Free T4 Research Articles

Comparison of Enzyme-Linked Immunosorbent Assay and Lateral Flow Assay to Measure Thyroid-Stimulating Hormone and Free T4 in Human Serum.

Thyroid disorders affect millions of people around the world, mainly women. Measurement of hormones is critical in their identification, treatment, and monitoring; Therefore, the methods must be as reliable and valid as possible. We designed a cross-sectional study to compare thyroid-stimulating hormone (TSH) and free tetraiodothyronine (fT4) concentrations using ELISA (Enzyme-Linked Immunosorbent Assay) and LFA (Lateral Flow Assay) in human serum samples. We obtained 96 serum samples that were evaluated with a commercial kit for ELISA (Accubind Monobite, Lake Forest, California, US) and LFA (Micropofit Fluorecare, Guangdong, Shenzhen, China). We used the Wilcoxon nonparametric test, Bland-Altman, and Passing-Bablok regression to compare TSH and fT4 concentrations obtained by ELISA and LFA. The median TSH concentrations obtained by ELISA and LFA were 1.92 and 2.11 μIU/mL, and for fT4 were 1.14 and 1.10 ng/dL. On the other hand, the Spearman's rho between ELISA and LFA for TSH was 0.845. The TSH concentrations between ELISA and LFA had significant differences (p < 0.05). About fT4, the Spearman's rho between methods was 0.348. The bias for TSH was -0.315, and for fT4 was -0.013. The Deming regression for TSH (p = 0.309) and fT4 (=0.938) shows that the levels obtained by both methods do not present significant differences, and the Passing-Bablok regression identifies significant bias between both methods, especially for fT4, in the range of concentrations studied. TSH measurement by LFA may be a viable alternative to evaluate thyroid diseases, but fT4 by LFA is not precise and presents a high bias.

Uncovering non-autoimmune hypothyroidism: A case report of rhabdomyolysis and myocarditis mimicking acute coronary syndrome.

Non-autoimmune hypothyroidism is a rare but significant cause of rhabdomyolysis and myocarditis, which can mimic acute coronary syndrome. Early recognition and treatment of hypothyroidism are crucial, especially in patients with chronic kidney disease (CKD), where delayed diagnosis may lead to life-threatening complications such as acute kidney injury. A 71-year-old male with diabetes, CKD stage G3aA3, and a history of chronic myelogenous leukemia presented with myalgia, anorexia, and anuria. He also reported intermittent chest pain for 1 month, progressing to severe symptoms including decreased urine output and anuria. Laboratory findings revealed acute kidney injury (serum creatinine: 12.14 mg/dL), extreme elevations in muscle enzymes (creatine kinase: 250,000 IU/L), and cardiac biomarkers (troponin-T: 543 ng/L). Initial management did not improve his condition. On day 15, thyroid function tests confirmed non-autoimmune hypothyroidism (TSH: 55.58 μIU/mL, free T4: 0.06 ng/dL). The patient underwent hemodialysis and conservative treatment initially, followed by levothyroxine replacement therapy on day 16. Renal function, urine output, and muscle enzyme levels gradually improved after thyroid hormone supplementation. By discharge on day 40, the patient's serum creatinine decreased to 3.08 mg/dL, and hemodialysis was discontinued. At 7 months posttreatment, his renal function stabilized at CKD stage G3bA2 with normal thyroid function. This case highlights the importance of considering hypothyroidism in patients with unexplained rhabdomyolysis and persistent cardiac symptoms, particularly in those with CKD. Early thyroid function testing can lead to timely treatment and improved outcomes in such complex cases.

Commercially available recombinant human thyroid-stimulating hormone effectively stimulates total and free thyroxine concentrations in Quaker parrots (Myopsitta monachus), including at low doses and after freezing.

To develop a protocol for thyroid-stimulating hormone (TSH) stimulation testing in psittacine birds using thyrotropin alfa (Thyrogen; Sanofi). Quaker parrots (Myopsitta monachus) were randomized to receive an IM injection of freshly reconstituted high-dose recombinant human TSH (rhTSH; 8 parrots), frozen high-dose rhTSH (8), frozen low-dose rhTSH (8), or saline (8). Total T4 (TT4), free T4 (FT4), T3, and TSH were measured pre- and 4 hours postinjection. TSH stimulation testing was completed in 31 of the 32 birds. Thyroid-stimulating hormone measurement confirmed proper administration of rhTSH. Median TT4 at baseline in the population was 0.14 μg/dL (range, 0.03 to 0.33 µg/dL). Poststimulation, the median TT4 in rhTSH-treated parrots was 1.31 µg/dL (0.29 to 1.98 µg/dL) versus 0.09 µg/dL (0.04 to 0.14 µg/dL) in control parrots. All parrots administered rhTSH had an increase in TT4 (minimum, 3.5-fold) and FT4 (minimum, 2.2-fold) from baseline but not in T3. Parrots administered saline had no increase in TT4, FT4, or T3. Postinjection concentrations of TT4, but not of FT4 or T3, showed no overlap between controls and rhTSH-treated parrots. TSH stimulation testing performed with fresh and frozen rhTSH for 3 months is feasible and safe and results in a significant increase in TT4 in Quaker parrots. Total T4 should be the preferred outcome measure for TSH stimulation testing in parrots. Thyrogen can be used at doses as low as 0.01 mL (73 µg/kg) for TSH stimulation tests in Quaker parrots and can be frozen in aliquots to perform more tests per vial.

Comparison of the newly formulated beckman access free T4 (Thyroxine) assay on the DXI 800 analyzer with the current Beckman free T4 (Thyroxine) assay for biotin Interference: New assay is free from biotin interference.

Comparison of the newly formulated beckman access free T4 (Thyroxine) assay on the DXI 800 analyzer with the current Beckman free T4 (Thyroxine) assay for biotin Interference: New assay is free from biotin interference.

Role of thyroid antibodies in the diagnosis of thyroid eye disease

Background Thyroid eye disease (TED) is an autoimmune disorder caused by autoantibodies targeting thyroid-stimulating hormone (TSH) receptors. Aim To correlate the clinical profile of TED with the level of circulating biomarkers [TSH receptor antibody and antithyroglobulin antibody (anti-TgAb)]. Patients and methods A prospective observational cross-sectional study carried out on 40 TED patients. The patients were subjected to full history taking, endocrinological evaluation, and full ophthalmological examination. All the participants underwent thyroid function tests (TSH, free T3, and free T4), autoantibody tests such as TSH receptor-stimulating antibody (TSAb) and anti-TgAb. Results A significant positive correlation was observed between TSH receptor antibodies and proptosis. TSAb were significantly higher among moderate to severe TED patients compared with those with mild disease. There was a statistically significant positive correlation between TSAb and severity of TED. Conclusion TSAb is indicative of TED with TSAb titers in serum positively correlating with activity and severity of TED. Anti-TgAb has a negative relationship with TED activity and severity.

The correlation between thyroid status parameters and prolactin levels in reproductive-age women with autoimmune thyroiditis and subclinical hypothyroidism

Background. Patients with primary hypothyroidism often exhibit elevated thyrotropin-releasing hormone levels, potentially leading to hyperprolactinemia, which manifests as galactorrhea-amenorrhea. However, data on prolactin (PRL) content in subclinical hypothyroidism are inconsistent due to variations in study populations, sample sizes, and methodologies. In some studies, it has been found that hyperprolactinemia is a rare disorder in subclinical hypothyroidism, but there are reports of its fairly high prevalence in subclinical hypothyroidism — in 0–40 % of patients. This study purposed to assess PRL levels in reproductive-age women with autoimmune thyroiditis (AIT) and investigate correlations between PRL and thyroid hormone levels. Materials and methods. PRL level was analyzed in women with AIT in states of euthyroidism and subclinical hypothyroidism. Results. Findings revealed significantly elevated PRL in women with AIT compared to controls (18.24 ± 1.61 vs. 12.24 ± 1.64 ng/mL; p &lt; 0.05). A Spearman regression analysis identified a significant negative correlation between PRL and free thyroxine (Spearman R = –0.27; p = 0.043), indicating a stronger association than between PRL and thyroid stimulating hormone (TSH). Analysis of PRL content depending on TSH levels showed that PRL significantly differed in patients with euthyroidism and subclinical hypothyroidism on the background of AIT (16.48 ± 1.46 vs. 25.45 ± 5.29 ng/ml; p &lt; 0.05). No differences in PRL levels were observed among euthyroid patients with AIT based on TSH levels. Conclusions. PRL levels were significantly higher in women with AIT than in controls (18.24 ± 1.61 vs. 12.24 ± 1.64 ng/mL; p &lt; 0.05). Women with subclinical hypothyroidism and AIT had significantly higher PRL levels than euthyroid women with AIT (25.45 ± 5.29 vs. 16.48 ± 1.46 ng/mL; p &lt; 0.05). No statistically significant changes in prolactin levels were observed in patients with autoimmune thyroiditis and euthyroidism in TSH levels above 2.5 mIU/L compared to the control group (p &gt; 0.05). A significant negative correlation between PRL and free T4 (Spearman R = –0.27; p = 0.043) indicates a more sensitive relationship compared to that between PRL and TSH.

Spectrum of Thyroid Disorders in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory arthritis involving 0.5-1% of the global population. Coexistence of RA and thyroid dysfunction is now increasingly being recognized. This is due to the shared factors involved in the pathogenesis of RA and autoimmune thyroid disease. Thyroid disorder is an important amplifier of disease activity, thereby impairing the quality of life. To study the prevalence and pattern of thyroid dysfunction in RA patients, to compare the disease activity among RA patients with thyroid dysfunction and those without thyroid dysfunction, and to study the possible association between severe RA and thyroid dysfunction. A hospital-based analytical cross-sectional study was done in 165 RA patients attending the General Medicine and Rheumatology outpatient facilities of the Department of General Medicine, Government Medical College, Kozhikode, from January to December 2019. Study subjects were selected based on the inclusion and exclusion criteria. Relevant investigations were done, which included serum thyroid stimulating hormone (TSH), free thyroxine (free T4), free triiodothyronine (free T3), and anti-thyroid peroxidase antibody (anti-TPO) antibody levels. Data were analyzed using MS Excel and Statistical Package for the Social Sciences (SPSS) software. The prevalence and pattern of thyroid disorders in RA patients were assessed. The association of thyroid dysfunction with disease activity was tested. The prevalence of thyroid dysfunction among RA patients was 38.2%. The most common thyroid disorder observed was subclinical hypothyroidism, which was seen in 33.3% (55) of the study population, followed by overt hypothyroidism in 3.6% (6) of patients. Both subclinical hyperthyroidism and clinical hyperthyroidism were found in only 0.6% of RA patients. There was a significant difference in mean age between RA patients with thyroid dysfunction and euthyroid patients (p-value = 0.001). No significant association was found between the duration of RA and thyroid dysfunction (p-value = 0.253). RA patients with thyroid dysfunction had elevated inflammatory markers compared to those with normal thyroid function. The prevalence of autoimmune thyroid disorder in RA patients is 24.8%. There was a significant association between disease activity and thyroid dysfunction (p-value = 0.001). Patients with thyroid disorders had severe disease compared to euthyroid patients. A significant positive correlation was noted between serum TSH and Disease Activity Score-28 (DAS-28) (Pearson coefficient = 0.768, p-value = 0.000), and between anti-TPO antibody and DAS-28 (Pearson coefficient = 0.794, p-value = 0.000). Thyroid dysfunction is prevalent in 38.2% of RA patients, with subclinical hypothyroidism being the most common thyroid disorder encountered. RA patients with thyroid dysfunction had higher disease activity than euthyroid patients. Hence, thyroid function tests should be a routine investigation in all RA patients, and if found abnormal, they should be treated appropriately.

Severity of thyrotoxicosis is a risk factor for excessive weight gain in treated hyperthyroidism.

Hyperthyroidism is characterized by weight fluctuations and overshoot of weight regain following treatment. We aimed to identify parameters predicting peak weight gain (PWG) in the post-treatment period. We included 110 patients (73 [66.4%] women) with hyperthyroidism 6-36 months after treatment initiation. The primary outcome was PWG of ≥10% (Group A) or <10% (Group B). We performed adjusted analyses by logistic regression with age, sex, disease-related weight loss, hypothyroidism occurrence, free T4 at diagnosis (fT4-t0) and disease duration as independent variables. Post-treatment mean (SD) weight gain was 7.4 (5.22) kg, whereas the disease-related weight loss was 5.3 (5.15) kg. Group A (52.7% participants) compared to Group B had significantly higher median (IQR) fT4-t0 at 47.4 (36.2, 97.2) vs. 29.3 (22.8, 40.4) ng/dl (p<0.001) and disease-related weight loss at 6.8 (3, 10) vs. 2.5 (0, 4.8) kg (p<0.001), and non-significantly higher presentation free triiodothyronine at 19.6 (10.4, 44.1) vs. 11.8 (8.7, 22.9) pg/ml (p=0.078) and TRAb at 6.3 (3, 16.1) vs. 4.2 (2.4, 8.7) IU/L (p=0.093), respectively. Significant predictor variables of post-treatment PWG in logistic regression were disease-related weight loss (OR=1.23, p=0.002) and fT4-t0 (OR=1.04, p=0.008). More than half the patients with hyperthyroidism had ≥10% PWG post-treatment. Indicators of disease severity, namely disease-related weight loss and baseline thyroid hormones, were predictive of excessive weight gain post-treatment and could be utilized for risk stratification and early intervention.

Association between anti-thyroid peroxidase antibody and insufficient sleep in euthyroid population.

Association between anti-thyroid peroxidase antibody and insufficient sleep in euthyroid population.

Panhypopituitarism Presenting with Non Specific Symptoms in a Geriatric Patient: A Case Report

Panhypopituitarism is a rare condition in which there is a deficiency of all the hormones released by the pituitary gland. It can occur at any age, from infants and children to adults. The pituitary hormones are responsible for several important functions in the body, such as metabolism, growth and reproduction. A 71-year-old female presented with symptoms of nausea, aversion to food and significant weight loss over the past month. Her past medical history included spine surgery five years ago, a hysterectomy 35 years ago and she was a known case of systemic hypertension. Initial evaluations revealed normal vital signs and stable cardiovascular and respiratory functions, but laboratory tests showed markedly low levels of Thyroid Stimulating Hormone (TSH), free T4, cortisol, Adrenocorticotropic hormone (ACTH), Follicular Stimulating Hormone (FSH) and Luteinising Hormone (LH). A brain Magnetic Resonance Imaging (MRI) revealed pituitary hyperplasia without focal lesions, leading to a diagnosis of panhypopituitarism, characterised by central hypothyroidism, adrenal insufficiency and gonadotropin deficiency. The diagnosis of panhypopituitarism in this case was challenging due to the non specific nature of the presenting symptoms. The patient’s hormonal profile revealed deficiencies in multiple pituitary hormones, which aligned with the diagnosis of panhypopituitarism secondary to pituitary hyperplasia. Treatment with intravenous hydrocortisone and thyroid hormone replacement therapy was initiated, resulting in significant clinical improvement. Timely hormone replacement therapy led to favourable outcomes. Long-term follow-up is crucial to ensure continued hormone balance and prevent complications.

Investigation of predictive parameters for recurrence in patients undergoing electrical cardioversion for atrial fibrillation.

Electrical cardioversion (ECV) is a technique used to restore sinus rhythm in atrial fibrillation (AF), aiming to reduce AF-related symptoms. Various recurrence predictors, such as non-paroxysmal pattern, prolonged duration, chronic obstructive pulmonary disease, advanced age, or left atrial dilation, have been identified. Hence, the aim of our study was to determine the parameters that could predict AF recurrence in the long term in patients who underwent ECV. One hundred seventy-two patients who underwent electrical cardioversion due to AF at our tertiary center were included in the study. Patients with recurrent AF after cardioversion were defined as the AF recurrence (+) group, and those with normal sinus rhythm were defined as the AF recurrence (-) group. Parameters that would predict AF recurrence were investigated between these two groups. AF recurrence was observed in 91 patients, while 81 patients did not experience any recurrence. The prediction model, constructed using multivariate Cox regression analysis, included six variables: non- high-density lipoprotein (HDL) cholesterol, free T3, mean corpuscular volume (MCV), left atrium anterior-posterior diameter, number of cardioversions, and oral anticoagulant use. ROC curve analysis demonstrated that our prediction model effectively distinguished between patients with arrhythmia relapse and those without, with an AUC value of 0.719 (p < .05). This study revealed that AF recurrence after ECV can be predicted by our prediction model consisting of patient characteristics, disease factors, and various biochemical parameters. The current study demonstrated a statistically significant association between the number of cardioversions and non-HDL cholesterol levels in patients with recurrent AF.

Graves’ disease in Children: A Case Report of Rare Occurrence

Graves’ disease (GD) is an autoimmune disorder that manifests as goiter, weight loss, heat intolerance, and palpitations. It is rare in preschool-aged children (&lt;5 years) and can lead to serious acute and long-term complications, including growth and development, if left undiagnosed. We present the case of a four-year-old Hindu Asian girl from a low socioeconomic background who presented with progressive thyroid enlargement and symptoms of excessive sweating, heat intolerance, weight loss, diarrhea, fatigue, and palpitations over six months. Examination revealed symmetrical goiter, signs of thyrotoxicosis, bilateral exophthalmos, and raised blood pressure. Laboratory investigations confirmed Graves’ disease with suppressed TSH, elevated T3 and free T4, and persistently high TSH receptor antibodies (TRAb &gt;40 IU/L). She was started on carbimazole and propranolol, resulting in clinical improvement; however, biochemical parameters, including TRAb levels, remain persistently elevated at eight months and suppressed TSH at 13 months, indicating a high risk of relapse. Long-term ATD therapy will be continued, with definitive treatment (RAI or thyroidectomy) considered if remission is not achieved after three years. This case underscores the challenges of managing Graves’ disease in young children and the need for prolonged monitoring and individualized treatment strategies. doi: https://doi.org/10.12669/pjms.41.4.10689 How to cite this: Butt AT, Ayaz Ur Rehman, Ramzan S, Arif M. Graves’ disease in Children: A Case Report of Rare Occurrence. Pak J Med Sci. 2025;41(4):1253-1256. doi: https://doi.org/10.12669/pjms.41.4.10689 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The Relationship Between Inflammatory Parameters in Hemogram and Thyroid Stimulating Immunoglobulin (TSI) Levels at the Beginning and the 6th Month of Treatment in Graves' Disease

Abstract Objective: Thyroid stimulating immunoglobulin (TSI) is used in the differential diagnosis of thyrotoxicosis and disease recurrence and activity. However, the accessibility and the cost can limit the use of TSI. In our study, we investigated the existence of easily accessible markers that can be used instead of TSI in the diagnosis and follow-up of Graves' disease (GD). The aim was to evaluate the relationship between TSI levels and inflammatory markers such as neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), platelet-lymphocyte ratio (TLR), systemic immune inflammation (SII) index, pan-immune inflammation value (PIV) obtained from the complete blood count of the patients at the beginning and 6 months after anti-thyroid treatment. Materials and Methods: 162 patients diagnosed with Graves' disease were retrospectively investigated. According to the free T4 level, the patients were divided into 3 groups as mild, moderate, and severe disease. Thyroid function tests, hemogram parameters, and TSI values of the patients at the time of diagnosis and after 6 months of anti-thyroid treatment were compared. The correlation of the statistically significant parameters with TSI was studied separately for each group. Results: While there was a significant increase in hemoglobin (p=0.009), leukocyte (p=0.001), neutrophil (p=0.002), lymphocyte (p=0.002), eosinophil (p=0.033), basophil (p=0.001) and TSH (p=0.001) levels after treatment compared to the baseline, there was a significant decrease in monocyte (p=0.003), platelet (p=0.010), TLR (p=0.001), MLR (p=0.001), freeT3 (p=0.001), freeT4 (p=0.001) levels. The correlation of these statistically significant parameters with TSI was observed. When the baseline and 6th month post-treatment values were investigated in all patients; a weak positive correlation was detected between TSI and monocytes and MLR, and a weak positive correlation was detected with freeT3. A weak positive correlation was detected between TSI and RDW and freeT3 in the severe disease group. Conclusion: Although a reliable marker that can be used as an alternative to TSI in the follow-up of Graves' disease has not been available, monocyte level, MLR and RDW in patients with severe Graves’ disease may predict an activation in the follow-up of the disease.

Comparison of three blood collection tubes for 16 biochemical analytes and stability assessment of selected analytes: VACUETTE® CAT serum Sep clot activator tube, VACUETTE® LH lithium heparin Sep tube, and VACUETTE® CAT serum fast separator tube.

BackgroundAnalytical performance of VACUETTE® CAT Serum Fast Separator Tube (SFT; Greiner Bio-One, Austria), recently developed quick-clotting serum separator, was evaluated for correlation and stability, comparing with VACUETTE® CAT Serum Sep Clot Activator Tube (SST; Greiner Bio-One) and VACUETTE® LH Lithium Heparin Sep Tube (LiHep Tube; Greiner Bio-One).MethodFor 107 paired samples, 16 analytes (glucose, potassium, LDH, CRP, creatinine, AST, ALT, ALP, GGT, AFP, PSA, TSH, free T4, iPTH, CK-MB, and cardiac troponin I[cTnI]) were measured. Correlations were assessed using Passing-Bablok regression and paired t-tests. Differences were evaluated by comparing the mean percentage difference and estimated difference at medical decision limits (MDLs), to the acceptable desirable difference. For six analytes - glucose, potassium, LDH, AST, iPTH, and cTnI - known for different stabilities between sample types, stability was evaluated by comparing changes over time with desirable differences.ResultsAcross the evaluated range, SFT showed clinically comparable differences to SST, except for CK-MB which showed significant positive bias. Plasma exhibited unacceptable biases: negative for potassium and positive for LDH and CK-MB. Estimated differences at MDLs were acceptable in SFT except for potassium and CK-MB, while plasma showed unacceptable differences in potassium, LDH, creatinine, and CK-MB. LiHep Tube showed reduced stability than SST for all analytes except for iPTH, impairing retest reliability. SFT showed comparable stability except for LDH and iPTH, which showed slightly shortened stability.ConclusionsThe SFT demonstrated high correlation and comparable stability to SST, making it a suitable replacement for the LiHep Tube, as an alternative to SST for rapid testing.

Focus on the endocrine system of children born after reproductive technologies in Kazakhstan

Introduction: Reproductive technologies are used more widely today than ever before. This increase in the use of assisted reproductive technology (ART) is directly related to sociodemographic conditions that result in delayed childbirth among age groups with lower fertility. Infertility affects 17% of married couples, and in some countries 6% of children are born with in vitro fertilization (IVF). In this context, the aspect of the influence of reproductive technologies on hormonal indicators of offspring in relation to anthropometric data remains insufficiently examined. The purpose of this cohort study is to compare the hormonal panel and anthropometric data of ART-conceived children with the corresponding data of children conceived naturally. Methodology: Biochemical tests are used to determine the amount of free triiodothyronine (T3) and total thyroxine (T4), somatotropin, insulin, insulin-like growth factor, glucose, potassium, and sodium cations in blood samples from the experimental and control groups. Results: The results indicate that the use of assisted reproductive technologies neither altered the endocrine panel of the thyroid gland, nor affected other biochemical parameters. Variations in technologies – classical IVF, fresh or frozen embryo transfer, intracytoplasmic sperm injection – also did not affect the quantitative value of the above indicators. Artificial insemination also had no effect on puberty (in both boys and girls). Children born naturally had a greater body weight (3,453 vs 3,160 g, p &lt; 0.001) and height (53 vs 51 cm, p = 0.002). ART children had significantly higher median free T3 levels (3.65 vs 3.48 mU/L, p = 0.002) and potassium levels (4.8 vs 4.7 mmol/L, p = 0.013), although within the reference ranges. Glucose levels were also higher in ART children (median 4.45 vs 4.29 mg/dl, p = 0.01). Conclusion: Several relationships between biochemical and anthropometric indicators were identified: the correlation between body weight and blood levels of insulin-like growth factor was statistically significant, positive, and weak. The T3 level in the experimental group was found to be statistically significant and directly proportional to body height, and insulin content was inversely proportional to body weight. The data obtained make it possible to verify the safety of using a different range of reproductive technologies.

The Association Between Per- and Polyfluoroalkyl Substances Exposure and Thyroid Hormones in Men and Non-Pregnant Women: A Systematic Review and Meta-Analysis.

Studies have shown that per- and polyfluoroalkyl substances (PFAS) may impact thyroid function in human health. While the consistency between PFAS exposure and thyroid health effects in pregnant women has been validated, the effects on men and non-pregnant women remains inconclusive. To address this, a meta-analysis was carried out in this paper, with 14 eligible studies retrieved from Embase, PubMed, and Web of Science that were published up to 2 June 2024, focusing on the relationship between PFAS exposure and its effect on thyroid hormone levels in the human body. The thyroid function indexes analyzed included thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), free T3 (FT3), and free T4 (FT4). The estimated value (β) and the corresponding confidence interval (95% CI) were extracted from the literature. A heterogeneity test was carried out, and the sensitivity analysis and publication bias of the studies were analyzed using Stata 18.0. The results revealed that in men and non-pregnant women, PFOA was positively correlated with FT3 (β = 0.011, 95% CI = 0.001, 0.02, I2 = 13.4). However, no significant associations were found between exposure to other PFAS and thyroid hormones. A subgroup analysis further indicated that the correlations between PFAS exposure and thyroid hormone levels were more significant in adolescents, in both America and Europe.

The impact of thyroid function on surgical prognosis in patients undergoing cardiac and major vascular surgeries

ObjectiveThis study aims to elucidate the relationship between thyroid function and surgical prognosis in patients undergoing cardiac and major vascular surgeries.MethodsA retrospective cohort study was conducted on patients undergoing cardiac or major vascular surgeries. Preoperative thyroid function tests, including TSH, free T3, and free T4 levels, as well as postoperative thyroid function tests, were assessed. Key postoperative outcomes, such as total hospital stay, postoperative hospital stay, ICU stay, and duration of mechanical ventilation, were recorded and analyzed. The analytical approach included Pearson correlation, multivariable logistic regression models, and restricted cubic splines.ResultsThis study analyzed a cohort of 472 patients who underwent various cardiovascular surgeries, including coronary artery bypass grafting (173 patients), aortic surgery (131 patients), valve surgery (125 patients), and primary cardiac neoplasms resection (43 patients). Significant changes in thyroid hormone levels were observed preoperatively and postoperatively, with TSH, FT3, and FT4 levels showing a significant decrease from preoperative values (p < 0.001). Multivariate logistic regression analysis further revealed that ΔTSH is significantly associated with total hospital stay, postoperative hospital stay, and duration of mechanical ventilation; postoperative FT3 levels were significantly inversely related to total hospital stay, ICU stay, and ventilator requirements. Additionally, although no significant nonlinear relationships were found (all p > 0.05).ConclusionsThyroid dysfunction may impact postoperative outcomes in cardiac and major vascular surgery patients.

Prevalence of Gestational Auto-immune Thyroid Dysfunction and its Association with Anaemia In A Rural District Of West Bengal

Background: Maternal thyroid dysfunction is associated with risk of obstetric complications and also heralding the risk of abnormal fetal neuro-development. The prevalence and type of thyroid dysfunction in pregnancy varies widely according to ethnicity, demographic and geographical location. Thyroid dysfunction in pregnancy may be associated with autoimmune component too. Anaemia in pregnancy may aggravate with thyroid dysfunction in comparison to euthyroid pregnant subjects. Some epidemiological studies suggested that Iron deficiency anemia may be related to autoimmune thyroid dysfunction in pregnancy. This study aimed to estimate the prevalence of thyroid dysfunction in different trimesters of pregnancy, the association with anemia in pregnancy and whether autoimmunity plays a role in development of thyroid disorder. Methodology: A cross-sectional study was conducted over a period of 1 year in the department of Biochemistry of Bankura Sammilani Medical College. Antenatal mothers attending the antenatal OPD in different trimester were selected depending on predefined inclusion and exclusion criteria. Blood samples were collected for estimation of serum TSH, Free T4, haemoglobin, haematocrit, RBC indices. Serum anti-TPO antibody was estimated only in patients with altered thyroid hormone concentration. Results of the study was compiled, tabulated and analysed using SPSS version 21. Results: 326 pregnant mothers were included as study participants among which 164 were in first trimester and 162 were in second trimester.The prevalence of hypothyroidism among pregnant women was found to be 46.3 % whereas only 1.8% were hyperthyroid.93.3% of the hypothyroid pregnant women had sub-clinical hypothyroidism and the remaining had overt hypothyroidism. 8 subjects out of the total 157 patients with deranged thyroid function were found to be anti-TPO positive. The prevalence of iron deficiency anaemia among hypothyroid mothers were 36.4% in comparison to 33.1 % in non-hypothyroid mothers. Conclusion: Screening of thyroid function status in various stages of gestation is essential because of the high prevalence of hypothyroidism among pregnant women. Estimation of serum anti TPO antibody should be done in all thyroid dysfunctions. Thyroid disorders in pregnancy may be associated with increased severity of iron deficiency anaemia.

A feasibility double-blind trial of levothyroxine vs. levothyroxine-liothyronine in postsurgical hypothyroidism.

Despite normalization of Thyrotropin (TSH), some patients with hypothyroidism treated with Levothyroxine (LT4) report residual symptoms which may be attributable to loss of endogenous triiodothyronine (T3). Feasibility trial LT4/liothyronine (LT3) combination vs. LT4/placebo in post-surgical hypothyroidism. Double-blind, placebo-controlled, 24-week study. Academic medical center. Individuals with indications for total thyroidectomy and replacement therapy. LT4/LT3 5 mcg (twice daily) vs. LT4/placebo (twice daily). LT4 was adjusted at 6- and 12-weeks with the goal of baseline TSH ± 0.5 mcIU/ml. Changes in body weight, cholesterol, TSH, total T3, free tetraiodothyronine (T4). Cardiovascular function, energy expenditure, and quality of life (ThyPRO-39) were assessed in patients who completed at least the 3-month visit, last measure carried-forward. Twelve patients (10 women and 2 men), age 51 ± 13.8 years (7 LT4/placebo, 5 LT4/LT3), were analyzed. No significant differences were observed in TSH. Following thyroidectomy, LT4/placebo resulted in higher free T4 + 0.26 ± 0.15 p<0.005 and lower total T3 -18 ± 9.6 ng/dl p<0.003, respectively, not observed in the LT4/LT3 group. The LT4/placebo group had a non-significant increase in body weight, +1.7 ± 3.8 Kg, total- and LDL-cholesterol +43.1 ± 72.8 and +32.0 ± 64.4 mg/dl. Conversely the LT4/LT3 group changes were -0.6 ± 1.9 Kg, -28.8 ± 49.0 and -19.0 ± 28.3 mg/dl, respectively, all non-significant. Non-significant improvement were observed in ThyPRO-39 measures in both groups, while energy expenditure, and diastolic function increased in the LT4/LT3 group. In this group of patients with post-surgical hypothyroidism LT4 replacement alone does not normalize free T4 and total T3 levels and is associated with non-significant increase in weight and cholesterol. LT4/LT3 combination therapy appears to prevent these changes. Clinicatrials.gov, identifier NCT05682482.

Oral nicotinic acid administration effect on lipids, thyroid hormones, and oxidative stress in intact adult dogs

BackgroundNicotinic acid (niacin, Vitamin B3) is one of the most effective medicines for improving high-density lipoprotein concentrations. Obesity and related diseases are life-threatening to dogs. This study investigated the niacin effect on triglyceride, cholesterol, lipoproteins, thyroid hormones, oxidative stress, and lipid peroxidation in intact adult dogs. Blood samples were taken from seven healthy, intact adult dogs as a control group (day 0). Then, the animals received 1000 mg/dog of oral nicotinic acid tab daily for 42 days, and blood sampling was performed on days 14, 28, 42, and 56.ResultThe results showed an increasing trend in high-density lipoprotein (HDL) concentration. The highest HDL concentration (138.85 ± 43.72 mg/dl) was related to day 56; the HDL level followed a statistically significant increase between day 14 and 56. Unlike HDL, there was a decreasing trend in low-density lipoprotein (LDL) concentration. The lowest LDL concentration (21.85 ± 18.60 mg/dl) was related to day 56. The concentration of apolipoprotein A-I (apoA1) was significantly increased during the study. The highest concentration of apoA1 (1.66 ± 0.06 g/l) was on day 42. There was a significant increase in apoA1 concentrations between days 0 and 14, 42, and 56. The apoA1 was significantly increased between days 14 and 42 and 56. The apoA1 followed a statistically significant increase between days 28 and 42. Changes in thyroid hormone levels did not show any constant increasing or decreasing trend. On day 14, a decreasing trend in the concentrations of TT4, FT4, and T3 was observed. However, an increasing trend was detected in the concentrations of TT4, FT4, and T3 on days 28 and 42. However, the increase in the concentrations of TT4 and FT4 was less than that on day 0. After treatment (day 56), a decreasing trend was observed in thyroid hormone concentrations. The negative correlation was detected between apoA1 and triiodothyronine (T3), total thyroxine T4 (TT4)), and free T4 (FT4) concentrations on day 42. Furthermore, a significant negative relationship was observed between HDL and T4 on day 42. However, the relationship between triglyceride and T3 was statistically positive on day 14. There was an increasing trend in serum total antioxidant capacity (TAC). The highest TAC concentration (3.83 ± 0.62 µmol /l) was on day 56; however, the malondialdehyde (MDA) concentration was decreased during the study. The total antioxidant level followed a statistically significant increase between days 0 and 56 compared to days 14 and 42.ConclusionThe study demonstrated the efficacy of nicotinic acid in improving serum HDL, apoA1, and TAC, as well as decreasing serum MDA and LDL concentrations.