Serum negative autoimmune thyroiditis displays a milder clinical picture compared with classic Hashimoto's thyroiditis

Is There a Link between Thyroid Peroxidase Gene Promoter Polymorphisms and Autoimmune Thyroiditis in the Polish Population?

(1) Autoimmune thyroiditis (AIT) is the most common cause of primary hypothyroidism and one of the most frequent organ-specific autoimmune diseases. Its pathogenesis is polygenic and still requires further research. The aim of the study was to assess, for the first time in the Caucasian population, the role of selected TPO gene promoter polymorphisms (rs2071399 G/A, rs2071400C/T, rs2071402 A/G, and rs2071403 A/G) in the development of AIT. A total of 237 patients diagnosed with AIT and 130 healthy controls were genotyped for four TPO gene polymorphisms, and the results were statistically analyzed to check for the role of these polymorphisms. There were no significant differences in the genotype and allele frequencies of the studied TPO gene promoter polymorphisms between patients and controls (p > 0.05). The haplotype distribution (rs2071400-rs2071402-rs2071403) between the two studied groups was similar for the most common variants (CGA, CAG, TGG). Only a rare haplotype (CGG) occurred more frequently among patients compared to controls (p = 0.04). The studied TPO gene promoter polymorphisms did not show an association with susceptibility to AIT in the Caucasian Polish population, contrary to the results in Japanese patients.

Structural and functional differences in auto-antibody positive compared to auto-antibody negative hypothyroid patients with chronic thyroiditis

Most primary hypothyroidism in adults is caused by chronic thyroiditis. Autoantibodies such as anti-thyroglobulin antibody (TgAb) and anti-thyroid peroxidase antibody (TPOAb) are involved in the pathogenesis of chronic thyroiditis. On the other hand, the clinical features of antibody-negative hypothyroidism are not clear. In this study, we aimed to determine the prevalence of thyroid-related autoantibodies in patients with primary hypothyroidism and to evaluate the differences in thyroid structure between antibody-positive and antibody-negative hypothyroidism. Among 804 patients who attended Kawasaki Medical School Hospital for thyroid hormone abnormalities or thyroid gland enlargement between January 1, 2010 and December 31, 2021, 237 patients with primary hypothyroidism who underwent thyroid antibody measurement and thyroid ultrasound examination were included. Participants were divided into groups according to antibody positivity/negativity, and differences in antibody positivity and thyroid structure were evaluated. In this study, 34.6% of patients had antibody-negative hypothyroidism. The positive rate of each antibody was 62.0% for TgAb and 49.4% for TPOAb. The participants with antibody-positive hypothyroidism had significantly larger thyroid gland on thyroid ultrasound examination (p < 0.05). Thyroid-stimulating hormone was significantly higher in participants with antibody-positive compared to antibody-negative hypothyroidism. The present study reveals a positive rate of thyroid-related autoantibodies in patients with hypothyroidism and the differences in thyroid structure between patients with and without antibodies. This study clearly show that the prevalence of antibody-negative chronic thyroiditis is quite high among hypothyroid patients, although this point needs confirmation by further investigations. The data in this study would be useful for the treatment of antibody-negative hypothyroid patients.

AI-Assisted Ultrasound for the Early Diagnosis of Antibody-Negative Autoimmune Thyroiditis

The prevalence of antibody-negative chronic autoimmune thyroiditis (SN-CAT) is increasing. The early diagnosis of SN-CAT can effectively prevent its further development. Thyroid ultrasound can diagnose autoimmune thyroiditis and predict hypothyroidism. Primary hypothyroidism with a hypoechoic pattern suggested by thyroid ultrasound and negative thyroid serum antibodies is the main basis for the diagnosis of SN-CAT. However, for early SN-CAT, only hypoechoic thyroid changes and serological antibodies are currently available. This study explored how to achieve an accurate and early diagnosis of SN-CAT and prevent the development of SN-CAT combined with hypothyroidism. The diagnosis of a hypoechoic thyroid by artificial intelligence is expected to be a breakthrough in the accurate diagnosis of SN-CAT.

Thyroid autoantibodies

Thyroid-stimulating hormone (TSH) receptor antibody (TSH-R-Ab or TRAb) testing plays a pivotal role in arriving at the aetiological diagnosis in patients with thyrotoxicosis. A positive test establishes the diagnosis of Graves' disease (GD) while a negative result in conjunction with imaging studies supports other possible aetiologies. In patients with GD, TRAb levels at diagnosis and at the time of withdrawal of antithyroid drugs can identify patients who are unlikely to achieve remission and guide clinical management decisions. We provide an algorithm that incorporates TRAb in the decision-making process for the management of thyrotoxicosis. The utility of TRAb in predicting the risk of fetal and neonatal thyroid dysfunction is established and widely accepted in guidelines. TRAb may also help in the diagnosis of Graves' orbitopathy, especially in euthyroid or hypothyroid patients and its role in guiding its management is evolving as a useful adjunct to the clinical parameters used in making therapeutic decisions.Anti-thyroid peroxidase antibodies (TPOAb) and anti-thyroglobulin antibodies (TgAb) indicate thyroid autoimmunity. The most common use of TPOAb is to identify patients at a higher risk of progression to treatment-requiring hypothyroidism. They also aid the diagnosis of immune thyroiditis and Hashimoto's encephalopathy. Thyroglobulin measurement is used to help guide differentiated thyroid cancer treatment. TgAb is used as an accompanying test with thyroglobulin measurement as its presence can interfere with the thyroglobulin assay. A negative TgAb result reduces the likelihood of, but does not exclude, interference with thyroglobulin assay.

High frequency of autoimmune thyroiditis in euthyroid girls with premature adrenarche

Objective

The purpose of this study was to investigate the frequency of autoimmune thyroiditis (AT) among euthyroid prepubertal girls presenting with premature adrenarche (PA). We also aimed to identify the clinical, metabolic, and endocrine profile of girls with AT and concurrent PA and compare them to girls with AT without PA, PA alone and healthy controls.

Methods

Ninety-one prepubertal girls aged 5-10 years, who attended our department for AT, PA and normal variants of growth and puberty were recruited for the study: 73 girls had PA, 6 AT without PA and 12 were referred for investigation of growth. All girls underwent clinical examination, detailed biochemical and hormonal screen. Standard dose Synachten stimulation test (SDSST) and oral glucose tolerance test (OGTT) were performed in all girls with PA. The whole study population was divided in 4 groups: Group PA-/AT+ included 6 girls with AT without PA; Group PA+/AT- PA subjects without AT; Group PA+/AT+ girls with PA and concomitant AT; Group PA-/AT- twelve healthy girls without PA nor AT (controls).

Results

Among 73 girls presenting with PA 19 had AT (26%). BMI, systolic blood pressure (SBP) and the presence of goiter significantly differed between the four groups (p = 0.016, p = 0.022 and p < 0.001, respectively). When comparing hormonal parameters among the four groups significant differences were found in leptin (p = 0.007), TSH (p = 0.044), anti-TPO (p = 0.002), anti-TG (p = 0.044), IGF-BP1 (p = 0.006), Δ4-Α (p = 0.01), DHEA-S (p = <0.001), IGF-1 (p = 0.012) and IGF-BP3 (p = 0.049) levels. TSH levels were significantly higher in Group PA+/AT+ compared to PA+/AT- and PA-/AT- (p = 0.043 and p = 0.016, respectively). Moreover, girls with AT (Groups PA-/AT+ and PA+/AT+) had higher TSH levels than those in Group PA+/AT- (p = 0.025). Girls in Group PA+/AT + showed higher cortisol response at 60 min post-SDSST than girls in Group PA+/AT- (p = 0.035). During the OGTT, insulin concentrations at 60 min were significantly higher in Group PA+/AT + compared to Group PA+/AT- (p = 0.042).

Conclusion

A high frequency of AT among euthyroid prepubertal girls with PA was observed. The combination of PA with AT even in euthyroid state may be associated with a greater degree of insulin resistance, than PA alone.

Severe Hypothyroidism and Large Goiter due to Iodine Deficiency in an Adolescent Male in the United States: A Case Report and Review of the Literature

Acquired hypothyroidism due to iodine deficiency is extremely rare in the United States due to the introduction of table salt iodization in the 1920s (Leung et al., 2012). We present the case of an adolescent male with a history of mild autism spectrum disorder and an extremely restrictive diet who was found to have iodine deficiency as the etiology for his rapidly enlarging goiter and antibody-negative hypothyroidism. Thyroid-stimulating hormone (TSH) was 416 μIU/mL (0.350–5.500 μIU/mL), free thyroxine (T4) was <0.1 ng/dL (0.80–1.80 ng/dL), and triiodothyronine (T3) was 41 ng/dL (82–213 mg/dL) at diagnosis. The patient's 24-hour urinary iodine was undetectable. He was started on iodine supplementation with rapid visible improvement of goiter within two weeks and normalization of thyroid function tests within four weeks. Thorough dietary history and nutritional screening are important in cases of acquired hypothyroidism and/or goiter. Alternatively, diets that are low in iodized salt, dairy, bread, and seafood should raise concern for iodine deficiency, and patients with suspected or proven iodine deficiency should be screened for hypothyroidism.

Seronegative autoimmune diseases: A challenging diagnosis

Autoimmune diseases (AID) are increasingly prevalent conditions which comprise more than 100 distinct clinical entities that are responsible for a great disease burden worldwide. The early recognition of these diseases is key for preventing their complications and for tailoring proper management. In most cases, autoantibodies, regardless of their potential pathogenetic role, can be detected in the serum of patients with AID, helping clinicians in making a definitive diagnosis and allowing screening strategies for early -and sometimes pre-clinical- diagnosis. Despite their undoubted crucial role, in a minority of cases, patients with AID may not show any autoantibody, a condition that is referred to as seronegative AID. Suboptimal accuracy of the available laboratory tests, antibody absorption, immunosuppressive therapy, immunodeficiencies, antigen exhaustion, and immunosenescence are the main possible determinants of seronegative AID. Indeed, in seronegative AID, the diagnosis is more challenging and must rely on clinical features and on other available tests, often including histopathological evaluation and radiological diagnostic tests. In this review, we critically dissect, in a narrative fashion, the possible causes of seronegativity, as well as the diagnostic and management implications, in several AID including autoimmune gastritis, celiac disease, autoimmune liver disease, rheumatoid arthritis, autoimmune encephalitis, myasthenia gravis, Sjögren's syndrome, antiphospholipid syndrome, and autoimmune thyroid diseases.

Seronegative phenotype in a pediatric population with Hashimoto's thyroiditis

PURPOSE

The aim was to verify in a pediatric population with Hashimoto's thyroiditis whether there is a relationship between antithyroid antibodies and inflammatory status on thyroid ultrasound and thyroid function.

SUBJECTS AND METHODS

A total of 154 children and adolescents, aged 4 to 18 years, diagnosed with Hashimoto's thyroiditis with normal body weight were followed up for 1 year.

RESULTS

Patients with only antiperoxidase antibodies presented with higher TSH levels than subjects with only antithyroglobulin antibodies (p 0.027) but with similar FT4 levels and thyroid score. Prevalence of seronegative Hashimoto's thyroiditis in this cohort was 12.3% (19/154). At diagnosis, the seronegative group presented with lower prevalence of overt hypothyroidism, symptoms of hypothyroidism, and thyroid score, meaning less severe thyroid involvement. In contrast, similar TSH and FT4 values were found at diagnosis and during follow-up in both the seronegative and seropositive groups. A comparison between patients with seronegative Hashimoto's thyroiditis and an overweight/obese antibody-negative population, who presented superimposable altered parenchymal pattern on thyroid ultrasound without circulating antithyroid antibodies, presented similar clinical data.

CONCLUSION

We report for the first time in the literature that seronegative Hashimoto's thyroiditis in the pediatric age group has a less severe pattern. The seronegative group presents similar characteristics to those of overweight/obese children and adolescents with ultrasound changes, but, according to the established knowledge, the latter condition is reversible and does not need follow-up examinations.

Mistaken Identity: The Role of Autoantibodies in Endocrine Disease

BACKGROUND

Autoimmune endocrine diseases can be thought of as a case of mistaken identity. The immune system mistakenly attacks one's own cells, as if they were foreign, which typically results in endocrine gland hypofunction and inadequate hormone production. Type 1 diabetes mellitus and autoimmune thyroid disorders (Hashimoto and Graves diseases) are the most common autoimmune endocrine disorders, while conditions such as Addison disease are encountered less frequently. Autoantibody production can precede clinical presentation, and their measurement may aid verification of an autoimmune process and guide appropriate treatment modalities.

CONTENT

In this review, we discuss type 1 diabetes mellitus, autoimmune thyroid disorders, and Addison disease, emphasizing their associated autoantibodies and methods for clinical detection. We will also discuss efforts to standardize measurement of autoantibodies.

CONCLUSIONS

Autoimmune endocrine disease progression may take months to years and detection of associated autoantibodies may precede clinical onset of disease. Although detection of autoantibodies is not necessary for diagnosis, they may be useful to verify an autoimmune process.

Precision Medicine in Autoimmune Thyroiditis and Hypothyroidism

Autoimmune thyroid diseases (AITD) are T-cell-mediated organ specific autoimmune disorders, deriving from an altered response of the immune system that leads to the immune attack to the thyroid. Hashimoto’s thyroiditis (HT) and Graves’ disease (GD) are the two principal AITD clinical presentations. Hypothyroidism and thyrotoxicosis are, respectively, the clinical hallmarks of HT and GD. Patients with autoimmune thyroiditis are treated daily with synthetic L-thyroxine (L-T4) at the dose of 1.5–1.7 μg/kg. Various L-T4 formulations are commercially available (tablet, liquid solution, or soft gel capsule). L-T4 in tablets is generally prescribed to treat hypothyroidism, whereas the liquid formulation, or soft gel capsules, can be administered in hypothyroid patients in case of malabsorption or in patients in therapy with drugs interfering with L-T4 absorption. Furthermore, myoinositol has a crucial role in thyroid autoimmunity and function. Clinical studies reported a significant decline in TSH and antithyroid autoantibodies levels after treatment with myoinositol + selenium in patients with subclinical hypothyroidism and autoimmune thyroiditis. Moreover, thyroidectomy can be rarely recommended in patients with autoimmune thyroiditis, with cosmetic reasons for a goiter, or with important signs or symptoms of local compression, or nodular disease with a “suspicious” cytology for malignancy. Furthermore, a recent randomized trial suggested that total thyroidectomy can improve quality of life and fatigue, while medical therapy did not. In this review, we overview currently available evidence in personalized medicine in patients with autoimmune thyroiditis and hypothyroidism. Further research is needed in larger population to investigate the effect of these new treatments on quality of life.

Association between anti-thyroid antibodies and quality of life in patients with Hashimoto thyroiditis: a systematic review and meta-analysis

OBJECTIVE

The aim of this review was to evaluate the association between anti-thyroid antibodies and quality of life in people with euthyroid Hashimoto thyroiditis.

INTRODUCTION

Patients with Hashimoto thyroiditis report symptom distress more often than those with non-autoimmune thyroid disorders. Therefore, anti-thyroid antibodies may be related to decreased quality of life in persons with Hashimoto thyroiditis. The etiology of lingering symptoms, even in euthyroidism, remains unknown. The relationship between anti-thyroid antibodies and quality of life for people with Hashimoto thyroiditis has not been evaluated in a systematic review.

INCLUSION CRITERIA

The participants were males and females at least 12 years of age, in any country, with Hashimoto thyroiditis. Participants not in a euthyroid state were excluded from this review. In this review, the exposure was the presence of anti-thyroid antibodies and the primary outcome was quality of life as measured by a validated scale.

METHODS

A three-step search strategy was implemented with an initial search of PubMed and CINAHL. A comprehensive database search using all identified keywords and index terms was undertaken in March 2019 for relevant published literature, gray literature, and clinical trial registries. The final updates to the search strategies were conducted in December 2019. The search was limited to studies published in English after 1956. Two independent reviewers completed screening for inclusion and utilized the recommended JBI approach to critical appraisal, study selection, data extraction, and data synthesis. The findings are presented in a meta-analysis and in a narrative synthesis, which includes tables and figures.

RESULTS

All 13 studies had high methodological quality. Four studies found a significant correlation (P < 0.05) between the presence of anti-thyroid antibodies and quality of life. A fifth study found a significant correlation (P < 0.001) between higher antibody levels and quality of life. A meta-analysis was conducted using two cross-sectional studies, which revealed that the summative small effect size was statistically significant and suggested a lower quality of life in antibody-positive patients. Due to the heterogeneity of the studies, a narrative synthesis was conducted for the three secondary outcomes: symptom distress, executive function, and mental health. Three studies found a statistically significant (P < 0.05) correlation between symptom distress and antibodies, two studies found a statistically significant (P < 0.05) association between executive function and antibodies, and all but one study found a statistically significant (P < 0.05) relationship between mental health and antibodies.

CONCLUSIONS

The findings in this review did not reveal a definitive relationship between antibodies and quality of life. However, our meta-analysis suggested a link between anti-thyroid antibodies and decreased quality of life in euthyroid children and adults. Though not conclusive, poor mental health and symptom distress may be associated with anti-thyroid antibodies. Therefore, it may be beneficial to periodically evaluate the quality of life and mental health in euthyroid patients with positive antibodies. It is unlikely that antibodies and executive functions are related. The studies and our review's limitations require replication of findings to confirm a connection between antibodies, quality of life, and the secondary outcomes. Future research should continue to evaluate the relationship between anti-thyroid antibodies and the quality of life in individuals with euthyroid Hashimoto thyroiditis.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42018084663.

Compared with classic Hashimoto's thyroiditis, chronic autoimmune serum-negative thyroiditis requires a lower substitution dose of L-thyroxine to correct hypothyroidism

PURPOSE

Serum-negative-chronic-autoimmune-thyroiditis (SN-CAT) is considered a milder variant of classic Hashimoto's thyroiditis (CHT). However, its prevalence remains unknown and it is still unclear whether SN-CAT behaves differently in terms of L-thyroxine (LT4) substitution treatment of hypothyroidism. Aims of this study were to estimate the prevalence of SN-CAT in a large series of hypothyroid patients and to compare LT4 requirements in hypothyroid patients with SN-CAT and CHT.

METHODS

Five-hundred-eighty-one consecutive patients with primary-autoimmune-hypothyroidism were enrolled in a cross-sectional study. LT4 requirements and thyroid-volume changes were longitudinally evaluated in 49 hypothyroid patients with SN-CAT and in 98 sex and age-matched hypothyroid patients with CHT.

RESULTS

In our series the prevalence of SN-CAT was 20.8%. At diagnosis, patients in the CHT and SN-CAT groups had similar male/female ratio, age and BMI, while serum TSH and thyroid-volume were significantly greater in the CHT group. In the longitudinal study, during a follow-up of 8.9 ± 4.6 years, 8 out of 49 (16.3%) SN-CAT patients developed positive tests for of circulating TPO-Ab and/or Tg-Ab. Thyroid-volume significantly decreased in CHT patients, but not in those with SN-CAT. The maximum daily substitution dose of LT4 was smaller in SN-CAT patients as compared with the CHT ones. Multivariate analysis showed that age, BMI, basal TSH and thyroid antibody status independently and significantly predicted the maximum daily substitution dose of LT4.

CONCLUSIONS

SN-CAT accounts for a significant proportion of patients with autoimmune hypothyroidism. Compared with hypothyroid patients diagnosed with CHT, the SN-CAT ones require smaller doses of LT4 to correct their hypothyroidism.

Clinical features may help to identify children and adolescents with greatest risk for thyroid nodules

BACKGROUND

Thyroid nodules (TN) are detected in a small number of asymptomatic children and adolescents but are more frequently malignant (22-26%) than in adults leading some clinicians to perform thyroid ultrasound (US) for all children with goiter or autoimmune thyroiditis (AIT). Our study was designed to determine if suspicious clinical features predict the presence of TN in children with goiter or AIT so that US could be performed on those at highest risk.

METHODS

This was a retrospective review of 223 children and adolescents with goiter or AIT evaluated at a single institution. US was not performed on all patients. It is our practice to define glands that are large, firm, or nodular to palpation as "suspicious". Suspicious glands were interrogated by US and if TN was confirmed, this was further evaluated by fine-needle aspiration followed by surgery if indicated.

RESULTS

The median age was 12.9 years with 74.4% female. TN were confirmed by US in 16.6% of all patients but only 4.8% of those with AIT. By univariate analysis, TN were more common in those with family history of TN or differentiated thyroid carcinoma (DTC), thyroid asymmetry, and lower thyrotropin (TSH) levels. Differentiated thyroid carcinoma (DTC) was identified in 10.8% of TN and 1.8% of all patients. Firmness was significantly more common in patients with DTC (p = 0.0013).

CONCLUSION

TN were less common in those with AIT than reported in previous studies, suggesting that clinical features might fail to identify the majority of TN in patients with AIT. However, patients with asymmetric thyroid and a family history of TN or DTC have greatest risk for TN.

Quantitative Color Doppler Ultrasonography Measurement of Thyroid Blood Flow in Patients with Graves' Disease

BACKGROUND

Graves' Disease is an autoimmune disorder characterized by increased levels of thyroid hormones correlated with increased thyroid blood flow. Thyroid scintigraphy is an important and conventional method. However, it has limited accessibility, has ionizing radiation, and is expensive.

OBJECTIVES

To investigate the thyroid blood flow in patients with Graves' Disease by color Doppler Ultrasonography and a newly developed software Color Quantification.

METHODS

Forty-one consecutive subjects with GD and 41 healthy controls were enrolled. Color Doppler ultrasonography parameters of the thyroid arteries and Color Quantification values of the gland were measured by a radiologist. The correlations between thyroid blood flow parameters, levels of 99mTechnetium pertechnetate uptake, thyrotropin, and free thyroxine were evaluated. The diagnostic performances of these parameters were investigated.

RESULTS

The peak systolic-end diastolic velocities of thyroid arteries and Color Quantification values were increased in the study group (p < 0.05 for all). We observed negative correlations between thyrotropin levels and peak-systolic and end-diastolic velocities of superior thyroid arteries and Color Quantification values. There were positive correlations between 99mTechnetium uptake levels and thyroid blood flow parameters (p < 0.05 for all). In the diagnostic performance of thyroid blood flow parameters, we observed utilities significantly in peak-systolic and end-diastolic velocities of thyroid arteries and Color Quantification values (p < 0.05 for all).

CONCLUSION

The increased peak-systolic and end-diastolic velocities of thyroid arteries, and increased Color Quantification values might be helpful in the diagnosis of Graves' Disease.

Infliximab Therapy Could Decrease the Risk of the Development of Thyroid Disorders in Pediatric Patients With Crohn's Disease

Autoimmune diseases, including autoimmune thyroid diseases (AITDs), may be associated with Crohn's disease (CD). Taking into consideration the role of tumor necrosis factor alpha (TNF-alpha) in the immune-mediated inflammation that underlies both diseases, we evaluated an ultrasound of thyroid gland in pediatric CD patients, naïve, and treated with infliximab (IFX), an anti-TNF-alpha antibody, to assess the risk for AITD and evaluated the usefulness of ultrasonography to diagnose AITD in patients with CD. Sixty-one patients with CD were enrolled in the study, including 36 patients (mean age 14.5 ± 3.5 years) treated with IFX (IFX group) for a mean of 13.9 ± 16.6 months and 25 patients (mean age 14.7 ± 2.3 years) who never received anti-TNF-alpha therapy (control group). An ultrasound examination of the thyroid gland was performed; thyroid function tests and thyroid antibodies were assessed. We found 10-times higher prevalence of decreased thyroid echogenicity in CD and IFX-naive patients compared to IFX-treated group [a significant reduction in thyroid echogenicity in 1/36 (2.8%) patients receiving IFX compared to 7/25 (28%) patients naive to biologic therapy]. The latter showed significantly lower thyroid-stimulating hormone (TSH) levels (p = 0.034) and higher levels of thyroid antibodies (p = 0.042) in comparison to control. Our data suggest the protective role of IFX therapy in the development of thyroid disorders and indicate the usefulness of thyroid ultrasound to identify the risk of probable AITD in pediatric patients with CD.

Thyro-entero-gastric autoimmunity: Pathophysiology and implications for patient management

The association between autoimmune atrophic gastritis and thyroid disorders has been observed since the early 1960s and the expression "thyrogastric syndrome" was coined to indicate the presence of thyroid autoantibodies or autoimmune thyroid disease in patients with pernicious anemia, a late clinical stage of autoimmune atrophic gastritis. More recently, it was confirmed that autoimmune thyroid disorders, in particular Hashimoto's thyroiditis, may be frequently associated with other organ-specific, immune-mediated disorders, such as autoimmune atrophic gastritis or celiac disease. The association of Hashimoto's thyroiditis with autoimmune atrophic gastritis or celiac disease in adult patients is currently considered part of the polyglandular autoimmune syndromes which include several autoimmune disorders associated with an autoaggressive impairment of endocrine glands. From a clinical point of view, the thyro-entero-gastric autoimmunity may lead to potentially serious consequences like anemia, micronutrients deficiencies, and drugs malabsorption, as well as to an increased risk for malignancies. These alterations may frequently present in an underhand manner, with consequent diagnostic and treatment delays. Many aspects of the association between thyroid, gastric and intestinal autoimmune diseases still await clarification. The present review focuses on the embryological, genetic and pathophysiological aspects of thyro-entero-gastric autoimmunity. In particular, the current diagnostic criteria of autoimmune thyroid disease, autoimmune atrophic gastritis, and celiac disease are reviewed, along with the evidences for their association in poly-autoimmunity syndromes. The benefits of proactive screening of autoimmune thyroid disorders in patients with autoimmune gastritis or enteropathy and viceversa are also discussed.

Improvement of Chronic Idiopathic Urticaria With Levothyroxine: A Case Report and Review of Literature

There is an increased association between chronic urticaria (CU) and thyroid autoantibodies. We presented a case of a patient suffering from CU and newly diagnosed Hashimoto’s thyroiditis in which levothyroxine therapy completely resolved the symptoms of urticaria. A 58-year-old female with a past medical history of recurrent urticaria presented with complaints of fatigue and weight gain. Laboratory investigations showed a high thyroid stimulating hormone (TSH) level and a low free thyroxine (T4) level. She had elevated levels of antithyroid peroxidase (anti-TPO) and anti-thyroglobulin antibodies (anti-TG). She was diagnosed as a case of Hashimoto's thyroiditis and started on levothyroxine therapy. She noticed that her uncontrolled recurrent urticaria started to get better and after a few months of therapy, she stopped taking her topical ointments and antihistamines. The reason for the association between positive serological tests for thyroid autoimmunity and CU is unclear. The resolution of chronic urticaria with levothyroxine in our patient with Hashimoto's thyroiditis suggests a common underlying mechanism between the two pathologies.

Growth Failure and Excessive Weight Gain in a 10 Year Old Male With Obesity: Approach to Diagnosis, Management, and Treatment of Acquired Hypothyroidism

We report the case of a 10 year old male with severe obesity who presented with a 2 year history of significant growth failure and excessive weight gain that was subsequently diagnosed with serum negative Hashimoto's thyroiditis and acquired hypothyroidism. Initial investigations revealed a markedly elevated thyroid stimulating hormone (TSH) concentration >100 uIU/mL and an undetectable free thyroxine with total thyroxine 0.56 ug/dL. Thyroid antibodies were negative, however ultrasound findings were consistent with Hashimoto's thyroiditis. After treatment with levothyroxine supplementation, he had significant weight loss and marked improvement in his growth velocity. This case emphasizes the need to recognize excessive weight gain and growth failure as an initial presentation of Hashimoto's thyroiditis and highlights management and approach to treatment. Diagnosis and treatment is vital as prolonged undiagnosed hypothyroidism can result in incomplete catch up growth and compromised final adult height.

Thyroid Autoantibodies Display both "Original Antigenic Sin" and Epitope Spreading

Evidence for original antigenic sin in spontaneous thyroid autoimmunity is revealed by autoantibody interactions with immunodominant regions on thyroid autoantigens, thyroglobulin (Tg), thyroid peroxidase (TPO), and the thyrotropin receptor (TSHR) A-subunit. In contrast, antibodies induced by immunization of rabbits or mice recognize diverse epitopes. Recognition of immunodominant regions persists despite fluctuations in autoantibody levels following treatment or over time. The enhancement of spontaneously arising pathogenic TSHR antibodies in transgenic human thyrotropin receptor/NOD.H2^h4 mice by injecting a non-pathogenic form of TSHR A-subunit protein also provides evidence for original antigenic sin. From other studies, antigen presentation by B cells, not dendritic cells, is likely responsible for original antigenic sin. Recognition of restricted epitopes on the large glycosylated thyroid autoantigens (60-kDa A-subunit, 100-kDa TPO, and 600-kDa Tg) facilitates exploring the amino acid locations in the immunodominant regions. Epitope spreading has also been revealed by autoantibodies in thyroid autoimmunity. In humans, and in mice that spontaneously develop autoimmunity to all three thyroid autoantigens, autoantibodies develop first to Tg and later to TPO and the TSHR A-subunit. The pattern of intermolecular epitope spreading is related in part to the thyroidal content of Tg, TPO and TSHR A-subunit and to the molecular sizes of these proteins. Importantly, the epitope spreading pattern provides a rationale for future antigen-specific manipulation to block the development of all thyroid autoantibodies by inducing tolerance to Tg, first in the autoantigen cascade. Because of its abundance, Tg may be the autoantigen of choice to explore antigen-specific treatment, preventing the development of pathogenic TSHR antibodies.

The association between anti-thyroid antibodies and quality of life in patients with thyroid disorders: a systematic review protocol

REVIEW QUESTION

The objective of this systematic literature review is to identify the association between anti-thyroid antibodies and quality of life in patients with thyroid disorders.

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.

Autoimmunity affects health-related quality of life in patients with Hashimoto's thyroiditis

Hashimoto's thyroiditis (HT) is the most common endocrine disorder leading to hypothyroidism. HT is characterized by the presence of elevated circulating antibodies, especially anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-Tg). In our study, we aimed to reveal the effects of autoimmunity on health-related quality of life of euthyroid HT patients. Patients who were admitted to the Adnan Menderes University Outpatient Clinic were enrolled. The medical records of the patients were surveyed and their demographical data were collected. By using communication data, the patients were invited to our clinic, to inform them about our study and to fill out the health-related quality of life questionnaire. A total of 84 euthyroid HT patients older than 18 years who completed the short form-36 questionnaire, were enrolled. As all patients were euthyroid, there was a significant negative correlation between each domain score and the antibody levels, individually. Patients who had higher anti-TPO and anti-Tg levels had significantly lower quality of life domain scores (p < 0.001). There was statistically no significant correlation between the antibody levels and thyroid function tests (p > 0.05). Additionally, all dimension scores were significantly higher both in the anti-Tg and anti-TPO negative groups, indicating a better quality of life than that in the antibody positive groups. Our study revealed that higher thyroid antibody levels were negatively correlated with life quality scores. Thus, patients who had higher anti-TPO and anti-Tg levels had significantly lower quality of life domain scores. We believe that apart from hypothyroidism, a high antibody level was one of the contributing factors for the development of HT-associated symptoms, leading to a lower quality of life. Other probable contributing factors such as selenium deficiency, thyroid hormone fluctuation, and disease awareness should keep in mind.

Levothyroxine dose adjustment in hypothyroid women achieving pregnancy through IVF

OBJECTIVE

About one out of two women with primary hypothyroidism has to increase the dosage of exogenous levothyroxine (L-T4) during pregnancy. Considering the detrimental impact of IVF on thyroid function, it has been claimed but not demonstrated that L-T4 dose adjustment may be more significant in hypothyroid women who become pregnant after IVF.

DESIGN

Retrospective cohort study.

METHODS

Hypothyroid-treated women who achieved a live birth through IVF were reviewed. Women could be included if thyroid function was well compensated with L-T4 before the IVF cycle (i.e., serum TSH <2.5  mIU/l and serum free T4 within the normal range). Serum TSH and dose adjustment were evaluated at five time points during pregnancy. The trimester ranges for serum TSH considered as reference to adjust L-T4 therapy were 0.1-2.5  mIU/l for the first trimester, 0.2-3.0  mIU/l for the second trimester, and 0.3-3.0  mIU/l for the third trimester.

RESULTS

Thirty-eight women were selected. During the whole pregnancy 32 women (84%; 95% CI: 72-96%) required an increase in the dose of L-T4. In most cases (n=28), this occured within the first 5-7 weeks of gestation (74%, 95% CI: 58-85%). At 5-7 weeks of gestation, the median (interquartile range) increase of L-T4 dose for the whole cohort was 26% (0-50%). At 30-32 weeks, it was 33% (14-68%). In order to identify predictive factors of dose adjustment, we compared women who did (n=28) and did not (n=10) adjust L-T4 dosage at 5-7 weeks' gestation. Significant differences emerged for thyroid autoimmunity prevalence and for the distribution of hypothyroidism aetiology.

CONCLUSIONS

The vast majority of hypothyroid-treated women who achieve pregnancy through IVF need an increase in the L-T4 dose during gestation. This requirement tends to occur very early during gestation.