The onset time of amiodarone-induced thyrotoxicosis (AIT) depends on AIT type

Objective: Considering the different pathogenic mechanisms of the two main forms of amiodarone-induced thyrotoxicosis (AIT), we ascertained whether this results in a different onset time as well. Design and methods: We retrospectively analyzed the clinical records of 200 consecutive AIT patients (157 men and 43 women; mean age 62.2G12.6 years) referred to our Department from 1987 to 2012. The onset time of AIT was defined as the time elapsed from the beginning of amiodarone therapy and the first diagnosis of thyrotoxicosis, expressed in months. Factors associated with the onset time of AIT were evaluated by univariate and multivariate analyses. Results: The median onset time of thyrotoxicosis was 3.5 months (95% CI 2–6 months) in patients with type 1 AIT (AIT1) and 30 months (95% CI 27–32 months, P!0.001) in those with type 2 AIT (AIT2). Of the total number of patients, 5% with AIT1 and 23% with AIT2 (PZ0.007) developed thyrotoxicosis after amiodarone withdrawal. Factors affecting the onset time of thyrotoxicosis were the type of AIT and thyroid volume (TV). Conclusions:ThedifferentpathogenicmechanismsofthetwoformsofAITaccountfordifferentonsettimesofthyrotoxicosisin the two groups. Patients with preexisting thyroid abnormalities (candidate to develop AIT1) may require a stricter follow-up during amiodarone therapy than those usually recommended. In AIT1, the onset of thyrotoxicosis after amiodarone withdrawal is rare, while AIT2 patients may require periodic tests for thyroid function longer after withdrawing amiodarone

Continuation of amiodarone delays restoration of euthyroidism in patients with type 2 amiodarone-induced thyrotoxicosis treated with prednisone: a pilot study

Context: Type 2 amiodarone-induced thyrotoxicosis (AIT) is a destructive thyroiditis usually re- sponsive to glucocorticoids. Whether continuation of amiodarone affects treatment outcome is unsettled. Objective: The objective of the study was to compare the outcome of glucocorticoid treatment in type 2 AIT patients who continued or withdrew amiodarone. Design: This was a matched retrospective cohort study. Setting: The study was conducted at a university center. Patients: Eighty-three consecutive patients with untreated type 2 AIT participated in the study. After matching with patients continuing amiodarone (AMIO-ON, n 8), patients interrupting amiodarone were randomly selected in a 4:1 ratio (AMIO-OFF, n 32). Intervention: All patients were treated with oral prednisone. Patients whose thyrotoxicosis re- curred after glucocorticoid withdrawal were treated with a second course of prednisone. Main Outcome Measure: Time and rate of cure were measured. Results: Median time to the first normalization of serum thyroid hormone levels did not signifi- cantly differ in AMIO-ON and AMIO-OFF patients (24 and 31 d, respectively; P 0.326). Conversely, median time for stably restoring euthyroidism was 140 d in AMIO-ON patients and 47 d in AMIO- OFF patients (log rank, P 0.011). In fact, AIT recurred in five of seven AMIO-ON patients (71.4%) and in only three of 32 AMIO-OFF patients (9.4%, P 0.002), requiring readministration of pred- nisone. One AMIO-ON patient never reached thyroid hormone normalization during the study period. Factors associated with glucocorticoid failure were thyroid volume and amiodarone continuation. Conclusions: Prednisone restores euthyroidism in most type 2 AIT patients, irrespective of amio- darone continuation or withdrawal. However, continuing amiodarone increases the recurrence rate of thyrotoxicosis, causing a delay in the stable restoration of euthyroidism and a longer exposure of the heart to thyroid hormone exces

2078 High prevalence of cardiac hypertophy without detectable signs of fibrosis in patients with untreated active acromegaly: an in-vivo study using magnetic resonance imaging and integrated backscatter analysis

Introduction Left ventricular (LV) hypertrophy and myocardial fibrosis are considered the main pathological features of acromegalic cardiomyopathy. Cardiovascolar Magnetic Resonance (CMR) allows to detect myocardial gross fibrosis using the delayed enhancement (DE) technique. Myocardial echointensity as derived by integrated backscatter (IBS) echocardiographic analysis is considered an index of myocardial collagen content

Growth Hormone Is Necessary for the p53-Mediated, Obesity-Induced Insulin Resistance in Male C57BL/6J × CBA Mice

Insulin resistance is a key marker of both obesity and GH excess. The purpose of the study was to assess the role of GH on p53-mediated insulin resistance of male mice with obesity due to a high-fat diet. C57BL/6J CBA male mice fed on a high-fat diet (Obe) were studied; male mice fed a normal diet (Lean) or transgenic mice for bovine GH under the same genetic background (Acro) served as controls. The convergence of p53 and GH pathways was evaluated by Western blot. Obe mice had insulin resistance, which was sustained by a selective increased expression of p53 in adipose tissue. Normal insulin sensitivity was restored, and adipose p53 expression normalized when the GH pathway was blocked. Only the adipose p53 expression was sensitive to the GH blockage, which occurred through the p38 pathway. Adipose tissue of Obe mice had a coordinate overexpres- sion of suppressors of cytokine signal 1–3 and signal transducers and activators of transcrip- tion-1, -3, and -5b, not different from that of Acro mice, suggesting an increased sensitivity of adipose tissue to GH. On the contrary, Lean mice were unaffected by changes of GH action. GH seems to be necessary for the increased adipose p53 expression and for insulin resistance of obese mice

A multimodal approach to the treatment of bilateral choroidal metastases from thyroid carcinoma

A 58-year old man, affected by metastatic thyroid carcinoma, experienced a progressive bilateral visual impairment. Ophthalmic examination revealed the presence of a choroidal mass with an associated exudative retinal detachment in both eyes. Twelve years before, a diagnosis of metastatic thyroid carcinoma had been established and the patient had been subject to several therapeutic procedures

Mutational and large deletion study of genes implicated in hereditary forms of primary hyperparathyroidism and correlation with clinical features

The aim of this study was to carry out genetic screening of the MEN1, CDKN1B and AIP genes, both by direct sequencing of the coding region and multiplex ligation-dependent probe amplification (MLPA) assay in the largest monocentric series of Italian patients with Multiple Endocrine Neoplasia type 1 syndrome (MEN1) and Familial Isolated Hyperparathyroidism (FIHP). The study also aimed to describe and compare the clinical features of MEN1 mutation-negative and mutation-positive patients during long-term follow-up and to correlate the specific types and locations of MEN1 gene mutations with onset and aggressiveness of the main MEN1 manifestations. A total of 69 index cases followed at the Endocrinology Unit in Pisa over a period of 19 years, including 54 MEN1 and 15 FIHP kindreds were enrolled. Seven index cases with MEN1 but MEN1 mutation-negative, followed at the University Hospital of Cagliari, were also investigated. FIHP were also tested for CDC73 and CaSR gene alterations. MEN1 germline mutations were identified in 90% of the index cases of familial MEN1 (F-MEN1) and in 23% of sporadic cases (S-MEN1). MEN1 and CDC73 mutations accounted for 13% and 7% of the FIHP cohort, respectively. A CDKN1B mutation was identified in one F-MEN1. Two AIP variants of unknown significance were detected in two MEN1-negative S-MEN1. A MEN1 positive test best predicted the onset of all three major MEN1-related manifestations or parathyroid and gastro-entero-pancreatic tumors during follow-up. A comparison between the clinical characteristics of F and S-MEN1 showed a higher prevalence of a single parathyroid disease and pituitary tumors in sporadic compared to familial MEN1 patients. No significant correlation was found between the type and location of MEN1 mutations and the clinical phenotype. Since all MEN1 mutation-positive sporadic patients had a phenotype resembling that of familial MEN1 (multiglandular parathyroid hyperplasia, a prevalence of gastro-entero-pancreatic tumors and/or the classic triad) we might hypothesize that a subset of the sporadic MEN1 mutation-negative patients could represent an incidental coexistence of sporadic primary hyperparathyroidism and pituitary tumors or a MEN1 phenocopy, in our cohort, as in most cases described in the literature

Comparison of the effects of primary somatostatin analogue therapy and pituitary adenomectomy on survival in patients with acromegaly: a retrospective cohort study

Objective: Acromegalic patients have an increased risk of mortality. The objective of this study was to compare the effect of different therapies for acromegaly on mortality. Design and methods: The mortality rate of 438 consecutive acromegalic patients was compared with that of the general population using the standardized mortality ratio (SMR); the effect of different therapies on survival was evaluated using Cox regression analysis. Results: Twenty patients (4.5%) died between 1999 and 2009. Age- and sex-adjusted SMR was 0.70 (95% CI 0.43–1.08). The Cox regression analysis revealed that, in the whole population, both general risk factors (age and physical status) and specific factors for acromegaly (macroadenoma, hypopituitarism and uncontrolled disease) were associated with death. The most compromised patients at diagnosis had a higher mortality rate (PZ0.001), which also occurred in patients with controlled acromegaly. Death occurred in 2.4% (adenomectomy), 2.6% (adenomectomy followed by somatostatin analogue (SSA) therapy) and 11.4% (SSA therapy as the primary therapy) of the patients. The risk of death was higher in patients receiving SSA therapy as the primary therapy (hazard ratio (HR) 5.52, 95% CI 1.06–28.77, PZ0.043) than in all patients submitted to adenomectomy; however, a higher risk of death occurred only in diabetic patients treated with SSAs alone (HR 21.94, 95% CI 1.56–309.04, PZ0.022). Radiotherapy was associated with an increased risk of mortality, which occurred in patients with the more locally advanced disease. Conclusions: Therapies for acromegaly and comorbidities have lowered the risk of mortality to the level of the general population; the effect of SSA therapy alone or that following pituitary adenomectomy was comparable to that of curative neurosurgery on survival in non-diabetic patients; on the contrary, SSA therapy as the primary therapy may be less effective than adenomectomy in reducing mortality rate in diabetic patients