Sonography of the distal femoral epiphysis in the etiological diagnosis of congenital hypothyroidism.

The etiology of congenital hypothyroidism (CH) is often difficult to identify, owing mainly to limitations in currently available diagnostic tests. Characteristics of the distal femoral epiphyseal (DFE) ossification center may provide important information and help identify some causes of CH. We analyzed the contribution of DFE ultrasonography in the investigation of 11 young infants with positive screening for CH. DFE ultrasonography emerged as a simple test that helped indicate the period of onset of CH and, when associated with clinical history, hormone levels, and thyroid ultrasonography, contributed to suggest the etiology of CH.

Thyroid Nodules in Severely Obese Patients: Frequency and Risk of Malignancy on Ultrasonography.

Background: We aimed to compare the thyroid ultrasonographic findings of severely obese versus nonobese individuals, and the frequency, characteristics, and risk of malignancy in detected nodules.Design: Case-control study including 67 adults with severe obesity (body mass index [BMI] ≥ 35 kg/m2) and 67 nonobese controls (BMI < 30 kg/m2). The participants underwent ultrasound evaluation of the thyroid and cervical subcutaneous tissue. The risk of malignancy in detected nodules was determined using the American Thyroid Association (ATA) 2015 and the Thyroid Imaging Reporting and Data System (TI-RADS) classifications. Fine-needle aspiration biopsy (FNAB) was performed in nodules for which the procedure was recommended according to the ATA-2015 or TI-RADS criteria, and the cytological evaluation followed the Bethesda classification.Results: The mean BMI values in the case and control groups were 47.0 ± 6.1 kg/m2 and 22.8 ± 2.7 kg/m2, respectively. There were no differences between groups regarding sex, age, total T3, and antiperoxidase (antiTPO) antibody positivity. When compared with controls, severely obese individuals showed a greater frequency of parenchymal hypoechogenicity (p = 0.042), cervical subcutaneous tissue thickness (p < 0.001), overall frequency of thyroid nodules (p = 0.038), and frequency of multiple nodules (p = 0.013). No significant differences were observed in terms of risk of nodular malignancy according to both the ATA-2015 and TI-RADS classifications in severely obese compared with nonobese individuals.Conclusions: Severely obese individuals (versus nonobese controls) presented increased parenchymal hypoechogenicity and frequency of thyroid nodules on ultrasonographic evaluation. However, no significant differences were observed in terms of risk of nodular malignancy between both groups according to the ATA-2015 and TI-RADS criteria. Thus, ultrasonographic thyroid screening of severely obese individuals is not justified.

Sonographic evaluation of the thyroid size in neonates.

PURPOSE: To validate the use of the ratio between the total transverse diameters of the thyroid lobes (Th) and the width of the trachea (Tr)-the Th:Tr or Yasumoto ratio-as a sonographic method for estimating thyroid size, and to determine reference values for this ratio and for thyroid volume in neonates. METHODS: In this cross-sectional study, we evaluated thyroid size according to the Yasumoto ratio and the thyroid volume calculated with the ellipsoid formula in 125 healthy, euthyroid, iodine-sufficient, full-term neonates. RESULTS: The mean thyroid gland volume was 1.00 ml (95% confidence interval, 0.95-1.03 ml), and the mean Yasumoto ratio was 2.29 (95% confidence interval, 2.21-2.31). The lower- and upper-limit results falling within 2 SDs of the mean were 0.45 ml and 1.53 ml for the volume and 1.71 and 2.87 for the ratio. CONCLUSIONS: In full-term, euthyroid, iodine-sufficient neonates, the normal reference interval for thyroid volume measured on sonography was 0.45-1.53 ml and that for the Yasumoto ratio was 1.71-2.87. A ratio of 1.7 may be applied as the cutoff value for sonographic diagnosis of thyroid dysgenesis in full-term neonates with congenital hypothyroidism. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43:224-229, 2015.

Feasibility of a snowball sampling survey to study active surveillance for thyroid microcarcinoma treatment among endocrinologists and surgeons of Brazil.

OBJECTIVES: This study aims to investigate if a sampling method using virtual networks is feasible to survey AS adoption among this "hard-to-reach" population of Brazilian doctors. METHODS: An online piloted 11-point structured survey questionnaire (designed using Googleforms®) probed the actual treatment patterns for adult patients with PTMCs, including treatment decision-making nonoperative options, was undertaken between 10 November and 30 November 2020. Participants were reached by the mobile phone Application (APP) and a snowball sampling strategy was used to recruit a total of 4783 members (maximum number of potential reach), which is the total of doctors of the all 21 social media WhatsApp® groups. RESULTS: From a total of 4783 members (maximum number of potential reach), there were 657 (13.7%) doctors (actual reach) who clicked the web link of the questionnaire, out of whom 512 (10.7%) fully completed the online survey. Among the survey respondents, 361 were endocrinologists (70.5%) and 151 were surgeons (29.5%). Overall, for low-risk PTMCs in an elderly patient, 118 responders (23%) recommend AS, while 390 (76%) recommend immediate surgery as the management, including lobectomy (18.5%) and Total Thyroidectomy (58.2%). The present responders tended to recommend surgery for PTMCs that were located adjacent to the dorsal surface of the thyroid, were multiple, or raised the size during the follow-up. CONCLUSION: Using snowball sampling strategy as an innovative route to conduct surveys was feasible and applicable but the rate of response was still very low. Our data also suggests the need to investigate if AS is embraced by Brazilian doctors.

Excessive iodine intake and ultrasonographic thyroid abnormalities in schoolchildren.

High nutritional levels of iodine may induce a higher prevalence of autoimmune thyroiditis, hypothyroidism, goiter, as well as hyperthyroidism, mostly in the elderly. This study assessed thyroid volume and ultrasonographic abnormalities as well as urinary iodine excretion (UIE) in 964 schoolchildren living in an iodine-sufficient area in southern Brazil. Thyroid volume correlated with age and body surface area in boys and girls. In 76.8% of the children, UIE was above 300 microg/l, with higher levels among boys compared to girls (484.2 microg/l vs 435.3 microg/l, p < 0.001). Thyroid abnormalities detected by ultrasonography included hemiagenesis (0.5%), nodules (0.2%), cysts (0.7%), and hypoechogenicity (11.7%). Goiter was present in 1.9% of the children. Hypoechogenicity, a relevant marker of autoimmune thyroiditis, was the most common abnormality found in our study, and this may be linked to excessive iodine intake.

Association of low sodium-iodide symporter messenger ribonucleic acid expression in malignant thyroid nodules with increased intracellular protein staining.

CONTEXT: The expression of sodium iodide symporter (NIS) is required for iodide uptake in thyroid cells. Benign and malignant thyroid tumors have low iodide uptake. However, previous studies by RT-PCR or immunohistochemistry have shown divergent results of NIS expression in these nodules. OBJECTIVE: The objective of the study was to investigate NIS mRNA transcript levels, compare with NIS and TSH receptor proteins expression, and localize the NIS protein in thyroid nodules samples and their surrounding nonnodular tissues (controls). DESIGN: NIS mRNA levels, quantified by real-time RT-PCR, and NIS and TSH receptor proteins, evaluated by immunohistochemistry, were examined in surgical specimens of 12 benign and 13 malignant nodules and control samples. RESULTS: When compared with controls, 83.3% of the benign and 100% of the malignant nodules had significantly lower NIS gene expression. Conversely, 66.7% of the benign and 100% of malignant nodules had stronger intracellular NIS immunostaining than controls. Low gene expression associated with strong intracellular immunostaining was most frequently detected in malignant (100%) than benign nodules (50%; P = 0.005). NIS protein was located at the basolateral membrane in 24% of the control samples, 8.3% of the benign, and 15.4% of the malignant nodules. The percentage of benign nodules with strong TSH receptor positivity (41.6%) was higher than malignant (7.7%). CONCLUSION: We confirmed that reduced NIS mRNA expression in thyroid malignant nodules is associated with strong intracellular protein staining and may be related to the inability of the NIS protein to migrate to the cellular basolateral membrane. These results may explain the low iodide uptake of malignant nodules.

Role of 18F-fluorodeoxyglucose positron emission tomography in preoperative assessment of cytologically indeterminate thyroid nodules.

OBJECTIVE: The objective of the study was to determine the diagnostic accuracy of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) in the preoperative diagnosis of thyroid nodules with indeterminate fine-needle aspiration biopsy results. METHODS: Forty-two consecutive patients with thyroid nodules with indeterminate cytological results participated in this study. Abnormal (18)F-FDG PET uptake was assessed visually and by measuring the maximum standardized uptake value (SUVmax) in thyroid topography. All these results were compared with the final pathological results. RESULTS: The presence of focal uptake correlated with a greater risk of malignancy (P = 0.018). All 11 malignant nodules had focal uptake (sensitivity of 100%). Of the 31 patients with benign nodules, there were 19 with positive uptake (specificity of 38.7%). The pre-PET probability of cancer was 26.2% (11 of 42), and this probability increased to 36.7% after PET for those patients whose exam showed focal uptake (11 of 30). The preoperative use of (18)F-FDG PET would result in a significant reduction (39%, 12 of 31) in the number of thyroidectomies performed in patients with benign lesions. SUVmax could not improve this degree of accuracy. There was no correlation between thyroid nodule size and SUVmax value (P = 0.96). Patients with carcinomas were younger than patients with benign lesions (P = 0.048). There was no other clinical, laboratory, or ultrasonographic variable related to malignancy. CONCLUSIONS: (18)F-FDG PET provides high sensitivity to malignant lesions and may be a potentially useful tool in the evaluation of thyroid nodules with indeterminate cytological findings. For these nodules the number of unnecessary thyroidectomies in a hypothetical algorithm using (18)F-FDG PET would be reduced by 39%.

Preoperative assessment of thyroid nodules: role of ultrasonography and fine needle aspiration biopsy followed by cytology.

PURPOSE: To evaluate the preoperative assessment of thyroid nodules using ultrasound studies and cytology of nodular aspirates. SUBJECTS AND METHODS: 2,468 patients with thyroid nodules were examined from 1999 to 2005. All patients were clinically examined and underwent ultrasonography followed by fine-needle aspiration biopsy (FNAB) and cytology. RESULTS: Nodules larger than 10 mm were classified ultrasonographically in a 4-tier system and received a score according to the criterion of possible malignancy. Cytological examinations were conducted independently by 2 cytologists and classified as benign (score 1), indeterminate (score 2), suspicious (score 3), and malignant (score 6). Combining both scores, an index was generated that would indicate a higher probability of malignancy (benign, doubtful, suspicious, and malignant). Thyroid surgery was performed in 274 patients. Of those, 115 patients had a score of 2 to 5 and only 8 had a histological diagnosis of thyroid cancer (6.9%). For patients with a score of 5 (n = 51), 11.5% had a malignant lesion, and 51% of the 61 patients with a score of 6 had confirmed thyroid cancer. Of the 98 patients with a combined score of 7 to 10, 99% had a histological confirmation of malignancy. CONCLUSIONS: The index score had a sensitivity of 94.1% and specificity of 77.5%. The overall accuracy was 85.8%. Therefore, we concluded that this methodology may improve the preoperative diagnosis of thyroid cancer in nodules larger than 10 mm. Association with other methods such as color Doppler echography, serum TSH concentration, galectin-3 expression analysis, and FDG/PET scan would be useful in avoiding the higher costs of thyroid surgical procedures.

[Usefulness of ultrasound in the diagnosis and management of well-differentiated thyroid carcinoma]. / Uso da ultra-sonografia no diagnóstico e seguimento do carcinoma bem diferenciado da tireóide.

Thyroid nodules are found in the vast majority of the population, but only 5 to 10% are malignant. Ultrasonography of the thyroid, by virtue of being a straightforward, non-invasive method presenting strong correlation with macroscopic aspects of the thyroid gland, is being increasingly used to identify nodules that present a higher risk of malignancy. The presence of certain ultrasonographic characteristics such as hypoechogenicity, microcalcifications, irregular contours and central vascularization on Doppler, increase the risk of the lesion being malignant. Conversely, nodules presenting benign ultrasonographic characteristics such as hyperechogenicity and a mixed sponge-like aspect, and a concordant cytology, have a negative predictive value of 96.6%. It is, thus, important to examine all nodular lesions and to identify suspicious lesions that need biopsy, especially in multinodular glands. Ultrasonography is also highly sensitive in the identification of suspicious cervical lymph nodes during the follow-up of patients with thyroid carcinoma, even when PCI is negative and serum thyroglobulin (Tg) levels are undetectable. Tg measurement in the needle wash-out content is recommended as this has proven to be more sensitive than cytology in the diagnosis of cervical metastasis, especially where there is liquid content, and it is not affected by the presence of anti-Tg antibodies.

Feasibility of a snowball sampling survey to study active surveillance for thyroid microcarcinoma treatment among endocrinologists and surgeons of Brazil

Abstract Objectives: This study aims to investigate if a sampling method using virtual networks is feasible to survey AS adoption among this "hard-to-reach" population of Brazilian doctors. Methods: An online piloted 11-point structured survey questionnaire (designed using Googleforms®) probed the actual treatment patterns for adult patients with PTMCs, including treatment decision-making nonoperative options, was undertaken between 10 November and 30 November 2020. Participants were reached by the mobile phone Application (APP) and a snowball sampling strategy was used to recruit a total of 4783 members (maximum number of potential reach), which is the total of doctors of the all 21 social media WhatsApp® groups. Results: From a total of 4783 members (maximum number of potential reach), there were 657 (13.7%) doctors (actual reach) who clicked the web link of the questionnaire, out of whom 512 (10.7%) fully completed the online survey. Among the survey respondents, 361 were endocrinologists (70.5%) and 151 were surgeons (29.5%). Overall, for low-risk PTMCs in an elderly patient, 118 responders (23%) recommend AS, while 390 (76%) recommend immediate surgery as the management, including lobectomy (18.5%) and Total Thyroidectomy (58.2%). The present responders tended to recommend surgery for PTMCs that were located adjacent to the dorsal surface of the thyroid, were multiple, or raised the size during the follow-up. Conclusion: Using snowball sampling strategy as an innovative route to conduct surveys was feasible and applicable but the rate of response was still very low. Our data also suggests the need to investigate if AS is embraced by Brazilian doctors.

[Low-risk differentiated thyroid carcinoma--literature review and management guidelines]. / Câncer diferenciado da tiróide de baixo risco--revisão do estado atual da literatura e proposta de conduta.

The trend of increasing thyroid cancer has been recognized in Brazil as well as all over the world for several decades. The large use of simple and effective diagnostic tools has significantly contributed to this trend. It is estimated that small carcinomas found at surgery for benign thyroid disorders and by ultrasonography will be identified at greater frequency in the further years. Part of these tumors occurs in low-risk patients that may benefit of less aggressive management strategies. However, the characterization of low-risk patient is still confusing and we lack adequate markers to tell apart patients that may present a troublesome progression of the disease. Furthermore, the use of new follow-up methods has recently changed some guidelines. A multidisciplinary team, including basic scientists, endocrinologists, nuclear medicine physicians, thyroid surgeons and endocrine pathologists reviewed the pertinent literature and, based on their experience, propose some management guidelines for Brazilian patients with low-risk thyroid carcinomas.

[Cost-effectiveness of the clinical treatment of Grave's disease in a public University Hospital: a retrospective analysis and prospective projection for a therapeutic approach]. / Impacto médico-social do tratamento medicamentoso da moléstia de Graves-Basedow em Hospital Público Universitário: avaliação retrospectiva e projeção prospectiva de conduta terapêutica.

The aim of the present study was to evaluate a new proposal for increasing compliance to the clinical management of patients with Graves' disease (GD) in a large and public University Hospital. The patients were carefully selected (no previous GD treatment, goiter volume less than 6 mL must be living in the metro area of São Paulo), received medication at no cost, were contacted frequently by the social worker and alerted for the date of consultation and only referred to a single endocrinologist during all phases of treatment. We recruited 229 patients with GD that were initially treated with methimazole (MMI--60 mg q.d) in a single daily dose followed by a combination of MMI (20 mg) plus L-T4 (100 microg) daily for 24 months. Only 83 patients (36.2%) completed the protocol and were subdivided in: Group 1 (n= 34) that were in remission for 3 years after discontinuation of the MMI and Group 2 (n= 49) that presented recurrence of GD between 2 and 36 months without MMI. Predictive factors associated with remission were: decrease of the glandular volume, serum TG< 40 ng/mL and normal TRAb values. We concluded that in spite of a careful protocol planned to increase compliance, more than 60% of patients with GD did not complete the therapeutic trial and were referred for radioiodine treatment. The solution for this low therapeutic success for GD should be the possible identification of factors that would indicate patients that are not inclined to follow a long period of clinical therapy.

Impact of nutritional iodine optimization on rates of thyroid hypoechogenicity and autoimmune thyroiditis: a cross-sectional, comparative study.

BACKGROUND: Since several countries have established mandatory food iodine fortification, there has been a decrease in rates of iodine deficiency disorders in parallel with an increase in prevalence of autoimmune thyroid diseases. This study compared the nutritional iodine status and the prevalence of autoimmune thyroiditis and thyroid hypoechogenicity on ultrasound in schoolchildren in São Paulo (Brazil) in two distinct periods of time in which fortified salt had different concentrations of iodine. METHODS: We conducted a cross-sectional study evaluating 206 children aged 7-14 years and without a history of thyroid disease. Assessments included measurements of thyrotropin (TSH), free thyroxine, antithyroperoxidase (anti-TPO), and antithyroglobulin (anti-TG) antibodies, urinary iodine concentration, and thyroid ultrasound. RESULTS: Mean urinary iodine concentration was 165.1 µg/L. Eleven children (5.3%) were diagnosed with autoimmune thyroiditis based on at least two of four criteria adopted in our study: positive anti-TPO or anti-TG antibody, hypoechogenicity of the thyroid parenchyma on ultrasound, and a TSH >4.0 µU/mL. Comparing our results with those from a similar study conducted during a period in which concentrations of iodine in the salt were higher (median urinary iodine concentration >300 µg/L), we observed a trend toward a lower prevalence of autoimmune thyroiditis, although no definitive conclusion could be established. CONCLUSION: The current nutritional iodine status in our cohort was within optimal levels and lower than levels found in 2003. The prevalence of autoimmune thyroiditis seems to be decreasing in parallel with a decrease in iodine intake, although we could not reach a definitive conclusion.

[Ultrasonographic evaluation of thyroid nodules: comparison with cytologic and histologic diagnosis]. / Avaliação ultra-sonográfica dos nódulos tireóideos: comparação com exame citológico e histopatológico.

The purpose of this study was to evaluate our ultrasonographic classification of thyroid nodules, based on echo structure, echogenicity, calcification, margin and analysis of the surrounding parenchyma. From January 1998 to January 2002, 2,468 consecutive patients with thyroid nodules were referred for thyroid ultrasonography and ultrasound-guided fine needle aspiration biopsy (USFNAB) in our Thyroid Unit. Among 1,039 nodules classified as benign on ultrasound, 998 (96.1%) were also benign on cytology, 37 (3.6%) were suspicious and only 4 (0.4%) were malignant. On the other hand, among 153 nodules classified as suspicious on ultrasound, 20 (13.1%) were suspicious and 88 (57,5%) were malignant on cytology. Of the 71 nodules suspicious on ultrasound submitted to surgery, 67 (94.3%) were malignant and 56 (96.6%) of 58 nodules considered benign were benign on pathologic studies. In conclusion, we advocate USFNAB in nodules classified as indeterminate or suspicious. Nodules classified as benign may be followed up at periodic intervals.

[Echographic evaluation of the thyroid gland and urinary iodine concentration in school children from various regions of the State of São Paulo, Brazil]. / Avaliação ultra-sonográfica da tireóide e determinação da iodúria em escolares de diferentes regiões do Estado de São Paulo.

We have examined, by ultrasonographic studies, the thyroid gland of 844 schoolchildren, aged between 6 and 14 years old (423 girls, 421 boys). There was a progressive increase of the thyroid volume with aging with a positive and significant correlation with the body surface area. The presence of enlarged thyroid gland was rarely seen, being present in only 1.6% of the studied cohort. A few thyroid gland abnormalities were noticed such as hemiagenesia (4 children), nodules and cysts and hypoechogenicity (total: 1.4% of all subjects examined). It was clearly demonstrated that the urinary excretion of iodine was elevated being above 300 microg Iodine/L in 53% of the schoolchildren examined. Assays for the iodine concentration in the domestic salt samples revealed values between 28.1 and 63.3 mgI/kg of salt. We concluded that the schoolchildren population of the State of São Paulo may be under an excessive daily ingestion of iodine. This may induce, if extrapolated to the general population, subclinical hyperthyroidism in the elderly and possibly an increment in the prevalence of chronic autoimmune thyroiditis.

Approach to and treatment of goiters.

The main causes of simple diffuse goiter (SDG) and multinodular goiter (MNG) are iodine deficiency, increase in serum thyroid-stimulating hormone (TSH) level, natural goitrogens, smoking, chronic malnutrition, and lack of selenium, iron, and zinc. Increasing evidence suggests that heredity is equally important. Treatment of SDG and MNG still focuses on L-thyroxine-suppressive therapy surgery. Radioiodine alone or preceded by recombinant human TSH stimulation is widely used in Europe and other countries. Each of these therapeutic options has advantages and disadvantages, with acute and long-term side effects.

[Ultrasonographic evaluation of the thyroid, determination of ioduria and iodine concentration in kitchen salt used by schoolchildren in Ribeirão Preto, São Paulo, Brazil]. / Avaliação ultrassonográfica da tireoide, determinação da iodúria e concentração de iodo em sal de cozinha utilizado por escolares de Ribeirão Preto, São Paulo, Brasil.

OBJECTIVE AND METHODS: Previous studies have pointed out that Ribeirão Preto, São Paulo, is an area of borderline iodine deficiency, later becoming a region of excessive iodination. In a reevaluation of the iodine status of the city in 2007-2008, 300 schoolchildren aged 8 to 10 years were evaluated, from 3 schools of 3 different socioeconomic levels who were submitted to the determination of iodine concentration in urine samples and in kitchen salt and thyroid ultrasound. RESULTS AND CONCLUSION: Among boys and girls ioduria was higher in the school of highest socioeconomic level compared to the others, with a significant difference in the ages 8 and 10 years for boys with ranges : p < 0,0001 and p = 0,0106, respectively; and in the ages 8 and 9 years for girls with ranges: p = 0,0024 and p = 0,0154, respectively. Median iodine concentrations in samples of kitchen salt ranged from 26.6 to 27.8 mg iodine/kg and did not differ between the schools studied. Ultrasound evaluation revealed that 15,6% of thyroids examined were hypoechoic, suggesting that these glands may present changes in the architecture not reflected yet in their volume.

High prevalence of side effects after recombinant human thyrotropin-stimulated radioiodine treatment with 30 mCi in patients with multinodular goiter and subclinical/clinical hyperthyroidism.

BACKGROUND: Treatment of multinodular goiters (MNGs) is highly controversial. Radioiodine (RAI) therapy is a nonsurgical alternative for the elderly who decline surgery. Recently, recombinant human thyrotropin (rhTSH) has been used to augment RAI uptake and distribution. In this study, we determined the outcome of 30 mCi RAI preceded by rhTSH (0.1 mg) in euthyroid (EU) and hyperthyroid (subclinical/clinical) patients with large MNGs. METHODS: This was a prospective cohort study. Forty-two patients (age, 43-80 years) with MNGs were treated with 30 mCi RAI after stimulation with 0.1 mg of rhTSH. Patients were divided into three groups, according to thyroid function: EU (n = 18), subclinically hyperthyroid (SC-H, n = 18), and clinically hyperthyroid (C-H, n = 6). All patients underwent a 90-day low-iodine diet before treatment, and those with clinical hyperthyroidism received methimazole 10 mg daily for 30 days. Serum TSH, free thyroxine (FT4), total triiodothyronine (TT3), and thyroglobulin were measured at baseline and at 24, 48, 72, 168 hours, and 1, 3, 6, 9, 12, 18, 24, and 36 months after therapy. Thyroid volume was assessed by computed tomography at baseline and every 6 months. RESULTS: Patients had high iodine urinary excretion (308 +/- 108 microg I/L) at baseline. TSH levels at baseline were within the normal range (1.5 +/- 0.7 microU/mL) in the EU group and suppressed (<0.3 microU/mL) in the SC-H and C-H groups. After rhTSH, serum TSH peaked at 24 hours reaching 12.4 +/- 5.85 microU/mL. After RAI administration, patients in both hyperthyroid groups had a higher increase in FT4 and TT3 compared with those in the EU group (p < 0.001). Thyroglobulin levels increased equally in all three groups until day 7. Thyroid volume decreased significantly in all patients. Side effects were more common in the SC-H and C-H groups (31.4% and 60.4%, respectively) compared with EU patients (17.8%). Permanent hypothyroidism was more prevalent in the EU group (50%) compared with the SC-H (11%) and C-H (16.6%) groups. CONCLUSIONS: Patients with MNG may have subclinical and clinical nonautoimmune iodine-induced hyperthyroidism. Despite a low-iodine diet and therapy with methimazole, hyperthyroid patients have a significantly higher increase in FT4 and TT3 levels after RAI ablation. This can lead to important side effects related mostly to the cardiac system. We strongly advise that patients with SC-H and C-H be adequately treated with methimazole and low-iodine diet aiming to normalize their hyperthyroid condition before rhTSH-stimulated treatment with RAI.

The prevalence of thyroid dysfunction in elderly cardiology patients with mild excessive iodine intake in the urban area of São Paulo.

OBJECTIVES: To evaluate the prevalence of thyroid dysfunction in elderly cardiac patients in an outpatient setting. SUBJECTS AND METHODS: A total of 399 consecutive patients (268 women, age range 60-92 years) who were followed at Heart Institute were evaluated for thyroid dysfunction with serum free T4, TSH, anti-Peroxidase antibodies, urinary iodine excretion measurements and thyroid ultrasound. RESULTS: Hyperthyroidism (overt and subclinical) was present in 29 patients (6.5%), whereas hypothyroidism (overt and subclinical) was found in 32 individuals (8.1%). Cysts were detected in 11 patients (2.8%), single nodules were detected in 102 (25.6%), and multinodular goiters were detected in 34 (8.5%). Hashimoto's thyroiditis was present in 16.8% patients, most of whom were women (83.6%). The serum TSH increased with age and was significantly higher (p= <0.01) in patients, compared to the normal control group. No significant differences in serum TSH and free T4 values were observed when patients with atrial fibrillation (AF) where compared with those without arrhythmia. The median urinary iodine levels were 210 microg/L (40-856 microg/L), and iodine levels were higher in men than in women (p<0.01). Excessive iodine intake (urinary iodine >300 microg/L) was observed in one-third of patients (30.8%). CONCLUSIONS: Elderly patients have a higher prevalence of both hypo- and hyperthyroidism as well as thyroid nodules when compared with the general population. About one-third of the older patients had elevated urinary secretion of iodine and a higher prevalence of chronic Hashimoto's thyroiditis. It is recommended that ultrasonographic studies, tests for thyroid function and autoimmunity should be evaluated in elderly 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.