[Swedish guidelines for the management of adrenal incidentalomas]. / Nationellt vårdprogram för adrenala incidentalom - Programmet har harmoniserats med europeiska riktlinjer ­ ger förenklad handläggning av patienter.

Swedish guidelines for the management of adrenal incidentalomas  Adrenal incidentalomas are seen in about five percent of abdominal CT examinations, and in most cases represent non-hormone-producing adrenocortical adenomas, but hormone-producing or malignant lesions occur. Revised Swedish guidelines for the evaluation and management of adrenal incidentalomas based on recently published European guidelines are presented. The importance of a thorough radiological, clinical and biochemical initial evaluation is emphasized. Long-term biochemical follow-up is not recommended and use of CT contrast medium ¼washout« calculation is omitted. No radiological evaluation or follow-up indicated for adrenal incidentalomas <1 cm size. For patients with diagnosed lipid rich adenomas (≤ 10 HU) 1-4 cm in size no radiological follow-up is suggested after initial evaluation.

Increased mortality in patients with adrenal incidentalomas and autonomous cortisol secretion: a 13-year retrospective study from one center.

PURPOSE: To compare long-term outcomes in patients with adrenal incidentalomas (AIs) with the response to a 1 mg overnight dexamethasone suppression test (DST). METHODS: Consecutive patients with "non-functional" AIs (n = 365) were examined. Patients with overt hormone excess, adrenocortical cancer and known malignancy had been excluded. Patients were classified to normal cortisol secretion group (n = 204, DST ≤ 50 nmol/l), possible autonomous cortisol secretion group (n = 128, DST 51-138 nmol/l) and autonomous cortisol secretion group (n = 33, DST ≥ 138 nmol/l). RESULTS: Thirty-seven patients (10.1%) deceased during the follow-up period (5.2 ± 2.3 years): 16(7.8%) in the non-secreting group (time from diagnosis to death: 3.9 ± 2.9 years), 15 in the possible autonomous cortisol secretion group (11.7%, 3.2 ± 1.8 years) and 6 in the autonomous cortisol secretion group (18.2%, 2.3 ± 1.5 years), respectively (P = 0.019). Multivariate analysis only found significant association with age and the tumour size but if cortisol levels post-DST were analysed as a continuous variable it was significant as well. All deaths in autonomous cortisol secretion group were due to cancer not related to adrenal glands. Hypertension, cardiovascular disease and medications were more common in the possible and autonomous cortisol secretion group, especially in the former. More bilateral AIs and larger AI size were found in the two latter groups. CONCLUSIONS: Patients with autonomous cortisol secretion had higher mortality than those with non-functioning AIs though cortisol levels post-DST as a continuous variable, age and tumour size were better predictor of mortality. Cardiovascular disease and osteoporosis medication seemed more prevalent in the possible and autonomous cortisol secretion groups, especially in the former.

CLINICAL OUTCOMES IN ADRENAL INCIDENTALOMA: EXPERIENCE FROM ONE CENTER.

OBJECTIVE: To investigate the outcome in patients with adrenal incidentaloma (AI). METHODS: A retrospective evaluation of 637 patients with AI referred to a tertiary center over 8 years. Radiologic and hormonal evaluations were performed at baseline. Follow-up imaging was carried out if necessary, and hormonal evaluation was performed at 24 months according to national guidelines. RESULTS: The mean age was 62.7 ± 11.6 years, and the mean AI size was 25.3 ± 17.0 mm at presentation. Hormonal evaluation revealed that 85.4% of all tumors were nonfunctioning adenomas, 4.1% subclinical Cushing syndrome (SCS), 1.4% pheochromocytoma, 1.4% primary hyperaldosteronism, 0.8% Cushing syndrome, 0.6% adrenocortical carcinoma, 0.3% congenital adrenal hyperplasia, 2.2% metastasis to adrenals, and 3.8% other lesions of benign origin. Bilateral tumors were found in 11%, and compared to unilateral tumors, SCS was more prevalent. Only 2 cases were reclassified during follow-up, both as SCS, but neither had had a dexamethasone suppression test performed at initial work-up. In patients diagnosed with an adrenal metastasis, 92.9% were deceased within 2 years. Excluding those with malignant tumors, 12.9% of patients died during the study period of up to 11 years due to other causes than adrenal. CONCLUSION: Most AIs were benign, but a small fraction of tumors were functional and malignant. The prognosis of patients with adrenal metastasis was extremely poor, but otherwise, the mortality rate was similar to that for the general population. Follow-up of AIs <4 cm with an initial nonfunctional profile and benign radiologic appearance appears unwarranted, but screening for congenital adrenal hyperplasia should be considered.

Primary aldosteronism: functional histopathology and long-term follow-up after unilateral adrenalectomy.

OBJECTIVES: To investigate the long-term outcome after unilateral adrenalectomy in patients with primary aldosteronism (PA) and to establish the role of functional pathology for the final diagnosis of aldosterone-producing adenoma (APA) or hyperplasia. DESIGN: A single-centre, retrospective cohort study in a hospital setting. PATIENTS: Consecutive patients with PA, n = 120, who underwent unilateral adrenalectomy between 1985 and 2010. Preoperative and postoperative data were analysed. To indicate the site of aldosterone secretion in the resected adrenal, we added functional methods to routine histopathology, using in situ hybridization and immunohistochemistry to detect the presence of enzymes needed for aldosterone (CYP11B2) and cortisol (CYP11B1, CYP17A1) synthesis. RESULTS: The median follow-up was 5 years and the cure rate of PA 91%. Hypertension was improved in 97% and normalized in 38%. Functional histopathology changed the final diagnosis from APA to hyperplasia in 6 cases (7%). Five of these had no expression of or staining for aldosterone synthase in the adenoma, but only in nodules in the adjacent cortex. All except one APA patient were cured of PA. They had lower preoperative serum potassium and higher 24-h urinary aldosterone than patients with hyperplasia. Among patients with hyperplasia 16 of 26 were cured. CONCLUSIONS: Most patients were cured of PA by unilateral adrenalectomy. Almost all noncured benefitted from the operation as the blood pressure improved. Functional histopathology proved helpful in the distinction between APA and hyperplasia, and we recommend that functional histopathology should be added to routine histopathology to improve the diagnostic evaluation and aid in tailoring the follow-up.

Further characterization of human glucocorticoid receptor mutants, R477H and G679S, associated with primary generalized glucocorticoid resistance.

OBJECTIVE: Primary generalized glucocorticoid resistance is a rare condition characterized by a generalized insensitivity to glucocorticoids, to some extent due to an impaired function of the glucocorticoid receptor. Our earlier genetic analysis of the human glucocorticoid receptor (hGR) in 12 unrelated patients with primary generalized glucocorticoid resistance revealed two new mutations, R477H in exon 4 and G679S in exon 8 in two patients. In order to further study the molecular mechanisms underlying the phenotype of these mutations we have investigated their effect on glucocorticoid signal transduction. METHODS: We have studied the DNA-binding ability of the R477H mutant with an electrophoretic mobility shift assay (EMSA). The ability of the R477H and the G679S mutants to affect TNFα induced NF-κB activity and wild-type GR signalling was studied in transient transfection assays. RESULTS: In EMSA the R477H mutation showed a reduced ability to bind to a glucocorticoid-response element compared to the wild-type GR. In transient transfection assays both the R477H mutant and the G679S mutant showed a dominant negative effect on co-transfected wild-type GR in Cos 7 cells. However, both mutants showed full capacity to repress TNFα-induced NF-κB activity. CONCLUSION: The impaired DNA-binding of the hGR, R477H mutant may explain the severe phenotype of cortisol resistance seen with this mutation. The dominant negative effects of both mutants on wild-type GR signalling probably contribute to the patients' cortisol resistance.

Screening for primary aldosteronism in a primary care unit.

OBJECTIVE: Primary aldosteronism (PA) is a common cause of secondary hypertension but the reported prevalence varies. Few studies have been carried out in primary care. We investigated the prevalence of PA by screening with the aldosterone to renin ratio (ARR). DESIGN AND METHODS: Patients with hypertension were recruited from a primary care unit and investigated in a university hospital setting. Of 235 patients asked to participate 77% accepted. Antihypertensive medication apart from amiloride and spironolactone was maintained. The cut-off level for a positive ARR was lower than in clinical practice (> 50 pmol/ng with aldosterone > 350 pmol/l) to adjust for any suppressive effects of medication. A positive ARR was followed by a confirmatory evaluation. RESULTS: The frequency of confirmed PA was 1.6% and including cases with a positive ARR who refused further investigation it would be 3.3% at most. In primary hypertension angiotensin receptor blockers, angiotensin-converting enzyme inhibitors and thiazide diuretics markedly suppressed the ARR by increasing renin levels. CONCLUSION: The detection rate of PA in our study is in the lower part of the wide range shown in previous studies. Larger population studies are needed to establish the true prevalence in primary care. Future studies may clarify if the present cut-off levels allow detection of very mild PA.

Novel mutations in the SLC12A3 gene causing Gitelman's syndrome in Swedes.

PURPOSE: Gitelman's syndrome (GS) is an inherited autosomal recessive disorder due to loss of function mutations in the SLC12A3 gene encoding the Na-Cl co-transporter (NCCT), the target of thiazide diuretics. The defective function of the NCCT, which normally is expressed in the apical membrane of the distal convolute tubule in the kidney, leads to mild hypotension, hypokalemia, hyperreninemic hyperaldosteronism, mild metabolic alkalosis, hypomagnesemia and hypocalciuria. Up to now, more than 100 mutations of the SLC12A3 gene have been described in GS patients. METHODS: We have collected 30 patients from Sweden with a clinical diagnosis of GS and undertaken a mutation screening by SSCP and successive sequencing of the 26 exons and intronic boundaries. Both mutations were identified in most (n = 28, 93%) and at least one mutation was identified in all patients. RESULTS: We found 22 different mutations evenly distributed throughout the gene, 11 of which have not been described previously. The new variants include 8 missense mutations (Glu68Lys, His69Asn, Argl45His, Vall53Met, Gly230Asp, Gly342Ala, Val677Leu and Gly867Ser), 1 insertion (c.834_835insG on exon 6) and 2 splice-site mutations (c.2667 + lT>G substitution in splicing donor site after exon 22, c.1569-1G>A substitution in the splicing acceptor site before exon 13). CONCLUSION: In Swedish patients with the clinical features of GS, disease-causing mutations in the SLC12A3 gene were identified in most patients. The spectrum of GS mutations is wide making full mutation screening of the SLC12A3 gene necessary to confirm the diagnosis.

Adrenal incidentaloma - follow-up results from a Swedish prospective study.

OBJECTIVES: To examine the risk of developing adrenal carcinomas and clinically overt hypersecreting tumours during short-term follow-up in patients with adrenal incidentalomas. DESIGN: 229 (98 males and 131 females) patients with adrenal incidentalomas were investigated in a prospective follow-up study (median time 25 months; range 3-108 months). The patients were registered between January 1996 and July 2001 and followed until December 2004. Twenty-seven Swedish hospitals contributed with follow-up results. METHODS: Diagnostic procedures were undertaken according to a protocol including reinvestigation with computed tomography scans after 3-6 months, 15-18 months and 27-30 months, as well as hormonal evaluation at baseline and after 27-30 months of follow-up. Operation was recommended when the incidentaloma size increased or if there was a suspicion of a hypersecreting tumour. RESULTS: The median age at diagnosis of the 229 patients included in the follow-up study was 64 years (range 28-84 years) and the median size of the adrenal incidentalomas when discovered was 2.5 cm (range 1-8 cm). During the follow-up period, an increase in incidentaloma size of > or =0.5 cm was reported in 17 (7.4%) and of > or =1.0 cm was reported in 12 (5.2%) of the 229 patients. A decrease in size was seen in 12 patients (5.2%). A hypersecreting tumour was found in 2% of the hormonally investigated patients: Cushing's syndrome (n = 2) and phaeochromocytoma (n = 1). Eleven patients underwent adrenalectomy, but no cases of primary adrenal malignancy were observed. CONCLUSIONS: Patients with adrenal incidentaloma had a low risk of developing malignancy or hormonal hypersecretion during a short-term follow-up period.

Upstream transcription factor-1 gene polymorphism is associated with increased adipocyte lipolysis.

OBJECTIVE: Variations in lipid metabolism between individuals could be due to genetic factors. A transmission of a haplotype of the upstream transcription factor-1 (USF-1) gene containing the minor alleles at the usf1s1 and usfs2 loci is described. We investigated whether these polymorphisms are associated with adipocyte lipolysis. METHODS AND RESULTS: A total of 196 healthy obese women were investigated for in vitro lipolysis regulation in sc fat cells, which was set in relation to the usf1s1 C-->T and usf1s2 G-->A polymorphisms in the usf1 gene. The two polymorphisms were in complete linkage disequilibrium. The usf1s1/2 T/A allele was associated with increases in the maximum lipolytic action of noradrenaline (P = 0.005), dobutamine (P = 0.008), terbutaline (P = 0.008), CGP12177 (P = 0.015), and forskolin (P = 0.006). In contrast, no significant genotype effect on lipolytic sensitivity (i.e. half-maximum effective concentration) for any of the drugs was demonstrated. Analysis of adipose tissue mRNA expression in 78 women from genes regulating lipolysis at the postadrenoceptor level showed an increased level of protein kinase A subunit R1alpha in the T/A genotype (P = 0.02). CONCLUSIONS: Polymorphism in the usf1 gene is associated with increased lipolytic effect of catecholamines in fat cells, which is localized at the postadrenoceptor level, possibly, at least, involving protein kinase A.

Mechanisms behind lipolytic catecholamine resistance of subcutaneous fat cells in the polycystic ovarian syndrome.

Lipolytic catecholamine resistance in sc fat cells is observed in polycystic ovarian syndrome (PCOS). The mechanisms behind this lipolysis defect were explored in vitro; sc fat cells were obtained from 10 young, nonobese PCOS women and from 14 matched, healthy control women. Fasting plasma glycerol levels were reduced by one third in PCOS (P < 0.05). Adipocytes of PCOS women were about 25% larger than in the controls (P < 0.05) and had 40% reduced noradrenaline-induced lipolysis (P < 0.05), which could be attributed to a 10-fold decreased beta(2)-adrenoceptor sensitivity (P < 0.05) and low ability of cAMP to activate the protein kinase A (PKA)/hormone-sensitive lipase (HSL) complex (P < 0.05). In PCOS, the adipocyte protein content of beta(2)-adrenoceptors, HSL, and the regulatory II beta-component of PKA were 70%, 55%, and 25% decreased, respectively (P < 0.001); but there was no change in the amount of the catalytic subunit of PKA or of beta(1)-adrenoceptors. Thus, lipolytic catecholamine resistance of sc adipocytes in PCOS is probably attributable to a combination of decreased amounts of beta(2)-adrenergic receptors, the regulatory II beta-component of PKA, and HSL. This may cause low in vivo lipolytic activity and enlarged sc fat cell size and promote later development of obesity in PCOS.

Increased adipose tissue secretion of interleukin-6, but not of leptin, plasminogen activator inhibitor-1 or tumour necrosis factor alpha, in Graves' hyperthyroidism.

OBJECTIVE: This study was designed to investigate adipose tissue secretion of interleukin-6 (IL-6), leptin, tumour necrosis factor alpha (TNF-alpha) and plasminogen activator inhibitor-1 (PAI-1) in Graves' hyperthyroidism. DESIGN: We studied 10 patients before and during (after 8 weeks) anti-thyroid treatment for Graves' hyperthyroidism and 16 healthy, euthyroid control subjects. METHODS: Plasma levels of thyroid hormones and serum/plasma levels of IL-6, leptin, TNF-alpha and PAI-1 were analysed. Subcutaneous fat biopsies were taken for subsequent measurement of IL-6, leptin, TNF-alpha and PAI-1 protein secretion. RESULTS: In patients with Graves' disease, the anti-thyroid treatment resulted in significant reductions of plasma thyroxine and triiodothyronine levels. No differences in serum concentration or adipose tissue secretion of leptin or TNF-alpha were observed either before, as compared with during, anti-thyroid treatment, or in comparison with euthyroid controls. In contrast, plasma PAI-1 activity, but not adipose tissue secretion of PAI-1, was increased both in Graves' disease before as compared with during anti-thyroid treatment (P=0.01) and in thyrotoxic patients compared with euthyroid controls (P=0.0001). Finally, adipose secretion of IL-6 was increased both before (8-fold, P=0.001) and during (6-fold, P<0.0001) treatment as compared with control subjects. Accordingly, serum concentration of IL-6 was also increased by about 50% in thyrotoxic patients as compared with healthy controls (P=0.03). CONCLUSIONS: In Graves' hyperthyroidism regardless of thyroid status, adipose tissue secretion of IL-6, but not of leptin, TNF-alpha or PAI-1, is markedly increased in comparison with euthyroid controls. This suggests that autoimmune thyroidal disorder may regulate adipose tissue release of IL-6.

[Pheochromocytoma--rare and often undiagnosed condition]. / Feokromocytom--ovanligt och ofta odiagnostiserat tillstånd.

Phaeochromocytoma is a rare but important cause of secondary hypertension that can prove fatal when undiagnosed. Several autopsy studies have reported that a large number of undiagnosed tumours occur during life. This review discusses the diagnostic guidelines for phaeochromocytoma. Factors such as hypertension, sustained or paroxysmal, in association with the most common symptoms of headache, sweating and palpitations, can be used to provide a suspicion of phaeochromocytoma. Although measures of plasma methoxylated catecholamines may provide a promising diagnostic method, the cornerstone for diagnosing phaeochromocytoma remains 24 h or overnight sampling of urinary free catecholamines and methoxylated catecholamines.

Major gender differences in the lipolytic capacity of abdominal subcutaneous fat cells in obesity observed before and after long-term weight reduction.

The influence of obesity on the lipolytic capacity of isolated sc fat cells was studied prospectively in 13 women and 10 men, all obese, but otherwise healthy, before and 2 and 3 yr after weight reduction by bariatric surgery. Nonobese subjects (25 women and 17 men) without a family history of obesity served as the control group. Lipolytic capacity was determined after stimulation at different steps of the lipolytic cascade with noradrenaline, isoprenaline, forskolin, and (Bu)(2)AMP. Bariatric surgery was followed by a marked and similar reduction of body mass index and fat cell volume (approximately 40%) in both genders. Before weight loss, lipolytic capacity per cell was elevated in obese women and decreased to normal levels after weight reduction at 2 and 3 yr. However, lipolytic capacity per fat cell surface area was not changed in obese women. In obese men, lipolytic capacity per cell was almost the same as in lean men and was not influenced by weight reduction. Lipolytic capacity was related to fat cell size in women (P = 0.0008; r = 0.58), but not in men (P = 0.67; r = 0.086). The protein content of hormone-sensitive lipase, which determines lipolytic capacity, was significantly lower in obese men and women and increased slightly after weight reduction in men only. Thus, in women, but not in men, the adipocyte lipolytic capacity is influenced by obesity and weight reduction, probably due to changes in fat cell size. These gender differences are not related to the amount of hormone-sensitive lipase protein in adipocytes.

A unique defect in the regulation of visceral fat cell lipolysis in the polycystic ovary syndrome as an early link to insulin resistance.

The etiology of polycystic ovary syndrome (PCOS) is unknown. However, PCOS has a strong resemblance to the insulin resistance (metabolic) syndrome, where an increased rate of visceral fat cell lipolysis is believed to play a pathophysiological role. We hypothesized that primary defects in visceral lipolysis might also exist in PCOS. Ten young, nonobese, and otherwise healthy PCOS women were compared with 13 matched control women. In vitro lipolysis regulation and stoichiometric properties of the final step in lipolysis activation, namely the protein kinase A (PKA)-hormone sensitive lipase (HSL) complex, were investigated in isolated visceral (i.e., omental) fat cells. Body fat distribution and circulating levels of insulin, glucose, and lipids were normal in PCOS women. However, in vivo insulin sensitivity was slightly decreased (P = 0.03). Catecholamine-induced adipocyte lipolysis was markedly (i.e., about twofold) increased in PCOS women due to changes at the postreceptor level, although there was no change in the antilipolytic properties of visceral fat cells. Western blot analyses of visceral adipose tissue showed twofold increased levels of the catalytic and the regulatory Ialpha components of PKA. In contrast, the regulatory RIIbeta component of PKA was almost 50% decreased in visceral adipose tissue in PCOS women. Recent studies on genetically modified mice have shown that a similar transition in the regulatory PKA units induces an increased lipolytic response to catecholamines. Further analysis showed that the level of HSL-short, an enzymatically inactive splice form of HSL, was decreased in PCOS (P < 0.01). The altered lipolysis in PCOS is different from that observed in visceral fat cells in the insulin resistance syndrome that occurs at the level of adrenergic receptors. We concluded that increased catecholamine-induced lipolysis in visceral fat cells may be due to unique alterations in the stoichiometric properties of the adipose PKA-HSL holoenzymes. This could be an early and possibly primary lipolysis defect in PCOS.