Italian Guidelines for the Management of Non-Functioning Benign and Locally Symptomatic Thyroid Nodules

AIM

This guideline (GL) is aimed at providing a reference for the management of non-functioning, benign thyroid nodules causing local symptoms in adults outside of pregnancy.

METHODS

This GL has been developed following the methods described in the Manual of the National Guideline System. For each question, the panel appointed by Associazione Medici Endocrinology (AME) identified potentially relevant outcomes, which were then rated for their impact on therapeutic choices. Only outcomes classified as "critical" and "important" were considered in the systematic review of evidence and only those classified as "critical" were considered in the formulation of recommendations.

RESULTS

The present GL contains recommendations about the respective roles of surgery and minimally invasive treatments for the management of benign symptomatic thyroid nodules. We suggest hemithyroidectomy plus isthmectomy as the first-choice surgical treatment, provided that clinically significant disease is not present in the contralateral thyroid lobe. Total thyroidectomy should be considered for patients with clinically significant disease in the contralateral thyroid lobe. We suggest considering thermo-ablation as an alternative option to surgery for patients with a symptomatic, solid, benign, single, or dominant thyroid nodule. These recommendations apply to outpatients, either in primary care or when referred to specialists.

CONCLUSION

The present GL is directed to endocrinologists, surgeons, and interventional radiologists working in hospitals, in territorial services, or private practice, general practitioners, and patients. The available data suggest that the implementation of this GL recommendations will result in the progressive reduction of surgical procedures for benign thyroid nodular disease, with a decreased number of admissions to surgical departments for non-malignant conditions and more rapid access to patients with thyroid cancer. Importantly, a reduction of indirect costs due to long-term replacement therapy and the management of surgical complications may also be speculated.

Hemithyroidectomy and ipsilateral central neck dissection for T1 low-risk papillary thyroid cancer: single-institution retrospective observational study

OBJECTIVE

The aim of this study was to report the rationale and selection criteria for hemithyroidectomy and ipsilateral central neck dissection in patients with selected papillary thyroid cancer and to report the surgical and oncological outcomes.

DESIGN

Single-institution retrospective observational study.

METHODS

The clinical records of patients with a histopathological diagnosis of low-risk pT1 papillary thyroid cancer who underwent hemithyroidectomy with or without ipsilateral central neck dissection between March 2000 and April 2018 at a tertiary referral center were retrospectively reviewed. Demographic, clinical, and histopathological data were collected.

RESULTS

During the study period, 176 patients underwent hemithyroidectomy for PTC. Thirteen patients (13/176, 7.39%) were lost to follow-up and 74 patients (74/163 45.40%) underwent completion thyroidectomy within 1 month because they were classified intermediate ATA initial risk based on definitive pathology. The final study group was composed of 89 patients, who had a median follow-up of 5.3 years. The mean follow-up was 6.3 years (range: 36-207 months). Eighty-four patients (94.38%) did not experience recurrence in the follow-up period. A total of 5/89 patients (5.62%) underwent delayed completion thyroidectomy with or without neck dissection for recurrent malignancy in the residual lobe (3/5) or regional lymph nodes (2/5). The median time from surgery to recurrence was 24.8 months (range: 6-60). The follicular variant was an independent risk factor for recurrence.

CONCLUSIONS

Hemithyroidectomy with or without prophylactic ipsilateral central neck dissection is a valuable treatment option in selected low-risk papillary thyroid cancers and ensures a low risk of recurrence. Prophylactic ipsilateral central compartment dissection could have a role in improving cancer staging, and accurate ultrasonographic follow-up is essential to identify local recurrence.

Italian Association of Clinical Endocrinologists (AME) and International Chapter of Clinical Endocrinology (ICCE). Position statement for clinical practice: prolactin-secreting tumors

Prolactinomas are the most frequent pituitary adenomas. Prolactinoma may occur in different clinical settings and always require an individually tailored approach. This is the reason why a panel of Italian neuroendocrine experts was charged with the task to provide indications for the diagnostic and therapeutic approaches that can be easily applied in different contexts. The document provides 15 recommendations for diagnosis and 54 recommendations for treatment, issued according to the GRADE system. The level of agreement among panel members was formally evaluated by RAND-UCLA methodology. In the last century, prolactinomas represented the paradigm of pituitary tumors for which the development of highly effective drugs obtained the best results, allowing to avoid neurosurgery in most cases. The impressive improvement of neurosurgical endoscopic techniques allows a far better definition of the tumoral tissue during surgery and the remission of endocrine symptoms in many patients with pituitary tumors. Consequently, this refinement of neurosurgery is changing the therapeutic strategy in prolactinomas, allowing the definitive cure of some patients with permanent discontinuation of medical therapy.

Postoperative hypoparathyroidism after completion thyroidectomy for well-differentiated thyroid cancer

OBJECTIVE

Thyroid surgery may lead to postoperative complications. The aim of this paper was to determine whether the rate of postoperative hypoparathyroidism (HPT) is influenced by whether surgery is staged.

DESIGN

Single-institution retrospective observational study.

METHODS

The clinical records of 786 patients treated at the Otolaryngology Unit of the Azienda USL-IRCCS di Reggio Emilia between January 1990 and December 2015 were reviewed. Patients were divided into two groups according to the surgical treatment received: group TT (637 patients, 81.04%) underwent single-stage total thyroidectomy; Group cT (149 patients, 18.96%) underwent loboisthmusectomy and delayed completion total thyroidectomy. Transient and permanent HPT, assessed after 6 months of follow-up, were the primary endpoints. Risk factors of postoperative HPT were also analysed as secondary outcomes.

RESULTS

Rates of transient HPT in group TT were higher than those observed in group cT, (P = 0.0057). Analysis of risk factors identified sex as an independent risk factor for transient HPT only for group TT (P = 0.0012) and the number of parathyroid glands remaining in situ (PGRIS) as an independent risk factor for transient and permanent HPT for group TT (P < 0.0001 and P = 0.0002, respectively).

CONCLUSIONS

This study suggests that the risk of transient postoperative HPT is lower in patients that undergo completion thyroidectomy. Further independent risk factors for postoperative HPT are female sex and PGRIS score. In light of the growing use of conservative surgery for thyroid neoplasms, these findings could help to adequately plan surgery in order to reduce endocrine complications.

Exploring the Inter-observer Agreement Among the Members of the Italian Consensus for the Classification and Reporting of Thyroid Cytology

Classification schemes for reporting thyroid cytology of fine needle aspiration (FNA) of thyroid nodules are largely used in clinical practice, but the level of inter-observer agreement among cytopathologists is poorly acknowledged. The present study aimed to explore the inter-observer agreement among the experienced authors of the 2014 Italian Consensus for Classification and Reporting of Thyroid Cytology (ICCRTC). A stratified randomization was performed in order to obtain a sample homogeneously distributed and representative of all ICCRTC classes. Four high-experience raters were randomly selected among the extensors of the Italian consensus. They independently reviewed 60 FNA samples blindly of the initial cytological report and clinical features. Their overall agreement was evaluated according to Fleiss' kappa. The overall inter-observer agreement was moderate (κ 0.46). Specifically, a good agreement was found when the samples were consistent for malignancy (TIR5) or were not adequate for diagnosis (TIR1) (κ 0.67 and κ 0.73, respectively). A moderate agreement was present for suspicious-for-malignant category (TIR4), and a fair agreement was recorded in the two intermediate ones (TIR3A and TIR3B) (κ 0.36 and κ 0.35, respectively). For clinical purposes, the agreement was good (κ 0.74) in differentiating cases with surgical indication (TIR4/TIR5) from those in which surgery is not essential or requires limited extension (TIR3B/TIR3A/TIR2). In conclusion, the present study confirms the reliability of ICCRTC. These data represent a reference for cytopathologists using this system and are useful for the practice of clinicians and surgeons.

Italian Association of Clinical Endocrinologists (AME) and Italian AACE Chapter Position Statement for Clinical Practice: Acromegaly - Part 1: Diagnostic and Clinical Issues

Acromegaly is a rare disease. Improvements in lifespan in these patients have recently been reported due to transsphenoidal surgery (TSS), advances in medical therapy, and strict criteria for defining disease remission. This document reports the opinions of a group of Italian experts who have gathered together their prolonged clinical experience in the diagnostic and therapeutic challenges of acromegaly patients. Both GH and IGF-I (only IGF-I in those treated with Pegvisomant) are needed in the diagnosis and follow-up. Comorbidities (cardio-cerebrovascular disease, sleep apnea, metabolic derangement, neoplasms, and bone/joint disease) should be specifically addressed. Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas.

Italian Association of Clinical Endocrinologists (AME) and Italian AACE Chapter Position Statement for Clinical Practice: Acromegaly - Part 2: Therapeutic Issues

Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas. The therapeutic management of acromegaly always requires a personalized strategy. Normal age-matched IGF-I values are the treatment goal. Transsphenoidal surgery by an expert neurosurgeon is the primary treatment modality for most patients, especially if there are neurological complications. In patients with poor clinical conditions or who refuse surgery, primary medical treatment should be offered, firstly with somatostatin analogs (SSAs). In patients who do not reach hormonal targets with first-generation depot SSAs, a second pharmacological option with pasireotide LAR or pegvisomant (alone or combined with SSA) should be offered. Irradiation could be proposed to patients with surgical remnants who would like to be free from long-term medical therapies or those with persistent disease activity or tumor growth despite surgery or medical therapy. Since the therapeutic tools available enable therapeutic targets to be achieved in most cases, the challenge is to focus more on the quality of life.

Italian Association of Clinical Endocrinologists (AME) and Italian AACE Chapter Position Statement for Clinical Practice: Assessment of Response to Treatment and Follow-Up in Gastroenteropancreatic Neuroendocrine Neoplasms

Well-established criteria for evaluating the response to treatment and the appropriate followup of individual patients are critical in clinical oncology. The current evidence-based data on these issues in terms of the management of gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN) are unfortunately limited. This document by the Italian Association of Clinical Endocrinologists (AME) on the criteria for the follow-up of GEP-NEN patients is aimed at providing comprehensive recommendations for everyday clinical practice based on both the best available evidence and the combined opinion of an interdisciplinary panel of experts. The initial risk stratification of patients with NENs should be performed according to the grading, staging and functional status of the neoplasm and the presence of an inherited syndrome. The evaluation of response to the initial treatment, and to the subsequent therapies for disease progression or recurrence, should be based on a cost-effective, risk-effective and timely use of the appropriate diagnostic resources. A multidisciplinary evaluation of the response to the treatment is strongly recommended and, at every step in the follow-up, it is mandatory to assess the disease state and the patient performance status, comorbidities, and recent clinical evolution. Local expertise, available technical resources and the patient preferences should always be evaluated while planning the individual clinical management of GEP-NENs.

Italian Association of Clinical Endocrinologists (AME) and Italian Chapter of the American Association of Clinical Endocrinologists (AACE) Position Statement: Clinical Management of Vitamin D Deficiency in Adults

Vitamin D deficiency is very common and prescriptions of both assay and supplementation are increasing more and more. Health expenditure is exponentially increasing, thus it is timely and appropriate to establish rules. The Italian Association of Clinical Endocrinologists appointed a task force to review literature about vitamin D deficiency in adults. Four topics were identified as worthy for the practicing clinicians. For each topic recommendations based on scientific evidence and clinical practice were issued according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) System. (1) What cut-off defines vitamin D deficiency: even though 20 ng/mL (50 nmol/L) can be considered appropriate in the general population, we recommend to maintain levels above 30 ng/mL (75 nmol/L) in categories at risk. (2) Whom, when, and how to perform screening for vitamin D deficiency: categories at risk (patients with bone, liver, kidney diseases, obesity, malabsorption, during pregnancy and lactation, some elderly) but not healthy people should be screened by the 25-hydroxy-vitamin D assay. (3) Whom and how to treat vitamin D deficiency: beyond healthy lifestyle (mostly sun exposure), we recommend oral vitamin D (vitamin D2 or vitamin D3) supplementation in patients treated with bone active drugs and in those with demonstrated deficiency. Dosages, molecules and modalities of administration can be profitably individually tailored. (4) How to monitor the efficacy of treatment with vitamin D: no routine monitoring is suggested during vitamin D treatment due to its large therapeutic index. In particular conditions, 25-hydroxy-vitamin D can be assayed after at least a 6-month treatment. We are confident that this document will help practicing clinicians in their daily clinical practice.

Long-term outcomes of central neck dissection for cN0 papillary thyroid carcinoma

OBJECTIVE

The risk-benefit ratio of central neck dissection (CND) in patients affected by papillary thyroid carcinoma (PTC) without clinical or ultrasonographic (US) evidence of neck lymph node metastasis (cN0) is currently debated. The aim of this study was to evaluate long-term outcome of CND on locoregional recurrence, distant metastasis, survival, and postoperative complications in a large series of patients with cN0-PTC.

STUDY DESIGN

Observational retrospective controlled study.

METHODS

Clinical records of patients (n=610) surgically treated for cN0-PTC at the Otolaryngology Unit of the Arcispedale Santa Maria Nuova-IRCCS, Reggio Emilia, Italy, from January 1984 to December 2008, were retrospectively reviewed. Study population was divided into three groups according to surgical treatment: Group A, total thyroidectomy (n=205); Group B, total thyroidectomy and elective ipsilateral CND (n=281); Group C, total thyroidectomy and bilateral CND (n=124).

RESULTS

Of a total of 610 patients, 305 (50%) were classified as low-risk, 278 (45.57%) as intermediate-risk, and 27 (4.43%) as high-risk. Response to initial therapy was excellent in 567 patients (92.95%), acceptable in 21 (3.44%), and incomplete in 22 (3.61%), with no significant differences among groups. Locoregional recurrence was detected in 32 (5.2%) out of 610 patients. Distant metastasis was found in 15 patients (2.5%). Statistical analysis showed no significant differences in the rates of locoregional recurrence (p=0.890) or distant metastasis (p=0.538) among groups. Disease-specific mortality and overall survival did not significantly differ among groups (p=0.248 and 0.223, respectively). Rate of permanent hypoparathyroidism was significantly higher in Group C patients compared to those in Groups A and B.

CONCLUSION

CND does not confer any clear advantage in the treatment of low-risk patients, regardless of surgical procedure. Instead, bilateral CND may be effective in limiting disease relapse and/or progression in patients at higher prognostic risk. Our data indicate that elective CND does not confer any clear advantage in terms of locoregional recurrence and long-term survival, as demonstrated by outcomes of the study Groups, regardless of their different prognostic risk. Elective CND allows a more accurate pathologic staging of central neck lymph nodes, despite its increasing the risk of permanent hypoparathyroidism. Intraoperative pathologic staging is a valuable tool to assess the risk of controlateral lymph node metastasis in the central neck compartment and to limit more aggressive surgery only to cases, otherwise understaged, with lymph node metastasis.

Critical Pitfalls in the use of BRAF Mutation as a Diagnostic Tool in Thyroid Nodules: a Case Report

Thyroid fine-needle aspiration (FNA) cytology is the primary tool for the diagnostic evaluation of thyroid nodules. BRAF mutation analysis is employed as an ancillary tool in indeterminate cases, as recommended by the American Thyroid Association management guidelines. Hereby, we report the case of a 73-year-old woman who presented an 8-mm-size, ill-defined, left thyroid nodule. FNA resulted "suspicious for papillary thyroid carcinoma". BRAF mutation status was analyzed, and somatic BRAF (V600E) mutation identified. The patient underwent a total thyroidectomy. At histological examination, the nodule was composed of Langerhans cells, admixed with many eosinophils. A final diagnosis of Langerhans cell histiocytosis of the thyroid was made. Our case emphasizes the critical diagnostic pitfalls due to the use of BRAF (V600E) mutation analysis in thyroid FNA. Notably, BRAF (V600E) mutation is common in melanoma, colorectal carcinoma, lung carcinoma, ovarian carcinoma, brain tumors, hairy cell leukemia, multiple myeloma, and histiocytoses. Therefore, in cases of indeterminate FNA with unclassifiable atypical cells BRAF (V600E) mutated, the possibility of a localization of hystiocytosis or a secondary thyroid malignancy should be taken into account.

ITALIAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS STATEMENT-REPLACEMENT THERAPY FOR PRIMARY HYPOTHYROIDISM: A BRIEF GUIDE FOR CLINICAL PRACTICE

OBJECTIVE

Hypothyroidism requires life-long thyroid hormone replacement therapy in most patients. Oral levothyroxine (LT4) is an established safe and effective treatment for hypothyroidism, but some issues remain unsettled.

METHODS

The Italian Association of Clinical Endocrinologists appointed a panel of experts to provide an updated statement for appropriate use of thyroid hormone formulations for hypothyroidism replacement therapy. The American Association of Clinical Endocrinologists' protocol for standardized production of clinical practice guidelines was followed.

RESULTS

LT4 is the first choice in replacement therapy. Thyroid-stimulating hormone (TSH) should be maintained between 1.0 and 3.0 mIU/L in young subjects and at the upper normal limit in elderly or fragile patients. Achievement of biochemical targets, patient well-being, and adherence to treatment should be addressed. In patients with unstable serum TSH, a search for interfering factors and patient compliance is warranted. Liquid or gel formulations may be considered in subjects with hampered LT4 absorption or who do not allow sufficient time before or after meals and LT4 replacement. Replacement therapy with LT4 and L-triiodothyronine (LT3) combination is generally not recommended. A trial may be considered in patients with normal values of serum TSH who continue to complain of symptoms of hypothyroidism only after co-existent nonthyroid problems have been excluded or optimally managed. LT3 should be administered in small (LT4:LT3 ratio, 10:1 to 20:1) divided daily doses. Combined therapy should be avoided in elderly patients or those with cardiac risk factors and in pregnancy.

CONCLUSION

LT4 therapy should be aimed at resolution of symptoms of hypothyroidism, normalization of serum TSH, and improvement of quality of life. In selected cases, the use of liquid LT4 formulations or combined LT4/LT3 treatment may be considered to improve adherence to treatment or patient well-being.

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists FT3 = free triiodothyronine FT4 = free thyroxine LT3 = levotriiodothyronine LT4 = levothyroxine MeSH = medicine medical subject headings QoL = quality of life TSH = thyroid-stimulating hormone.

Italian association of clinical endocrinologists (AME) position statement: drug therapy of osteoporosis

Treatment of osteoporosis is aimed to prevent fragility fractures and to stabilize or increase bone mineral density. Several drugs with different efficacy and safety profiles are available. The long-term therapeutic strategy should be planned, and the initial treatment should be selected according to the individual site-specific fracture risk and the need to give the maximal protection when the fracture risk is highest (i.e. in the late life). The present consensus focused on the strategies for the treatment of postmenopausal osteoporosis taking into consideration all the drugs available for this purpose. A short revision of the literature about treatment of secondary osteoporosis due both to androgen deprivation therapy for prostate cancer and to aromatase inhibitors for breast cancer was also performed. Also premenopausal females and males with osteoporosis are frequently seen in endocrine settings. Finally particular attention was paid to the tailoring of treatment as well as to its duration.

p53-dependent and p53-independent anticancer activity of a new indole derivative in human osteosarcoma cells

Osteosarcoma (OS) is the most common primary malignant tumor of bone, occurring most frequently in children and adolescents. The mechanism of formation and development of OS have been studied for a long time. Tumor suppressor pathway governed by p53 gene are known to be involved in the pathogenesis of osteosarcoma. Moreover, loss of wild-type p53 activity is thought to be a major predictor of failure to respond to chemotherapy in various human cancers. In previous studies, we described the activity of a new indole derivative, NSC743420, belonging to the tubulin inhibitors family, capable to induce apoptosis and arrest of the cell cycle in the G2/M phase of various cancer cell lines. However, this molecule has never been tested on OS cell line. Here we address the activity of NSC743420 by examine whether differences in the p53 status could influence its effects on cell proliferation and death of OS cells. In particular, we compared the effect of the tested molecule on p53-wild type and p53-silenced U2OS cells, and on SaOS2 cell line, which is null for p53. Our results demonstrated that NSC743420 reduces OS cell proliferation by p53-dependent and p53-independent mechanisms. In particular, the molecule induces proliferative arrest that culminate to apoptosis in SaOS2 p53-null cells, while it brings a cytostatic and differentiating effect in U2OS cells, characterized by the cell cycle arrest in G0/G1 phase and increased alkaline phosphatase activity.

Italian Association of Clinical Endocrinologists (AME) & Italian Association of Clinical Diabetologists (AMD) Position Statement : Diabetes mellitus and thyroid disorders: recommendations for clinical practice

Thyroid disease and diabetes mellitus, the most common disorders in endocrine practice, are not infrequently associated in the same subject. An altered thyroid function may affect glucose tolerance and worsen metabolic control in patients with diabetes. Thyrotoxicosis increases the risk of hyperglycemic emergencies, while a clinically relevant hypothyroidism may have a detrimental effect on glycemic control in diabetic patients. The association of alterations in thyroid function with diabetes mellitus may adversely affect the risk of cardiovascular and microvascular complications resulting from diabetes. Moreover, the treatments used for both diabetes and thyroid disease, respectively, can impact one other. Finally, multinodular goiter, but not thyroid carcinoma, was shown to be more prevalent in type 2 diabetes mellitus. Aim of the present Position Statement is to focus on the evidence concerning the association of thyroid disease and diabetes mellitus and to provide some practical suggestions for an updated clinical management.

Lateral neck recurrence from papillary thyroid carcinoma: Predictive factors and prognostic significance

OBJECTIVES/HYPOTHESIS

The aim of this study was to identify any possible predictive factors of lateral neck recurrence in patients with papillary thyroid carcinoma with no ultrasonographic and/or cytological evidence of lymph node metastasis at time of diagnosis. The influence of lateral neck recurrence on survival was also investigated.

STUDY DESIGN

Observational retrospective study.

METHODS

Retrospective review of clinical records of 610 patients surgically treated for papillary thyroid carcinoma with clinically negative lymph nodes at the Otolaryngology Unit of the Arcispedale Santa Maria Nuova-IRCCS, Reggio Emilia, Italy, from January 1984 to December 2008.

RESULTS

Lateral neck recurrences were ipsilateral to the primary tumor in all cases and were associated with the occurrence of more aggressive histological variants and central neck metastasis. Lateral neck recurrences were more frequently observed in patients with distant metastases and were associated with a reduced disease-specific survival.

CONCLUSION

Lateral neck compartment ipsilateral to the tumor was the most common site of recurrence, with about half of cases appearing in the first 28 months of follow-up. In patients with papillary thyroid carcinoma, detection of lateral neck metastases prior to first surgery is crucial to surgical planning. Aggressive histological variants and postsurgical evidence of lymph node metastasis from papillary thyroid carcinoma in central neck compartment are associated with a higher risk of lateral neck recurrence. In these patients, a closer postsurgical ultrasound surveillance of the lateral neck compartments seems worthwhile.

LEVEL OF EVIDENCE

4.

Increased prevalence of the GCM2 polymorphism, Y282D, in primary hyperparathyroidism: analysis of three Italian cohorts

CONTEXT

Glial cells missing-2 (GCM2) is key for parathyroid gland organogenesis. Its persistent expression in the adult parathyroid raises the possibility that overactive forms play a role in the evolution of parathyroid hyperactivity or tumorigenesis. A GCM2 c.844T → G; p.Y282D missense variant has been described within a transactivation inhibitory domain (amino acids 263-352).

OBJECTIVE

The aims of the study were to 1) assess the frequency of Y282D in Italian primary hyperparathyroidism (PHPT) and control (C) populations, 2) test for association of 282D with PHPT and its phenotypic features, and 3) compare the transactivation potency of GCM2 282D relative to wild-type Y282.

SUBJECTS AND METHODS

Subjects included a large southern Italian cohort (310 PHPT and 433 C) and 2 replication cohorts from northern Italy. Association of 282D with PHPT was tested in all cohorts and with phenotypic features in the larger PHPT cohort. An in vitro GCM promoter-luciferase reporter assay was conducted in HEK293 cells.

RESULTS

282D was significantly increased in the PHPT group, with a minor allele frequency of 0.066 compared with 0.029 in the C group (P = .0008), in the discovery cohort and was more prevalent in the replication cohorts. Combined analysis (510 PHPT and 665 C) yielded a likelihood ratio of 2.27 (95% confidence interval = 1.50-3.42; P < .0001). The 282D variant was not associated with serum calcium, phosphate, creatinine, or PTH levels or with bone mineral density, fractures, or renal stones in the PHPT group. The 282D variant had significantly greater transcriptional activity than the wild-type Y282 (17× basal vs 12× basal; P < 0.05).

CONCLUSION

The higher frequency of GCM2 282D in PHPT and enhanced transcriptional activity of this variant supports the notion that it could contribute causally to parathyroid tumorigenesis.

Using pathology-specific laboratory profiles in clinical pathology to reduce inappropriate test requesting: two completed audit cycles

Background

Systematic reviews have shown that, although well prepared, the Consensus Guidelines have failed to change clinical practice. In the healthcare district of Castelnovo né Monti (Reggio Emilia, Italy), it became necessary for the GPs and Clinical Pathologists to work together to jointly define laboratory profiles.

Methods

Observational study with two cycles of retrospective audit on test request forms, in a primary care setting. Objectives of the study were to develop pathology-specific laboratory profiles and to increase the number of provisional diagnoses on laboratory test request forms. A Multiprofessional Multidisciplinary Inter-hospital Work Team developed pathology-specific laboratory profiles for more effective test requesting. After 8 training sessions that used a combined strategy with multifaceted interventions, the 23 General Practitioners (GPs) in the trial district (Castelnovo nè Monti) tested the profiles; the 21 GPs in the Puianello district were the control group; all GPs in both districts participated in the trial. All laboratory tests for both healthcare districts are performed at the Laboratory located in the trial district. A baseline and a 1-year audit were performed in both districts on the GPs’ request forms.

Results

Seven pathology-specific laboratory profiles for outpatients were developed. In the year after the first audit cycle: 1) the number of tests requested in the trial district was distinctly lower than that in the previous year, with a decrease of about 5% (p < 0.001); 2) the provisional diagnosis on the request forms was 52.8% in the trial district and 42% in the control district (P < 0.001); 3) the decrease of the number of tests on each request form was much more marked in the trial district (8.73 vs. 10.77; p < 0.001).

Conclusions

The first audit cycle showed a significant decrease in the number of tests ordered only in the trial district. The combined strategy used in this study improved the prescriptive compliance of most of the GPs involved. The presence of the clinical pathologist is seen as an added value.

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.

Heterogeneity among methicillin-resistant Staphylococcus aureus from Italian pig finishing holdings

A survey for methicillin-resistant Staphylococcus aureus (MRSA) in finishing pig holdings was carried out in Italy in 2008. MRSA isolates were characterised by spa-, MLST-, SCCmec- and antimicrobial susceptibility typing. A prevalence of 38% (45/118, 95% CI 29.4-46.9%) positive holdings was observed. Eleven different spa-types were found among 102 MRSA isolates, clustering in lineages associated with farm animals (ST398, ST9, ST(CC)97 in 36 holdings) and humans (ST1, 7 holdings). Nine (7.6%) holdings were positive for two, three or four different and unrelated spa-types in various combinations. ST398 was the most prevalent lineage (33 positive holdings). The most prevalent spa-type was t899 (ST398), detected in 22 positive holdings. Three novel spa-types (t4794 of ST9; t4795 of ST97; t4838 of ST398) were detected. Ten holdings were positive for spa-type t1730, that proved to be a new single-locus variant of ST97, within the CC97 (ST1476). The most prevalent SCCmec was Type V (79 isolates), while Type IVb was found in 10 isolates. None of the isolates was positive for Panton-Valentine Leukocidin, while most of the t127 and t1730 isolates, one t4794, one t4795, and one t2922 were positive for LukE-LukD genes. All 64 antimicrobial susceptibility tested isolates were resistant to tetracyclines, with high resistance rates to trimethoprim (68.8%), erythromycin (60.9%), and ciprofloxacin (35.4%). All t127, ST1 isolates were resistant to tetracycline-ciprofloxacin-erythromycin. This survey provides the first report of MRSA ST1 and ST(CC)97 among pigs and the first report of MRSA ST9 from pigs in Europe. The presence of human-associated CA-MRSA (t127, ST1, SCCmec type V) in 6% holdings surveyed can represent an additional MRSA reservoir for infections in humans.

Evaluation of LRRK2 G2019S penetrance: relevance for genetic counseling in Parkinson disease

We report the results of a family-based study of LRRK2 G2019S penetrance in Parkinson disease. We studied 19 families identified through the analysis of unrelated consecutive patients. The cumulative incidence of the disease was 15% at 60 years, 21% at 70 years, and 32% at 80 years. This study provides accurate estimates of G2019S penetrance by minimizing the selection bias.

The G6055A (G2019S) mutation in LRRK2 is frequent in both early and late onset Parkinson's disease and originates from a common ancestor

BACKGROUND

Mutations in the gene Leucine-Rich Repeat Kinase 2 (LRRK2) were recently identified as the cause of PARK8 linked autosomal dominant Parkinson's disease.

OBJECTIVE

To study recurrent LRRK2 mutations in a large sample of patients from Italy, including early (<50 years) and late onset familial and sporadic Parkinson's disease.

RESULTS

Among 629 probands, 13 (2.1%) were heterozygous carriers of the G2019S mutation. The mutation frequency was higher among familial (5.1%, 9/177) than among sporadic probands (0.9%, 4/452) (p<0.002), and highest among probands with one affected parent (8.7%, 6/69) (p<0.001). There was no difference in the frequency of the G2019S mutation in probands with early v late onset disease. Among 600 probands, one heterozygous R1441C but no R1441G or Y1699C mutations were detected. None of the four mutations was found in Italian controls. Haplotype analysis in families from five countries suggested that the G2019S mutation originated from a single ancient founder. The G2019S mutation was associated with the classical Parkinson's disease phenotype and a broad range of onset age (34 to 73 years).

CONCLUSIONS

G2019S is the most common genetic determinant of Parkinson's disease identified so far. It is especially frequent among cases with familial Parkinson's disease of both early and late onset, but less common among sporadic cases. These findings have important implications for diagnosis and genetic counselling in Parkinson's disease.

American Association of Clinical Endocrinologists and Associazione Medici Endocrinologi medical guidelines for clinical practice for the diagnosis and management of thyroid nodules

Thyroid nodules are common and are frequently benign. Current data suggest that the prevalence of palpable thyroid nodules is 3% to 7% in North America; the prevalence is as high as 50% based on ultrasonography (US) or autopsy data. The introduction of sensitive thyrotropin (thyroid-stimulating hormone or TSH) assays, the widespread application of fine-needle aspiration (FNA) biopsy, and the availability of high-resolution US have substantially improved the management of thyroid nodules. This document was prepared as a collaborative effort between the American Association of Clinical Endocrinologists (AACE) and the Associazione Medici Endocrinologi (AME). Most Task Force members are members of AACE. We have used the AACE protocol for clinical practice guidelines, with rating of available evidence, linking the guidelines to the strength of recommendations. Key observations include the following. Although most patients with thyroid nodules are asymptomatic, occasionally patients complain of dysphagia, dysphonia, pressure, pain, or symptoms of hyperthyroidism or hypothyroidism. Absence of symptoms does not rule out a malignant lesion; thus, it is important to review risk factors for malignant disease. Thyroid US should not be performed as a screening test. All patients with a palpable thyroid nodule, however, should undergo US examination. US-guided FNA (US-FNA) is recommended for nodules > or = 10 mm; US-FNA is suggested for nodules < 10 mm only if clinical information or US features are suspicious. Thyroid FNA is reliable and safe, and smears should be interpreted by an experienced pathologist. Patients with benign thyroid nodules should undergo follow-up, and malignant or suspicious nodules should be treated surgically. A radioisotope scan of the thyroid is useful if the TSH level is low or suppressed. Measurement of serum TSH is the best initial laboratory test of thyroid function and should be followed by measurement of free thyroxine if the TSH value is low and of thyroid peroxidase antibody if the TSH value is high. Percutaneous ethanol injection is useful in the treatment of cystic thyroid lesions; large,symptomatic goiters may be treated surgically or with radioiodine. Routine measurement of serum calcitonin is not recommended. Suggestions for thyroid nodule management during pregnancy are presented. We believe that these guidelines will be useful to clinical endocrinologists, endocrine surgeons, pediatricians, and internists whose practices include management of patients with thyroid disorders. These guidelines are thorough and practical, and they offer reasoned and balanced recommendations based on the best available evidence.

Active circulation of bluetongue vaccine virus serotype-2 among unvaccinated cattle in central Italy

Several seroconversions occurring in 2002 among sentinel cattle during the bluetongue-vaccination campaign in Lazio and Tuscany (central Italy) led to the suspicion of vaccine-virus circulation. Therefore in 2003, 17 seroconverting sentinel herds were investigated for the characteristics of the virus involved. From these farms, 91 unvaccinated animals and 57 Culicoides pools were tested for the presence of the bluetongue vaccine virus (serotype-2) or other strains. The presence of vaccine virus serotype-2 was confirmed by PCR followed by restriction analysis in the whole blood of 17 unvaccinated sentinel cattle and 12 pools of Culicoides imicola or C. obsoletus. Of the 17 herds, five were positive only for vaccine virus serotype-2, four were positive for other strains and two for both the vaccine and other strains; the remaining premises were virologicaly negative. The vaccine virus serotype-2 also was detected in areas not included in the vaccination campaign.

Lymphangioleiomyomatosis associated with pulmonary metastasis from an occult papillary carcinoma of the thyroid: report of a case occurring in a patient without tuberous sclerosis

We report on 50-year-old woman without tuberous sclerosis, presenting with recurrent spontaneous pneumothorax. A CT-scan of the chest showed multiple, bilateral, thin-walled cysts, consistent with pulmonary lymphangioleiomyomatosis. A videothoracoscopic lung biopsy confirmed the diagnosis of lymphangioleiomyomatosis, but revealed also a micrometastasis from an occult papillary carcinoma of the thyroid gland. The main histologic differential diagnosis and the possible correlation between lymphangioleiomyomatosis and thyroid diseases are briefly discussed.

Frequent RET rearrangements in thyroid papillary microcarcinoma detected by interphase fluorescence in situ hybridization

Papillary thyroid microcarcinomas (measuring 1 cm or less in diameter) are very common thyroid tumors, which are present in 10% to 35% of post-mortem histopathological examinations of individuals whose death was due to a cause other than thyroid cancer. The molecular basis of this tumor is still poorly understood. Somatic mutations are better characterized in clinically evident papillary thyroid carcinomas (PTCs), the most common involving the proto-oncogene RET, which maps to 10q11.2. Molecular alterations of RET always lead to intra- or interchromosomal rearrangements. In this study we have investigated the status of RET in 21 microcarcinomas, by means of interphase fluorescence in situ hybridization (FISH). RET was rearranged in 52% of microcarcinomas, a statistically significant higher frequency than that found previously in clinically evident PTCs using the same technique. Moreover, interphase FISH allowed us to detect a putative novel type of rearrangement in a microcarcinoma, and we observed trisomies of chromosome 10 and other chromosomes in two adenomas surrounding two of the microcarcinomas. The strikingly high frequency of RET rearrangements in microcarcinomas strongly suggests that RET plays a role in the initiation of thyroid tumorigenesis but does not seem to be necessary for the further progression of the tumor.

RET rearrangements in familial papillary thyroid carcinomas

Familial papillary thyroid carcinoma (FPTC) is an inherited tumor characterized by a more aggressive phenotype than that of its sporadic counterpart. Its mode of inheritance as well as its genetic and molecular bases are still poorly understood. On the contrary, genetic alterations in sporadic papillary thyroid carcinoma (PTC) are better characterized, the most common one involving the activation of the proto-oncogene RET through somatic rearrangements. In the present study, we investigated by interphase fluorescence in situ hybridization the presence of RET rearrangements in a series of 20 FPTC. We show that one FPTC and the adenoma from the same patient carry a RET rearrangement (type PTC1) and that this rearrangement is absent in the germline. Furthermore, we excluded a RET haplotype sharing in two brothers of the same family. These results show that RET rearrangements can indeed be found in FPTC and confirm that RET is not involved in the inherited predisposition to FPTC.

Localization of a susceptibility gene for familial nonmedullary thyroid carcinoma to chromosome 2q21

The familial form of nonmedullary thyroid carcinoma (NMTC) is a complex genetic disorder characterized by multifocal neoplasia and a higher degree of aggressiveness than its sporadic counterpart. In a large Tasmanian pedigree (Tas1) with recurrence of papillary thyroid carcinoma (PTC), the most common form of NMTC, an extensive genomewide scan revealed a common haplotype on chromosome 2q21 in seven of the eight patients with PTC. To verify the significance of the 2q21 locus, we performed linkage analysis in an independent sample set of 80 pedigrees, yielding a multipoint heterogeneity LOD score (HLOD) of 3.07 (alpha=0.42), nonparametric linkage (NPL) 3.19, (P=.001) at marker D2S2271. Stratification based on the presence of at least one case of the follicular variant of PTC, the phenotype observed in the Tas1 family, identified 17 such pedigrees, yielding a maximal HLOD score of 4.17 (alpha=0.80) and NPL=4.99 (P=.00002) at markers AFMa272zg9 and D2S2271, respectively. These results indicate the existence of a susceptibility locus for familial NMTC on chromosome 2q21.

Exploration of cyclical changes in memory and mood in postmenopausal women taking sequential combined oestrogen and progestogen preparations

OBJECTIVE

To investigate the effect of progesterone on cognitive function, mood, sleep quality and libido when added to oestrogen in sequential combined hormonal replacement therapy regimens.

DESIGN

Observational study over three hormonal replacement therapy cycles.

SETTING

Menopause Centre of Ospedale Maternità, Bologna, Italy.

POPULATION

Twenty-three postmenopausal women with an average of 70 months of amenorrhoea (range 12 to 234 months) on different sequential combined hormonal replacement therapy regimen for an average of 15 months (range 3-48) months.

METHODS

Psychological testing for memory, mood, sleep quality and libido during the oestrogen only part of the cycle compared with the oestrogen-progestogen part of the cycle.

RESULTS

Twenty women completed the six visits of the trial. The addition of progestogens to oestrogen appeared to benefit memory (P < 0.01) but worsened mood (P < 0.005). There was no evidence of change in other parameters such as sleep quality or libido.

CONCLUSION

The addition of progestogens improved memory above what was obtained with oestrogen alone. This effect did not depend on an improvement of mood since the latter worsened during the progestogenic phase of an hormonal replacement therapy cycle. Progestogen added to oestrogen did not significantly influence sleep or libido.

Polyamines directly induce release of cytochrome c from heart mitochondria

Cytochrome c release from mitochondria to the cytosol represents a critical step in apoptosis, correlated to the activation of the caspase cascade. In this report, we show that addition of micromolar concentrations of polyamines to isolated rat heart mitochondria induces the release of cytochrome c. Spermine, which is effective at concentrations of 10-100 microM, is more potent than spermidine, whereas putrescine has no effect up to 1 mM. The release of cytochrome c caused by spermine is a rapid, saturable and selective process that is independent of mitochondria damage. Spermine, unlike polylysine, is able to release a discrete amount of cytochrome c from intact, functional mitochondria. The cytochrome c-releasing power of spermine is not affected by cyclosporin A, differently from the effect of permeability transition inducers. In a cardiac cell-free model of apoptosis, the latent caspase activity of cytosolic extracts from cardiomyocytes could be activated by cytochrome c released from spermine-treated heart mitochondria. These data indicate a novel mechanism of cytochrome c release from the mitochondrion, and suggest that prolonged and sustained elevation of polyamines, characteristic of some pathologies such as heart hypertrophy, could be involved in the development of apoptosis.

Association of elevated insulin-like growth factor binding protein-1 with insulin resistance in hyperthyroidism

OBJECTIVE

Insulin-like growth factor binding-protein-1 (IGFBP-1) has a role in glucose homeostasis and is present at high concentrations in hyperthyroidism. We have investigated the relationship between IGFBP-1 concentration and glucose homeostasis in hyperthyroidism.

DESIGN

Patients and controls had intravenous glucose tolerance tests (IVGTT) and/or oral glucose tolerance tests (OGTT). Patients were tested when hyperthyroid and when euthyroid whilst the controls were tested once. The IVGTT was used to assess insulin sensitivity and the OGTT to establish that the study group had abnormal glucose tolerance. The hyperthyroid patients were treated with methimazole to restore euthyroidism.

PATIENTS

Ten patients (9 females) and 13 healthy controls (9 females) consented to the study. Ten patients and nine controls (7 females) had IVGTT. Six patients (5 females) and six controls (4 females) had OGTT.

MEASUREMENTS

Glucose, insulin, glucagon, GH and IGFBP-1 were measured during GTT. IGF-I, free thyroid hormones, and TSH concentrations were measured basally.

RESULTS

Hyperthyroid subjects were insulin resistant and 67% had impaired glucose tolerance. Fasting IGFBP-1 levels were doubled in hyperthyroid subjects compared to healthy controls and correlated positively with free T4 (r = 0.84, P < 0.0001), with peak glucose during the OGTT (r = 0.68, P < 0.005) with peak insulin during the IVGTT (r = 0.51, P < 0.005) and negatively with glucose disappearance constant (r = - 0.52, P < 0.005). IGFBP-1 was highly phosphorylated in hyperthyroid and control subjects. Fasting insulin and IGFBP-1 levels were unrelated but IGFBP-1 suppressed acutely during GTT in all groups. GH levels fell less in patients with hyperthyroidism than in normals during GTTs.

CONCLUSIONS

We conclude that in hyperthyroidism thyroid hormones directly increase fasting IGFBP-1 concentration but acute regulation of IGFBP-1 by insulin is normal and that elevated fasting phosphorylated IGFBP-1 concentration is associated with insulin resistance.

Detection and diagnosis of parathyroid incidentalomas during thyroid sonography

PURPOSE

The aim of our study was to evaluate the incidence of incidentally found parathyroid adenomas (incidentalomas) in patients undergoing sonography of the neck for thyroid disease.

METHODS

A total of 1,686 patients (305 men and 1,381 women) underwent sonography of the neck; the mean age was 49.6 +/- 21.7 years. In 38 patients (2.3%; 7 men and 31 women) with a mean age of 48.7 +/- 14.7 years, hypoechoic, homogeneous, oval nodules (mean volume, 1.0 +/- 0. 9 cm(3)) adjacent to the thyroid parenchyma were observed. All these lesions, compatible with the shape of an enlarged parathyroid gland, underwent ultrasound-guided fine-needle aspiration biopsy (FNAB), with measurement of parathyroid hormone (PTH) and thyroglobulin (Tg) levels in the needle washings (FNAB-PTH and FNAB-Tg). Biochemical screening for hyperparathyroidism was also performed.

RESULTS

Cytologic examination plus FNAB-PTH/FNAB-Tg measurements revealed the presence of cellular material consistent with parathyroid tissue in 9 patients (24%), thyroid tissue in 22 patients (58%), and lymphoid tissue in 4 patients (11%). A tissue diagnosis was not established in 3 patients (8%). Five of 9 patients with parathyroid enlargement had high serum PTH and calcium levels.

CONCLUSIONS

Enlarged parathyroid glands may be incidentally discovered during sonography of the thyroid. In patients with thyroid disease, the positive-predictive value of sonography in the identification of parathyroid tissue was low. Ultrasound-guided FNAB-PTH determination should be carried out when parathyroid adenoma is suspected. The incidental finding of an enlarged parathyroid may or may not be associated with yet undiagnosed hyperparathyroidism.

[Epidemiologic investigation on the prevalence of goiter and urinary excretion of iodine in the school population of the province of Reggio Emilia]

The prevalence of goiter was evaluated in a sample from the schoolchildren population of Reggio Emilia district. 1020 children underwent physical examination of thyroid gland and thyroid ultrasonography for determination of thyroid volume. Urinary iodine excretion (UIE) was measured in 837/1020 (82.1%). Iodine content was measured in water samples collected from 65 wells and 12 springs all around the district. The prevalence of goiter according to thyroid gland palpation was 26.2%. Thyroid volume was 4.74 +/- 1.87 ml, and the median UIE value 85 micrograms/l. According to the UIE classes as defined by WHO, 57.8% of all subjects showed a UIE less than 100 micrograms/l. In 57 out of 65 wells and in all the 12 springs examined, iodine was completely absent. In the remaining 8 wells, only iodine traces were found. Based on the results of physical examination of the thyroid gland, Reggio Emilia district should be regarded as an endemic goiter area. Nevertheless, thyroid volume measurement by ultrasound indicates that goiter prevalence may be markedly overestimated by palpation. The high prevalence of subjects featuring an increased thyroid volume, the low median UIE value and the poor iodine content in the local reservoirs of drinkable water suggest the opportunity for iodine prophylaxis in the Reggio Emilia district.

Role of thyroglobulin measurement in fine-needle aspiration biopsies of cervical lymph nodes in patients with differentiated thyroid cancer

The identification of metastatic neck lymph nodes in patients awaiting surgery for differentiated thyroid tumor permits their excision during thyroidectomy. In order to detect thyroid cancer lymphatic metastasis before surgery, we measured thyroglobulin (Tg) in the needle wash-out of fine-needle aspiration biopsy (FNAB). Ultrasound-guided FNAB on enlarged neck nodes was performed in 23 patients awaiting surgery for differentiated thyroid tumor (n = 33 lymph nodes), 47 patients previously thyroidectomized for thyroid tumor (n = 89 lymph nodes), and 60 patients without thyroid disease (n = 94 lymph nodes). Immediately after aspiration biopsy, the needle was rinsed with 1 mL of normal saline solution and Tg levels were measured on the needle wash-out (FNAB-Tg). FNAB-Tg levels were markedly elevated in metastatic lymph nodes both in patients awaiting thyroidectomy (metastatic vs. negative lymph nodes, mean +/- SEM, 16,593 +/- 7,050 ng/mL vs. 4.91 +/- 1.61 ng/mL; p < 0.001) and in thyroidectomized patients (11,541 +/- 7,283 ng/mL vs. 0.45 +/- 0.07 ng/mL; p < 0.001). FNAB-Tg sensitivity, evaluated through histological examination in 69 lymph nodes, was 84.0%. The combination of cytology plus FNAB-Tg increased FNAB sensitivity from 76% to 92.0%. In conclusion, FNAB-Tg measurement is a useful technique for early diagnosis of lymph node metastasis originating from differentiated thyroid cancer.

In obesity, glucose load loses its early inhibitory, but maintains its late stimulatory, effect on somatotrope secretion

Glucose load has a biphasic effect on GH secretion. In fact, in normal subjects, glucose load has a prompt inhibitory and a late stimulatory effect on both spontaneous and GHRH-induced GH levels. The mechanism underlying the inhibitory effect is probably mediated by the increase in hypothalamic somatostatin, whereas that underlying the stimulatory effect is unclear. On the other hand, in obesity, a reduced somatotrope responsiveness to all GH secretagogues is well known, whereas recently, we found that glucose load, but not pirenzepine and somatostatin, fails to inhibit the GHRH-induced GH rise. Thus, the inhibitory effect of hyperglycemia on GH secretion is selectively lacking in obesity. The aim of the present study was to verify whether in obesity the late stimulatory effect of glucose on GH secretion is preserved. We studied 15 female obese patients (OB; age, 33.9 +/- 2.6 yr; body mass index, 36.4 +/- 1.5 kg/m2; waist/hip ratio, 0.9 +/- 0.1) and 12 normal female subjects (NS; 26.5 +/- 1.0 yr; 21.4 +/- 0.3 kg/m2) as controls. Two studies were performed. In study A (six OB and six NS) we evaluated the somatotrope response to GHRH (1 microgram/kg, i.v., at 0 min) alone or preceded by oral glucose (OGTT; 100 g, orally, at -45 min). In study B (nine OB and six NS) we studied the somatotrope response to OGTT (100 g, orally, at 0 min), saline plus GHRH (1 microgram/kg, iv, at 150 min), and OGTT plus GHRH. In study A, the GHRH-induced GH rise in NS was higher (P < 0.01) than that in OB. OGTT blunted the GHRH-induced GH rise in NS (0-90 min area under the curve, 318.9 +/- 39.1 vs. 696.3 +/- 110.8 micrograms/min-L; P < 0.05), but failed to modify it in OB (289.1 +/- 51.7 vs. 283.9 +/- 44.0 micrograms/min-L). In study B, the GHRH-induced GH rise in NS was higher (P < 0.01) than that in OB. OGTT induced a late GH increase in both NS (150-240 min area under the curve, 249.6 +/- 45.2 micrograms/min-L) and OB (103.2 +/- 31.4 micrograms/min-L). Moreover, OGTT enhanced the GHRH-induced GH rise in NS as well as in OB [1433.0 +/- 202.0 vs. 967.9 +/- 116.3 micrograms/min-L (P < 0.03) and 763.8 +/- 131.0 vs. 278.1 +/- 52.3 micrograms/min-L (P < 0.01), respectively]. The GH responses to OGTT alone and combined with GHRH in OB were lower (P < 0.03) than those in NS. Our data show that in human obesity, the oral glucose load loses its precocious inhibitory effect on the GHRH-induced GH rise but maintains its late stimulatory effect on somatotrope secretion. These findings suggest that the inhibitory and stimulatory effects of glucose load on GH secretion are unlikely to be due to biphasic modulation of hypothalamic somatostatin release, which seems selectively refractory to stimulation by hyperglycemia in obesity.

Influence of thyroid status on serum immunoreactive leptin levels

Leptin, the product of the ob gene, is a recently discovered hormone secreted by adipocytes. Serum leptin concentrations increase in correlation with the percentage of body fat, but besides that, little is known about the physiological actions of leptin in humans. The aim of this study was to assess the influence of hypo- and hyperthyroidism on serum leptin levels. Thirty-two patients (16 with hypothyroidism and 16 with hyperthyroidism) were studied before and after treatment with replacement doses of T4 (hypothyroid patients) or methimazole (hyperthyroid), when thyroid function was normal. Control serum for each group was obtained from healthy age-, sex-, and body mass index-matched subjects. Plasma leptin levels were measured by specific RIA. The mean leptin level in the hypothyroid patients was lower before treatment (4.7 +/- 0.7 microg/L) than that in the controls (8.6 +/- 1.4 microg/L; P < 0.02) and was lower than that during treatment with T4 and normalization of thyroid function in the same group of patients (6.3 +/- 0.8 microg/L; P < 0.05). Leptin levels in the hyperthyroid patients were similar before (7.2 +.0 1.1 microg/L) and after normalization of thyroid function following treatment with methimazole (6.2 +/- 1.1 microg/L) and were similar to the control value (8.8 +/- 1.4 microg/L). In conclusion, leptin levels are decreased in the hypothyroid patients and unchanged in hyperthyroidism. Whether decreased leptin levels may contribute to the decreased energy expenditure in patients with hypothyroidism merits further investigation.

Effects of trimetazidine on the calcium transport and oxidative phosphorylation of isolated rat heart mitochondria

Trimetazidine (TMZ) added in vitro to isolated cardiac mitochondria at concentrations 10-100 microM in the presence of 25-100 nM extramitochondrial Ca2+ increased Ca2+ uptake and matrix Ca2+ concentration. This effect was less evident in the presence of physiologically Na+ and Mg2+ extramitochondrial concentrations since only 100 microM TMZ was able to increase mitochondrial Ca2+ entry in the presence of 100 nM Ca2+. The drug stimulated a Ca(2+)-cooperative effect on mitochondrial Ca2+ transport, but did not modify the rate of Ca2+ egress stimulated by 10 mM NaCl. An increase in mitochondrial Ca2+ level produced by TMZ enhanced oxoglutarate dehydrogenase activity and then ATP synthesis, particularly when 50 nM extramitochondrial Ca2+ was used. These data suggest that a possible cardiac mechanism of action of TMZ at mitochondrial level could support ATP synthesis by elevating the mitochondrial Ca2+ level.

Pulsatile gonadotrophin secretion in hypothyroid women of reproductive age

Hypothyroid women may have various disturbances of the reproductive system. Although menstrual cycle disturbances and infertility have been reported in hypothyroidism, gonadotrophin levels have usually been found in the normal range. We have investigated whether female hypothyroid patients of reproductive age have any alteration in the pulsatile secretory pattern of gonadotrophin secretion. LH and FSH were assayed on days 2-5 of the menstrual cycle in blood samples taken every 10 min for 8 h from six hypothyroid women and six age-matched control subjects. Pulsatility was analysed using the Cluster and Detect programs. There was no significant difference in the number of peaks identified (3.7 +/- 0.8 vs 3.7 +/- 0.8 for LH, and 3.7 +/- 0.8 vs 4.2 +/- 0.5 for ESH), the mean duration of peaks (LH: 68.0 +/- 6.9 vs 72.7 +/- 5.1 min; FSH: 81.9 +/- 8.1 vs 71.2 +/- 10.3 min), the area under the peaks (LH: 91.5 +/- 20.4 vs 148.2 +/- 55.1 IU/l per min; FSH: 71.5 +/- 4.5 vs 62.7 +/- 15.0 IU/l per min), and the incremental amplitude from baseline (LH: 2.2 +/- 0.4 vs 3.0 +/- 0.8 IU/l; FSH: 1.4 +/- 0.2 vs 2.1 +/- 0.5 IU/ l). However, the absolute pulse amplitude was greater in hypothyroid patients (LH: 14.5 +/- 1.4 vs 8.3 +/- 1.3 IU/l, P < 0.01; FSH: 9.0 +/- 1.5 vs 5.8 +/- 1.2 IU/l, P = 0.04), as were the integrated concentrations (LH: 6.6 +/- 0.7 vs 3.2 +/- 0.4 IU/l per min, P < 0.01; FSH: 4.3 +/- 0.4 vs 2.1 +/- 0.5 IU/l per min, P < 0.01). Oestradiol values were comparable in the two groups (42.7 +/- 0.4 vs 43.5 +/- 9.7 pg/ml). These results indicate that in hypothyroid women there is an increased baseline level with a normal pulsatility of the gonadotrophin secretion. Similar oestrogen levels in both groups, and normal or near-normal cycles in our patients suggest either a decreased biological potency of the gonadotrophins or a mild ovarian resistance.

Localization of the dystrophin binding site at the carboxyl terminus of beta-dystroglycan

Alpha- and beta-dystroglycan form a heteromeric transmembrane complex linking the extracellular matrix to the cytoskeleton. In muscle beta-dystroglycan interacts with dystrophin on the inside of the cell and with alpha-dystroglycan, which binds the extracellular matrix protein laminin, on the outside. Dystroglycan is expressed not only in muscle but also in other tissues. We cloned beta-dystroglycan from rabbit brain by RT-PCR and expressed deletion mutants of the beta-dystroglycan cytoplasmic domain as GST-fusion proteins. We identified the dystrophin binding region on beta-dystroglycan by protein overlay and co-precipitation assays with skeletal muscle dystrophin and recombinant apo-dystrophin I. We demonstrate that the beta-dystroglycan carboxyl terminus interacts with dystrophin and that the binding site is restricted to the last 20 amino acids. Our data also suggest that the region adjacent to the beta-dystroglycan transmembrane domain might modulate beta-dystroglycan-dystrophin interaction.