Latin American Thyroid Society Research Articles

Use of thyroid hormones in hypothyroid and euthyroid patients: a 2022 THESIS questionnaire survey of members of the Latin American Thyroid Society (LATS)

PurposeInconsistencies in the medical management of hypothyroidism have been reported between endocrinologists in different countries. This study aimed to identify the attitudes of Latin America thyroid specialists towards the use of thyroid hormones.MethodsOnline survey of members of the Latin America Thyroid Society.Results81/446 (18.2%) completed the questionnaire. Levothyroxine (LT4) was the initial treatment of choice for all respondents. 56.8% would consider LT4 use in biochemically euthyroid patients: infertile women with elevated anti-thyroid antibodies (46.9%), resistant depression (17.3%) and growing goiter (12%). Most respondents preferred tablets (39.5%) over liquid formulations (21.0%) or soft gel capsules (22.2%) and would not consider switching formulations in patients with persistent symptoms. 39.5% would never use LT4 + liothyronine (LT3) combination therapy in symptomatic euthyroid patients, due to low quality evidence for benefit. 60.5% reported that persistence of symptoms despite normal TSH is rare (below 5% of patients) and its prevalence has been stable over the last five years. Psychosocial factors (84.0%), comorbidities (86.4%) and the patient unrealistic expectation (72.8%) were considered the top three explanations for this phenomenon.ConclusionLT4 tablets is the treatment of choice for hypothyroidism. A significant proportion of respondents would use LT4 in some groups of euthyroid individuals, contrasting the recommendations of the major clinical practice guideline indications. LT4 + LT3 combination treatment in euthyroid symptomatic patients was considered by nearly 50%. Practices based on weak or absent evidence included use of thyroid hormones for euthyroid subjects by 56.8% of respondents and use of LT4 + LT3 treatment by 60.5% of respondents for patients with persistent symptoms. In contrast to many European countries, LATS respondents report a low and unchanged proportion of dissatisfied patients over the last five years.

Management of radioiodine refractory differentiated thyroid cancer: the Latin American perspective.

Radioiodine (RAI) refractory differentiated thyroid cancer is an uncommon and challenging situation that requires a multidisciplinary approach to therapeutic strategies. The definition of RAI-refractoriness is usually a clear situation in specialized centers. However, the right moment for initiation of multikinase inhibitors (MKI), the time and availability for genomic testing, and the possibility of prescribing MKI and selective kinase inhibitors differ worldwide.Latin America (LA) refers to the territories of the world that stretch across two regions: North America (including Central America and the Caribbean) and South America, containing 8.5% of the world's population. In this manuscript, we critically review the current standard approach recommended for patients with RAI refractory differentiated thyroid cancer, emphasizing the challenges faced in LA. To achieve this objective, the Latin American Thyroid Society (LATS) convened a panel of experts from Brazil, Argentina, Chile, and Colombia. Access to MKI compounds continues to be a challenge in all LA countries. This is true not only for MKI but also for the new selective tyrosine kinase inhibitor, which will also require genomic testing, that is not widely available. Thus, as precision medicine advances, significant disparities will be made more evident, and despite efforts to improve coverage and reimbursement, molecular-based precision medicine remains inaccessible to most of the LA population. Efforts should be undertaken to alleviate the discrepancies between the current state-of-the-art care for RAI-refractory differentiated thyroid cancer and the present situation in Latin America.

Clinician Agreement on the Classification of Thyroid Nodules Ultrasound Features: A Survey of 2 Endocrine Societies.

Thyroid nodule risk stratification allows clinicians to standardize the evaluation of thyroid cancer risk according to ultrasound features. To evaluate interrater agreement among clinicians assessing thyroid nodules ultrasound features and thyroid cancer risk categories. We surveyed Endocrine Society and Latin American Thyroid Society members to assess their interpretation of composition, echogenicity, shape, margins, and presence of echogenic foci of 10 thyroid nodule cases. The risk category for thyroid cancer was calculated following the American College of Radiology-Thyroid Imaging Reporting & Data System (ACR-TIRADS) framework from individual responses. We used descriptive statistics and Gwet's agreement coefficient (AC1) to assess the primary outcome of interrater agreement for ACR-TIRADS risk category. As secondary outcomes, the interrater agreement for individual features and a subgroup analysis of interrater agreement for the ACR-TIRADS category were performed (ultrasound reporting system, type of practice, and number of monthly appraisals). A total of 144 participants were included, mostly endocrinologists. There was moderate level of agreement for the absence of echogenic foci (AC1 0.53, 95% CI 0.24-0.81) and composition (AC1 0.54, 95% CI 0.36-0.71). The agreement for margins (AC1 0.24, 95% CI 0.15-0.33), echogenicity (AC1 0.34, 95% CI 0.22-0.46), and shape assessment (AC1 0.42, 95% CI 0.13-0.70) was lower. The overall agreement for ACR-TIRADS assessment was AC1 0.29, (95% CI 0.13-0.45). The AC1 of ACR-TIRADS among subgroups was similar. This study found high variation of judgments about ACR-TIRADS risk category and individual features, which poses a potential challenge for the widescale implementation of thyroid nodule risk stratification.

Results of treatment of papillary thyroid microcarcinoma adapted to risk of recurrence.

The incidence of papillary thyroid microcarcinoma (PTMC) is increasing. To analyze the long-term prognosis of PTMC. Study population: patients with a histopathological diagnosis of PTMC (size ≤ 1 cm) treated according to the risk of recurrence of the Latin American Thyroid Society. Inclusion criteria: minimum follow-up of 2 years, availability of histopathological samples, and treatment compliance. Exclusion criteria: previous thyroid surgery, other synchronous malignancies or ectopic location of the PTMC. Study variables: persistences, recurrences and mortality. Based on the risk of recurrence, PTMC has very low risk in 65.2% (n = 105), low risk in 17.4% (n = 28) and high risk in 17.4% (n = 28). In high risk patients, total thyroidectomy was performed in all cases, cervical lymphadenectomy in 57,1% (n = 16) and metabolic therapy with I131 in all cases. During a mean follow-up of 119,8 ± 65 months, 0.6% (n = 1) of recurrences took place. Risk factors associated to recurrence were not identified. No patient died due to MCPT. PTMC treated based on its risk of recurrence has a good long-term prognosis, without persistences, with a low number of recurrences and absence of disease-associated mortality.

Case Finding for Hypothyroidism Should Include Type 2 Diabetes and Metabolic Syndrome Patients: A Latin American Thyroid Society (LATS) Position Statement

Latin American Thyroid Society (LATS) Hypothyroidism Clinical Practice Guidelines recommend case finding of hypothyroid patients in multiple and different situations that agree with other Society guidelines. However, the detection of hypothyroidism in type 2 diabetes mellitus (T2DM) or metabolic syndrome (MetS) patients is not mentioned in particular. In the recent years, several basic and epidemiologic studies have appeared showing that a lower thyroid function and MetS/T2DM are associated. Hence, the aim of this review is to manifest the LATS position on the diagnosis of hypothyroidism in both MetS and T2DM patients. A search was made in PubMed using the following terms: "hypothyroidism" AND "diabetes" OR "metabolic syndrome." The most relevant studies describing the prevalence and complications due to hypothyroidism in both MetS and T2DM patients were selected. The current document reviews new information from studies that have shown that the prevalence of hypothyroidism is higher in T2DM patients (odds ratio [OR], 3.45; 95% confidence interval [CI], 2.5 to 4.7) and that diabetic complications are more prevalent in subclinical hypothyroidism (ScH). The incidence of T2DM is 1.09-fold higher with each doubling of thyroid-stimulating hormone (TSH) mIU/L (95% CI, 1.06 to 1.12), and the incidence of prediabetes increases 15% (hazard ratio, 1.15; 95% CI, 1.04 to 1.26) in patients with TSH >5 mIU/L. Similarly, MetS is more prevalent in ScH compared to euthyroid individuals (OR, 1.31; 95% CI, 1.08 to 1.60). Thyroid function is affected in MetS and T2DM, and hypothyroidism is more common in these patients. Diabetic complications are more frequent in ScH patients. Therefore, LATS now recommends aggressive case finding of hypothyroidism in both MetS and T2DM patients. CI = confidence interval; GLUT4 = glucose transporter 4; HOMA-IR = homeostatic model assessment for insulin resistance; HR = hazard ratio; LATS = Latin American Thyroid Society; MetS = metabolic syndrome; OR = odds ratio; ScH = subclinical hypothyroidism; T2DM = type 2 diabetes mellitus; T3 = triiodothyronine; T4 = thyroxine; TSH = thyroid-stimulating hormone.

Management of gestational hypothyroidism: results of a Brazilian survey.

Evaluate the management of hypothyroidism in fertile-aged and pregnant women and compare these practices to the recommendations of the Brazilian Society of Endocrinology and Metabolism (SBEM) and the Latin American Thyroid Society, published in 2013. In the first trimester of 2014, SBEM made available to all members an electronic questionnaire based on clinical scenarios in the management of gestational hypothyroidism. The responses of 406 physicians, most of them endocrinologists, were analyzed. Eighty-one per cent of the endocrinologists screen all their pregnant patients for thyroid dysfunction, mostly during the pregestational period or after the first prenatal visit. Following screening, 82% of the respondents initiate treatment when TSH levels are > 2.5 mIU/L while 67% monitor their pregnant patients even if TSH was normal on first trimester screening. For hypothyroid women who are planning pregnancy, 96% of the clinicians are aware of the importance of adjusting the levothyroxine (LT4) dose as soon as pregnancy is confirmed. However, opinions diverge with respect to adjusting the LT4 dose before or after reassessing thyroid function. The most widely used tests for monitoring pregnant women in use of LT4 are TSH and free T4 (62%) or TSH alone (21%). Unanimously, the treatment goal is to achieve the target TSH level for each trimester of gestation. The recommendations of the consensus statements are incorporated into the respondents' clinical practice. It is noteworthy that the great majority of the clinicians favor universal screening.

Aggressive case finding: a clinical strategy for the documentation of thyroid dysfunction.

Ideas and Opinions18 August 2015Aggressive Case Finding: A Clinical Strategy for the Documentation of Thyroid DysfunctionJames V. Hennessey, MD, Irwin Klein, MD, Kenneth A. Woeber, MD, Rhoda Cobin, MD, and Jeffrey R. Garber, MDJames V. Hennessey, MDFrom Harvard Medical School, Beth Israel Deaconess Medical Center, and Harvard Vanguard Medical Associates, Boston, Massachusetts; New York University School of Medicine and Icahn School of Medicine at Mount Sinai, New York, New York; University of California, San Francisco Medical School, San Francisco, California; and American Association of Clinical Endocrinologists Thyroid Scientific Taskforce, Jacksonville, Florida.Search for more papers by this author, Irwin Klein, MDFrom Harvard Medical School, Beth Israel Deaconess Medical Center, and Harvard Vanguard Medical Associates, Boston, Massachusetts; New York University School of Medicine and Icahn School of Medicine at Mount Sinai, New York, New York; University of California, San Francisco Medical School, San Francisco, California; and American Association of Clinical Endocrinologists Thyroid Scientific Taskforce, Jacksonville, Florida.Search for more papers by this author, Kenneth A. Woeber, MDFrom Harvard Medical School, Beth Israel Deaconess Medical Center, and Harvard Vanguard Medical Associates, Boston, Massachusetts; New York University School of Medicine and Icahn School of Medicine at Mount Sinai, New York, New York; University of California, San Francisco Medical School, San Francisco, California; and American Association of Clinical Endocrinologists Thyroid Scientific Taskforce, Jacksonville, Florida.Search for more papers by this author, Rhoda Cobin, MDFrom Harvard Medical School, Beth Israel Deaconess Medical Center, and Harvard Vanguard Medical Associates, Boston, Massachusetts; New York University School of Medicine and Icahn School of Medicine at Mount Sinai, New York, New York; University of California, San Francisco Medical School, San Francisco, California; and American Association of Clinical Endocrinologists Thyroid Scientific Taskforce, Jacksonville, Florida.Search for more papers by this author, and Jeffrey R. Garber, MDFrom Harvard Medical School, Beth Israel Deaconess Medical Center, and Harvard Vanguard Medical Associates, Boston, Massachusetts; New York University School of Medicine and Icahn School of Medicine at Mount Sinai, New York, New York; University of California, San Francisco Medical School, San Francisco, California; and American Association of Clinical Endocrinologists Thyroid Scientific Taskforce, Jacksonville, Florida.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M15-0762 Annals Author Insight Video - James V. Hennessey, MD In this video, James V. Hennessey, MD, offers additional insight into his Ideas and Opinions piece, "Aggressive Case Finding: A Clinical Strategy for the Documentation of Thyroid Dysfunction." SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Thyroid dysfunction is common, is readily diagnosed, and is treated in a cost-effective manner. Recently, the U.S. Preventive Services Task Force did not recommend screening for thyroid dysfunction in nonpregnant adults because of a lack of evidence that screening of asymptomatic patients affects clinical outcomes (1, 2). In contrast, over the last decade, 7 professional organizations, including the American Association of Clinical Endocrinologists, American Thyroid Association, and Latin American Thyroid Society, have given guidance on how and when to use thyroid-stimulating hormone (TSH) testing for the millions of Americans with undiagnosed thyroid dysfunction (Table) (3, 4).Table 1.Recommendations of 8 ...

An international survey of screening and management of hypothyroidism during pregnancy in Latin America.

To determine how endocrinologists in Latin America deal with clinical case scenarios related to hypothyroidism and pregnancy. In January 2013, we sent an electronic questionnaire on current practice relating to management of hypothyroidism in pregnancy to 856 members of the Latin American Thyroid Society (LATS) who manage pregnant patients with thyroid disease. Subsequently, we have analyzed responses from physician members. Two hundred and ninety-three responders represent clinicians from 13 countries. All were directly involved in the management of maternal hypothyroidism and 90.7% were endocrinologists. The recommendation of a starting dose of L-thyoxine for a woman diagnosed with overt hypothyroidism in pregnancy, preconception management of euthyroid women with known thyroid autoimmunity and approach related to ovarian hyperstimulation in women with thyroid peroxidase antibodies were widely variable. For women with known hypothyroidism, 34.6% of responders would increase L-thyroxine dose by 30-50% as soon as pregnancy is confirmed. With regard to screening, 42.7% of responders perform universal evaluation and 70% recommend TSH < 2.5 mUI/L in the first trimester and TSH < 3 mUI/L in the second and third trimester as target results in known hypothyroid pregnant women. Deficiencies in diagnosis and management of hypothyroidism during pregnancy were observed in our survey, highlighting the need for improvement of specialist education and quality of care offered to patients with thyroid disease during pregnancy in Latin America.

Outcomes of Patients with Differentiated Thyroid Cancer Risk-Stratified According to the American Thyroid Association and Latin American Thyroid Society Risk of Recurrence Classification Systems

The aims of this study were to validate the proposed Latin American Thyroid Society (LATS) risk of recurrence stratification system and to compare the findings with those of the American Thyroid Association (ATA) risk of recurrence stratification system. This study is a retrospective review of papillary thyroid cancer patients treated with total thyroidectomy and radioactive iodine at a single experienced thyroid cancer center and followed according to the LATS management guidelines. Each patient was risk-stratified using both the LATS and ATA staging systems. The primary endpoints were (i) the best response to initial therapy defined as either remission (stimulated thyroglobulin [Tg] <1 ng/mL, negative ultrasonography) or persistent disease (biochemical and/or structural), and (ii) clinical status at final follow-up defined as no evidence of disease (suppressed Tg <1 ng/mL, negative ultrasonography), biochemical persistent disease (suppressed Tg >1 ng/mL in the absence of structural disease), structural persistent disease (locoregional or distant metastases), or recurrence (biochemical or structural disease identified after a period of no evidence of disease). One hundred seventy-one papillary thyroid cancer patients were included (mean age 45 ± 16 years, followed for a median of 4 years after initial treatment). Both the ATA and LATS risk stratification systems provided clinically meaningful graded estimates with regard to (i) the likelihood of achieving remission in response to initial therapy, (ii) the likelihood of having persistent structural disease in response to initial therapy and at final follow-up, (iii) the likely locations of the persistent structural disease (locoregional vs. distant metastases), (iv) the likelihood of recurrence, and (v) the likelihood of being no evidence of disease at final follow-up. The likelihood of having persistent biochemical evidence of disease was not significantly different across the staging categories. Both the ATA and LATS risk of recurrence systems effectively risk-stratify patients with regard to multiple important clinical outcomes. When used in conjunction with a staging system that predicts disease-specific mortality, either of these systems can be used to guide risk-adapted individualized initial management recommendations.

Clinical practice guidelines for the management of hypothyroidism

Hypothyroidism has long been known for its effects on different organ systems, leading to hypometabolism. However, subclinical hypothyroidism, its most prevalent form, has been recently related to cardiovascular risk and also to maternal-fetal complications in pregnant women. In these clinical practice guidelines, several aspects of this field have been discussed with the clear objectives of helping physicians treat patients with hypothyroidism, and of sharing some of our Latin American-based clinical experience. The Latin American Thyroid Society commissioned a Task Force on Hypothyroidism to develop evidence-based clinical guidelines on hypothyroidism. A systematic review of the available literature, focused on the primary databases of MedLine/PubMed and Lilacs/SciELO was performed. Filters to assess methodological quality were applied to select the best quality studies. The strength of recommendation on a scale from A-D was based on the Oxford Centre for Evidence--based Medicine, Levels of Evidence 2009, allowing an unbiased opinion devoid of subjective viewpoints. The areas of interest for the studies comprised diagnosis, screening, treatment and a special section for hypothyroidism in pregnancy. Several questions based on diagnosis, screening, treatment of hypothyroidism in adult population and specifically in pregnant women were posed. Twenty six recommendations were created based on the answers to these questions. Despite the fact that evidence in some areas of hypothyroidism, such as therapy, is lacking, out of 279 references, 73% were Grade A and B, 8% Grade C and 19% Grade D. These evidence-based clinical guidelines on hypothyroidism will provide unified criteria for management of hypothyroidism throughout Latin America. Although most of the studies referred to are from all over the world, the point of view of thyroidologists from Latin America is also given.

Management of Thyroid Dysfunction during Pregnancy and Postpartum: An Endocrine Society Clinical Practice Guideline

The aim was to update the guidelines for the management of thyroid dysfunction during pregnancy and postpartum published previously in 2007. A summary of changes between the 2007 and 2012 version is identified in the Supplemental Data (published on The Endocrine Society's Journals Online web site at http://jcem.endojournals.org). This evidence-based guideline was developed according to the U.S. Preventive Service Task Force, grading items level A, B, C, D, or I, on the basis of the strength of evidence and magnitude of net benefit (benefits minus harms) as well as the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence. The guideline was developed through a series of e-mails, conference calls, and one face-to-face meeting. An initial draft was prepared by the Task Force, with the help of a medical writer, and reviewed and commented on by members of The Endocrine Society, Asia and Oceania Thyroid Association, and the Latin American Thyroid Society. A second draft was reviewed and approved by The Endocrine Society Council. At each stage of review, the Task Force received written comments and incorporated substantive changes. Practice guidelines are presented for diagnosis and treatment of patients with thyroid-related medical issues just before and during pregnancy and in the postpartum interval. These include evidence-based approaches to assessing the cause of the condition, treating it, and managing hypothyroidism, hyperthyroidism, gestational hyperthyroidism, thyroid autoimmunity, thyroid tumors, iodine nutrition, postpartum thyroiditis, and screening for thyroid disease. Indications and side effects of therapeutic agents used in treatment are also presented.

When Thyroidologists Agree to Disagree: Comments on the 2012 Endocrine Society Pregnancy and Thyroid Disease Clinical Practice Guideline

When Thyroidologists Agree to Disagree: Comments on the 2012 Endocrine Society Pregnancy and Thyroid Disease Clinical Practice Guideline

Highlights of the Guidelines on the Management of Hyperthyroidism and Other Causes of Thyrotoxicosis

ThyroidVol. 21, No. 6 EditorialsHighlights of the Guidelines on the Management of Hyperthyroidism and Other Causes of ThyrotoxicosisGeraldo Medeiros-Neto, João H. Romaldini, and Marcos AbalovichGeraldo Medeiros-NetoExecutive Council, Latin American Thyroid Society (LATS).Senior Professor of Endocrinology, Thyroid Molecular Laboratory (LIM-25), University of São Paulo Medical School, São Paulo, Brazil.Search for more papers by this author, João H. RomaldiniProfessor of Endocrinology, School of Medicine, Catholic University of Campinas, São Paulo, Brazil.Hospital for State Civil Servants/Office of Medical Assistance for State Civil Servants (HSPE-IAMSPE), São Paulo, Brazil.Search for more papers by this author, and Marcos AbalovichExecutive Council, Latin American Thyroid Society (LATS).Endocrinology Division, Durand Hospital, Buenos Aires, Argentina.Associate Professor, Favaloro University, Buenos Aires, Argentina.Search for more papers by this authorPublished Online:10 Jun 2011https://doi.org/10.1089/thy.2011.2106.ed2AboutSectionsView articleView Full TextPDF/EPUB ToolsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View articleFiguresReferencesRelatedDetailsCited byComparative Effectiveness of Treatment Choices for Graves' Hyperthyroidism: A Historical Cohort Study Vishnu Sundaresh, Juan P. Brito, Prabin Thapa, Rebecca S. Bahn, and Marius N. Stan1 April 2017 | Thyroid, Vol. 27, No. 4 Volume 21Issue 6Jun 2011 InformationCopyright 2011, Mary Ann Liebert, Inc.To cite this article:Geraldo Medeiros-Neto, João H. Romaldini, and Marcos Abalovich.Highlights of the Guidelines on the Management of Hyperthyroidism and Other Causes of Thyrotoxicosis.Thyroid.Jun 2011.581-584.http://doi.org/10.1089/thy.2011.2106.ed2Published in Volume: 21 Issue 6: June 10, 2011PDF download

Differences Between Latin American and American Associations' Thyroid Cancer Guidelines

The recommendations of the Latin American Thyroid Society (LATS) on differentiated thyroid cancer diagnosis and management were published (1) at almost the same time as the American Thyroid Association (ATA) published their revised guidelines on thyroid cancer (2). Although we endorse the ATA guidelines, there are some differences between the two societies’ positions concerning surgical approach, risk stratification, and other issues that deserve brief comment. Our consensus reflects the heterogeneity of different countries with regard to health care resources and our experience adapting to them. For this reason, we assembled experts from Brazil (Celso Friguglietti, Laura S. Ward, Rosalinda R. Camargo, Mario Vaisman, and Eduardo Tomimori); Argentina (Fabian Pitoia, Hugo Niepomniszcz, Ruben Harach, and Alicia Gauna); Chile (Fernando Munizaga and Nelson Wolk); and Peru (Sandro Corigliano and Eduardo Pretell) who, thanks to support from LATS President (Hans Graf ) and President-Elect (Marcos Abalovich), produced a first draft based on evidence and the expert opinion on how it could be implemented in different countries. The final consensus was written after this draft circulated among LATS associates who sent many suggestions that were incorporated into the final manuscript. The main divergent points between the LATS and ATA guidelines are as follows. While LATS recommends total thyroidectomy for treating all differentiated thyroid carcinomas independent of their size, ATA suggests that a simple lobectomy may be sufficient for treating unifocal intrathyroidal papillary thyroid tumors smaller than 1 cm at their largest diameter (microcarcinomas). The LATS panel considered that, although some patients may be overtreated, total thyroidectomy precedes an adequate follow-up by allowing reliable thyroglobulin (Tg) measurements. In many Latin American countries, a proper follow-up may not be possible without reliable Tg measurements, since serial ultrasonography implies professionals specializing in imaging, still not available everywhere. Lobectomy should be considered sufficient only when a retrospective diagnosis of microcarcinoma is made after surgical treatment for other disorders of the thyroid gland. Another important difference concerning surgical treatment is the indication of lobectomy in some particular cases, such as with patients with low adherence to a treatment plan or those who live far away from medical centers, who may not return for regular follow-up. These circumstances are very characteristic of some specific regions of Latin America. The panel considered that, in such situations, the risk of death or recurrence of thyroid tumor might be lower than the burden and the risks of a chronic hypothyroid state. LATS and ATA also differ regarding postsurgical risk stratification, although guidelines from both groups are based on American Joint Committee on Cancer=Union Internationale Contre le Cancer TNM staging. LATS consensus considers three main groups of patients: very low, low, and high risk, whereas the ATA revised guidelines define low, intermediate, and high-risk patients. The LATS panel considers tumors with microscopic invasion into the perithyroidal soft tissues, cervical node metastasis, and tumors with aggressive histology (the intermediate-risk patients in the ATA guidelines) as belonging to the high-risk group, since these patients may present recurrences (3–5). Regarding radioiodine remnant ablation, there is a substantial difference between the guidelines. The ATA recommends remnant ablation only for high-risk patients; even patients with multifocal microcarcinomas are not supposed to receive remnant ablation, according to the ATA guidelines. The LATS panel also recommends remnant ablation for all high-risk patients but considers that the procedure might also benefit some low-risk patients; it is not mandatory for patients categorized as very low-risk. We leave the decision to physician, who should also take into account their own experience and the access to the proper facilities in their region (1). Only a brief consideration is given to the predictive value of pre-ablation stimulated thyroglobulin (Tg) levels in the ATA guidelines. The LATS panel considers that this first serum stimulated Tg determination after surgery is a good prognostic factor of persistent disease and should always be measured. Considering thyroid hormone replacement or suppressive therapy, the main difference between the guidelines involves low-risk patients. LATS divided these patients into two groups: very low risk, in whom serum thyrotropin (TSH) levels are maintained in the normal range, and low risk, in whom serum TSH is maintained between 0.4 and 1 mU=L. ATA recommends the serum TSH be kept between 0.1 and 0.5 mU=L in low-risk patients.

Latin American Thyroid Society recommendations for the management of thyroid nodules

Several guidelines on diagnosis and treatment of thyroid nodules and cancer have recently been published. However, recommended practices are not always appropriate to different settings or countries. The aim of this consensus was to develop Clinical Guidelines for evaluation and management of patients with thyroid nodules applicable to Latin American countries. The panel was composed by 13 members of the Latin American Thyroid Society involved with research and management of thyroid nodules and cancer from different medical centers in Latin America. The consensus was produced based on the expert opinion of the panel with use of principles of evidence-based medicine. Following a group meeting, a first draft based on the expert opinion of the panel was elaborated and later circulated among panel members for further revision. After revision, this document was submitted to all LATS members for commentaries and considerations and finally revised and refined by the authors. The final recommendations represent state of the art on management of thyroid nodules applied to all Latin American countries.

Recommendations of the Latin American Thyroid Society on diagnosis and management of differentiated thyroid cancer

The aims of these recommendations were to develop clinical guidelines for evaluation and management of patients with differentiated thyroid cancer applicable to Latin American countries. The panel was composed by 13 members of the Latin American Thyroid Society (LATS) involved with research and management of thyroid cancer from different medical centers in Latin America. The recommendations were produced on the basis of the expert opinion of the panel with use of principles of Evidence-Based Medicine. Following a group meeting, a first draft based on evidences and the expert opinions of the panel was elaborated and, later, circulated among panel members, for further revision. After, this document was submitted to the LATS members, for commentaries and considerations, and, finally, revised and refined by the authors. The final recommendations presented in this paper represent the state of the art on management of differentiated thyroid cancer applied to all Latin American countries.

Management of Graves’ orbitopathy in Latin America: an international questionnaire study compared with Europe

Management of Graves' orbitopathy (GO) and dysthyroid optic neuropathy (DON) continues to be challenging. Other surveys have been successful in elucidating trends in GO management. Knowledge of current practice by members of the Latin American Thyroid Society (LATS) who manage patients with GO was targeted by distribution of a questionnaire. We compared our results with a previously reported European Thyroid Association (ETA) survey. To determine how endocrinologists in Latin America access and treat patients with GO and compare the results with the same European survey. One hundred and two responders representing endocrinologists from 10 countries participated in the survey. Most (57%) participate in a multidisciplinary setting for GO management. Access to a surgeon for orbital decompression was available only 'within months' according to 48.3% of responders. Despite suspected DON, 32.4% were reluctant to recommend urgent referral to an eyecare physician. Steroids were preferred as the first-option therapy by 88.2% of responders (by intravenous route by 57.8% of these). The presence of diabetes reduced the use of steroids to 64.7% (P < 0.001) and increased the use of other immunosuppressive agents (from 1% to 9.8%, P < 0.01). Development of cushingoid features resulted in a reduction in steroid use to 40.2% (P < 0.001), with increased preference for irradiation (from 23.5% to 52.9%, P < 0.001) and nonsteroidal immunosuppressive drugs (from 1% to 10.8%, P < 0.01), along with a nonsignificant trend to higher indication of orbital surgery (from 24.5% to 34.3%). Some potential deficiencies in the diagnosis and management of DON and hyperthyroidism were observed in our survey, highlighting the need for improvement in specialist education and the quality of care offered to patients with GO in Latin America.

Thyroid insufficiency during pregnancy: complications and implications for screening

In 2007, clinical practice guidelines concerning the management of thyroid dysfunction during pregnancy and postpartum were published in the Journal of Clinical Endocrinology and Metabolism. They were elaborated on by a panel of experts, representative of the Latin American Thyroid Society, the Asia and Oceania Thyroid Society, the American Thyroid Association, the European Thyroid Association, the American Association of Clinical Endocrinologists and the Endocrine Society. In women not known to have thyroid dysfunction, universal screening during pregnancy is not recommended, but thyroid function tests are advised in those with prior therapeutic head or neck irradiation, a history of preterm delivery, in cases of infertility and in the presence of risk factors for thyroid disease. Risks factors for thyroid dysfunction are considered as a personal or family history of thyroid diseases, presence of thyroid antibodies (when known), personal history of autoimmune diseases and the presence of signs or symptoms suggesting hypo- or hyperthyroidism. In this review, we summarize the modifications of the pituitary–thyroid axis during pregnancy, with particular attention on thyroid insufficiency. We consider the most important risk factors for thyroid dysfunction and focus our attention on the complications for the progeny, deriving from a condition of maternal thyroid impairment. We will discuss the matters in favor of or against a thyroid-screening program at the beginning of pregnancy.

Management of Thyroid Dysfunction during Pregnancy and Postpartum: An Endocrine Society Clinical Practice Guideline

The objective is to provide clinical guidelines for the management of thyroid problems present during pregnancy and in the postpartum. The Chair was selected by the Clinical Guidelines Subcommittee (CGS) of The Endocrine Society. The Chair requested participation by the Latin American Thyroid Society, the Asia and Oceania Thyroid Society, the American Thyroid Association, the European Thyroid Association, and the American Association of Clinical Endocrinologists, and each organization appointed a member to the task force. Two members of The Endocrine Society were also asked to participate. The group worked on the guidelines for 2 yr and held two meetings. There was no corporate funding, and no members received remuneration. Applicable published and peer-reviewed literature of the last two decades was reviewed, with a concentration on original investigations. The grading of evidence was done using the United States Preventive Services Task Force system and, where possible, the GRADE system. Consensus was achieved through conference calls, two group meetings, and exchange of many drafts by E-mail. The manuscript was reviewed concurrently by the Society's CGS, Clinical Affairs Committee, members of The Endocrine Society, and members of each of the collaborating societies. Many valuable suggestions were received and incorporated into the final document. Each of the societies endorsed the guidelines. Management of thyroid diseases during pregnancy requires special considerations because pregnancy induces major changes in thyroid function, and maternal thyroid disease can have adverse effects on the pregnancy and the fetus. Care requires coordination among several healthcare professionals. Avoiding maternal (and fetal) hypothyroidism is of major importance because of potential damage to fetal neural development, an increased incidence of miscarriage, and preterm delivery. Maternal hyperthyroidism and its treatment may be accompanied by coincident problems in fetal thyroid function. Autoimmune thyroid disease is associated with both increased rates of miscarriage, for which the appropriate medical response is uncertain at this time, and postpartum thyroiditis. Fine-needle aspiration cytology should be performed for dominant thyroid nodules discovered in pregnancy. Radioactive isotopes must be avoided during pregnancy and lactation. Universal screening of pregnant women for thyroid disease is not yet supported by adequate studies, but case finding targeted to specific groups of patients who are at increased risk is strongly supported.

Management of amiodarone‐induced thyrotoxicosis in Latin America: an electronic survey

To assess diagnostic and therapeutic approaches to amiodarone-induced thyrotoxicosis (AIT) among members of the Latin American Thyroid Society (LATS). LATS members responded to an online questionnaire that presented an index case (a 62-year-old man on amiodarone, with thyrotoxic symptoms and a nodular goitre) and a variant (same patient, no goitre). About 25% of invited members responded to the questionnaire. Most respondents lived in iodine-sufficient areas and observed that amiodarone-induced hypothyroidism (AIH) is more common than AIT. Nearly all assessed TSH, and the most used combination of tests was TSH and free T4 (37%). Thyroid autoimmunity was assessed by about 90%. Interleukin-6 (IL-6) was useful to 80%. Additional tests ordered for the index case were: radioactive iodine uptake (RAIU; 57%), echo-colour Doppler sonography (ECDS; about 50%) and fine-needle aspiration biopsy (FNAB; 44%). For the variant, ECDS and RAIU were judged unhelpful by 16%. Most defined the index case as type I AIT and the variant as type II AIT, but 16% in LATS suggested a mixed form in the index case. As initial treatment, nearly all used thionamides in the index case [with potassium perchlorate (KClO(4)) in one-third], while glucocorticoids were indicated to the variant by 66%. Only about 5% considered amiodarone withdrawal unnecessary. If initial strategy is ineffective in type I AIT, KClO(4) (half) or glucocorticoids (a third) are added; in type II, glucocorticoids are indicated by most. Once euthyroidism is restored, ablative therapy is prescribed by a third of respondents for type I AIT. There are several points of disagreement among thyroidologists regarding AIT management, mainly in the radiological evaluation and the approach to the already stabilized patient if amiodarone needs to be restarted.