Thyroid Therapy Research Articles

Monitoring of Thyroid Malfunction and Therapies in Pregnancy and the Postpartum Period: A Systematic Updated Critical Review of the Literature.

From the very beginning of pregnancy, the maternal thyroid has to adapt to increased thyroid hormone secretion of up to 50%. This is paralleled by changes in thyroid-stimulating hormone secretion and by the thyroid-topic action of human chorionic gonadotropin. Thus, hypothyroidism and hyperthyroidism may occur. Many women exhibit preexisting thyroid diseases. This review tries to add the most recently published approaches to diagnosing thyroid malfunction in pregnancy to existing guidelines. Different literature-based approaches to diagnosing thyroid malfunction during pregnancy and the postpartum period were applied. To diagnose thyroid malfunction in pregnancy, trimester-specific reference ranges for thyroid-stimulating hormone and T4 are used. Definitions of thyroid malfunction are given. Treatment schedules for various thyroid diseases were reviewed and, on the basis of recent findings, were revised where necessary. For a daily clinical workup, this outline not only suggests diagnostic and therapeutic steps but also refers to frequent pitfalls and misinterpretations of laboratory data. Although the body of knowledge is increasing rapidly, the authors believe that this review is able to present new ideas concerning diagnostic and therapeutic tools for thyroid malfunction in pregnancy and the postpartum period. Nevertheless, there seems to remain room for individual approaches based on the personal experience of physicians who deal with these issues regularly.

Thyroid Therapy or Dysfunction in Athletes: Is it Time to Revisit the Clinical Practice Guidelines?

Recent media have highlighted the controversy surrounding treatment of elite athletes for hypothyroidism. The World Anti-Doping Agency denied a request by the United States Anti-Doping Agency to ban the use of thyroid medication. At present, there is no scientific evidence that thyroid medication has the potential to enhance performance. Clinical practice guidelines are not definitive in regard to what classifies a patient as having hypothyroidism. Thyroid-stimulating hormone and free T4 are recommended to screen for thyroid disease; however, the thyrotropin-releasing hormone stimulation test is still advocated by some for detecting the earliest stages of hypothyroidism. Hypothyroidism has been demonstrated to reduce cardiopulmonary function and result in musculoskeletal symptoms, such as fatigue and muscle stiffness. Symptoms of hypothyroidism, including depression, fatigue, and impaired sleep, are similar to those reported in overtraining. These patients may have hypothalamic-pituitary dysfunction that may complicate interpretation of basal thyroid-stimulating hormone and free T4. To date, no association has been identified between training state and hypothyroidism. Research to more clearly define hypothyroidism using provocative testing, evaluate the potential for thyroid medication to enhance performance, and examine whether training may induce hypothyroidism in athletes is desirable.

Considering sex-specific adverse drug reactions should be a priority in pharmacovigilance and pharmacoepidemiological studies

Considering sex-specific adverse drug reactions should be a priority in pharmacovigilance and pharmacoepidemiological studies

Cross-sectional analysis of trace element status in thyroid disease

BackgroundThe synthesis of thyroid hormone depends on a set of trace elements, most importantly selenium and iodine. The dietary supply with certain micronutrients is limited in many areas of the world, including central Europe and large parts of Asia and Africa. Moreover, both thyroid disease risk and therapy effects are modulated by trace element supply and status. ObjectiveAssessment of trace element status in thyroid patients in a European metropolis. Material and MethodsAdult patients visiting a medical praxis in Berlin, Germany, were enrolled into a cross-sectional analysis, and serum samples were obtained from thyroid patients (n = 323) with different conditions including goitre, hypothyroidism, malignancy or autoimmune thyroid disease. Trace elements (iodine, selenium, copper and zinc) were assessed by ICP-MS/MS or total reflection X-ray analysis, along with two protein biomarkers of selenium status (selenoprotein P, glutathione peroxidase), and compared to the clinical phenotype. ResultsThe patients displayed relatively low serum zinc and selenium concentrations as compared to a set (n = 200) of healthy subjects (zinc; 1025+/-233 vs. 1068+/−230 μg/L, p < 0.01, selenium; 76.9+/18.8 vs. 85.1+/−17.4 μg/L, p < 0.0001). A high fraction of patients (37.5%) was classified as selenium-deficient (serum selenium concentrations <70 μg/L), in particular the patients with thyroid malignancy (59%). Serum copper was not different between the groups, and total serum iodine concentrations were unrelated to thyroid disease. Explorative statistical analyses yielded no significant interactions between the trace elements and disease parameters, except for free thyroxine inversely correlating to the copper/selenium ratio. ConclusionsIn adult thyroid patients, there is no relation of circulating copper, iodine, selenium or zinc concentrations to thyroid hormone. However, a large fraction of German thyroid patients displays a considerable selenium deficit, known to constitute a disease risk potentially impairing convalescence and aggravating autoimmune disease processes. It appears advisable to testing thyroid patients for selenium deficiency, and once diagnosed, an increased supply via dietary counselling or active supplementation should be considered.

Hypothyroid Symptoms in Levothyroxine-Treated Patients.

Approximately 15% of patients with hypothyroidism are dissatisfied with their treatment due to persistence of residual symptoms associated with hypothyroidism. The purpose of this study was to compare thyroid symptoms using the hypothyroid symptom scale (HSS) in patients receiving stable thyroid therapy for 6 months to patients without hypothyroidism. The HSS was used to identify the percentage of levothyroxine-treated hypothyroid patients with residual or persistent hypothyroid symptoms. Patients included in the study had hypothyroidism and were receiving a stable/maintenance dose of levothyroxine sodium therapy, unchanged for at least 6 months. A control group of patients were included if they did not have an active prescription for thyroid hormone therapy. The HSS was administered via phone or face-to-face interactions. Patients were asked to score 10 symptoms over the past month on a scale of 0 to 4 (e.g., 0, absence of, to 4, severe symptoms). Results were analyzed using descriptive and inferential statistics. T-tests and chi-squared analysis were used to assess differences in continuous and categorical variables. A total of 68% of the contacted patients responded to the survey. A total of 302 patients were in the intervention group and 273 were in the control group. The mean total HSS scores between groups were significantly higher in the treatment compared to the control group (13.92 ± 10.91 vs.10.07 ± 7.85; P < 0.001). Significantly more patients receiving thyroid hormone therapy experienced residual thyroid symptoms compared to control patients. Attempts should be made to offer alternatives for hypothyroid patients with persistent symptoms.

Estimation of thyroid volume from scintigraphy through 2D/3D registration of a statistical shape model

Accurate measurement of thyroid volume is important for thyroid disease diagnosis and therapy. In nuclear medicine, the thyroid volume is usually estimated from scintigraphy images using empirical equations. However, due to the lack of volumetric information from the scintigraphy image, the accuracy of equation-based estimation is imperfect. To solve this problem, this paper proposes a method which registers a 3D thyroid statistical shape model (SSM) to a single-view scintigraphy image to achieve more accurate volume estimation. The SSM was constructed based on a training set of segmented 3D CT images, and the thyroid shape variations between the training subjects were modelled using the point distribution model. For thyroid volume estimation, the SSM was projected into the scintigraphy image of the target patient, and then the projected model shape was nonrigidly registered with the patient’s scintigraphy image. The resultant 2D deformation file was back-projected to 3D space to guide the deformation of the 3D SSM. This process was repeated iteratively until convergence, and the volume of the finally deformed SSM was considered as the estimation of the patient’s thyroid volume. For validation, this method was evaluated based on a test set of 20 scintigraphy images, achieving an estimation error of −2.10% ± 5.20% which was much less than the error of the conventional equation-based method (35.76% ± 15.20%) based on the same test set. The robustness of this method was further tested using a challenging case, i.e. a scintigraphy image with a large thyroid tumor. For this case, the volume estimation error was only 6.08%. Our method has significantly improved the accuracy of thyroid volume estimation from scintigraphy images, and it will enhance the value of scintigraphy imaging for thyroid disease diagnosis and radioiodine therapy.

SAT-622 Rhabdomyolysis: A Rare Initial Presentation of Hypothyroidism

Introduction: Hypothyroidism is associated with a spectrum of musculoskeletal abnormalities as thyroid hormone signaling plays an integral role in skeletal muscle development and contractility. Mild to moderate CK elevation is present in majority of patients with symptomatic hypothyroidism. Overt rhabdomyolysis leading to acute kidney injury as a presentation of undiagnosed hypothyroidism is very rare. We present one such case. Case Description: 47-year-old African American woman with past medical history of non-insulin dependent diabetes and hypertension presented with myalgias and generalized edema in bilateral upper and lower extremities for the past 2 months. Outpatient labs revealed a Creatinine Kinase (CK) level of more than 10,000 U/L and an elevated creatinine level at 2 mg/dL. There was no history of trauma, immobilization, abnormal body movements, new drug use or recent fevers. At presentation, vital signs were stable. Physical examination showed non-pitting edema in bilateral upper and lower extremities. Initial work up revealed a creatinine of 2.15 mg/dL and CK level of 9173 U/L. Serum electrolytes were normal. Urine tested negative for myoglobin. Chest X ray and EKG were normal. Further testing revealed a TSH level of 148.7 mcIU/ml with T3 of <0.40 ng/dl and an undetectable T4 level. A diagnosis of primary hypothyroidism with rhabdomyolysis leading to acute kidney injury was made. She was treated with aggressive fluid resuscitation. She was also started on thyroid hormone supplementation with oral Levothyroxine 200 mcg/day. After initiation of treatment, the Creatinine levels trended down to 1.5 mg/dl. The CK levels trended down to 3600 U/L in 6 days after which she was discharged from the hospital. The patient was followed as an outpatient with gradual reduction of the CK levels over months. CK levels after 1 year were 154 U/L. The patient was continued on supplemental thyroid therapy. Discussion: Rhabdomyolysis is breakdown of muscle cells and release of muscle enzymes like Creatinine Kinase, electrolytes and myoglobin into the circulation. Among the various causes of Rhabdomyolysis, the most common are crush injuries, immobilization, seizures, heat stroke, sepsis and drugs like Statins, Colchicine and toxins like alcohol. Endocrinopathies like Hypothyroidism, Hyperthyroidism, Pheochromocytoma and Diabetes Ketoacidosis have been associated with rhabdomyolysis, but they tend to get ignored due to a lower incidence. Hypothyroidism is associated with elevation in CK levels in about 57-90% patients but the level of CK elevation is only mild, less than 10 times the upper limit of normal. Our case describes an uncommon initial presentation of hypothyroidism leading to overt rhabdomyolysis and acute kidney injury. It emphasizes the importance of checking a thyroid profile in a patient with acute elevation in muscle enzymes without an identifiable trigger.

Donor Hormonal Thyroid Therapy is Associated with Increased Risk of Primary Graft Dysfunction after Heart Transplantation

Donor Hormonal Thyroid Therapy is Associated with Increased Risk of Primary Graft Dysfunction after Heart Transplantation

Concordance assessment of self-reported medication use in the Netherlands three-generation Lifelines Cohort study with the pharmacy database iaDB.nl: The PharmLines initiative.

BackgroundWhile self-reported data are commonly used as a source of medication use for pharmaco-epidemiological studies, such information is prone to forms of bias. Several previous studies showed that various factors like age, type of drug and data collection method may influence accuracy. We aimed to assess the concordance of the self-reported medication use that was documented at entry to the Lifelines Cohort Study, a three-generation follow-up study in the Netherlands that started in 2006 and included over 167,000 participants.Materials and methodsAs part of the PharmLines Initiative, we collected medication data from the Lifelines participants encoded according to the Anatomical Therapeutic Chemical (ATC) coding scheme and linked the data via Statistics Netherlands to the widely used and representative pharmacy prescription database of the University of Groningen, IADB.nl. Analyses were conducted at second level of ATC coding for all recorded medications as well as a top list of most used medications at drug-specific fifth level. Cohen’s kappa statistics were used to measure the concordance for all participants according to sex and age.ResultsThe level of concordance between the two data sources largely differed according to the therapeutic class. Medication used for the cardiovascular system and diabetes, thyroid therapy, bisphosphonates and anti-thrombotic drugs showed a very good agreement (κ>0.75). Medication as needed or prone to stigmatization bias showed a moderate agreement (κ=0.41–0.60), whereas medications used for short periods of time showed a fair agreement (κ=0.0–0.4). Concordance was similar for males and females, but younger adults tended to have lower concordance rates than older adults.ConclusionThe self-reported method was valid for capturing prevalent chronic medication use at one moment in time, but invalid for medication used for short periods of time. There is no effect of sex on the agreement, and more studies are needed on the influence of age. Future pharmaco-epidemiological studies should preferably combine the two data sources to achieve the highest accuracy of drug exposure rates.

P082] New software for dosimetry in radioiodine therapy

Purpose An increasing interest in dosimetry for planning and verification in radionuclide therapy induces the need for an user-friendly, reliable and flexible software for dosimetric calculations. As the methods are not fully developed yet, such software must also be easy to modify and extend to involve possible procedure changes while keeping user-friendliness for a large-scale use. This work presents PTKManager as an application created for this purpose. Methods The software is written in C++. Its structure is modular, i.e. data processing workflow consists of modules that can be easily appended, removed or replaced from the workflow as plugins. The output of a module may be used as the input of any succeeding module. The modules are stored as functions in dynamic-linked libraries and are dynamically loaded, so their inclusion to the workflow does not require installation. The user may add own modules written in any compiled programming language with pointer support. The application is designed as a NEMA DICOM SCU/SCP station so a direct communication with PACS or acquisition equipment is possible. Results Modules for calculations based on EANM Dosimetry Guidelines for radioiodine therapies are able to store the measured and calculated data in the form of NEMA DICOM structured reports. The application has been used for dose verification in radioiodine thyroid therapies at University Hospital in Olomouc. Measured data in lesions or in whole-body are converted to activities using user-defined calibration factors, fitted to a biokinetic model using the sum-of-squares or chi-squared minimization and doses are estimated using user-defined S-factors. Conclusions The presented software may be a useful application in standardization and simplification of large-scale dosimetry, to test new methods or just to keep records of patient doses in DICOM files.

OA203] Assessment of radiation exposure in a newly formed nuclear medicine department

Purpose In an oncology nuclear medicine department, radioisotopes are not only used for tumor detecting, staging, evaluation of therapy response but also for therapeutic purposes. This study documents the radiation exposure of departmental staff, related to cyclotron operation and service during the production and injection of 18F radiopharmaceuticals for PET/CT examination. In addition, it investigates exposure in a multiple holding tank system used for the storage of 131I waste generated from patients undergoing thyroid therapy, in order to optimize environmental protection procedures. Methods Measurements for the dose rates of neutrons and photons in the room of ABT-BG-75 self-shielded mini-cyclotron were recorded during bombardment for 18F-FDG production using a neutron detector and a scintillation dosimeter. The correlation between the duration of bombardment and required time to reach a dose rate equal to background level was investigated. An electronic dosimeter was used to record staff exposure for 18F production, dispensing, administration and imaging using PET-CT. Finally, the decay rate of 131I waste was measured using a dose rate meter positioned in the decay tank system of the radioactive iodine isolation ward. Results The time required for the cyclotron room to reach background level following completion of bombardment (3 × 50 min each) was approximately 2 h. The dose rate from neutrons was found to be negligible and from photons was less than 7.5 μ Sv/h. Therefore, personnel can safely enter the room during bombardment. The staff mean whole-body dose per 18F-administered patient was 1–2 μ Sv, depending on patient condition. The values obtained from the 131I radioactive waste stored in a delay tank system were comparable with theoretical values. Conclusion This study is useful for optimizing radiation exposure in an oncology nuclear medicine department. It is shown that during 18F production exposure is mostly attributed to photons. The level of the dose permits staff entry into the cyclotron room. Staff responsible for administration received 1–2 μ Sv per 18F-patient, considered to be on the lower end of the acceptable limit for a radiation worker. The study also documents the decay rate of 131I waste over the period which the suggested activity level for release in the environment is reached.

Thyrotropin Receptor Antibodies-An Overview.

Thyroid autoimmunity affects approximately 5% of the population, and its investigation relies heavily on the use of autoantibodies. Thyroid stimulating hormone receptor (TSHR) autoantibodies (TRAb) play a central role in the evaluation of Graves disease (GD), Graves ophthalmopathy (GO) and pretibial myxedema (PTM). However, there is still controversy regarding overall TRAb assay diagnostic accuracy and their prognostic utility. We reviewed and analyzed the literature reporting TRAb assays and their clinical utility. Current assays measure the overall TRAb titer in a competitive manner (TSH binding inhibiting immunoglobulin assay) or biologic activity of the stimulating TSHR autoantibodies (thyroid stimulating immunoglobulin assay). Both types of assays have improved over time with advances in sensitivity and specificity. TRAb are particularly relevant in hyperthyroidism cases where use of iodinated contrast is not an option (e.g., pregnancy or recent use of iodinated contrast) or in cases of euthyroid eye disease, suspicious for GO. Third generation TRAb assays are useful for therapy selection in GD, prognostic predictions in GO and risk prediction for fetal and neonatal thyrotoxicosis. Given the pathogenic role of TRAb, we expect that the future will bring useful evidence regarding their predictive role with respect to efficacy of therapeutic modalities for GO and PTM. We also hope to better understand the role of blocking and neutral antibodies against TSHR, and harness that ability for modulation of thyroid function or therapy of differentiated thyroid carcinoma managed with TSH suppression. Thyroid autoimmune diseases have seen tremendous gains in understanding their pathophysiology, largely antibody mediated. Better TRAb testing is becoming a springboard for providing individualized patient care.

Risk factors for discontinuation of thyroid hormone replacement therapy in early pregnancy: a study from the Norwegian Mother and Child Cohort Study and the Medical Birth Registry of Norway.

Approximately 3-5% of pregnant women have hypothyroidism. Despite the potential impact of untreated hypothyroidism on infant neurodevelopment, few studies have investigated the risk factors associated with discontinuation of thyroid hormone replacement therapy (THRT) in pregnancy. We aimed to identify such factors in a population of women using THRT prior to pregnancy. Data from the Norwegian Mother and Child Cohort Study were linked to records in the Medical Birth Registry of Norway. Pregnant women with hypothyroidism prior to pregnancy were categorized as discontinuers or continuers of THRT in pregnancy. The main analysis used generalized estimating equations based on multiply imputed data. Of 86 848 enrolled pregnant women, 2720 (3.2%) had a medically confirmed thyroid disorder and/or reported use of thyroid therapy. More than half (n = 1587; 57.8%) used THRT prior to pregnancy; of these, 207 (13.0%) discontinued and 1380 (86.9%) continued THRT during early pregnancy. Having a non-medicated mental disorder [odds ratio (OR) 1.64, 95% CI 1.03-2.63] and non-compliance with recommended nutritional supplementation (OR 2.51, 95% CI 1.82-3.47) increased the odds of discontinuing THRT. Women medicated for somatic comorbidities (OR 0.56, 95% CI 0.33-0.98) had a 44% decreased odds of discontinuing THRT. In Norway, around 13% of women with hypothyroidism discontinue THRT in early pregnancy. For discontinuers, non-medicated mental comorbidity and non-compliance with nutritional supplements presented increased risk, whereas having a medicated somatic disorder was protective. Health professionals advising women with hypothyroidism should be aware of risk factors associated with THRT discontinuation.

Galectin-3: The Impact on the Clinical Management of Patients with Thyroid Nodules and Future Perspectives.

Galectins (S-type lectins) are an evolutionarily-conserved family of lectin molecules, which can be expressed intracellularly and in the extracellular matrix, as well. Galectins bind β-galactose-containing glycoconjugates and are functionally active in converting glycan-related information into cell biological programs. Altered glycosylation notably occurring in cancer cells and expression of specific galectins provide, indeed, a fashionable mechanism of molecular interactions able to regulate several tumor relevant functions, among which are cell adhesion and migration, cell differentiation, gene transcription and RNA splicing, cell cycle and apoptosis. Furthermore, several galectin molecules also play a role in regulating the immune response. These functions are strongly dependent on the cell context, in which specific galectins and related glyco-ligands are expressed. Thyroid cancer likely represents the paradigmatic tumor model in which experimental studies on galectins’ glycobiology, in particular on galectin-3 expression and function, contributed greatly to the improvement of cancer diagnosis. The discovery of a restricted expression of galectin-3 in well-differentiated thyroid carcinomas (WDTC), compared to normal and benign thyroid conditions, contributed also to promoting preclinical studies aimed at exploring new strategies for imaging thyroid cancer in vivo based on galectin-3 immuno-targeting. Results derived from these recent experimental studies promise a further improvement of both thyroid cancer diagnosis and therapy in the near future. In this review, the biological role of galectin-3 expression in thyroid cancer, the validation and translation to a clinical setting of a galectin-3 test method for the preoperative characterization of thyroid nodules and a galectin-3-based immuno-positron emission tomography (immuno-PET) imaging of thyroid cancer in vivo are presented and discussed.

Differences in drug use between men and women: an Italian cross sectional study

BackgroundDrugs are the most important treatment option for most diseases, and the majority of medical consultations result in a prescription. Women and men receive different drug prescriptions and differ in therapeutic response to pharmacological therapy. This disparity is due to biological factors (sex differences) or/and behavior, lifestyle and life experience (gender differences). Sex differences in drug use have been demonstrated in several therapeutic areas; however, there is a lack of overviews on sex and gender differences of drug use in an entire population.MethodsWe conducted a descriptive cross - sectional drug use study, involving the entire Italian population in 2012, aimed at showing and analyzing differences between men and women as regards their exposure to drugs. The data source was IMS LifeLink Treatment DynamicsTMLRx Database and it included all prescribed drugs reimbursed by the Italian National Healthcare System in 2012 and covered 90% of the entire Italian population.The information about the prescriptions was stratified by men and women and age. Drug consumption was expressed as DDD/ 1000 ab die. Exposure to drug prescriptions was expressed as period prevalence (the proportion of the population dispensed ≥1 prescription in 2012 per 1000 inhabitants). Differences of prevalence between men and women were expressed as crude and age adjusted risk ratios with 95% CI.ResultsOur findings suggested that the largest differences in drug prescriptions regarded drugs affecting bone structure and mineralization (RR 15.9), calcium (RR 8.6) and thyroid therapy (RR 5.4), dispensed more to women than men. Otherwise ACE inhibitors were more commonly used in men.ConclusionsThis is the first study exploring difference in drug use between men and women and carried out on the entire Italian population. Our findings showed substantial differences between men and women in term of prevalence of drug prescriptions. Some differences in drug use may be explained by sex differences (variations in disease prevalence and severity, pathophysiology, or by other biological differences), other differences need further investigation to explain the apparent lack of a rational medical explanation for some findings.The findings may subsequently be used to plan future studies to address differences suggesting inequity in treatment approaches.

Analysis of the clinical effect of thyroid tablets combined with superior thyroid in the treatment of patients with hypothyroidism

Objective Investigate the clinical effect of thyroid tablets combined with superior thyroid therapy in the treatment of hypothyroidism. Methods 90 patients with hypothyroidism were selected and divided into control group and observation group by random digit table, the control group was given Thyroid Tablets treatment, the observation group was treated with thyroid tablets combined with the use of left thyroid hormone tablets.To investigate the clinical efficacy of 1 groups of patients after two years of treatment, the main indicators of changes and adverse reactions, etc. Results After treatment, the total efficiency of the observation group 95.6% compared with the control group 82.2%, the difference was statistically significant (χ2=1.995, P 0.05). Conclusion The combination of thyroid tablets and superior thyroid in the treatment of hypothyroidism can significantly improve the clinical symptoms of patients, improve clinical efficacy, and the safety is better, has a larger clinical significance. Key words: Hypothyroidism; Thyroid Tablets; Superior thyroid

Hormone Responsive Hashimoto Encephalopathy: A Case of Hashimoto Encephalopathy Treated with only Oral Thyroid Medication and Symptomatic Therapy for Seizures and Psychosis, but without Steroids

Hashimoto encephalopathy is a rare disease associated with autoimmune thyroiditis. Symptoms may include delirium, encephalopathy, seizures, and psychosis. Pathophysiology of this disease is not completely understood. This condition is often under-diagnosed if not suspected and should be considered in patients with diverse neuropsychiatric manifestations in whom no obvious etiology of encephalopathy can be determined. Anti-thyroid antibodies and thyroid peroxidase antibodies are crucial for diagnosis. Along with supportive management, empiric steroid treatment is usually administered as soon as infectious and other causes are ruled out. We report a case of Hashimoto thyroiditis which presented with agitation, psychosis, hallucinations, complex partial seizures. In this case the disease was controlled with only oral thyroid therapy and supportive management with antiepileptic drugs and antipsychotic drugs, but without the use of steroids.

Treatment outcome and predictors of better response to thyroxin in hypothyroid patients with sleep apnea syndrome in Zagazig University hospital

BackgroundMany studies suggest that sleep-disordered breathing (SDB) is common among patients with hypothyroidism. Obstructive sleep apnea syndrome (OSAS) is characterized by complete cessation of inspiratory flow (apnea) or upper airway airflow limitation (hypopnea) with increased respiratory muscle activity, which is repeatedly observed during sleep. Hypothyroidism and OSA have overlapping clinical presentations. Excessive daytime somnolence, apathy and lethargy are known to occur in patients with hypothyroidism. AimThis study was designed to detect predictors for better response to thyroxin therapy in hypothyroid patients presented with OSAS and to pick up features of other hypothyroid patients who still presented with obstructive sleep apnea and remain in need of CPAP beside thyroxin therapy, after euthyroid state had been reached. Settings and designThis randomized controlled clinical trial study was conducted in Chest and Internal Medicine departments, Zagazig University Hospitals. Patients and methodsA total of 130 patients, 65 with hypothyroidism had manifestations of OSA confirmed by sleep study (1st polysomnography) (group I) and 65 euthyroid patients with manifestations of OSA as a control subjects, were treated by CPAP (group II). After reaching euthyroid state, another sleep study (2nd polysomnography) was done, then patients were subdivided into : 40 patients whom polysomnographic study improved markedly after thyroxin therapy and advised to continue on thyroxin replacement (IA subgroup) and 25 patients showed no significant improvement and planned for CPAP therapy along with thyroid therapy (IB subgroup). ResultsNeck circumference, BMI and Epworth score were statistically significantly higher in hypothyroid group (p≤0.002, <0.001, 0.01 respectively), hypothyroid patients associated with sleep apnea more likely to have statistically longer stage 3 duration and more frequent snoring (p<0.001). 40 patients who were adviced to continue on thyroxin therapy alone had significant improvement in all sleep parameters. By retrograde analysis, patients who advised to continue on hormonal therapy alone (n=40) had statistically significant less neck circumference (p=0.022), more lower levels of TSH and higher levels of FT4 (p<0.001, 0.008) in comparison to patients continued on hormonal therapy and CPAP (n=20). ConclusionsSome hypothyroidism patients with OSA will improve on hormonal therapy alone but other will continue to need CPAP. Neck circumference, free T4 and TSH levels may help us in predicting the response of these patients.

Nuclear Molecular and Theranostic Imaging for Differentiated Thyroid Cancer.

Traditional nuclear medicine is rapidly being transformed by the evolving concepts in molecular imaging and theranostics. The utility of new approaches in differentiated thyroid cancer (DTC) diagnostics and therapy has not been fully appreciated. The clinical information, relevant to disease management and patient care, obtained by scintigraphy is still being underestimated. There has been a trend towards moving away from the use of radioactive iodine (RAI) imaging in the management of the disease. This paradigm shift is supported by the 2015 American Thyroid Association Guidelines (1). A more systematic and comprehensive understanding of disease pathophysiology and imaging methodologies is needed for optimal utilization of different imaging modalities in the management of DTC. There have been significant developments in radiotracer and imaging technology, clinically proven to contribute to the understanding of tumor biology and the clinical assessment of patients with DTC. The research and development in the field continues to evolve, with expected emergence of many novel diagnostic and therapeutic techniques. The role for nuclear imaging applications will continue to evolve and be reconfigured in the changing paradigm. This article aims to review the clinical uses and controversies surrounding the use of scintigraphy, and the information it can provide in assisting in the management and treatment of DTC.

Retrospective Biological Dosimetry at Low and High Doses of Radiation and Radioiodine Impact on Individual Susceptibility to Ionizing Radiation.

Iodine-131 (I-131) is often used in thyroid diagnostics and therapy. External and internal exposure to radioiodine can lead to molecular and cellular damage in peripheral blood lymphocytes. The aim of this study was to explore the influence of low and high doses of I-131 on susceptibility to ionizing radiation. Study groups consisted of 30 individuals free of thyroid diseases, 41 patients exposed diagnostically to low doses of I-131, and 37 hyperthyroidism patients exposed therapeutically to high doses. The standardized DNA repair competence assay was used to test the efficacy of the fast DNA repair process in G0 cells. Cytogenetic preparations were made in fresh blood samples before and after challenging cells in vitro with X-ray dose. The frequency of sister chromatid exchanges (SCE) and percentage of cells with significantly elevated numbers of SCE were used as cytogenetic biomarkers associated to homologous recombination and compared to reported earlier cytogenetic biomarkers of cancer risk. Strong individual variation in the biomarkers is observed in all investigated groups before and after challenging. Nevertheless, the efficiency of post challenging fast repair is significantly high in the patients exposed to diagnostic I-131 doses than in unexposed control group and linked to decreased cytogenetic damage. However, 5 weeks after administration of therapeutic doses, significant increases of unrepaired post challenging DNA and cytogenetic damages were observed indicating a health risk. Results also suggest that the appearance of cancers in immediate families might influence DNA repair differently in patients exposed to low than to high doses.