Determinación de las características funcionales de los nódulos tiroideos mediante imágenes de medicina nuclear en pacientes que acudieron al Instituto de Investigaciones en Ciencias de la Salud - UNA, en el periodo 2016-2019 / Determination of the functional characteristics of thyroid nodules through nuclear medicine images in patients, who attended the Instituto de Investigaciones en Ciencias de la Salud - UNA, in the period 2016-2019

nuclear permiten visualizar la estructura y función de un órgano, tejido, hueso o sistema dentro del cuerpo, entre ellos la glándula tiroidea, la cual puede presentar un nódulo tiroideo y este es importante diagnosticar por su potencial malignidad. Objetivo: Determinar las características funcionales de los nódulos tiroideos en 183 pacientes que asistieron al Servicio de Medicina Nuclear del Instituto de Investigaciones en Ciencias de la Salud - UNA durante el período de noviembre del 2016 - noviembre del 2019. Metodología: Fue utilizada la gammacámara SPECT doble cabezal, siguiendo protocolo estandarizado, con administración de pertecnetato de sodio. Resultados: Se observó que la gran mayoría de los pacientes corresponden al sexo femenino 89%, así como que el 64% provienen de la capital y del departamento central; las patologías detectadas corresponden a bocio en 82%, 15% a nódulos (hipercaptantes, hipocaptantes y autónomos) y casos particulares de tiroiditis, tiroides ectópica y adenoma tóxico. La medicina nuclear está directamente involucrada tanto en el diagnóstico como en el tratamiento de la enfermedad tiroidea, por lo que se requiere una comprensión de la fisiopatología y el manejo de los trastornos de la tiroides, de manera a que las políticas de salud pública sean implementadas para el fortalecimiento de la lucha contra estas enfermedades. Conclusión: El trabajo de investigación realizado comprobó que un mayoritario porcentaje de participantes de sexo femenino (89%), con enfermedades tiroideas asistieron al IICS/UNA, y que la frecuencia de bocio entre la totalidad de pacientes que participaron de este estudio fué de 151/183 (82%), los pacientes provenían en su mayoría de hospitales de referencia del departamento Central y coinciden con la localización geográfica de los domicilios de los pacientes, quienes provenían principalmente del mismo departamento Central 118/183 (64%), no obstante también participaron del trabajo de investigación pacientes provenientes de otros departamentos del país. Palabras claves: Diagnóstico, medicina nuclear, tiroides, tecnología nuclear en salud, SPECT

Introduction: The images obtained by nuclear medicine allow to visualize the structure and function of an organ, tissue, bone or system inside the body, including the thyroid gland, which can present a thyroid nodule and this is important to diagnose for its potential malignancy. Objective: To determine the functional characteristics of the thyroid nodules were determined in 183 patients, who attended the Nuclear Medicine Service at the Instituto de Investigaciones en Ciencias de la Salud during the period of November 2016 - November 2019. Methodology: It was used the dual head SPECT gamma camera following a standardized protocol with administration of sodium pertechnetate. Result: It was observed that most of the patients corresponded to the female sex 89 %, as well as that 64% came from the capital and the central department. The pathologies detected corresponded to goiter in 82%, 15% to nodules (hypercaptant, hypocaptant and autonoms) and particular cases of thyroiditis, ectopic thyroid and toxic adenoma. Nuclear medicine is directly involved both in the diagnosis and in the treatment of thyroid disease, therefore it requires an understanding of the pathophysiology and management of thyroid disorders in order that public health policies are implemented for strengthening the fight against these diseases. Conclusion: The research carried out showed that a majority percentage of female participants (89%), with thyroid diseases attended IICS / UNA, and the frequency of goiter among all patients who participated in this study was 151/183 ( 82%), the patients mostly they came the reference hospitals in the Central department and coincide with the geographic location of the patients' homes, who tested mainly from the same Central department 118/183 (64%), also participate in the research work patients from other departments of the country. Keywords: Diagnosis, nuclear medicine, thyroid, health technology, SPECT.

Self-perception of swallowing by patients with benign nonsurgical thyroid disease. / Autopercepção da deglutição em pacientes com doença tireoidiana benigna não cirúrgica.

PURPOSE: To verify the frequency of swallowing complaints in patients with benign nonsurgical thyroid disease and compare the self-perception of swallowing disorder intensity between different types of thyroid disease. METHODS: The study sample comprised 39 women aged 19-58 years (38.54 ± 10.74) with hypothyroidism (n=22; 56.4%) or thyroid nodules (n=17; 43.6%). Presence and type of swallowing complaint and self-perception of swallowing disorder intensity were investigated by means of self-ratings recorded on a 100-millimeter visual analog scale. The data were analyzed by descriptive measures and the Mann-Whitney nonparametric test was used to compare the self-perception of swallowing disorder intensity between both clinical diagnoses of thyroid disease. The level of 5% was adopted for statistical significance. RESULTS: Twenty-six (66.7%) individuals reported the following swallowing complaints: pharyngolaryngeal stasis sensation (37.15%), chocking (34.29%), and odynophagia (28.57%). The mean value of self-perception of swallowing disorder intensity by the visual analog scale was 59.35 (± 27.38) millimeters. No difference in self-perception was reported between the clinical diagnoses of thyroid disease. CONCLUSION: In this sample, swallowing complaint was frequently observed in patients with benign nonsurgical thyroid disease. Moderate self-perception of swallowing disorder intensity was reported regardless of the clinical diagnosis of thyroid disease.

Efficacy and safety of a single radiofrequency ablation of solid benign non-functioning thyroid nodules

ABSTRACT Objective The objective of our study is to evaluate the clinical outcomes and safety of radiofrequency thermal ablation (RFA) for benign thyroid nodules (BTNs) over a 1-year follow-up. Subjects and methods This is a monocentric retrospective study. Forty-eight patients with solid, non-functioning BTNs were treated by RFA using a 17G internally cooled electrode. We categorized thyroid nodules as small (≤ 12 mL), medium (12 to 30 mL), or large (over 30 mL). BTNs volume reduction, thyroid function, cosmetic and compressive score changes and side effect evaluation at 6 and 12 months were evaluated. Results BTN volume decreased significantly from baseline to 6 (mean percentage decrease of BTN volume was 66.8 ± 13.6%, p < 0.001). At 12 months, the mean percentage reduction of BTN volume compared to six months was 13.7 ± 17.1% (p < 0.001). At 6-month, symptom score had improved significantly (p < 0.001) while it does not change significantly between 6 and 12 months. In particular, symptom score improved significantly in the medium (p < 0.001) and large (p < 0.01) subgroups. Cosmetic score improved significantly between baseline and 6 months (p < 0.001) and between 6 and 12 months (p < 0.01). In all the subgroups, cosmetic score improved significantly between baseline and 6 months, while between 6 and 12 months it improved significantly only in the large group (p < 0.05). RFA was well tolerated. Only one patient experienced permanent right paramedian vocal cord palsy. Conclusions A single RFA treatment was effective in reducing BTNs volume, in particular small and medium nodules. Cosmetic score improved in all treated BTNs while symptom score only got better in the medium and large BTNs.

Efficacy and safety of a single radiofrequency ablation of solid benign non-functioning thyroid nodules.

OBJECTIVE: The objective of our study is to evaluate the clinical outcomes and safety of radiofrequency thermal ablation (RFA) for benign thyroid nodules (BTNs) over a 1-year follow-up. SUBJECTS AND METHODS: This is a monocentric retrospective study. Forty-eight patients with solid, non-functioning BTNs were treated by RFA using a 17G internally cooled electrode. We categorized thyroid nodules as small (≤ 12 mL), medium (12 to 30 mL), or large (over 30 mL). BTNs volume reduction, thyroid function, cosmetic and compressive score changes and side effect evaluation at 6 and 12 months were evaluated. RESULTS: BTN volume decreased significantly from baseline to 6 (mean percentage decrease of BTN volume was 66.8 ± 13.6%, p < 0.001). At 12 months, the mean percentage reduction of BTN volume compared to six months was 13.7 ± 17.1% (p < 0.001). At 6-month, symptom score had improved significantly (p < 0.001) while it does not change significantly between 6 and 12 months. In particular, symptom score improved significantly in the medium (p < 0.001) and large (p < 0.01) subgroups. Cosmetic score improved significantly between baseline and 6 months (p < 0.001) and between 6 and 12 months (p < 0.01). In all the subgroups, cosmetic score improved significantly between baseline and 6 months, while between 6 and 12 months it improved significantly only in the large group (p < 0.05). RFA was well tolerated. Only one patient experienced permanent right paramedian vocal cord palsy. CONCLUSIONS: A single RFA treatment was effective in reducing BTNs volume, in particular small and medium nodules. Cosmetic score improved in all treated BTNs while symptom score only got better in the medium and large BTNs.

Autopercepção da deglutição em pacientes com doença tireoidiana benigna não cirúrgica / Self-perception of swallowing by patients with benign nonsurgical thyroid disease

RESUMO Objetivo verificar a frequência de queixa para deglutir em pacientes com doença tireoidiana benigna não cirúrgica e comparar a autopercepção de intensidade da alteração de deglutição em diferentes tipos de doença tireoidiana. Método a amostra do estudo foi composta por 39 mulheres com idades entre 19 e 58 anos (38,54 ± 10,74 anos) e diagnóstico de hipotireoidismo (n=22; 56,4%) ou nódulos tireoidianos (n=17; 43,6%). Investigou-se a presença de queixa, tipo de queixa e autopercepção da intensidade da alteração de deglutição por meio da escala analógico-visual de 100 milímetros. Os dados foram analisados de forma descritiva e para comparar a autopercepção entre os diferentes diagnósticos clínicos utilizamos o teste não paramétrico de Mann-Whitney. O nível de significância foi de 5%. Resultados vinte e seis (66,7%) participantes relataram queixa para deglutir. As queixas referidas foram sensação de estase em região laringofaríngea (37,15%), engasgo (34,29%) e odinofagia (28,57%). O valor médio da autopercepção de intensidade da alteração de deglutição por meio da escala analógico-visual foi 59,35 (± 27,38) milímetros. A autopercepção não foi diferente entre os diagnósticos clínicos de doença tireoidiana. Conclusão nessa amostra, queixas para deglutir foram frequentes em mulheres com doenças tireoidianas benignas não cirúrgicas. Essas pacientes percebem a alteração de forma moderada, independentemente do diagnóstico clínico da patologia tireoidiana.

ABSTRACT Purpose To verify the frequency of swallowing complaints in patients with benign nonsurgical thyroid disease and compare the self-perception of swallowing disorder intensity between different types of thyroid disease. Methods The study sample comprised 39 women aged 19-58 years (38.54 ± 10.74) with hypothyroidism (n=22; 56.4%) or thyroid nodules (n=17; 43.6%). Presence and type of swallowing complaint and self-perception of swallowing disorder intensity were investigated by means of self-ratings recorded on a 100-millimeter visual analog scale. The data were analyzed by descriptive measures and the Mann-Whitney nonparametric test was used to compare the self-perception of swallowing disorder intensity between both clinical diagnoses of thyroid disease. The level of 5% was adopted for statistical significance. Results Twenty-six (66.7%) individuals reported the following swallowing complaints: pharyngolaryngeal stasis sensation (37.15%), chocking (34.29%), and odynophagia (28.57%). The mean value of self-perception of swallowing disorder intensity by the visual analog scale was 59.35 (± 27.38) millimeters. No difference in self-perception was reported between the clinical diagnoses of thyroid disease. Conclusion In this sample, swallowing complaint was frequently observed in patients with benign nonsurgical thyroid disease. Moderate self-perception of swallowing disorder intensity was reported regardless of the clinical diagnosis of thyroid disease.

A Novel Microvascular Flow Technique: Initial Results in Thyroids.

To evaluate the flow imaging capabilities of a new prototype ultrasound (US) image processing technique (superb micro-vascular imaging [SMI]; Toshiba Medical Systems, Tokyo, Japan) for depiction of microvascular flow in normal thyroid tissue and thyroid nodules compared with standard color and power Doppler US imaging.Ten healthy volunteers and 22 patients, with a total of 25 thyroid nodules, scheduled for US-guided fine needle aspiration were enrolled in this prospective study. Subjects underwent US examination consisting of grayscale, color and power Doppler imaging (CDI and PDI) followed by color and monochrome SMI and pulsed Doppler. SMI is a novel, microvascular flow imaging mode implemented on the Aplio 500 US system (Toshiba). SMI uses advanced clutter suppression to extract flow signals from large to small vessels and depicts this information at high frame rates as a color overlay image or as a monochrome map of flow. Two radiologists independently scored still images and digital clips for overall flow detection, vessel branching details and noise on a visual-analog scale of 1 (worst) to 10 (best).For the volunteers SMI visualized microvasculature with significantly lower velocity than CDI and PDI (P < 0.012). In all thyroid nodules, SMI demonstrated microvascular flow with significantly higher image scores and provided better depiction of the vessel branching details compared with CDI and PDI (P < 0.0001). Clutter noise was significantly higher in monochrome SMI mode than in the other modes, including color SMI (P < 0.001).The novel SMI mode consistently improved the depiction of thyroid microvascular flow compared with standard CDI and PDI.

Thyroid function, autoimmunity and nodules in hematological malignancies.

OBJECTIVE: Hematological malignancies encompass a large spectrum of disease entities whose treatment by chemo/radiotherapy could lead to thyroid complications. To the best of our knowledge, no study has simultaneously addressed thyroid function, autoimmunity and nodularity. Therefore, we decided to conduct one. MATERIALS AND METHODS: We evaluated 82 Caucasian patients (36 women and 46 men), who were treated at our Oncology division for hematological malignancies (multiple myeloma, chronic myeloid leukemia, chronic lymphatic leukemia, non-Hodgkin lymphoma and polycythemia vera) and compared them with a control group of 104 patients. Patients who had received or were receiving external head/neck radiotherapy were excluded. All oncological patients and control individuals underwent thyroid ultrasonography and thyroid function and autoimmunity tests. RESULTS: A lower prevalence of enlarged thyroid and nodules were found in patients with respect to controls. The rate of thyroid nodules was the highest in multiple myeloma and polycythemia vera, and the lowest in chronic lymphatic leukemia. Non-Hodgkin lymphoma patients had the smallest thyroid nodules while men with multiple myeloma the biggest ones. No patient had hypothyroidism, while 5.6% of patients had subclinical hyperthyroidism. In contrast, within the control group the rates of hypothyroidism and hyperthyroidism, overt and subclinical, were 3.8%, 20.2%, 0% and 0% respectively. Moreover, the overall rate of thyroid autoantibody positiveness in patients was significantly lower than controls. CONCLUSION: In our experience, we found a significantly lower prevalence of thyroid abnormalities in hematologic patients who underwent chemotherapy, but not radiotherapy, with respect to controls.

[Thyroid and pregnancy]. / Tireóide e gravidez.

Pregnancy is associated with an increased requirement of hormone secretion by the thyroid, within the first weeks after conception. To this greater demand to occurs, pregnancy induces a series of physiological changes that affect thyroid function and, consequently, the tests of glandular function. For normal pregnant women living in areas with a sufficient supply of iodine, this challenge regarding the adjustment of thyroid hormone releases to this new state of equilibrium and its maintenance until the end of pregnancy it meets no difficulties. However, among women with impaired thyroid function due to some thyroid disease or among women residing in areas with an insufficient iodine supply, this does not occur. The management of thyroid dysfunction during gestation requires special considerations, since both hypothyroidism and hyperthyroidism can lead to maternal and fetal complications. In addition, thyroid nodules are detected at reasonable frequency among pregnant women, a fact that requires a differential diagnosis between benign and malignant growths during the pregnancy itself.

Tireóide e gravidez / Thyroid and pregnancy

A gravidez está associada com a necessidade aumentada de secreção hormonal pela tireóide desde as primeiras semanas após a concepção. Para que esta maior demanda ocorra, a gestação induz uma série de alterações fisiológicas que afetam a função tireoidiana e, portanto, os testes de avaliação da função glandular. Para as mulheres grávidas normais que vivem em áreas suficientes em iodo, este desafio em ajustar a liberação de hormônios tireoidianos para o novo estado de equilíbrio e manter até o término da gestação, geralmente, ocorre sem dificuldades. Entretanto, em mulheres com a capacidade funcional da tireóide prejudicada por alguma doença tireoidiana ou naquelas que residem em áreas de insuficiência iódica, isso não ocorre. O manejo de disfunções tireoidianas durante a gestação requer considerações especiais, pois tanto o hipotireoidismo quanto o hipertireoidismo podem levar a complicações maternas e fetais. Além disso, nódulos tireoidianos são detectados, com certa freqüência, em gestantes, o que pode gerar a necessidade do diagnóstico diferencial entre benignos e malignos ainda durante a gestação.

Pregnancy is associated with an increased requirement of hormone secretion by the thyroid, within the first weeks after conception. To this greater demand to occurs, pregnancy induces a series of physiological changes that affect thyroid function and, consequently, the tests of glandular function. For normal pregnant women living in areas with a sufficient supply of iodine, this challenge regarding the adjustment of thyroid hormone releases to this new state of equilibrium and its maintenance until the end of pregnancy it meets no difficulties. However, among women with impaired thyroid function due to some thyroid disease or among women residing in areas with an insufficient iodine supply, this does not occur. The management of thyroid dysfunction during gestation requires special considerations, since both hypothyroidism and hyperthyroidism can lead to maternal and fetal complications. In addition, thyroid nodules are detected at reasonable frequency among pregnant women, a fact that requires a differential diagnosis between benign and malignant growths during the pregnancy itself.

Esclerose: uma opção de tratamento para os nódulos tireoidianos císticos / Sclerosis: an option for treatment of cystic thyroid nodules

OBJETIVO: Verificar o efeito da injeção percutânea de etanol guiada por ultra-sonografia no tratamento dos nódulos tireoidianos císticos. MATERIAIS E MÉTODOS: Comparou-se o volume de 34 nódulos benignos císticos, em 30 pacientes (26 do sexo feminino e quatro do sexo masculino), antes e uma média de 3,9 meses depois da alcoolização. O volume inicial dos nódulos foi avaliado por dois observadores, que realizaram a ultra-sonografia em momentos diferentes, sem qualquer informação prévia a respeito do tamanho dos nódulos, cuja finalidade foi conhecer a variação interobservador das medidas ecográficas. RESULTADOS: A média de volume dos nódulos antes do tratamento foi de 12,3 ± 18,0 ml. A média de redução de volume foi de 74,0 ± 26,1 por cento (p = 0,0001), e 20,6 por cento (7/34) deles desapareceram. Não houve correlação entre o volume inicial e o percentual de redução dos nódulos. A média de variação das medidas interobservadores foi de 0,5 ml para um alfa de 5 por cento. Dor moderada, no momento da aplicação, foi a complicação mais freqüente. CONCLUSÃO: A injeção percutânea de etanol é uma opção segura e eficaz no tratamento dos nódulos tireoidianos císticos.

OBJECTIVE: To check the effect of ultrasound-guided percutaneous ethanol injection for treatment of cystic thyroid nodules. MATERIALS AND METHODS: A comparison was made of the volume of 34 benign cystic nodules in 30 patients (26 female, four male), before and 3.9 months (on average) after alcoholization. For the purpose of finding out interobserver variations in echographic measurements, the initial volume of the nodules was assessed by means of ultrasound at different moments, by two observers, without any previous knowledge on the nodules size. RESULTS: Mean volume of nodules before treatment was 12.3 ± 18.0 ml. Mean reduction rate in nodules after alcoholization was 74.0 ± 26.1 percent (p < 0.0001) and 7/34 (20.6 percent) of the nodules disappeared. There was no correlation between nodules size and reduction rate. The average interobserver nodule measurement variation was 0.5 ml, for an alpha of 5 percent. Moderate pain at the time of injection was the most frequent complication. CONCLUSION: Ultrasound-guided percutaneous ethanol injection is a safe and effective option for treatment of cystic thyroid nodules.

Los trastornos tiroideos en la mujer / Thyroid malfunction in womwn

La prevalencia de trastornos tiroideos en la mujer es elevada y existe una marcada preponderancia que se ha relacionado con una mayor susceptibilidad a alteraciones de la autoinmunidad. Los trastornos tiroideos presentan como características su aparición insidiosa y la baja especificidad de sus manifestaciones. Por ello, se recomienda sospechar patología tiroidea en caso de depresión posparto, alteraciones menstruales, síndrome de amenorrea con galactorrea, pubertad precoz o retardada, esterilidad inexplicable o aborto de repetición. La dificultad en el diagnóstico clínico es compensada por la accesibilidad y relativa facilidad del diagnóstico biológico mediante las pruebas de función tiroidea, principalmente la medición de TSH y FT4, por lo que es útil considerar a estas pruebas en el estudio de los trastornos ginecológicos. Un diagnóstico precoz y oportuno resolverá en las mejores condiciones los trastornos ginecológicos originados por el mal funcionamiento de la glándula tiroides.

[Thyroid malfunction in women]. / Los trastornos tiroideos en la mujer.

The prevalence of thyroid dysfunctions is high in women, this female preponderance has been related with a bigger susceptibility to autoimmune abnormalities. Clinical features of thyroid disease have poor specificity and insidious onset. It is recommended to suspect thyroid pathology in the event of postpartum depression, menstrual abnormalities, amenorrhea, galactorrhea, precocious or delayed sexual development, inexplicable sterility or habitual abortus. The difficult in the clinical diagnosis is compensated by the accessibility and relative easiness of the biological diagnosis by means of the thyroid function tests, mainly the measurements of TSH and FT4 levels; thus, gynecological evaluations should be completed by obtaining thyroid function test. An opportune diagnosis of thyroid illness will solve under the best conditions the gynecological dysfunctions.

Sistema enzimático gerador de peróxido de hidrogênio: NADPH oxidase na tireóide humana / Enzimatic system generator of hydrogen peroxide: NADPH oxidase in human thyroid

No presente estudo avaliamos a atividade geradora de peróxido de hidrogênio (H 2 O 2 ) em frações particuladas de tireóides suínas e humanas. Inicialmente, analisamos as propriedades bioquímicas da NADPH-oxidase - enzima geradora de H 2 O 2 - localizada na membrana apical da célula tireóidea suína. Nossos resultados demonstram que a atividade geradora de H 2 O 2 na tireóide suína ocorre, principalmente, na fração de membrana apical tireóidea (P 3.000g). Entretanto, no P 3.000g a enzima NADPH-oxidase é apenas parcialmente cálcio-dependente, ao contrário do que acontece em frações purificadas de membrana tireóidea suína, nas quais a enzima é completamente dependente de cálcio, conforme estudos anteriores. Nossos resultados confirmam os previamente descritos para a NADPH oxidase tireóidea suína. Em tecidos tireóideos humanos, a geração de H 2 O 2 ocorreu, tanto na fração microsomal (P 100.000g) quanto na fração de membrana apical (P 3.000g). Nossos dados revelam ainda que a NADPH-oxidase humana é completamente cálcio-dependente, ativada por altas concentrações de fosfato e parece ser tão ativa na glândula humana quanto na suína. Além disto, a enzima humana é dependente de adenina-flavina-dinucleotídeo (FAD) no meio de reação, ou seja, parece ser uma flavoproteína, assim como a proteína suína.

Valoración de la centelleografía con MIBI-Tc99m en el diagnóstico de cáncer tiroideo / Scanevaluation with MIBI-Tc99m as a diagnostic tool in thyroid cancer

Se valoró la captación de MIBI-TC99m en 52 pacientes que presentaron un nódulo tiroideo no funcionante demostrado en un gammagrama con yodo-131. A todos los pacientes se les administró una dosis de 370 MBq (10 mCi) de MIBI-Tc99m, adquiriendo imágenes en proyección anterior del cuello a los 5, 60 y 120 minutos después de administrado el radiofármaco y con un tiempo de adquisición para cada imagen de cinco minutos. Las imágenes se calificaron a ciegas por tres médicos especialistas en medicina nuclear de acuerdo con el siguiente criterio: negativo y positivo +, ++, +++. Los resultados centelleográficos se compararon con el sersultado histopatológico final obteniendo los siguientes datos: sensibilidad 96 por ciento especificidad 80 por ciento, valor predictivo positivo 88 por ciento y valor predictivo negativo 94 por ciento. Concluimos que el MIBI-Tc99m constituye un radiofármaco útil en caso de sospecha de cáncer tiroideo. A mayor grado de concentración del MIBI en el interior de un nódulo no funcionante, es mayor la probabilidad de cáncer de tiroides

Levothyroxine suppressive therapy is partially effective in treating patients with benign, solid thyroid nodules and multinodular goiters.

We prospectively evaluated the effect of thyrotropin (TSH)-suppressive therapy with levothyroxine (LT4) on the size of a benign, solitary, solid nodule and multinodular goiter in a relatively low iodine intake area. In this study, 101 euthyroid subjects with a benign, solitary, predominantly solid nodule (n = 54) confirmed by biopsy or multinodular goiter (n = 47) received 200 microg of levothyroxine daily as a single morning tablet for 12 months. Thirty-five receiving no therapy were considered as controls (solitary nodules, n = 20, multinodular, n = 15). Patients were admitted to the study after evaluation of thyroid biochemical parameters (thyroxine [T4], free thyroxine [FT4], triiodothyronine [T3], thyrotropin [TSH], and thyroglobulin [Tg]), thyroid scanning, ultrasound examination, and fine-needle aspiration biopsy. Every 3 months, thyroid function tests and every 6 months ultrasound examinations were repeated. Twelve months later 20 of 54 (37.1%) patients with single, solid nodules had 50% or more regression of the nodular volume (responders). Eleven of 54 (20.3%) patients had more than 20%, but less than 49.9% reduction of nodular volume (partial responders). Nonresponders were 23 of 54 (42.5%). One-third of subjects with multinodular goiter had 50% or more regression of the glandular volume, whereas 46.8% were considered as nonresponsive. The mean serum Tg levels decreased significantly only in responders with solitary nodular disease or multinodular goiter. In the control group only 1 patient (5% of total) with a solitary nodule had a 50% reduction in the nodular volume. Five others had a partial response (<49%, >20% reduction). None of the patients with multinodular goiter had a significant reduction (>50%) of the combined nodular volumes. We concluded that LT4 may be effective, among other factors, in arresting the growth or in reducing the volume of relatively small, benign, solitary, solid thyroid nodules or the combined nodular volume of multinodular goiter.

Disfunçöes tiroidianas na gravidez / Thyroid dysfunction in pregnancy

Importantes alteraçoes da funçao tiroidiana ocorrem durante o período gestacional, como as elevaçoes da globulina transportadora (TBG), do T4 e T3 totais e do T4 livre, aumento progressivo do TSH, do volume da glândula e da depuraçao de iodo pelo rim e placenta. O conhecimento destas alteraçoes é fundamental para a compreensao da fisiopatologia das disfunçoes tiroidianas, tanto na gestante como no feto. É importante salientar que algumas gestantes já se encontram previamente afetadas por disfunçao da tiróide, variando desde moderado grau de hipo ou hipertiroidismo sub-clínico, até franca tirotoxicose, ou já portadoras de nódulo na tiróide, bócio ou mesmo câncer de tiróide. Além disso, aproximadamente 5 por cento das mulheres podem também apresentar disfunçao da tiróide durante o primeiro ano após o parto. Discutem-se os aspectos fisiopatológicos, diagnósticos e terapêuticas dessa condiçoes apresentadas.