Clinical and subclinical autoimmune thyroid disorders in systemic sclerosis

Abstract

Objective: Several studies have reported the association of systemic sclerosis (SSc) with thyroid autoimmune disorders, but most of them have neither an appropriate control group nor include a complete thyroid work-up. Design: The aim of our study was to evaluate the prevalence of thyroid disorders in a large number of patients with SSc using a complete clinical evaluation. Methods: Thyroid-stimulating hormone (TSH), free triiodothyronine, free thyroxine, antithyroglobulin and antithyroid-peroxidase (AbTPO) autoantibodies, thyroid ultrasonography and blood flow and fine needle aspiration were performed in 202 SSc patients versus 404 gender-and age-matched controls from the general population, with similar iodine intake, to evaluate the prevalence of clinical and subclinical thyroid disorders. Results: Odds ratio (OR) for female SSc versus controls was: for subclinical hypothyroidism, 3.2 (95% CI)Z1.8-5.7); for clinical hypothyroidism, 14.5 (95% CIZ2.3-90.9); for AbTPO positivity, 2.7 (95% CIZ1.8-4.1); for hypoechoic pattern, 3.2 (95% CIZ2.2-4.7); for thyroid autoimmunity, 3.7 (95% CIZ2.6-5.4); for thyroid volume !6 ml, 1.8 (95% CIZ1.2-2.7). OR for thyroid autoimmunity in male SSc versus controls was 10.8 (95% CIZ2.2-52.4). Mean values of TSH in female SSc, and of AbTPO in female and male SSc were higher (P!0.01) than in controls. We observed three cases of Graves' disease in female SSc versus zero in controls (PZ0.0140), and two cases of papillary thyroid cancer in SSc patients. Conclusions: Thyroid function, AbTPO and ultrasonography should be tested as part of the clinical profile in SSc patients. Females, subjects with positive AbTPO and hypoechoic and small thyroid should have thyroid function follow-up and appropriate treatment in due course.

Polyautoimmunity and familial autoimmunity in systemic sclerosis

“…The most frequent ADs observed in patients with SSc in this study were AITD, RA, SjS, and PBC, all of which have been previously reported to be associated with SSc [11][12][13][14][15][16][17][18]. Moreover, in this study a family history of AD (FDR) was a significant predictor of polyautoimmunity.…”

Prevalence of thyroid autoantibodies in patients with systematic autoimmune rheumatic diseases. Cross-sectional study

“…According to the literature, the percentage of antithyroid antibodies in SSc ranges from 12 to 52% [36][37][38][39][40][41] and the percentage of hypothyroidism from 2.4 to 26%. 38,42 A previous study showed that presence of hypothyroidism in SSc patients was associated with higher prevalence of pulmonary hypertension. 13 It is important to highlight the high prevalence of thyroid autoimmunity in SLE and SSc cases in daily practice, since this is associated with higher prevalence of thyroid cancer.…”

Autoimmune thyroid disorders

“…CXCL10 and its receptor, CXCR3, appear to contribute to the pathogenesis of many autoimmune diseases, organ specific [such as type 1 diabetes (T1D), GD and GO], or systemic [such as systemic lupus erythematosus (SLE), MC, Sjögren's syndrome (SS), sarcoidosis, psoriasis or systemic sclerosis (SSc)] [63][64][65][66][67][68].…”

“…Thyroid function abnormalities and thyroid autoantibodies have been frequently described in patients with systemic rheumatologic autoimmune diseases, such as SS, rheumatoid arthritis (RA), SLE and SSc [67,82,83].…”