Anti-C1q autoantibodies are linked to autoimmune thyroid disorders in pregnant women.

Anti-C1q antibodies (anti-C1q) have been implicated in the pathogenesis of autoimmune diseases, including autoimmune thyroid disorders (AITD). The aim of this study was to evaluate the association between anti-C1q and thyroid function in pregnancy-associated AITD. In 96 pregnant women screened positive for AITD (thyroid dysfunction and/or antibodies against thyroperoxidase - TPOAb), anti-C1q were measured during the 9-11th gestational week and after delivery (median 16 months after delivery), and compared to the corresponding serum levels of thyroid hormones. As controls, 80 healthy pregnant women, 72 non-pregnant AITD patients and 72 blood donors were included. In the non-pregnant AITD group, two serum samples ≥ 6 months apart were analysed. Compared to blood donors, anti-C1q levels were substantially higher in all pregnant women analysed. In pregnancy, anti-C1q levels were higher in the TPOAb-positive women than in controls (37 versus 17·5%, P < 0·0001). Anti-C1q-positive pregnant women screened positive for AITD had higher thyroid-stimulating hormone (TSH) levels than anti-C1q-negative women (2·41 versus 1·94 mU/l, P = 0·01), and TSH correlated positively with anti-C1q (r = 0·226, P = 0·045) in the TPOAb-positive women. After delivery, serum levels of anti-C1q decreased in the positively screened TPOAb-negative women (8·8 versus 5·9 U/l, P = 0·002), but not in the TPOAb-positive ones, and they no longer correlated with TSH. Anti-C1q antibody levels increase during pregnancy in general and even more in the context of AITD, where they correlate with thyroid stimulating hormone levels.

Neck Muscles and Content of Carotid Artery as Reference Tissue for Strain Ratio - a Novel Approach to Improve the Diagnostic Performance of Thyroid Elastography?

Measurement of thyroid nodule stiffness by strain elastography already showed promising results. The aim of our study was to evaluate the diagnostic performance of elastography in predicting thyroid cancer by determination of strain ratio comparing nodule stiffness with thyroid tissue and surrounding neck tissues as well (carotid artery, neck muscles). Totally, 310 thyroid nodules in 275 patients were examined by conventional ultrasound and elastography prior to aspiration biopsy. 22(7.1%) thyroid carcinomas were histologically confirmed and included in the study. 39 benign nodules (27 confirmed by histology and 12 with benign cytology and at least 2 years stable ultrasound finding) formed control group. Elastography was evaluated qualitatively using 6-grade score and strain ratio to surrounding thyroid tissue, carotid artery and neck muscles was determined. High-risk elastographic score (4,5) was more frequent in carcinomas (67%) compared with benign nodules (11%, p<0.001). Significant differences in distribution of strain were found in all studied parameters except comparison with thyroid tissue in transversal dimension. Strain ratio comparing the stiffness with neck muscles had a higher negative predictive value than elastographic score and conventional ultrasound (92 vs. 83 and 82% respectively). Moreover, the combination of ultrasound and strain ratio to neck muscles increased sensitivity and negative predictive value to 100%. Our results suggest, that strain ratio to neck muscles in combination with ultrasound seems to have good sensitivity and negative predictive value for predicting thyroid cancer and may be beneficial in cases when comparison to surrounding thyroid tissue is problematic (Hashimoto thyroiditis, multinodular goiter, large nodule).

Thyroid nodules: pathophysiological insight on oncogenesis and novel diagnostic techniques.

Thyroid nodules are a very frequent pathology among common population. Despite the vast majority of them are of benign origin, the incidence of thyroid cancer is currently rather rising. Although there are several risk factors of thyroid cancer and several clinical, ultrasound, biochemical and molecular diagnostic markers, the exact mechanisms of thyroid oncogenesis and the linkage between thyroid nodule ultrasound appearance and its biological character remain unclear. While ionizing radiation is the only one well-known risk factor for thyroid cancer, the significance of some others remains unclear. The aim of our review was to discuss some not completely known pathophysiological mechanisms involved in thyroid oncogenesis as hypothyroidism, mutations of genes regulating cell proliferation, thyroid autoimmunity and pregnancy and to describe pathophysiological background of some ultrasound markers of thyroid cancer (size, echogenicity, vascularization, calcifications and stiffness). Better knowledge in this field is crucial for development of novel diagnostic techniques and therapeutic approaches. For example, the analysis of BRAF, RAS and other mutations in cytological samples may help to distinction between follicular thyroid carcinoma and follicular thyroid adenoma and may significantly decrease the number of unnecessary surgery among patients with thyroid nodules. Alternatively, the different malign cells growth, angiogenesis, destructions of thyroid follicles, reparative changes, growth retardation, fibrosis and increased interstitial fluid pressure implicate the typical ultrasound appearance of papillary thyroid cancer (hypoechogenicity, irregular vascularization, microcalcifications, stiffness) which is essential to catch the suspicious nodules on the basis of their ultrasound appearance among large amount of benign nodules.