No abstract

No abstract

The localization and biological roles of the multifunctional cell type mast cells remain unclear in subacute thyroiditis that is characterized by both epithelioid granuloma formation and thyroid tissue repair. We examined their immunolocalization with tryptase of a mast cell marker, using the biopsy specimens from 12 cases. In the epithelioid granuloma, no mast cells were detected in any of the cases, although a small number of them (4.6 +/- 2.4) were seen at the fibrous stroma around the granuloma in all cases. By contrast, in all cases, increased mast cells (28 +/- 7.2) localized at the thyroid tissue-regenerative site where both thyroid folliculogenesis and angiogenesis take place. To elucidate possible roles of mast cells in the disease, we also examined their immunoexpressions of vascular endothelial cell growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived growth factor-BB (PDGF), transforming growth factor-beta1 (TGF-beta1) and epidermal growth factor (EGF), which affect thyroid folliculogenesis and angiogenesis. In all 12 cases, mast cells displayed all of these growth factors in a manner not specific to the infiltrating site. The data suggest that growth factor-expressing mast cells may play crucial roles in the thyroid tissue repair of subacute thyroiditis, modulating thyroid folliculogenesis and angiogenesis; and that the multifunctionality of the cells may be partly dependent on their expressions of various growth factors.

We studied the utility of color Doppler ultrasonography in patients with subacute thyroiditis. Eighteen patients with subacute thyroiditis (SAT) with painful goiter and thyrotoxicosis underwent color Doppler ultrasonography during the acute and recovery stages of the disease. Thyroid vascularization in these patients was compared with that of 15 untreated patients with Graves' disease and 17 control subjects. During the acute stage of subacute thyroiditis, color Doppler ultrasonography showed low echogenicity without increased tissue vascularity in the affected swollen thyroid. In the recovery stage, color Doppler ultrasonography showed isoechogenicity with slightly increased vascularization. Vascularization became normal at 1 year follow-up time. In contrast, marked by increased vascularization was observed in patients with untreated Graves' disease. Color Doppler ultrasonography showed clear differences between SAT and Graves' disease patients. Vascularity was significantly correlated with serum free thyroxine (FT4) and thyrotropin (TSH) concentrations in the recovery stage (3 months after the initial ultrasonography). Color Doppler ultrasonography accurately visualized lesions without increased vascularity in the acute stage of SAT and lesions of slightly increased vascularity in the recovery stage. Color Doppler ultrasonography may be a useful, noninvasive, and rapid method for differentiating SAT from Graves' disease and for evaluating and monitoring the location and activity of lesions in SAT.

No abstract