Bruno Ambrosi

We describe a patient affected by Cushing's disease due to the presence of double pituitary adenomas, one located within the anterior pituitary and the other in the infundibulum associated with a remnant of Rakthe's pouch. Cure was achieved only after the infundibulum lesion was surgically removed. A 38-year-old female presented with unexplained weight gain, hirsutism, amenorrhea, asthenia, recurrent cutaneous micotic infections and alopecia. Hormonal studies indicated Cushing's disease and MRI showed an enlarged pituitary gland with a marked and homogeneous enhancement after injection of gadolinium and an enlarged infundibulum with a maximum diameter of 8 mm. As a venous sampling of the inferior petrosal sinus after 10 μg iv desmopressin stimulation revealed a central to peripheral ACTH ratio consistent with a pituitary ACTH-secreting tumor, transphenoidal explorative surgery was performed and a 4-mm pituitary adenoma immunopositive for ACTH was disclosed and removed. Since postoperative hormonal evaluation showed persistent hypercortisolism, confirmed by dynamic tests, the patient again underwent surgery by transcranial access and the infundibulum mass was removed. Histology and immunochemistry were consistent with an ACTH-secreting adenoma. A few months after the second operation, cushingoid features were significantly reverted and symptoms improved. Although Cushing's patients bearing multiple adenomas have already been documented, the presence of two adenomas both immunohistochemically positive for ACTH is a very rare cause of Cushing's disease and this is the first report of a case of double ACTH-producing adenomas, one located in the pituitary gland and one attached to the stalk.

Introduction: The need of a long-term follow-up in adrenal incidentalomas (AI) is debated and data on cardiovascular events (CVE) are lacking. Methods: In this retrospective study all patients referred to seven Italian Endocrine Centers for AI, without signs of hypercortisolism at baseline and with a ≥5 years follow-up (80.7±30 months, range 60–286), were enrolled. From 171 patients (121 F) aged 59.5±10.2 years (range 25–79) the changes in weight, glucose and lipid metabolism, blood pressure control and the occurrence of CVE were obtained. Patients were classified as affected with subclinical hypercortisolism (SH) in the presence of cortisol after 1-mg dexamethasone suppression (1-mg DST) test >5 μg/dl or ≥2 parameters out of low ACTH, increased urinary free cortisol and 1-mg DST >3 μg/dl. Results: At baseline SH was found in the 14% of patients. The prevalence of obesity, diabetes mellitus, dyslipidemia, and arterial hypertension (54, 21, 25, and 45% respectively) was not different between patients with (SH+) and without SH (SH−). At baseline SH+ patients showed a higher CVE prevalence than SH− ones (21 vs 7%), regardless of age (OR 3.3, 95% CI 1.0–11.1, P2.5 cm in the 2.9% of cases. The glucose and lipid metabolism, blood pressure, and weight control worsened in the 24, 16, 36 and 14% of patients, respectively. The SH persistence/appearance was significantly associated with the worsening of ≥2 out of the metabolic parameters (P=0.013) and with the occurrence of new CVE (P=0.05). Conclusion: In AI patients a long-term follow-up is recommended for the diameter increase and SH development risk. SH patients are at risk of worsening of the metabolic control and, importantly, of CVE.

A highly polymorphic microsatellite in the IGF-I gene promoter composed of variable cytosine–adenine (CA) repeats (n=10–24) has been linked to IGF-I levels, risk of diabetes and cardiovascular diseases with conflicting results. Aim of this study was to investigate the impact of this polymorphism on the response to rhGH (mean dose 0.34±0.14 mg/day) in adult GH-deficient (GHD) patients after 1 (n=98) and 5 (n=50) years. Different genotypes were studied by microsatellite method, according to the most frequent 192 bp allele (19 CA repeats) subjects were divided into three groups: homozygous (192/192, n=38), heterozygous (192/X, n=44) and non-carriers (X/X, n=16). Allelic distribution was similar in the subgroup followed for 5 years. The genotype did not influence neither the phenotype of patients at baseline (including IGF-I levels), nor their response to rhGH in terms of decrease in BF% and increase in IGF-I levels. Conversely, after 1 year, there was a significant worsening of insulin sensitivity, documented by increase in fasting glucose levels and HOMA-IR (from 81±8 to 86±8 mg/dl and from 1.7±1.0 to 2.4±1.6 respectively, PP<0.001) only in homozygous. During long-term treatment, HOMA-IR restored to basal values in all patients, though fasting glucose levels remained higher than at baseline in homozygous. The decrease in total and LDL-cholesterol was significant both in homozygous and in heterozygous, but not in non-carriers. No difference among groups was observed in rhGH dose throughout study. In conclusion, the presence of the wild-type allele in the IGF-I gene promoter might increase sensitivity to metabolic changes induced by rhGH, either negative or positive. In the long-term, beneficial effects (i.e. persistent BF% reduction) may overcome the negative impact on glucose metabolism regardless IGF-I genotype, while positive effects on lipid profile manifest in patients carrying at least one 192 bp allele.

Objective: Effects of GH replacement in patients with GH deficiency (GHD) after a cure for acromegaly so far have been poorly studied, although its prevalence among acromegalic patients may reach the 60%. The aim of the study was to evaluate whether metabolic parameters and quality of life are improved by GH replacement in patients with prior acromegaly and severe GHD. Design and Methods: This was a prospective study on 42 GHD subjects [22 men, mean age (sd): 48 ± 10]: 10 acromegalics treated with recombinant human GH (group A), 12 acromegalics who refused treatment (group B), and 20 subjects operated for nonfunctioning pituitary adenoma on recombinant human GH (group C). Serum IGF-I levels, lipid profile, glucose levels (fasting and after an oral glucose tolerance test), glycosylated hemoglobin, insulin resistance (homeostasis model assessment insulin resistance index), anthropometric parameters (body mass index, waist circumference, body composition), and quality of life (Questions on Life Satisfaction-Hypopituitarism Z-scores) were evaluated at baseline and after 12 and 36 months. Results: At baseline, group B showed higher IGF sd score than group A and C, as well as better quality of life and higher post-oral glucose tolerance test glucose levels than group A. After 12-months, similarly in group A and C, the IGF-I sd score significantly increased, and body composition and lipid profile improved, without deterioration of glucose tolerance. Quality of life significantly improved too, and the baseline difference between group A and B disappeared. Results were confirmed after 36 months. Conclusions: In GHD acromegalic patients, GH therapy improved body composition, lipid profile, and quality of life as in patients with GHD due to nonfunctioning pituitary adenoma, without negative effects on glucose metabolism. GH replacement therapy should be considered in these patients, as in patients with GHD from other causes.

Wnt/beta-catenin pathway has been shown to be upregulated in parathyroid carcinomas due to CDC73/HRPT2 gene inactivating mutations and loss of parafibromin and APC. Wnt/beta-catenin signalling has been identified as a crucial upstream regulator of TBX1 gene expression in a mouse model of DiGeorge syndrome (DGS). We tested the hypothesis that the embryonic transcription factor TBX1, involved in cell differentiation during parathyroid organogenesis, might be a target of the beta-catenin accumulation in parathyroid cancers. By Real-Time PCR, western blot and immunohistochemistry, we demonstrated that TBX1 mRNA and protein were expressed at high levels in 23 typical parathyroid adenomas showing a clearly positive staining in parathyroid PTH+ cells with a cytoplasmic and nuclear localization. A similar expression pattern could be detected in parafibromin-expressing parathyroid cancers (n=3). By contrast, TBX1 mRNA and protein were definitely downregulated in parafibromin negative parathyroid carcinomas (n=14) and in 3 metastatic lesions, suggesting that Wnt/beta-catenin activation might inhibit TBX1 expression. Functional studies were performed in HEK293 cells, since they expressed TBX1 mRNA and protein. In HEK293 cells TBX1 mRNA and protein were inhibited by beta-catenin accumulation induced by 24-hours treatment with 1-20 nM lithium chloride, while beta-catenin degradation induced by pretreatment with 10-100 nM calyculin for 40 min determined an increase in TBX1 expression levels. Moreover, the activation of the calcium sensing receptor (CaSR) by stimulating HEK293 cells stably transfected with the human CaSR, with increasing calcium concentrations as well as with increasing concentrations of the potent and selective CaSR agonist R-568, induced a significant reduction in TBX1 mRNA levels after 24 hours incubation. Nonetheless, in human adult normal parathyroid tissues (n=3), TBX1 protein was expressed in endothelial CD31+, alfa-SMA+ cells while parathyroid chief cells were negative. During embryonic development impaired TBX1 gene dosage, both deletion and duplication, is associated to DGS phenotype: further studies will investigate the effect of the beta-catenin accumulation induced inhibition on TBX1 expression in parathyroid cancers. In conclusion, the present study: 1) identified a new target of the Wnt/beta-catenin pathways in parathyroid tumors and 2) suggested that TBX1 impaired expression contributes to parathyroid tumorigenesis. Nothing to Disclose: SC, CV, VV, MM, MB, AT, VG, AS, LV, FC, SF, MF, EC, BA, YT, SB, AS

Background and aims: It is recognized that overt thyroid dysfunction is associated with weight changes, but the influence of a minor alteration of thyroid function remains unclear. This study aimed to further investigate the relationship between obesity and thyroid function and to examine the possible role of insulin resistance on the hypothalamic-pituitary-thyroid axis. Methods and results: Serum TSH and free T₄ (FT₄) levels, anthropometric and metabolic parameters were evaluated in 581 obese patients. In all patients TSH values progressively increased according to the severity of obesity and were positively correlated with body mass index (p=0.001, r=0.13) and waist circumference (p=0.02, r=0.11). Patients with insulin resistance showed higher TSH (1.8±1.0 vs 1.6±0.9 μUI/l; p=0.03) and lower FT₄ levels (13.8±2.3 vs 15.0±2.2 pmol/l; pppp4 was negatively associated with fasting insulin (pppConclusions: A relationship between thyroid function and overweight/obesity condition seems to exist, mainly influenced by insulin resistance. Whether variations in TSH and/or thyroid hormones, within a normal range, can influence body weight or whether obesity per se can alter thyroid function cannot be stated so far. Further studies are needed to assess the link between thyroid function and body weight, by considering not only changes in thyroid hormones, but also body fat distribution, obesity duration and low-grade inflammation.

Objective: While left ventricular (LV) dysfunction has been described in patients with Cushing’s syndrome (CS), data concerning morphologic and functional cardiac alterations in patients with incidentally discovered adrenal masses [adrenal “incidentaloma” (AI)], without overt hypercortisolism, are lacking. In this study the echocardiographic characteristics of patients with AI were evaluated and then compared with those of lean and obese normotensive subjects. Subjects and methods: Twenty-one patients with AI, without clinical or subclinical hypercortisolism, 18 normotensive obese subjects matched for gender and body mass index (BMI) and 20 normotensive lean subjects were studied. Echocardiography was performed in all subjects. In all patients plasma ACTH, serum cortisol, and DHEA-S levels were measured. Results: Patients with AI showed greater impairment of several echocardiographic indices of LV hypertrophy and diastolic dysfunction compared to normotensive lean subjects (pppppConclusion: In patients with non-functioning AI there is an impairment of cardiac morphology and function. These data suggest that patients with AI should be carefully screened also by means of echocardiographic studies.