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Purpose: Arthropathy is a common and disabling complication of acromegaly. Since in this condition radiological findings rarely correspond to functional impairment, we elected to quantify in a large cohort of acromegalic patients: the degree of motor disability compared with data from general population, the impact of joint involvement on quality of life and work productivity, and to look for associated factors., Methods: In 211 acromegalic patients, 131 with controlled disease and 80 with active disease, eight validated scales were used to evaluate the (i) prevalence and distribution of arthropathy, (ii) degree of motor disability and joint symptoms (VAS, AIMS symptoms and WOMAC), (iii) quality of life (AcroQoL and PASQ) and work capability (WPAI:GH) as consequences of joint complications., Results: Using the WOMAC questionnaire, for which population based normative values are available, a significantly higher prevalence and severity of motor disability was detected in acromegalics compared to the general population from literature. The results provided by the different questionnaires turned out to be highly concordant. All measures of motor disability correlated both with impaired quality of life and motor disability and were worse in females and in patients with higher BMI., Conclusions: The questionnaires VAS, AIMS symptoms, and WOMAC (this latter both as a whole and with its functionality subscale), with their scores, proved to be the most adequate tools to evaluate motor disability and its consequences on both quality of life and work productivity in acromegaly. Female gender and higher BMI are associated with worse articular symptoms.

Purpose: It is well known that methylation plays an important role in regulating tissue expression of proopiomelanocortin (POMC) and recent studies have shown that demethylation can occur also in vitro in neuroendocrine tumors. Aim of the present study was to evaluate whether inhibition of methylation modulates POMC expression and ACTH secretion by human corticotrope tumors., Methods: Twenty two ACTH-secreting pituitary tumors were incubated with 5-AZA-2'-deoxycytidine (AZA), an inhibitor of DNA-methyltransferases, with or without 10 nM corticotropin-releasing hormone (CRH). Both dose response (100 nM-10 μM AZA) and time course (4-96 h) experiments were carried out for measurement of ACTH secretion and POMC gene expression., Results: Incubation with AZA increased constitutive POMC expression and ACTH secretion by human corticotrope adenomas. The effect appeared most notable at 24 and 48 h with 1 μM AZA. Incubation with AZA did not exert an additional stimulatory effect on CRH-stimulated POMC and ACTH., Conclusions: The present study shows that AZA increases POMC gene expression and ACTH secretion in human pituitary ACTH-secreting tumors. This can be taken to indicate that mechanisms set into motion by AZA play a role in the regulation of ACTH secretion/POMC expression in tumoral corticotropes and paves the way to further studies in Cushing's disease.

Differential diagnosis of ACTH-dependent Cushing's syndrome often presents major difficulties. Diagnostic troubles are increased by suboptimal specificity of endocrine tests, the rarity of ectopic ACTH secretion and the frequent incidental discovery of pituitary adenomas. A 43-year-old female reported with mild signs and symptoms of hypercortisolism, and initial hormonal tests and results of pituitary imaging (7-mm adenoma) were suggestive for Cushing's disease. However, inadequate response to corticotrophin-releasing hormone and failure to suppress after 8 mg dexamethasone pointed towards an ectopic source. Total body CT scan visualized only a small, non-specific nodule in the right posterior costophrenic excavation. Inferior petrosal sinus sampling revealed an absent center:periphery ACTH gradient but octreoscan and (18)F-FDG-PET-CT failed to detect abnormal tracer accumulation. We weighed results of the laboratory with those of imaging and decided to remove the lung nodule. Pathology identified a typical, ACTH-staining carcinoid and the diagnosis was confirmed by postsurgical hypoadrenalism. In conclusion, imaging may prove unsatisfactory or even misleading for the etiologial diagnosis of ACTH-dependent Cushing's syndrome and should therefore be interpreted only in context with results of hormonal dynamic testing.

This paper outlines the interferences of the most widely used drugs with hypothalamo-pituitary-adrenal function and the related laboratory parameters, with the purpose of providing practical help to clinicians during testing for hypo- or hypercortisolemic states.

Isolated ACTH deficiency (IAD) is a rare disorder, characterized by secondary adrenal insufficiency (AI) with low or absent cortisol production, normal secretion of pituitary hormones other than ACTH and the absence of structural pituitary defects. In adults, IAD may appear after a traumatic injury or a lymphocytic hypophysitis, the latter possibly due to autoimmune etiology. Conversely, a genetic origin may come into play in neonatal or childhood IAD. Patients with IAD usually fare relatively well during unstressed periods until intervening events spark off an acute adrenal crisis presenting with non specific symptoms, such as asthenia, anorexia, unintentional weight loss and tendency towards hypoglycemia. Blood chemistry may reveal mild hypoglycemia, hyponatremia and normal-high potassium levels, mild anemia, lymphocytosis and eosinophilia. Morning serum cortisol below 3 microg/dl are virtually diagnostic for adrenal insufficiency. whereas cortisol values comprised between 5-18 microg/dl require additional investigations: insulin tolerance test (ITT) is considered the gold standard but-when contraindicated-high or low dose-ACTH stimulation test with serum cortisol determination provides a viable alternative. Plasma ACTH concentration and prolonged ACTH infusion test are useful in differential diagnosis between primary and secondary adrenal insufficiency. For some patients with mild, near-to-asymptomatic disease, glucocorticoid replacement therapy may not be required except during stressful events; for symptomatic patients, replacement doses i.e., mean daily dose 20 mg (0.30 mg/kg) hydrocortisone or 25 mg (0.35 mg/kg) cortisone acetate, are usually sufficient. Administration of mineralocorticoids is generally not necessary as their production is maintained.

Hypopituitarism is the partial or complete insufficiency of anterior pituitary hormone secretion and may result from pituitary or hypothalamic disease. The reported incidence (12-42 new cases per million per year) and prevalence (300-455 per million) is probably underestimated if its occurrence after brain injuries (30-70% of cases) is considered. Clinical manifestations depend on the extent of hormone deficiency and may be non specific, such as fatigue, hypotension, cold intolerance, or more indicative such as growth retardation or impotence and infertility in GH and gonadotropin deficiency, respectively.A number of inflammatory, granulomatous or neoplastic diseases as well as traumatic or radiation injuries involving the hypothalamic-pituitary region can lead to hypopituitarism. Several genetic defects are possible causes of syndromic and non syndromic isolated/multiple pituitary hormone deficiencies. Unexplained gonadal dysfunctions, developmental craniofacial abnormalities, newly discovered empty sella and previous pregnancy-associated hemorrhage or blood pressure changes may be associated with defective anterior pituitary function.The diagnosis of hypopituitarism relies on the measurement of basal and stimulated secretion of anterior pituitary hormones and of the hormones secreted by pituitary target glands. MR imaging of the hypothalamo-pituitary region may provide essential information. Genetic testing, when indicated, may be diagnostic.Secondary hypothyroidism is a rare disease. The biochemical diagnosis is suggested by low serum FT4 levels and inappropriately normal or low basal TSH levels that do not rise normally after TRH. L-thyroxine is the treatment of choice. Before starting replacement therapy, concomitant corticotropin deficiency should be excluded in order to avoid acute adrenal insufficiency. Prolactin deficiency is also very rare and generally occurs after global failure of pituitary function. Prolactin deficiency prevents lactation. Hypogonadotropic hypogonadism in males is characterized by low testosterone with low or normal LH and FSH serum concentrations and impaired spermatogenesis. Hyperprolactinemia as well as low sex hormone binding globulin concentrations enter the differential diagnosis. Irregular menses and amenorrhea with low serum estradiol concentration (<100 pmol/l) and normal or low gonadotropin concentrations are the typical features of hypogonadotropic hypogonadism in females. In post menopausal women, failure to detect high serum gonadotropin values is highly suggestive of the diagnosis. In males, replacement therapy with oral or injectable testosterone results in wide fluctuations of serum hormone levels. More recently developed transdermal testosterone preparations allow stable physiological serum testosterone levels. Pulsatile GnRH administration can be used to stimulate spermatogenesis in men and ovulation in women with GnRH deficiency and normal gonadotropin secretion. Gonadotropin administration is indicated in cases of gonadotropin deficiency or GnRH resistance but is also an option, in alternative to pulsatile GnRH, for patients with defective GnRH secretion.

Cushing's disease, i.e., pituitary ACTH-secreting adenoma causing excess glucocorticoid secretion, is a rare disease with significant mortality and morbidity. Timely diagnosis and appropriate treatment can alter the course of the disease and are therefore mandatory. First step of the diagnostic work-up is the endogenous glucocorticoid excess by measurement of urinary free cortisol, cortisol circadian rhythmicity or suppression by low doses of dexamethasone. In patients with equivocal results, second line tests, such as the dexamethasone-suppressed CRH test and desmopressin stimulation, usually enable the diagnosis to be confirmed. Measurement of plasma ACTH then allows the distinction between ACTH-dependent (e.g., pituitary or extrapituitary neuroendocrine tumors) and ACTH-independent causes (e.g., adrenal tumors). The last step in the diagnostic algorithm is often the most fraught with problems as the distinction between Cushing's disease and ectopic ACTH secretion relies on judicious interpretation of several diagnostic procedures. Positive responses to stimulation with CRH and inhibition by high doses of dexamethasone, if concurrent, enable a pituitary origin to be established whereas conflicting results call for inferior petrosal sinus sampling, the latter to be performed in experienced centres only. Visualisation of the tumor at pituitary imaging is helpful but not required for the diagnosis, as microadenomas often remain undectected by MRI and/or CT scan and, on the other hand, visualisation of a non-secreting incidentaloma may be misleading. Surgical removal of the pituitary tumor is the optimal treatment choice and should be attempted in every patient. Surgical failures as well as relapses can be treated by radiotherapy, medical therapy or, if necessary, bilateral adrenalectomy. Finally, patients cured of Cushing's disease require long-term monitoring given the risk of relapse and clinical burden of associated ailments.

Acromegaly is a slowly progressive disease characterized by 30% increase of mortality rate for cardiovascular disease, respiratory complications and malignancies. The estimated prevalence of the disease is 40 cases/1000000 population with 3-4 new cases/1000000 population per year. The biochemical diagnosis is based upon the demonstration of high circulating levels of GH and IGF-I. A random GH level lower than 0.4 microg/l and an IGF-I value in the age- and sex-matched normal range makes the diagnosis of acromegaly unlikely. In doubtful cases, the lack of GH suppressibility below 1 microg/l (0.3 microg/l according to recent reports) after an oral glucose load will confirm the diagnosis. A pituitary adenoma is demonstrated in most cases by CT scan or MRI. A negative X-ray finding or the presence of empty sella do not exclude the diagnosis. Cardiovascular complications (acromegalic cardiomyopathy and arterial hypertension) should be looked for and, if present, followed-up by echocardiography and 24h-electrocardiogram. Sleep apnoea, when clinically suspicious, should be confirmed by polisomnography. At the moment of diagnosis all patients should undergo colonscopy. Lipid profile should be obtained and glucose tolerance evaluated. Surgery, radiotherapy and medical treatment represent the therapeutic options for acromegaly. The outcome of transsphenoidal surgery is far better for microadenomas (80-90%) than for macroadenomas (less than 50%), which unluckily represent more than 70% of all GH-secreting pituitary tumours. Therefore, pituitary surgery is the first line treatment for microadenomas. Medical therapy is based on GH-lowering drugs (somatostatin receptor agonists and, in some cases, dopaminergic agents) and GH receptor antagonists (pegvisomant). The former are traditionally indicated after unsuccessful surgery and while awaiting the effectiveness of radiation therapy. However, GH-lowering drugs are also used as primary therapy when surgery is contraindicated or in the case of large GH-secreting macroadenomas which are not likely to be completely removed by surgery. These compounds may also be indicated in the preoperative management of some acromegalic patients in order to lower the risk of surgical and anaesthetic complications. For the moment pegvisomant is indicated for patients resistant to the GH-lowering drugs and there is no evidence for drug-induced enlargement of the pituitary tumour. In order to avoid this possibility, however, a combination of pegvisomant and GH-lowering compound can also be conceived. With pegvisomant, IGF-I plasma levels are the marker of therapeutic efficacy and normalize in 97% of patients. Radiotherapy is employed sparingly due to the number of side effects (80% of hypopituitarism). It is indicated after unsuccessful surgical and/or medical treatment and allows the control of hormonal secretion and tumour growth in approx. 40% and 100% of cases, respectively. Acromegaly is defined as controlled when, in the absence of clinical activity, IGF-I levels are in the age- and sex-matched normal range and GH is normally suppressible by the oral glucose load.

Respiratory disorders are common and important complications in acromegaly. Patients suffering from acromegaly display a 1.6-3.3 fold increase in mortality rate, which is due to respiratory disorders in 25% of cases. In these patients, mortality for lung disease is 2-3 fold higher than in the general population. Every portion of the respiratory system may be involved. Deformities of facial bones, edema and hypertrophy of the mucosae and pharyngeal and laryngeal cartilages, enlargement of the tongue and inspiratory collapse of the hypopharinx, all may contribute to respiratory alterations. Nasal polyps, "hormonal rhinitis", changes of the voice and snoring are common occurrences. Though rarely, a laryngocele may ensue. Pneumomegaly is frequently observed and, as suggested by functional studies, might be due to an increased number rather than volume of the alveoli. An obstructive respiratory syndrome caused by mucosal thickening of the upper airways and bronchi is observed in 25% of female and 70% of male patients. The sleep apnea syndrome (SAS) affects 60-70% of acromegalic patients. SAS may be of obstructive, central or mixed type. Obstructive SAS is the prevailing form in acromegaly. It is due to intermittent obstruction of upper airways with preserved activity of the respiratory center, as testified by the remarkable thoracic and abdominal respiratory efforts. The pathogenesis of the central type of SAS is more complex. Narrowing of the upper airways may induce reflex inhibition of the respiratory center. Moreover, increased GH levels and, possibly, defects in the somatostatinergic pathways, may increase the ventilatory response of the respiratory center to carbon dioxide, thereby leading to respiratory arrest. In the mixed type of SAS, the phenomena underlying the other two forms coexist. Oxygen desaturation concomitant with the apneic episodes accounts for the frequent nocturnal wakening and diurnal drowsiness. Among the clinical correlates of SAS, arterial hypertension is of particular interest due to the close correlation existing between the two disorders. Sleep deprivation related to SAS seems per se to favor the appearance of hypertension. Moreover, short lasting hypoxemia may induce prolonged elevations of blood pressure, mediated by decreased endothelial generation of nitric oxide. Thus, since cardiovascular events are the main cause of mortality in patients with acromegaly, it is reasonable to hypothesize that SAS is involved in the reduced life span of these patients.