Effect of KCNJ5 mutations on gene expression in aldosterone-producing adenomas and adrenocortical cells

CONTEXT

Primary aldosteronism is a heterogeneous disease that includes both sporadic and familial forms. A point mutation in the KCNJ5 gene is responsible for familial hyperaldosteronism type III. Somatic mutations in KCNJ5 also occur in sporadic aldosterone producing adenomas (APA).

OBJECTIVE

The objective of the study was to define the effect of the KCNJ5 mutations on gene expression and aldosterone production using APA tissue and human adrenocortical cells.

METHODS

A microarray analysis was used to compare the transcriptome profiles of female-derived APA samples with and without KCNJ5 mutations and HAC15 adrenal cells overexpressing either mutated or wild-type KCNJ5. Real-time PCR validated a set of differentially expressed genes. Immunohistochemical staining localized the KCNJ5 expression in normal adrenals and APA.

RESULTS

We report a 38% (18 of 47) prevalence of KCNJ5 mutations in APA. KCNJ5 immunostaining was highest in the zona glomerulosa of NA and heterogeneous in APA tissue, and KCNJ5 mRNA was 4-fold higher in APA compared with normal adrenals (P < 0.05). APA with and without KCNJ5 mutations displayed slightly different gene expression patterns, notably the aldosterone synthase gene (CYP11B2) was more highly expressed in APA with KCNJ5 mutations. Overexpression of KCNJ5 mutations in HAC15 increased aldosterone production and altered expression of 36 genes by greater than 2.5-fold (P < 0.05). Real-time PCR confirmed increases in CYP11B2 and its transcriptional regulator, NR4A2.

CONCLUSIONS

KCNJ5 mutations are prevalent in APA, and our data suggest that these mutations increase expression of CYP11B2 and NR4A2, thus increasing aldosterone production.

Combination chemotherapy in advanced adrenocortical carcinoma

BACKGROUND

Adrenocortical carcinoma is a rare cancer that has a poor response to cytotoxic treatment.

METHODS

We randomly assigned 304 patients with advanced adrenocortical carcinoma to receive mitotane plus either a combination of etoposide (100 mg per square meter of body-surface area on days 2 to 4), doxorubicin (40 mg per square meter on day 1), and cisplatin (40 mg per square meter on days 3 and 4) (EDP) every 4 weeks or streptozocin (streptozotocin) (1 g on days 1 to 5 in cycle 1; 2 g on day 1 in subsequent cycles) every 3 weeks. Patients with disease progression received the alternative regimen as second-line therapy. The primary end point was overall survival.

RESULTS

For first-line therapy, patients in the EDP-mitotane group had a significantly higher response rate than those in the streptozocin-mitotane group (23.2% vs. 9.2%, P<0.001) and longer median progression-free survival (5.0 months vs. 2.1 months; hazard ratio, 0.55; 95% confidence interval [CI], 0.43 to 0.69; P<0.001); there was no significant between-group difference in overall survival (14.8 months and 12.0 months, respectively; hazard ratio, 0.79; 95% CI, 0.61 to 1.02; P=0.07). Among the 185 patients who received the alternative regimen as second-line therapy, the median duration of progression-free survival was 5.6 months in the EDP-mitotane group and 2.2 months in the streptozocin-mitotane group. Patients who did not receive the alternative second-line therapy had better overall survival with first-line EDP plus mitotane (17.1 month) than with streptozocin plus mitotane (4.7 months). Rates of serious adverse events did not differ significantly between treatments.

CONCLUSIONS

Rates of response and progression-free survival were significantly better with EDP plus mitotane than with streptozocin plus mitotane as first-line therapy, with similar rates of toxic events, although there was no significant difference in overall survival. (Funded by the Swedish Research Council and others; FIRM-ACT ClinicalTrials.gov number, NCT00094497.).

Fine-needle aspiration cytology of adrenal masses: a re-assessment with histological confirmation

BACKGROUND

Fine-needle aspiration (FNA) of adrenal masses is a method currently indicated in lesions suspected of being extra-adrenal in origin; even though its diagnostic reliability has already been determined in many studies, few have used histological examination obtained after adrenalectomy for diagnostic confirmation.

AIM

To analyze the diagnostic performance of adrenal FNA in subjects with an available histological confirmation.

SUBJECTS AND METHODS

Fifty subjects (26 benign adrenal lesions, 9 primary malignant lesions, and 15 metastatic lesions) who had undergone ultrasound (US)-guided adrenal FNA and then adrenalectomy were re-analyzed retrospectively.

RESULTS

FNA guaranteed a sensitivity of 85.7% and a specificity of 100% in all subjects; after having divided the subjects into oncologic and non-oncologic groups, the sensitivity of the test in oncologic patients (100%) increased significantly compared to non-oncologic (57.1%) with no difference in specificity (100% in both groups). Considering also non-diagnostic samples in our analysis (no.=11; 22% of all samples studied), FNA correctly diagnosed malignancy only in 75% of the cases and benignancy only in 66.6%; however, even after including non-diagnostic samples, the percentage of correct malignancy diagnosis remained significantly higher in oncologic (93.3%) than in non-oncologic patients (44.4%) without significant statistical difference between the 2 groups regarding the percentage of correct benignancy diagnosis (respectively 100% and 63.6%).

CONCLUSIONS

Our study, based on histological confirmation, underlines the low discriminant value of US-guided adrenal FNA, though the method may have value in oncologic patients.

Effects of selenium supplementation on the natural course of autoimmune thyroiditis: a short review

Selenium (Se) is an important element that exerts its effects on the selenoproteins. It is an essential component of the glutathione peroxidase enzymes, which have anti-oxidant and anti-inflammatory properties, and a component of iodothyronine selenodeiodinases, which catalyze the extrathyroid production of T3 from T4. Se is important to several aspects of thyroid homeostasis and may influence the natural course of thyroid diseases such as autoimmune thyroiditis (AIT). This review analyzes the effects of Se supplementation in patients with AIT, based on the studies published on this issue to date.

Primary aldosteronism: the role of confirmatory tests

The high prevalence of primary aldosteronism among hypertensives justifies large scale screening by the aldosterone-renin ratio; however, this test is subject to several variables responsible for false-positive results. Functional tests to confirm autonomous aldosterone secretion are commonly used, with the fludrocortisone suppression test considered the gold standard, and saline infusion or captopril challenge, the most practical. However, each of these tests has sub-optimal sensitivity and specificity and none has been so far prospectively validated by comparing the results with the lateralization by adrenal vein sampling and the results of surgery. Their role in confirming the diagnosis of primary aldosteronism due to unilateral adenoma remains incompletely resolved.

Prevalence, Clinical, and Molecular Correlates of KCNJ5 Mutations in Primary Aldosteronism

Primary aldosteronism is the most common form of secondary hypertension. Mutations in the KCNJ5 gene have been described recently in aldosterone-producing adenomas (APAs). The aim of this study was to investigate the prevalence of KCNJ5 mutations in unselected patients with primary aldosteronism and their clinical, biological and molecular correlates. KCNJ5 sequencing was performed on somatic (APA, n=380) and peripheral (APA, n=344; bilateral adrenal hyperplasia, n=174) DNA of patients with primary aldosteronism, collected through the European Network for the Study of Adrenal Tumors. Transcriptome analysis was performed in 102 tumors. Somatic KCNJ5 mutations (p.Gly151Arg or p.Leu168Arg) were found in 34% (129 of 380) of APA. They were significantly more prevalent in females (49%) than males (19%; P <10 −3 ) and in younger patients (42.1±1.0 versus 47.6±0.7 years; P <10 −3 ) and were associated with higher preoperative aldosterone levels (455±26 versus 376±17 ng/L; P =0.012) but not with therapeutic outcome after surgery. Germline KCNJ5 mutations were found neither in patients with APA nor those with bilateral adrenal hyperplasia. Somatic KCNJ5 mutations were specific for APA, because they were not identified in 25 peritumoral adrenal tissues or 16 cortisol-producing adenomas. Hierarchical clustering of transcriptome profiles showed that APAs with p.Gly151Arg or p.Leu168Arg mutations were indistinguishable from tumors without KCNJ5 mutations. In conclusion, although a large proportion of sporadic APAs harbors somatic KCNJ5 mutations, germline mutations are not similarly causative for bilateral adrenal hyperplasia. KCNJ5 mutation carriers are more likely to be females; younger age and higher aldosterone levels at diagnosis suggest that KCNJ5 mutations may be associated with a more florid phenotype of primary aldosteronism.

Urine steroid metabolomics as a biomarker tool for detecting malignancy in adrenal tumors

CONTEXT

Adrenal tumors have a prevalence of around 2% in the general population. Adrenocortical carcinoma (ACC) is rare but accounts for 2-11% of incidentally discovered adrenal masses. Differentiating ACC from adrenocortical adenoma (ACA) represents a diagnostic challenge in patients with adrenal incidentalomas, with tumor size, imaging, and even histology all providing unsatisfactory predictive values.

OBJECTIVE

Here we developed a novel steroid metabolomic approach, mass spectrometry-based steroid profiling followed by machine learning analysis, and examined its diagnostic value for the detection of adrenal malignancy.

DESIGN

Quantification of 32 distinct adrenal derived steroids was carried out by gas chromatography/mass spectrometry in 24-h urine samples from 102 ACA patients (age range 19-84 yr) and 45 ACC patients (20-80 yr). Underlying diagnosis was ascertained by histology and metastasis in ACC and by clinical follow-up [median duration 52 (range 26-201) months] without evidence of metastasis in ACA. Steroid excretion data were subjected to generalized matrix learning vector quantization (GMLVQ) to identify the most discriminative steroids.

RESULTS

Steroid profiling revealed a pattern of predominantly immature, early-stage steroidogenesis in ACC. GMLVQ analysis identified a subset of nine steroids that performed best in differentiating ACA from ACC. Receiver-operating characteristics analysis of GMLVQ results demonstrated sensitivity = specificity = 90% (area under the curve = 0.97) employing all 32 steroids and sensitivity = specificity = 88% (area under the curve = 0.96) when using only the nine most differentiating markers.

CONCLUSIONS

Urine steroid metabolomics is a novel, highly sensitive, and specific biomarker tool for discriminating benign from malignant adrenal tumors, with obvious promise for the diagnostic work-up of patients with adrenal incidentalomas.

BRAF(K601E) mutation in a patient with a follicular thyroid carcinoma

BACKGROUND

BRAF mutations, the most common genetic alteration associated with papillary thyroid carcinoma (PTC), have never been associated with follicular thyroid carcinoma (FTC) except for one possible case, which, however, had some cellular features of the follicular variant of PTC. Here, we present a patient with a BRAF mutation within a FTC.

SUMMARY

A 78-year-old man presented with a nodular lesion 8 cm in size in the right thyroid lobe, coexisting with a goiter. Fine-needle aspiration samples were obtained for cytology, immunocytology, and molecular analysis. Immunoblot analysis on thyroid tissues was performed to evaluate the most important tumor activating pathways. Cytology was consistent with "follicular neoplasia" (negative for galectin-3 immunostaining); molecular analysis on the cytology sample detected a K601E mutation in the exon 15 of the BRAF gene. After total thyroidectomy with lymph-node dissection, the diagnosis of FTC was established by histopathological examination. The BRAF(K601E) mutation was confirmed in DNA obtained from different areas of the FTC. In addition, an activating mutation (E545A) in the PKI3CA oncogene was found in the FTC. As expected, immunoblot analysis showed activation of the PI3K/Akt pathway.

CONCLUSION

This article describes what may be the first case of a classical FTC carrying a BRAF mutation. Unlike the most common BRAF mutation seen in PTC carcinoma (BRAF(V600E)), this patient's mutation was a BRAF(K601E) mutation that previously has been associated with some cases of the follicular variant of PTC. The BRAF(K601E) mutation should be included in the spectrum of genetic alterations in FTC.

Adrenal nodules in patients with Cushing's disease: prevalence, clinical significance and follow-up

Adrenal glands in Cushing's disease (CD) range from normal to showing diffuse enlargement in most cases. The finding of nodular lesions has been reported, but information about prevalence and evolution is described in few reports.

AIM

To investigate the prevalence of nodular adrenal glands in patients with CD and assess its evolution after disease remission.

SUBJECTS AND METHODS

We assessed 41 CD patients' abdominal computed tomography (CT) scans obtained during the active phase of the disease and evaluated the dynamics of ACTH and cortisol secretion. CT was repeated after disease remission in patients with adrenal nodules.

RESULTS

Fifteen of 41 patients had nodular and the remaining 26 had normal or enlarged adrenal glands. Patients with nodules were older (45.1 ± 8.8 vs 36.9 ± 12.7 yr; p=0.03) and had longer-standing disease (57.3 ± 56.9 vs 32.9 ± 29.1 months; p=0.05) than patients with normal/enlarged adrenal glands. ACTH (45.4 ± 21.3 vs 70.5 ± 39.1 pg/ml; p=0.04) and urinary free cortisol levels (606.1 ± 512.3 vs 301.0 ± 224.7 μg/day, p=0.01) were significantly lower in patients with adrenal nodules while there were no differences between the groups in terms of dynamic tests results. Post-operative follow-up showed regression or shrinkage of the nodules in 8 out of 10 patients in disease remission.

CONCLUSIONS

We found that adrenal nodular glands are a frequent finding in CD in particular in older patients and in those with a longerstanding disease. Nevertheless, a high percentage of nodules regression or shrinking was evidenced in our series after disease remission.

A clinical phenotype mimicking essential hypertension in a newly discovered family with Liddle's syndrome

BACKGROUND

Liddle's syndrome (LS) is a monogenic form of hypertension simulating a mineralocorticoid excess, and is currently suspected in young hypokalemic hypertensives. The aims of the study were: (i) to evaluate the clinical phenotype of LS in a newly identified Italian family of Sicilian origin carrying a gain-of-function mutation of the β subunit of the epithelial sodium channel (ENaC) (P617L) previously reported by our group in an apparently unrelated Sicilian patient presenting the typical phenotype of LS including hypokalemia; (ii) to determine whether an unknown biological relationship exists between the newly identified family and the family of the proband previously reported.

METHODS

Genetic analysis was performed in the present family, in the individual in which the βP617L mutation was first observed, and in his relatives.

RESULTS

βP617L mutation was identified in the proband and in three maternal relatives. None of them showed hypokalemia. Mild to severe early onset hypertension and left ventricular hypertrophy were present in all of them. Analysis of mitochondrial DNA (mtDNA) and Y chromosome profiles in the present family and in the proband's family previously reported showed the absence of a relationship between them. The availability of only one carrier of the mutation in one of the two families meant that a genetic analysis able to assess a founder effect was not feasible.

CONCLUSIONS

LS should be considered in all cases of early onset hypertension, independently of the plasma potassium concentration. The incidence of LS may be greater than is currently thought, because hypokalemia is not invariably present.

The glucose-dependent insulinotropic polypeptide receptor is overexpressed amongst GNAS1 mutation-negative somatotropinomas and drives growth hormone (GH)-promoter activity in GH3 cells

Somatic mutations in the GNAS1 gene, encoding the α-subunit of the heterotrimeric stimulatory G protein (Gαs), occur in approximately 40% of growth hormone (GH)-secreting pituitary tumours. By altering the adenylate cyclase-cAMP-protein kinase A pathway, they unequivocally give somatotroph cells a growth advantage. Hence, the pathogenesis of somatotropinomas could be linked to anomalies in receptors coupled to the cAMP second-messenger cascade. Among them, the glucose-dependent insulinotropic polypeptide receptor (GIPR) is already known to play a primary role in the impaired cAMP-dependent cortisol secretion in patients affected by food-dependent Cushing's syndrome. In the present study, 43 somatotropinomas and 12 normal pituitary glands were investigated for GIPR expression by quantitative reverse transcriptase-polymerase chain reaction, western blotting and immunohistochemistry. Tumoural specimens were also evaluated for GNAS1 mutational status. The effect of GIPR overexpression on cAMP levels and GH transcription was evaluated in an in vitro model of somatotropinomas, the GH-secreting pituitary cell line GH3. GIPR was expressed at higher levels compared to normal pituitaries in 13 GNAS1 mutation-negative somatotropinomas. GIP stimulated adenylyl cyclase and GH-promoter activity in GIPR-transfected GH3 cells, confirming a correct coupling of GIPR to Gαs. In a proportion of acromegalic patients, GIPR overexpression appeared to be associated with a paradoxical increase in GH after an oral glucose tolerance test. Whether GIPR overexpression in acromegalic patients may be associated with this paradoxical response or more generally involved in the pathogenesis of acromegaly, as suggested by the mutually exclusive high GIPR levels and GNAS1 mutations, remains an open question.

Combined RET and Ki-67 assessment in sporadic medullary thyroid carcinoma: a useful tool for patient risk stratification

OBJECTIVE

Medullary thyroid carcinoma (MTC) derives from the parafollicular C cells, being sporadic in 75% of cases and familial in 25%, due to RET proto-oncogene germinal mutations. In sporadic forms, stage at diagnosis is the most important negative prognostic factor. The aim of this study was to evaluate the prognostic impact of molecular and immunohistochemical markers in sporadic MTC.

DESIGN AND METHODS

We studied 60 patients with sporadic MTC. For each case, we sought RET somatic mutations in the primary cancer and in lymph node metastases. The primary cancer also underwent immunohistochemical examination for Ki-67.

RESULTS

A somatic RET mutation was found in 38% of patients, being M918T in 52% of them. We observed a statistically significant association between RET mutations and male gender (P<0.01), tumor size (P<0.05), lymph nodes (P<0.05) and distant metastases (P<0.001), advanced stage (P<0.05), increased risk of persistent disease (P=0.01), and low overall survival (P<0.01). High Ki-67 levels were similarly associated with extra-thyroid spread (P<0.05), lymph nodes (P<0.05) and distant metastases (P<0.001), advanced stage (P=0.01), and low overall survival (P=0.01). Combining somatic RET analysis with Ki-67 assessment seems to be useful for increasing the specificity of Ki-67 assessment alone and identifying patients with a more aggressive cancer: in our series, only the patients who died during the follow-up had both a somatic RET mutation and a Ki-67 expression level >50 cells/mm(2).

CONCLUSIONS

The combined evaluation of RET and Ki-67 could act as an adjuvant prognostic marker useful for ameliorating the initial risk stratification of patients with sporadic MTC.

AME position statement on adrenal incidentaloma

OBJECTIVE

To assess currently available evidence on adrenal incidentaloma and provide recommendations for clinical practice.

DESIGN

A panel of experts (appointed by the Italian Association of Clinical Endocrinologists (AME)) appraised the methodological quality of the relevant studies, summarized their results, and discussed the evidence reports to find consensus.

RADIOLOGICAL ASSESSMENT

Unenhanced computed tomography (CT) is recommended as the initial test with the use of an attenuation value of ≤10 Hounsfield units (HU) to differentiate between adenomas and non-adenomas. For tumors with a higher baseline attenuation value, we suggest considering delayed contrast-enhanced CT studies. Positron emission tomography (PET) or PET/CT should be considered when CT is inconclusive, whereas fine needle aspiration biopsy may be used only in selected cases suspicious of metastases (after biochemical exclusion of pheochromocytoma). HORMONAL ASSESSMENT: Pheochromocytoma and excessive overt cortisol should be ruled out in all patients, whereas primary aldosteronism has to be considered in hypertensive and/or hypokalemic patients. The 1 mg overnight dexamethasone suppression test is the test recommended for screening of subclinical Cushing's syndrome (SCS) with a threshold at 138 nmol/l for considering this condition. A value of 50 nmol/l virtually excludes SCS with an area of uncertainty between 50 and 138 nmol/l.

MANAGEMENT

Surgery is recommended for masses with suspicious radiological aspects and masses causing overt catecholamine or steroid excess. Data are insufficient to make firm recommendations for or against surgery in patients with SCS. However, adrenalectomy may be considered when an adequate medical therapy does not reach the treatment goals of associated diseases potentially linked to hypercortisolism.

Somatostatin receptor expression in adrenocortical tumors and effect of a new somatostatin analog SOM230 on hormone secretion in vitro and in ex vivo adrenal cells

BACKGROUND

Somatostatin is a widely distributed polypeptide that modulates endocrine and exocrine secretion, cell proliferation, and apoptosis by 5 somatostatin receptors (SSTR1-5). The inhibitory effects of somatostatin on tumor growth may be the result of its suppressing the synthesis and/or secretion of growth factors and growth-promoting hormones.

AIM

Very little information is available on the effect of somatostatin analogs on adrenal tumors, so we examined SSTR expression in adrenocortical tumors and studied the effect of a somatostatin analog (SOM230) on hormone secretion and cell viability in adrenal cells.

MATERIAL/SUBJECTS AND METHODS

SSTR expression was analyzed by real-time PCR in 13 adrenocortical carcinomas (ACC), 24 aldosterone-producing adenomas (APA), 11 cortisol-producing adenomas (CPA), and 7 normal adrenals (NA), and verified by immunohistochemistry (IHC) in 14 samples. The effect of SOM230 on cortisol or aldosterone secretion in H295R and primary cell cultures was determined by radioimmunoassay, and its effect on viability in H295R and SW13 using the MTT test.

RESULTS

SSTR1 and SSTR2 mRNA was expressed in 100% of adrenal tumors. Compared to NA, ACC revealed an increase in almost all SSTR, while only some APA over-expressed SSTR3 and SSTR1. CPA expressed SSTR similar to NA. IHC confirmed the mRNA expression data. At nanomolar concentrations, SOM230 inhibited hormone secretion in primary adrenal cultures and H295R cells, but had no evident effect on cell viability.

CONCLUSIONS

The evidence of SSTR over-expression (particularly in ACC) and of hormone secretion being inhibited by SOM230 suggests a potential therapeutic role for this broad-spectrum somatostatin analog in adrenal tumors.

Increased rate of intracranial saccular aneurysms in acromegaly: an MR angiography study and review of the literature

BACKGROUND

The concurrence of intracranial aneurysms and acromegaly has been reported and debated previously. Our study in a large number of patients aimed to verify whether acromegaly patients carry a higher risk of harboring intracranial saccular aneurysms and to evaluate the possible relationship using clinical, laboratory, and imaging techniques.

MATERIALS AND METHODS

A total of 152 of 161 consecutive acromegaly patients (median age, 55.7 yr; 82 females) underwent neuroimaging evaluation of the circle of Willis. Clinical data (disease duration and disease control, hypertension, smoking history, diabetes and dyslipidemia, previous surgery or radiotherapy, previous or current pharmacological therapy), laboratory findings (GH and IGF-I at onset and shortly before examination), and pituitary adenoma imaging features (size and invasiveness of the cavernous sinus) were recorded.

RESULTS

Twenty-six patients (17.3%) harbored 40 newly diagnosed intracranial aneurysms; two other patients had previously undergone aneurysm clipping due to subarachnoid hemorrhage. Ten patients had multiple aneurysms; most of the aneurysms were located in the intracranial tract of the internal carotid artery (67.5%); no aneurysms belonged to the vertebrobasilar circulation. The presence of intracranial aneurysms correlated with GH serum values at disease onset (P < 0.05) and showed a trend to a positive correlation with poor disease control (P = 0.06); no other laboratory, clinical, and radiological findings correlated with the presence of intracranial aneurysms.

CONCLUSIONS

GH serum excess seems to carry an increased risk of developing intracranial aneurysms. A neuroradiological evaluation of the intracranial circulation might therefore be considered in the diagnostic work-up of patients affected with acromegaly.

Adrenal lesions in acromegaly: do metabolic aspects and aryl hydrocarbon receptor interacting protein gene have a role? Evaluation at baseline and after long-term follow-up

BACKGROUND

Adrenal lesions are discovered in acromegaly more frequently than in general population, without relationship with primary disease. Some patients, carriers of aryl hydrocarbon receptor interacting protein (AIP) gene mutations, developed an adrenal neoplasm.

AIM

To evaluate the role of metabolic and genetic aspects and the follow-up of adrenal nodules in acromegaly.

MATERIAL AND METHODS

We studied 69 acromegalic patients (30 male and 39 female, 56 ± 15 yr) who had been referred to the Endocrinology Unit of Padua. In all patients we determined body mass index (BMI) and waist-to-hip ratio (WHR); we performed an oral glucose tolerance test (OGTT) whenever possible. If adrenal computed tomography revealed a lesion, the patient underwent an endocrine and genetic study.

RESULTS

Adrenal lesions were identified in 14 patients and were not related to gender, duration of disease, GH or IGF-I concentrations, basal and after-OGTT glucose and insulin levels, log(HOMA-IR) and Quantitative Insulin Sensitivity Check Index (QUICKI) values, whereas BMI and WHR were higher in patients with adrenal lesions. Baseline endocrine and radiological study revealed benign lesions; during mean 4-yr follow-up none of the patients showed hormone excess, even though some lesions increased in size. We did not find any mutation in AIP gene, except heterozygous silent alteration (T48T).

CONCLUSIONS

The frequency of non-functioning adrenal lesions in acromegaly is not associated with the considered aspects, except BMI and WHR. The prolonged follow-up showed that these lesions have a tendency to increase in size independently of the control of acromegaly, so a morphological follow- up is recommended.

A case of primary aldosteronism in pregnancy: do LH and GNRH receptors have a potential role in regulating aldosterone secretion?

OBJECTIVE

The mechanisms inducing steroidogenesis in primary aldosteronism (PA) remain poorly defined. It was recently demonstrated that some G-protein-coupled receptors are abnormally expressed in aldosterone-producing adenomas (APA). We evaluated the potential role of LH and GNRH receptors (LHR (or LHCGR) and GNRHR) in regulating aldosterone secretion in a patient with APA arising during pregnancy (index case) and in a subset of other patients with PA.

PATIENTS AND METHODS

GNRH test was performed in the index case, 11 other PA, and 5 controls. GNRHR and LHR expressions were examined in 23 APA and 6 normal tissues.

RESULTS

Aldosterone response increased significantly (114%) in the index case after GNRH test was performed preoperatively, while it was blunted after adrenalectomy. Aldosterone also increased after human chorionic gonadotropin and triptorelin stimulation. A partial aldosterone response to GNRH was observed in other 7/11 PA, while a significant response was observed in two patients. Controls did not respond to GNRH test. GNRHR was overexpressed and LHR expression was moderate in the APA tissue from the index case. Moreover, LHR was found in normal adrenals and overexpressed in 6/22 APA. GNRHR was overexpressed in 6/22 APA, 2 of them with a 95- and 109-fold higher expression than normal. A correlation between the clinical and molecular findings was observed in five out of seven patients.

CONCLUSION

We describe a case of PA diagnosed during pregnancy, which appeared to correlate with aberrant LHR and GNRHR expression. Our findings suggest that a subset of patients with PA has aberrant LHR and GNRHR expression, which could modulate aldosterone secretion.

New insight into the hypercoagulability of Cushing's syndrome

BACKGROUND

Hypercoagulability and a tendency for thromboembolic complications are reported in Cushing's syndrome (CS). The hypercoagulability is due mainly to the cortisol-induced increase in von Willebrand factor (VWF) and factor VIII. This is not a constant feature of CS, however; it depends on particular single nucleotide polymorphism (SNP) haplotypes in the VWF gene promoter: haplotype 1 (-3268G/-2709C/-2661A/-2527G) confers a greater risk of VWF upregulation by cortisol than haplotype 2 (-3268C/ -2709T/-2661G/-2527A). In healthy individuals these SNPs are in linkage disequilibrium with the -2144 (GT)(n) of the VWF promoter: haplotype 1 mainly segregates with short GT repeats (15-19, GTs), haplotype 2 with long repeats (GT ≥ 20, GT(L)).

METHODS

We analyzed the (GT)(n) locus, the SNP haplotypes and their association with VWF levels in 80 CS patients in order to precisely define the cortisol-sensitive VWF promoter pattern. CS patients were divided into groups A (increased VWF) and B (normal VWF).

RESULTS

Haplotype 1 and (GT)(S) were more frequent in group A patients, and conferred a 9- and 7.5-fold risk of developing high VWF levels, respectively. Haplotype 2 and (GT)(L) were more represented in group B. There was also an unexpected higher prevalence of recombinant SNP haplotypes in CS patients (6.2%) than in normals (0.9%), p = 0.002.

CONCLUSIONS

Our results indicate that the cortisol-induced increase in VWF may be predicted by VWF promoter polymorphisms, haplotype 1 and (GT)(S) being the sensitive pattern. These represent new markers for defining the prothrombotic risk of CS. The clinical significance, if any, of the increased recombination rate in SNP haplotypes in the VWF promoter warrants further study.

The R304X mutation of the aryl hydrocarbon receptor interacting protein gene in familial isolated pituitary adenomas: Mutational hot-spot or founder effect?

BACKGROUND

Mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene have been described in about 15% of kindreds with familial isolated pituitary adenomas and in a minority of early onset sporadic pituitary adenomas (PA). Among the AIP mutations reported so far, the R304X (AIPR304X) represents, together with the "Finnish mutation" Q14X, the most common one.

METHODS

Three AIPR304X Italian families, including a newly reported kindred, have been genotyped for 12 genetic markers surrounding the AIP gene in order to look for a potential founder effect in Italy. Disease penetrance and genotype-phenotype correlations were also addressed.

RESULTS

Analysis of chromosome 11' genetic markers revealed a common haplotype in 2 AIPR304X kindreds originating from central Italy. Overall, 17 mutations carriers were identified, including 7 patients and 10 unaffected subjects, respectively, arguing in this case for a disease penetrance of 41%. Mean age at diagnosis was 19.1±6.7 yr old, with females tending to be older than males. Though most PA were somatotropinomas (6/7), a great variability in disease severity was observed, even between subjects sharing the same at-risk haplotype.

CONCLUSION

These data provide strong evidence for a new founder effect of the AIPR304X mutation in central Italy and the observed variations in disease severity point out the role of additional genetic or environmental factors in such kindreds.

Primary aldosteronism: what consensus for the diagnosis

Primary Aldosteronism (PA) is characterized by inappropriate aldosterone production partially autonomous of the renin-angiotensin system. Since the ARR ratio was introduced a much higher prevalence of this disease is recognized. PA could be the most common identifiable, specifically treatable and potentially curable form of hypertension so the need of a clinical practice guideline on primary aldosteronism becomes mandatory. Recently the Endocrine Society USA published clinical practice guidelines for the diagnosis and treatment of patients with primary hyperaldosteronism. Systematic reviews of available evidence were used to formulate the key treatment and prevention recommendations. Actually the Endocrine Society consensus is the most used guidelines in diagnosis and treatment of hyperaldosteronism. However, there remains a few unresolved issues, which unfortunately require more of a detour guide and cannot be easily addressed by a straight forward guideline.

Defects of steroidogenesis

In the biosynthesis of steroid hormones the neutral lipid cholesterol, a normal constituent of lipid bilayers is transformed via a series of hydroxylation, oxidation, and reduction steps into a vast array of biologically active compounds: mineralocorticoids, glucocorticoids, and sex hormones. Glucocorticoids regulate many aspects of metabolism and immune function, whereas mineralocorticoids help maintain blood volume and control renal excretion of electrolytes. Sex hormones are essential for sex differentiation in male and support reproduction. They include androgens, estrogens, and progestins. A block in the pathway of steroid biosynthesis leads to the lack of hormones downstream and accumulation of the upstream compounds that can activate other members of the steroid receptor family. This review deals with the clinical consequences of these blocks.

The Functional c.-2G>C Variant of the Mineralocorticoid Receptor Modulates Blood Pressure, Renin, and Aldosterone Levels

The mineralocorticoid receptor (MR) is essential in the regulation of volemia and blood pressure. Rare mutations in the MR gene cause type 1 pseudohypoaldosteronism and hypertension. In this study we characterized the common MR polymorphism c.-2G>C (rs2070951) in vitro and tested its influence on parameters related to blood pressure regulation and the renin-angiotensin system. In vitro studies showed that the G allele was associated with decreased MR protein levels and reduced transcriptional activation compared with the C allele. Association studies were performed with several outcome variables in 3 independent cohorts: a mild hypertensive group subjected to a salt-sensitivity test, a healthy normotensive group included in a crossover study to receive both a high and low Na/K diet, and a large cohort (The Netherlands Study of Depression and Anxiety), in which blood pressure was measured. Subjects with the GG genotype had significantly higher plasma renin levels both in the mild hypertensive group and in normal volunteers compared with homozygous C carriers. The GG genotype was also correlated with higher plasma aldosterone levels in healthy subjects. In both the mild hypertensive group and The Netherlands Study of Depression and Anxiety cohort the genotype GG was associated with higher systolic blood pressure in males. In conclusion, the G allele of the common functional genetic polymorphism c.-2G>C in the MR gene associates with increased activation of the renin-angiotensin-aldosterone axis and with increased blood pressure, probably related to decreased MR expression.

BRAF in primary and recurrent papillary thyroid cancers: the relationship with (131)I and 2-[(18)F]fluoro-2-deoxy-D-glucose uptake ability

OBJECTIVE

BRAF V600E is a potential marker of poor prognosis in papillary thyroid cancers (PTC). In a previous report, we showed that recurrent PTC with no radioiodine ((131)I) uptake are frequently associated with BRAF mutations, a low expression of thyroid-related genes and a high expression of glucose type-1 transporter gene.

AIM

The aim of the present study was to assess BRAF status in a large series of recurrent PTC patients, considering paired primary and recurrent cancers. The BRAF genotype was correlated with the ability to concentrate (131)I and/or 2-[(18)F]fluoro-2-deoxi-d-glucose ((18)F-FDG) in the recurrent cancers, serum markers of recurrence, and patient outcome.

DESIGN AND METHODS

We studied 50 PTC patients with recurrent cervical disease submitted to a re-intervention, followed up in median for 9 years. BRAF analysis was conducted by direct sequencing and mutant allele-specific PCR amplification. In 18 cases, molecular analysis was also assessed in the primary cancer. Out of 50 patients, 30 underwent (18)F-FDG-positron emission tomography-computed tomography.

RESULTS

BRAF V600E-positive recurrent patients were found (131)I-negative in 94% of cases (P<0.001); 73% of the cancers carrying BRAF V600E were both (131)I-negative and (18)F-FDG positive. In paired primary and recurrent PTC, BRAF V600E was observed in 79% of the primary cancers and 84% of their recurrences. Three patients with (131)I-negative and BRAF V600E-positive recurrent cancers deceased during follow-up.

CONCLUSIONS

BRAF mutations are more common in thyroid recurrences with no (131)I uptake than in (131)I-positive cases. They are correlated with the ability to concentrate (18)F-FDG, and they can appear, albeit rarely, as a de novo event in the course of PTC recurrences.

Influence of physiological dietary selenium supplementation on the natural course of autoimmune thyroiditis

OBJECTIVE

Our study aimed to investigate whether physiological doses of selenium (Se) influence the natural course of autoimmune thyroiditis (AIT).

DESIGN AND PATIENTS

A total of 76 consecutive patients (65 F, 11 M, median 43, range 15-75 years) with AIT, normal or slightly elevated TSH and fT4 within the normal range were divided into two groups: Group 0 (30 cases) was given no treatment while Group 1 (46 cases) was treated with sodium selenite 80 μg/day as a single oral dose for 12 months. Thyroperoxidase and thyroglobulin autoantibodies (TPO-Ab; Tg-Ab), TSH, fT4 and urine iodine concentrations (UIC) were measured at baseline and after 6 and 12 months of follow-up. Thyroid ultrasonography (US) was performed at each follow-up point. Echogenicity was measured by histographic analysis of gray-scale pixels (gsp) ranging from 0 = black to 255 = white.

RESULTS

Thyroid echogenicity decreased significantly in both groups after 6 months, but after 12 months, it had changed no more in Group 1, whereas it had dropped further in Group 0. No significant variation in TPO-Ab or Tg-Ab levels was observed between the two groups after 6 months, but both values decreased significantly after 12 months in Group 1, and five patients in this group became negative for TPO-Ab. TSH and FT4 showed no significant variations in either group.

CONCLUSIONS

Dietary supplementation with physiological doses of Se seems to be effective in preventing a reduction in thyroid echogenicity after 6 months of treatment and in reducing TPO-Ab and Tg-Ab after 12 months, but does not modify TSH or FT4.

Prevalence of AIP mutations in a large series of sporadic Italian acromegalic patients and evaluation of CDKN1B status in acromegalic patients with multiple endocrine neoplasia

BACKGROUND

Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene and the p27(KIP1) encoding gene CDKN1B have been associated with two well-defined hereditary conditions, familial isolated pituitary adenoma (FIPA) and multiple endocrine neoplasia type 4 (MEN4). Somatotropinomas are present in most AIP mutated FIPA kindreds, as well as in two-thirds of MEN4 patients who carry pituitary tumors.

METHODS

Germline DNA samples of 131 Italian sporadic acromegalic patients including 38 individuals with multiple tumors, and of six FIPA families (four homogeneous for prolactinomas and two heterogeneous with prolactin/nonfunctioning pituitary adenomas) were collected in a multicentric collaborative study. The prevalence of AIP and CDKN1B gene point mutations and copy number variations were evaluated.

RESULTS

Two novel (IVS3+1G>A and c.871G>A) and one previously described (c.911G>A) AIP mutations were detected in four apparently sporadic cases (3.1%) with relatively high age at diagnosis (49+/-18, range 30-67). No mutations/rearrangements were detected in FIPA families. The highly conserved c.871G>A substitution was detected in a patient who also carried a MEN1 mutation suggesting that she is a double heterozygote. The possible pathogenic effect on AIP splicing of the silent substitution c.144G>A found in another patient was ruled out using a minigene-based approach. CDKN1B mutations/rearrangements were neither identified in patients with multiple neoplasia nor in FIPA families.

CONCLUSION

AIP is mutated in about 3% of apparently sporadic acromegalic patients. The relatively high age at diagnosis, as well as its sporadic presentation, suggests that these patients are carriers of mutations with reduced pathogenicity. p27(KIP1) is unlikely to represent the common unifying nonendocrine etiology for acromegaly and cancer.

The role of TASK1 in aldosterone production and its expression in normal adrenal and aldosterone-producing adenomas

OBJECTIVES

Aldosterone production in the adrenal glomerulosa is mainly regulated by angiotensin II and K+. Adrenal glomerulosa cells are uniquely sensitive to extracellular K+. Genetic deletion of subunits of K+-selective leak-channels (KCNK), TASK1 and/or TASK3, in mice generates animals with hyperaldosteronism and histological changes in the adrenal cortex. Herein, we studied the expression of TASK1 in human adrenocortical cells, as well as its role in aldosterone production in H295R cells.

DESIGN

TASK1 expression was investigated by comparative microarray analysis of aldosterone-producing adenomas (APA) and normal adrenals (NAs). The effects of TASK1 knockdown by siRNA transfection were investigated in H295R cells. Fluo-4 fluorescent measurements of intracellular Ca2+ and pharmacological inhibition of Ca2+ -dependent calmodulin kinases (CaMK) were performed to better define the effects of TASK1 on Ca2+ signalling pathways.

RESULTS

Microarray analysis of APA and NA showed similar expression of TASK1 between these two groups. However, in APA, NA and H295R cells the expression of TASK1 was predominant when compared with other KCNK family members. Knockdown of TASK1 (with siRNA) induced the expression of steroidogenic acute regulatory (StAR) protein and aldosterone synthase (CYP11B2), and also stimulated pregnenolone and aldosterone production. Cells transfected with siTASK1 had increased intracellular Ca2+, leading to activation of CaMK and increased expression of CYP11B2.

CONCLUSIONS

Our study reveals the predominant expression of TASK1 over other KCNK family genes in the human adrenal cortex. Herein, we also described the role of TASK1 in the regulation of human aldosterone production through regulation of intracellular Ca2+ and CaMK signalling pathways.

Cytotoxic T lymphocyte antigen-4 Ala17 polymorphism is a genetic marker of autoimmune adrenal insufficiency: Italian association study and meta-analysis of European studies

OBJECTIVE

Cytotoxic T lymphocyte antigen-4 (CTLA4) gene polymorphism has been associated with human autoimmune diseases, but discordant data are available on its association with autoimmune Addison's disease (AAD). We tested the human leukocyte antigen (HLA)-independent association of CTLA4+49 (A/G) (Ala 17) and/or CTLA4 CT60 (A/G) polymorphism with AAD.

DESIGN

DNA samples from 180 AAD patients and 394 healthy control subjects from continental Italy were analyzed, and association statistical analyses and meta-analysis of published studies were performed. Methods TaqMan minor groove binder chemistry assays and PCR fragment length polymorphism assays were used.

RESULTS

Frequency of allele G of CTLA4+49 was significantly increased among AAD patients (40% alleles) than among healthy controls (27% alleles; P<0.0001). CTLA4 CT60 polymorphism was associated with AAD only in the heterozygous A/G individuals. The frequency of +49 AG+GG genotypes was significantly higher among AAD patients than among healthy control subjects, in both a co-dominant (P<0.0001) and G dominant model (P<0.0001). CTLA4+49 allele G was significantly associated with disease risk in both patients with isolated AAD and in patients with autoimmune polyendocrine syndrome. Multivariate logistic regression analysis showed that CTLA4+49 allele G was positively associated with AAD (P<0.0001, odds ratio (OR)=2.43, 95% confidence interval=1.54-3.86) also after correction for DRB1*03-DQA1*0501-DQB1*0201, DRB1*04-DQA1*0301-DQB1*0302, and sex. Meta-analysis of five studies revealed a significant association of CTLA4+49 allele G with AAD (P<0.0001) with an overall OR of 1.48 (1.28-1.71).

CONCLUSIONS

The CTLA4+49 polymorphism is strongly associated with genetic risk for AAD, independently from the well-known association with HLA class II genes.

Persistent increase of osteoprotegerin levels after cortisol normalization in patients with Cushing's syndrome

OBJECTIVE

Osteoprotegerin (OPG) has been identified as a decoy receptor that inhibits osteoclast differentiation and, more recently, as a paracrine regulator of vascular calcification. OPG is suppressed by glucocorticoids (GC); however, results from experimental and clinical studies are not univocal. The aim of this study was to evaluate OPG and bone metabolism in patients with Cushing's syndrome (CS) before and after cure.

DESIGN AND METHODS

Twenty-six patients with CS (all women, mean age: 39.1+/-11.9 years) and 24 age- and gonadal status-matched healthy women were studied for bone mineral density, bone metabolism, OPG, and receptor activator of nuclear factor-kB ligand at baseline. Twelve patients were also studied 6-18 months after surgery, with persistent normalization of cortisol levels.

RESULTS

OPG was significantly higher and osteocalcin (OC) was significantly lower in CS patients than in controls (OPG: 4.17+/-1.23 vs 2.95+/-0.79 pmol/l, P=0.00001; OC: 15.0+/-6.1 vs 18.8+/-6.8 ng/ml, P=0.04 in CS and controls respectively). After cure, we found no difference in OPG levels, despite a significant increase in OC levels (from 16.4+/-11 to 37.2+/-15 ng/ml, P=0.03).

CONCLUSION

Patients with CS showed increased OPG serum levels that remained unchanged after recovery, despite a restoration of bone formation. We speculate that high levels of OPG could reflect the persistent damage of the GCs on cardiovascular system.

Hypertension in Cushing's syndrome: from pathogenesis to treatment

Hypertension is one of the most distinguishing features of endogenous Cushing's syndrome (CS), as it is present in about 80% of adult patients whereas in children its prevalence is about 47%. Hypertension in CS is significantly correlated with the duration of hypercortisolism and results from the interplay between several pathophysiological mechanisms regulating plasma volume, peripheral vascular resistance and cardiac output, all of which are increased in this state. Glucocorticoids cause hypertension through several mechanisms: their intrinsic mineralocorticoid activity; through activation of the renin-angiotensin system; by enhancement of vasoactive substances, and by causing suppression of the vasodilatory systems. In addition, glucocorticoids may exert some hypertensive effects on cardiovascular regulation through the CNS via both glucocorticoid and mineralocorticoid receptors. Hypertension in CS usually resolves with surgical removal of the tumor, but some patients require pharmacological antihypertensive treatment both pre- and postoperatively. Thiazides and furosemide should be avoided, while adrenergic blockade and calcium channel antagonists are usually ineffective. Mineralocorticoid receptor antagonists, Ang II blockers and ACE inhibitors are good anti-hypertensive options; PPAR-γ agonists may help in many aspects of the insulin resistance syndrome. The relatively selective glucocorticoid receptor antagonist Mifepristone (RU 486) could reduce blood pressure in patients with CS. Neuromodulatory agents such as the serotonin inhibitors cyproheptadine and ritanserin, valproid acid, dopamine agonists, somatostatin analogs may occasionally be effective, as well as drugs acting directly at the adrenal levels, such as Ketoconazole and aminoglutetimide or even opDDD. Treating hypertension in CS remains a difficult task and a big challenge, in order to decrease the morbidity and mortality associated with the disease.

Within-patient reproducibility of the aldosterone: renin ratio in primary aldosteronism

The plasma aldosterone concentration:renin ratio (ARR) is widely used for the screening of primary aldosteronism, but its reproducibility is unknown. We, therefore, investigated the within-patient reproducibility of the ARR in a prospective multicenter study of consecutive hypertensive patients referred to specialized centers for hypertension in Italy. After the patients were carefully prepared from the pharmacological standpoint, the ARR was determined at baseline in 1136 patients and repeated after, on average, 4 weeks in the patients who had initially an ARR > or =40 and in 1 of every 4 of those with an ARR <40. The reproducibility of the ARR was assessed with Passing and Bablok and Deming regression, coefficient of reproducibility, and Bland-Altman and Mountain plots. Within-patient ARR comparison was available in 268 patients, of whom 49 had an aldosterone-producing adenoma, on the basis of the "4-corner criteria." The ARR showed a highly significant within-patient correlation (r=0.69; P<0.0001) and reproducibility. Bland-Altman plot showed no proportional, magnitude-related, or absolute systematic error between the ARR; moreover, only 7% of the values, for example, slightly more than what could be expected by chance, fell out of the 95% CI for the between-test difference. The accuracy of each ARR for pinpointing aldosterone-producing adenoma patients was approximately 80%. Thus, although it was performed under different conditions in a multicenter study, the ARR showed a good within-patient reproducibility. Hence, contrary to previously claimed poor reproducibility of the ARR, these data support its use for the screening of primary aldosteronism.

Withdrawn: Case detection, diagnosis, and treatment of patients with primary aldosteronism: an Endocrine Society clinical practice guideline

Ahead of Print article withdrawn by publisher.

Reduced nitric oxide levels in acromegaly: cardiovascular implications

Acromegaly is characterized by major cardiovascular alterations. Although the underlying mechanisms of these vascular modifications have not been elucidated, recent studies have focused on endothelial dysfunction. Nitric oxide (NO) may contribute to increased vascular resistance, reduced platelet aggregation, inhibition of smooth muscle cell proliferation, and reduction of lipoxygenase activity. At present, no data on NO production in acromegalics are available. The aim of this study was to evaluate the effect of high levels of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) present in acromegaly on NO pathway to investigate the role played by this molecule in the cardiovascular changes experienced by these patients. We studied 13 acromegalics and 12 sex- and age-matched normotensive controls. Platelet NO levels were measured in the supernatant of lysed platelets. Endothelial NO synthase (eNOS) was determined by Western blot analysis of platelets. NO concentrations were significantly reduced in patients (p<0.0001). There were no differences between male and female patients, nor were platelet NO levels and the presence/absence of hypertension related in acromegalics; by contrast, NO concentrations inversely correlated with GH (p=0.03) and IGF-1 (p=0.04) levels, and with disease duration (p=0.04). eNOS protein concentrations were significantly reduced in the platelets of patients compared with controls (p<0.0001). This study demonstrates for the first time a strong reduction in platelet NO concentrations in acromegalic patients due to reduced eNOS expression. Moreover the inverse correlation of NO levels with GH, IGF-1 and disease duration suggests that reduced levels of platelet NO linked to GH excess may contribute to the vascular alterations affecting patients with acromegaly.

Genetics of adrenal tumors

The impact of genetics and genomics on clinical medicine is becoming more and more important. Endocrinology pioneered the development of molecular medicine, but also the study of adrenal tumors had a great impact in this field. Particularly important was the detection of genetics of tumors derived from the adrenal medulla, as well as that of those derived from the sympathetic and parasympathetic paraganglia. The identification of mutations in one of the several pheochromocytoma/paraganglioma susceptibility genes may indicate a specific clinical management drive. Less well understood is the genetics of adrenal cortex tumors, in particular adrenocortical carcinoma, a rare and particularly aggressive disease. There are only a few examples of hereditary transmission of adrenocortical carcinoma, but the analysis of low penetrance genes by genome wide association study may enable us to discover new genetic mechanisms responsible for adrenocortical-derived tumors.

Iodine status in pregnancy: role of dietary habits and geographical origin

OBJECTIVES

A study was conducted on iodine status during pregnancy and its dependence on dietary habits, racial and geographical origin, and time since arrival in Italy.

DESIGN AND METHODS

We enrolled 322 consecutive pregnant women: 217 Italians, 62 Eastern Europeans and 43 from Northern and Central Africa. All women completed a food frequency questionnaire on their dietary habits. The urinary iodide concentration (UIC) was determined in spot morning urine samples.

RESULTS

In the group as a whole, the median UIC was 83 microg/l; the UIC was < 50 in 33% and of 150 microg/l or more in 27%; it was significantly lower in Africans and Eastern Europeans than in Italians (medians 45 and 46 vs. 100 microg/l, respectively, P = 0.005). For the foreign women, there was a significant correlation between UIC and time since arrival in Italy (r = 0.22, P = 0.02). A significant link emerged between UIC and cow's milk intake (P = 0.0001). Iodine supplements were used by 40% of the women, and UIC were higher in those who did so than in those who did not (median 103 vs. 75 microg/l, P = 0.03), particularly if the latter did not drink milk (median 98 vs. 42 microg/l, P = 0.01). Multivariate analysis showed that milk was the only variable influencing UIC (OR 1.29, P = 0.0005).

CONCLUSIONS

(i) Iodine levels are too low among pregnant women in our region, and particularly in foreign women. (ii) Cow's milk intake is their main source of iodine. (iii) Iodine supplementation is mandatory during pregnancy, particularly for women do not drink milk.

Adrenocorticotropic Hormone Stimulation During Adrenal Vein Sampling for Identifying Surgically Curable Subtypes of Primary Aldosteronism

Adrenocorticotropic hormone administration was proposed to overcome the biases associated with pulsatile aldosterone secretion during adrenal venous sampling, but the usefulness of different protocols of stimulation was never systematically assessed. We, therefore, compared the effects of a high dose (HD; 250 μg IV as a bolus), a very low dose (VLD; 250 pg IV), and an intermediate dose (ID; 50 μg/h) of adrenocorticotropic hormone on the selectivity index (SI) and the lateralization index in primary aldosteronism patients, using the diagnosis of aldosterone-producing adenoma, based on pathology and follow-up data, as a reference. The HD (n=47) significantly increased plasma cortisol concentration in infrarenal inferior vena cava (+79%) blood and the SI on both sides (SI RIGHT +113% and SI LEFT +131%), as compared with baseline values. The ID (n=14) also markedly increased both plasma cortisol concentration inferior vena cava (+93%) and the SI (SI RIGHT +690% and SI LEFT +410%); the very low dose (n=6) had no effect on either the plasma cortisol concentration or SI. In the patients with unilateral aldosterone-producing adenoma, the increase of selectivity with the HD and ID was counterbalanced by a confounding effect on the correct identification of the aldosterone-producing adenoma side, which was attributed to the wrong side in 3.0% and 12.5% with HD and ID, respectively. In conclusion, the HD and the ID, but not the very low dose, adrenocorticotropic hormone stimulation protocol facilitated the ascertainment of selectivity of adrenal vein catheterization. However, this favorable effect was overridden by a confounding effect on the identification of lateralized aldosterone excess to the aldosterone-producing adenoma side. Hence, we do not recommend adrenocorticotropic hormone stimulation.

Efficacy of the new long-acting formulation of lanreotide (lanreotide Autogel) in somatostatin analogue-naive patients with acromegaly

OBJECTIVE

To evaluate efficacy and safety of lanreotide autogel (ATG) 120 mg injections every 4-8 weeks in somatostatin analogue-naïve patients with acromegaly.

DESIGN

Open, non-comparative, phase III, multicenter clinical study.

METHODS

Fifty-one patients (28 women, aged 19-78 yr): 39 newly diagnosed (de novo) and 12 who had previously undergone unsuccessful surgery (post-op, 11 macro and 1 micro) were studied. ATG 120 mg was initially given every 8 weeks for 24 weeks and subsequently changed according to GH levels: if <or=2.5 microg/l every 8 weeks (group A, 17 patients); if 2.5-5 microg/l every 6 weeks (group B, 15 patients); and if >5 microg/l every 4 weeks (group C, 19 patients). Treatment duration was 48-52 weeks. The primary objective was to control GH and IGF-I levels (GH<or=2.5 microg/l and IGF-I normalized for age/gender). Secondary objectives were to assess GH, IGF-I, and acid-labile subunit (ALS) decrease, improvement of clinical symptoms and quality of life (QoL).

RESULTS

GH levels normalized in 32 patients (63%), similarly in de novo and post-op patients (72% vs 50%, p=0.48); in 100% of group A, in 73% of group B and in 21% of group C (p<0.0001). IGF-I levels normalized in 19 patients (37%), similarly in the de novo and post-op patients (33% vs 50%, p=0.48): in 65% of group A, 33% of group B, and in 16% of group C. Circulating GH levels decreased by 80+/-17%, IGF-I levels by 44+/-27%, and ALS by 30+/-17%. Symptoms (hyperhidrosis (68.6%), swelling (68.6%), asthenia (58.8%), spine arthralgia (54.9%), and paresthesias (52.9%) and QoL (from 9.1+/-7.9 to 6.1+/-6.6) significantly improved (p<0.001). No patient withdrew from the study because of adverse events (AE). The most frequent AE was diarrhea (76.2% of patients): at study end 16 mild and 1 moderate diarrhea were recorded. Gallstones developed in 12% of patients.

CONCLUSION

ATG 120 mg in somatostatin-naïve patients with acromegaly controls GH secretion in 63% and IGF-I secretion in 37% during a 48-52 week period without any difference between de novo and post-op patients. The treatment was associated with improvement in clinical symptoms and QoL and with a good, safe profile.

Adrenocortical cancer treatment

BACKGROUND

With a reported incidence of 1 to 2 cases per million, adrenocortical cancer (ACC) is a rare disease with poor prognosis. Age distribution shows two peaks: early childhood and between age 40 and 50 years, with females more frequently affected. Sequelae can include Cushing syndrome, virilization and hypertension or local symptoms consistent with abdominal obstruction. Although most cases of ACC are of sporadic origin, they may also occur as part of a congenital or familial disease in which the genetic abnormalities are well established. ACC can also be discovered incidentally in asymptomatic individuals. In sporadic ACC, some molecular modifications are commonly observed (i.e., overexpression of insulin-like growth factor II or vascular endothelial growth factor and somatic mutations of tumor protein 53). When surgical resection of the tumor is impossible or ineffective, chemotherapy with etoposide, doxorubicin and cisplatin plus mitotane or with streptozotocin plus mitotane is frequently used; however, the overall survival rates are disappointing.

CONCLUSIONS

Hormonal evaluation is essential to diagnose ACC and the prognosis depends on many factors. New treatments, such as insulin-like growth factor I receptor antibodies, tyrosine kinase inhibitors and other antiangiogenic compounds, are now being intensively investigated to identify better therapies for this extremely severe malignant neoplasia.

Cyclic Cushing's syndrome: an overview

Cyclic Cushing's syndrome (CS) is a disorder in which glucocorticoid levels are alternately normal and high, the latter occurring in episodes that can last from a few days to several months. It is more common in children than in adults. Cyclic CS may be either of the two different forms of CS (ACTH-dependent or -independent CS). Clinically, it may present with one or many symptoms, depending on the duration of disease activity and the timing of the fluctuations. A serotoninergic influence, cyclic changes in central dopaminergic tone, spontaneous episodic hemorrhage in the tumor, and the action of inflammatory cytokines with antitumor properties are some of the mechanisms suggested to explain the physiopathology of this phenomenon but the exact mechanism remains to be clarified. The cyclic pattern of hypercortisolism can delay the final diagnosis of CS and make it difficult to interpret the results of dynamic tests. Patients may have paradoxical responses to dexamethasone that can reflect increasing or decreasing levels of endogenous activity. Hormone assessments have to be repeated periodically when a diagnosis of CS is suspected. The cyclic pattern can also interfere with medical treatment because patients may show unexpected clinical and biochemical signs of hypocortisolism when cortisol secretion cyclically returns to normal, so an accurate follow-up is mandatory in these patients.

Concomitant therapies (glucocorticoids and sex hormones) in adult patients with growth hormone deficiency

Adult-onset GH deficiency (GHD), mostly due to organic lesions of the pituitary-hypothalamic region, is frequently associated with multiple anterior pituitary deficiencies that need long-term substitutive treatment. The GH-IGF-I axis may play an important role in modulating peripheral metabolism of hormones (adrenal, thyroid, and sex hormones) and these interactions may have clinically significant implications on the phenotypes of adult GHD patients and on the effects of the combined replacement hormonal treatment of this condition. By accelerating the peripheral metabolism of cortisol, GH therapy may precipitate adrenal insufficiency in susceptible hypopituitary patients; estrogen replacement blunts the response to GH in women whereas in men with androgen substitution the responsivity increases over time. Endocrinologists should be mindful of these phenomena when starting patients with hypopituitarism on GH replacement therapy.

Case detection, diagnosis, and treatment of patients with primary aldosteronism: an endocrine society clinical practice guideline

OBJECTIVE

Our objective was to develop clinical practice guidelines for the diagnosis and treatment of patients with primary aldosteronism.

PARTICIPANTS

The Task Force comprised a chair, selected by the Clinical Guidelines Subcommittee (CGS) of The Endocrine Society, six additional experts, one methodologist, and a medical writer. The Task Force received no corporate funding or remuneration.

EVIDENCE

Systematic reviews of available evidence were used to formulate the key treatment and prevention recommendations. We used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) group criteria to describe both the quality of evidence and the strength of recommendations. We used "recommend" for strong recommendations and "suggest" for weak recommendations.

CONSENSUS PROCESS

Consensus was guided by systematic reviews of evidence and discussions during one group meeting, several conference calls, and multiple e-mail communications. The drafts prepared by the task force with the help of a medical writer were reviewed successively by The Endocrine Society's CGS, Clinical Affairs Core Committee (CACC), and Council. The version approved by the CGS and CACC was placed on The Endocrine Society's Web site for comments by members. At each stage of review, the Task Force received written comments and incorporated needed changes.

CONCLUSIONS

We recommend case detection of primary aldosteronism be sought in higher risk groups of hypertensive patients and those with hypokalemia by determining the aldosterone-renin ratio under standard conditions and that the condition be confirmed/excluded by one of four commonly used confirmatory tests. We recommend that all patients with primary aldosteronism undergo adrenal computed tomography as the initial study in subtype testing and to exclude adrenocortical carcinoma. We recommend the presence of a unilateral form of primary aldosteronism should be established/excluded by bilateral adrenal venous sampling by an experienced radiologist and, where present, optimally treated by laparoscopic adrenalectomy. We recommend that patients with bilateral adrenal hyperplasia, or those unsuitable for surgery, optimally be treated medically by mineralocorticoid receptor antagonists.

Urine cortisol and cortisone and water intake in athletes

AIM

The aim of this study was to investigate the urine cortisol (F) and cortisone (E) relation, having a well-defined water intake.

METHODS

Urine specimens were collected from 10 male trained cyclists (19+/-1 year, 70+/-4 kg, 179+/-4 cm), at rest just before the test (pre-exe) and until 45 min after the cycle ergometer exercise test (45 min at 50-60% VO2max) (post-exe) in the morning. This investigation measured the diuresis in the pre-exe and post-exe after each athlete had drunk 1 L of water from waking-up, after bladder emptying, to the start of the test (pre-exe) and 1 L during the 45 min after the exercise (post-exe).

RESULTS

Urinary F and E concentrations demonstrated a significant decrease comparing pre-exe with post-exe (177+/-134 vs 64+/-21 and 706+/-475 vs 372+/-178 nmol.L(-1) respectively, p < 0.05). This significant decrease was verified when diuresis and urinary creatinine were taken into account and the ratio measured.

CONCLUSION

One litre of water intake after exercise seemed to have no effect on urine F and E excretion. Moreover the urine F/E ratio was not statistically different comparing pre-exe with post-exe.

Factors influencing the rising rates of adrenal surgery: analysis of a 25-year experience

BACKGROUND

Adrenal surgery has been radically changed by laparoscopy and it is reasonable to wonder whether the increase in the number of adrenalectomies is entirely justified. There is still debate on the transperitoneal versus the retroperitoneal approach, the advantages and drawbacks of which are discussed here.

METHODS

Between 1983 and 2007, we performed 279 adrenalectomies in 264 consecutive patients, divided into two groups: before and after the advent of laparoscopic adrenalectomy (LA). We analyzed the factors that increased the number of adrenalectomies in recent years. The LAs were further divided into three consecutive periods and the morbidity and conversion rates, and mean operating times were compared.

RESULTS

More procedures were performed after the advent of LA, i.e., 55 (19.7%) beforehand versus 224 (80.3%) afterwards, irrespective of the type of disease, for instance: incidentaloma, 17.6% versus 82.4% (p \ 0.0001); pheochromocytoma, 20.7% versus 79.3% (p\0.0001); Conn's disease, 19.8% versus 80.2% (p \ 0.0001); Cushing's disease, 17.2% versus 82.8% (p\0.0001); cortical carcinoma, 30% versus 70% (p\0.001). Analyzing the three LA periods, operating times were the only statistically significant variable (p\0.0001).

CONCLUSIONS

The progressive increase in the number of adrenalectomies performed is due more to a better understanding of adrenal disease than to the availability of minimally invasive techniques. The choice of a laparoscopic approach (trans- or retroperitoneal) should depend on the surgeon's experience.

Adrenal morpho-functional alterations in patients with acromegaly

Acromegaly is associated with a greater morbidity and higher incidence of tumors, possibly due to the permissive role of elevated GH and IGF-I levels. In the general population, adrenal masses are frequently discovered (prevalence 1-5%) at computed tomography (CT). We evaluated the prevalence of adrenal lesions in patients with acromegaly. We studied 94 acromegalic patients, 54 females (mean age 55.0+/-16.0 yr) and 40 males (mean age 50+/-14 yr) referred to 5 Endocrinology Units between 2001-2003; 49 had active disease and 45 had been treated with surgery and/or were controlled with medical therapy. Abdominal CT showed adrenal lesions in 27 patients; 9 of them had unilateral masses (10%) with benign features (diameter 0.5-3 cm) and 18 had hyperplasia (14 monolateral and 4 bilateral), with no significant differences between patients with active vs controlled disease, and with no correlation between prevalence of masses and duration of disease, GH and IGF-I levels. Hormone study (urinary free cortisol, catecholamines/metanephrines, upright plasma renin activity and aldosterone, morning plasma ACTH and low-dose dexamethasone suppression test) disclosed no major endocrine alterations. During a 1-yr follow-up, the adrenal masses increased in size in 3 cases and 1 patient also developed subclinical Cushing's syndrome. Adrenal lesions seem more frequent in acromegaly than in the general population, but no single factor (GH/IGF-I levels or disease duration) predicts them. The masses appear to be benign and nonhypersecreting, but a longer follow-up is recommended to disclose any changes in their morphofunctional state.

Body mass index predicts plasma aldosterone concentrations in overweight-obese primary hypertensive patients

CONTEXT

Body mass index (BMI) shows a direct correlation with plasma aldosterone concentration (PAC) and urinary aldosterone excretion in normotensive individuals; whether the same applies to hypertensive patients is unknown.

OBJECTIVE

Our objective was to determine if BMI predicts PAC and the PAC/plasma renin activity ratio [aldosterone renin ratio (ARR)] in hypertensive patients, and if this affects the identification of primary aldosteronism (PA).

DESIGN

This was a prospective evaluation of consecutive hypertensive patients referred nationwide to specialized hypertension centers.

MAIN OUTCOME MEASURES

Sitting PAC, plasma renin activity, and the ARR, baseline and after 50 mg captopril orally with concomitant assessment of parameters, including BMI and daily sodium intake, were calculated.

RESULTS

Complete biochemical data and a definite diagnosis were obtained in 1125 consecutive patients. Of them 999 had primary (essential) hypertension (PH) and 126 (11.2%) PA caused by an aldosterone-producing adenoma in 54 (4.8%). BMI independently predicted PAC (beta = 0.153; P < 0.0001) in PH, particularly in the overweight-obese, but not in the PA group. Covariance analysis and formal comparison of the raw, and the BMI-, sex-, and sodium intake-adjusted ARR with receiver operator characteristic curves, showed no significant improvement for the discrimination of aldosterone-producing adenoma from PH patients with covariate-adjusted ARR.

CONCLUSIONS

BMI correlated with PAC independent of age, sex, and sodium intake in PH, but not in PA patients. This association of BMI is particularly evident in overweight-obese PH patients, and suggests a pathophysiological link between visceral adiposity and aldosterone secretion. However, it does not impact on the diagnostic accuracy of the ARR for discriminating PA from PH patients.