Mirella Moro

Elastosonographic evaluation of thyroid nodules in acromegaly

OBJECTIVE Ultrasound-elastography (US-E) appears to be a helpful tool for the diagnosis of thyroid cancer. In acromegaly, the prevalence of thyroid cancer is still debated. The aims of this study were to evaluate thyroid nodules in acromegaly and to establish the accuracy of US-E in providing information on their nature, using cytological analysis as a reference. SUBJECTS AND METHODS US-E was applied to 90 nodules detected in 25 acromegalic patients and to 94 nodules found in 31 non-acromegalic goitrous subjects. The lesions were classified according to the elasticity scores (ES) as soft (ES 1-2) or hard (ES 3-4). Fine needle aspiration cytology could be performed in 60.8% of hard nodules in acromegalics and in 86.7% of hard nodules in controls. RESULTS The prevalence of hard nodules was significantly higher in the whole group of acromegalic patients than in controls (56.8 vs 16.0%, P<0.0001). The prevalence of hard nodules in patients with active acromegaly (68.9%) was greater, though not to a statistically significant extent, than that observed in cured (44.4%) and controlled (52.5%) patients. Cytology revealed malignancy or suspect malignancy in four of the nodules of non-acromegalic subjects and in none of the nodules of acromegalic patients. CONCLUSIONS This study has demonstrated a high prevalence of stiff thyroid nodules in acromegaly, greater than that found in non-acromegalic goitrous subjects. In acromegalics, hard nodules appeared not to be malignant on cytopathological examination and are probably of fibrous nature. Thus, US-E appears to be of limited value for the diagnosis of thyroid cancer in acromegaly.

A frequent oligogenic involvement in congenital hypothyroidism

Congenital hypothyroidism (CH), the most frequent form of preventable mental retardation, is predicted to have a relevant genetic origin. However, CH is frequently reported to be sporadic and candidate gene variations were found in <10% of the investigated patients. Here, we characterize the involvement of 11 candidate genes through a systematic Next Generation Sequencing (NGS) analysis. The NGS was performed in 177 unrelated CH patients (94 gland-in-situ; 83 dysgenesis) and in 3,538 control subjects. Non-synonymous or splicing rare variants (MAF < 0.01) were accepted, and their functional impact was predicted by a comprehensive bioinformatic approach and co-segregation studies. The frequency of variations in cases and controls was extended to 18 CH-unrelated genes. At least one rare variant was accepted in 103/177 patients. Monogenic recessive forms of the disease were found in five cases, but oligogenic involvement was detected in 39 patients. The 167 variations were found to affect all genes independently of the CH phenotype. These findings were replicated in an independent cohort of additional 145 CH cases. When compared to 3,538 controls, the CH population was significantly enriched with disrupting variants in the candidate genes (P = 5.5 × 10-7), but not with rare variations in CH-unrelated genes. Co-segregation studies of the hypothyroid phenotype with multiple gene variants in several pedigrees confirmed the potential oligogenic origin of CH. The systematic NGS approach reveals the frequent combination of rare variations in morphogenetic or functional candidate genes in CH patients independently of phenotype. The oligogenic origin represents a suitable explanation for the frequent sporadic CH occurrence.

The diagnosis of GH deficiency in obese patients: a reappraisal with GHRH plus arginine testing after pharmacological blockade of lipolysis

BACKGROUND The diagnosis of GH deficiency (GHD) in obese patients is complicated by the reduced GH secretion associated with overweight. A GH response to GHRH+arginine lower than 4.2 microg/l is currently considered indicative of GHD in obesity. The aim of the study was to investigate the effect of acute pharmacological blockade of lipolysis on the GH response to GHRH+arginine in obese patients. PATIENTS AND METHODS Two groups of patients were studied: 12 obese patients with proven GHD and 14 patients with essential obesity. On separate occasions, two tests were carried out in each patient: GHRH+arginine and GHRH+arginine preceded by acipimox. RESULTS The mean GH peak after GHRH+arginine was significantly lower in hypopituitary patients than in subjects with essential obesity. Acipimox significantly increased the mean GH response in patients with essential obesity, but not in hypopituitary subjects. All hypopituitary patients and 7/14 patients with essential obesity displayed GH peaks lower than 4.2 microg/l after GHRH+arginine: the GH response to the test increased after acipimox pretreatment in five of these seven essentially obese subjects. After acipimox administration, free fatty acids (FFAs) significantly fell in both groups with comparable mean absolute decreases. All IGF1 values were normal in both groups of subjects. CONCLUSIONS Our study has demonstrated that the acipimox-induced acute reduction of circulating FFA levels increases mean somatotropin response to GHRH+arginine in patients with essential obesity, whereas it has no effect in hypopituitary subjects. The current criterion for the diagnosis of GHD in obese patients may be misleading. Indeed, subjects affected by third degree obesity, like most of our patients, may be erroneously classified as really GH-deficient and started on an expensive unjustified treatment. It appears therefore that the current criteria for the diagnosis of GHD in obesity should be reconsidered in the light of further studies also taking into account different body mass index groups.

Thyroid nodules in acromegaly: The role of elastography

INTRODUCTION Ultrasound elastography (US-E) is a helpful tool for the diagnosis of thyroid cancer. In acromegaly, multinodular goiter is a common occurrence while the prevalence of thyroid cancer is still matter of debate. Our aims were to evaluate thyroid nodules in acromegaly and to assess the accuracy of US-E in providing information on their nature (benign vs. malignant) using cytological analysis as a reference. MATERIALS AND METHODS US-E was performed in 25 patients with acromegaly (active in 10 cases, medically controlled in 8, and cured by pituitary surgery in 7), each of whom had at least one solid thyroid nodule. A total of 90 nodules were classified according to the elastography scores (ES): ES1 and ES2 for soft nodules, ES3 and ES4 for an elastic lesions. FNAC was performed in 78.6% of the ES 4 lesions and 54.1% of the ES 3 nodules. RESULTS Fourteen of the 90 nodules (15.5%) displayed an ES of 1, 25 (27.7%) an ES of 2, 37 (41.3%) an ES of 3, and 14 (15.5%) an ES of 4. The prevalence of hard nodules in patients with active acromegaly (68.9%) was greater than that observed in patients with cured (44.4%) or controlled (52.5%) acromegaly. The prevalence of hard nodules in the total series (56.7%) was higher than that reported in nonacromegalic goitrous subjects. All thyroid nodules subjected to FNAC were negative for malignant cells and follicular lesions. DISCUSSION Acromegaly (particularly active forms) is associated with a high prevalence of stiff thyroid nodules that exceeds that observed in nonacromegalic patients with goiters (33.7%). However, these nodules were never malignant at cytology, and their firmness is probably due to fibrosis. US-E therefore appears to be of limited value for the diagnosis of thyroid cancer in patients with acromegaly.

Chronic Treatment With Parlodel LAR® of Patients With Prolactin-Secreting Tumours: Different Responsiveness of Micro-and Macroprolactinomas

UNLABELLED Forty-one patients with prolactinoma (25 micro-, 16 macroprolactinomas) were treated with a long-acting injectable preparation of bromocriptine (Parlodel LAR, Sandoz), 25-100 mg (mostly 50 mg) in every 4-8 weeks for as long as 43 months (median 19 months). The first injection caused a prompt fall of plasma PRL which reached its nadir value after 3 days. Thereafter, hormone levels remained well below initial values for 4 weeks or longer, though with the tendency, more pronounced in microprolactinoma patients, to rise again toward baseline. The prevalence of PRL normalization was greater in the macro- than in the microprolactinoma group. By repeated injections plasma PRL could be kept close to or within the normal limits in most of the patients. However, the extent of PRL inhibition was significantly greater in macro- than in microprolactinoma patients (p less than 0.01). Clinical improvement occurred in the majority of the patients, shrinkage of the tumour in 50% of them. Adverse reactions were generally mild or of moderate severity and subsided spontaneously in 24 h. They were less frequent (NS) and less severe (p less than 0.05) in macro- than in microprolactinoma patients. IN CONCLUSION a. injectable bromocriptine (Parlodel LAR) is a highly effective preparation particularly suitable for the long-term treatment of tumourous hyperprolactinemia; b. patients with macroprolactinoma exhibit, compared with microprolactinoma patients, better responsiveness and better tolerability to injectable bromocriptine.