TSH secretion is controlled by the stimulatory action of hypothalamic TRH and the inhibition via central dopaminergic and somatostatinergic mechanisms as well as by a hypothalamic inhibitory action of thyroid hormones. Metoclopramide is DA2 receptor blockade which can accelerate to elevate the concentration of serum TSH in hypothyroidism, which is accompanied by a progressive loss of dopaminergic tone as demonstrated by a progressive increase in prolaction serum levels, especially in patients with differentiated thyroid carcinoma(DTC). So the period of L-thyroxine withdrawal is contracted and the symptoms of hypothyroidism is released. It's important to monitor and treat DTC patients with radioactive iodide.
Dopamine Antagonists ; pharmacology ; Humans ; Hyperthyroidism ; blood ; drug therapy ; Hypothalamo-Hypophyseal System ; drug effects ; physiology ; Hypothyroidism ; blood ; drug therapy ; Metoclopramide ; chemistry ; pharmacology ; Thyroid Gland ; drug effects ; physiology ; Thyroid Hormones ; blood ; Thyrotropin ; blood

This paper is aimed to evaluatethe thyroglobulin autoantibody (TgAb) interference in measurement of thyroglobulin (Tg) between electrochemiluminescent assay (ECLIA) and radioimmunoassay (RIA). Tg and TgAb of 84 sera, including 22 Graves' hyperthyroidism(GD), 24 Hashimoto thyroiditis (HT) and 38 differentiated thyroid carcinomas (DTC), were measured by RIA and ECLIA, respectively. Recovery tests were carried out in 3 groups. The sera samples of the first group were added 3 different amount of Tg calibrator; the sera samples of the second group were diluted 5 times, then 100 ng/ml Tg calibrator was added; the sera samples of the third group were divided into different subgroups depending on TgAb concentration with adding 100 ng/ml Tg calibrator,Tg and TgAb were measured in each dilution by ECLIA and RIA. Recovery rate was calculated. The Tg and TgAb values measured by ECLIA were correlated with that measured by RIA (r = 0.676, P = 0.000; r = 0.677, P = 0.000, respectively). When TgAb concentration increased, the Tg values decreased by ECLIA and increased by RIA. The TgAb values were decreased when sera were diluted, and the Tg values also reduced by RIA and increased by ECLIA. The added different amount of Tg calibrator had not significant influence on Tg recovery rates. When TgAb concentration increased, recovery rates of Tg were decreased by ECLIA and increased by RIA. When sera were diluted, the recovery rates of Tg were increased by ECLIA while decreased by RIA. RIA and ECLIA have good correlation with Tg measurement in 10-400 ng/ml. ECLIA has wider measuring range and higher sensitivity than RIA. RIA and ECLIA have good correlation with TgAb measurement. When TgAb is positive, Tg values are underestimated by ECLIA and overestimated by RIA. When sera are diluted, Tg value and the recovery rate are increasing by ECLIA and decreased by RIA. Recovery test can not efficiently rectify Tg value when TgAb is positive.
Adolescent ; Adult ; Aged ; Autoantibodies ; blood ; Child ; Electrochemical Techniques ; Female ; Graves Disease ; blood ; Hashimoto Disease ; blood ; Humans ; Luminescent Measurements ; methods ; Male ; Middle Aged ; Radioimmunoassay ; methods ; Thyroglobulin ; blood ; immunology ; Thyroid Neoplasms ; blood ; Young Adult

Objective To evaluate the effect of 131 iodine(131I) therapy in medium and large goiter with hyperthyroidism in order to investigate the influence of pretreatment with antithyroid drugs (ATD) methimazole(MMI) and propylthiouracide (PTU) on 131I therapy.Methods A total of 338 hyperthyroidism patients (136 cases for male,202 cases for female) with thyroid mass greater than 40 grams were treated with 131I in the People's Hospital of Sichuan Province.Thyroid function,thyroid 131I uptake ratio and thyroid imaging were measured before treatment were measured 1-3 months later after administration of 131I,and they were followed up for 6 months to 4 years.Results There were statistical difference between pretreatment and 3 months later of 131I therapy in terms of free triiodothyronine (FT3),(Free thyroxine) FT4.The level of FT3 decreased from (31.9 ± 16.2) pmol/L to (7.8 ±8.5) pmol/L(t =23.9,P =0.000) and level of FT4 decreased from (58.8 ± 22.2) pmol/L to (19.4 ± 16.9) pmol/L(t =25.4,P =0.000).Among 338 patients,109 patients (32.2％) were developed hypothyroidism,and 91 patients (26.9％) were cured,91patients (26.9％) with improved state,20 patients(5.9％) with ineffective and 27 patients(8.0％) with relapse after administration of 131I.The total effective rate was 94.1％ (318/338).Thyroid weight,levels of FT3,FT4,thyroglobulin antibody(TGA),thyroid microsomal antibody(MCA) in effective group were (49.8 ± 9.97) g,(32.5 ± 16.3) pmol/L,(59.5 ± 22.2) pmol/L,(43.6 ± 35.3) ％,(30.1 ± 22.6) ％ respectively,and were (56.9±15.7) g,(22.8 ± 12.8) pmol/L,(47.9 ±20.3) pmol/L,(22.8±30.0)％,(15.3 ±20.5)％ respectively in ineffective group.There were statistically significant differences between the ineffective group and effective group (t =2.932,2.602,2.287,2.501,2.766 ; P =0.000,0.010,0.023,0.013,0.006).Logistic regression analysis was showed that weight of thyroid and serum FT3 were the most important factors in affecting 1131 therapy.Conclusion 131 I therapy for medium and large-sized goiter with hyperthyroidism is safe and effective.ATD may not reduce the effectiveness of subsequent 131I of hyperthyroidism.Thyroid weight and FT3 are the key influential factors in affecting 131I.

Serum thyroglobulin (Tg) is primarily used as a tumor marker to detect the recurrent or persistent disease in patients with differentiated thyroid carcinomas. Unfortunately, the serum Tg measurement is technically challenging and the thyroglobulin autoantibody (TgAb) interference remain the most serious problem limiting the clinical value of serum Tg. The direction and magnitude of the interference are related to the method and the concentration and affinity of the TgAb in the specimen. The objective of this study was to evaluate TgAb's interference with assay of Tg by electrochemiluminescent assay (ECLIA). The Tg and TgAb of 84 sera were measured by the ECLIA. Recovery tests were carried out in 3 groups. 3 different Tg calibrators, 50, 100, 200 ng/ml, respectively, were added into the sera of the first group. The sera of second group were doubly diluted 5 times, and meawhile the Tg and TgAb were measured after each dilution, and then 100 ng/ml Tg calibrator was added into the sera. The sera of third group were divided into different subgroups according to TgAb concentration and then 100 ng/ml Tg calibrators were added. Recovery rate (%) was calculated. Tg value decreased when TgAb concentration increased by ECLIA, TgAb value became lower when sera were diluted, Tg value increased. The added Tg calibrator had not significant influence on Tg value and Recovery rate. Recovery rate was lower when TgAb concentration increased. When sera were diluted, the recovery rate was increased. Tg value were underestimated by TgAb interference. After sera were diluted, Tg value became increasing by ECLIA. The added Tg calibrator had not significantly influence on Tg value and Recovery rate. When sera were diluted, the recovery rate was increased. TgAb concentration had significant influence on Recovery rate. Recovery test can not efficiently rectify Tg value when TgAb was positive.
Adolescent ; Adult ; Aged ; Autoantibodies ; blood ; immunology ; Child ; Electrochemical Techniques ; False Positive Reactions ; Female ; Graves Disease ; blood ; Hashimoto Disease ; blood ; Humans ; Luminescent Measurements ; methods ; Male ; Middle Aged ; Thyroglobulin ; blood ; immunology ; Young Adult