (18.02 in AD vs. 11.99 in CG, p=0.0047) is significantly increased whereas miRNA 200a_1 (12.48 in AD vs. 19.40 in CG, p=0.0003) and miRNA 200a_2* (8.59 in AD vs. 17.94 in CG, p=0.0160) are significantly decreased. miRNA 200a_1 (12.37 in AD group vs. 18.12 in control group, p=0.001) and miRNA 200a_2* (10.72 in AD group vs. 17.84 in control group, p=0.022) are also significantly decreased in CD8+ T-cells. This study could show for the first time a significant change of three defined miRNAs in PBMCs, CD4+, and CD8+ T-cells of autoimmune AD patients in vivo. These data may help to better understand the cause of the autoimmune processes leading to autoimmune AD. They extend our very limited knowledge concerning miRNAs in autoimmune Addison's disease.

Griseofulvin inhibits the growth of adrenocortical cancer cells in vitro

Supernumerary centrosomes and aneuploidy are associated with a malignant phenotype of tumor cells. Centrosomal clustering is a mechanism used by cancer cells with supernumerary centrosomes to solve the threatening problem of multipolar spindles. Griseofulvin is an antifungal substance that interferes with the microtubule apparatus and inhibits centrosomal clustering. It has also been demonstrated that griseofulvin inhibits the growth of tumor cells in vitro and in vivo. However, it is not yet known whether treatment with griseofulvin inhibits growth of adrenocortical tumor cells. We studied the viability and antiproliferative effects of griseofulvin on cultured NCI-H295R adrenocortical carcinoma cells using Wst-1-, BrdUrd-, and [³H]-thymidine assays. For the detection of apoptosis we used a caspase 3/7 cleavage assay and light microscopy techniques. We observed that incubation with griseofulvin for 24-48 h leads to a decrease in the viability and proliferation of NCI-H295R cells in a dose-dependent manner. Significant effects could be observed after incubation with griseofulvin as measured by Wst-1-, BrdUrd-, and [³H]dT- uptake assays. Apoptosis of NCI-H295R cells was increased in a dose-dependent manner up to 4.5-fold after incubation with griseofulvin 40 μM for 24 h as shown by caspase 3/7 cleavage assay and light microscopy. With regard to new treatment strategies for adrenocortical cancer, griseofulvin, and possibly other agents, which interfere with the microtubule apparatus and inhibit centrosomal clustering, may turn out to be interesting targets for further research.

Control of CYP11B2/CYP11B1 expression ratio and consequences for the zonation of the adrenal cortex

Access of corticotropin to glucocorticoid synthesis in adrenocortical cells is provided by the expression of the ACTH receptor (MC2R). Activation of the MC2R increases stimulatory G-protein, adenylyl cyclase, and protein kinase A (PKA) activities. Furthermore, PKA phosphorylates transcription factors that have a stimulating effect on glucocorticoid synthesis. Sensitivity of adrenocortical cells to renin/angiotensin-2 is conferred by the expression of the inhibitory G-protein-linked angiotensin-2 type 1 receptor (AT1R) that additionally associates to the phospholipase C-activating G-protein q. The AT1R is connected to the adrenal potassium sensory system and regulates calcium influx as well as phospholipase C-β (PLC-β) and thus calmodulin kinase-dependent transcription of steroidogenic enzymes. While AT1R signaling suppresses the influence of corticotropin on the generation of cyclic adenosine monophosphate, the expression of the AT1R and its associated enzyme activities are under the control of glucocorticoids. Thus, dominance of one of the two signaling pathways is dependent on two factors: the extracellular concentration of their ligands and the products of their signaling pathways. These findings are in favor of the hypothesis that the centripetal blood flow through the adrenal gland builds up a glucocorticoid gradient creating a morphogenetic field along which adrenal cortical cells adopt different functional states, leading to the typical zonation of the adrenal cortex.

Comparison of the saline infusion test and the fludrocortisone suppression test for the diagnosis of primary aldosteronism

For the diagnosis of primary aldosteronism (PA), confirmatory testing is mandatory and different function tests can be employed. There are, however, sparse data comparing the fludrocortisone suppression test (FST) and the saline infusion test (SIT). Patients with PA (n=90) or essential hypertension (n=65) were studied. They underwent one or the other test or both of them. Using the DPC Siemens aldosterone radioimmunoassay, we found that the SIT led to a stronger suppression of aldosterone than the FST. Post-test aldosterone-to-renin ratios (ARRs) and the percentage of suppression of aldosterone serum concentrations performed worse. The same results were observed in patients who underwent both FST and SIT. Some patients had divergent results in both tests. For the SIT, a lower cutoff value should be used than for the FST for the adequate identification of patients with unilateral PA. Long-term prospective studies are needed to address the question at what cutoff values patients benefit from subtype differentiation of PA. We discuss here possible explanations for divergent results obtained with both tests.

[Kallmann syndrome]

The Kallmann syndrome is a very rare congenital association of gonadotropin-releasing hormone deficiency and hyposmia or anosmia. Clinically it is characterized by low serum concentrations of testosterone and inadequate low levels of luteinizing hormone and follicle-stimulating hormone as well as incomplete sexual maturation, lack of secondary sexual features (facial and body hair growth, deepening of the voice), micropenis and sometimes even cryptorchidism. The reduced or absent sense of smell is typical for the Kallmann syndrome and distinguishes this syndrome from other causes of hypogonadotropic hypogonadism. Additional findings may include synkinesia, hearing loss, unilateral renal aplasia, brachy- or syndactyly, agenesis of corpus callosum, cleft palate and dental agenesis. A 19-year-old man presented to our male infertility clinic with delayed sexual maturation, eunuchoid habitus, micropenis, cryptorchidism, erectile dysfunction and absence of ejaculation, anemia and osteoporosis as well as low serum concentrations of luteinizing hormone, follicle-stimulating hormone and testosterone in combination with hyposmia.

Diabetic lipoproteins and adrenal aldosterone synthesis--a possible pathophysiological link?

An increased prevalence of diabetes mellitus (DM) has been reported in patients with primary aldosteronism (PA). DM is associated with abnormal structure and metabolism of circulating lipoproteins, which normally serve as a major source of cholesterol for adrenocortical steroidogenesis. The present study has been designed to investigate the effect of diabetically modified lipoproteins on adrenocortical aldosterone synthesis. Lipoproteins (VLDL, LDL, HDL) isolated from healthy volunteers, were subjected to oxidation or glycoxidation in the presence of sodium hypochlorite (3 mmol/l) or glucose (200 mmol/l), and aldosterone synthesis in human adrenocortical cells (H295R) was examined. Native and glycoxidized VLDL had greatest stimulatory effect on aldosterone production by 15-fold and 14-fold, respectively. At the molecular level, these VLDL produced maximum increases in Cyp11B2 mRNA level up to 17-fold. Experiments with the highly selective scavenger receptor class B type I (SR-BI) inhibitor BLT-1 revealed that cholesterol uptake from native and glycoxidized HDL and VLDL for hormone production is considerably mediated by SR-BI. Western blot analysis of extracellular signal-regulated kinase (ERK 1/2) phosphorylation and experiments with the MEK inhibitor U0126 indicated a specific mechanistic role of the ERK cascade in lipoprotein-mediated steroid hormone release. In summary, diabetic dyslipidemia and modification of circulating lipoproteins may promote adrenocortical aldosterone synthesis.

Hypercortisolism caused by ritonavir associated inhibition of CYP 3A4 under inhalative glucocorticoid therapy. 2 case reports and a review of the literature

Recent in vitro and in vivo studies have shown a potent inhibition of cytochrome P450 CYP3A4 through human immune deficiency virus (HIV) protease inhibitors (PIs). The PI ritonavir is described as the most potent compound within these CYP3A4 inhibitors. We present 2 cases who developed the sequelae of glucocorticoid excess following ritonavir therapy and inhalative glucocorticoid treatment: A 60-year-old HIV positive man developed the typical symptoms of Cushing's syndrome and a 52-year-old HIV positive man developed severe osteoporosis.

The effects of the endothelium on adrenal steroidogenesis and growth are mainly mediated by proteins other than endothelin-1

The endothelium releases factors stimulating the adrenal cortex. It is also known that endothelin-1 (ET-1) promotes generation of cortisol and aldosterone, and proliferation of adrenocortical cells. The aim of the study was to find out whether the effect of the endothelium on adrenocortical cells is dominated by the action of ET-1. The effects of endothelial cell-conditioned medium (ECCM), obtained during growth of human umbilical cord vein endothelial cells, on aldosterone and cortisol release by cells of the adrenocortical cancer cell-line NCI-H295R and the promoter activity of steroidogenic acute-regulatory protein (StAR) were studied. The effect of ECCM on proliferation of human primary normal adrenocortical and NCI-H295R cells was also investigated. Concentration-dependent increases in cortisol release that reached 192.7 ± 62.8 in percent of basal secretion, in aldosterone release that reached 188.2 ± 52.3 in percent of basal secretion, and in proliferation after stimulation with ECCM at concentrations of 10-50% were found. ECCM significantly activated the StAR promoter 3-fold in NCI-H295R cells if the ECCM was not pretreated with pronase. These effects of the endothelium were not reversed after co-incubation with endothelin receptor antagonists and could not be mimicked by incubation with endothelin-1. In conclusion, the cultured endothelial cells secrete a protein that stimulates steroidogenesis in adrenal cells and their growth. It was also shown that the ET-1 does not mediate the effect of ECCM on the NCI-H295R cell line.

Reproducibility of Elecsys anti-TSHR test results in a lot-to-lot comparison

Most recently, a new rapid and fully-automated TSH receptor autoantibody (TRAb) assay has been established. This assay system uses the M22 human monoclonal antibody for competing against the patient's TSH receptor autoantibodies (TRAb) to be detected. The aim of our present study was to compare the reproducibility of TRAb values based on measurements with different TSH receptor preparations in a lot-to-lot comparison. For TRAb values > 2 IU/l the relative differences ranged from -9.0 to +10.0%. The mean difference was 0.28 +/- 8%. For TRAb values around the cutoff for positivity (1.75 IU/l) a higher range of relative differences from -20 up to +15% was obtained. The overall mean of differences was -0.8+/-14%. The data clearly demonstrate that the automated TRAb assay has a high stability in regard to TSH receptor preparations.

Role of the novel mTOR inhibitor RAD001 (everolimus) in anaplastic thyroid cancer

Activation of the phosphatidylinositol-3-kinase (PI3K) signaling cascade is increasingly recognized as a common feature of thyroid follicular neoplasms. Among the PI3K downstream effectors, the main kinase, directly responsible for the increased cell growth and proliferation, is called mammalian target of rapamycin (mTOR). This central kinase might be directly inhibited via rapamycin and its derivatives. The aim of the present study was to examine whether RAD001 (everolimus) can selectively suppress the proliferation of different anaplastic thyroid cancer (ATC) cells. Five different human ATC cell lines were exposed to different concentrations of RAD001. Importantly, we found a dose-dependent growth inhibition in two ATC cell lines at concentrations of 43.5 and 94.5 nM although not as intensive as within the RAD001 responding K562cell line. The other cell lines revealed a GI (50) between 168 to 234 nM. In parallel, quantitative PCR of PCNA displayed a reduced expression of PCNA within the responding cell lines, respectively. In summary, we found a good responding effect in a part of ATC cell lines, which may have a clinical impact.

Adrenal cortical tumors and multiple endocrine neoplasia-related syndromes

Relatively frequent, adrenal masses include a multitude of different tumor types: uni- or bilateral hyperplasias, adenomas, and the rare entity of adrenocortical carcinomas. With significant progress in our appreciation of their underlying molecular pathomechanisms and from analysis of affected individuals and their families, a number of inherited diseases and tumor syndromes have been linked to adrenocortical tumorigenesis. These syndromes and diseases include the Carney complex, the McCune-Albright syndrome, multiple endocrine neoplasia type 1, familial adenomatosis coli, congenital adrenal hyperplasia, familial forms of primary aldosteronism, the Beckwith-Wiedemann syndrome, and the Li-Fraumeni syndrome. The key to successful management of these syndromes is identification of patients harboring adrenal tumors within the context of hereditary diseases, since diagnostic procedures, therapy and follow-up may significantly differ from the management of sporadic, isolated adrenal tumors. This review explores the underlying genetic defects, diagnosis and therapy of the major heritable tumor syndromes associated with adrenocortical tumorigenesis.

Stathmin as a marker for malignancy in pheochromocytomas

Pheochromocytomas of the adrenal medulla may be life-threatening catecholamine-producing tumors which are malignant in about 10% of cases. Differential diagnosis between malignant and benign tumors is dependent on the development of metastasis or extensive local invasion. A number of genetic aberrations have been described in pheochromocytomas, but no marker associated to malignancy has been reported. We applied an expression microarray containing 7770 cDNA clones and analysed the expression profiles in eleven tumors compared to normal adrenal medulla. Stathmin (STMN1, Op18) was most conspiciously overexpressed among the differentially expressed genes. RT-PCR analysis further confirmed mRNA overexpression, 6 to 8-fold for benign and malignant tumors, and 16-fold for metastases. Stathmin protein overexpression was observed by immunohistochemistry, and distinct differential protein expression between benign and malignant/metastasis specimens was confirmed by Western blot analysis. The results introduce stathmin as a possible diagnostic marker for malignant pheochromocytomas, and further evaluations are warranted.

Nestin as a marker in the classification of adrenocortical tumors

Expression of the intermediate filament, nestin, was long believed to be restricted to neuroectodermal stem cells. However, nestin expression has recently been detected in several tumors. Since adrenocortical carcinoma, a tumor entity still very difficult to classify, may gain the ability to aberrantly express neuroectodermal proteins including chromogranin A and synaptophysin, we asked the question whether nestin might also be detected in adrenocortical carcinomas, and if so, whether it might serve as a tool for clinical pathology. Therefore, we studied the expression of nestin in normal adrenal glands, adrenocortical adenomas, and adrenocortical cancers using specific immunohistochemistry and semi-quantitative reverse transcriptase-polymerase chain reaction. Immunostaining was nestin-positive in 1 out of 9 normal adrenal glands (11%), 2 out of 20 adrenocortical adenomas (10%), and 13 out of 16 adrenocortical carcinomas (81%). Expression of nestin mRNA could be detected in all microdissected tissues, independently of their grade of dedifferentiation. We conclude that our findings provide further evidence that nestin, as a marker, is not restricted to neuronal stem cells and nestin expression is worth to be studied in adrenocortical tumors.

The serum sodium to urinary sodium to (serum potassium)2 to urinary potassium (SUSPPUP) ratio in patients with primary aldosteronism

BACKGROUND

The aldosterone-to-renin ratio (ARR) is an established diagnostic tool in the screening for primary aldosteronism (PA). However, hormonal determinations are time consuming and expensive. Therefore, we studied the effectiveness of the serum sodium to urinary sodium to (serum potassium)(2) to urinary potassium (SUSPPUP) ratio in the diagnosis of PA.

DESIGN

This study included 35 patients with PA, 71 patients with essential hypertension to whom this diagnosis could be excluded, 23 normal subjects without hypertension, and 22 patients with primary adrenal insufficiency. We compared the SUSPPUP ratios with the ARR in these patient groups.

RESULTS

We show that the ARR distinguished PA from essential hypertension with a sensitivity of 94.2% and a specificity of 92.1% at a cutoff of 33 (ng L(-1): ng L(-1)). It correlated well with the SUSPPUP ratio. The sensitivity and specificity of SUSPPUP was 88.6% and 85.9% at a cutoff of 5.3 (mmol L(-1))(-1), respectively, and thus not as good as the ARR.

CONCLUSIONS

The ARR is a good parameter in the screening for PA. The SUSPPUP ratio is a cheap and rapid tool to assess the extent of mineralocorticoid excess and, therefore, can be offered to more patients. In addition, the application of the SUSPPUP ratio can be extended to patients who suffer from other forms of mineralocorticoid hypertension (e.g. with low aldosterone levels).

New mechanisms to control aldosterone synthesis

Arterial hypertension is a frequent and leading cardiovascular risk factor, and primary aldosteronism is a well-recognized cause of secondary hypertension. Aldosterone is the basic regulator of extracellular fluid volume and electrolyte balance. Alterations in plasma aldosterone levels significantly contribute to the development and the severity of hypertension. Adrenal steroidogenesis is controlled by two major feedback loops: the hypothalamic-pituitary-adrenal axis, which regulates cortisol synthesis, and the renin-angiotensin-aldosterone system, which directs aldosterone production. In addition to angiotensin, potassium, and corticotropin-which belong to the classic stimulators of aldosterone-neuropeptides, catecholamines, and prostaglandins are also known to stimulate aldosterone synthesis. Recently, several new mechanisms have been characterized that control the release of aldosterone by adrenocortical cells, among them endothelial cell-derived factors and adipokines. Further identification and characterization of these factors may help in the development of novel therapies for the treatment of arterial hypertension, various metabolic diseases, and other disorders.

Circulating chemokines in patients with autoimmune thyroid diseases

Chemokines are a group of small proteins that recruit different leukocyte subtypes to sites of inflammation and play important roles in initiating and maintaining immunological responses in autoimmune endocrine diseases including Graves' disease (GD) and Hashimoto's thyroiditis (HT). Previous studies have found increased gene and protein expression of different kinds of chemokines not only within the thyroid gland but also within thyroid cells in GD or HT patients. A few studies have determined serum levels of chemokines, with conflicting results. We measured circulating concentrations of CCL2, CCL5, CXCL9, and CXCL10 in patients with GD, HT, and nontoxic nodular thyroid disease (NNT). While CCL2 and CXCL9 concentrations were comparable in patients with either AITD or NNT, CCL5 was significantly increased in GD patients compared with HT or NNT subjects. In contrast, CXCL10 levels were lower in patients with GD, but the difference was statistically significant only when compared with patients with HT (p=0.0018). Importantly, GD patients who relapsed or went into remission had significantly different levels of CXCL9 (p=0.0252). Serum levels of CCL2, CCL5, CXCL9, and CXCL10 did not reveal any correlation with thyroid volume; with the levels of thyrotropin (TSH), FT3, or FT4; or with the titers of TSH receptor antibody and thyroperoxidase antibody. These data suggest that the expression patterns of chemokines in various thyroid diseases differ from each other, which may reflect the distinct immune responses in HT and GD.

Spontaneous remission of primary hyperparathyroidism

The diagnosis of primary hyperparathyroidism (pHPT) is characterized by the constellation of elevated plasma serum calcium levels and low serum anorganic phosphate associated with inadequately high blood concentrations of parathyroid hormone (PTH). Parathyroid adenomas are the main reason for this disorder and can frequently be detected by ultrasound examination. Surgical removal of the parathyroid adenoma is recommended in the case of primary hyperparathyroidism complicated by osteoporosis, hyper-calciuria, nephrolithiasis, or impaired renal function. Here we present the case of a 68-year-old man with spontaneous remission of primary hyperparathyroidism two years after the diagnosis was established. The remission was documented by laboratory findings (normalisation of serum calcium and PTH levels) and by ultrasound examination that showed the disappearance of a cervical mass suggesting a parathyroid adenoma.

[Adrenal gland tumors]

Adrenal masses are one of the most common tumors in humans. They are a very heterogenous group of diseases and include benign and malignant adrenocortical lesions, metastases, pheochromocytomas and other entities. Adrenal masses originating from steroidogenic or chromaffin cells may be silent or the source of subclinical or overt hormone excess, such as primary aldosteronism, hypercortisolism or symptomatic catecholamine excess. On the other hand, adrenal hyperplasia may be the result of excess ACTH secretion in steroid biosynthesis disorders with deficient glucocorticoid secretion, in glucocorticoid resistance, in Cushing's disease, or ectopic ACTH syndrome. Algorithms for endocrine testing, imaging studies and their combination are available for defining the tumor entity and for the characterization of the hormone excess syndromes. Recent developments in molecular biology have provided tools for testing for hereditary tumor syndromes associated with adrenal tumorigenesis and to establish strategies for further treatment and follow-up.

Adipocyte-derived products induce the transcription of the StAR promoter and stimulate aldosterone and cortisol secretion from adrenocortical cells through the Wnt-signaling pathway

CONTEXT

Obesity is associated with hypersecretion of cortisol and aldosterone and a high prevalence of arterial hypertension. At the cellular level, a direct effect of adipocytes on the expression of the steroidogenic acute regulatory (StAR) protein, a regulator of cortisol and aldosterone synthesis, and on aldosterone and cortisol secretion has been shown. However, the molecular mechanisms mediating this effect are not known.

OBJECTIVE

Wnt-signaling molecules are secreted by adipocytes and regulate the activity of SF-1, a key transcription factor in adrenal steroidogenesis. Therefore, we investigated whether adipocytes stimulate adrenal steroidogenesis through the activation of Wnt-signaling.

RESULTS

Using immunohistochemistry, we detected the expression of frizzled and beta-catenin in the adult human adrenal cortex. Transient transfection of a Wnt-dependent reporter-gene into adrenal NCI-H295R cells showed an induction of Wnt-mediated transcription to 308% after treatment with human fat cell-conditioned medium (FCCM). This finding was paralleled by an induction of StAR promoter activity (420%) by FCCM. The induction of StAR promoter activity by FCCM was inhibited by 49% when Wnt-signaling was blocked by the soluble Wnt-antagonist secreted Frizzled-Related-Protein-1 (sFRP-1). Overexpression of a constitutively active mutant of beta-catenin induced the transcription of the StAR promoter (440%). beta-Catenin and FCCM induced SF-1-mediated transcription at a SF-1-driven reporter gene (420 and 402%, respectively). Furthermore, the secretion of aldosterone and cortisol by NCI-H295R cells induced by FCCM was significantly inhibited by the Wnt-antagonist sFRP-1.

CONCLUSION

These data indicate that the Wnt-signaling pathway is one of the mechanisms mediating the effects of fat cells on adrenal StAR transcription and aldosterone and cortisol secretion.

Improved prediction of relapse of Graves' thyrotoxicosis by combined determination of TSH receptor and thyroperoxidase antibodies

BACKGROUND

Recently, we and others have demonstrated that high levels of auto-antibodies to the human TSH-receptor (TRAb) predict relapse of hyperthyroidism in Graves' disease (GD). Our objective was to extend the outcome of the prediction by combining TRAb with thyroperoxidase antibody (TPO-Ab) measurement.

PATIENTS AND METHODS

One hundred and thirty-one GD patients (118 females, 13 males) were analysed, of whom 94 patients (71.8%) had relapse, whereas 37 (28.2%) went into remission. Second generation TRAb and TPO-Ab assays were performed in GD patients with relapse and remission in mean 4.3 months after initial diagnosis.

RESULTS

The mean anti-TPO-Ab levels were similar in all patients with relapse and remission. However, there was a steady decline from 4047 U/ml to 530 U/ml in the remission group that correlated positively with TRAb values (>2 to >10 IU/l). The relapse group remained at consistently high levels. The positive predictive value (PPV) for relapse in patients with TRAbs >6 IU/l and anti-TPO-Abs >5000 U/ml was 100, whereas TRAbs >6 IU/l and anti-TPO-Abs >500 U/ml were associated with a PPV of 93.7 up to 96 (p=0.008). These Ab constellations accounted for about one third of all GD patients. For patients with TRAbs between >2 and <6 IU/l the PPV was 66.7-90.0.

CONCLUSION

Our follow-up analysis indicates that the prediction of relapse of GD can be improved by a combined measurement of TRAb and TPO-Ab. In patients with moderately increased Abs, determined about 6 months after initial diagnosis, an ablative therapy can be approached without delay.

Vascular-adrenal niche--endothelial cell-mediated sensitization of human adrenocortical cells to angiotensin II

Alterations in both vasculature and renin-angiotensin-aldosterone system are a consistent finding in the metabolic syndrome. Adrenal tissue is highly vascularized and encounters blood flow, exceeding by far the volume expected for its size. Endothelial cells in the adrenal vasculature are therefore a major cellular component of adrenocortical tissue. The aim of the study was to analyze the cellular interaction between endothelial and steroid producing cells, focusing on endothelial cell-factor-mediated activation of aldosterone synthesis. The interaction between human endothelial (HUVECs) cell-conditioned medium and human adrenocortical (NCI-H295R) cells IN VITRO induced a significant surge in aldosterone secretion. The endothelial cell-conditioned medium together with angiotensin II and forskolin also potentiated aldosterone release by 1.5-fold and 2.6-fold, respectively, while preincubation of NCI-H295R cells for 24 h with endothelial cell-conditioned medium enhanced and sensitized the response of NCI-H295R to subsequent angiotensin II and forskolin stimuli by 2.5-fold and 2.2-fold, respectively. The increase in aldosterone release after preincubation with endothelial cell-conditioned medium was sensitive to cycloheximide and KN-93. Cellular conditioning with endothelial-cell factors exerts a hitherto unknown paracrine regulation of aldosterone production in human adrenocortical cells. This interaction may contribute to altered basal aldosterone release and have a role in patients with hypertension.