Autoimmune gastritis is an additional factor affecting l-T(4) requirement in patients with autoimmune thyroiditis. Serum PCA measurement should be considered in patients with an unexplained high requirement of l-T(4).

TSH-receptor (TSHR) has been found in a variety of cell types, including preadipocytes and adipocytes. In vitro, TSH-mediated preadipocyte and adipocyte responses include proliferation, differentiation, survival, and lipolysis. Objective: To measure the response of serum leptin to exogenous administration of recombinant human TSH (rhTSH) in vivo. Patients: One hundred patients with differentiated thyroid cancer already treated by total thyroidectomy and 131 I remnant ablation were enrolled. Mean (GS.E.M.) body mass index (BMI) was 26.9G0.6 kg/m 2 . Methods: Patients received a standard dose of rhTSH for measurement of thyroglobulin in the follow-up of their disease. Blood samples were taken for the assay of TSH and leptin before the first administration of rhTSH (time 0), and 24 h (time 1), 48 h (time 2), 72 h (time 3), and 96 h (time 4) after the first administration of rhTSH. Results: Significant mean serum leptin increments, with respect to basal value, were 16, 13, 18, and 11% at times 1, 2, 3, and 4 respectively. Significant positive correlations of leptin-area under the curve with respect to basal leptin levels (rZ0.43; P!0.0001) and BMI (rZ0.32; P!0.005) were observed. Conclusions: Acute rhTSH administration in hypothyroid subjects under L-thyroxine therapy produces a rise in serum leptin. This increase is proportional to the adipose mass suggesting that a functioning TSHR is expressed on the surface of adipocytes. The role that TSHR activation in adipocytes might play in physiological and pathological conditions remains a matter of investigation.

In conclusion, our study demonstrates a high, age-dependent prevalence of PCA in an unselected large population of patients with AIT.

We investigated whether serum thyroglobulin determination before surgery for differentiated thyroid carcinoma may have any prognostic value with regard to tumour extension and disease outcome in a retrospective series of 71 patients with papillary thyroid cancer. Presurgical serum thyroglobulin levels were correlated with the size of the primary tumoral nodule (p = 0.006) and of the whole thyroid (p = 0.02). The same correlation was found in a control group of patients with benign thyroid nodules, confirming that presurgical serum thyroglobulin cannot be used for the differential diagnosis of thyroid carcinoma. Presurgical serum thyroglobulin levels did not differ among patients with tumor limited to thyroid gland or extending to cervical lymph nodes or invading outside the thyroid capsule or metastasising to distant size. In addition presurgical serum thyroglobulin levels were not correlated with the disease outcome after a mean follow-up of 9 years: no difference was found among patients in complete remission or with persistent disease or dead from thyroid cancer. In conclusion, this study failed to show any prognostic value of presurgical serum thyroglobulin determination that consequently should not be measured.

Our study demonstrates that ghrelin secretion is negatively affected by autoimmune gastritis, and its serum level represents the most sensitive and specific noninvasive marker for selecting patients at high risk for ABG.