Incidence Of Thyroiditis Research Articles

Autoimmune thyroiditis incidence in a large population-based study in northeastern Italy.

An improvement in iodine status in the Veneto region (Italy) in the last decade has been documented. Our aim was to estimate the incidence of autoimmune thyroiditis (AT) in this region over the period 2012-2022. A retrospective population-based study conducted in Veneto using the population registry and administrative health databases. We documented incident hyperthyroidism from 2013 to 2022 to exclude prevalent cases and calculated standardised incidence rates (IR) per 10,000 person-years by age and sex. We identified 65,379 incident cases (IR: 13.38), 5.44-fold higher in females than in males. IR decreased from 15.86 (95% CI: 15.50, 16.21) in 2013 to 12.35 (95% CI: 12.04, 12.67) in 2022. The decline was evident only in females, with a documented reduction in IR from 27.26 (95% CI: 26.61, 27.91) in 2013 to 20.49 (95% CI: 19.92, 21.07) in 2022 (P = 0.002). The decrease was sharper in females aged 15-54 years (IR from 37.86 (95%CI: 36.79, 38.94) in 2013 to 27.40 (95% CI: 26.44, 28.36) in 2022; P < 0.001) than in those aged ≥55 years (IR from 20.06 (95% CI: 19.13, 20.99) in 2013 to 16.56 (95% CI: 15.78, 17.35) in 2022; P = 0.034). In 2020, an out-of-trend decrease in AT incidence was documented, corresponding with the SARS-CoV-2 pandemic, with a realignment to the trend in the subsequent years. A decline in AT was documented in the Veneto region in the last decade, paralleling improvement in the iodine status. The reduction was significant only among females, particularly in reproductive age.

Metabolic Disease and Risk of Thyroid Disease: Evidence from the National Nurse Health Cohort in China.

Previous studies have shown that metabolic diseases are risk factors for thyroid disease; most studies are cross-sectional design. We aimed to evaluate the causal relationship between thyroid and metabolic diseases in a cohort of Chinese nurses. We conducted an ambispective cohort study of the National Nurses' Health Study. Thyroid disease data based on ultrasonography from 2017 to 2021 were collected. We described thyroid disease incidence and the risk factors associated with a cluster of metabolic factors. We used the Mann‒Whitney U test, repeated-measures ANOVA and multivariable Cox proportional hazard regression to analyze the data. A total of 1529 female nurses without thyroid disease were enrolled in 2017, of which, complete data were available for 1269 nurses. In 2018-2020, thyroid nodule incidence ranged from 32.8%-46.3%, thyroiditis incidence was 13.4%-14.3%, and goiter incidence was 4.1%-29.1%, thyroid adenoma and thyroid tumors incidence were 0.1%-0.5% and 1%-1.5%. We also found that NAFLAD was an independent risk factor for thyroid adenoma (p = .003). The age at diagnosis was an independent risk factor for goiter (p <. 001) and thyroid nodules (p < .001). Fasting blood glucose was an independent risk factor for thyroid tumors (p = .004). The age at diagnosis (p = .003), Body Mass Index (p = .006) and menopause (p = .031) were risk factors for thyroiditis. Thyroid disease incidence among nurses is increasing. Age at diagnosis, BMI, fasting blood glucose, and nonalcoholic fatty liver disease are independent risk factors for different types of thyroid disease. This study provides evidence for future studies to further explore the pathogenesis and prevention of thyroid diseases.

IL-9-Producing Th9 Cells Participate in the Occurrence and Development of Iodine-Induced Autoimmune Thyroiditis.

Iodine excess may cause and aggravate autoimmune thyroiditis (AIT), which is regarded as a typical kind of autoimmune disease mainly mediated by CD4+ T cells. Thus far, it is unclear whether T helper (Th) 9 cells, a novel subpopulation of CD4+ T cells, play a potential role in AIT. Therefore, in the present study, changes in Th9 cells were detected in murine models of AIT induced by excess iodine intake to explore the possible immune mechanism. Female C57BL/6 mice were divided into 7 groups (n = 8) and were supplied with water containing 0.005% sodium iodide for 0, 2, 4, 6, 8, 10, and 12weeks. With the extension of the high-iodine intake duration, the incidence of thyroiditis and the spleen index were significantly increased, and serum thyroglobulin antibody (TgAb) titers and interleukin 9 (IL-9, major cytokine from Th9 cells) concentrations were also increased. Additionally, it was revealed that the percentages of Th9 cells in spleen mononuclear cells (SMCs) and thyroid tissues were both markedly elevated and accompanied by increased mRNA and protein expression of IL-9 and key transcription factors of Th9 cells (PU.1 and IRF-4). Significantly, dynamic changes in Th9 cells were found, with a peak at 8weeks after high iodine intake, the time point when thyroiditis was the most serious. Importantly, Th9 cells were detected in the areas of infiltrating lymphocytes in thyroid sections. In conclusion, the continuously increasing proportions of Th9 cells may play an important role in the occurrence and development of AIT induced by high iodine intake.

Clinical, laboratory and ultrasound characteristics of autoimmune thyroiditis in the children’s population of territories with the location of metallurgical enterprises

Introduction. The combination of iodine deficiency and the negative impact of environmental factors determines the pathomorphism of thyroid diseases, including autoimmune thyroiditis (AIT). The purpose of the study was to establish clinical, laboratory, and ultrasound features of autoimmune thyroiditis in children living under the influence of metallurgical production. Materials and methods. AIT children residing in the zone of influence of the enterprises of the metallurgical industry (one hundred two cases) and outside the exposure zone (46 people) underwent a comparative analysis of the results of clinical and laboratory research, ultrasound imaging of thyroid gland tissues. Results. During the period 2010-2020, the increase in the incidence of thyroiditis in the territory with metallurgical production enterprises exceeded the average indicator in the Perm region by 1.5 times. Children from the test group had concentrations of lead, manganese, nickel, chromium and zinc in their blood higher than the regional background level. These elevated concentrations were detected in them by 1.7-5.5 times more frequent than in their counterparts from the reference group. The number of AIT cases elevated by 2 times in the exposed boys; diffuse lesions of the thyroid gland and combination of AIT with other diseases, by 1.3 times (p = 0.03-0.04). Levels of IgA and IgG in blood serum were by 2.7 times higher in the test group (p = 0.015-0.043); TSH contents, by 2.3 times higher (p = 0.096); free T4 contents, by 5.4 times lower (p = 0.057). Limitations of the study. Children living at the only one subject of the Russian Federation; a comparatively small sampling; selected study of compounds with direct thyreo-cytotoxic effects Conclusions. Incidence of thyroid gland diseases and thyroiditis in territories with developed metallurgic industry is higher than on territories with a relative favorable sanitary-hygienic situation. Children with elevated contents of metals in their blood had disorders of thyroid and immune status, thyroid gland disease and concomitant damage to other systems in the body. The mathematical relationships indicate the possible influence of metals on the formation of AIT.

Posibila asociere dintre diabetul zaharat de tip 2 şi tiroidita autoimună Hashimoto – rezultate finale

Introduction. The idea for our clinical research came from the association between type 2 diabetes and autoimmune thyroiditis that we often see in our daily practice. We wanted to study this to see if it is only a coincidence or if indeed this association really exists. Method. We created an observational retrospective research using 5,064 patients with type 2 diabetes, patients from Sanamed Hospital, which came at site between January 2016 and December 2018. Out of the large group of patients, we created 3 secondary groups: one containing 50 patients with type 2 diabetes, one with 50 patients with autoimmune thyroiditis and one with 50 patients which had both diseases. We initially evalueted the large group and after that we studied the 3 smaller groups. Results. We were able to prove the main hypothesis of our study by showing that the incidence of thyroiditis was significantly higher in the population with type 2 diabetes from our main group, the 5,064 patients, in contrast with the incidence that thyroiditis has in the healthy population from Europe. In our study we also demonstrated that the association between this 2 diseases has a protective role in regards with the incidence of obesity, arterial hypertension, dyslipidemia and macrovascular complications of the type 2 diabetes. Also, we found out that in the case of this association there are significant differences for a serial of biochemical parameters as well, such as blood glucose, uric acid, elements of the lipid profile. Discussions. The results from our study were consistent with the results form other international studies regarding this topic. This finding led us to the conclusion that our initial observation, that this two conditions might be associated, was not only a coincidence, but it is a definite association proved by us in this study. Conclusions. We proved our initial hypothesis to be true by the significant difference in incidence of thyroiditis in the population of our study in comparison with the incidence of thyroiditis in the healthy European population. We also managed to prove the secondary hypothesis to be correct.

An Estimation of the Incidence of Thyroiditis Among Girls in Primary Care in Spain

Objective:As for other auto-immune processes, thyroiditis is monitored after vaccinations. The aim was to estimate the baseline incidence of thyroiditis among girls, before investigating papillomavirus vaccination as a potential risk factor.Methods:Observational cohort study including girls aged 9-18 years and registered between 2002-2016 in the Spanish Primary Care Database for Pharmacoepidemiological Research. Girls were followed until a thyroiditis occurred, 19 years of age, left the cohort, died, or the study ended. Anonymized records were reviewed for diagnosis confirmation (endocrine discharge letter and/or free-text comments) in a random sample. Incidence rate (IR) per 105 person years (/105 py) was estimated.Results:The cohort numbered 480,169 girls, of whom 641 had a record of thyroiditis: 346 autoimmune thyroiditis; 17 thyroiditis of other types; and 278 unspecified. Incidence of recorded thyroiditis increased with age, from 23.96 at age 9 years to 47.91 at age 14 years, and stabilized around 31.06-34.43 among girls aged 15-18 years. Of the 98 records reviewed, 60.2% were ‘confirmed’ cases, 32.7% ‘possible’ and 7.1% were discarded. After correction for discarded cases, IR=20.83 ‘confirmed’ cases, increasing to 32.12/105 py when ‘confirmed’ plus ‘possible’ cases were included. Between 2002-2005, incidences were lower (16.28 and 20.93 cases/105 py) than in the period 2007-2016 (21.17 and 33.78 cases/105 py) for ‘confirmed’ and ‘confirmed’ plus ‘possible’, respectively.Conclusion:Two-thirds of the recorded thyroiditis included confirmatory evidence. The incidence of thyroiditis among girls increased with age and in the later period, and remained stable among girls aged 15-18 years.

Metabolic, Hormonal, Immunologic, and Genetic Factors Associated With the Incidence of Thyroid Disorders in Polycystic Ovarian Syndrome Patients.

Many endocrinopathies have been increasingly affecting females of reproductive age. Polycystic ovary syndrome (PCOS) and hypothyroidism are some of the most common endocrinopathies seen in females. The aim of this study is to find a relationship between the incidence of thyroiditis in polycystic ovarian syndrome patients. Literature review search was conducted via a series of systematic searches using multiple databases which lead to cross-referencing of articles within assigned criteria. Our study resulted in a review of 42 articles pertaining to our study. In this literature review article, factors were identified associating PCOS with thyroiditis. A viable relationship was found between the incidence of PCOS and thyroiditis. The combination of factors seen in this study proposes that clinicians may need to focus on certain markers regarding the screening of the incidence of thyroiditis. We also recommend future cohort studies to be conducted to further confirm the associations identified in this article.

Risk of Thyroid Dysfunctions with Use of Immune Checkpoint Inhibitors: A Meta-Analysis of Randomized Controlled Trials

Background: Immune checkpoints, by interacting with their ligands, modify the actions of immune cells. By inhibiting or manipulating this interaction by using checkpoint inhibitors (CPIs), we can harness the powers of the immune system to treat malignancies. CPI targets include PD1, PD-L1, or CTLA-4. CPIs have traditionally been used to treat solid malignancies like melanoma and lung cancer, but recently many trials established efficacy for hematological malignancies. CPIs can cause various immune-related adverse events, and the most significant ones are related to the endocrine system. In this meta-analysis, we will assess the risk of thyroid dysfunctions with CPIs in the light of data from randomized controlled trials (RCTs). Methods: We performed a comprehensive literature search on PubMed, Embase, clinicaltrials.gov, and Cochrane databases from inception till July 12, 2020. We used keywords for different checkpoint inhibitors. We used the filter for randomized controlled trials. We screened 9859 articles and selected 48 randomized clinical trials (N=27, 275), that reported the incidence of hyperthyroidism, hypothyroidism, or thyroiditis in CPIs vs. placebo/chemotherapy. Case reports, case series, observational studies, review articles, meta-analysis, single-arm trials, RCTs not reporting data on thyrotoxicity, and RCTs with thyrotoxic drugs in the control group were excluded. Screening and data extraction were done according to PRISMA guidelines. Meta-analysis was performed using the R programming language (version 4.0.2). Results: Our literature search yielded 9859 articles. After excluding the articles based on the predefined criteria described above, we included 48 articles and found the incidence of hypothyroidism, hyperthyroidism, and thyroiditis reported in 48, 31, and 18 RCTs, respectively. In 48 RCTs (n=27,275), 14 RCTs (n=7151) had patients with median age ≤ 60 years, while 34 RCTs (n=20,125) had patients with median age &amp;gt; 60 years. 27 RCTs (n= 13,582) used PD-1 targeting CPIs, 8 RCTs (n=5,589) studied CTLA-4 targeting CPIs, 9 RCTs (n= 6,020) involved PD-L1 targeting CPIs and 4 RCTs (n= 2084) used a combination of two CPIs. In RCTs reporting treatment related hypothyroidism, the total number of patients were 27,275 (CPI arm = 14,771, Control arm = 12, 504). For all grade treatment related hypothyroidism, the risk ratio (RR) was 7.04 [5.47; 9.05, p &amp;lt; 0.0001, I2 = 20%] in favor of control group. Upon subgroup analysis, the maximum RR of 12.25 [5.38; 27.89, I2 = 0%] was seen in RCTs using two CPIs vs. placebo/chemotherapy. For ≥ grade 3 treatment related hypothyroidism, risk ratio was 1.56 [0.94; 2.58, p= 0.09, I2 = 0%] in favor of control group. In the 31 RCTs (n= 17,257; CPIs = 9495; Control= 7762) reporting hyperthyroidism, the risk ratio for all grade hyperthyroidism was 6.39 [4.71; 8.68, p &amp;lt;0.001, I2= 0%] in favor of control group. Similar to hypothyroidism, maximum risk of hyperthyroidism was also seen in RCTs using combination regimens of CPIs vs. placebo/chemotherapy, RR=14.76 [3.51; 61.98, I2= 0%]. The RR for ≥ grade 3 treatment related hyperthyroidism was 1.38 [0.76; 2.53, I2= 0%]. In the 18 RCTs (n= 10,846; CPIs = 6082; Control= 4764) reporting the incidence of thyroiditis, the RR was 3.12 [1.58; 6.15, p = 0.001, I2= 0%] in favor of control group. The highest risk ratio for thyroiditis was seen in PD-1 targeting checkpoint inhibitors (RR= 3.82 [1.73; 8.43, I2= 0%]). Conclusion: Although checkpoint inhibitors significantly increase the incidence of hypothyroidism, hyperthyroidism, and thyroiditis, most of the reported effect was grade 1 or 2 category. CPIs also increased the risk of treatment-related grade ≥ 3 thyroid dysfunctions, but the results were not statistically significant. We recommend that clinicians should be vigilant about autoimmune disorders and routinely monitor patients for thyroid disorders while using CPIs. Disclosures Anwer: Millennium Pharmaceuticals: Research Funding; AbbVie Pharmaceuticals: Research Funding; Celgene: Research Funding; Astellas Pharma: Research Funding; Acetylon Pharmaceuticals: Research Funding; Seattle Genetics: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Speakers Bureau; Incyte Pharmaceuticals: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Speakers Bureau.

Effects of Environmental Chemicals on the Course of Autoimmune Thyroiditis

Introduction. The relevance of the research is attributed to the increased incidence of autoimmune thyroiditis in children, especially those dwelling in contaminated areas. Our objective was to study effects of environmental exposures to industrial chemicals on the course of autoimmune thyroiditis. Materials and methods. In order to establish the relationship between specific features of the course of autoimmune thyroiditis and adverse environmental exposures, we conducted a comparative study of incidence rates of thyroid diseases including thyroiditis, cytotoxicity testing, thyroid status assessment, antioxidant activity assays, and thyroid ultrasound. The observation group consisted of 98 children living the area with the developed metallurgical industry while the comparison group included 23 children living in a recreation area. The groups were matched by age and socio-economic characteristics. Results. We established that thyroiditis incidence rates in the industrially polluted area were almost thrice as high as those in the relatively clean area. The observation group was characterized by smoothed sexual differentiation, earlier development of the autoimmune thyroiditis, higher (up to 1.6 times) frequency of typical diffuse structural changes, and increased thyroid gland. Blood levels of metals having a direct cytotoxic effect on the thyroid gland were 2.0 to 6.7 times higher than normal in the cases compared to their matched controls. The correlation and regression analysis established contribution of chemicals to the increased incidence of autoimmune thyroiditis in children (zinc), antibodies to thyroid gland tissue (lead), thyroid-stimulating hormone (nickel), and decreased resistive indices (lead). Conclusion. High blood levels of lead, nickel and zinc were among the factors having an adverse effect on the course of AIT and thyroid function.

Is there a correlation between thyroiditis and thyroid cancer?

In the past few decades, the incidence of thyroid cancer has increased significantly all over the world. In the same period, there also seems to have been an increase in the incidence of Hashimoto's Thyroiditis-the most common inflammatory autoimmune thyroid disease. Several studies have linked thyroiditis to thyroid cancer. In our study, we examined 2304 cases of thyroid surgery collected over a 12-year period starting from 2004. In 2090 cases (90.7%) out of our sample, it has been possible to compare the presence, or lack thereof, of thyroiditis by means of a histological diagnosis post-surgery; 214 (9.3%) cases were excluded from our study due to insufficient data. We then divided the different histological classifications into two groups. Group A included all the benign histological classifications and Group B included all the malignant histological classifications. In each group, we then assessed the presence, or lack thereof, of thyroiditis in order to evaluate if thyroiditis can be linked to a higher incidence of thyroid cancer. Data analysis showed a higher incidence of thyroiditis in Group B, 36.4% (malignant pathology report), than in Group A, 32.4% (benign pathology report), but no statistically significant difference emerged between those two groups (P > 0.05). Our conclusion was that a correlation between thyroiditis and a higher incidence of thyroid cancer is still undefined.

Association of Certain HLA-II/DR Alleles with Incidence of Thyroiditis in Iraqi Patients

Association of Certain HLA-II/DR Alleles with Incidence of Thyroiditis in Iraqi Patients

Patients with Oncocytic Variant Papillary Thyroid Carcinoma Have a Similar Prognosis to Matched Classical Papillary Thyroid Carcinoma Controls.

Previous studies have suggested that oncocytic variant papillary thyroid carcinoma (PTC) may be more aggressive, with higher rates of recurrent disease. The aim of this study was to evaluate characteristics and outcomes of patients with oncocytic variant PTC compared to classical PTC. Patients with oncocytic variant PTC were retrospectively identified from 519 patients who underwent thyroidectomy for PTC between January 2009 and August 2015. Data collected included patient demographics, laboratory and pathology findings, imaging studies, treatment, and follow-up. Patients were matched 1:1 by age, sex, and TNM stage with patients who underwent total thyroidectomy for classical PTC during the same time period. The cohort included 21 patients, of whom 18 (86%) were female, with a median age of 53 years (range 23-68 years). All patients underwent total thyroidectomy, and 17 (81%) had a central compartment neck dissection (8 [38%] prophylactic). The median tumor size was 2.0 cm (range 0.9-6.5 cm), and four (19%) patients had extrathyroidal extension. There was no significant difference in histopathologic characteristics, including extrathyroidal extension and lymphovascular invasion, between the two groups except for an increased incidence of thyroiditis in oncocytic variant PTC (90.5% vs. 57%; p = 0.01). In oncocytic variant PTC patients who underwent central compartment neck dissection, malignant lymph nodes were found in 12 (57%) patients compared to 13 (62%) classical (p = 0.75). Lateral neck dissection was performed in 5 (24%) oncocytic variant and classical PTC patients, with metastatic lymphadenopathy found in four (a median of four malignant lymph nodes; range 1-6) and five (a median of 2.5 malignant lymph nodes; range 1-9), respectively. Radioactive iodine was administered to 18 (86%) oncocytic variant PTC and 18 (86%) classical PTC patients. At a median follow-up of 51 months (interquartile range 38-61), one oncocytic variant PTC patient had recurrent disease and underwent reoperation at 24 months. In classical PTC patients with a median follow-up time of 77 months (range 56-87 months), two (9.5%) patients had detectable thyroglobulin levels indicating early recurrence, but neither has undergone reoperation. Oncocytic variant PTC was present in 5% of PTC patients. Most (95%) patients remain disease-free at four years, similar to classical PTC outcomes, suggesting that oncocytic variant may not represent a more aggressive variant.

Thyroiditis: a Clinico-cytomorphological Study with a Reference to the Ethnic Groups of Northeast Regions of India.

Definite clinico-cytological criterion is outlined for thyroid lesions. Fine needle aspiration cytology (FNAC) makes it easier to segregate cases of thyroiditis (Chronic lymphocytic thyroiditis/Hashimoto's thyroiditis-CLT/HT, and subacute thyroiditis-SAT) from other benign and malignant lesions of thyroid. The study was done for a period of 5½ years at a diagnostic centre in Guwahati. Patients underwent FNAC and smears were studied for cytomorphology. A correlation with clinical features and thyroid function, including antithyroid antibody estimation, was done, wherever possible. 792 thyroid lesions were encountered during the study, of which 213 (26.89%) were cases of thyroiditis (70.43% CLT/HT, 24.9% SAT and 3.76% having overlapping features of CLT/HT and SAT); 2 cases (0.9%) of CLT showed suspicion of Non-Hodgkin's Lymphoma (NHL), which was confirmed on histopathology. 24 cases (11.26%) belonged to different ethnic tribal groups of Northeast India. CLT/HT presented predominantly with diffuse thyroid enlargement, but 12 cases (8% of CLT/HT cases) had nodular enlargement. Patients presented with predominantly hypothyroidism; however occasional hyperthyroid cases were also seen. SAT showed signs of inflammation and presented with hyperthyroidism. Overlap cases of CLT/HT and SAT showed combined clinico-cytomorphological features of both lesions. 37.5% cases with overlapping features belonged to tribal communities. A rise in incidence of thyroiditis, particularly CLT/HT, was seen. Overlap features of CLT/HT and SAT was noticed in significant percentage. No bias was noticed amongst any specific tribal community. FNAC, coupled with clinico-serological study, helps to diagnose thyroiditis at early stage.

Thyroid Dysfunction as an Unintended Side Effect of Anticancer Drugs

Several of the currently used anticancer drugs may variably affect thyroid function, with impairment ranging from modified total but not free concentration of thyroid hormones to overt thyroid disease. Cytotoxic agents seem to alter thyroid function in a relatively small proportion of adult patients. Anticancer hormone drugs may mainly alter serum levels of thyroid hormone-binding proteins without clinically relevant thyroid dysfunction. Old immunomodulating drugs, such as interferon-α and interleukin-2, are known to induce variably high incidence of autoimmune thyroid dysfunction. Newer immune checkpoint inhibitors, such as anti-CTLA4 monoclonal antibodies, are responsible for a relatively low incidence of thyroiditis and may induce secondary hypothyroidism resulting from hypophysitis. Central hypothyroidism is a well-recognized side effect of bexarotene. Despite their inherent selectivity, tyrosine kinase inhibitors may cause high rates of thyroid dysfunction. Notably, thyroid toxicity seems to be restricted to tyrosine kinase inhibitors targeting key kinase-receptors in angiogenic pathways, but not other kinase-receptors (e.g., epidermal growth factor receptors family or c-KIT). In addition, a number of these agents may also increase the levothyroxine requirement in thyroidectomized patients. The pathophysiology of thyroid toxicity induced by many anticancer agents is not fully clarified and for others it remains speculative. Thyroid dysfunction induced by anticancer agents is generally manageable and dose reduction or discontinuation of these agents is not required. The prognostic relevance of thyroid autoimmunity, overt and subclinical hypothyroidism induced by anticancer drugs, the value of thyroid hormone replacement in individuals with abnormal thyrotropin following anticancer systemic therapy, and the correct timing of replacement therapy in cancer patients need to be defined more accurately in well-powered prospective clinical trials.

Iodine increases and predicts incidence of thyroiditis in NOD mice: Histopathological and ultrastructural study

Prolonged intake of large amounts of iodine has been reported to increase the incidence of hypothyroidism in humans, as well as in animals which are prone to spontaneously developing autoimmune thyroiditis. We sought to investigate the histopathological consequences of large amounts of dietary iodine on the thyroid gland and observe the occurrence of lymphocytic infiltration associated with the time of exposure to iodine. An experimental model using non-obese diabetic (NOD) mice was analyzed. A potassium iodide intake of 0.2 mg/animal/day was administered via drinking water, in experimental groups of 60 and 90 days (EG60 and EG90). Distended rough endoplasmic reticulum, degenerated mitochondria, debris and amorphous spaces or ‘ill-defined’ spaces were observed with electron microscopy (EM). Lymphocyte infiltration was observed in the two groups and the time of exposure to iodine did not increase the appearance of lymphocyte infiltration but significantly associated with the development of necrosis. The results of the present study demonstrated that the NOD mouse is a feasible experimental model for thyroiditis induced by iodine administration and may represent an opportunity to analyze the steps and factors associated with genetic autoimmune thyroiditis. High doses of ingested iodine were observed to precdict and increase the incidence of the thyroiditis process.

Selenium and the thyroid: A close-knit connection

Introduction:In areas with severe selenium deficiency higher incidence of thyroiditis has been reported due to a decreased activity of selenium-dependent glutathione peroxidase enzyme within thyroid cells.Aims and Objective:To study the effect of selenium supplementation in patients with autoimmune thyroid disease.Materials and Methods:This is a blinded placebo-controlled prospective study done in 60 patients with autoimmune thyroid disease (as defined by an anti-thyroid peroxidase antibody (TPOAb) level more than 150 IU/ml) irrespective of the baseline thyroid status. Patients with overt hyperthyroidism who are on antithyroid drugs, patients on any other medication, which may alter the immunity status of the patients, and pregnant patients were excluded from the study. Patients were randomized into two age and TPOAb-matched groups; 30 patients received 200 μg of sodium selenite/day, orally, for 3 months, and 30 patients received placebo. All hypothyroid patients were given l-thyroxine replacement.Results:Of 30 patients in the selenium treated group, 6 patients were overtly hypothyroid, 15 were subclinical hypothyroid, 6 were euthyroid, and 3 were subclinical hyperthyroid. The mean TPOAb concentration decreased significantly by 49.5% (P < 0.013) in the selenium treated group versus 10.1% (P < 0.95) in the placebo-treated group.Conclusion:Selenium substitution has a significant impact on inflammatory activity in thyroid-specific autoimmune disease. It would be of interest to determine whether early treatment with selenium in patients with newly developed autoimmune thyroiditis may delay or even prevent the natural course of these diseases.

Minimally invasive video-assisted thyroidectomy: an analysis of results and a revision of indications

The first report of minimally invasive video-assisted thyroidectomy (MIVAT) was published in 1999, and the indications were progressively implemented: from cytologically undetermined thyroid nodules to intermediate-risk differentiated thyroid cancers. The aim of this study was to review the entire series of patients who underwent a MIVAT, critically analyzing its indications and contraindications and trying to figure out how the indications might be extended. From 1998 to 2009, a total of 1,946 patients (1,659 females, 287 males; mean age = 40.2 years) underwent MIVAT in our department. Inclusion criteria were benign thyroid nodules <35 mm, malignant nodules <20 mm, and an ultrasonographically estimated thyroid volume (ETV) <25 cc. The presence of suspicious or metastatic lymph nodes and the presence of severe thyroiditis were considered a contraindication for MIVAT. A total thyroidectomy was performed in 1,435 patients (72.3%). A total lobectomy was performed in 511 cases (26.3%), and a central neck node sampling was associated with total thyroidectomy in 104 cases. Final histology revealed benign disease in 979 cases (51.5%) and a malignancy was diagnosed in 915 cases (48.5%). Unexpected thyroiditis was found on final histology in 17.9% of the patients with benign disease and 30.9% of patients with malignancy. The incidence of thyroiditis was significantly different in these two populations (p < 0.0001). Our data confirm the validity of the traditional indications for MIVAT: low-risk differentiated thyroid cancer (DTC), cytologically undetermined nodules, and small-volume benign thyroid disease. The indications may be further and safely extended to those patients with associated thyroiditis and those with intermediate-risk DTC. MIVAT can be proposed on a much larger scale than it was at its onset and cannot be considered an option for only a limited number of patients.

Experimental autoimmune thyroiditis in human parvovirus B19 transgenic mice

Viral infection is implicated as a cause of autoimmune diseases. Whereas its role in Hashimoto's thyroiditis (HT) remains undefined, recent studies suggested a link between human parvovirus B19 (B19) infection and HT. We tested such possibility by using B19 nonstructural protein 1 (NS1) transgenic C57BL/6 mice, which harbor nonpermissive genetic background (H-2b). Mice were immunized with either thyroglobulin (Tg) or saline. No thyroiditis developed in saline-treated mice and Tg-immunized males regardless of the presence or absence of NS1. In contrast, thyroiditis was induced by Tg immunization in 25% of transgenic females, but not in wild-type females. However, the thyroiditis incidence in the former did not differ significantly from that of the latter. In addition, intrathyroidal T-cell receptor gene expression was not augmented in Tg-immunized transgenic females. Immunization with Tg led to a comparable increase in serum anti-Tg antibody levels in the wild-type and transgenic mice. Our results indicate that the introduction of B19 NS1 gene into C57BL/6 mice is insufficient to promote the development of autoimmune thyroiditis. Further studies are required, however, before concluding that B19 infection is not involved in HT induction.

DEPENDENCE INCREASE OF AUTOIMMUNE THYROIDITIS INCIDENCE TO GENDER, AGE AND IRRADIATION DOSE IN THE POPULATION, AFFECTED BY CHERNOBYL NUCLEAR POWER PLANT ACCIDENT

Conducting radiation-epidemiological cohort study showed that children and adolescents exposed to iodine radionuclides, there was increase autoimmune thyroiditis incidence. The average increase in the incidence was 1.6 cases per 1000 person-Gy or 8,2 % per unit increase in dose (1,0 Gy). However, only in boys aged 0-3 years were obtained statistically significant estimates of radiation risk: the excess relative risk (ERR) - 0,73 to 1,0 Gy (CI = 0,017 ÷ 1,44), excess absolute risk (EAR) - 3,1 per 104 person-year Gy (CI = 0,25 ÷ 5,87) and the attributive risk - 42,2 %.

Parathyroid Hormone Deficiency After Total Thyroidectomy: Incidence and Time

Parathyroid hormone (PTH) deficiency or hypoparathyroidism after total thyroidectomy is not an uncommon postoperative complication. Patients who have PTH deficiency will develop profound hypocalcemia if not properly treated with oral calcium supplementation and activated vitamin D (1,25-dihydroxycholecalciferol or calcitriol). However, there is little published on the long-term outcomes of these patients. The aim of this study was to determine the incidence of PTH deficiency and the time course to resolution after total thyroidectomy. We identified 271 consecutive patients who underwent total thyroidectomy from January 2006 to December 2008. All patients had serum PTH levels tested 4 h after surgery and the morning after surgery. Patients were diagnosed with PTH deficiency if their serum PTH was <10 pg/mL. The outcomes of patients with PTH deficiency (group 1) were then compared with patients who did not have PTH deficiency (group 2). Patients in group 1 were evaluated for parathyroid function by measuring serum PTH levels as well as documenting usage of supplemental calcium and 1,25-dihydroxycholecalciferol. Of the 271 patients, 33 (12%) were found to have PTH deficiency. In comparing PTH deficient patients (group 1) with patients in group 2, there were no differences in age, gender, thyroid pathology, the incidence of thyroiditis, or other factors that would predict hypoparathyroidism. Twenty-four patients (73%) had recovery of their PTH levels to > or =10 pg/mL at their 1 wk follow-up appointment, while 9 (27%) patients still had PTH levels <10 pg/mL. With long term follow-up, 27 (82%) patients had recovered with a PTH level of > or = 10 pg/mL, while 6 (18%) patients had a serum PTH level <10 pg/mL. However, three of the 33 patients in group 1 (9%) required long-term 1,25-dihydroxycholecalciferol, but only two of these patients had undetectable PTH levels. Thus, the overall rate of hypocalemia requiring 1,25-dihydroxycholecalciferol was <1% (two of 271 total patients). We concluded that approximately 12% (33 of 271) of patients undergoing total thyroidectomy will develop PTH deficiency. Of the PTH deficient patients, 73% will return to normal parathyroid function within 1 wk of surgery. Furthermore, 82% of these PTH deficient patients will return to normal parathyroid function with long-term follow-up. Less than 1% (two of 271) of patients undergoing total thyroidectomy will require 1,25-dihydroxycholecalciferol for long-term hypocalcemia.