Disfunción tiroidea y trastornos del ánimo: revisión del estado del arte / Thyroid dysfunction and mood disorders: review of the state of the art

La relación entre función tiroidea y trastornos del ánimo se ha observado desde hace más de 50 años. Las hormonas tiroideas, actúan en el cerebro modulando génicamente proteínas asociadas a la fisiopatología de los trastornos del ánimo y potenciando los sistemas de neurotransmisión serotoninérgica y noradrenérgica. En el tratamiento de un episodio depresivo, la normalización de hormonas tiroideas es fundamental, y debe realizarse en todo paciente con sintomatología anímica, especialmente en aquellos con respuestas insuficientes a tratamiento, que requieren niveles de hormonas más estrictos que lo recomendado para población general. En pacientes eutiroideos, la potenciación con triyodotironina ha sido probada, pero también se ha utilizado T4 en altas dosis en casos resistentes, en que se postula que pudiese existir un estado de resistencia a hormonas tiroideas, no reflejado en los niveles hormonales periféricos evaluados rutinariamente. Las enzimas deiodasas, el receptor de hormona tiroidea, y el transportador de hormona tiroidea en la barrera hematoencefálica son blancos a investigar. Los objetivos de la presente revisión son ofrecer orientaciones respecto del uso de hormonas tiroideas en pacientes con trastornos del ánimo, una puesta al día sobre la relación entre hormonas tiroídeas y sistema nervioso central, y las interacciones entre psicofármacos y función tiroidea.

The relationship between thyroid function and mood disorders has been observed for more than 50 years. Thyroid hormones act in the brain genetically modulating proteins associated with the pathophysiology of mood disorders and potentiating the serotonergic and noradrenergic neurotransmission systems. In the treatment of a depressive episode, the normalization of thyroid hormones is essential, and should be performed in all patients with mood symptoms, especially in those with insufficient responses to treatment, which require more stringent hormone levels than recommended for the general population. In euthyroid patients, potentiation with triiodothyronine has been proven, but T4 has also been used in high doses in resistant cases, in which it is postulated that there might be a state of resistance to thyroid hormones, not reflected in the peripheral hormonal levels evaluated routinely. The enzymes deiodasas, the thyroid hormone receptor, and the thyroid hormone transporter in the blood brain barrier are white to investigate. The objectives of this review are to provide guidance regarding the use of thyroid hormones in patients with mood disorders, an update on the relationship between thyroid hormones and central nervous system, and the interactions between psychoactive drugs and thyroid function.

Recombinant human TSH versus thyroid hormone withdrawal in adjuvant therapy with radioactive iodine of patients with papillary thyroid carcinoma and clinically apparent lymph node metastases not limited to the central compartment (cN1b)

ABSTRACT Objective To compare the short- and long-term outcomes of adjuvant therapy with radioactive iodine (RAI) preceded by the administration of recombinant human TSH (rhTSH) versus thyroid hormone withdrawal (THW) in patients with papillary thyroid carcinoma and clinically apparent lymph node metastases not limited to the central neck compartment (cN1b). Subjects and methods The sample consisted of 178 cN1b patients at intermediate risk who underwent total thyroidectomy with apparently complete tumor resection [including postoperative ultrasonography (US) without anomalies] and who received adjuvant therapy with RAI (30-100 mCi) preceded by the administration of rhTSH (n = 91) or THW (n = 87). Results One year after RAI, the rates of excellent response to therapy, i.e., nonstimulated thyroglobulin (Tg) ≤ 0.2 ng/mL with negative antithyroglobulin antibodies and negative neck US, and of structural disease were similar for the two preparations (84% and 4.5%, respectively, in both groups). During follow-up (median 66 months), the rate of structural or biochemical (nonstimulated Tg > 1 ng/mL, with increment) recurrence was also similar in the two groups (4.5%). In the last assessment, the percentage of patients without evidence of disease, i.e., nonstimulated Tg < 1 ng/mL and no evidence of structural disease, was similar for the two preparations [92.3% in the rhTSH group and 97.7% in the THW group (p = 0.17)]. Conclusion Preparation with rhTSH was equally effective (short- and long-term) as THW for adjuvant RAI therapy of cN1b patients at intermediate risk and with apparently complete tumor resection.

A giant carotid aneurysm with intrasellar extension: a rare cause of panhypopituitarism

No abstract available.

Pityriasis Rubra Pilar and hypothyroidism

Pityriasis Rubra Pilaris (PRP) is a chronic and rare papulosquamous disorder. Treatment of Pityriasis Rubra Pilaris is based on empiric evidence because of several doubts regarding its etiology and also because of its relative rarity, making randomized studies difficult to perform. Some factors suggest that the metabolism of vitamin A is involved in pathogenesis. We report a case of Pityriasis Rubra Pilaris associated with autoimmune hypothyroidism which presented rapid and complete response after thyroid hormone replacement, without any association with other systemic treatment. In literature there are only three other reports of significant improvement of the lesions after hormonal correction. Deficiency of thyroid hormone inhibits the conversion of carotene into vitamin A, which would be responsible for the occurrence of Pityriasis Rubra Pilaris in this patient.

Calidad del hueso en mujeres de edad mediana con hipertiroidismo subclínico farmacológico / Bone quality in middle age women presenting with pharmacological subclinical hyperthyroidism

Las hormonas tiroideas en niveles suprafisiológicos y el hipoestrinismo son factores que pueden inducir baja masa ósea. Objetivo: determinar la calidad de hueso en mujeres en etapa de climaterio que reciben tratamiento con dosis supresivas con hormonas tiroideas. Mètodos: estudio de casos y controles realizado entre marzo de 2006 y diciembre de 2008. Incluye 113 mujeres con edades entre 40-59 años que asisten a la consulta externa de los Institutos Nacionales de Endocrinología y Oncología y Radiobiología, de ellas 43 recibían tratamiento con hormonas tiroideas (grupo estudio) y 70 no (grupo control). Mediante absorciometría dual de rayos x de columna lumbar y antebrazo, se precisó la densidad mineral ósea en g/cm² y el puntaje T, a fin de identificar la presencia de osteopenia o baja masa ósea y osteoporosis. La densidad mineral ósea de columna lumbar y antebrazo fue de 0,9229 vs. 0,8856 (p>0,05) y de 0,536 vs. 0,6226 (p<0,05) para las pacientes de los grupos de estudio y control. A mayor tiempo de tratamiento con hormonas tiroideas se encontró menor contenido mineral en ambos sitios anatómicos, aunque la afectación es mayor en antebrazo (p<0,05). El riesgo para fractura osteopenia+osteoporosis) en columna lumbar fue de 44,1 por ciento y de 50 por ciento, y en antebrazo de 44,8 y 42,7 por ciento respectivamente para las mujeres de los grupos de estudio y control (p>0,05 entre grupos). El uso de hormonas tiroideas en dosis supresiva disminuyó el contenido mineral óseo del antebrazo, sin incrementar el riesgo de fractura(AU)

Thyroid hormones at supraphysiological levels and the hypothyroidism are factors that may to induce a low bone mass. Objetive: to determine the bone quality in climacteric women under treatment with suppressive doses with thyroid hormones. Methods: the case-control study conducted between March, 2006 and December, 2008 includes 113 women aged 40-59 seen in external consultation of National Institutes of Endocrinology, Oncology and Radiobiology where 43 of them were under treatment with thyroid hormones (study group) and 70 not (control group). Using dual beam absorptiometry of lumbar spine and the forearm, it was possible to determine the bone mineral density in g/cm² and the T pointing to identify the presence of osteopenia or a low bone mass and osteoporosis. The bone mineral density of lumbar spine and forearm was of 0,9229 vs. 0,8856 (p<0,05) and of 0,536 vs. 0,6226 (p<0,05) for patients of study group. With treatment using thyroid hormones there was less mineral content in both anatomical sites, although the involvement if greater in the forearm (p<0,05). Fracture risk (osteopenia+osteoporosis) in lumbar spine was of 44,1 percent and of 50 percent and in the forearm was of 44,8 and 42,7 percent, respectively for women from both groups. The use of thyroid hormones in suppressive doses decreased the bone mineral content in forearm with no increase of facture risk(AU)

Ovarian tumors with elevated ca-125 levels and severe juvenile hypothyroidism: A need for increased awareness.

A 15-yr-old girl presented with bilateral gross ovarian tumors, clinical features of long-standing unrecognized hypothyroidism and markedly elevated CA-125 levels. Ovarian resection was avoided, as the presentation was consistent with the Van Wyk and Grumbach syndrome; and the patient was treated with replacement of thyroid hormone. Regression of the ovarian tumors occurred 6 months after initiation of the treatment. The authors emphasise the need for increased awareness and screening for hypothyroidism in patients with ovarian tumors, in order to prevent inadvertent operative interventions.

Infertilidad femenina, mejora luego del diagnóstico y tratamiento del hipotiroidismo subclínico / Female infertility, improves after of the diagnosis and tratment of subclinic hypothyroidism

Introducción: El hipotiroidismo subclínico se conoce desde 1970, cursa a menudo en forma asintomática o con signos clínicos indefinidos, de los cuales, la falla reproductiva es uno de ellos. Y su prevalencia en la literatura es muy variable. Material y métodos: Se realizó un estudio prospectivo, apareado, directo, no ciego, no experimental, de 59 mujeres en edad reproductiva, que por un año buscaron embarazo sin conseguirlo, en las que se descartó otras causas de falla reproductiva, tiempo que fue desde marzo del año 2000 hasta diciembre de 2005. Se les busco sistemáticamente hipotiroidismo subclínico y posteriormente se les inició tratamiento con hormona tiroidea, observándolas por un periodo de un año, registrándose si se obtenía o no una gestación. Resultados: en nuestro grupo de estudio de las 59 mujeres incluídas, al cabo de un año de iniciado el tratamiento con hormona tiroidea se consiguió gestación en 15 de ellas (el 25.42 por ciento). Al analizar dicho resultado mediante metodología estadística, para nuestra apareada, se obtuvo una diferencia estadísticamente significativa, dando una p=0.0001093. Conclusiones: consideramos que el hipotiroidismo subclínico debe ser buscado rutinariamente en personas que buscan fertilidad y no tienen otra causa de falla reproductiva que impida conseguir el embarazo. Los resultados obtenidos con tratamiento hormonal tiroideo adecuado, en este pequeño grupo de pacientes, logró conseguir el 25.42 por ciento de gestaciones. Situación que abre la posibilidad de ampliar ésta actitud a un grupo mayor de pacientes en un contexto semejante.

Hipotiroidismo severo y bipolaridad: a propósito de un caso clínico / Severe hypothyroidism and bipolarity: a clinical case

The description of a clinical case of a woman with a background of bipolar disease which during an episode cataloged as depression was found to have a thyroid laboratory profile compatible with hypothyroidism and that improves with the administration of the thyroid hormone. Her evolution is compatible with the presence of rapid cycling and mixed states. Based on revisions of literature we can highlight the strait ties between both pathologies. We propose hypothesis relating the bipolar syndrome and the alterations in the axe hypothesis- hypothalamus-thyroid in the transversal and longitudinal aspects.

Se describe el caso clínico de una mujer con antecedentes de enfermedad bipolar que durante un episodio catalogado como depresivo se encontró un perfil tiroideo de laboratorio compatible con hipotiroidismo y que mejora con la administración de hormona tiroidea. Su evolución es compatible con la presencia de ciclación rápida y estados mixtos. En base a revisión de la literatura se destaca el estrecho vínculo entre ambas patologías. Se plantean hipótesis para relacionar los trastornos bipolares con alteraciones del eje hipófisis-hipotalámico-tiroides en sus aspectos transversales y longitudinales.

Hipotireoidismo: como eu trato? / How do I treat?

O hipotireoidismo resulta de uma menor produção ou ação dos hormônios tireoidianos, levando a uma lentidão generalizada dos processos metabólicos. Pode ocorrer em qualquer idade, acometendo desde o recém-nascido até idosos. O tratamento do hipotireoidismo clínico ou manifesto é consenso absoluto; controvérsias permanecem, entretanto, quanto à necessidade do tratamento de pacientes com hipotireoidismo subclínico. Nestes casos, existe indicação mais consistente, ainda que não formal, de tratamento em pacientes com tireotrofina (TSH) acima de 10mUI/L, em especial se associada à presença de anticorpos antitireoidianos, bócio, dislipidemis ou sintomas de hipotireoidismo.

Hypothyroidism is the result of insufficient production or action of the thyroid hormone causing the speed reduction of the metabolic processes. It may occur at all ages affecting from newborns to elderly. Treatment of clinical hypothyroidism is absolute consensus; however controversy remains about the need for treating patients with subclinical hypothyroidism. In these cases, there is a more consistent treatment indication, even though not formal, in patients with the presence of thyroid antibodies, goiter, dyslipidemia or hypothyroidism symptoms.

Primary hypothyroidism with pericardial tamponade.

We report a rare case of pericardial effusion and tamponade in a 10-yr-old child with undiagnosed primary hypothyroidism, who presented to us with delayed milestones, anasarca for 7 mth and respiratory distress for 20 days. The child recovered with ultrasound guided pericardial tap and thyroxine replacement therapy.

Hipotiroidismo neonatal: fisiopatogenia, aspectos moleculares, metabólicos y clínicos / Neonatal hypothyroidism: Pathophysiogenic, molecular and clinical aspects

This review provides an updated summary on both the clinical and diagnostic aspects of neonatal hypothyroidism (NeH); as well as on the molecular and pathophysiologic processes known to be involved in the installment of this important hormonal deficiency. Current information regarding its etiology and pathogenesis has allowed classigying NeH in three major groups: endemic, transient, and sporadic hypothyroidism. The later corresponds to congenital hypothyroidism and encompasses a broad spectrum of hereditary disorders causing hypothyroidism in newborns and young children. These congenital disorders include hypothalamic-pituitary or thyroid dysgenesis and/or dyshormonogenesis, as well as hyporesponsiveness or resistance to either TRH, TSH or to thyroid hormones. The introduction of national screening programs for NeH have overcome the difficulties in the early diagnosis thus helping to prevent its serious and irreversible consequences on intellectual and physical development. Concomitantly, an increase in the need for complementary etiologic and molecular diagnosis has risen. The current capability to perform a fine and precise diagnose is crucial both for treatment of the affected infant and for genetic counseling of the family. Although incomplete, available epidemiological information in Mexico indicates that NeH prevalence can be as high as twice that in other developed world countries. On these bases, national public health policies and epidemiological surveyance must be strengthen not only to identify, diagnose and timely treat, but to prevent and eradicate endemic NeH.

Este trabajo revisa algunos aspectos del conocimiento actual sobre la fisiopatogenia, los hallazgos clínicos y el diagnóstico bioquímico y molecular del hipotiroidismo neonatal (HNe). El término HNe denota un conjunto de entidades clínicamente pleomórficas, que invariablemente cursan con una disminución en el aporte; o bien, en la disponibilidad celular y/o en la respuesta a las hormonas tiroideas (HT) durante la etapa perinatal. Las HT o yodotironinas son indispensables para la morfogénesis y maduración funcional normal de prácticamente todos los tejidos en el organismo, y su participación es crucial en el caso del sistema nervioso. La información actual permite realizar una clasificación del HNe tanto en términos etio y fisiopatogénicos, como en el contexto del substrato genético que los determina. Así, se reconocen tres grandes tipos de HNe: el endémico, el transitorio y el esporádico. Este último grupo de HNe incluye los defectos hipotálamo-hipofisiarios, los trastornos ontogenéticos o disgenesias tiroideas, la resistencia periférica a las HT y las dishormonogénesis. Por otra parte, en la comunidad internacional existe una creciente preocupación por la contaminación ambiental debida a órgano-halógenos antropogénicos. Estos compuestos han mostrado su potencial como agentes distiroideos en animales de experimentación y en algunos estudios clínicos. En México, tanto la distribución geográfica y prevalencia del HNe, como la deficiencia de yodo y otros micronutrimentos en la dieta, se han analizado de manera esporádica y no sistemática. Aunque incompleta, la información disponible sugiere que en nuestro país la prevalencia de HNe es sensiblemente mayor que la reportada mundialmente. Contar con información completa y confiable acerca de estos aspectos no es trivial, puesto que su conocimiento permitirá establecer políticas razonadas de salud pública para identificar, diagnosticar y tratar oportunamente el padecimiento; así como para prevenir y erradicar el HNe endémico.

Depressão resistente a tratamento: uma revisão das estratégias farmacológicas de potencialização de antidepressivos / Treatment-resistant depression: review of pharmacologic antidepressant strategies

OBJETIVO: Fazer uma revisão sobre oito estratégias farmacológicas de potencialização de antidepressivos na DRT. MÉTODOS: Fez-se um levantamento bibliográfico de 1990 até janeiro de 2006, nas bases eletrônicas de busca Medline, LILACS e da Biblioteca Cochrane, utilizando-se os termos de busca treatment, resistant, refractory e depression e os descritores depression, drug resistance e augmentation, incluindo apenas ensaios controlados duplo-cegos. Foi consultada a referência dos artigos para obtenção de ensaios realizados em data anterior a 1990 e artigos originais de valor histórico. RESULTADOS: Foram encontrados 17 estudos duplo-cegos com o lítio, seis com o hormônio tireoidiano, dois com a buspirona, seis com o pindolol, um com a carbamazepina, dois com a lamotrigina e quatro com a olanzapina. Foram favoráveis à potencialização 41,2 por cento dos ensaios com lítio; 60 por cento daqueles com hormônio tireoidiano e antidepressivos tricíclicos e nenhum com hormônio tireoidiano e inibidores seletivos da recaptação da serotonina (ISRS); 50 por cento dos com pindolol; 100 por cento dos ensaios com carbamazepina e 40 por cento daqueles com olanzapina. Nenhum dos estudos com a buspirona foi favorável. No único estudo com lamotrigina não houve eficácia de tratamento na avaliação pelo critério principal, mas superioridade ao placebo em critérios secundários. CONCLUSÃO: Na DRT há evidência de eficácia apenas em relação ao lítio na potencialização de várias classes de antidepressivos e ao hormônio tireoidiano na potencialização de tricíclicos. A olanzapina foi razoavelmente estudada e sua eficácia não foi estabelecida. Os poucos estudos realizados com a buspirona e o pindolol não comprovaram sua eficácia. A carbamazepina foi muito pouco estudada, e a lamotrigina ainda não foi adequadamente avaliada.

OBJECTIVE: The aim of this study is to review eight pharmacologic antidepressant augmentation strategies in TRD. METHODS: Database search on Medline, LILACS and Cochrane Library, from 1990 to June 2006 using the words treatment, resistant, refractory, depression and the medical subject headings depression, drug resistance and augmentation. Double-blind controlled trials and reviews were included. We also consulted reference of the articles in order to obtain studies and original articles of historical value from before 1990. RESULTS: There were 17 double-blind trials with lithium, six with thyroid hormone, two with buspirone, six with pindolol one with carbamazepine, two with lamotrigine and four with olanzapine. Forty-one percent of the trials with lithium, 60 percent of those with thyroid hormone and tricyclics, 0 percent of the ones with thyroid hormone and selective serotonin reuptake inhibitors (SSRI), 50 percent of those with pindolol, 100 percent of those with carbamazepine and 40 percent of the ones with olanzapine were favorable. No trials with buspirone were favorable. The only trial with lamotrigine did not show efficacy using the main outcome measures. Otherwise, there was superiority over placebo on secondary measures. CONCLUSION: Only lithium and thyroid hormone showed efficacy as antidepressant augmentation strategies for TRD. Olanzapine was reasonably studied and did not prove its efficacy. There were just a few studies on buspirone and pindolol and they were not favorable to them. Carbamazepine was studied very little. Lamotrigine was not adequately evaluated.

Influência do hipotireoidismo subclínico em pacientes com hipercolesterolemia / Influence of subclinical hypothyreoidism in patients with hypercholesterolemia

O hipotireoidismo subclínico primário é uma causa importante de hipercolesterolemia. Devido à alta incidência de dislipidemia na população atual, este estudo investiga a função tireoideana em pacientes clinicamente eutireoideos e que apresentam dificuldades em controlar o colesterol. Foram realizados exames de função da tireóide em 30 pacientes sem evidências clínicas de hipotireoidismo e com dislipidemia refratária a tratamento convencional. Estes pacientes apresentavam média de TSH de 10,53UI/mL, T4 livre de 0,63ng/dL, colesterol total de 269,17mg/dL, HDL de 34,03mg/dL e LDL de 181,70mg/dL. Após 3 meses de terapêutica com levotiroxina sódica na dose de 100 a 150 microgramas diários, as médias obtidas foram: TSH 1,93UI/mL, T4 livre 1,18ng/dL, colesterol total 201,77mg/dL, HDL 45,8mg/dL e LDL 125,1mg/dL, evidenciando significativa melhora no perfil lipídico destes indivíduos. Nossos resultados indicam que os pacientes com hipercolesterolemia secundária a hipoteireoidismo subclínico foram beneficiados com o tratamento da disfunção tireoideana.

Subclinical hypothyroidism is an important cause of hypercholesterolemia. Owing to the high incidence of dyslipidemia, this study investigates thyroid profile of patientsapparently euthyroid with disorders in the cholesterol metabolism. Thyroid function exams were performed on 30 patients with no clinical evidence of hypothyroidism who had failed ondislipidemic conventional therapy. These patients had the following average levels: TSH 10,53 mUI/mL, free T4 0,63ng/dL, total cholesterol 269,17 mg/dL, HDL 34,03 mg/dL and LDL 181,70 mg/dL. After 3 months of treatment with sodic levothyroxine, 100-150 micrograms/day, the average ranges were: TSH 1,93 mUI/mL, free T4 1,18 ng/dL, total cholesterol 201,77 mg/dL,HDL 45,8 mg/dL and LDL 125,1 mg/dL. It shows an improvement in the lipid profile. Our results indicate that patients with hypercholesterolemia caused by subclinical hypothyroidism were benefited by thyroid disfunction treatment.

Tiroides lingual. Reporte de dos casos / Lingual thyroid. Report of two cases

La glándula tiroides cumple una importante función en el organismo debido a la participación de sus hormonal en el crecimeinto, maduración y funcionamiento normal de las células y tejidos. Durante la embriogénesis, el tubérculo tiroideo debe migrar caudalmente para permitir la fusión de las prominencias laterales de la lengua, y cuando ello no ocure, queda atrapado en la base de la lengua. Se informan dos casos de niñas de 4 y 11 años de edad quienes presentaron una masa en el tercio posterior de la lengua diagnosticada como tiroides lingual, casos que fueron confirmados mediante gamagrafía de tiroides

Myoglobinuria and transient acute renal failure in a patient revealing hypothyroidism.

Muscle involvement in hypothyroidism commonly manifests as fatigue, myalgias, stiffness and slowed reflexes. We report a case of transient acute renal failure related to rhabdomyolysis and myoglobinuria in a 40 year old man that revealed the diagnosis of hypothyroidism with myopathy. The patient had proximal muscle weakness and tenderness, markedly raised muscle enzymes and deranged renal functions that normalised with thyroid replacement therapy. Hypothyroidism, though rare, should be considered a definite and authentic cause of rhabdomyolysis.

Bocio difuso eutiroideo: respuesta al tratamiento con hormonas tiroideas durante 15 años / Euthyroid diffuse goitre. Response to the treatment with thyroid hormones during 15 years

Se realizó un estudio descriptivo y retrospectivo de 107 pacientes con bocio difuso eutiroideo para evaluar los resultados del tratamiento con hormonas tiroideas. Según disminuyó o no el tamaño del bocio se definieron las categorías de respuesta: satisfactoria y no satisfactoria. Se realizaron cortes evaluativos al año, a los 5, 10 y 15 años. Como variables predictoras de la respuesta empleamos: edad, peso inicial de la glándula, antecedentes familiares de tiroidopatías, tiempo de evolución del bocio y dosis de hormonas empleadas. Se aplicaron las pruebas de chi cuadrado y de regresión logística. Se recogieron además las reacciones adversas referidas y la posible asociación con la dosis. Durante el período evaluado, el bocio disminuyó aproximadamente 8 g de 39,74 a 31,35 g como promedio y sólo fue significativo en el primer año de tratamiento (p < 0,001). El riesgo relativo para desarrollar una respuesta no satisfactoria: al año fue, 3 veces mayor cuando el tiempo de evolución referido del bocio era mayor de 1 año y 64 porciento menor cuando se empleó dosis supresiva; a los 5 años, 5 veces mayor cuando el tiempo de evolución era mayor de 1 año; a los 10 años fue 4 y 3 veces mayor cuando el tiempo de evolución fue mayor de 1 año y la edad, superior a los 30, respectivamente; a los 15 años ninguna variable predijo la respuesta. El nerviosismo, la disminución de peso y la sudación fueron los síntomas más frecuentes y se relacionaron con el empleo de dosis supresivas en los primeros 5 años (p < 0,01). Se concluyó que el tiempo máximo para evaluar la respuesta osciló entre 1 y 2 años y que los bocios de poco tiempo de evolución y de causa autoinmune, constituyeron signos de buen pronóstico