Total T4 Levels Research Articles

Hyperprolactinemia in patients with high TSH levels with both clinical and subclinical hypothyroidism

Hyperprolactinemia is the most common endocrine disorder involving hypothalamic–pituitary axis. This results from multiple causes such as medications, hypothyroidism, and pituitary disorders. Hyperprolactinemia and hypothyroidism are closely interrelated conditions. The present study aimed to estimate serum prolactin levels and determine the prevalence of hyperprolactinemia in newly diagnosed subclinical and clinical hypothyroid patients and correlation between TSH and prolactin levels in subclinical and clinical hypothyroid patients.This study was conducted in the Department of Biochemistry, in collaboration with Department of Medicine, Department of Obstetrics and Gynecology, LATE BRKM Government Medical College, Jagdalpur, Chhattisgarh, India. Total of 138 patients presenting to Department of Medicine for various thyroid related problems were involved in this study. The newly diagnosed cases of primary hypothyroidism were included in this study. The demographic, physical and clinical history was taken from all the study subjects. In the present study, serum prolactin levels were significantly increased in subclinical (28.7 ± 6.4 ng/mL) and clinical hypothyroidism (15.02 ± 4.2ng/mL) compared to controls. Hyperprolactinemia was observed in 11 (22.9%) patients in subclinical hypothyroidism and 4 (8.3%) in clinical hypothyroid patients. In the subclinical hypothyroidism and clinical hypothyroidism, the serum TSH levels were (17.01 ± 8.2 μU/l, 7.3 ± 2.0 μU/l respectively) significantly increased than the controls. In the clinical hypothyroidism and subclinical hypothyroidism, the serum free T3 (fT3) levels were (5.6 ± 0.68 pmol/l, 2.54 ± 0.43 pmol/l respectively) significantly increased than the controls. In the clinical hypothyroidism and subclinical hypothyroidism, the serum total T3 (T3) levels were (1.27± 0.24 nmol/l, 0.59±0.12 nmol/l respectively) significantly increased than the controls. The study results may conclude that, prolactin regulation is altered, in patients with clinical and subclinical hypothyroidism. Thyroid functions tests ought to be conducted in patients with hyperprolactinemia prior to performing further tests.

Risk of Nonalcoholic Fatty Liver Disease Is Associated with Urinary Phthalate Metabolites Levels in Adults with Subclinical Hypothyroidism: Korean National Environmental Health Survey (KoNEHS) 2012-2014.

Nonalcoholic fatty liver disease (NAFLD) is a condition of excess accumulation of fats in the liver. Thyroid dysfunction is commonly observed in adult populations with NAFLD. In subjects with thyroid dysfunction, phthalates, which are chemical compounds widely used to increase the flexibility of various plastic products, may increase the risk of NAFLD prevalence. Therefore, our study aimed to evaluate the relationship between the levels of urinary phthalate metabolites and the risk of NAFLD stratified by the levels of thyroid-stimulating hormone (TSH). Data (n = 2308) were obtained from the Korean National Environmental Health Survey II (2012–2014). Using the hepatic steatosis index, participants were classified into non-NAFLD (<30) and NAFLD (>36) groups. Participants with euthyroidism were defined as 0.45–4.5 mIU/L for serum TSH and normal thyroxine (T4) levels (n = 2125). Subclinical hypothyroidism (SCH) was defined as a higher TSH level (4.5–10 mIU/L) with normal total T4 levels in the serum (n = 183). A multivariate analysis was performed to assess the association of the urinary phthalate concentration with the risk of NAFLD after stratification based on the thyroid hormone levels. The levels of phthalate metabolites in urine were not significantly associated with NAFLD in adults with euthyroidism. However, a significant increased risk of NAFLD in those with SCH was observed in the fourth quartile of mono (2-ethyl-5-hydroxyhexyl) phthalate (odds ratio (OR) 13.59, 95% confidence interval (CI) 12.13–86.44), mono (2-ethyl-5-oxohexyl) phthalate (OR 8.55, 95% CI 1.20–60.53), mono-(2-ethyl-5-carboxypentyl) phthalate (OR 9.06, 95% CI 1.78–45.96), and mono-benzyl phthalate (OR 6.05, 95% CI 1.62–22.54) compared to those of the lowest quartile after being adjusted with covariates. In conclusion, the levels of phthalate metabolites in urine are positively associated with NAFLD in adults with SCH. More experimental studies are needed to clarify the risk of NAFLD caused by phthalate exposure in cases with poor thyroid function.

Wide Spectrum of Thyroid Function Tests in COVID-19: From Nonthyroidal Illness to Isolated Hyperthyroxinemia

BackgroundChanges in thyroid function test (TFT) in COVID-19 patients have been reported in several studies. However, some features such as thyrotoxicosis are inconsistent in these studies. In addition, some drugs such as heparin interfere with the free T4 assay.ObjectivesThis study was designed to examine TFT abnormalities in COVID-19, utilizing direct and indirect methods of free T4 assay.MethodsThis prospective cross-sectional study was conducted on 131 hospitalized COVID-19 patients. Serum levels of total T3, TSH, T3RU, and total T4 were measured. The free T4 assay was performed using direct (free T4) and indirect (free thyroxin index or FT4I) methods. The patients were categorized into different TFT groups. The clinical characteristics, laboratory findings, and outcomes were compared between the groups.ResultsThe frequencies of nonthyroidal illness (NTI), subclinical/overt hypothyroidism and subclinical/overt thyrotoxicosis were 51.7, 6.9, and 6.9%, respectively. Besides, 6 and 8.1% of the patients had isolated high free T4 and isolated high FT4I without any other TFT abnormality, respectively. The lymphocyte percent was lower in the subclinical/overt group than in other TFT groups (P = 0.002). Atrial Fibrillation (AF) was found in 37.5% of subclinical/overt thyrotoxicosis patients versus 1.7% in the NTI and nil in the other three groups (P < 0.001).ConclusionsIn addition to the reported TFT abnormalities in COVID-19 in previous studies, some new features like isolated hyperthyroxinemia were found in our study. We found a strong association between subclinical/overt thyrotoxicosis and AF. Regarding the high prevalence of AF in hospitalized COVID-19 patients, request for thyroid function test is rational in COVID-19 patients with this arrhythmia.

Subclinical Hypothyroidism in Families Due to Chronic Consumption of Nitrate-Contaminated Water in Rural Areas with Intensive Livestock and Agricultural Practices in Durango, Mexico

Nitrate is a widely disseminated water pollutant and has been linked to health disorders, including hypothyroidism. Here, we evaluated the relationship between thyroid function and chronic exposure to nitrates in rural zone families, in addition to the genetic and autoimmune factors. Exposure and effect biomarkers, thyroid hormones, and autoantibodies of tiroperoxidase were measured, as well the presence of two FOXE1 polymorphisms (rs965513, rs1867277). Pearson’s correlation, principal component analysis, Kruskal–Wallis, and chi-squared tests were used for statistical analysis. A total of 102 individuals were analyzed; 45% presented subclinical hypothyroidism, a negative correlation was observed between methemoglobin and the total T3 (r = −0.43, p = 0.001) and free T3 levels (r = −0.34, p = 0.001), as well as between TSH and the free T4 (r = −0.41, p = 0.0001) and total T4 (r = −0.36, p = 0.0001). A total of 15.7% had positive antithyroid ab-TPO, while the polymorphic genotype (AA) represented only 3% (rs965513) and 4% (rs1867277) among subjects with subclinical hypothyroidism. The high frequency of subclinical hypothyroidism in the population under study could be related, mainly, to chronic exposure through the consumption of nitrate-contaminated water.

Thyroid Dysfunction in Patients with Liver Cirrhosis and its Association with the Severity of Liver Disease: A Cross-sectional Study

Introduction: There exists a complex relation between the thyroid hormones and liver physiology in health and disease. The liver along with the thyroid gland play a significant role in the conversion of inactive Thyroxine (T4 ) to active Triiodothyronine (T3 ). The most common thyroid hormone profile in cirrhosis of liver is a low total T3 and free T3 , secondary to reduced activity of deiodinase type 1 and increased conversion to rT3 . Aim: To assess the association between the thyroid hormone levels and severity of liver disease, expressed in terms of child pugh score in tertiary care hospital in Goa. Materials and methods: The cross-sectional observational study included hundred patients with liver cirrhosis, admitted at a tertiary care hospital in Goa, from October 2019 to September 2020. The thyroid hormone levels were estimated from an early morning fasting blood sample within 24 hours of admission, once the patient satisfied the inclusion criteria. The Child Turgott Pugh scoring system was used to classify patients as per their severity of liver disease. The data was entered and analysed in Statistical Package for Social Sciences (SPSS) software version 14.0. Results: There were 95 males and 5 females. The study showed low mean levels of total T4 and free T3 in patients with cirrhosis of liver, which was significantly associated with Child Pugh classes of liver dysfunction. There was an association between levels of free T3 and the classes of Child Pugh score. The difference in the mean levels of TSH, total T3 and free T4 across the Child Pugh classes were not statistically significant. Conclusion: The study showed low free T3 levels in patients with cirrhosis of liver as seen in similar studies done in various settings. Thus, Thyroid Function Tests (TFTs) especially free T3 levels have a considerable potential to be used an independent predictor or a proxy to prognosis in patients with liver cirrhosis.

Effect of Pyrethroid on Fertility of Adult Rats

Sixty&nbsp; Adult female albino rats&nbsp; were randomly divided into seven groups as fellow group (1) normal control, Inductive group (1) in this group animals received low dose&nbsp; 12 mg/kg) from permethrin,&nbsp; Inductive group (2),in this group animals received high dose ( 75mg/kg.) from permethrin, group 4: treated group, animals received Vit E. (500 mg/ mg/Kg.) and then received low dose of permethrin (12 mg/k.) after half hour, group 5: treated group, animals received Vit E. (500 mg/ mg/Kg.) and then received high dose of permethrin (75 mg/k.) after half hour,Group 6: treated group, animals received Vit E. (250 mg/ mg/Kg) and then received low dose of permethrin (12 mg/k. ) after half hour and group 7: treated group, animals received Vit E. (250 mg/ mg/Kg.) and then received low dose of permethrin (75 mg/k. ) after half every doses received daily. At the end of the experimental period Blood samples were withdrawn,we determine triglyceride (TG), total cholesterol (TC), blood urea and creatinine. Also Estradiol and progesterone, total T3 , T4 and TSH levels&nbsp; in plasma of female were measured. The excised ovary in each group used to measure MDA, as a marker for lipid peroxidation (LPO) and GSH content in ovary tissue . In the same time the ovarian tissue which were&nbsp; removed after sacrifice,&nbsp; it was used for histological examination for the evaluation and assessment of the d fibrous formation, in injuries tissue. permethrin with different doses (12 and 75 mg/kg &nbsp;respectively) significantly (p≤ 0.05) increased the MDA &nbsp;and significantly decreased (p&lt; 0.05) in GSH content in ovary tissue versus control animal. Though treatment with vitamin E after permethrin with different dose (250 and 500 mg/kg respectively) significantly deceased the MDA content versus permethrin group (12 and 75 mg/kg&nbsp; respectively) and Vit E treatment increased GSH content in a group treated with (permethrin 75 mg/kg b.w). The level of both serum estrogen (E2) and progesterone were significantly (p&lt;0.05) decreased in a permethrin group in both doses (12 and 75 mg/kg ) when compared to control group. While, treatment with Vit E ameliorate the level of E2 and progesterone. Treating rats with permethrin led to a significant decrease in triiodothyronine (T3) and thyroxine (T4) as well as a significant increase of thyroid-stimulating hormone (TSH) when compared to control group. Administration of Vitamin E and permethrin caused an improvement in the levels ofT3 and T4 and TSH. This study was designed to elucidate premethrin effects at doses (12and75mg\kgw b) for 30 days, causing reproductive toxicity through several biotransformation metabolites processes. Focusing on ovarian injures and reproductive efficacy. treated ovarian tissue showed histological alterations represented by reduction number of different follicles, with absent mature follicles in high dose premethrin, or follicles without oocytes&nbsp; and zone granulose residual with vacuolar change finally necrotic areas. Special stain for connective tissue fibersMasson's&nbsp; trichrome, showed accumulation of fibrous proportional to the dose. while the Immuno- reactive of TNF-ᾳ assayment many necrotic area evidence of premethrin toxicity, also its dwindling effect on proliferating cell nuclear antigen (PCNA)which affected the efficiency of DNA, and consequently on the cell proliferative activity. In contrast, evaluate the effective therapeutic role of Vitamin E at doses (250 and 500 mg \kg bw),as an antioxidant clarified, which is explained by the&nbsp; histological in the results.&nbsp; This study reveals that chronic exposure to premerthin even&nbsp;&nbsp; low dose alters ovarian cycle&nbsp; activity . Hence, Premethrin exposure threat&nbsp; fertility of humans and&nbsp; animals.it is speculate that the positive effect of the Vitamin E by its antioxidant activity able to protect ovarian tissues the premerthin toxicicity

Thyroid Disorders.

Thyroid Disorders.

Association of Phthalate Exposure with Thyroid Function and Thyroid Homeostasis Parameters in Type 2 Diabetes.

Aims Phthalates, which are recognized environmental endocrine-disrupting chemicals, are associated with thyroid hormone disruption. We aimed to evaluate the relationship of phthalate metabolites with thyroid function and thyroid homeostasis parameters in type 2 diabetes and to explore whether thyroid autoimmunity status and metformin, the most common antidiabetic drug, may influence such associations. Methods Concurrent urine and blood samples were collected from 639 participants with type 2 diabetes in the METAL (Environmental Pollutant Exposure and Metabolic Diseases in Shanghai) study. We measured urinary concentrations of thirteen phthalate metabolites along with serum levels of thyroid-stimulating hormone (TSH), total T4 and T3, free T4 (FT4) and T3 (FT3), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb). Four parameters of thyroid homeostasis, including the sum activity of step-up deiodinases (SPINA-GD), thyroid secretory capacity (SPINA-GT), Jostel's TSH index (TSHI), and thyrotroph thyroid hormone resistance index (TTSI), were also calculated. Results Among all participants, after full adjustment, multivariable regression analysis showed that some urine phthalate metabolites were negatively associated with TSH, TSHI, and TTSI levels and positively associated with FT3, T3, SPINA-GD, and SPINA-GT levels. None of the urine phthalate metabolites exhibited a significant association with thyroid autoimmunity. The associations of phthalate metabolites with thyroid function and thyroid homeostasis parameters differed based on thyroid autoantibody and metformin treatment status. Conclusions Urinary phthalate metabolites may be associated with thyroid function and thyroid homeostasis parameters among participants with type 2 diabetes. Furthermore, our present study suggested that thyroid autoantibody status and metformin treatment status are potential mediators of such associations.

Thyroid Dysfunction as a Modifiable Risk Factor for Wet Type Age-Related Macular Degeneration: A Case-Control Study.

Purpose:To investigate possible links between thyroid dysfunction and prevalence of wet age-related macular degeneration (AMD).Methods:The present case–control study enrolled a total number of 90 patients with wet AMD and 90 sex-, and age-matched controls through a convenient sequential sampling method. Thyroid hormones were profiled in serum assay. Statistical measures were done to compare means between groups.Results:Our findings showed a significant difference in free T4 levels between wet AMD and control groups (P = 0.002), but the mean values of total T3 and Thyroid-stimulating hormone levels were similar between the two groups. In addition, there were no differences in serum lipid profile between groups. Although no significant difference in the history of hypertension and hyperlipidemia between wet AMD and control groups was found, the history of smoking was higher in controls (P = 0.039).Conclusion:Thyroid hormone abnormalities may be associated with wet AMD.

The Association between the Dietary Inflammatory Index and Thyroid Function in U.S. Adult Males

Thyroid function has a close link with inflammation. However, it is still unknown whether the dietary inflammatory potential is associated with thyroid function. We aimed to assess the relationship among them using the data from the National Health and Nutrition Examination Survey (NHANES). This study was a cross-sectional study, where weighted multivariable linear regression, subgroup analyses, and interaction terms were employed. Thyroid function was assessed by eight indexes, including total and free T4 and T3, Tg, TgAb, TPOAb, and TSH. A total of 2346 male participants aged ≥20 years with an average age of 50.74 ± 17.68 years were enrolled. The mean DII score among participants was −0.46 ± 1.73, ranging from −4.12 to 4.41, and mean total thyroxine (T4) was 7.61 ± 1.51 μg/dL. We found a positive association between DII and total T4 (β = 0.07; p = 0.0044). Using subgroup analysis, this association became stronger in both the iodine-deficient and obese group (iodine-deficient group: β = 0.15, p < 0.0001; obese group: β = 0.14, p < 0.0001). In conclusion, men adhering to a more pro-inflammatory diet appeared to have higher total T4 levels. However, these hormone variations were still within the normal clinical range and more well-designed studies are still needed to validate the causal relationship between DII and thyroid function.

Maternal and Newborn Thyroid Hormone, and the Association With Polychlorinated Biphenyls (PCBs) Burden: The EHF (Environmental Health Fund) Birth Cohort.

Background: Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants found in human tissues. PCBs can be transferred through the placenta and may disrupt the maternal thyroid homeostasis, and affect fetal thyroid hormone production. Several studies have shown that intrauterine exposure to PCBs might be associated with abnormal levels of thyroid hormones in mothers and their offspring.Objectives: To examine the associations between environmental exposure to PCBs and thyroid hormone levels in mothers and newborns.Methods: The EHF-Assaf-Harofeh-Ichilov cohort includes 263 mothers-newborns dyads. A total of 157 mother-newborn dyads had both PCBs and thyroid function measures. Regression models were used to estimate associations between maternal PCB exposure and maternal and newborn thyroid function, controlling for possible confounders.Results: Four PCBs congeners were analyzed: PCBs 118, 138, 153, and 180. ∑PCBs median (IQR) level was 14.65 (2.83–68.14) ng/g lipids. The median maternal thyroid-stimulating hormone (TSH) level was 2.66 (0.70–8.23) μIU/ml, the median maternal free thyroxine (FT4) level was 12.44 (11.27–13.53) μg/dL, the median maternal thyroid peroxidase antibodies (TPO Ab) level was 9.6 (7.36–12.51) IU/mL. Newborns' median total thyroxine (T4) level was 14.8 (7.6–24.9) μg/dL. No association was found between exposure to different congeners or to ∑PCBs and maternal TSH, FT4, thyroglobulin autoantibodies (Tg Ab), TPO Ab and newborn total T4 levels. In multivariable analysis a 1% change in ∑PCBs level was significantly associated with a 0.57% change in maternal TSH levels in women with body mass index (BMI) < 19. The same association was observed for each of the studied PCB congeners. Maternal TPO Ab levels statistically significantly increased by 0.53 and 0.46% for 1% increase in PCB 118 and 153 congeners, respectively. In women with BMI > 25, the association between the PCBs levels and maternal TSH levels was in the opposite direction. No association was found in women with normal BMI (19–24.9).Conclusions: Background exposure to environmentally relevant concentrations of some PCBs can alter thyroid hormone homeostasis in pregnant women and might be associated with abnormal TSH levels and TPO-Ab in women with low BMI. However, these findings require further investigation.

Colorectal cancer causes alteration of thyroid hormone profile in newly diagnosed patients

ABSTRACT Objectives Subcellular alteration of thyroid hormones (THs) signaling is proposed in many types of cancers. Some studies show deiodinase type 3, as an oncofetal protein, re-expresses in some cancer types. Therefore, we aimed to investigate the product of this enzyme, reverse triiodothyronine (rT3) in serum of newly diagnosed colorectal cancer (CRC) patients. Methods In this cross-sectional study, blood from 38 laboratory-confirmed cases was taken, and serum levels of rT3, total T3 (triiodothyronine), total T4 (thyroxine), free T3, free T4, and thyroid-stimulating hormone (TSH) were detected by using an enzyme-linked immunosorbent assay. Results The results illustrated that rT3 and free T3 levels increased in patients with early stages of colorectal cancer, despite normal levels of total T3, total T4, free T4, and TSH. Conclusion The elevation of rT3 in CRC patients can probably be due to the re-expression of deiodinase type 3 in CRC. Further research is needed to study the role of intracellular THs modulation in CRC and its impact on CRC treatment.

Exposure to Multiple Per- and Polyfluoroalkyl Substances In Relation To Thyroid Function Among Adolescents and Young Adults from NHANES 2011-2012

BACKGROUND AND AIM: Per- and polyfluoroalkyl substances (PFASs) are persistent chemicals with a wide range of industrial applications, measured in human serum samples. Experimental studies have identified PFASs as endocrine disrupting chemicals and epidemiological studies suggest that PFASs can affect normal thyroid function in humans. We investigated the association between exposure to mixtures of serum PFASs and changes in serum thyroid hormone levels among 12 to 20 year olds. METHODS: Using data from the NHANES 2011-2012 cycle, we employed principal component analysis (PCA) and identified three factors, describing mixtures of PFASs. Using multivariable linear regression models, we estimated associations between exposure to PFAS mixtures and changes in serum thyroid hormone concentrations. RESULTS:Factor 1 was characterized by carboxylates, comprising of PFUnA, PFDA, and PFNA, Factor 2 was described by sulfonates which included PFHxS, PFOS, PFA, and MeFOSAA and Factor 3 was described PFHpA alone. Greater exposure to Factor 1 PFASs was associated with an overall increase in free T4, TSH, and thyroid peroxidase antibodies levels, without any statistical significance. Exposure to Factor 2 PFASs was associated with an overall decrease in free T3, total T3, free T4, and total T4 levels. Factor 3 resulted in an increase in most of the serum thyroid hormone levels with the exception of thyroglobulin and thyroglobulin antibodies levels. CONCLUSIONS:Our results suggest the importance of modeling the effects of exposure to a mixture of PFASs simultaneously. The findings of this analysis can better inform researchers and policy makes on which PFASs behave analogously or inversely in an effort to better assess the effect PFASs may have on health effects. KEYWORDS: biomarkers, chemical mixtures, endocrine disruptors, polyfluoroalkyl substances, thyroid function

Overtreatment of Transient Maternal Hyperthyroidism Resulting in Fetal Goiter.

Overtreatment of Transient Maternal Hyperthyroidism Resulting in Fetal Goiter.

The Correlation Between Low Serum T3 Levels and All-Cause and Cardiovascular Mortality in Peritoneal Dialysis Patients.

ObjectiveThis study is to investigate the correlation between serum triiodothyronine (T3) levels and all-cause and cardiovascular mortality in PD patients.MethodsA total of 376 end-stage renal disease (ESRD) patients who started maintenance PD treatment in the Department of Nephrology in our hospital and stable treatment for ≥3 months were selected, and the total T3 (TT3) and free T3 (FT3) levels were determined. Among them, 168 cases with FT3 <3.5 pmol/L and/or TT3 <0.92 nmol/L were divided into the low serum T3 level group, and the remaining 208 cases were divided into normal serum T3 level group. The Cox survival analysis method was used to analyze the correlation between low serum T3 levels and all-cause and cardiovascular mortality in PD patient.ResultsCompared with the normal serum T3 level group, patients with low serum T3 levels had higher systolic blood pressure and a higher proportion of heart disease, and lower levels of total T4, free T4, hemoglobin, serum albumin, blood calcium, serum total bilirubin, alanine aminotransferase, and 24-h urine volume (all P < 0.05). Binary Logistic regression analysis showed that heart disease (P = 0.003, OR: 2.628, 95% CI: 1.382–4.997) and high TT4 level (P < 0.001, OR: 0.968, 95% CI: 0.956–0.979) were related to low serum T3 levels in PD patients. Multivariate Cox regression analysis showed that low serum FT3 level was an independent risk factor for all-cause death in PD patients (HR = 0.633, 95% CI = 0.431–0.930; P < 0.020).ConclusionLow serum T3 levels in PD patients were associated with heart disease and TT4 levels. Low serum FT3 levels were associated with the risk of all-cause death in PD patients.

Comparison of Serum Thyroid Hormone Levels in Green-winged Macaws (Ara chloropterus) Using Radio and Chemiluminescent Immunoassays.

This study compared the use of radioimmunoassay (RIA) and chemiluminescent immunoassay (CLIA) to measure serum thyroid hormone levels in green-winged macaws (Ara chloropterus). The sample group comprised 20 male and 13 female (n = 33) healthy, captive green-winged macaws of reproductive age but outside of breeding season. Mean free triiodothyronine (T3), total T3, and free thyroxine (T4) measured by CLIA and RIA corresponded to 5.11 and 5.08 pmol/L (3.33 and 3.31 pg/mL), 1.59 and 1.56 nmol/L (103.5 and 101.5 ng/dL), and 8.25 and 8.82 pmol/L (0.64 and 0.69 ng/dL), respectively. Mean total T4 by RIA corresponded to 6.29 nmol/L (0.49 µg/dL). Mean free T4 and thyroid-stimulating hormone (TSH) levels differed according to immunoassay method, with higher values measured by RIA compared with CLIA. Sex influence was statistically significant in immunoassay results only on free T3 levels. Free T3 levels measured by RIA were higher than levels measured by CLIA in male birds, but this difference was not found with the female bird samples. Conversely, free T3 levels measured by CLIA were higher in the female macaws compared with male birds. Comparative analysis of thyroid hormone measurements in this study revealed that RIA and CLIA are equivalent methods to measure free T4 and total T3 levels but not TSH levels. These findings support the use of CLIA for free T4 and total T3 level determinations in green-winged macaws. However, the CLIA kit used in this study provided invalid total T4 level results for the macaws sampled. Radioimmunoassay and CLIA were equally ineffective for determining TSH levels in this species.

A prospective study on thyroid functions in chronic kidney disease patients: In tertiary care centre

Background and Objectives: Unusual thyroid function tests are frequent in chronic kidney disease patients. The kidneys play an important role in thyroid hormone metabolism by converting T4 to T3 (the active metabolite). Low plasma free T3 in ESRD is a marker of inflammation and endothelial activation, and it has been linked to an increased risk of death from any cause. The present study has been conducted to look for biochemical abnormalities in thyroid function tests in chronic kidney disease, as well as to correlate the severity of CKD and changes in thyroid indices. Methods: In a cross-sectional study, thyroid function tests [TT3, TT4, FT4, TSH] were estimated by CLIA in 60 patients of chronic kidney disease who were in various stages. Symptoms of hypothyroidism, thyroid hormone abnormalities and CKD stage were analyzed using Chi-square test and ANOVA tests. Results: Among the mean age was 48.8 ± 12.2 years, of which 38 were male and 22 females. The mean value of TT3 in CKD stage 3, 4, 5 were 1.01±0.39; 1.05± 0.6; 0.95±1.09 µg/mL respectively. (p= 0.02 Significant). The mean value of TT4 in CKD stage 3, 4, 5 were 6.3± 2.4; 5.5± 1.5; 5.11 ± 1.01 µIU/ml, respectively. (p=0.71 Not significant). Conclusions: Total T3 and total T4 levels were found to decrease progressively as the stage of CKD increased. There was no statistically significant relationship between TT4 and CKD stage. The prevalence of thyroid dysfunction and the stage of chronic kidney disease were found to be significantly related. The severity of renal failure increases the prevalence of thyroid hormone abnormalities; the levels of thyroid profile, i.e. T3, T4, and TSH, decrease as the severity of renal failure increases. Thyroid hormone abnormalities could represent a risk factor for cardiovascular disease and might also be implicated in kidney disease progression.

High Incidence of Hypothyroidism Within a Month in Neonates with Down Syndrome Who Are Euthyroid at Birth: Results of A Prospective Study

The objective was to test for hypothyroidism (HYT) in infants with Down Syndrome (DS) who tested euthyroid on state newborn screening for congenital HYT. In 39 infants with DS who were euthyroid at birth, serum TSH, total T4 (TT4) and free T4 (FT4) levels were measured during 15 to 120 days of age. TSH, TT4 and FT4 were measured by standard techniques. Depending up on age specific TSH and thyroid hormone (TH) levels, babies were classified as: Euthyroid (normal TSH and normal TH), Primary HYT (high TSH and low TH), compensated HYT (high TSH and normal TH) and sick thyroid (low TSH and low TH). Comparisons among different groups were performed using two-sample t-tests. Twenty-nine babies (72%) remained euthyroid (TSH 6.1 ± 2.6 mIU/ml, TT4 10.8 ± 1.8 µg/ dl and FT4 1.57 ± 0.4 ng/dl). Six (18%) babies developed primary HYT (TSH 23.5 ± 10, TT4 5.1 ± 1.2, FT4 1.17 ± 0.2) within a month of life needing T4 therapy. While 4 (10%) babies developed compensated HYT (TSH 29.3 ± 10, TT4 10.6 ± 3.6 and FT4 1.83 ± 0.3), one (2.5%) had sick thyroid syndrome (TSH 4.6, TT4 4.6 and FT4 1.1). All four babies with compensated HYT were euthyroid by four months of age. Despite normal newborn screening at birth, the incidence of any HYT was much higher (28 %) than the normal neonatal population (1/2000-4000). More importantly, HYT developed within a month of age. Recommendations by the AAP about retesting TH function in infants with DS should be revised.

THYROID HORMONE ABNORMALITY IN PATIENTS WITH ACUTE STROKE- A HOSPITAL BASED CASE CONTROL STUDY

Introduction: Stroke or Cerebrovascular accident (CVA) is a major cause of disability worldwide. The estimation of serum Total T3, Total T4 and TSH are very much essential in patients with stroke. Any disturbances in thyroid hormones may have negative influence on the outcome of acute phase of strokes. Aims And Objectives: Aims and objective was to estimate the Total T3, Total T4 and TSH of patients with acute Stroke and to compare it with age/sex matched healthy controls. Materials &amp; Methods: This Hospital Based Case Control Study, consist of total 100 subjects out of which 50 were control ,was carried out in Jorhat Medical College &amp; Hospital, Assam for a period of one year, from July 2017 to June 2018. Age more than 40 years of both sexes was included. Estimation for total T3, total T4, and TSH was carried out in Access 2 ImmunoAssay Systems (Beckman Coulter). Cases were selected randomly . Results And Observations: Out of 50 Stroke patients ,the age group of 50 - &lt;60 years constituted the majority of cases(32%) . Greater preponderance of stroke was seen in males (62%) with male to female ratio of 1.63:1. Hemorrhagic stroke was found to be more common than ischemic stroke (54% V/s 46%). Hemorrhagic strokes occurred more in early age than ischemic strokes. The mean ± SD of serum Total T3 levels in stroke patients and controls were 0.960 ± 0.327 and 1.248 ± 0.269 respectively, with statistically significant mean value difference (p&lt;0.05) when cases were compared to the controls. A greater number of low T3 was present in ischemic strokes (43.5%) when compared to hemorrhagic strokes (18.5%). Conclusion: Nonthyroidal illness syndrome (Low T3 syndrome) is observed in the present study with decreased T3 values without alteration of T4 and TSH levels. Further studies with a large sample size should attempt to investigate whether treatment of low T3 syndrome can improve the final outcome.

Effects of oral versus transdermal estradiol plus micronized progesterone on thyroid hormones, hepatic proteins, lipids, and quality of life in menopausal women with hypothyroidism: a clinical trial.

The aim of the study was to evaluate the effects of usual doses of oral estradiol with transdermal estradiol and the effects of these estrogens plus micronized progesterone (MP) in menopausal women with primary hypothyroidism. Twenty women were randomized to 12 weeks of treatment with estradiol 1 mg tablets or estradiol 1 mg gel. Then, women with a uterus received a 100 mg capsule of oral MP. Thyroid function, thyroxine-binding globulin (TBG), sex hormone-binding globulin (SHBG), insulin-like growth factor 1 (IGF-1), lipid profiles, and quality of life were measured at baseline and after 12 and 24 weeks. Oral estradiol led to an increase in total T4 levels (5.84 ± 1.11 vs 8.41 ± 1.61 μg/dL; P < 0.001); changes in thyroid-stimulating hormone (TSH) levels were clinically important in 3 of 10 participants who needed to increase their dose of levothyroxine. Significant changes were detected in hepatic proteins with oral estradiol: TBG and SHBG levels increased (15.29 ± 3.87 vs 20.84 ± 5.49 μg/mL, P < 0.001; 61.85 ± 33.6 vs 121.4 ± 49.36 nmol/L, P < 0.001; respectively), whereas IGF-1 levels decreased (152 ± 38.91 vs 96 ± 17.59 ng/mL; P < 0.001). Transdermal estradiol alone did not significantly affect the thyroid function. Transdermal estradiol plus MP led to a decrease in TSH levels (1.79 ± 1.05 vs 1.09 ± 0.52 mIU/L; P = 0.04), while total T4 levels increased (7.54 ± 1.34 vs 9.95 ± 2.24 μg/dL; P = 0.01). Hormonal therapy had a greater impact on depressed mood and vasomotor symptoms. Total T4 and TBG levels increase after oral estradiol in women with hypothyroidism and it may cause clinical changes in TSH levels. Conversely, transdermal estradiol alone or plus MP does not cause major changes in thyroid function in these women.