The effect of vitamin D on thyroid autoimmunity in euthyroid men with autoimmune thyroiditis and testosterone deficiency

BackgroundAutoimmune (Hashimoto’s thyroiditis) is characterized by a strong female preponderance, which may suggest that sex hormones have an impact on thyroid autoimmunity. The aim of this study was to investigate whether testosterone determines vitamin D action on thyroid antibody titers and thyroid function tests in men with autoimmune thyroiditis and low testosterone levels.MethodsThe study included 36 men with testosterone deficiency, 17 of whom had been treated for at least 26 weeks with oral testosterone undecanoate (120 mg daily). Because of coexistent euthyroid Hashimoto’s thyroiditis, all participants were then treated with vitamin D (100 μg daily). Serum titers of thyroid peroxidase and thyroglobulin antibodies, serum levels of thyrotropin, free thyroid hormones, testosterone and 25-hydroxyvitamin D, as well as Jostel’s thyrotropin index, SPINA-GT and SPINA-GD were assessed before vitamin D treatment and 26 weeks later.ResultsWith the exception of testosterone levels, there were no significant differences between both study groups in serum hormone levels, antibody titers and thyroid function tests. All participants completed the study. In addition to increasing 25-hydroxyvitamin D levels, vitamin D increased SPINA-GT and reduced thyroid peroxidase and thyroglobulin antibody titers. In testosterone-treated men, vitamin D increased testosterone levels. Vitamin D did not affect serum levels of thyrotropin, free thyroid hormones, Jostel’s thyrotropin index and SPINA-GD. Treatment-induced changes in thyroid antibody titers and SPINA-GT were more pronounced in testosterone-treated than testosterone-naïve men.ConclusionsThe obtained results suggest that the beneficial effect on thyroid autoimmunity and thyroid secretory function is stronger in men receiving testosterone therapy.     

Screening for thyroid disease and iodine deficiency

The high global prevalence of iodine deficiency and autoimmune thyroid disorders and the mental and physical consequences of these disorders creates a huge human and economic burden that can be prevented, in large part, by early detection and appropriate preventative or therapeutic measures. The availability of sophisticated, sensitive and accurate laboratory testing procedures provides an efficient and effective platform for the application of screening for these disorders. Measurement of urine iodine concentration (UIC) in school children or pregnant women is the recommended indicator for screening populations for iodine deficiency. The severity of the iodine deficiency is classified according to the UIC. Measurement of serum thyrotropin (TSH) as an indicator for population iodine deficiency is used only in neonates and is supplementary to UIC screening. Other indicators such as goitre rates, thyroid function and serum thyroglobulin levels are useful adjunctive but not frontline process indicators. The human and economic benefits of screening for congenital hypothyroidism by measurement of heel-prick TSH have been well documented and justify its universal application. Using this measurement for monitoring population iodine intake is recommended by the World Health Organization but further validation is required before it can be universally recommended. Subclinical thyroid dysfunction is readily detected by current highly sensitive serum TSH assays and its prevalence appears to increase with age, varies with iodine intake and ethnicity and may occur in up to 20% of older age people. Subclinical hyperthyroidism is the less common disorder and screening cannot be justified because of its low prevalence and minimal or insignificant clinical effects. The argument for screening for subclinical hypothyroidism in middle-aged and older women is stronger but lacks evidence of benefit from randomised controlled trials or cost benefit analyses of therapeutic intervention, so it cannot currently be recommended. The publication of recent Clinical Practice Guidelines for management of thyroid disease in pregnancy from the American Endocrine Society and American Thyroid Association provide persuasive arguments for early detection and treatment of overt and subclinical hypothyroidism to prevent obstetric complications and potential neurocognitive disorders in the offspring. Given the indisputable benefits of therapy, the sooner thyroid dysfunction is detected, before or as early as possible in gestation, the more likely there will be a better outcome. Because of the limitations of targeted case detection in women at risk of subclinical hypothyroidism, there has been a gradual shift in opinion to universal TSH screening of all women as soon as practicable in pregnancy. While a positive association exists between the presence of anti-thyroid antibodies and increased pregnancy loss, universal screening of all pregnant women for underlying autoimmune thyroid disease is difficult to justify until there is evidence of beneficial outcomes from randomised controlled trials. Vigorous and liberal targeted case detection remains the recommended strategy to address this problem.     

孕期TPOAb和TgAb阳性对新生儿甲状腺功能的影响

目的:探讨孕期妇女甲状腺过氧化物酶抗体(TPOAb)与甲状腺球蛋白抗体(TgAb)阳性对新生儿甲状腺功能的影响.方法:264例妊娠期妇女根据TPOAb、TgAb检测结果分为TPOAb阳性组与阴性组、TgAb阳性组与阴性组,分别对比TPOAb阳性组与阴性组、TgAb阳性组与阴性组新生儿足跟血促甲状腺激素(TSH)水平、亚临床甲减发生率,并分析孕妇TPOAb、TgAb与新生儿TSH相关性.结果:TPOAb阳性组与TgAb阳性组新生儿TSH水平、亚临床甲减发生率均显著高于TPOAb阴性组与TgAb阴性组;孕妇TPOAb及TgAb水平均与新生儿TSH水平呈显著正相关.结论:孕期TPOAb与TgAb阳性孕妇的新生儿TSH水平及亚临床甲减发生率明显增高,应加强孕期TPOAb与TgAb阳性孕妇所产新生儿的早期甲状腺功能筛查,并及干预,降低临床甲减发生率,促使患儿健康发育成长.     

甲状腺球蛋白抗体对电化学发光免疫分析法测定甲状腺球蛋白的影响

采用电化学发光免疫分析法(ECLIA)同时测定甲状腺球蛋白(Tg)、自身甲状腺球蛋白抗体(TgAb)值,并用回收实验研究TgAb对Tg测定值的影响。甲状腺疾病患者血样84例,测定Tg、TgAb。回收实验分为三组。第一组分别加入50、100和200 ng/ml的标准Tg;第二组TgAb≥4 000 IU/ml的血样对倍稀释5次,分别测定Tg、TgAb值,并加入100 ng/ml标准Tg;第三组TgAb浓度梯度组,分别加入100 ng/ml标准Tg。计算回收率(R)。结果显示血清对倍稀释后,TgAb实测值逐渐下降;Tg实测值、Tg计算值逐渐上升,两者的差值随稀释倍数的增加而增大。当R<80%时,有22人(91.7%)TgAb>115 IU/ml。ECLIA测定Tg时,TgAb的干扰导致Tg测定值低于真实值,并呈浓度依赖性。TgAb的存在是导致回收率降低的主要原因。     

应用血液测定实验室诊断自身免疫性甲状腺疾病

目的探讨甲状腺球蛋白抗体(TG-Ab)、甲状腺过氧化物酶抗体(TPO-Ab)、游离三碘甲腺原氨酸(FT3)、游离甲状腺素(FT4)对自身免疫性甲状腺疾病(AITD)的临床应用价值。方法采用化学发光免疫分析法定量检测153例自身免疫性甲状腺疾病患者、74例非自身免疫性甲状腺疾病患者和71例健康对照组血清中的TG-Ab、TPO-Ab、FT3、FT4。结果不同自身免疫性甲状腺疾病患者之间和自身免疫性甲状腺疾病患者与非自身免疫性甲状腺疾病患者及正常健康人群之间其TG-Ab、TPO-Ab、FT3、FT4水平差异有统计学意义。AITD组TG-Ab和TPO-Ab水平与非AITD组、健康对照组比较差异有统计学意义(P<0.01),桥本甲状腺炎组TG-Ab和TPO-Ab水平与Graves病组比较差异有统计学意义(P<0.01),桥本甲亢组和Graves病组FT3、FT4水平差异无统计学意义(P>0.05),而TPO-Ab、TG-Ab差异有统计学意义(P<0.01)。结论 TG-Ab、TPO-Ab、FT3、FT4四项指标对AITD的诊断及鉴别诊断有重要临床意义。     

The effect of vitamin D and selenomethionine on thyroid antibody titers,hypothalamic-pituitary-thyroid axis activity and thyroid function tests in men with Hashimoto’s thyroiditis: A pilot study

Background

Both selenium and vitamin D were found to reduce thyroid antibody titers in women with Hashimoto’s thyroiditis.

不同含碘剂量中药复方对AIT大鼠IL-1,4,6及TNF-α影响的研究

目的:观察不同剂量含碘中药复方对实验性自身免疫性甲状腺炎(AIT)大鼠的自身抗体、白介素-1、4、6(IL-1、4、6)及肿瘤坏死因子-α(TNF-α)的影响,筛选出治疗AIT中药复方中含碘中药的最佳剂量,并探讨其作用机制。方法:选用普通级SD雌性大鼠75只,取15只为正常组后其余60只进行造模,造模完成后分成4组:模型组、中药低剂量组、中剂量组、高剂量组。酶联免疫法检测各组大鼠的甲状腺抗体,IL-1、4、6,TNF-α水平。结果:中药各治疗组与模型组血清自身抗体,IL-1、4、6及TNF-α比较均有统计学差异(P<0.05),其中中药中、高剂量组与低剂量组比较有统计学差异(P<0.05),中剂量组与高剂量组比较无统计学差异(P>0.05)。结论:中药复方软坚消瘿汤能够通过降低血清自身抗体,IL-1、4、6及TNF-α水平起到有效治疗自身免疫性甲状腺炎的作用,含碘中药海藻、昆布剂量在20～30克之间疗效最佳。     

自身甲状腺球蛋白抗体阳性时三种测定甲状腺球蛋白浓度方法比较

用双抗体法、IRMA和化学发光法测定了120例自身甲状腺球蛋白抗体(TgAb)阳性患者的甲状腺球蛋白(Tg)浓度. 并按疾病类别、甲状腺功能状况以及自身抗体浓度高低分成三组, 结果显示: IRMA和化学发光法测得Tg值明显高于双抗体法, 甲状腺功能亢进及Graves病患者Tg值明显增高;自身抗体TgAb浓度大于1000IU/mL时, 三种方法测得Tg值均明显低下. 提示, 在TgAb阳性患者中, Tg值高低与甲状腺功能状况, 甲状腺疾病类别以及自身抗体浓度高低相关.     

Transient neonatal hypothyroidism is associated with elevated serum anti-thyroglobulin antibody levels in newborns and their mothers

Transient congenital hypothyroidism (TCH) was detected in 6 of 35,067 newborns (1:5845 births) screened in Iran. Antithyroglobulin antibodies positivity was present in 4 of 6 (66.7%) of those with TCH and in 6 of 106 (5.7%) of those with "transient hyperthyrotropinemia and normal" diagnoses (P = .0005), but positivity was similar in newborns with transient hyperthyrotropinemia versus normal neonates (P = .397).     

Effect of human leukocyte antigen class II genes on Hashimoto’s thyroiditis requiring replacement therapy with levothyroxine in the Japanese population

Contribution of the human leukocyte antigen (HLA) subtype to Hashimoto’s thyroiditis (HT) that requires replacement therapy with levothyroxine remains unclear in the Japanese population. The frequencies of HLA DR–DQ haplotypes were compared between patients with HT requiring levothyroxine replacement therapy and the control individuals. We studied 82 patients with HT requiring levothyroxine replacement therapy. The frequencies of DRB1∗08:03–DQB1∗06:01 and DRB1∗09:01–DQB1∗03:03 haplotypes were significantly higher in HT patients, whereas those of DRB1∗13:02–DQB1∗06:04 and DRB1∗15:01–DQB1∗06:02 haplotypes were significantly lower in these patients than in the controls. Deduced from known linkage disequilibria, DRB1∗13:02–DQB1∗06:04 and DRB1∗15:01–DQB1∗06:02 haplotypes share the same DQA1∗01:02 allele. Since DQB1∗06:02 and DQB1∗06:04 molecules differ in the beta chain by 7 residues, these DQB1 genes are very similar. The DQA1∗01:02–DQB1∗06 (DQB1∗06:02 or DQB1∗06:04) haplotype might play a pivotal role in the resistance to HT.