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

Correlation between estradiol-to-testosterone ratio and thyroid peroxidase antibody positivity in men with treatment-naïve primary hypothyroidism or euthyroidism

Objective

Thyroid diseases pose a substantial socioeconomic burden globally. The aim of this study was to evaluate the correlation between estradiol-to-testosterone (E2/T) ratio and thyroid peroxidase antibody (TPOAb) positivity in male patients with hypothyroidism or euthyroidism.

Subjects and methods

Cross-sectional observational study including 115 male patients with hypothyroidism or euthyroidism. The patients were divided into two groups based on positive or negative TPOAb results, with TPOAb positivity defined by a serum TPOAb value ≥ 35 IU/mL.

Results

Patients with positive TPOAbs, compared with those with negative TPOAbs, had a higher prevalence of goiter and obesity and higher levels of total cholesterol, triglycerides, and low-density lipoprotein (LDL) cholesterol. The median estradiol level was higher, and the median total testosterone and sex-hormone binding globulin (SHBG) levels were lower in the TPOAb-positive versus the TPOAb-negative group (p < 0.001). In subgroup analysis including only patients with hypothyroidism (n = 80), the median E2/T ratio was higher in the TPOAb-positive group (p = 0.016). The prevalence of TPOAb positivity increased with the increase in E2/T ratio quartiles, from 37.9% in the lowest quartile to 96.2% in the highest quartile (p value for trend across all quartiles < 0.001). On adjusted multivariate analysis, the E2/T ratio emerged as an independent predictor of TPOAb positivity. An E2/T ratio cutoff value of 6.565 x10-3 demonstrated the best diagnostic accuracy, with a sensitivity of 78.2% and specificity of 67.6%.

Conclusion

The present study provides insights into the role of the E2/T ratio as a predictor of thyroid disorders.

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.

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.

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.

Oxidative status in children and adolescents with autoimmune thyroiditis

Oxidative status in autoimmune thyroiditis (AIT) has not been investigated previously in children and adolescents. We investigated oxidant and antioxidant systems in a cohort of Egyptian children and adolescents with AIT to explore these as biomarkers of autoimmunity and thyroid function. Our case control study included 32 children with AIT and 32 healthy subjects with matching age and sex as a control group. After a thorough history and physical examination, a thyroid ultrasound, measurements of thyroid-stimulating hormone (TSH), free thyroxin (FT4), antithyroid peroxidase antibodies (TPOAb), and antithyroglobulin antibody were done with assessment of malondialdehyde (MDA) and total antioxidant capacity (TAC) levels as oxidative stress markers. Overt hypothyroidism was detected in 23/32, while subclinical hypothyroidism was detected in nine of the 32 studied patients. MDA levels were significantly elevated, while TAC levels were significantly decreased in AIT patients compared with healthy controls. The difference was more evident in patients with overt hypothyroidism than those with subclinical hypothyroidism. We also observed significant positive correlations of TPOAb levels with age, TSH, MDA, and thyroid volume, finding a negative correlation with TAC and FT4. In conclusion, the high serum MDA and lower TAC levels in patients with AIT and the correlation of thyroid antibodies with biomarkers of oxidative stress may reflect the role of autoimmunity in the development of oxidative stress. Future studies are needed for evaluation of antioxidant therapy for AIT patients. ClinicalTrials.gov Identifier NCT02318160. https://clinicaltrials.gov/ct2/show/NCT02318160 .

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.

Insulin resistance in hypothyroid patients under Levothyroxine therapy: a comparison between those with and without thyroid autoimmunity

Background

A chronic inflammation resulting from an imbalance between pro-inflammatory and anti-inflammatory cytokines in Hashimoto’s thyroiditis (HT) might be responsible for IR in hypothyroidism. This study was performed to investigate a probable association between autoimmune background of hypothyroidism and IR.

Methods

In this clinical study, 63 subjects with Hashimoto’s thyroiditis and 49 subjects with post-ablation hypothyroidism were enrolled. All the participants were euthyroid for more than one year through Levothyroxine therapy. Serum concentrations of Thyroid-stimulating Hormone (TSH), Free Thyroxin (FT4, FT3), Anti-Thyroid Peroxidase Antibodies (Anti-TPO Abs), Total Cholesterol (TC), HDL-Cholesterol (HDL-C), Triglyceride (TG), Fasting Blood Glucose (FBG), and insulin levels were measured and Oral Glucose Tolerance Test (OGTT) was performed for all of the subjects. Participants with anti TPO levels more than 1000 IU /ml were classified as having highly positive antibodies.

Results

No significant differences regarding to plasma insulin, glucose and lipid concentration, were detected between subjects with and without Hashimoto’s thyroiditis. However, subjects with highly positive Anti TPO Abs had higher prevalence of elevated fasting insulin level than those with lower titers of Anti TPO Abs and subjects without autoimmune background (94.1% vs. 62.8% and 71.4% respectively, P = 0.05). Subjects with highly positive titers of Abs also had a lower serum HDL-c levels than the rest of the subjects (40.6 ± 2.1 vs. 47.2 ± 1.7 and 47.4 ± 1.4, P = 0.04).

Conclusions

There is no obvious association between thyroid autoimmunity and metabolic indexes of hypothyroid patients. Only patients with Ani TPO antibody levels more than 1000 IU/ml may experience higher insulin level and less HDL-c with the same BMI.

Atypical Presentation of Riedel's Thyroiditis: Multifocal Nodular Fibrosis and Resolution with Levothyroxine

BACKGROUND

Riedel's thyroiditis is characterised by chronic inflammatory invasive fibrosclerosis of the thyroid gland, surrounding structures, and extrathyroidal fibrosis. We present a case of Riedel's thyroiditis associated with nodular fibrosis of the lungs and liver.

CASE

A 40-year-old woman presented with a 3-month history of neck swelling, difficulty swallowing and breathlessness on exertion. Core biopsy of the goitre revealed dense fibrous tissue with mixed chronic inflammatory cells. A staging computed tomography scan revealed a large thyroid mass encasing the oesophagus and compressing the trachea, multiple bilateral pulmonary nodules with no evidence of lymphadenopathy, and multiple suspicious nodular lesions in the liver. A thorascopic biopsy of a lung lesion in its entirety revealed a hyalinising lung lesion with no evidence of malignancy. Following the introduction of levothyroxine replacement, symptomatic improvement occurred in parallel with improvements in imaging.

CONCLUSION

To our knowledge, this is the first description of Riedel's thyroiditis presenting with nodular extrathyroidal fibrosis, and which showed resolution following institution of levothyroxine.

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.

The association between severity of obstructive sleep apnea and prevalence of Hashimoto's thyroiditis

Obstructive sleep apnea (OSA) has long been suggested to increase the risk of development of autoimmune diseases. We investigated the prevalence of Hashimoto's thyroiditis (HT) in 245 euthyroid individuals, who were suspected of having OSA. After polysomnography, subjects were grouped according to apnea-hypopnea index (AHI) consecutively as controls (n=27F/32M, AHI<5), mild-OSA (n=22F/37M, 5≤AHI<15), moderate-OSA (n=23F/38M, 15≤AHI<30) and severe-OSA (n=30F/36M, AHI≥30). Diagnosis of HT based on thyroid ultrasound and positivity of serum anti-thyroglobulin (anti-TG) and anti-thyroid peroxidase (anti-TPO) antibodies. Hashimoto's thyroiditis was diagnosed in 32.2% of controls and in 46.8% of all OSA patients (p=0.03). Severe-OSA patients had the highest HT frequency (51.5%) compared to controls (p=0.02), mild-OSA (42.3%, p=0.03) and moderate-OSA (45.9%, p=0.05) groups. Forty-two of control subjects (71.2%) were negative for both of the anti-TPO and anti-TG, whereas 99 (53.2%) of OSA subjects were positive at least for one of them (p=0.01). HT was detected in 62% of females, 29% of males (p<0.001). Severe female OSA patients had the highest HT prevalence (73.3%), while male control subjects had the lowest (18.7%) among all groups (p<0.001). There was no significant correlation between thyroid volume and severity of OSA but isthmus thickness was significantly correlated to AHI (p<0.01, r=0.22). In conclusion, OSA patients presented higher HT prevalence parallel to severity of OSA, especially among women. These results may lead to further investigations about relation between OSA and auto-immune thyroiditis and to development of screening schemas for severe-OSA patients for early diagnosis of HT before development of hypothyroidism.

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.

A retrospective study on IVF outcome in euthyroid patients with anti-thyroid antibodies: effects of levothyroxine, acetyl-salicylic acid and prednisolone adjuvant treatments

BACKGROUND

Anti-thyroid antibodies (ATA), even if not associated with thyroid dysfunction, are suspected to cause poorer outcome of in vitro fertilization (IVF).

METHODS

We retrospectively analyzed: (a) the prevalence of ATA in euthyroid infertile women, (b) IVF outcome in euthyroid, ATA+ patients, and (c) the effect of adjuvant treatments (levothyroxine alone or associated with acetylsalicylic acid and prednisolone) on IVF results in ATA+ patients. One hundred twenty-nine euthyroid, ATA+ women undergoing IVF were compared with 200 matched, ATA-controls. During IVF cycle, 38 ATA+ patients did not take any adjuvant treatment, 55 received levothyroxin (LT), and 38 received LT +acetylsalicylic acid (ASA)+prednisolone (P).

RESULTS

The prevalence of ATA among euthyroid, infertile patients was 10.5%, similar to the one reported in euthyroid women between 18 and 45 years. ATA+ patients who did not receive any adjuvant treatment showed significantly poorer ovarian responsiveness to stimulation and IVF results than controls. ATA+ patients receiving LT responded better to ovarian stimulation, but had IVF results as poor as untreated ATA+ women. Patients receiving LT+ASA+P had significantly higher pregnancy and implantation rates than untreated ATA+ patients (PR/ET 25.6% and IR 17.7% vs. PR/ET 7.5% and IR 4.7%, respectively), and overall IVF results comparable to patients without ATA (PR/ET 32.8% and IR 19%).

CONCLUSION

These observations suggest that euthyroid ATA+ patients undergoing IVF could have better outcome if given LT+ASA+P as adjuvant treatment. This hypothesis must be verified in further randomized, prospective studies.

Clinical evolution of autoimmune thyroiditis in children and adolescents

BACKGROUND

Few studies have addressed the clinical evolution of autoimmune thyroiditis (AIT) occurring in childhood and scant data are available on the role of thyroid ultrasonography. We aimed to evaluate the natural history of AIT diagnosed in children and adolescents and to assess the possible prognostic role of ultrasonography.

METHODS

Retrospective case series prospectively followed up for a further 3-year period.

RESULTS

A series of 23 patients with AIT, diagnosed before 18 years of age from 1994 to 2004, was further followed up from 2005 to 2007 with clinical, laboratory, and ultrasound evaluation. Hypothyroid patients were treated with levothyroxine (LT(4)), while euthyroid patients were left untreated. Patients with subclinical hypothyroidism were also evaluated 40 days after LT(4) withdrawal. At diagnosis seven patients were euthyroid, 14 with subclinical hypothyroidism, and two with overt hypothyroidism. Median follow-up was 4.7 years. At last follow-up visit, none of the seven euthyroid patients had developed hypothyroidism. Three of the 14 patients with subclinical hypothyroidism recovered a normal thyroid function while only one patient showed an increase in TSH level. By serological screening we identified three patients with other autoimmune disorders.

CONCLUSIONS

In young patients with normal or mildly increased TSH levels and minimal echographic changes, AIT may remain stationary for years. In fact, patients with subclinical hypothyroidism recover a normal thyroid function in approximately 20% of cases. In patients with subclinical hypothyroidism and goiter, LT(4) therapy may induce thyroid size reduction. Screening for other autoimmune disorders is useful to identify patients that need further diagnostic assessment.

Differential presentation for children with autoimmune thyroiditis discovered because of symptom development or screening

AIM

To determine clinical and laboratory differences at presentation of autoimmune thyroiditis (AIT) among children with AIT discovered due to symptom development and those discovered by screening due to having increased risk of AIT from an underlying disorder.

STUDY DESIGN

Retrospective chart review of patients with AIT seen in an academic pediatric endocrinology practice. We identified 252 children with AIT: 160 diagnosed following symptom development (the 'symptoms' group), 74 with AIT found by screening (the 'screening' group) and 18 with increased risk who were tested because they developed symptoms (the 'symptoms + screening' group).

RESULTS

We found that compared to the 'symptoms' group, individuals in the 'screening' group were younger and had a lower proportion of females. In addition, the 'screening' group were more likely to be euthyroid (60% of 'screening' vs 19% for 'symptoms') and less likely to have overt hypothyroidism (7% 'screening' vs 45% 'symptoms'). The 'screening' group were also less likely to have multiple symptoms of hypothyroidism noted in retrospect.

CONCLUSIONS

Screening for AIT identifies patients at an earlier stage of AIT. Additionally, the association of symptoms with subclinical hypothyroidism may lend support to initiating levothyroxine treatment for symptomatic children with mild TSH elevations.

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.

Association between the severity of Hashimoto's disease and the functional +874A/T polymorphism in the interferon-gamma gene

CD8+ CD25+-activated cytotoxic T cells and anti-thyroglobulin antibodies (TgAb) are independently involved in the severity of Hashimoto's disease (HD). Interferon gamma (IFN-gamma) activates cytotoxic T cells. To evaluate the hypothesis that the functional +874A/T polymorphism in the gene encoding IFN-gamma is associated with the severity of HD, we examined the frequencies of this polymorphism in 34 HD patients who developed hypothyroidism (severe HD); 22 untreated, euthyroid HD patients (mild HD); 49 patients with intractable Graves' disease (GD); 16 GD patients in remission; and 57 healthy volunteers. Frequency of the +874T allele, which is associated with high IFN-gamma production, was higher in patients with severe HD than in those with mild HD (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.0-12.4; p = 0.047), but there was no difference in the frequency between GD patients. The difference in the frequency of +874T was observed in the subset of patients with HD negative for TgAb (OR, 8.4; 95% CI, 1.2-57.3; p = 0.029) but not in the subset of patients with HD positive for TgAb. Our data indicate that the +874A/T polymorphism in the IFN-gamma gene is associated with severity of HD.