Positive Thyroglobulin Antibodies Research Articles

Effects of altitude on thyroid disorders according to Chinese three-rung, ladder-like topography: national cross-sectional study

BackgroundChinese topography appears a three-rung ladder-like distribution of decreasing elevation from northwest to southeast, which is divided by two sloping edges. Previous studies have reported that prevalence of thyroid diseases differed by altitude, and geographical factors were associated with thyroid disorders. To explore the association between three-rung ladder-like regions and thyroid disorders according to unique Chinese topographic features, we conducted an epidemiological cross-sectional study from 2015–2017 that covered all 31 mainland Chinese provinces.MethodsA total of 78,470 participants aged ≥ 18 years from a nationally representative cross-sectional study were included. Serum thyroid peroxidase antibody, thyroglobulin antibody, and thyroid-stimulating hormone levels; urine iodine concentration; and thyroid volume were measured. The three-rung ladder-like distribution of decreasing elevation from northwest to southeast in China was categorized into three topographic groups according to elevation: first ladder, > 3000 m above sea level; second ladder, descending from 3000—500 m; and third ladder, descending from 500 m to sea level. The third ladder was further divided into groups A (500–100 m) and B (< 100 m). Associations between geographic factors and thyroid disorders were assessed using linear and binary logistic regression analyses.ResultsParticipants in the first ladder group were associated with lower thyroid peroxidase (β = -4.69; P = 0.00), thyroglobulin antibody levels (β = -11.08; P = 0.01), and the largest thyroid volume (β = 1.74; P = 0.00), compared with the other groups. The second ladder group was associated with autoimmune thyroiditis (odds ratio = 1.30, 95% confidence interval [1.18–1.43]) and subclinical hypothyroidism (odds ratio = 0.61, 95%confidence interval [0.57–0.66]) (P < 0.05) compared with the first ladder group. Group A (third ladder) (500–100 m) was associated with thyroid nodules and subclinical hypothyroidism (P < 0.05). Furthermore, group B (< 100 m) was positively associated with autoimmune thyroiditis, thyroid peroxidase and thyroglobulin antibody positivity, and negatively associated with overt hypothyroidism, subclinical hypothyroidism, and goiter compared with the first ladder group(P < 0.05).ConclusionWe are the first to investigate the association between different ladder regions and thyroid disorders according to unique Chinese topographic features. The prevalence of thyroid disorders varied among the three-rung ladder-like topography groups in China, with the exception of overt hyperthyroidism.

Age-specific association between thyroid autoimmunity and hypothyroidism in Chinese adults aged over 65 years: a cross-sectional study.

The correlation between thyroid autoimmune (TAI) disease and hypothyroidism in the elderly of different ages remains unclear. This study aimed to investigate the epidemiological characteristics of hypothyroidism, including subclinical hypothyroidism (Shypo) and overt hypothyroidism (Ohypo) in those aged ≥65 years from iodine-adequate areas and reveal the correlation between TAI and hypothyroidism in the elderly of different ages. It was a cross-sectional study involving 2,443 subjects aged ≥65 years from two iodine-adequate areas in China by cluster sampling. They were assigned to the 65-69-, 70-79-, and ≥80-year-old age group. All subjects were surveyed by questionnaires and received physical examinations, laboratory testing, and thyroid ultrasound. Epidemiological characteristics of thyroid diseases in the elderly were compared among the three groups. Risk factors for hypothyroidism were predicted by binary logistic regression analysis. The median urinary iodine level was 238.70 (197.00, 273.70) μg/L. Thyroid peroxidase antibody or thyroglobulin antibody positivity (11.87%) and Shypo (9.13%) were common in the elderly. The prevalence of hypothyroidism in the elderly increases with age. TAI was a risk factor for Shypo (OR, 1.94; 95% CI, 1.35, 2.80; p < 0.01) and Ohypo (OR, 7.64; 95% CI, 3.40, 17.19; p < 0.01) in elderly Chinese. There was an age-specific correlation between TAI and hypothyroidism in the elderly. However, a significant correlation was not identified between TAI and hypothyroidism in ≥80-year-old age group (p > 0.05). Hypothyroidism, particularly Shypo, is common in the elderly from iodine-adequate areas in China. TAI serves as a risk factor for hypothyroidism in the elderly, with an age-specific correlation with hypothyroidism.

No Association of Preablation Thyroglobulin Antibody Positivity and Outcome in Pediatric Patients With Papillary Thyroid Carcinoma.

This multicenter study was designed to evaluate the relationship between preablation thyroglobulin antibody (TgAb) positivity and clinical outcomes in pediatric patients with papillary thyroid carcinoma (PTC). In the period 2005-2020, all consecutive PTC patients 18 years or younger who underwent total thyroidectomy and radioiodine ablation at 3 tertiary hospitals in southwestern China were retrospectively included. Thyroglobulin antibody was measured before remnant ablation. Tumor characteristics and long-term outcomes were compared between TgAb-positive and TgAb-negative patients. One hundred thirty-two patients were analyzed. Preablation TgAb positivity was presented in 37.1% of patients. Tumor characteristics, lymph node metastases, and median duration of follow-up were similar between TgAb-positive and -negative patients. During follow-up, the percentage of patients with either surgical reintervention for lymph node metastases (4.1% vs 4.8%, P = 1.000) or repeated 131 I therapy (14.3% vs 20.5%, P = 0.373) was similar between TgAb-positive and -negative patients. At the final follow-up visit, the rates of structural disease did not differ between the 2 groups (6.1% vs 4.8%, P = 0.710). This multicentric study highlights no association of preablation TgAb positivity and clinical outcome in pediatric patients with PTC.

Changing Iodine Status and the Incidence of Thyroid Disease in Mainland China: A Prospective 20-Year Follow-Up Study.

Background: We aimed to assess the long-term effects of the transition in iodine status on the incidence of thyroid disorders over 20 years of follow-up. Methods: The original prospective cohort study, started in 1999 (n = 3761), classified three regions in north China based on iodine status (insufficient iodine, more than adequate iodine, and excessive iodine, respectively) for 5 years. Subsequently, participants were followed for up to another 15 years to assess the long-term effects of shifts to adequate iodine on the incidence of thyroid disorders. Panshan transitioned from insufficient to adequate iodine, and Huanghua transitioned from excessive to more than adequate iodine. Both regions were compared with Zhangwu, in which iodine status changed from more than adequate to adequate iodine (from 214 to 167.2 μg/L). A cluster sampling method was used to select participants in the three regions. Participants completed questionnaires and underwent thyroid ultrasonography. Urinary iodine concentrations (UICs), serum thyroid hormone concentration, and thyroid antibodies were measured. Results: When the iodine status changed from insufficient to adequate (with the median UIC increasing from 88 to 141.9 μg/L), the incidence density of subclinical hyperthyroidism, positive thyroperoxidase antibody, positive thyroglobulin antibody (TgAb), and goiter decreased significantly (p < 0.05 for all). Additionally, the cumulative incidence of subclinical hypothyroidism was significantly lower compared with the region where the iodine status changed from being more than adequate to adequate (1.9% vs. 6.0%, p < 0.001). When the iodine status changed from excessive to more than adequate (median UIC from 634 to 266.7 μg/L), a significant decrease in the incidence density of subclinical hyperthyroidism, positive thyroid antibodies, positive TgAb, and goiter (p < 0.05 for all) were also found. However, an increase in thyroid nodule incidence density (17.26 vs. 28.25 per 1000 person-years, p < 0.001) was seen. Conclusions: The incidence of thyroid disorders (except for thyroid nodules) stabilized or decreased among adults in the three communities from year 5 to year 15 of follow-up. Appropriate iodine fortification is safe and effective over the long term. Restoring urinary iodine to appropriate levels reduces population risk for thyroid disorders.

Multi-omics profiling of papillary thyroid microcarcinoma reveals different somatic mutations and a unique transcriptomic signature

BackgroundPapillary thyroid microcarcinoma (PTMC) incidence has significantly increased, and some cases still exhibit invasive traits. The entire molecular landscape of PTMC, which can offer hints for the etiology of cancer, is currently absent.MethodsWe compared our findings with those for PTMC in the TCGA by analyzing the largest study at the current stage of whole exome sequencing and RNA-sequencing data from 64 patients with PTMC. Then, we systematically demonstrated the differences between the two PTMC subtypes based on multi-omics analyses. Additionally, we created a molecular prediction model for the PTMC subtypes and validated them among TCGA patients for individualized integrative assessment.ResultsIn addition to the presence of BRAF mutations and RET fusions in the TCGA cohort, we also discovered a new molecular signature named PTMC-inflammatory that implies a potential response to immune intervention, which is enriched with AFP mutations, IGH@-ext fusions, elevated immune-related genes, positive peroxidase antibody, and positive thyroglobulin antibody. Additionally, a molecular prediction model for the PTMC-inflammatory patients was created and validated among TCGA patients, while the prognosis for these patients is poor.ConclusionsOur findings comprehensively define the clinical and molecular features of PTMC and may inspire new therapeutic hypotheses.

Sex-Specific Effect of Thyroid Peroxidase Antibody and Thyroglobulin Antibody Exposure During Pregnancy on Preschoolers' Emotional and Behavioral Development: A Birth Cohort Study.

Background: Epidemiological and experimental studies suggest that thyroid peroxidase antibody (TPOAb)- and thyroglobulin antibody (TGAb)-positive exposure during gestation may contribute to offspring's adverse neural development. However, limited knowledge is available on the association between joint exposure on TPOAb and TGAb and children's emotional and behavioral development. Furthermore, the sex-specific effect on the developmental process of preschoolers' emotions and behaviors is unknown. The present research intends to examine the sex-specific effect of TPOAb- and TGAb-positive exposure in gestation on the developmental process of preschoolers' emotions and behaviors. Methods: A total of 2455 mother-child pairs were included from the Ma'anshan Birth Cohort study. The serum TPOAb and TGAb of pregnant women was measured retrospectively by electrochemical immunoassay during the follow-up period. Preschoolers' emotional and behavioral development was assessed by a child behavior checklist 1.5-5. Growth mixture modeling was adopted to fit thyroid antibody (TAb) trajectories. Poisson regression models were used, stratifying by sex, to examine the association between TAb trajectories, as well as four categories of maternal TAb exposure and preschoolers' emotional and behavioral problems. Results: Boys born to mothers with TPOAb positivity in the first, second, and third trimesters of pregnancy had an increased risk of autism spectrum problems after adjusting for confounders, with relative risk (RR) [confidence interval, CI] of 2.01 [1.24-3.27], 2.15 [1.08-4.26], and 2.13 [1.20-3.79], respectively. Maternal TGAb positivity and TPOAb negativity in the first trimester were associated with a high risk of attention-deficit/hyperactivity problems in boys (RR = 1.74 [CI 1.01-2.99]). The prevalence of depressive problems in girls was 33.3% after exposure to TPOAb alone in the third trimester of pregnancy. Exposure to TPOAb alone in the third trimester of pregnancy was associated with an increased risk of depressive problems in girls (RR = 1.78 [CI 1.09-2.90]). Conclusions: Maternal TPOAb positivity in all three trimesters was associated with the risk of autism spectrum problems in boys. Isolated maternal TGAb positivity in the first trimester was associated with attention-deficit/hyperactivity problems in boys, whereas isolated maternal TPOAb positivity in the third trimester was associated with depressive problems in girls.

Correlations of thyroid autoantibodies with allergic diseases: A case-control study of 434 Chinese patients.

There is growing interest in the relationship between allergies and autoimmune diseases, although previous studies have yielded inconsistent results.The thyroglobulin (Tg)/thyroid peroxidase antibody (TPOAb) group consisted of 217 patients with positive thyroglobulin antibody (TgAb) and/or TPOAb test results. Another set of 217 age- and sex-matched individuals with both TgAb- and TPOAb-negative results were selected as control group. History of allergic rhinitis (AR), chronic spontaneous urticaria (CSU), and/or atopic dermatitis (AD) was elicited before autoantibody detection. The association of thyroid autoantibodies with allergic diseases was assessed using univariate and multivariate logistic regression analysis, and the results were reported as odds ratios (ORs).TgAb positivity (OR, 2.333) was identified as a risk factor for AR, AD, or CSU in Chinese patients, suggesting the involvement of thyroid autoantibodies in the pathogenesis of atopic reactions. Multivariate regression analysis also confirmed that the presence of TgAb (P = .004), rather than TPOAb (P = .468), had a significant impact on the occurrence of allergic disease.Physicians should carefully monitor atopic symptoms in individuals with elevated TgAb or TPOAb levels to reduce the risk of allergic diseases, such as AR, AD, and CSU.

Anti-thyroglobulin Antibodies as a Possible Risk Factor for Graves' Disease After Radioiodine Treatment for Toxic Nodular Goiter: Case Report

BackgroundThe manifestation of Graves' disease (GD) in patients treated with radioactive iodine (RAI) for hyperfunctioning thyroid nodules (RAI-induced GD or post-RAI GD) remains a long-standing challenge in radionuclide therapy. Known risk factors for post-RAI GD include preexisting subclinical hyperthyroidism, positive thyroid peroxidase autoantibodies (TPOAb), positive TSH receptor autoantibodies (TRAb) or otherwise undiagnosed GD. However, these risk factors are not present in all patients with post-RAI GD, and therefore it cannot always be predicted in a reliable manner if a given patient has a high risk for RAI-induced GD or not.Case PresentationWe describe the case of a 64 year-old woman known for hyperthyroidism due to toxic nodular goiter; she was treated initially with carbimazole, and then, due to recurrence, underwent RAI treatment. Three months later, symptomatic hyperthyroidism persisted. Diagnosis of new-onset GD was made based on typical ultrasound findings and newly-positive TRAb. Our patient had only positive thyroglobulin antibodies (TgAb) before RAI treatment, whereas TPOAb were negative.ConclusionsIn the literature, TgAb have never been reported as a possible risk factor for RAI-induced GD. The present case suggests that the assessment for pre-existing autoimmunity in patients considering RAI for hyperfunctioning thyroid nodules should probably also include TgAb.

Epidemiological survey of the status of iodine nutrition and thyroid diseases in Guangxi, China

ObjectiveTo survey the status of iodine nutrition and the prevalence of thyroid diseases in Guangxi, China, and to explore the risk factors for positive thyroid antibody. MethodsWe used the multistage stratified cluster random sampling method to select a total of 2488 subjects from an urban and a rural location. All the subjects completed a questionnaire survey, blood and urine samples were also collected, and B-mode thyroid ultrasound was used to determine thyroid function and detect thyroid antibodies. Results1) The median level of urinary iodine was 148.53 μg/L in school-age children in Guangxi, China. 2) The prevalence rates for thyroid diseases were as follows: hyperthyroidism, 0.89 %; subclinical hyperthyroidism, 1.05 %; hypothyroidism, 0.69 %; and subclinical hypothyroidism, 8.87 %. The rates of thyroid antibody positivity were as follows: thyroid peroxidase antibody (TPOAb), 13.60 %; thyroglobulin antibody (TGAb), 13.60 %; thyroid antibodies, 18.2 %; and thyroid nodules, 16.94 %. 3) The rate of TPOAb positivity was significantly higher in women aged 18−29, 30−39, 40−49, or 60−69 years than in men in the same age groups (P < 0.05), and the TGAb positivity rate was significantly higher in women than in men of the same age group (P < 0.05). 4) The rate of thyroid antibody positivity was significantly higher in individuals with iodine deficiency than in individuals with adequate iodine (21.6 % vs 18.4 %) or excess iodine (21.6 % vs 15.5 %) (both P < 0.05). 5) The female sex and a family history of thyroid diseases were the major risk factors for thyroid antibody positivity (odds ratio [OR] 3.010, P <0.05; OR 2.486, P <0.05). ConclusionThe overall level of iodine is adequate in Guangxi, China; this level should be maintained to prevent the thyroid diseases related with iodine deficiency or excess of iodine. Female sex and a family history of thyroid diseases are independent risk factors for thyroid antibody positivity.

An evaluation of urine and serum iodine status in the population of Tibet, China: No longer an iodine-deficient region.

Iodine is a critical trace element for the synthesis of thyroid-related hormones, and either low or high iodine status can lead to thyroid dysfunction. This study aimed to evaluate the iodine status of the Tibetan population. From September 2016 to August 2018, we enrolled 1499 healthy adults from three areas of varying altitudes in Tibet. Urine iodine concentrations (UICs), adjusted UICs, and serum iodine concentrations (SICs) were measured using inductively coupled plasma mass spectrometry. The median UIC, adjusted UIC, and SIC was 137.9 μg/L, 118.4 µg/gCr, and 58.3 μg/L, respectively. Of the participants, 30.4% had UICs <100 µg/L, 63.0% had UICs ranging from 100 to 300 µg/L, and 9.6% had UICs >300 µg/L. The correlation between UIC, adjusted UIC, and SIC was good (r > 0.65, P < 0.01). The SICs were more stable than the UICs, and were not associated with age or sex. The prevalence of clinical hyperthyroidism, clinical hypothyroidism, subclinical hyperthyroidism, subclinical hypothyroidism, positive thyroid peroxide antibody, positive thyroglobulin antibody, either positive and both positive was 0.5%, 1.3%, 1.7% and 17.9%, 9.3%, 6.5%, 12.5%, and 2.5%, respectively. The prevalence of almost all thyroid disorders was higher in women than in men. This multicenter cross-sectional study found that the human iodine status of adults in Tibet was considered adequate, based on the World Health Organization's criteria.

Thyroid peroxidase antibodies are common in children with HLA-conferred susceptibility to type 1 diabetes, but are weakly associated with thyroid function.

Background The need for screening for autoimmune thyroid disease in children who have HLA-conferred susceptibility to type 1 diabetes (T1D), but have not yet been diagnosed with T1D, has not been thoroughly studied. The aim of this study was to describe the prevalence of positive thyroid peroxidase antibodies and its effect on thyroid function in children with genetic susceptibility to T1D as well as to describe the association between thyroid autoimmunity and HLA-DQ genotypes. Methods Cross-sectional study in 223 children (112 boys) aged 7.4-10.5 years with HLA-conferred susceptibility to T1D. TPOAb were measured in all children; thyroglobulin antibodies (TGAb) and thyroid function in TPOAb positive subjects. Results Girls had a significantly higher median TPOAb concentration than boys (12 vs 11 kU/L; p=0.001). Positive TPOAb occurred in 13.9% and positive TGAb in 4% of subjects. Only two children had mild changes in thyroid function. There was no association between HLA risk groups and the prevalence of TPOAb. Conclusions TPOAb are common in children with HLA-conferred susceptibility to T1D, yet are weakly associated with thyroid function, suggesting limited value of thyroid screening in this cohort.

Correction: The Relationship Between the Impairment of Endothelial Function and Thyroid Antibodies in Hashimoto's Thyroiditis Patients with Euthyroidism.

Endothelial dysfunction is the important early step in the development of atherosclerosis. Hypothyroidism caused by Hashimoto’s thyroiditis and other thyroid disease is one of the risk factors of endothelial dysfunction. The present study tried to investigate the endothelial function and its associated factors in Hashimoto thyroiditis with euthyroidism. A total of 95 newly diagnosed Hashimoto’s thyroiditis patients with euthyroidism and 45 healthy controls were studied. Hashimoto’s patients were divided into 3 subgroups namely, single thyroglobulin antibody (TGAb) positive subgroup, single thyroid peroxidase antibody (TPOAb) positive subgroup, and both TGAb and TPOAb positive subgroup. Endothelial function was tested by the reactive hyperemia index (RHI). Hashimoto’s thyroiditis patients had lower RHI than healthy controls (1.73±0.42 vs 1.96±0.51, p<0.05). Hashimoto’s thyroiditis with single TGAb positive patients had higher RHI than single TPOAb positive (1.98±0.57 vs. 1.69±0.33, p<0.05) and TGAB + TPOAb positive patients (1.98±0.57 vs. 1.68±0.42, p<0.05). RHI were negatively associated with total cholesterol (TC, r=−0.215, p<0.05), low density lipoprotein cholesterol (LDL-C, r=−0.268, p<0.05), triglyceride (TG, r=−0.192, p<0.05), and TPOAb (r=−0.288, p<0.05). In the regression analysis, LDL-C (β=−0.146, p<0.05), TG (β=−0.034, p<0.05) and TPOAb (β=−0.001, p<0.05) were independently associated with RHI. Hashimoto’s patients had poor endothelial function. TPOAb levels were negatively associated with endothelial function.

The Relationship Between the Impairment of Endothelial Function and Thyroid Antibodies in Hashimoto's Thyroiditis Patients with Euthyroidism.

Endothelial dysfunction is the important early step in the development of atherosclerosis. Hypothyroidism caused by Hashimoto's thyroiditis and other thyroid disease is one of the risk factors of endothelial dysfunction. The present study tried to investigate the endothelial function and its associated factors in Hashimoto thyroiditis with euthyroidism. A total of 95 newly diagnosed Hashimoto's thyroiditis patients with euthyroidism and 45 healthy controls were studied. Hashimoto's patients were divided into 3 subgroups namely, single thyroglobulin antibody (TGAb) positive subgroup, single thyroid peroxidase antibody (TPOAb) positive subgroup, and both TGAb and TPOAb positive subgroup. Endothelial function was tested by the reactive hyperemia index (RHI). Hashimoto's thyroiditis patients had lower RHI than healthy controls (1.73±0.42 vs 1.96±0.51, p<0.05). Hashimoto's thyroiditis with single TGAb positive patients had higher RHI than single TPOAb positive (1.98±0.57 vs. 1.69±0.33, p<0.05) and TGAB + TPOAb positive patients (1.98±0.57 vs. 1.68±0.42, p<0.05). RHI were negatively associated with total cholesterol (TC, r=-0.215, p<0.05), low density lipoprotein cholesterol (LDL-C, r=-0.268, p<0.05), triglyceride (TG, r=-0.192, p<0.05), and TPOAb (r=-0.288, p<0.05). In the regression analysis, LDL-C (β=-0.146, p<0.05), TG (β=-0.034, p<0.05) and TPOAb (β=-0.001, p<0.05) were independently associated with RHI. Hashimoto's patients had poor endothelial function. TPOAb levels were negatively associated with endothelial function.

MON-448 Detection of Thyroid Cancer Recurrence in Patients with Positive Thyroglobulin Antibody Receiving Immunoglobulin Therapy

Introduction: Differentiated thyroid cancers such as papillary and follicular thyroid cancer make up more than 90% of all thyroid cancers. The presence of thyroglobulin autoantibodies makes interpretation of the thyroglobulin level unreliable, as it could be falsely low or falsely high. Studies have shown that rising thyroglobulin antibody levels, could be used to monitor for disease recurrence in patients with negative thyroglobulin and imaging studies. However, there are challenges in detecting recurrence in patients with normal thyroglobulin level and thyroid imaging studies, who are on lifelong immunoglobulin therapy and who have increasing thyroglobulin antibody levels.Clinical case: A 63 yr old female was found to have an incidental left thyroid nodule at age 48yrs from a carotid ultrasound. She underwent US guided FNA of the thyroid nodule and was found to have papillary thyroid cancer. She had total thyroidectomy a month later, with removal of a 1.4cm primary, with no evidence of extrathyroidal extension, clear margins and no evidence of lymphovascular invasion – Stage T1bN0M0. There was left level 6 neck dissection with no carcinoma identified in the 2 lymph nodes removed. She received 105.3 mCi radioactive iodine (RAI) and whole body thyroid scan done 7 days later revealed, increased uptake involving the thyroid bed likely residual thyroid tissue. Activity was noted inferolateral to the right thyroid bed which most likely represents a lymph node. There was no evidence of distant metastasis.She was commenced on levothyroxine post operatively. Her other past medical history is significant for idiopathic urticaria and angioedema, immune deficiency disorder with low IgG and IgM and asthma. She was commenced on monthly IV immunoglobulins 5yrs post RAI therapy, due to recurrent sinusitis, rhinitis and chronic diarrhea. She was later transitioned to weekly SQ immune globulin – Hizentra which she is on till date.Over the past 15 years, serial neck ultrasounds post radioiodine ablation have been negative for recurrence. Her TSH ranged 14.91 to 0.04 (ref 0.27-4.2 uiu/ml) and thyroglobulin (Tg) titer remains <0.1 (ref <0.1). Her thyroglobulin antibody titers have trended up from <0.2 (ref <2.0) 5yrs post RAI therapy to 49 (ref <4 iu/ml)) on her most recent test this year. She is currently undergoing further work up to rule out recurrence of her cancer. In our review of the literature we found one report that showed use of Liquid Chromatography–Mass Spectrometry (LC-MS) was able to differentiate thyroid cancer recurrence in an individual with positive antithyroglobulin antibody receiving immunoglobulin therapy.Conclusion: In patients with negative Tg levels, but elevated thyroglobulin antibody while receiving immune globulin therapy, thyroglobulin antibody levels may not be a reliable indicator of thyroid cancer recurrence. Measurement of Tg levels using a LC-MS may provide some clarity.

The Impact of Obesity on Thyroid Autoimmunity and Dysfunction: A Systematic Review and Meta-Analysis

Background: To help inform decision making in the clinical setting, we carried out a systematic review and meta-analysis to estimate the association of thyroid disease risks with obesity.Methods: Pubmed, Embase, Web of Science, Cochrane database and Google Scholar electronic databases were searched from inception to October 31, 2018 without language restrictions to explore the relationship between thyroid disorders and obesity. The relative risk (RR) or odds risk (OR) for thyroid disorders were pooled using the SPSS and STATA software.Results: A total of 22 studies were included in the study. (1) Meta-analysis showed that obesity was significantly associated with an increased risk of hypothyroidism (RR = 1.86, 95% CI 1.63–2.11, P < 0.001). Meta-analyses after stratification further showed that obese population had increased risks of overt hypothyroidism (RR = 3.21, 95% CI 2.12–4.86, P < 0.001) and subclinical hypothyroidism (RR = 1.70, 95% CI 1.42–2.03, P < 0.001). (2) Further meta-analysis also showed obesity was clearly associated with Hashimoto's thyroiditis (RR = 1.91, 95% CI 1.10–3.32, P = 0.022), but not with Graves' disease. (3) In the meta-analysis of antibodies, obesity was correlated with positive thyroid peroxidase antibody (TPOAb) (RR = 1.93, 95% CI 1.31–2.85, P = 0.001), but not with positive thyroglobulin antibody (TGAb).Conclusions: Obesity was significantly related to hypothyroidism, HT, and TPOAb, implying that prevention of obesity is crucial for thyroid disorders.Systematic Review Registration: PROSPERO: CRD42018096897.

SAT-085 Severe Dyslipidemia Secondary to Autoimmune Hypothyroidism: A Case Report

Background: Up to 28% of patients have an underlying potential secondary cause for dyslipidemia. Frequently, the treatment of the underlying cause can lead to normalization of lipid profile. Case report: A 34-year-old male presented with a 12-months history of asthenia, facial swelling, cold intolerance, sleepiness, poor concentration, but stable weight. Physical examination highlighted bilateral palpebral edema. His past medical history was significant for mixed dyslipidemia at least for 2 years (total cholesterol [TC] 326 mg/dL, high-density lipoprotein cholesterol [HDL-C] 84 mg/dL, low-density lipoprotein cholesterol [LDL-C] 199 mg/dL and triglycerides [TG] 211 mg/dL), but no secondary causes of dyslipidemia were excluded, namely hypothyroidism, neither treatment was instituted. He also had overweight (body mass index [BMI] of 29 kg/m2) and hepatic steatosis. There was no familial history of dyslipidemia. Laboratory assessment revealed TC 426 mg/dL, HDL-C 89 mg/dL, LDL-C 293.6 mg/dL, TG 217 mg/dL, thyroid-stimulating hormone (TSH) > 100 μUI/mL (reference: 0.550-4.780), free thyroxine (FT4) < 0.3 ng/dL (reference: 0.70-1.58), free triiodothyronine (FT3) < 0.195 pg/mL (reference: 1.71-3.71), positive thyroglobulin antibody and negative peroxidase antibody. Thyroid ultrasonography showed a normal size gland, with heterogeneous texture and pseudonodular areas, without nodular lesions, suggesting thyroiditis. Given the diagnosis of primary autoimmune overt hypothyroidism and mixed dyslipidemia, the patient was given oral levothyroxine up to 137 μg/day and atorvastatin 10 mg/day. After normalization of thyroid function by treatment with levothyroxine, there was an important improvement in overall well-being and in the lipid profile (TC 184 mg/dL, HDL-C 46 mg/dL, LDL-C 115 mg/dL, TG 113 mg/dL), leading to statin withdrawal. Conclusion: This case highlighted a severe dyslipidemia secondary to overt autoimmune hypothyroidism in a young male. The delayed diagnosis of hypothyroidism could have been avoided if a secondary cause for dyslipidemia was initially suspected. Secondary causes of dyslipidemia, namely hypothyroidism, should be considered and excluded in any young patient with no or few risk factors.

Different Thyroidal Responses to Human Chorionic Gonadotropin Under Different Thyroid Peroxidase Antibody and/or Thyroglobulin Antibody Positivity Conditions During the First Half of Pregnancy.

Thyroid peroxidase antibody (TPOAb) positivity can attenuate gestational thyroid responses to human chorionic gonadotropin (hCG) during pregnancy, whereas the effects of thyroglobulin antibodies (TgAb) remain unknown. The aim of our study was to explore the thyroid response to hCG in women with thyrotropin (TSH) levels within the method-specific reference range under different conditions of thyroid autoimmunity. The study screened 822 women at 7-20 weeks of gestation using the pregnancy-specific reference range for TSH. Serum TSH, free thyroxine (fT4), TPOAb, TgAb, and β-hCG levels were measured using electrochemiluminescence immunoassays. The enrolled pregnant women were subdivided into four subgroups based on TPOAb/TgAb positivity: co-positive for TPOAb and TgAb (group 1), isolated TPOAb positive (group 2), isolated TgAb positive (group 3), and co-negative for TPOAb and TgAb (group 4). TSH was negatively associated with hCG in all four groups (p < 0.05). fT4 was positively associated with hCG in groups 3 and 4 (p < 0.01) but not in groups 1 (p = 0.096) and 2 (p = 0.758). Group 2 was further stratified into tertiles according to TPOAb concentrations. No negative TSH/hCG association was observed in the middle- and upper-tertile groups when TPOAb were ≥53 IU/mL (p > 0.05). There was no positive fT4/hCG association in any of the three subgroups (p > 0.05). Similarly, group 3 was further stratified into tertiles according to TgAb levels. TSH was negatively associated with hCG in the lower and middle tertiles (p < 0.01), but the association was not found in the upper tertile when TgAb was ≥356 IU/mL (p = 0.191). fT4 was positively associated with hCG in the lower tertile (p = 0.027) but not in subgroups when TgAb was ≥219 IU/mL (p > 0.05). When TSH was within the pregnancy-specific reference range, high concentrations of TPOAb and TgAb attenuated the fT4 stimulation and suppression of TSH by hCG. The results imply that TgAb, in addition to TPOAb, could also interfere with thyroidal responses to hCG during the first half of pregnancy.

The impact of thyroid function on the occurrence of metabolic syndrome in obese children and adolescents.

Thyroid axis abnormalities are common in obese patients. Their contribution in the development of metabolic obesity complications remains unclear. To assess the influence of thyroid axis dysfunction on the occurrence of metabolic obesity complications. A cross-sectional review of the thyroid function in 100 obese patients (59 girls and 41 boys, mean age 13.5 years) with alimentary obe-sity (mean standardised body mass index [BMI SDS] in boys 4.175 and girls 4.723) complicated by metabolic syndrome (MS) diag-nosed on the basis of the IDF 2006 criteria (MS, 25 patients) and uncomplicated (75 patients). TSH, fT4, fT3 thyroid peroxidase anti-bodies (TPOAb), and thyroglobulin antibodies (TGAb) were assessed in a single fasting blood sample. There was no case of overt thyroid disease within the whole analysed group. There were no significant differences in mean TSH, fT4, and fT3 levels in patients with and without MS (2.7 µIU/ml vs. 3.0 µIU/ml, 14.5 vs. 14.0 pmol/l, and 5.6 vs. 6.2, respectively; p > 0.05). In the MS group only two patients (8%) presented with a TSH level above the upper limit of the normal range; in the group without MS elevated TSH was noticed in 18 (24%) patients. The maximal value of TSH (10.44 µIU/ml) was noticed in one boy without MS. Positive TPOAb and/or TGAb were present in 11% of all patients: two patients (8%) with MS and nine (12%) without MS. Isolated increased TSH level is common in obese adolescents, although there is no correlation between TSH, fT3, and fT4 levels and BMI SDS value. Isolated increased TSH level is not associated with the occurrence of MS in obese adolescents. The occurrence of asymptomatic autoimmune thyroiditis (AITD) in obese adolescents is more common than in the general population.

Prevalencia de autoinmunidad tiroidea en una población de gestantes de Santa Marta, Magdalena (Colombia)

Objetivo: describir la prevalencia de autoinmunidad tiroidea en una población de gestantes de base hospitalaria, y hacer una exploración a la frecuencia en pacientes eutiroideas o hipotiroideas, y de la asociación entre autoinmunidad y la presencia de complicaciones obstétricas.Materiales y métodos: estudio de corte transversal, descriptivo. Población accesible: gestantes atendidas en Centros Hospitalarios del Caribe (CEHOCA), de la ciudad de Santa Marta, Magdalena (Colombia), entre el 1 de agosto y el 31 de octubre de 2017. Muestreo por conveniencia. Tamaño muestral: 120 sujetos. Se determinó hormona tiroestimulante (TSH), T4 libre, T3 libre, anticuerpos antitiroglobulina (ATG) y antiperoxidasa (ATPO). Se utilizó estadística descriptiva. La prevalencia se calculó como número de mujeres con anticuerpos ATG o ATPO positivos/número de mujeres encuestadas, además se categorizó por tipo de anticuerpo positivo y función tiroidea (normal o hipotiroidismo).Resultados: en las gestantes con embarazo sin mención de complicación la frecuencia de autoinmunidad tiroidea fue del 14,29 %. Cinco pacientes (4,5 %) presentaron anticuerpos ATPO positivos, 14 pacientes (12,61 %) anticuerpos ATG positivos, en tanto que 3 embarazadas mostraron positividad para ambos tipos de anticuerpos. Los anticuerpos antitiroglobulina fueron los más frecuentes. Se halló autoinmunidad en el 13,5 % de las gestantes eutiroideas, y en el 18,2 % de las pacientes con hipotiroidismo subclínico. No se encontró asociación entre la presencia de anticuerpos y la presencia de aborto, hipertensión asociada al embarazo o parto pretérmino.Conclusiones: una de cada 7 gestantes mostró presencia de anticuerpos antitiroideos como signo de autoinmunidad. Son necesarias más observaciones a fin de poder establecer frecuencias y rangos de normalidad en la población local y el significado clínico de esta autoinmunidad tiroidea.

A cancer of undetermined significance: Incidental thyroid carcinoma.

The incidence of thyroid cancer is increasing which can be attributed in part to improved ultrasonography (US) methods and increased detection of incidental thyroid carcinomas (ITC). We aimed to compare ITC with nonincidental thyroid carcinomas (NITC) in this study. Retrospective analyses of 906 individual patients who were operated for benign and malignant thyroid disease and had a final histopathological diagnosis of thyroid carcinoma were enrolled in this study. Preoperative US examination and fine needle aspiration (FNA) biopsy results were evaluated. The tumor foci in thyroidectomy specimens that were not represented in preoperative US or FNA reports were classified as ITC. The tumor foci that match with the lesions defined in US or FNA results were classified as NITC. Final histology revealed ITC in 326 patients (36%) and NITC in 580 patients (64% Mean age was 51.7 ± 11.11 in ITC group and 48.15 ± 13.1 in NITC group (P < .001). In NITC group 322 (55.5%) of the patients were operated for suspicious cytology while only 29 (8.9%) of the patients in the ITC group were operated because of this indication (P < .001). There were 1301 cancer foci in histopathology specimens. Among all these cancer foci, 434 (33.3%) were detected incidentally and 867 (66.7%) were detected non-incidentally. About 779 (89.9%) of nonincidental cancer foci were papillary cancer (PTC), while all of the incidental cancer foci were PTC. Mean size was 13 mm in NITC group and it was 3 mm in the ITC group and differed significantly between the groups (P < .001). Tumor size was ≤1 cm in 35.2% of the patients with NITC while 98.5% of patients with ITC had tumor ≤1 cm. The occurrence of multinodularity was higher in ITC than the NITC group (P < 001). Median TSH level was higher in patients with NITC than ITC while both were in the reference range (1.53 vs 1.03 μIU/mL, P < .001). The frequency of thyroiditis detected by US, and thyroid peroxidase antibody and thyroglobulin antibody positivities were similar in patients with ITC and NITC (P = .2, P = .86, and P = .26, respectively). The frequencies of capsular invasion (29.1% vs 7.9%), extrathyroidal extension (13% vs 4.2%), multifocality (35.8% vs 24.2%), non-complete resection (9.2% vs 1.8%), and lymph node metastasis (9.5% vs 1.8%) were significantly higher in the NITC group (P < .001, for each). Persistent/recurrent disease in patients with NITC was more frequent than patients with ITC (P = .004). This outcome was similar for cancers measuring ≤1 cm (P = .001). ITC is often encountered in older patients and frequently determined in early stages with more favorable histopathological features and better prognosis.