Normal Thyroid-stimulating Hormone Levels Research Articles

Фактори кардіоваскулярного ризику у хворих на артеріальну гіпертензію при різному рівні тиреотропного гормону

Метою роботи було встановити вплив рівня тиреотропного гормону (ТТГ) на частоту і вираженість факторів кардіоваскулярного ризику у хворих на артеріальну гіпертензію (АГ). Були обстежені 123 хворі із АГ I–II ступенів віком 45–70 років. Методи дослідження: визначення показників ліпідограми, ТТГ, вільного тироксину, ехокардіографія, вимірювання офісного артеріального тиску (АТ), дуплексне сканування судин шиї, тестування за госпітальними шкалами тривоги і депресії. Серед обстежених хворих 12,4 % мали не діагностований раніше субклінічний гіпотиреоз, що асоціювався з більшою частотою дисліпідемії, порушення вуглеводного обміну, гіпертрофії лівого шлуночка і атеросклеротичного ураження сонних артерій, більш високими значеннями пульсового АТ, а також зі зменшенням швидкості клубочкової фільтрації і тривожно-депресивними розладами. При аналізі групи з нормальною функцією щитоподібної залози (ЩЗ) було виявлено, що високонормальний рівень ТТГ (2–4 мОд/л) також пов’язаний зі збільшенням частоти факторів кардіоваскулярного ризику і погіршенням стану органів-мішеней порівняно з особами із низьконормальним рівнем ТТГ. Отже, функціональний стан ЩЗ впливає на частоту та вираженість факторів ризику і уражень органів-мішеней при АГ, що потребує ретельного його контролю у хворих із кардіологічною патологією.

More Live Births in Primary Subfertile Intracytoplasmic Sperm Injection-Treated Women with High Normal TSH Levels

Objectives: The aim of this study was to analyze the fertility outcome in intracytoplasmic sperm injection (ICSI)-treated women across normal range thyroid-stimulating hormone (TSH) levels. Published results are inconclusive about optimal TSH levels and fertility. Design: This is a retrospective cohort study in 752 ICSI-treated women with predominantly severe male factor subfertility, starting treatment between the first of January 2008 and the first of March 2012 with a follow-up until 2014. Participants/Materials, Setting, Methods: Women aged 22–45 years with TSH 0.3–4.5 mIU/L without thyroid hormone substitution were included in Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands, an iodine-sufficient area. Demographic and baseline characteristics were compared between groups of patients based on TSH, using one-way ANOVA, Kruskal-Wallis ANOVA, and χ² test. The patient was the unit of analysis: all cumulative cycles per patient were analyzed up to and including the first ongoing pregnancy. The primary outcome was a cumulative live birth rate. Clinical pregnancy rate, pregnancy loss, and ongoing pregnancy rate were secondary outcomes. The χ² test and logistic regression were used to compare interquartile groups while adjusting for confounders. Logistic regression was used with the natural logarithm of TSH as a continuous predictor. Primary and secondary subfertile women were analyzed separately. Results: Analysis of the total cohort (n = 752) showed no difference in fertility outcomes across the normal TSH range. The cumulative live birth rate for the 4 groups of primary subfertile women (n = 455) was 76% in the upper TSH quartile compared to 56%, 60%, and 59% in the lower TSH quartiles. Limitations: Levels of thyroxine and presence of thyroid autoimmunity were not measured in this retrospective cohort study. Conclusions: The observation that a higher live birth rate was found in primary subfertile ICSI-treated women with high but allegedly normal TSH levels contributes to the hypothesis that in certain subfertile women in addition to a male factor, female factors such as subtle hypothyroidism and/or thyroid autoimmunity may play a role in keeping them from conception, which can be overcome by the process of ICSI.

Elevated thyroid-stimulating hormone levels are associated with poor sleep: a cross-sectional and longitudinal study.

Poor sleep accompanied by elevated TSH (thyroid stimulating hormone) levels is not uncommon since TSH secretion is controlled by the circadian rhythm. However, the relationship between poor sleep and TSH elevation is unclear; hence, we aimed to elucidate this relationship by conducting a cross-sectional and longitudinal study. Participants with isolated elevated (N = 168) and normal (N = 119) TSH concentrations were recruited, and the Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep status. Subjects with an isolated TSH elevation were followed up longitudinally. The serum TSH concentration was remeasured after sleep status improved. The proportions of poor sleep and occasional poor sleep in subjects with isolated TSH elevation were significantly higher than those with normal TSH levels (70.24% vs. 49.58%, p = 0.001; 9.52% vs. 1.68%, p = 0.006). Subjects with isolated TSH elevation had significantly higher PSQI scores in the subjective sleep quality, sleep latency, sleep duration, and habitual sleep efficiency dimensions than those with normal TSH levels (all p < 0.05). Poor sleep was significantly associated with isolated TSH elevation in the multiple logistic regression analysis [odds ratio (OR) = 2.396, p = 0.001]. Among subjects with an isolated TSH elevation at baseline, the percentage of TSH normalization was significantly higher in those who slept better than in those who still slept poorly (85.42% vs. 6.45%, p < 0.001). This study revealed that isolated elevated TSH concentrations normalize when the sleep status is improved; hence, we recommend that clinicians thoroughly assess the sleep status of patients and remeasure TSH concentrations after sleep status improves.

The factors associated with transient hypothyroxinemia of prematurity

BackgroundHypothyroxinemia is defined by low levels of thyroxine (T4) despite low or normal levels of thyroid-stimulating hormone (TSH). This study aimed to evaluate the factors associated with transient hypothyroxinemia of prematurity (THOP) in newborns admitted to the neonatal intensive care unit (NICU).MethodThis is a single center, retrospective, case-control study. Premature newborns, between 24 and 34 weeks of gestation, hospitalised between January 2014–December 2019 in Istanbul University-Cerrahpasa Faculty of Medicine NICU were analyzed through their medical records. Thyroid function tests were routinely performed between the 10th and 20th days of postnatal life and were evaluated according to the gestational age references. Thirty six possible associated factors (prenatal and postnatal parameters, medical treatments, clinical diagnoses and applications in NICU) were searched in the patient group with THOP (n = 71) and the control group with euthyroid prematures (n = 73). The factors for THOP were identified by univariate analysis, followed by multivariate analysis.ResultsMean gestational ages of the study and the control groups were 29.7 ± 2.48 and 30.5 ± 2.30 weeks, respectively (p = 0.606). The birth weight, small for gestational age (SGA), intraventricular hemorrhage (IVH), congenital heart disease (CHD) were found to be the possible associated factors for THOP in the univariate analysis and CHD (p = 0.007, odds ratio [OR]:4.9, 95% confidence interval [CI]: 1.5–15.8), BW (p = 0.004, OR:0.999, 95% CI: 0.9–1.0) and SGA (p = 0.010, OR:4.6, 95% CI: 1.4–14.7) were found to be factors associated with THOP determined by univariate logistic regression analysis.ConclusıonsAlthough some treatment practices might have had direct effects on pituitary–thyroid axis, related with the severity of the newborn clinical conditions, non of them was found to be a associated factor for THOP. However, CHD and SGA may be considered as associated factors with THOP detected in preterm infants.

MEANS TO OPTIMIZE THE TREATMENT OF DYSLIPIDEMIA IN PATIENTS WITH HYPOTHYROIDISM

In order to study the peculiarities of lipid metabolism and atorvastatin efficacy for patients with hypothyroidism, it was examined 133 patients with manifested hypothyroidism. It was revealed malfunction lipid metabolism, i. e. a direct correlation between total cholesterol levels and thyroidstimulating hormone (TSH). It was confirmed, that higher indices of dyslipidemia are associated with the most manifested abdominal obesity and with higher body mass index. Reaching of normal levels of thyroid-stimulating hormone during hormone-replacing therapy is not sufficient to gain the required levels of major indices in lipid profile. It was proved efficacy of atorvastatin in complex treatment of hypothyroidism.

26966 Tofacitinib treats unresponsive vitiligo and elevated thyroid peroxidase antibodies

A 56-year-old female presented with expanding vitiligo to 35% total body surface area (TBSA) despite treatment with alpha lipoic acid, vitamin C, vitamin E, polypodium leucotomus, topical pimecrolimus, narrowband ultraviolet B, and excimer laser for 2 months. Past medical history was pertinent for Hashimoto thyroiditis treated with levothyroxine with normal levels of thyroid stimulating hormone (TSH) and free thyroxine (FT4), psoriatic arthritis, alopecia, and localized psoriasis on the elbows. Notably, lab tests confirmed normal levels of serum TSH and FT4 but elevated thyroid peroxidase antibodies (TPO) of 795 and elevated thyroglobulin antibodies (TG) of 3. Her endocrinologist denied necessity of treating patients for elevated TPO but stated that patients were only treated with increased dosages of levothyroxine. Because of reported case reports of success in treating vitiligo and FDA-approval for psoriatic arthritis, tofacitinib 5 mg (Tofa) twice daily (BID) was added to the treatment regimen. Serum levels of TPO and TG normalized within 1 month, with simultaneous improvement in vitiligo. Because of gastrointestinal side effects after BID dosing for 5 months, Tofa was decreased to once daily, with continued vitiligo repigmentation. By then, vitiligo had decreased to 12% TBSA, with accompanying improvement in alopecia, psoriatic arthritis, and psoriasis. This case suggests that unstable vitiligo may be associated with elevated TPO and TG, because of a disregard of endocrinologists to treat elevated antibodies, and should be tested in patients with unresponsive vitiligo. Tofacitinib may ameliorate vitiligo not only as a Janus kinase inhibitor but also through an effect on TPO and TG.

Overtreatment of Transient Maternal Hyperthyroidism Resulting in Fetal Goiter.

Overtreatment of Transient Maternal Hyperthyroidism Resulting in Fetal Goiter.

Appropriate dose of levothyroxine replacement therapy for hypothyroid obese patients

BackgroundAthyreotic patients require a daily levothyroxine (LT4) doses of 1.6–1.8 mcg/kg of actual body weight (BW) to achieve normal thyroid stimulating hormone (TSH) levels. Lean body mass (LBM) calculation may be a more accurate determination of LT4 dose in obese patients. Previous studies were mainly investigated in Caucasians and LBM is markedly different between various ethnic groups. We aim to identify the optimal dose of LT4 replacement therapy in hypothyroid Thai patients including obese subjects. MethodsWe retrospectively reviewed the medical records of Thai adults with hypothyroidism at the thyroid clinic. Patients had been received LT4 (Brand: Euthyrox) at a stable dose ≥ 75 mcg/day for at least 1 year. Patients with thyroid cancer, pregnant, and lactating women were excluded. LBM was calculated by the Hume formula. ResultsTwo hundred patients (80% females) with a mean age of 48.6 ± 14.8 years and a body mass index (BMI) of 24.5 ± 4.6 kg/m2 were included. Daily LT4 dose/kg of actual BW according to BMI 18.5–24.9, 25–29.9, and ≥ 30 kg/m2 were 1.67 ± 0.27, 1.51 ± 0.28 and 1.39 ± 0.34 mcg/kg, respectively. In contrast, LT4 dose/kg of LBM were 2.31 ± 0.39, 2.35 ± 0.45 and 2.36 ± 0.51 mcg/kg, respectively. ConclusionsLBM is considered a better indicator for calculating an appropriate LT4 replacement dose than actual BW in hypothyroid obese Thai patients. The recommended daily dose of LT4 is 2.3 mcg/kg of LBM that could be applied for all ranges of BMI.

English

BACKGROUND The importance of adequate iodine status in pregnancy is undoubted as its deficiency is associated with adverse pregnancy outcomes for the mother as well as the foetus and neonate. Although median urine iodine concentration can assess iodine status of the population but not at an individual level. The purpose of this study was to assess the nutritional status of iodine and identify its effects on thyroid function during the first trimester of pregnancy. METHODS The study was carried out on 341 euthyroid healthy pregnant women using urine iodine concentration and other parameters of thyroid panel at a tertiary care hospital. RESULTS Median (interquartile range) urine iodine concentration and thyroid stimulating hormone (TSH) were 227.37 (161.7, 343.86) μg / L and 1.8 (1.1, 2.7) mIU / L respectively and Mean ± SD of free thyroxine and thyroid peroxidase antibodies were 14.53 ± 2.02 pmol / L and 38.23 ± 9.29 kIU / L respectively. Only thyroid peroxidase antibodies showed significant difference across groups with different iodine status. A positive correlation of urine iodine concentration (UIC) with thyroid peroxidase antibodies was observed (r = 0.137, P = 0.011). Multiple regression analysis revealed that thyroid peroxidase antibodies can serve as an independent predictor of iodine status in the presence of normal levels of TSH and FT4 (t - 3.063, CI; 0.880, 4.038, P = 0.002). CONCLUSIONS Thyroid peroxidase antibodies progressed positively with increase in urine iodine concentration indicating its role as a marker of iodine nutritional status and for early identification of women who can develop autoimmune thyroiditis resulting in hypothyroidism even prior to elevation of thyroid stimulating hormone levels. KEY WORDS Anti-TPO Ab, Free Thyroxine, Thyroid Stimulating Hormone, Urine Iodine Concentration

A Galvanizing Solution: Colonoscopy Bowel Preparation as a Trigger for Supraventricular Tachycardia.

Polyethylene glycol (PEG)-based solutions are among the most commonly used bowel preparation regimens for colonoscopy. Although these solutions are well tolerated, rare adverse cardiac events have been reported. We sought to identify the characteristics that may predispose patients to develop supraventricular tachycardia (SVT) after ingestion of GoLYTELY (PEG 3350 and electrolytes oral solution) in anticipation for their colonoscopy. We performed a retrospective observational cohort study of the electronic medical record of all patients who developed SVT after ingestion of GoLYTELY solution from April 2012 to March 2019 at the John D. Dingell VA Medical Center. Clinical data were obtained through review of medical records. We identified 16 patients with new-onset SVT after ingestion of bowel preparation solution before undergoing the colonoscopy procedure. In all, 12 (75%) patients developed atrial fibrillation, 3 (18.8%) patients developed atrial tachycardia, and 1 patient (6.3%) developed atrial flutter. Most patients were male (93.8%), and the mean age was 69 ± 8.2 years. The commonly associated comorbidities were hypertension (87.5%), hyperlipidemia (56.3%), and diabetes (37.5%). Laboratory testing demonstrated a normal electrolyte panel and thyroid stimulating hormone level. A significant percentage of patients had dilated atria and left-ventricular hypertrophy on echocardiogram. Our case series suggests that there may be certain individuals who are predisposed to development of atrial arrhythmias, more so than others, after ingestion of PEG based solution for colonoscopy. We hypothesize that the combination of atrial dilation, sympathovagal discharge, and transient electrolyte shifts at the cellular level led to the development of SVTs.

PND53 Predictive Models Leveraging Machine Learning and Real-World Data for Early Diagnosis: An Application in Amyotrophic Lateral Sclerosis

To assess the utility of machine learning for predicting early diagnosis of amyotrophic lateral sclerosis (ALS) based on real-world data (RWD). We identified 4779 patients with ALS and without primary lateral sclerosis from the Optum® de-identified Electronic Health Record (EHR) dataset (2007-2020), and 47,781 patients as the control cohort who did not have ALS and were demographically matched by age and gender in a 1:10 target to control ratio. Mutual information was used to explore and identify features in RWD, including lab, microbiology, and natural language processing biomarkers available in EHR, by comparing the target population (ALS patients) with the demographically matched control cohort. We trained various machine learning models (eg, logistic regression, random forest, gradient boosting, support vector machines, neural networks, soft voting) spanning different periods of time relative to a defined index date and compared their performance in predicting early diagnosis of ALS. Predictive models trained with gradient boosting on data closer to the defined index date, including lab tests from EHR, performed the best and had a very low false positive rate (AUC=0.9463). This model suggested that the top 5 predictors of an undiagnosed ALS patient were muscle weakness (generalized), normal thyroid stimulating hormone levels, dysphagia (unspecified), cramp of limb/abnormal involuntary movements, and other musculoskeletal symptoms referable to limbs. Many of the features were diagnoses that could be considered for an earlier evaluation of ALS in clinical practice. Indeed, the model had a sensitivity of 1%, specificity >99.0%, and was able to identify with a precision of 63% patients not yet identified with ALS, suggesting that early screening for ALS would be beneficial. This study highlights opportunities of leveraging machine learning utilizing EHR RWD to identify features that predict early diagnosis of ALS.

Prognostic significance of low TSH concentration in patients with COVID-19 presenting with non-thyroidal illness syndrome

BackgroundLow free triiodothyronine (FT3) levels are related to a poor prognosis deterioration in patients with COVID-19 presenting with non-thyroidal illness syndrome (NTI). This study was designed to explore whether free thyroxin (FT4) or thyroid stimulating hormone (TSH) levels affected the mortality of patients with COVID-19 presenting with NTI.MethodsPatients with COVID-19 complicated with NTI who were treated at our hospital were included in this retrospective study. Patients were divided into low TSH and normal TSH groups, as well as low and normal-high FT4 group, according to the reference range of TSH or FT4 levels. The 90-day mortality and critical illness rates were compared among patients with low and normal TSH levels, as well as among patients with low FT4 levels and normal-high FT4 levels; in addition, differences in demographic and laboratory data were compared. A Kaplan-Meier analysis and Cox proportional hazards models were used to assess the associations of TSH and FT4 levels with mortality.ResultsOne hundred fifty patients with low FT3 levels and without a history of thyroid disease were included, 68% of whom had normal FT4 and TSH levels. Critical illness rates (74.07% VS 37.40%, P = 0.001) and mortality rates (51.85% VS 22.76%, P = 0.002) were significantly higher in the low TSH group than in the normal TSH group. Although no significant difference in the critical illness rate was found (P = 0.296), the mortality rate was significantly higher in the low FT4 group (P = 0.038). Low TSH levels were independently related to 90-day mortality (hazard ratio = 2.78, 95% CI:1.42–5.552, P = 0.003).ConclusionsLow FT4 and TSH concentrations were associated with mortality in patients with COVID-19 presenting with NTI; moreover, low TSH levels were an independent risk factor for mortality in these patients.

Serum lipids are novel predictors for thyroid autoimmunity in the general population with normal TSH levels from a cross-sectional study.

Serum lipids have been shown to regulate inflammatory and immune processes, but little is known about their association with thyroid autoimmunity. This study aimed to investigate the association of serum lipids with thyroid autoantibody positivity in the general population with normal thyroid-stimulating hormone (TSH) levels. Data regarding the 7688 subjects' baseline characteristics were retrospectively collected. All subjects were categorized into four groups according to thyroid autoantibodies against thyroglobulin (TgAb) and thyroid peroxidase (TPOAb) positivity and serum lipid levels were compared. Binary logistic regression models were used to evaluate the risk of TgAb or TPOAb positivity with increasing serum lipid levels. In 6456 included subjects, after adjusting for confounders, the risk of TgAb positivity was positively associated with increasing low-density lipoprotein cholesterol (LDL-C) levels (OR 1.14, 95% CI 1.03-1.27, P = 0.011) and negatively correlated with the increasing high-density lipoprotein cholesterol (HDL-C) levels (OR 0.77, 95% CI 0.61-0.98, P = 0.035). In female subjects, the association between increasing LDL-C (OR 1.16, 95% CI 1.04-1.28, P = 0.007) or HDL-C levels (OR 0.77, 95% CI 0.61-0.99, P = 0.037) and TgAb positivity become more pronounced. We have shown the associations of HDL-C and LDL-C with TgAb positivity in the general population with normal TSH levels in a gender-dependent manner. This study highlights that serum lipids may be new predictors of thyroid autoimmunity even when TSH is within the reference range.

Growth Hormone (GH) and Thyroid Stimulating Hormone (TSH) Co-Secreting Pituitary Macroadenoma

Background: TSH secreting pituitary adenomas are rare and accounts for 0.5-3% of all pituitary adenomas. Only 20-25% of those adenomas co-secrete other hormones like growth hormone or prolactin. Mixed GH and TSH secreting adenomas present with symptoms from tumor growth and features of both acromegaly and hyperthyroidism. Clinical Case: A 57 years old woman with a past medical history of chronic joint pains and bilateral knee swelling presented to her PCP with complaints of chronic fatigue. Evaluation revealed a normal TSH level and MNG and patient did not have any further work-up. She reported undergoing periodic knee arthrocentesis which gave her only temporary pain relief. Two years later, patient presented with complaints of unintentional weight loss, tremors and palpitations. She also reported enlargement in the size of hands, feet and forehead and no improvement in the knee swelling after multiple arthrocentesis. Lab evaluation revealed high free T4 2.31ng/dl (0.58-1.64), high free T3 6.44pg/ml (2.50-4.30), non-suppressed TSH 1.32mU/L (0.34-5.00), elevated IGF-1 415ng/ml (47-236), GH 7.76ng/ml (0.01-3.61) and prolactin 6.69ng/mL (2.74-26.72). Neck USG showed multiple nodules and 24hr radioactive iodine uptake scan showed increased uptake at 43%. 75gm OGTT showed non-suppression of GH level. MRI of brain showed 1.8 cm pituitary macroadenoma. Patient underwent transsphenoidal pituitary resection in January 2018 and the final pathology showed positive tumor staining for GH and TSH. Following surgery, patient reported improvement in symptoms. Lab work-up from October 2018 showed normal IGF 189 ng/ml (47-236), normal GH 0.35(0.01-3.61), Free T4 0.80(0.58-1.64), Free T3 2.41(2.50-4.30), TSH 0.06(0.34-5.00) and MRI from August 2020 showed no evidence of residual pituitary tumor. Conclusion: This is a rare case of a GH and TSH co-secreting pituitary macroadenoma. This case highlights the importance of considering acromegaly early in the differential diagnosis of patients presenting with chronic musculoskeletal symptoms and to pursue work up for central hyperthyroidism in a hyperthyroid patient presenting with a non-suppressed TSH level.

Postnatal Serum Total Thyroxine of Very Preterm Infants and Long-Term Neurodevelopmental Outcome.

Primary congenital hypothyroidism is a disease associated with low serum thyroxine and elevated thyroid-stimulating hormone (TSH) levels. The processes of screening and treating congenital hypothyroidism, in order to prevent neurodevelopmental impairment (NDI) in newborns, have been well investigated. Unlike term infants, very preterm infants (VPIs) may experience low thyroxine with normal TSH levels (<10.0 μIU/mL) during long-stay hospitalization. In the current literature, thyroxine treatment has been evaluated only for TSH-elevated VPIs. However, the long-term impact of low thyroxine levels in certain VPIs with normal TSH levels deserves more research. Since July 2007, VPIs of this study unit received screenings at 1 month postnatal age (PNA) for serum TSH levels and total thyroxine (TT4), in addition to two national TSH screenings scheduled at 3–5 days PNA and at term equivalent age. This study aimed to establish the correlation between postnatal 1-month-old TT4 concentration and long-term NDI at 24 months corrected age among VPIs with serial normal TSH levels. VPIs born in August 2007–July 2016 were enrolled. Perinatal demography, hospitalization morbidities, and thyroid function profiles were analyzed, and we excluded those with congenital anomalies, brain injuries, elevated TSH levels, or a history of thyroxine treatments. In total, 334 VPIs were analyzed and 302 (90.4%) VPIs were followed-up. The postnatal TT4 concentration was not associated with NDI after multivariate adjustment (odd ratios 1.131, 95% confidence interval 0.969–1.32). To attribute the NDI of TSH-normal VPIs to a single postnatal TT4 concentration measurement may require more research.

The Stability of TSH, and Thyroid Hormones, in Patients Treated With Tablet, or Liquid Levo-Thyroxine.

Approximately, 5% of the population is affected by hypothyroidism, mainly women and persons aged more than 60 years. After the diagnosis of hypothyroidism the usual therapy is tablet levothyroxine (L-T4), with a monitoring of the thyroid-stimulating hormone (TSH) level in primary hypothyroidism every 6–8 weeks and L-T4 is adjusted as necessary to reach an euthyroid state. Once TSH is stabilized in the normal range, it is recommended to conduct annual testing in the treated subjects to warrant suitable replacement. More recently advances regarding L-T4 treatment are the introduction of new oral formulations: the liquid solution, and soft gel capsule. The soft gel capsule permits a quick dissolution in the acid gastric pH. The liquid preparation does not require an acid gastric environment. Many pharmacokinetic studies demonstrated a more rapid absorption for the liquid L-T4, or capsule, than with tablet. Many studies have shown that the liquid, or capsule, formulations can overcome the interaction with foods, drugs or malabsorptive conditions, that are able to impair the tablet L-T4 absorption. Lately studies have suggested that liquid L-T4 can permit to maintain more efficiently normal TSH levels in hypothyroid patients in the long-term follow-up, than tablet L-T4, both in patients with malabsorptive states, and in those without malabsorption. Further large, prospective, longitudinal studies are needed to evaluate the stability of TSH, in hypothyroid patients treated with different L-T4 formulations.

Hyponatremia and Encephalopathy in a 55-Year-old Woman with Syndrome of Inappropriate Antidiuretic Hormone Secretion as an Isolated Presentation of SARS-CoV-2 Infection.

Patient: Female, 55-year-oldFinal Diagnosis: COVID-19 • SIADHSymptoms: AMS • seizureMedication: —Clinical Procedure: —Specialty: Critical Care Medicine • NephrologyObjective:Unknown ethiologyBackground:During the coronavirus disease 2019 (COVID-19) pandemic of 2020, varied presentations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been reported. The present report is of a case of hyponatremia and encephalopathy due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH) as the main presentation of SARS-CoV-2 infection in a 55-year-old woman.Case Report:A 55-year-old woman with type II diabetes mellitus presented with confusion and slurring of speech, with a temperature of 38.5°C, heart rate of 120 bpm, blood pressure of 159/81 mmHg, and oxygen saturation of 98% on room air. She did not have edema on examination. Laboratory testing showed a low sodium level of 116 mEq/L (reference range, 135–145 mEq/L) with urine osmolarity of 364 mOsm/kg, urinary sodium of 69 mEq/L, urinary potassium of 15.6 mEq/L, and serum osmolarity of 251 mOsm/kg. The patient had normal serum thyroid-stimulating hormone and cortisol levels. A chest X-ray should no pulmonary infiltrates nor did a lumbar puncture reveal signs of infection. A real-time SARS-CoV-2 polymerase chain reaction assay was positive for COVID-19. Brain imaging with computed tomography was negative for acute infarct, intracranial hemorrhage, and mass effect. Based on findings from laboratory testing and physical examination, a diagnosis of SIADH was made. The patient was treated with 3% hypertonic saline, followed by salt tablets and fluid restriction, with improvement in her clinical symptoms and serum sodium level.Conclusions:The present report is of a rare but previously reported association with SARS-CoV-2 infection. Encephalopathy and hyponatremia associated with SIADH without pneumonia or other symptoms of infection should be an indication for testing for SARS-CoV-2 infection.

Normal Levels of TSH Affect the Metabolic Profile Differently in Physically Active Males and Females

Our study was aimed at the evaluation of relationships between thyroid stimulating hormone (TSH) within the normal range and metabolic risk factors (glucose, insulin, HOMA-IR and lipoprotein profile) in physically active male and female students. In 219 students circulating TSH, glucose, insulin and lipoproteins were measured in blood under fasting conditions. Insulin resistance was expressed as HOMA-IR (homeostasis model assessment for insulin resistance). For further procedures 99 males and 97 regularly menstruating females with TSH 0.4–4.0 μIU/ml were accepted. In male students no correlations between circulating TSH, anthropometric and biochemical variables were noted. In females TSH within the normal range was slightly but significantly correlated with the triglyceride (TG) level (p < 0.03). However, step-wise multiple regression analysis revealed that the effect of TSH was small (p < 0.046) in relation to that found for HOMA-IR ( p < 0.0009). No relationships between biochemical variables and normal levels of TSH were noted in male students. However, surprisingly normal range TSH in males was slightly but significantly correlated with the percentage of body fat and this issue needs further studies concerning measurements of different fat depots. The above data suggests that in active females TG synthesis and export from the liver is more sensitive to TSH action than in active male counterparts.

ISOLATED MATERNAL HYPOTHYROXINEMIA AND ITS PERINATAL OUTCOME IN NORTH MACEDONIA.

SUMMARYIsolated maternal hypothyroxinemia (IMH) is defined as the presence of low maternal total thyroxine (TT4) level in conjunction with normal maternal thyroid-stimulating hormone (TSH) level. The aim was to investigate whether IMH is associated with adverse pregnancy outcome in North Macedonia. Dried blood spot samples were obtained from 359 pregnant women meeting the inclusion criteria and analyzed for TT4 and TSH. Postpartum data were entered from their medical histories. Out of 359 women, 131 (37.42%) belonged to IMH group. There were statistically significant differences in birth weight (p=0.043), intrauterine growth restriction (IUGR) (p=0.028), Apgar score at 1 min <7 (p=0.018) and cesarean section for dystocia/disproportion (p=0.024) between the IMH and normal thyroid function (NTF) groups. In regression analysis, TSH was a significant variable predicting Apgar score (βst=0.05597, p=0.047), body mass index predicting birth weight (βst=0.02338, p=0.045) and TT4 predicting small for gestational age/IUGR (βst=-0.089834, p=0.029) in IMH group. TT4 was a strong predictor of birth weight (βst=-0.004778, p=0.003) and premature delivery (βst=0.028112, p=0.004) in NTF group. The impact of IMH in pregnancy remains controversial. IMH was associated with an increased maternal BMI and higher birth weight of neonates. Overweight could be a potential risk factor for thyroid dysfunction in pregnant women, and specifically IMH. The worst fetal outcome was seen in IMH mothers examined in second trimester. We found TSH, TT4 and BMI to be strong predictors of perinatal outcomes.

The association between serum TSH concentration whithin the normal range and nutritional status in euthyroid pregnant women at the first trimester of gestation.

Background:Follow-up studies have shown an increased risk of thyroid dysfunction in individuals with normal serum thyroid-stimulating hormone (TSH) levels. Furthermore, the possible consequences of minor differences in thyroid function (without achieving poor thyroid function) in the risk of weight gain during pregnancy are questionable, too. The production of TSH is under the hypothalamus–pituitary control, and food is one of the most effective environmental agents that control hypothalamic–pituitary–thyroid axis activity. Regarding the few available studies, we assessed the association of minor variations of TSH concentrations and nutritional status in the first trimester of pregnancy.Materials and Methods:This cross-sectional descriptive and analytical study was performed on 150 primiparous healthy women. Demographic and family characteristics were collected using a researcher-administered questionnaire. Nutrients intake were extracted from a 72-h recall, and physical activity scores were determined by the pregnancy physical activity scale.Results:The prepregnancy body mass index (BMI) (β =0.022, P = 0.004) and participants' weight at 6–10 weeks of gestation (β =0.006, P = 0.024) were positively associated with TSH concentrations, while total physical activity score was negatively correlated (β = ‒0.006, P = 0.047). We did not find any significant association between TSH values and energy-adjusted nutrients intake (P > 0.05).Conclusion:We suggest that differences in TSH concentrations within normal range in the first trimester are correlated with gaining weight, physical activity level, and prepregnancy BMI. TSH concentration and consequently thyroid function may influence on gestational weight gain or vice versa.