Resumen

MARSIGLIA G, Italo. Enfermedad tiroidea asociada a otras enfermedades sistémicas. Gac Méd Caracas [online]. 2005, vol.113, n.4, pp.453-465. ISSN 0367-4762.

Thyroid hormones play a critical role in cell differentiation during development and help to maintain thermogenic and metabolic homeostasis in the adult. The T3 and T4 are essential for normal organ growth, development and function; they regulate the basal metabolic rate of all cells and thereby modulate organ and system functions. T3 and T4 act through nuclear hormone receptors to modulate gene expression. Disorders of the thyroid gland result primarily from autoimmune diseases that either stimulate the overproduction of thyroid hormones (thyrotoxicosis) or cause glandular destruction and underproduction of thyroid hormones (hypothyroidism). This review about "Thyroid disease associated with systemic diseases" is an eminently clinical view and a personal intent for etiopathogenic classification of the distinct pathological processes involved with thyroidal diseases and their dysfunction. Because frequently these associations are established between autoimmune thyroid disease (chronic autoimmune thyroiditis, silent thyroiditis and Graves´ disease) with other organ-specific and systemic autoimmune diseases, we discuss principally pathogenic mechanisms and frequency informed in the most recent medical bibliography. Additionally, this view points the association of thyroid autoimmune disease with others endocrine autoimmune processes, including polyglandular autoimmune syndrome. It is specially mentioned the influence of thyroid dysfunction over organs and systems, particularly the cardiovascular system, that are relevant in some diseases with elevated prevalence in the community, as arterial hypertension, atherosclerotic disease and dyslipidemia. However, the cardiovascular alterations of hypo or hyperthyroidism are not restricted to the forms clinically overt of thyroid dysfunction, because the minor grade dysfunction, subclinical hypothyroidism or hyperthyroidism, can also alter the cardiac function and increment cardiovascular morbimortality. Under these circumstances, it results a therapeutic imperative to restore the euthyroid state and, it is both euphemistic and equivocal the term "subclinical", for design thyroidal dysfunction that although in her minor grade, may be capable of inducing clinical manifestations in other organs with potencially devastating effects, that are illustrated in this review with a clinical case.