One-year prophylactic treatment of euthyroid Hashimoto's thyroiditis patients with levothyroxine: is there a benefit?

Associations between immune cell traits and autoimmune thyroid diseases: a bidirectional two-sample mendelian randomization study

Autoimmune thyroid diseases (AITDs), mainly including Graves' disease (GD) and Hashimoto's thyroiditis (HT), are common autoimmune disorders characterized by abnormal immune responses targeting the thyroid gland. We conducted a bidirectional two-sample MR analysis using the largest dataset of peripheral immune cell phenotypes from Sardinia, and the AITD dataset from the 10th round of the FinnGen and the UK Biobank project. Instrumental variables (IVs) were rigorously selected based on the three assumptions of MR and analyzed using the Wald ratio, inverse-variance weighted (IVW), MR-Egger, and weighted median methods. Additionally, sensitivity analyses were performed using Cochrane's Q, the Egger intercept, the MR-PRESSO, and the leave-one-out (LOO) method to ensure the robustness of the results. The Steiger test was utilized to identify and exclude potential reverse causation. The results showed that 3, 3, and 11 immune cell phenotypes were significantly associated with the risk of AITD. In GD, the proportion of naive CD4-CD8- (DN) T cells in T cells and the proportion of terminally differentiated CD4+T cells in T cells showed the strongest inducing and protective effects, respectively. In HT, lymphocyte count and CD45 on CD4+T cells showed the strongest inducing and protective effects, respectively. In autoimmune hypothyroidism, CD127 CD8+T cell count and terminally differentiated DN T cell count exhibited the strongest inducing and protective effects, respectively. Through MR analysis, our study provides direct genetic evidence of the impact of immune cell traits on AITD risk and lays the groundwork for potential therapeutic and diagnostic target discovery.

Exposure of Akwesasne Mohawk women to polychlorinated biphenyls and hexachlorobenzene is associated with increased serum levels of thyroid peroxidase autoantibodies

Persistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and dichlorodiphenyltrichloroethane (p,p'-DDT) were reported to influence immunological activity. As endocrine-disrupting chemicals (EDC), these pollutants may disrupt normal thyroid function and act as catalysts for development of autoimmune thyroid disease by directly and indirectly affecting levels of thyroid peroxidase antibodies (TPOAbs). Native American communities are disproportionately exposed to harmful toxicants and are at an increased risk of developing an autoimmune disease. The aim of this study was to determine the association between POPs and TPOAbs in serum obtained from Native American women. This assessment was used to measure whether increased risk of autoimmune thyroid disease occurred as a result of exposure to POPs. Data were collected from 183 Akwesasne Mohawk women, 21-38 years of age, between 2009 and 2013. Multivariate analyses were conducted to determine the association between toxicant exposure and levels of TPOAbs. In multiple logistic regression analyses, exposure to PCB congener 33 was related to elevated risk of individuals possessing above normal levels of TPOAbs. Further, HCB was associated with more than 2-fold higher risk of possessing above normal levels of TPOAbs compared to women with normal levels of TPOAbs. p,p'-DDE was not associated with TPOAb levels within this study. Exposure to PCB congener 33 and HCB was correlated with above normal levels of TPOAbs, a marker of autoimmune thyroid disease. Additional investigations are needed to establish the causes and factors surrounding autoimmune thyroid disease which are multiple and complex.

Long-term Observation of Thyroid Volume Changes in Hashimoto's Thyroiditis in a Series of Women on or off Levo-Thyroxine Treatment in an Area of Moderate Iodine Sufficiency

CONTEXT

Large variations in thyroid volume (TV) have been reported in Hashimoto's thyroiditis (HT). The need for long-term levo-thyroxine (L-T4) administration in order to control TV, as well as to normalise thyroid function, has not been well defined.

SUBJECTS AND METHODS

Retrospective data on TV in 94 adult women with HT were analysed in an ambulatory setting in Liguria, an area of moderate iodine sufficiency. TV was evaluated by means of ultrasonography (US). Thyroid function, anthropometric data, smoking habits and pharmaceutical drugs were registered at each examination.

RESULTS

At the baseline, an atrophic gland was noted in 16% of the women, and goitre in 13%. The women were evaluated 56 and 102 months after the baseline examination. At the time of each examination, 50%, 78% and 83% of women, respectively, were on L-T4 treatment. Baseline TV was not significantly different in women on/off L-T4 treatment. However, in those on L-T4, TV decreased significantly over the period of follow-up, while in those without L-T4 treatment, it did not change. By the end of the study, the percentage of L-T4-treated women with an atrophic gland had increased to 27%, and that of women with goitre had dropped to 6%; in untreated women, only minor changes were noted. There was a significant negative correlation between TV% change and baseline TSH levels in HT women on L-T4 treatment.

CONCLUSION

The majority of HT women living in an area of moderate iodine sufficiency have normal TV. Moreover, long-term L-T4 treatment can be used to control TV, as well as to maintain normal thyroid parameters.

Evolution of Hashimoto thyroiditis in children with type 1 diabetes mellitus (TIDM)

OBJECTIVES

Treatment of children with Hashimoto thyroiditis (HT) and particularly of those with coexistent diabetes mellitus type 1 (TIDM) and normal/mildly elevated serum TSH is controversial. The aim of the study was to evaluate the natural course of HT in children with TIDM compared with children with no other coexistent autoimmunity and investigate for possible predictive factors of thyroid function deterioration.

METHODS

Data from 96 children with HT, 32 with T1DM (23 girls, nine boys) mean (sd) age: 10.6 (2.3) years, and 64 age and sex-matched without T1DΜ (46 girls, 18 boys), mean (sd) age: 10.2 (2.9) years were evaluated retrospectively. They all had fT4 and TSH values within normal ranges and available data for at least three years' follow-up.

RESULTS

During the follow-up period, 11 children (34.4%) with TIDM exhibited subclinical hypothyroidism and two children (6.2%) progressed to overt hypothyroidism compared to 12 (18.8%) and two (3.1%) among children without TIDM, respectively. Among children with HT, a higher percentage (40.6%) of children with T1DM progressed to subclinical or overt hypothyroidism, compared with children (21.9%) with similar characteristics but without TIDM or other coexistent autoimmunity.

CONCLUSIONS

The annual conversion rate from euthyroidism to hypothyroidism in children with T1DM was significantly higher compared to sex and age-matched children without TIDM. Prospective randomized trials are needed to support the view of an earlier intervention therapy even in milder degrees of thyroid failure in these children.

The Clinical Value and Variation of Antithyroid Antibodies during Pregnancy

Antithyroid antibodies, which include thyroid-stimulating hormone receptor antibodies (TRAbs), thyroid peroxidase antibodies (TPOAbs), and thyroid globulin antibodies (TgAbs), are widely known for their tight association with thyroid autoimmune diseases. The variation in all three kinds of antibodies also showed different trends during and after pregnancy (Weetman, 2010). This article reviewed the the physiological changes, while focusing on the variation of thyroid antibodies concentration in women during and after pregnancy, and adverse consequences related to their elevation. Since abnormal elevations of these antithyroid antibodies may lead to adverse outcomes in both mothers and fetuses, special attention must be paid to the titer of the antibodies during pregnancy. The molecular mechanisms of the variations in those antibodies have yet to be explained. The frequency and timing of thyroid antibody measurement, as well as different reference levels, also remain to be elucidated.

Angioedema in a Patient with Autoimmune Thyroiditis – A Case Report

We present a case of a 29-year-old Bulgarian woman with autoimmune thyroiditis and recurrent angioedema. The patient presented with a one-year-long history of recurrent angioedema and Hashimoto’s thyroiditis. Physical examination showed oedema surrounded by erythema on the forearms, and erythematous, itchy plaques spreading over her face, neck, chest, abdomen, and extremities. Blood tests showed elevated total immunoglobulin E (IgE). The patient had been diagnosed with Hashimoto’s thyroiditis and hypothyroidism. She had been taking levothyroxine 50 μg/d, resulting in a good hormonal control; however, her anti-thyroid peroxidase (anti-TPO) antibodies were high. She was started on methylprednisolone and antihistamines. In three weeks, we observed a good therapeutic response to the treatment and the lesions remitted. IgE dropped within normal range. Levels of anti-TPO antibodies were persistently high. In conclusion, patients with angioedema should be tested for thyroid autoimmunity. Further delve into the pathogenesis of angioedema in them is warranted in order to explore the possibility of an underlying atopy in those not responding to the standard treatment with levothyroxine.

Vitamin D Status and Thyroid Autoantibodies in Autoimmune Thyroiditis

A lack of vitamin D seems to be related to autoimmune diseases including autoimmune thyroiditis (AIT). This study intends to determine the correlation between improvement of 25-hydroxyvitamin D [25(OH)D] levels and AIT in patients from an outpatient endocrine clinic in Frankfurt, Germany. This study included 933 patients with thyroid peroxidase antibodies (anti-TPO-Ab) ≥34 kIU/l, including most patients with clear AIT due to a concurrent sonographic evidence of reduced echogenicity. We performed clinical evaluation and laboratory analysis at five points in time within two years retrospectively. Due to a high dropout rate within the observation period, we excluded the last two time points from analysis. Data from 933 AIT patients revealed 89% having vitamin D deficiency or insufficiency [25(OH)D <75 nmol/l] with a median 25(OH)D level of 39.7 nmol/l. At baseline, a weak inverse correlation between 25(OH)D and anti-TPO-Ab was observed during winter (r_s=-0.09, p=0.048*), but not during summer time (p>0.2). We discovered 58 patients having initially a 25(OH)D level < 75 nmol/l (median: 40.2 nmol/l), which improved over time to a 25(OH)D level ≥ 75 nmol/l (median: 83.2 nmol/l, p<0.0005***). Simultaneously, the median anti-TPO-Ab level showed a significant decrease of 25% from 245.8 to 181.3 kIU/l (p=0.036*). A significant reduction of the median anti-TPO-Ab level of 9% was also observed in the control group, which consisted of patients having constantly a 25(OH)D level <75 nmol/l. The result may suggest that in particular patients with 25(OH)D levels < 75 nmol/l benefit from an increase of 25(OH)D levels ≥ 75 nmol/l. Further prospective randomized controlled clinical trials are needed to finally evaluate if vitamin D has immunmodulatory effects in AIT.

Levothyroxine Replacement Alleviates Thyroid Destruction in Hypothyroid Patients With Autoimmune Thyroiditis: Evidence From a Thyroid MRI Study

Background: Autoimmune thyroiditis (AIT) is the most frequent cause of hypothyroidism. Our previous studies have shown that magnetic resonance T1-mapping is a new technique for quantitatively evaluating the degree of thyroid destruction in AIT patients. This study aimed to evaluate the effect of levothyroxine on thyroid destruction in hypothyroid AIT patients using thyroid T1-mapping technique. Methods: This study recruited 29 hypothyroid AIT patients and 18 age- and sex-matched healthy individuals. Thyroid T1-mapping values were measured in all participants and repeated in the AIT patients at 3 months after they achieved a euthyroid state following levothyroxine treatment. Results: Thyroid T1-mapping values were higher in the AIT patients than in the healthy controls (1167.2 ± 163.2 vs. 779.6 ± 83.8 ms, P < 0.01), and levothyroxine treatment significantly decreased the thyroid T1-mapping values of AIT patients (1006.3 ± 114.6 vs. 1167.2 ± 163.2 ms, P < 0.01). Meanwhile, the reduced levels of anti-peroxidase antibody (TPOAb) and anti-thyroglobulin antibody (TgAb) were observed in the AIT patients after levothyroxine treatment [TPOAb: 257.6 (23.9-960.6) vs. 1,287.4 (12.6-2000.0) IU/mL, P < 0.01; TgAb: 53.54 (9.58-386.2) vs. 103.9 (34.2-1,596.8) IU/mL, P < 0.05]. High-sensitivity C-reactive protein (hsCRP) levels showed a descending tendency following levothyroxine treatment, although there was no statistical difference (P > 0.05). Conclusions: In the AIT patients, thyroid T1-mapping values were significantly increased, and levothyroxine treatment significantly decreased the thyroid T1-mapping values of the AIT patients. These results might suggest that levothyroxine treatment alleviates thyroid destruction in hypothyroid AIT patients.

Surgical management of neck pain and headache associated with pediatric hashimoto's thyroiditis

OBJECTIVES/HYPOTHESIS

Case reports of a painful variant of Hashimoto's thyroiditis exist in the literature; however, these cases have only been documented in adult patients and there are no standard treatment guidelines. The aim of this study was to describe an alternative management for Hashimoto's thyroiditis associated with medically intractable head and neck pain in the pediatric population.

STUDY DESIGN

Case series with chart review.

METHODS

The study was conducted in the Section of Pediatric Otolaryngology at the Cleveland Clinic. We retrospectively analyzed pediatric patients (ages 0-18 years) with painful thyroiditis and/or headache who underwent total thyroidectomy from 2005 to 2014 with a clinical diagnosis of Hashimoto's thyroiditis. A thorough chart review was performed, including medical and family history, presenting symptoms, laboratory values, medical and surgical treatment strategies, operative reports, and surgical pathology.

RESULTS

There were 0.02% of patients (5 of 305) who met the criteria of intractable head and or neck pain. All five underwent total thyroidectomy with confirmation of Hashimoto's thyroiditis on surgical pathology. Surgical treatment resulted in complete cervical pain relief and improved headaches with a minimum follow-up of 36 months.

CONCLUSIONS

Hashimoto's thyroiditis is a relatively common form of autoimmune thyroiditis in pediatric patients that uncommonly results in intractable neck pain or headache. In this case series, thyroidectomy was an effective alternative treatment in the pediatric population for medical failures in chronic painful Hashimoto's thyroiditis.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:2213-2217, 2018.

Severe subtype of alopecia areata is highly associated with thyroid autoimmunity

Objectives:

To assess the significance of thyroid autoimmune screening in alopecia areata (AA) patients in Saudi population, and to determine whether there is a difference in thyroid autoimmune susceptibility between mild and severe AA.

Methods:

In a prospective case-control study, we included 50 alopecia totalis (AT) and alopecia universalis (AU) patients, 50 age- and gender-matched patients with localized AA, and 50 age- and gender- matched healthy subjects between March 2015 and August 2015. Patients with AA were consecutively recruited from the hair disorders out-patient clinic of King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia.

Results:

Thyroid autoantibodies (TAAs) were positive in AT/AU (40%), mild AA (14%), and healthy subjects (4%). The frequency of TAAs was significantly higher in patients with AT/AU than in mild AA (p=0.001) and healthy controls (p<0.001). The frequency of thyroid peroxidase antibody (TPO-Abs) was significantly higher in patients with AT/AU than in mild AA and healthy controls (p<0.001 for both). The frequency of TG-Abs was significantly higher in patients with AT/AU (p=0.003) and mild AA (p=0.043) than in healthy controls. Serum TSH level was significantly higher in AT/AU patients than in mild AA patients (p=0.006) and healthy controls (p=0.005).

Conclusion:

Severe subtype of AA is associated with a high risk of autoimmune thyroid disease. This highlights the significance of screening for thyroid abnormalities and TAAs in patients with AT/AU.

The relationship between thyroid antibody titer and levothyroxine dose in patients with overt primary hypothyroidism

BACKGROUND

Both excess and insufficient thyroid hormone replacement may produce adverse effects in various target tissues; therefore, understanding factors that affect achievement of target TSH levels is crucial.

OBJECTIVE

Investigate the relationship between antibody titers and levothyroxine dose.

DESIGN

Retrospective, review of data in medical records.

SETTING

Thyroid center of Fatih Sultan Mehmet Education and Research Hospital, Istanbul, Turkey.

PATIENTS AND METHODS

The study population consisted of patients that had been diagnosed as having overt primary hypothyroidism and were taking levothyroxine for at least one year. The serum TSH level for an euthyroid state was between 0.5-4 mIU/L. The levels of anti-thyroid peroxidase (TPOAb) considered positive for antibodies were < 5.6 IU/mL and for anti-thyroglobulin (TgAb) autoantibodies < 4.10 IU/ mL.

MAIN OUTCOME MEASURE

Daily levothyroxine doses of antibody-positive and negative patients and association of daily drug requirement with antibody titers.

RESULTS

The study population consisted of the 303 patients (273 females and 30 males with the mean [SD] age of 46.6 [13.2] years). In the antibody-positive group (n=210) average daily levothyroxine dose was statistically significantly higher than in the antibody-negative group (n=93) (mean of 78.8 [36.7] vs 64.2 [27.1] mg/day, P=.001, respectively). There was a low but statistically significant positive relationship between the TPOAb (r=0.217, P < .01) and TgAb levels (r=0.158, P < .05) and levothyroxine doses in the antibody-positive group.

CONCLUSION

Antibody titers are positively associated with larger levothyroxine (LT-4) replacement dosing in patients with autoimmune thyroiditis.

LIMITATION

Unknown antibody titers before starting levothyroxine use.

Early thyroxine treatment in Down syndrome and thyroid function later in life

OBJECTIVE

The hypothalamus-pituitary-thyroid (HPT) axis set point develops during the fetal period and first two years of life. We hypothesized that thyroxine treatment during these first two years, in the context of a randomized controlled trial (RCT) in children with Down syndrome, may have influenced the HPT axis set point and may also have influenced the development of Down syndrome-associated autoimmune thyroiditis.

METHODS

We included 123 children with Down syndrome 8.7 years after the end of an RCT comparing thyroxine treatment vs placebo and performed thyroid function tests and thyroid ultrasound. We analyzed TSH and FT4 concentrations in the subgroup of 71 children who were currently not on thyroid medication and had no evidence of autoimmune thyroiditis.

RESULTS

TSH concentrations did not differ, but FT4 was significantly higher in the thyroxine-treated group than that in the placebo group (14.1 vs 13.0 pmol/L; P = 0.02). There was an increase in anti-TPO positivity, from 1% at age 12 months to 6% at age 24 months and 25% at age 10.7 years with a greater percentage of children with anti-TPO positivity in the placebo group (32%) compared with the thyroxine-treated group (18.5%) (P = 0.12). Thyroid volume at age 10.7 years (mean: 3.4 mL; range: 0.5-7.5 mL) was significantly lower (P < 0.01) compared with reference values (5.5 mL; range: 3-9 mL) and was similar in the thyroxine and placebo group.

CONCLUSION

Thyroxine treatment during the first two years of life led to a mild increase in FT4 almost 9 years later on and may point to an interesting new mechanism influencing the maturing HPT axis set point. Furthermore, there was a trend toward less development of thyroid autoimmunity in the thyroxine treatment group, suggesting a protective effect of the early thyroxine treatment. Lastly, thyroid volume was low possibly reflecting Down-specific thyroid hypoplasia.

Thyroid function in children and adolescents with Hashimoto's thyroiditis after l-thyroxine discontinuation

OBJECTIVE

Thyroid function may recover in patients with Hashimoto's thyroiditis (HT).

DESIGN

To investigate thyroid function and the need to resume l-thyroxine treatment after its discontinuation.

SETTING

Nine Italian pediatric endocrinology centers.

PATIENTS

148 children and adolescents (25 m and 123 f) with HT on treatment with l-thyroxine for at least one year.

INTERVENTION AND MAIN OUTCOME MEASURE

Treatment was discontinued in all patients, and serum TSH and fT4 concentrations were measured at the time of treatment discontinuation and then after 2, 6, 12 and 24 months. Therapy with l-thyroxine was re-instituted when TSH rose >10 U/L and/or fT4 was below the normal range. The patients were followed up when TSH concentrations were between 5 and 10 U/L and fT4 was in the normal range.

RESULTS

At baseline, TSH was in the normal range in 139 patients, and was between 5 and 10 U/L in 9 patients. Treatment was re-instituted after 2 months in 37 (25.5%) patients, after 6 months in 13 patients (6.99%), after 12 months in 12 patients (8.6%), and after 24 months in an additional 3 patients (3.1%). At 24 months, 34 patients (34.3%) still required no treatment. TSH concentration >10 U/L at the time of diagnosis was the only predictive factor for the deterioration of thyroid function after l-thyroxine discontinuation.

CONCLUSIONS

This study confirms that not all children with HT need life-long therapy with l-thyroxine, and the discontinuation of treatment in patients with a TSH level <10 U/L at the time of diagnosis should be considered.

Adding carbimazole to levothyroxine increases triiodothyronine and improves outcome in patients with primary hypothyroidism: a preliminary study from Egypt

BACKGROUND

Many hypothyroid patients are not tolerant and not satisfied with levothyroxine (LT4). Older studies used large doses of both carbimazole and LT4 for Hashimoto's thyroiditis (HT), because Graves' disease (GD) and HT were considered as very closely related syndromes produced by thyroid autoimmunity.

OBJECTIVE

The aim of the study was to determine the outcome after adding small doses of carbimazole to reduced doses of LT4 for patients with primary hypothyroidism, who are unable to tolerate LT4.

METHODS

The study is a non-randomized, single arm, interventional study. It included 19 female patients diagnosed with primary hypothyroidism who could not tolerate LT4. Subjects were recruited from the outpatient clinic of AL-Azhar University Hospital in Damietta, Egypt from January to March 2015. They were divided into two groups; group 1 included 10 patients with HT and 2 patients with non-specified primary hypothyroidism, and group 2 included 7 patients with subtotal thyroidectomy for GD. All patients received carbimazole (10 mg/day) beside LT4 (25 μg thrice/week) for 10 weeks. Statistical analysis of the data was done by SPSS version 20, using paired-sample t-test, ANOVA, Chi square, and Pearson coefficient test.

RESULTS

There was significant increase in free triiodothyronine (FT3) in addition to significant improvement in depression and LT4 tolerance in the whole population. There was non-significant improvement in TSH in group 1 (p=0.053). Surprisingly, in group 2, in spite of significant increase in TSH (p=0.007) and non-significant decrease in free thyroxine (FT4), there was non-significant increase in FT3. Whether carbimazole improves the pathology of the hypothyroid gland or the peripheral deiodination of T4 to T3 (where the serum and tissue levels of the latter may be responsible for improvement of symptoms) is in need of investigation.

CONCLUSIONS

Adding carbimazole to LT4 improves FT3, LT4 tolerance, and depression in primary hypothyroid female patients. Further studies are required to determine the appropriate doses of this regimen in different cases.

CLINICAL TRIAL REGISTRATION

This study was registered at Thai Clinical Trials Registration center (http://www.clinicaltrials.in.th) with registration ID: TCTR20170123003.

FUNDING

The study received no fund or grant.

Five-Year Prospective Evaluation of Thyroid Function Test Evolution in Children with Hashimoto's Thyroiditis Presenting with Either Euthyroidism or Subclinical Hypothyroidism

BACKGROUND

Whether the course of thyroid function in Hashimoto's thyroiditis (HT) differs in children who present with either euthyroidism or subclinical hypothyroidism (SH) has been incompletely investigated.

AIM

Using a five-year prospective evaluation of 234 children with HT and no prognostic risk factors, this study investigated whether the evolution of the thyroid status is influenced by the biochemical pattern at initial diagnosis.

RESULTS

In the entire series, thyrotropin values significantly increased during follow-up, while free thyroxine values decreased and the proportion of children with a thyroid dysfunction increased from 27.3% to 47.4% (p = 0.0001). An increasing proportion of cases with severe thyroid dysfunction was identified, especially among the 64 patients presenting with SH (group B), but also among the 170 children presenting with euthyroidism (group A) at initial diagnosis. At the end of follow-up, the prevalence of children with overt hypothyroidism was 12.3% in group A compared with 31.2% in group B (p = 0.0007). In the overall population, however, the majority of patients (52.6%) exhibited biochemical euthyroidism at the end of follow-up.

CONCLUSIONS

Children with HT may develop a deterioration of thyroid status during the first five years of disease. Such a trend may be observed, even in the patients who initially present with a mild biochemical picture (either SH or euthyroidism). A total of 57.1% of initially euthyroid children remain euthyroid, and 40.6% of patients with initial SH normalize thyroid function within five years after HT diagnosis. The patients presenting with SH are more prone to the risk of developing severe thyroid dysfunction over time.

Levothyroxine Treatment of Euthyroid Children with Autoimmune Hashimoto Thyroiditis: Results of a Multicenter, Randomized, Controlled Trial

BACKGROUND

Levothyroxine (L-T4) treatment of euthyroid children with Hashimoto thyroiditis (HT) is a controversial issue.

PATIENTS AND METHODS

We conducted a prospective, randomized, controlled clinical trial. Out of 79 identified euthyroid patients, 59 started the study; 25 patients (21 female, 4 male; age: 11.8 ± 2.3 years) received L-T4 at a mean dose of 1.6 µg/kg (SD, 0.8) daily, and 34 (27 female, 7 male; age: 12.6 ± 1.2 years) were not treated. Patients developing subclinical hypothyroidism during follow-up (n = 13) were treated with L-T4 and removed from the observation group. As the main outcome measures, thyroid gland volume (determined by ultrasound) as well as serum levels of TSH, free T4, and antibodies against thyroid peroxidase and thyroglobulin were assessed every 6 months for 36 months.

RESULTS

At the start, the mean thyroid volume (standard deviation score, SDS) was 2.5 in the treatment group and 1.6 in the observation group. There was a constant decline in mean thyroid volume (SDS) from 2.13 (month 12) to 1.12 (month 30) in the treated group, with a delta thyroid volume of -1.01 SDS. In the observation group, the mean delta thyroid volume increased to +0.27 SDS. The change of the delta thyroid volume was statistically significantly different between both groups during the 12- and 30-month time points (p < 0.05). L-T4 had no effect on thyroid function and serum thyroid antibodies.

CONCLUSIONS

L-T4 treatment can decrease the thyroid volume in euthyroid children with HT, but the effect is limited to a definite time period.

The impact of levothyroxine sodium treatment on oxidative stress in Hashimoto's thyroiditis

OBJECTIVE

Although several studies reported increased oxidative stress in Hashimoto's thyroiditis (HT), the effect of levothyroxine treatment on oxidative status is not studied extensively. Therefore, we conducted this study to investigate the effects of levothyroxine replacement on oxidative stress in HT.

DESIGN AND METHODS

Thirty-six patients recently diagnosed with HT-related hypothyroidism and 36 healthy controls were included in the study. Levothyroxine replacement was started to patients with hypothyroidism, and had been followed-up for 6 months.

RESULTS

Mean basal serum total antioxidant status (TAS), total thiol, arylesterase, and paraoxonase 1 (PON1) levels were significantly lower, and serum total oxidant status (TOS) and oxidative stress index (OSI) were significantly higher in the patients with hypothyroid than the controls. In the hypothyroid group serum TAS, total thiol, arylesterase, and PON1 levels increased and serum TOS and OSI levels decreased significantly after levothyroxine treatment. Pretreatment serum TAS, total thiol, PON1, and arylesterase levels were positively correlated with free levothyroxine (fT4) and negatively correlated with thyroid-stimulating hormone (TSH), antithyroid peroxidase (anti-TPO), and antithyroglobulin (anti-TG) levels. Also, pretreatment serum TOS and OSI levels were negatively correlated with fT4 levels and positively correlated with TSH, anti-TPO, and anti-TG. We have also found that the fT4 and anti-TPO levels are independent predictors of the oxidative stress parameters in stepwise multivariable linear regression analysis.

CONCLUSION

This study suggests that levothyroxine replacement decreases oxidant status and increases antioxidant status following the 6 months of levothyroxine replacement in hypothyroidism that develops in accordance with the HT.

A randomized-controlled, double-blind study of the impact of selenium supplementation on thyroid autoimmunity and inflammation with focus on the GPx1 genotypes

PURPOSE

To analyze the impact of selenium supplementation on serum antiTPO levels and thyroid echogenicity in patients with CAT, evaluating the response in subgroups with different GPx1 genotypes.

METHODS

CAT patients (n = 55) with positive antiTPO were randomized to selenomethionine (SeMet) 200 μg daily (n = 28) or placebo (n = 27) for 3 months. Assessments included GPx1 genotyping at baseline and serum levels of plasma selenium, erythrocyte GPx1 activity, antiTPO and thyroid echogenicity at baseline, and 3 and 6 months.

RESULTS

In the SeMet group, the increase in plasma levels of selenium and erythrocyte GPx1 activity was similar among patients with different GPx1 genotypes. In the overall cohort, patients randomized to SeMet showed a 5 % decrease in antiTPO levels at 3 months (p = non-significant) and 20 % at 6 months (p < 0.001 versus 3 months). In contrast, patients in the placebo group did not show significant changes in antiTPO levels at any time point. Subgroup analysis showed that patients with different GPx1 genotypes presented comparable responses in antiTPO levels and echogenicity index to SeMet.

CONCLUSIONS

Selenium supplementation decreased serum antiTPO levels in CAT patients, with similar response among patients with different GPx1 genotypes.

Serum 25-Hydroxyvitamin D and Parathyroid Hormone Levels in Non-Lactating Women with Post-Partum Thyroiditis: The Effect of L-Thyroxine Treatment

Vitamin D deficiency seems to be implicated in the onset and progression of some autoimmune disorders. No previous study has investigated vitamin D homeostasis in post-partum thyroiditis. We compared 25-hydroxyvitamin D and parathyroid hormone (PTH) levels between four groups of non-lactating women who gave birth within 12 months before the beginning of the study: hypothyroid women with post-partum thyroiditis (group A; n = 14), euthyroid females with post-partum thyroiditis (group B; n = 14), women with non-autoimmune hypothyroidism (group C; n = 16) and healthy euthyroid females without thyroid autoimmunity (group D; n = 15). In the second part of the study, groups A and C were treated for 6 months with L-thyroxine. Serum levels of 25-hydroxyvitamin D were lower, while PTH higher in patients with post-partum thyroiditis than in patients without thyroid autoimmunity. They were also lower (25-hydroxyvitamin D) or higher (PTH) in group A than in group B, as well as in group C in comparison with group D. L-thyroxine treatment increased 25-hydroxyvitamin D and reduced PTH levels only in hypothyroid women with post-partum thyroiditis. Baseline levels of 25-hydroxyvitamin D correlated with thyroid antibody titres, thyroid function and circulating PTH levels, while the effect of L-thyroxine on serum levels of this vitamin correlated with the changes in thyroid antibody titres and PTH levels. The results of our study suggest the association of vitamin D status with post-partum thyroiditis and L-thyroxine treatment of this disorder.

High prevalence of autoimmune thyroiditis in children and adolescents with vitiligo

BACKGROUND/AIMS

Vitiligo is considered to be an autoimmune disease and is known to be associated with other autoimmune diseases, particularly affecting the thyroid. In children and adolescents this association has been reported in only a few studies, with varying results. The aim of this study was to examine thyroid function and prevalence of thyroid autoimmunity in children and adolescents with vitiligo and to investigate the utility of screening.

METHODS

Two hundred and sixty patients with vitiligo were enrolled. Plasma TSH, FT4 and anti-thyroid peroxidase (TPO) antibody concentrations were measured. The prevalence of thyroid dysfunction and autoimmunity were compared to the general healthy paediatric population.

RESULTS

Autoimmune thyroiditis (AIT) with thyroid hormone disturbances was diagnosed in 16 patients (6.2%). This is significantly higher than the prevalence reported in the general healthy paediatric population. Increased levels of anti-TPO antibodies (= 30 kU/l), without thyroid hormone disturbances, were found in 27 patients (10.5%).

CONCLUSION

The prevalence of AIT in children and adolescents with vitiligo is significantly higher than in the general population. It may be advantageous to screen thyroid function and antibody levels in all paediatric patients with non-segmental vitiligo. To strengthen recommendations on screening, research on the burden for patients and cost-effectiveness is needed.

Sequential elevation of autoantibodies to thyroglobulin and glutamic acid decarboxylase in type 1 diabetes

We have previously reported the high levels of glutamic acid decarboxylase 65 autoantibodies (GAD65A) in patients with type 1 diabetes and autoimmune thyroid disease. Here we describe a 32-year-old Japanese female with a thirteen-year history of type 1 diabetes whose levels of GAD65A were elevated just after the emergence of anti-thyroid autoimmunity. At 19 years of age, she developed diabetic ketoacidosis and was diagnosed with type 1 diabetes. She had GAD65A, insulinoma-associated antigen-2 autoantibodies (IA-2A), and zinc transporter-8 autoantibodies (ZnT8A), but was negative for antibodies to thyroid peroxidase (TPOAb) and thyroglobulin (TGAb) at disease onset. ZnT8A and IA-2A turned negative 2-3 years after the onset, whereas GAD65A were persistently positive at lower level (approximately 40 U/mL). However, just after the emergence of TGAb at disease duration of 12.5 years, GAD65A levels were reelevated up to 5717 U/mL in the absence of ZnT8A and IA-2A. Her thyroid function was normal and TPOAb were consistently negative. She has a HLA-DRB1*03:01/*04:01-DQB1*02:01/*03:02 genotype. Persistent positivity for GAD65A might be associated with increased risk to develop anti-thyroid autoimmunity.

Thyrotropin-blocking autoantibodies and thyroid-stimulating autoantibodies: potential mechanisms involved in the pendulum swinging from hypothyroidism to hyperthyroidism or vice versa

BACKGROUND

Thyrotropin receptor (TSHR) antibodies that stimulate the thyroid (TSAb) cause Graves' hyperthyroidism and TSHR antibodies which block thyrotropin action (TBAb) are occasionally responsible for hypothyroidism. Unusual patients switch from TSAb to TBAb (or vice versa) with concomitant thyroid function changes. We have examined case reports to obtain insight into the basis for "switching."

SUMMARY

TBAb to TSAb switching occurs in patients treated with levothyroxine (LT4); the reverse switch (TBAb to TSAb) occurs after anti-thyroid drug therapy; TSAb/TBAb alterations may occur during pregnancy and are well recognized in transient neonatal thyroid dysfunction. Factors that may impact the shift include: (i) LT4 treatment, usually associated with decreased thyroid autoantibodies, in unusual patients induces or enhances thyroid autoantibody levels; (ii) antithyroid drug treatment decreases thyroid autoantibody levels; (iii) hyperthyroidism can polarize antigen-presenting cells, leading to impaired development of regulatory T cells, thereby compromising control of autoimmunity; (iv) immune-suppression/hemodilution reduces thyroid autoantibodies during pregnancy and rebounds postpartum; (v) maternally transferred IgG transiently impacts thyroid function in neonates until metabolized; (vi) a Graves' disease model involving immunizing TSHR-knockout mice with mouse TSHR-adenovirus and transfer of TSHR antibody-secreting splenocytes to athymic mice demonstrates the TSAb to TBAb shift, paralleling the outcome of maternally transferred "term limited" TSHR antibodies in neonates. Finally, perhaps most important, as illustrated by dilution analyses of patients' sera in vitro, TSHR antibody concentrations and affinities play a critical role in switching TSAb and TBAb functional activities in vivo.

CONCLUSIONS

Switching between TBAb and TSAb (or vice versa) occurs in unusual patients after LT4 therapy for hypothyroidism or anti-thyroid drug treatment for Graves' disease. These changes involve differences in TSAb versus TBAb concentrations, affinities and/or potencies in individual patients. Thus, anti-thyroid drugs or suppression/hemodilution in pregnancy reduce initially low TSAb levels even further, leading to TBAb dominance. In contrast, TSAb emergence after LT4 administration may be sufficient to counteract TBAb inhibition. The occurrence of "switching" emphasizes the need for careful patient monitoring and management. Finally, whole genome screening of relatively rare "switch" patients and appropriate Graves' and Hashimoto's controls could provide unexpected and valuable information regarding the basis for thyroid autoimmunity.

L-thyroxine stabilizes autoimmune inflammatory process in euthyroid nongoitrous children with Hashimoto's thyroiditis and type 1 diabetes mellitus

OBJECTIVE

To investigate if L-thyroxine (T4) treatment may influence the clinical course of autoimmune thyroiditis (AIT) or prevent progression to subclinical or overt hypothyroidism in euthyroid nongoitrous pediatric patients with type 1 diabetes mellitus (T1DM) and AIT.

METHODS

The study was performed in four Polish pediatric diabetes centers. Of 330 children with T1DM and AIT followed between 2008 and 2012, 101 received L-T4 and 160 underwent clinical observation for 24 months. Thyroid stimulating hormone (TSH), free T4 (fT4), anti thyroid peroxidase antibody (anti-TPO), anti thyroglobulin antibody (anti-TG), glycosylated hemoglobin (HbA1c) levels, and lipid profile were assessed in all patients. Ultrasonographic evaluation was also performed in all children at each examination.

RESULTS

Patients treated with thyroid hormones had higher TSH levels (3.99; interquantile 3.5 to 4.52 vs. 2.09 mIU/L; interquantile 1.55 to 3.06; pp<0.0001). A fall in TSH level (0.87 mIU/L 95% CI 0.43-1.30; pp<0.0001) was documented after the first year of treatment. FT4 level did not differ between the groups at baseline (p=0.7434), but rose in the treatment group and fell in the control group [mean difference 0.78 95% CI-0.22-1.53 pmol/L (p=0.02) after 12 months and 0.98 95% CI 0.04-1.76 (p=0.005) after 24 months]. Higher levels of anti-TPO were initially found in the treated patients (pp<0.0001) and significantly decreased over the 24-month period (pp<0.0001). Children in the treatment group had higher anti-TG levels (pp<0.0001), which showed a borderline decrease (p=0.08) in time. In the control group, anti-TG levels rose marginally (p=0.06) during the study.

CONCLUSIONS

The data demonstrate that treatment with L-T4 in euthyroid pediatric patients with T1DM and AIT stabilizes autoimmune inflammation in the thyroid gland and is to be recommended as soon as the diagnosis is established.

Hashimoto's thyroiditis in patients with normal thyroid-stimulating hormone levels

Hashimoto's thyroiditis (HT) is one of the most common autoimmune endocrine disorders and often leads to hypothyroidism. It has been shown to substantially affect a patient's quality of life. Associated conditions and diseases were thought to be attributable to hypothyroidism. Yet, many patients still suffer from various symptoms even though all thyroid parameters are within the normal range. Independently of thyroid gland function, HT is associated with a wide range of organ-specific and non-organ-specific autoimmune disorders, as well as other diseases, including neuropsychological/psychiatric deficits, decreased left ventricular performance, disorders of the gut, fibromyalgia and reproductive health issues, among others. The underlying pathomechanisms remain unclear. Future treatment options might include thyroidectomy, selenium administration, prophylactic levothyroxine supplementation and dehydroepiandrosterone. However, further research is warranted to clarify the main pathophysiologic implications of thyroid autoimmunity and also to establish treatment options for euthyroid patients who suffer from HT-related symptoms and diseases.

Clinical course of Hashimoto's thyroiditis and effects of levothyroxine therapy on the clinical course of the disease in children and adolescents

OBJECTIVE

The aim of this study was to evaluate the clinical course of Hashimoto's thyroiditis (HT) in children and adolescents and the effects of levothyroxine therapy on the clinical course and laboratory findings.

METHODS

The clinical and laboratory data of 101 patients with HT at presentation and during a three-year follow-up period were retrospectively evaluated using patient records.

RESULTS

The mean age of the patients at the time of diagnosis was 12.3 ± 2.90 years and female/male ratio was 5.7/1. The complaint at the time of hospital presentation was goiter in 57.8% of the patients. At baseline, 36.7% of the patients were euthyroid, whereas 32.7% had subclinical hypothyroidism, 16.6 % of subjects were evaluated as hypothyroid. Twelve of the 28 patients who were initially euthyroid and not receiving therapy developed subclinical or overt hypothyroidism during the first 18 months of the follow-up period and were started on thyroid medication. At presentation, the mean anti-thyroglobulin (anti-Tg) and anti-thyroperoxidase antibody levels were 450 ± 725 IU/mL and 392 ± 428 IU/mL, respectively and at the end of the follow-up period, a significant decrease was observed in the anti-Tg levels of patients receiving levothyroxine from the beginning.

CONCLUSIONS

Thyroid functions of the patients with HT should be monitored periodically for hypothyroidism. Levothyroxine therapy may positively affect the clinical course of the disease and the antibody titers.

Thyroid autoimmunity and pre-term delivery: brief review and meta-analysis

BACKGROUND

About 10% of women in childbearing age are positive for thyroid antibodies. The presence of such antibodies has been associated with adverse obstetrical outcomes, in particular miscarriage and pre-term delivery, even though the strength of these associations varies widely from one study to another.

AIM

To evaluate from the available data of the literature, the association between thyroid autoimmunity and pre-term delivery.

MATERIALS AND METHODS

MEDLINE, EMBASE, Cochrane Library search from 1990 to 2010. A combination of key words was used to generate 2 subset of citations, one indexing thyroid antibodies and the other indexing pre-term delivery as adverse outcome.

RESULTS

Seven studies, collecting about 23,000 patients were selected. Meta-analysis of the studies showed an association between thyroid autoimmunity and pre-term delivery [odds ratio =1.67 (confidence interval: 1.44- 1.94; p<0.001)].

CONCLUSIONS

The results of the meta-analysis confirmed the association between thyroid autoimmunity and pre-term delivery. A cause-effect relationship has to be still clarified and interventional studies are required.

Factors for thyroid autoimmunity in children and adolescents with type 1 diabetes mellitus

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is associated with an autoimmune reaction to thyroid antigens including thyroid peroxidase (anti-TPO) and thyroglobulin (anti-Tg).

AIMS

We determined in children with T1DM the relationship of positive anti-thyroid antibodies to potential risk factors, including, age, gender, duration of diabetes, and glutamic acid decarboxylase antibodies (anti-GAD).

MATERIALS AND METHODS

We studied 144 children and adolescents with T1DM. Their age was 12.3 +/- 4.6 (mean +/- SD) years, and duration of diabetes was 4.6 +/- 3.8 years. Anti-thyroid antibodies were determined using a luminescence method and anti-GAD using an enzyme-linked immunosorbent assay.

RESULTS

The prevalence rates of anti-thyroid antibodies among the children with T1DM in our study were: anti-TPO (17.4%), anti-Tg (11.1%), and of both anti-thyroid antibodies (10.4%). The presence of serum anti-thyroid antibodies was positively associated with age (16.6 years in those with positive tests versus 12.0 years in those with negative tests, P = 0.027), duration of diabetes (7.4 versus 4.3 years, P = 0.031), and serum TSH (Thyroid-stimulating hormone) levels (4.8 versus 2.3 microIU/mL, P = 0.002). The presence of both anti-thyroid antibodies was associated with female sex (boys: 4/75 (5.3%), girls: 11/69 (15.9%), chi-square = 6.44, P = 0.04). Subclinical autoimmune thyroiditis (SAIT) was present in 55.5% of the patients with thyroid antibody-positivity and was positively associated with age (16.6 versus 12.0 years, P = 0.001) and diabetes duration (7.6 versus 4.2 years, P = 0.001). Multiple logistic regression analysis revealed that the development of anti-thyroid antibodies was predicted by: 1) the presence of anti-GAD (odds ratio (OR) 1.45, 95% confidence interval (CI) 1.09-1.92), 2) the presence of a second anti-thyroid antibody (OR 134.4, 95% CI 7.7-2350.3), and 3) older age (OR 22.9, 95% CI 1.13-463.2).

CONCLUSIONS

Thyroid autoimmunity was associated with female gender, increasing age, long diabetes duration, the persistence of anti-GAD, and with TSH elevation, indicating subclinical hypothyroidism.

Long-term follow-up of antithyroid peroxidase antibodies in patients with chronic autoimmune thyroiditis (Hashimoto's thyroiditis) treated with levothyroxine

BACKGROUND

A number of studies show that the serum levels of antithyroid peroxidase antibodies (TPO-Ab) in patients with Hashimoto's thyroiditis decline during levothyroxine treatment, but do not provide quantitative data or report the fraction of patients in whom test for TPO-Ab became negative ("normalization percentage"). The objective of the present study was to provide this information.

METHODS

This was a retrospective study of TPO-Ab concentrations in 36 women and 2 men (mean age 51 +/- 16 years; range 19-81 years) with Hashimoto's thyroiditis as defined by the following criteria: elevated plasma TPO-Ab and typical hypoechogenicity of the thyroid in high-resolution sonography at first presentation or during follow-up and low pertechnetate uptake in thyroid scintigraphy. When first studied 17 women and 1 man were not yet taking levothyroxine. The remaining 20 patients were receiving levothyroxine. At initial examination 18 patients had serum thyroid-stimulating hormone (TSH) concentrations above normal. Results of up to eight (mean = 5.8) measurements obtained over a mean period of 50 months while patients were receiving levothyroxine were analyzed. In addition, serum TSH, free triiodothyronine (fT3), and free thyroxine (fT4) were measured, and ultrasound of the neck was performed at each follow-up examination.

RESULTS

In terms of TPO-Ab levels, 35 of 38 patients (92%) had a decrease, 2 patients had undulating levels, and 1 patient had an inverse hyperbolic increase in her TPO-Ab levels. In the 35 patients in whom there were decreasing TPO-Ab values, the mean of the first value was 4779 IU/mL with an SD of 4099 IU/mL. The mean decrease after 3 months was 8%, and after 1 year it was 45%. Five years after the first value, TPO-Ab levels were 1456 +/- 1219 IU/mL, a decrease of 70%. TPO-Ab levels became negative, < 100 IU/mL, in only six patients, a normalization percentage of 16%. There were no correlations between changes in thyroid volume and changes in TPO-Ab.

CONCLUSION

Serum TPO-Ab levels decline in most patients with Hashimoto's thyroiditis who are taking levothyroxine, but after a mean of 50 months, TPO-Ab became negative in only a minority of patients.

Early treatment with L-thyroxine in children and adolescents with type 1 diabetes, positive thyroid antibodies, and thyroid gland enlargement

AIM

To investigate whether early treatment with l-thyroxine may prevent deterioration of thyromegaly and progression to subclinical or clinical hypothyroidism in pediatric patients with type 1 diabetes, positive thyroid antibodies, and ultrasound abnormalities of the thyroid gland.

METHODS

The development of thyroid gland volume and function in patients without L-thyroxine treatment (group A, n = 8) was assessed and compared with that in patients receiving L-thyroxine treatment (group B, n = 7) with median follow-up time of 2.0 yr (range 0.6-3.0 yr). Standard deviation score (SDS) of thyroid gland volume was calculated according to gender- and age-corresponding data.

RESULTS

Median thyroid gland volume SDS at study entry was 4.8 (range 2.0-15.3) in group A and 5.6 (3.6-13.9) in group B. At follow-up, median thyroid volume SDS has increased by 0.8 (-3.9 to 6.0) at 1 yr and by 2.0 (-4.5 to 10.9) at 2 yr in group A but decreased significantly by -3.4 (-10.0 to 0.4) and -5.3 (-12.3 to -1.7) in group B, respectively. The change of thyroid gland volume was significantly different between the two groups (p = .043 and .032, respectively). In group A, three of eight patients without therapy developed subclinical hypothyroidism with thyroid-stimulating hormone elevation.

CONCLUSION

These data demonstrate that treatment with L-thyroxine in patients with diabetes, positive thyroid antibodies, and elevated gland volume leads to a significant reduction of thyromegaly. Prospective randomized clinical trials are required to prove these preliminary findings.

Levothyroxine in euthyroid autoimmune thyroiditis and type 1 diabetes: a randomized, controlled trial

CONTEXT

Patients with type 1 diabetes (T1D) have an increased risk of autoimmune thyroiditis (AIT).

OBJECTIVE

Our objective was to determine whether levothyroxine (l-T(4)) treatment prevents the clinical manifestation of AIT in euthyroid subjects with T1D.

DESIGN AND SETTING

We conducted a prospective, randomized, open, controlled clinical trial at six tertiary care centers for pediatric endocrinology and diabetes.

PATIENTS

Of 611 children and adolescents with T1D, 89 individuals (14.5%) were identified with positive thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb), or both. Of these, 30 patients (age, 13.3 +/- 2.1 yr) met the inclusion criteria and were randomized to receive l-T(4) (n = 16 patients) or no treatment (n = 14 patients).

INTERVENTION

l-T(4) (1.3 microg/kg daily) was given for 24 months in the treatment group, followed by an additional observation period of 6 months in both groups.

MAIN OUTCOME MEASURES

Thyroid gland volume (as determined by ultrasound), serum levels of TSH, thyroid hormones, TPOAb, and TgAb were assessed every 6 months for 30 months.

RESULTS

Mean thyroid volume decreased in the treatment group after 24 months (-0.60 sd score) and increased in the observation group (+ 1.11 sd score; P = 0.0218). Serum thyrotropin, free T(4), TPOAb, and TgAb levels were not significantly different in both groups during the entire study period. Hypothyroidism developed in three individuals treated with l-T(4) and in four untreated patients (conversion rate, 9.3% per year).

CONCLUSIONS

In this study in euthyroid patients with AIT and T1D, l-T(4) treatment reduced thyroid volume but had no effect on thyroid function and serum autoantibody levels.

Long-term outcome of hormonal status in Taiwanese children with Hashimoto's thyroiditis

The objective of this prospective study was to evaluate both thyroid function in children with Hashimoto's thyroiditis and the necessity of lifetime thyroxine replacement therapy. A total of 47 patients with goiter and positive thyroid auto-antibodies participated in the study. Serum thyroxine and thyrotropin levels and titers of thyroid auto-antibodies were checked regularly throughout the follow-up period. At the beginning of the study, 25 patients were diagnosed as euthyroid, but at the end of the study, 22 patients initially diagnosed with euthyroidism remained euthyroid, while eight patients with subclinical hypothyroidism and three patients with overt hypothyroidism had become euthyroid. Thus, of the 22 patients with thyroid dysfunction at diagnosis, subclinical or overt, 11 became euthyroid during the follow-up period. The effect of thyroxine treatment on thyroid auto-antibody titers was not significant.

CONCLUSION

Our data shows that Hashimoto's thyroiditis in children has a benign course and that thyroid function in one half of the patients with thyroid dysfunction at diagnosis reverts to normal. Careful follow-up of thyroid function is important in order to determine the necessity and timing of thyroxine replacement therapy.

Isolation of thyroid cells obtained by fine-needle aspiration biopsy

Usually thyroid cells isolated from tissue obtained by surgery or thyroid cell lines are used to investigate the pathogenesis of autoimmune thyroid diseases. Isolation and cultivation of thyrocytes from fine-needle aspiration biopsy (FNAB) has not yet been published. The aim of this study was to isolate and cultivate thyrocytes from samples of FNAB. FNAB samples were obtained from nine adults and nine children with Hashimoto's thyroiditis (HT). The aspiration material was filtered resulting in small samples of tissue on the surface of the filter membrane. These tissue fragments were digested by collagenase I and dispase II. The yielding cells were cultivated for 3 weeks in Ham's F12 Kaighn's Modification medium in presence of 1 mU/mL bovine thyrotropin (TSH), 10 microg/mL human insulin, 6 microg/mL transferrin, and 10(-8) M hydrocortisone. Finally, isolated thyroid cells were characterized by determination of gene expression of thyrotropin receptor (TSHR), thyroperoxidase (TPO), and thyroglobulin (Tg) using a nested reverse transcriptase-polymerase chain reaction (RT-PCR). Thyroid cells obtained by FNAB can be maintained over a time period of approximately 3 weeks. Depending on the sample size a final number of 1000-14,000 cells was gained per FNAB. In addition, all cells isolated by the described method expressed TPO mRNA. TSHR mRNA was found in 4 samples, whereas 15 samples were Tg mRNA-positive. There were no differences with respect to the expression TSHR and TPO mRNA between samples from adults and children. The isolation and cultivation of thyroid cells obtained by FNAB has been established. In contrast to surgical specimen, this technique provides an easy access to thyrocytes derived from individual patients allowing repeated sampling to investigate the time progression of the chronic disease or the effect of treatment over time.

Effects of prophylactic thyroid hormone replacement in euthyroid Hashimoto's thyroiditis

Hashimoto's thyroiditis is the most frequent autoimmune thyroid disease. L-thyroxine therapy can reduce the incidence and alleviate the symptoms of this disease. The aim of this study was to evaluate the effects of prophylactic L-thyroxine treatment on clinical and laboratory findings of patients who were euthyroid at the time of diagnosis. Thirty-three patients who had diagnosis of euthyroid Hashimoto's thyroiditis were randomized to two groups, one group received prophylactic L-thyroxine treatment and the other was followed-up without treatment. Initial thyroid function tests, autoantibodies, ultrasonography, fine needle aspiration biopsy and peripheral blood lymphocyte subsets were similar in the two study groups. After 15 months of L-thyroxine treatment, there was a significant increase in free T4 and a significant decrease in TSH and anti-thyroglobulin antibody anti-thyroid peroxidase antibody levels. CD8+ cell counts increased in both groups, CD4/CD8 levels decreased significantly because of the increase in CD8+ cell count levels. Though there was no change in cytological findings, ultrasonography showed a decrease in thyroid volume in L-thyroxine receiving patients whereas an increase was detected in patients who were followed without treatment. In conclusion, prophylactic thyroid hormone therapy can be used in patients with Hashimoto's thyroiditis even if they are euthyroid.

HLA-DQ polymorphisms modify the risk of thyroid autoimmunity in children with type 1 diabetes mellitus

OBJECTIVE

Type 1 diabetes mellitus (DM1) is frequently accompanied by thyroid autoimmunity (TAI). The aims of the present study were to estimate the prevalence of TAI and to determine the contribution of HLA-DQA1 and -DQB1 polymorphisms to TAI susceptibility among children with DM1. PATIENTS AND METLHODS: Screening for TAI was performed in 285 children with DM1 by measuring autoantibodies against thyroid peroxidase (anti-TPO) and thyroglobulin (anti-Tg). HLA-DQA1 and -DQB1 were genotyped using PCR-SSP.

RESULTS

Repeated positivity of anti-TPO and/or anti-Tg was found in 45/285 children with DM1 (15.8%). The prevalence was significantly higher in girls than in boys (26.7% vs 6.7%; p<10(-5)). The HLA-DQB1*0302 allele conferred susceptibility to TAI in children with DM1 (OR 2.7, 95% CI 1.1-6.4), while the DQB1*05 alleles acted protectively (OR 0.2, CI 95% 0.08-0.7).

CONCLUSIONS

HLA-DQ polymorphisms significantly modify the risk of TAI in children with DM1.

[Autoimmune thyroiditis. Treatment with thyroid gland hormones in subclinical hypothyroidism or already in euthyroid state?]

In patients with subclinical hypothyroidism thyroid hormone therapy should be recommended more often with respect to analysis of effectiveness and risks. There is no cost-difference between treated patients and those who undergo thyroid hormone controls only, but thyroid hormone therapy probably induces improvement of clinical and laboratory parameters and reduction of cardiovascular risk factors. These therapeutic effects have to be elucidated in clinical prospective studies. Thyroid hormone therapy of patients with autoimmune thyroiditis and still euthyroid function obviously inhibits the autoimmune process and development of hypothyroidism. A final recommendation, however, can be given after the data of clinical studies with larger populations are available.

Thyroid autoimmunity in chronic idiopathic urticaria: implications for therapy

The association between thyroid autoimmunity and chronic idiopathic urticaria has long been recognized, although prevalence rates differ in the studies reported to date (from 12 to 29%). There is, therefore, a strong indication to screen patients affected by chronic urticaria of unknown origin for thyroid antibodies (antithyroperoxidase and antithyroglobulin) and, when positive, for serum thyrotropin to assess thyroid functional status. Less clear is the implication of thyroid autoimmunity for therapy, as most patients with urticaria who have associated thyroid autoimmunity are euthyroid. There is no doubt that cases with clinical or subclinical thyroid dysfunction should undergo treatment with either levothyroxine or antithyroid drugs for hypo- or hyper-function, respectively. Although the best remission rates for symptoms of urticaria have so far been obtained with levothyroxine in patients who are euthyroid, monitoring of thyroid function through serum thyrotropin determination is highly recommended because of the risk of hyperthyroidism, especially in the elderly.

Thyroid autoimmunity in children and adolescents with type 1 diabetes: a multicenter survey

OBJECTIVE

To investigate thyroid autoimmunity in a very large nationwide cohort of children and adolescents with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Data were analyzed from 17,749 patients with type 1 diabetes aged 0.1-20 years who were treated in 118 pediatric diabetes centers in Germany and Austria. Antibodies to thyroglobulin (anti-TG) and thyroperoxidase (anti-TPO) were measured and documented at least once in 7,097 patients. A total of 49.5% of these patients were boys, the mean age was 12.4 years (range 0.3-20.0 years), and the mean duration of diabetes was 4.5 years (range 0.0-19.5 years). A titer exceeding 100 units/ml or 1:100 was considered significantly elevated.

RESULTS

In 1,530 patients, thyroid antibody levels were elevated on at least one occasion, whereas 5,567 were antibody-negative during the observation period. Patients with thyroid antibodies were significantly older (P < 0.001), had a longer duration of diabetes (P < 0.001), and developed diabetes later in life (P < 0.001) than those without antibodies. A total of 63% of patients with positive antibodies were girls, compared with 45% of patients without antibodies (P < 0.001). The prevalence of significant thyroid antibody titers increased with increasing age; the highest prevalence was in the 15- to 20-year age group (anti-TPO: 16.9%, P < 0.001; anti-TG: 12.8%, P < 0.001). Thyroid-stimulating hormone (TSH) levels were higher in patients with thyroid autoimmunity (3.34 microU/ml, range 0.0-615.0 microU/ml) than in control subjects (1.84 microU/ml, range 0.0-149.0 microU/ml) (P < 0.001). Even higher TSH levels were observed in patients with both anti-TPO and anti-TG (4.55 microU/ml, range 0.0-197.0 microU/ml).

CONCLUSIONS

Thyroid autoimmunity seems to be particularly common in girls with diabetes during the second decade of life and may be associated with elevated TSH levels, indicating subclinical hypothyroidism.