Autoimmune thyroiditis

Carayanniotis, G., The cryptic self in thyroid autoimmunity The paradigm of thyroglobulin, Autoimmunity, 36, 423, 2003. 

Hashimoto s thyroiditis Autoimmune destruction of thyroid Present early, absent later Mild to severe... 

The complexity of the interaction between iodine intake and autoimmune thyroid disease has been highlighted by reports of evidence that iodide (compared with thyroxine) induces thyroid autoimmunity in patients with endemic (iodine deficient) goiter (43), while in those with pre-existing thyroid autoimmunity, evidenced by the presence of antithyroid (thyroid peroxidase) antibodies, administration of iodine in an area of mild iodine deficiency led to subclinical or overt hypothyroidism (44). 

Kahaly GJ, Dienes HP, Beyer J, Hommel G. Iodine induces thyroid autoimmunity in patients with endemic goitre a randomised, double-blind, placebo-controlled trial. Eur J Endocrinol 1998 139(3) 290-7. 

The risk of amiodarone-induced hypothyroidism may be greater in patients who have pre-existing thyroid autoimmune disease (76). There is some evidence that the risk of hypothyroidism due to amiodarone is increased in elderly patients (77), but the data are not conclusive. 

Hypothyroidism occurs more often than hyperthyroidism, and spontaneous resolution is expected in almost 60% of patients with or without interferon alfa withdrawal. Finally, female sex and the presence of baseline thyroid autoimmunity were confirmed to be the most significant risk factors. The mechanisms of interferon alfa-induced thyroid dysfunction are not yet fully clarified. Although an autoimmune reaction or immune dys-regulation are the most likely mechanisms, a direct inhibitory effect of interferon alfa on thyrocytes should be considered in patients without thyroid antibodies. 

Possible mechanisms need to be clarified. Since thyroid autoantibodies are detected in most patients who develop thyroid disorders, the induction or exacerbation of preexisting latent thyroid autoimmunity is the most attractive hypothesis. This is in accordance with the relatively frequent occurrence of other autoantibodies or clinical autoimmune disorders in patients who develop thyroid disorders (514). However, 20-30% of patients who develop thyroid diseases have no thyroid antibodies, and it is thus not yet proven that autoimmunity is the universal or primary mechanism. In fact, there were subtle and reversible defects in the intrathyroidal organification of... 

The occurrence of thyroid dysfunction in 72 patients treated with interferon alfa plus ribavirin (1.0-1.2 g/day) has been compared with that of 75 age- and sex-matched patients treated with interferon alfa alone for chronic hepatitis C (523). Of the former, 42 patients, and of the latter, 40 patients had received previous treatment with interferon alfa alone. There was no difference in the rate of thyroid autoimmunity (antithyroglobulin, antithyroid peroxidase, and thyroid-stimulating hormone receptor... 

Autoimmune polyglandular syndrome with progressive thyroid autoimmunity, type 1 diabetes mellitus, amenorrhea, and adrenal insufficiency has been reported in a 51-year-old woman treated with interferon alfa for chronic hepatitis C (545). Pancreas and pituitary gland autoantibodies, which were undetectable before interferon alfa treatment, were present at the time of diagnosis. After withdrawal, she recovered normal thyroid function, but was still insulin dependent with amenorrhea and adrenal insufficiency. 

In 106 patients (76 women) with multiple sclerosis who received interferon beta-la or beta-lb for up to 84 (median 42) months, there was baseline thyroid autoimmunity in 8.5% and hypothyroidism in 2.8% (562). Thyroid dysfunction (80% hypothyroidism, 92% subclinical, 56% transient) developed in 24% (68% with autoimmunity) and autoimmunity in 23% (46% with dysfunction), without a significant difference between the two cytokines 68% of the cases of dysfunction occurred within the first year. Thyroid dysfunction was generally subclinical and was transient in over half of cases. Autoimmunity was the only predictive factor for the development of dysfunction (relative risk = 8.9), but sustained disease was also significantly associated with male sex. 

Martino E, Aghini-Lombardi F, Bartalena L, Grasso L, Loviselli A, Velluzzi F, Pinchera A, Braverman LE. Enhanced susceptibility to amiodarone-induced hypothyroidism in patients with thyroid autoimmune disease. Arch Intern Med 1994 154(23) 2722-6. 

Amato G. Long-term outcome of interferon-alpha-induced thyroid autoimmunity and prognostic influence of thyroid autoantibody pattern at the end of treatment. J Clin Endocrinol Metab 2001 86(5) 1925-9. 

Monzani F, Caraccio N, Dardano A, Ferrannini E. Thyroid autoimmunity and dysfunction associated with type I interferon therapy. Clin Exp Med 2004 3 199-210. 

Marazuela M, Garcia-Buey L, Gonzalez-Fernandez B, Garcia-Monzon C, Arranz A, Borque MJ, Moreno-Otero R. Thyroid autoimmune disorders in patients with chronic hepatitis C before and during interferon-alpha 527. therapy. Clin Endocrinol (Oxf) 1996 44(6) 635-42. 

Pagliacci MC, Pehcci G, Schippa M, Liberati AM, Nicoletti I. Does interferon-beta therapy induce thyroid autoimmune phenomena Horm Metab Res 1991 23(4) 196-7. 

Martinelli V, Gironi M, Rodegher M, Martino G, Comi G. Occurrence of thyroid autoimmunity in relapsing remitting multiple sclerosis patients undergoing interferon-beta treatment. Ital J Neurol Sci 1998 19(2) 65-7. 

Rotondi M, Oliviero A, Profice P, Mone CM, Biondi B, Del Buono A, Mazziotti G, Sinisi AM, Bellastella A, Carella C. Occurrence of thyroid autoimmunity and dysfunction throughout a nine-month follow-up in patients undergoing interferon-beta therapy for multiple sclerosis. J Endocrinol Invest 1998 21(ll) 748-52. 

Ban Y, Tomer Y. Genetic susceptibility in thyroid autoimmunity. Pediatr Endocrinol Rev. 2005 3 ... 

Autoimmune diseases have been reported to be more frequent in human subjects treated with several recombinant cytokines [38], For instance, increased titers or the new occurrence of autoantibodies have been observed in hepatitis C patients treated with the recombinant interferons-alpha (IFNa). Quite a few clinical case reports describe the development of organ-specific as well as systemic autoimmune diseases including systemic lupus erythematosus, insulin-dependent type I diabetes mellitus, autoimmune thrombocytopenia, autoimmune hemolytic anemia, myasthenia gravis, and autoimmune thyroiditis in patients under IFNa therapy. Although the mechanism involved is not fully elucidated, the available data support the pathogenic potential of IFNa in autoimmunity [31]. In contrast, autoimmune effects associated with IFNp therapy are thought to be of lesser concern based on the current clinical evidence [38], Thyroid autoimmunity in contrast to other autoimmune diseases is frequent in patients treated with recombinant interleukin-2 (rIL-2). Thus, among 281 previously euthyroid cancer patients treated with rIL-2, up to 41%... 

In a controlled, cross-sectional comparison of 100 patients with mood disturbance who had taken lithium for at least 6 months and 100 psychiatrically normal controls, lithium did not increase the prevalence of thyroid autoimmunity a minimally larger number of control subjects had antithyroid peroxidase antibodies (11 controls versus 7 patients with mood disorders) and anti-thyroglo-bulin antibodies (15 versus 8) (259). 

H2O2-generating system which may be an NADPH (NADH) oxidase system similar to that of leukocytes (Chapter 15). Thyroperoxidase is a glycosylated heme enzyme that is bound to the apical plasma membrane of the thyrocyte. Thyroperoxidase exists in two molecular forms (M.W. 105,000 and 110,000) and its catalytic domain faces the colloid space. In thyroid autoimmune disorders, one of the major microsomal antigenic components is thyroperoxidase. 

Hashimoto thyroiditis. Goitrous form of diffuse autoimmune thyroiditis. See also thyroiditis, autoimmune. 

Hypothyroidism. Hypofunction (insufficiency) of the thyroid gland. Autoimmunity is the most common cause of hypothyroidism in iodine-sufficient countries. See also thyroiditis, autoimmune Hashimoto thyroiditis primary myxoedema. 

Sjogren syndrome. Chronic inflammatory autoimmune disease of the exocrine glands of unknown etiology. Its primary symptoms are keratoconjunctivitis sicca and xerostomia. Two types of Sjogren syndrome are distinguished a primary (isolated) type and a secondary type associated with another underlying autoimmune disease (e.g. rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, primary biliary cirrhosis, autoimmune hepatitis, multiple sclerosis, thyroiditis, autoimmune, etc.). Ro/SS-A and La/SS-B autoantibodies are used as classification criteria. 

Spontaneous autoimmune thyroiditis (SAT). Autoimmune thyroiditis ( - thyroiditis, autoimmune) that develops spontaneously (without any apparent cause or manipulation) in certain strains of mice and rats (e.g. NOD mice, BB and BUF rats) as well as in other animals (e.g. OS chickens, marmoset monkeys, beagles). 

Thyroglobulin (TG). This glycoprotein secreted by thyroid follicular cells is a major autoantigen in autoimmune thyroid diseases. Thyroglobulin autoantibodies were found in patients with autoimmune thyroiditis ( - thyroiditis, autoimmune) and Graves disease. 

Thyroiditis, autoimmune. Inflammatory destruction of the thyroid gland (ranging from a mild focal thyroiditis to extensive... 

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