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Thyroid-stimulating Hormone (thyroid-stimulating + hormone)
Kinds of Thyroid-stimulating Hormone Selected AbstractsThyroid-Stimulating Hormone Restores Bone Volume, Microarchitecture, and Strength in Aged Ovariectomized Rats*,,§JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2007T Kuber Sampath PhD Abstract We show the systemic administration of low levels of TSH increases bone volume and improves bone microarchitecture and strength in aged OVX rats. TSH's actions are mediated by its inhibitory effects on RANKL-induced osteoclast formation and bone resorption coupled with stimulatory effects on osteoblast differentiation and bone formation, suggesting TSH directly affects bone remodeling in vivo. Introduction: Thyroid-stimulating hormone (TSH) receptor haploinsufficient mice with normal circulating thyroid hormone levels have reduced bone mass, suggesting that TSH directly affects bone remodeling. We examined whether systemic TSH administration restored bone volume in aged ovariectomized (OVX) rats and influenced osteoclast formation and osteoblast differentiation in vitro. Materials and Methods: Sprague-Dawley rats were OVX at 6 months, and TSH therapy was started immediately after surgery (prevention mode; n = 80) or 7 mo later (restoration mode; n = 152). Hind limbs and lumbar spine BMD was measured at 2- or 4-wk intervals in vivo and ex vivo on termination at 8,16 wk. Long bones were subjected to ,CT, histomorphometric, and biomechanical analyses. The direct effect of TSH was examined in osteoclast and osteoblast progenitor cultures and established rat osteosarcoma-derived osteoblastic cells. Data were analyzed by ANOVA Dunnett test. Results: In the prevention mode, low doses (0.1 and 0.3 ,g) of native rat TSH prevented the progressive bone loss, and importantly, did not increase serum triiodothyroxine (T3) and thyroxine (T4) levels in aged OVX rats. In restoration mode, animals receiving 0.1 and 0.3 ,g TSH had increased BMD (10,11%), trabecular bone volume (100,130%), trabecular number (25,40%), trabecular thickness (45,60%), cortical thickness (5,16%), mineral apposition and bone formation rate (200,300%), and enhanced mechanical strength of the femur (51,60%) compared with control OVX rats. In vitro studies suggest that TSH's action is mediated by its inhibitory effects on RANKL-induced osteoclast formation, as shown in hematopoietic stem cells cultivated from TSH-treated OVX rats. TSH also stimulates osteoblast differentiation, as shown by effects on alkaline phosphatase activity, osteocalcin expression, and mineralization rate. Conclusions: These results show for the first time that systemically administered TSH prevents bone loss and restores bone mass in aged OVX rats through both antiresorptive and anabolic effects on bone remodeling. [source] Diurnal Change of Thyroid-Stimulating Hormone mRNA Expression in the Rat Pars TuberalisJOURNAL OF NEUROENDOCRINOLOGY, Issue 11 2007S. Aizawa Thyroid-stimulating hormone (TSH)-producing cells (TSH cells), which account for a large fraction of the cells in the rat pars tuberalis (PT), have been found to express MT1 melatonin receptor and mammalian clock genes at high densities. Although these findings suggest that TSH production in the rat PT is regulated by melatonin and/or the biological clock, there have been no studies focusing on the diurnal change and regulation mechanism of TSH production in the rat PT. Therefore, in the present study, we examined diurnal changes of in TSH, and ,-glycoprotein subunit (,GSU) mRNA expression and TSH immunoreactivity (-ir) in the rat PT, and also examined the relationship between melatonin and TSH production in vivo. Both TSH, mRNA expression and ,GSU mRNA expression in the PT showed diurnal variations: the expression levels were lowest at the light phase [Zeitgeber time (ZT)4] and high at the dark phase (ZT12 and ZT20). TSH-ir in the PT showed the lowest level at ZT4, as was found for mRNA expression. Interestingly, TSH-ir, which was confined to the Golgi apparatus at ZT4, spread to the cytoplasm, and most of the TSH cells in the PT were uniformly immunostained in the cytoplasm at ZT20. Despite the fact that chronic administration of melatonin suppressed TSH, and ,GSU mRNA expression, TSH-ir in the PT was significantly enhanced. These findings results clearly show that there are diurnal changes in TSH expression and accumulation in rat PT-TSH cells and suggest that these fluctuations are regulated by melatonin. [source] Pituitary and autonomic responses to cold exposures in manACTA PHYSIOLOGICA, Issue 4 2005J. Leppäluoto Abstract This review presents hormonal responses to various cold exposures and their calorigenic effects in man and some animals. Previous studies in rats have shown that cold exposures activate the hypothalamic-pituitary-thyroid axis. Increased thyroid hormone concentrations lead to heat production via general stimulation of metabolism (obligatory thermogenesis) and possibly via activation of thyroid hormone receptors and uncoupling protein 1 (UCP 1) and deiodinase enzyme genes in the brown adipose tissue (BAT). In human subjects long-term cold exposures do not seem to activate the pituitary-thyroid axis, but rather accelerate the elimination of triiodothyronine (T3), leading to low serum concentrations of free T3 hormone. In corollary to this a hypothyreotic condition with increased serum thyroid-stimulating hormone and impaired mood and cognitive performance can be observed after long-term cold exposures such as wintering. During cold exposures the sympathetic nerve system is activated and noradrenaline is released to blood circulation and to BAT, where it leads to production of cAMP, lipolysis and free fatty acids. Free fatty acids open the mitochondrial proton channel protein in BAT. Protons enter the mitochondria and inhibit ATP synthesis (uncoupling). By this way energy is transformed into heat (facultatory or adaptive thermogenesis). In adult human subjects the amount of BAT is small and adaptive thermogenesis (non-shivering thermogenesis) has a smaller role. UCP 1 with other uncoupling proteins may have other functions in the control of body weight, sugar balance and formation of reactive oxygen species. [source] Depressive relapse during lithium treatment associated with increased serum thyroid-stimulating hormone: results from two placebo-controlled bipolar I maintenance studiesACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2009M. A. Frye Objective:, To assess the relationship between depressive relapse and change in thyroid function in an exploratory post hoc analysis from a controlled maintenance evaluation of bipolar I disorder. Method:, Mean thyroid-stimulating hormone (TSH) and outcome data were pooled from two 18-month, double-blind, placebo-controlled, maintenance studies of lamotrigine and lithium monotherapy. A post hoc analysis of 109 subjects (n = 55 lamotrigine, n = 32 lithium, n = 22 placebo) with serum TSH values at screening and either week 52 (±14 days) or study drop-out was conducted. Results:, Lithium-treated subjects who required an intervention for a depressive episode had a significantly higher adjusted mean TSH level (4.4 ,IU/ml) compared with lithium-treated subjects who did not require intervention for a depressive episode (2.4 ,IU/ml). Conclusion:, Lithium-related changes in thyroid function are clinically relevant and should be carefully monitored in the maintenance phase of bipolar disorder to maximize mood stability and minimize the risk of subsyndromal or syndromal depressive relapse. [source] Prevalence of autoimmune diseases in islet transplant candidates with severe hypoglycaemia and glycaemic lability: previously undiagnosed coeliac and autoimmune thyroid disease is identified by screeningDIABETIC MEDICINE, Issue 2 2007M. Walter Abstract Aims, Autoimmune diseases such as Addison's or coeliac disease can contribute to hypoglycaemia or malabsorption and are more common in Type 1 diabetes (T1DM). This brief report describes the prevalence of known and newly detected autoimmune disease in clinical islet transplant candidates with longstanding T1DM and severe hypoglycaemia and/or glycaemic lability who are routinely screened for coexisting autoimmune disease. Methods, One hundred and twenty-four C-peptide negative T1DM subjects [77 (62%) female, mean age 44 ± 9 years, diabetes duration 28 ± 11 years, body mass index 24.9 ± 3.5 kg/m2] with indications for clinical islet transplantation at the University of Alberta were screened for autoimmune disease by history and measurement of anti-transglutaminase antibodies (positive > 10 U/ml), 09.00 h cortisol (followed by adrenocorticotrophic hormone-stimulation if < 495 nmol/l) and thyroid-stimulating hormone to determine the prevalence of coeliac disease, Addison's disease and autoimmune thyroid disease, respectively. Results, Forty per cent of subjects had one or more coexisting autoimmune disease. The prevalence of autoimmune disease was 35%, coeliac disease 8% and Addison's disease 1.6%. In 11 individuals (9%), one or more autoimmune disease were newly detected (seven coeliac disease and five thyroid disease). Seven of 10 cases of coeliac disease were newly detected. A gluten-free diet in individuals with newly diagnosed coeliac disease reduced gastrointestinal symptoms, but indications for clinical islet cell transplantation persisted. Conclusions, Coexisting autoimmune disease is common in candidates for clinical islet cell transplantation. Screening in this group identified a substantial number of previously unrecognized cases. Clinicians should consider the presence of autoimmune disease even in the absence of classical symptoms. [source] Gravity-induced convective flow in microfluidic systems: Electrochemical characterization and application to enzyme-linked immunosorbent assay testsELECTROPHORESIS, Issue 21-22 2004Patrick Morier Abstract A way of using gravity flow to induce a linear convection within a microfluidic system is presented. It is shown and mathematically supported that tilting a 1 cm long covered microchannel is enough to generate flow rates up to 1000 nL·min -1, which represents a linear velocity of 2.4 mm·s -1. This paper also presents a method to monitor the microfluidic events occurring in a covered microchannel when a difference of pressure is applied to force a solution to flow in said covered microchannel, thanks to electrodes inserted in the microfluidic device. Gravity-induced flow monitored electrochemically is applied to the performance of a parallel-microchannel enzyme-linked immunosorbent assay (ELISA) of the thyroid-stimulating hormone (TSH) with electrochemical detection. A simple method for generating and monitoring fluid flows is described, which can, for instance, be used for controlling parallel assays in microsystems. [source] Impaired estrogen-induced negative feedback on gonadotropin secretion in patients with gonadotropin-secreting and nonfunctioning pituitary adenomasEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 5 2002A. Lania Abstract Background Several in vitro studies suggest that gonadotropin-secreting pituitary adenomas (Gn-omas) and non functioning pituitary adenomas (NFPA) originate from gonadotroph cells. Patients with Gn-oma and NFPA frequently show abnormal gonadotropin response to TRH. The aim of the study was to investigate whether the estrogen-induced negative feedback is operating in either patients with Gn-oma or NFPA. Materials and methods Serum gonadotropin levels were evaluated at 24 h after ethinylestradiol administration (1 mg per os; EE2 test) in seven patients with a diagnosis of Gn-oma, based on the presence of high follicle-stimulating hormone (FSH) and/or lutenising hormone (LH) levels with normal or high levels of sex steroids, in 22 patients with NFPA with normal or low levels of gonadotropin and sex steroids, and 30 sex- and age-matched healthy subjects. A normal response to EE2 test was arbitrarily defined as a serum LH and FSH decrease of at least 40 and 30% below basal levels. Results Among patients with Gn-oma, only one had a normal FSH inhibition and another, a normal LH inhibition. Among the 22 patients with NFPA, the EE2 test caused a normal FSH or LH reduction in 10 and 15, respectively, while a normal reduction of both FSH and LH was observed in nine. Conclusions The study demonstrates that estrogen-induced negative feedback of gonadotropin secretion is disrupted in almost all patients with Gn-oma and in half of those with NFPA. This defective feedback is reminiscent of the resistance to thyroid hormones and glucocorticoids observed in patients with thyroid-stimulating hormone- (TSH-) and adrenocorticotropic hormone- (ACTH-)secreting adenomas, respectively. [source] Thyroid hormone resistance: the role of mutational analysisINTERNAL MEDICINE JOURNAL, Issue 11 2006C. M. Florkowski Abstract The finding of increased thyroxine (T4) and tri-iodothyronine (T3) levels in a patient with normal or increased thyroid-stimulating hormone is unexpected and presents a differential diagnosis between a thyroid-stimulating hormone-secreting pituitary adenoma, generalized resistance to thyroid hormone (RTH) and laboratory artefact. Without careful clinical and biochemical evaluation, errors may occur in patient diagnosis and treatment. In the case of RTH, mutation of the thyroid hormone receptor beta gene results in generalized tissue resistance to thyroid hormone. As the pituitary gland shares in this tissue resistance, euthyroidism with a normal thyroid-stimulating hormone is usually maintained by increased thyroid hormones. To date, we have identified eight pedigrees in New Zealand with mutations in the thyroid hormone receptor beta gene, including two novel mutations. Mutational analysis of the thyroid hormone receptor beta gene allows definitive diagnosis of RTH, potentially avoiding the need for protracted and expensive pituitary function testing and imaging. Mutational analysis also enables family screening and may help to avoid potential misdiagnosis and inappropriate treatment. [source] Elevated thyroid hormone levels with normal or raised thyroid-stimulating hormone: a diagnostic and therapeutic dilemmaINTERNAL MEDICINE JOURNAL, Issue 7 2001I. M. Holdaway No abstract is available for this article. [source] Mucous membrane pemphigoid, thymoma, and myasthenia gravisINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 9 2000Haideh Yazdani Sabet In November 1997, approximately 1 year before being evaluated at the Mayo Clinic, Rochester, a 63-year-old woman presented with erosive tongue lesions that were diagnosed by her physician as oral lichen planus. The lesions responded well to 3 months of treatment with systemic and topical corticosteroids and topical antiyeast medication. She stopped taking the medications and had a relapse. A few months after the oral lesions developed, her left eyelid became ptotic. Results of magnetic resonance imaging of her brain were normal, and the ptosis resolved spontaneously after 2 weeks. One year later, her right eyelid began to droop, and the results of edrophonium testing were positive. She was prescribed prednisone, 30 mg daily, and pyridostigmine, as needed. The ptosis improved, but never fully resolved. Radiography revealed a left ,,thyroid nodule,'' but computed tomography did not show a mediastinal mass. She was advised to have the ,,nodule'' removed surgically and came to the Mayo Clinic, Rochester, for a second opinion. Her medical history was significant for the following: tinnitus, glaucoma, early bilateral cataracts, and long-standing hypertension, for which she took losartan, 50 mg twice daily. Other medications included: prednisone, 30 mg daily; pyridostigmine as needed; famotidine, 40 mg daily; and eyedrops for glaucoma. She denied any history of hyperthyroidism or hypothyroidism, head and neck irradiation, family history of thyroid disease, or diplopia. Hepatitis serologic studies revealed hepatitis B exposure and recovery, hepatitis C immunity, and a previous hepatitis A viral infection. On examination at the Mayo Clinic, Rochester, an erosive hypertrophic plaque was noted on the posterior dorsal half of the tongue, and vesicles and erythematous erosions on the hard and soft palates ( Fig. 1a). A lace-like white pattern was seen on the buccal mucosa bilaterally, and a small erosive patch on the left buccal mucosa ( Fig. 1b). Ocular and nasal mucous membranes were normal in appearance, and there were no pertinent skin findings. Dermatopathologic examination of an excisional biopsy specimen from the left dorsum of the tongue demonstrated an ulcer with epitheliomatous hyperplasia and a granulomatous reaction, presumably due to yeast infection. Silver staining showed hyphae and yeast at the base of the tongue ulcer. The results of the direct immunofluorescence study were negative and revealed no lichenoid changes on hematoxylin and eosin staining. Indirect immunofluorescence testing of the serum revealed a 1 : 80 titer of basement membrane zone antibodies, reflecting pemphigoid. This test was positive on repeat study. Salt-split skin on monkey esophagus revealed an epidermal pattern of basement membrane zone antibodies. Treatment included fluocinonide gel applied to the involved areas four times daily and oral antiyeast therapy (fluconazole, 200 mg once daily by mouth) while the rest of the evaluation was being completed. Figure 1(a). Erosive hypertrophic tongue plaque. Figure (b) ,. Erosive patch on the buccal mucosa. As part of the evaluation of the ptosis, a myasthenia gravis antibody panel was performed. It revealed the following abnormalities: striated muscle antibody at 1 : 480 (reference range, <1 : 60), acetylcholine receptor binding antibody at 6.33 nmol/L (reference range, ,,0.02 nmol/L), acetylcholine receptor blocking antibody at 31% (reference range, 0,25%), and acetylcholine receptor modulating antibody at 100% (reference range, 0,20%), suggesting thymoma. Treatment included pyridostigmine, 30,45 mg 3,4 times daily, to control the myasthenia symptoms, while the ill-defined neck mass was being evaluated. A mildly enlarged thyroid was noted on physical examination. Hematology panel revealed thyroid-stimulating hormone (TSH) levels in the low normal range; the thyroid microsomal antibody was normal. Chest radiography showed minor tracheal deviation, and a previous computed tomogram showed what appeared to be a 3-cm enlarged mass in the thyroid. Ultrasonographically guided thyroid biopsy did not show malignancy, but a benign mesenchymal-type tumor was found and surgical excision was planned. Intraoperatively, a thymoma of the left cervical thymic tongue was found. At 6 months' follow-up, the ptosis and oral mucosal lesions had improved significantly, although she continued topical corticosteroid therapy intermittently for minor erosive oral disease. [source] Gastric emptying function changes in patients with thyroid cancer after withdrawal of thyroid hormone therapyJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2004PAN-FU KAO Abstract Background:, Hypothyroidism is commonly thought to cause decreased gastric emptying but is mostly associated with autoimmune disease. In the present study the gastric emptying function of thyroid cancer patients with severe hypothyroidism of short duration was evaluated with a radionuclide solid meal gastric emptying study. Methods:, Twenty-two patients who had undergone surgical operation and 131I ablation for thyroid cancer participated in solid meal gastric emptying studies before the withdrawal of thyroxine and then again 4 weeks after the withdrawal of thyroxine. Eleven patients had an additional gastric emptying study at 6 weeks after withdrawal of thyroxine. Gastric emptying curves and emptying parameters were calculated. Student's paired t -test was used for statistical analysis of data for all cases between the baseline and at 4 weeks after withdrawal. An additional repeated measure anova with multiple comparisons was performed on data between baseline, 4 weeks and 6 weeks after withdrawal for the other 11 patients. All P values presented are two-tailed and the significance level is 0.05. Results:, Hypothyroidism status was confirmed by the marked change of the serum thyroxine and thyroid-stimulating hormone 4 weeks and 6 weeks after withdrawal of the thyroxine replacement (P < 0.001). The gastric half-emptying time and emptying rate changed significantly after short-term severe thyroid hormone deficiency (P < 0.005). However, the length of the lag phase did not have a statistically significant change at 4 weeks or 6 weeks after withdrawal of the thyroxin replacement (P = 0.219 and 0.142). Conclusions:, Hypothyroidism following the withdrawal of the thyroxine replacement in thyroid cancer patients preparing for 131I cancer work-up can significantly prolong gastric half-emptying time and emptying rate. [source] Clinical and biochemical implications of low thyroid hormone levels (total and free forms) in euthyroid patients with chronic kidney diseaseJOURNAL OF INTERNAL MEDICINE, Issue 6 2007J. J. Carrero Abstract., Carrero JJ, Qureshi AR, Axelsson J, Yilmaz MI, Rehnmark S, Witt MR, Bárány P, Heimbürger O, Suliman ME, Alvestrand A, Lindholm B, Stenvinkel P (Karolinska Institutet, Stockholm; and Karo Bio AB, Novum, Huddinge; Sweden). Clinical and biochemical implications of low thyroid hormone levels (total and free forms) in euthyroid patients with chronic kidney disease. J Intern Med 2007; 262: 690,701. Objectives., In this study, we explore the associations of decreased thyroid hormone levels with inflammation, wasting and survival in biochemically euthyroid patients with end-stage renal disease (ESRD). Design., After exclusion of 23 patients with thyroid-stimulating hormone (TSH) values outside the normal range (0.1,4.5 mIU L,1), 187 clinically and biochemically euthyroid incident ESRD stage 5 patients starting dialysis were followed for a median of 20 (range 1,60) months. Measurements of total and free forms of thyroid hormones, s-albumin, hs-CRP, interleukin (IL)-6, vascular adhesion molecule (VCAM)-1 and insulin-like growth factor 1 (IGF-1) were performed at baseline. Results., In this population, 17 out of 210 patients (8%) were defined as subclinically hypothyroid. Multivariate analysis, according to receiver operating characteristic (ROC) curves, showed that mortality was best predicted by total triiodothyronine (T3). When using the cut-off levels derived from ROC, low T3 levels were associated with increased inflammation (higher hs-CRP, IL-6 and VCAM-1) and lower concentration of both s-albumin and IGF-1. Finally, low T3 but not low free triiodothyronine was associated with worse all-cause (Likelihood ratio = 45.4; P < 0.0001) and cardiovascular mortality (Likelihood ratio = 47.8; P < 0.0001) after adjustment for confounding factors. Conclusion., This study showed that low T3 levels are independent predictors of all-cause and also cardiovascular disease mortality in biochemically euthyroid patients, perhaps due to an intimate association with inflammation. Based on these results, the use of T3 levels in studies assessing the relationship between thyroid dysfunction and mortality risk is recommended. [source] Altered Thyroid Hormones and Behavioural Change in a Sub-Population of Rats Following Chronic Constriction InjuryJOURNAL OF NEUROENDOCRINOLOGY, Issue 8 2010E. Kilburn-Watt Hypothyroidism is associated with a disturbance of behaviour and mood. There are also individuals, not classified as hypothyroid, with low to ,low normal' thyroid hormone levels and normal thyroid-stimulating hormone (TSH) levels who have mood and behavioural changes. As the peripheral thyroid hormones decrease, TSH is expected to increase. However, there are a number of physiological mechanisms known to suppress TSH. In the present study, we report on thyroid hormone regulation in a rat model of neuropathic pain and altered social behaviour that is usually transient, but is persistent in a sub-group of the population. Following ligation of the sciatic nerve, male Sprague-Dawley rats were assessed for social dominance towards an intruder: 20% showed persistently decreased social dominance. Plasma levels of thyroid hormones, TSH and corticosterone were measured before and on days 2, 3, 4, 5 and 6 after injury in 21 rats. The mean plasma thyroxine (T4), free thyroxine (fT4) and triiodothyronine (T3) levels decreased significantly post-injury in rats with persistently changed behaviour compared to rats with unchanged behaviour (P , 0.002). There was no significant difference between groups for mean change in free triiodothyronine (fT3) or TSH. There was a correlation between decreased dominance behaviour and decrease in both T4 (r = 0.62, P = 0.009) and fT4 (r = 0.71, P = 0.001), but no correlation with TSH. In a sub-population of rats, decreased thyroid hormones did not result in the expected increased levels of TSH to restore pre-injury levels, nor did they show increased hypothalamic thyrotrophin-releasing hormone mRNA expression, indicating altered hypothalamic-pituitary-thyroid axis regulation. Because T3 availability to the brain is dependent on both circulating T3 and T4, decreased peripheral thyroid hormones may result in changed neural function, as expressed in altered complex behaviours in this sub-population of rats. [source] Palmoplantar pustulosis: a clinicoepidemiological study.JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2003The relationship between tobacco use, thyroid function ABSTRACT Background Palmoplantar pustulosis (PPP) is a skin disease characterized by chronically recurring sterile pustules on the palms and the soles. Although the aetiology of PPP is unknown, it is interesting to note the high prevalence of tobacco use in these patients. It would seem that there may be a relationship between PPP, autoimmune diseases and alterations of thyroid function. Methods We studied a total of 17 patients with ages ranging from 28 to 67 years, diagnosed with PPP. Patients were interviewed about: autoimmune diseases, psoriasis and thyroid disease, tobacco use (classified as: A, non-smoker; B, ex smoker; C, smoker of less than 20 cigarettes/day; D, smoker of more than 20 cigarettes/day). The patients were interviewed regarding the possible existence of a personal or family history of thyroid disease, determined using thyroid-stimulating hormone, thyroxine, antithyroid antibodies (antimicrosomal and antithyroglobulin antibodies). Results The majority of the patients smoked cigarettes (according to classification). Of the 12 patients for whom a thyroid study was performed three had been diagnosed with thyroid diseases, an increase in thyroid-stimulating hormone in one case and two showed an increase in antimicrosomial antibodies. Conclusions We have been able to demonstrate a high prevalence of thyroid dysfunction and tobacco use in patients with PPP. [source] Thyroid autoimmunity in children with features of both type 1 and type 2 diabetesPEDIATRIC DIABETES, Issue 4pt1 2008Ingrid M Libman Aim/hypothesis:, To assess the prevalence of autoimmune thyroid disease (ATD) in insulin-treated youth with clinical features of type 2 diabetes mellitus (T2DM). Methods:, We evaluated prevalence of thyroid peroxidase (TPO) and thyroglobulin (TGA) antibodies at onset of insulin-treated diabetes and follow-up in 183 White and Black children. Of these, 136 had a body mass index (BMI) <85th percentile with 122 (89%) positive for ,-cell autoimmunity [type 1 diabetes mellitus (T1DM)/group I], 25 were overweight (BMI ,85thpercentile) with or without acanthosis nigricans with ,-cell autoimmunity [,double' diabetes (DD)/group II], and 22 were overweight with no conventional ,-cell autoantibodies (group III). Results:, The prevalence of TPO and/or TGA was 39 and 29% (p = 0.19) in White and Black children and 39, 32, and 0% (p = 0.007) in groups I, II, and III, respectively. After a median follow-up of 60 months, 3.7, 4.3, and 0% developed hypothyroidism (increased thyroid-stimulating hormone with or without decreased free T4) in groups I, II, and III, respectively (p = 0.6). In subjects with TPO and/or TGA, hypothyroidism developed in 10 and 14% of groups I and II, respectively (p = 0.7). No child without thyroid antibodies developed hypothyroidism. Conclusions:, In patients with clinical features of T2DM who have evidence of ,-cell autoimmunity (DD), the frequency of thyroid antibodies and ATD is similar to that in classical T1DM. This suggests that TIDM comorbidities may be common in clinical T2DM patients who have ,-cell autoimmunity. Despite their obesity, youth with insulin-requiring diabetes should be screened for thyroid and possibly other T1DM-associated autoimmune diseases. [source] Cord blood thyroid-stimulating hormone and free T4 levels in Turkish neonates: Is iodine deficiency still a continuing problem?PEDIATRICS INTERNATIONAL, Issue 5 2010Fatih K Abstract Background:, The objectives of this study were to determine the cord blood thyroid-stimulating hormone (TSH) and free T4 (FT4) levels in Turkish neonates and to determine whether these variables reveal iodine deficiency. Methods:, We collected 818 cords from healthy mothers at parturition and measured levels of FT4 and TSH. We also measured cord blood FT4 and TSH levels in different stages of gestation and gender. We grouped the neonates according to cord serum TSH levels, either being less (Group A) or greater (Group B) than 10 mIU/L. Group A included 589 neonates (300 girls [51%] and 289 boys [49%]) and Group B included 229 neonates (105 girls [45%] and 124 boys [55%]). Results:, The percentage of subjects with cord blood TSH < 10 mIU/L and >10 mIU/L was 72% and 28%, respectively. Although cord TSH levels in Group B were greater than those in Group A (P < 0.001), cord blood FT4 levels in Group B were lower than those in Group A (P < 0.05). There was no difference between both sex in terms of birthweight and maternal age. TSH and FT4 levels did not vary according to neonate sex during gestation, except for from week 37 to 41. TSH levels of male neonates at the 41st week of gestation were higher than those of female neonates (P < 0.05). There were no effects of birthweight on TSH and FT4 levels if the neonate was lighter than 2500 g at birth. TSH levels of male neonates were higher than those of female neonates when their birthweights were <2500 g (P < 0.05). There was no significant difference in TSH levels according to birthweights in male neonates. Conclusion:, Our data provide the normative data for cord blood TSH and FT4 levels in Turkish neonates and show that iodine deficiency is a still a public health problem in Turkey. These measurements can be useful for detection and verification of hypothyroidism in a screening program for congenital hypothyroidism as well as evaluation of the success of the iodination program. [source] Thyroid function abnormalities among first-degree relatives of Iranian congenital hypothyroidism neonatesPEDIATRICS INTERNATIONAL, Issue 3 2010Mahin Hashemipour Abstract Background:, Congenital hypothyroidism (CH) is a relatively common metabolic disease in neonates. Until recent years the disorder was usually regarded as occurring in a sporadic manner. Over the past few years, however, a considerable proportion of familial cases have been identified, and possible roles of autoimmune factors suggested. The aim of the present study was to evaluate abnormality of thyroid function tests in first-degree relatives of CH neonates and compared this to the normal population. Methods:, From 2002 until 2007 thyroid function tests (T4 and thyroid-stimulating hormone [TSH]) were done in randomly selected CH and normal neonates (n= 194 and n= 350, respectively) and their first-degree relatives. Most mothers of the CH neonates and control groups were also evaluated for thyroid peroxidase antibody (TPOAb). Results:, Thyroid function test in first-degree relative of neonates with CH (361 parents, 136 siblings) were compared with those in control groups (665 parents, 478 siblings). Abnormal thyroid function tests were found in 85 patients in the CH group versus 96 patients in the control group; hypothyroidism was found in 75 (15.1%) and 57 subjects (5%) person in the CH and control groups, respectively (P < 0.05). Positive TPO antibody was found in 22 mothers (17.3%) of CH neonates in comparison with 65 mothers (32.5%) of control groups (P < 0.05). Frequency of hyperthyroidism in parents of control group had trend to be higher than parents of CH neonates (P= 0.05) Conclusion:, Familial and genetic components play a role in inheritance of CH, but maternal thyroid autoimmunity may not play an important role in the development of CH in Iran. [source] Incidence of iodine deficiency in Turkish patients with congenital hypothyroidismPEDIATRICS INTERNATIONAL, Issue 3 2008Olcay Evliyao Abstract Background: Turkey is located in an area of mild to moderate iodine deficiency. The aim of the present study was to investigate the incidence of iodine deficiency in patients with congenital hypothyroidism. Methods: Twenty five patients with a median age of 12 days (6 days,6 months) at diagnosis and followed for a median time of 7 months (1,60 months) were enrolled in the study. Thyroid function tests, thyroid scintigraphy, ultrasonography and urine iodine measurements of the patients and mothers were performed. Results and conclusion: Congenital hypothyroidism was diagnosed within postnatal day 13, between days 13 and 30, and after 30 days of age in 68%, 20% and 12% of the patients, respectively. At the time of diagnosis mean serum thyroid-stimulating hormone and total T4 were 85.3 ± 27.6 mIU/L and 3.9 ± 2.8 ,g/dL, respectively. Incidence of iodine deficiency was 36% in the patients (median, 110 ,g/L) and 88% in the mothers (median, 40 ,g/L). Thyroid scintigraphy and ultrasound were normal in all of the patients with iodine deficiency. At scintigraphic evaluation, thyroid gland was not visualized in 28% of patients; in the patients whose thyroid glands were not visualized scintigraphically thyroid ultrasonography indicated agenesis in 57%, and hypoplasia in 43%. In all the patients with thyroid agenesis or hypoplasia iodine levels were normal. In 36% of the patients imaging studies of thyroid gland and urine iodine measurements were normal. Despite salt iodization program, incidence of iodine deficiency is still high in patients with congenital hypothyroidism and mothers. National measures are urgently required for correction of iodine deficiency in Turkey. [source] Health-Related Quality-of-Life Study in Patients With Carcinoma of the Thyroid After Thyroxine Withdrawal for Whole Body ScanningTHE LARYNGOSCOPE, Issue 11 2006Sin-Ming Chow FRCR Abstract Objectives/Hypothesis: The authors studied the change of health-related quality of life (HR-QOL) in patients with differentiated thyroid carcinoma (DTC) with thyroxine (T4) withdrawal in preparation for whole body radioactive iodine scanning. Study Design: Seventy-eight patients with DTC and history of radioactive iodine (RAI) ablation were prospectively recruited. They completed the Functional Assessment of Cancer Treatment-General (FACT-G) questionnaire on weeks 0, 2, and 4 after T4 withdrawal with corresponding checking of serum thyroid-stimulating hormone (TSH). Results: Overall, 74.5% (58 of 78) of patients completed all FACT-G. Comparing FACT-G scores at weeks 0 and 4, "physical" (P < .001), "social" (P = .04), and "emotional" (P = .047) aspects were lowered as well as "total" HR-QOL (P = .001). However, the "functional" domain of HR-QOL was not affected (P = .14). Comparing FACT-G scores at week 0 and 2, we found that "physical" (P = .049) and "total" (P = .05) HR-QOL were affected early (in the first 2 weeks) in T4 withdrawal. Comparison of week 2 and 4 showed that in the later half of the withdrawal period, "physical" (P = .001), "emotional" (P = .02), and "total" FACT-G scores (P = .002) were affected. Mean TSH level (in mIU/L) increased gradually: 2.8 (week 0), 42.8 (week 2), 97 (week 3), and 153 (week 4). The percentage of patients attaining TSH level of >30 mIU/L were 55% (week 2), 96.2% (week 3), and 100% (week 4). Conclusions: HR-QOL declines with time of T4 withdrawal. The impact is more severe in the later period of T4 withdrawal. In 3 weeks, 96.2% of our patients attained TSH level of 30 mIU/L. To minimize the impact on HR-QOL, duration of T4 withdrawal can be decreased to 3 weeks. [source] Value of preoperative diagnostic modalities in patients with recurrent thyroid carcinomaBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2000A. Frilling Background The prognosis of differentiated thyroid carcinoma is usually excellent, but the majority of patients who develop a recurrence have a higher risk of death from the disease. Beside clinical examination, several diagnostic tools, such as ultrasonography, 131I scanning, [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) and thyroglobulin (TG) measurement under raised thyroid-stimulating hormone in serum can detect tumour recurrences. This prospective study compared the value of different diagnostic modalities in the detection of recurrent differentiated thyroid cancer. Methods From April 1992 to October 1999, 181 patients with thyroid carcinoma, of whom 150 had a well differentiated tumour, subjected to surgical treatment were identified prospectively. Some 107 patients (71 per cent) presented with primary tumour and 43 patients (29 per cent) with recurrent disease. The patients with tumour recurrence were evaluated regarding the mode of detection of recurrent disease, including clinical examination, ultrasonography, fine-needle biopsy (FNB), TG measurement and FDG-PET, the surgical treatment and outcome. Results Some 63 per cent of patients presented with regional lymph node metastases and 37 per cent with local recurrence. None of the patients with local recurrence was operated on for primary tumour in this department. In 87 per cent the recurrence was detected by clinical examination. Ultrasonography and 131I scan revealed suspicious findings in 97 and 69 per cent respectively. FNB disclosed abnormal cytological findings in 95 per cent. There were pathological TG levels in 86 per cent of patients. Among patients with a raised level of TG and negative scan results, 13 underwent FDG-PET, with pathological findings in 82 per cent. Conclusion In patients with well differentiated thyroid carcinoma, ultrasonography and FNB are the most sensitive methods for the detection of local recurrence or regional lymph node metastases. FDG-PET is a useful diagnostic tool in patients with a negative 131I scan and a raised level of TG. © 2000 British Journal of Surgery Society Ltd [source] Hypothyroidism in neonates post-iodinated contrast media: a systematic reviewACTA PAEDIATRICA, Issue 10 2009Alexandra Ahmet Abstract Aim:, To determine if neonates exposed to iodinated contrast media are at risk of hypothyroidism. Methods:, A systematic review was conducted by searching electronic databases (e.g. MEDLINE), contacting experts and scanning reference lists. Studies examining the effects of contrast media on neonatal thyroid function were included. Two reviewers independently screened the literature and assessed the risk of bias, while one reviewer abstracted data. Results:, Eleven studies were included; nine studies directly examined the risk of hypothyroidism (n = 182 neonates exposed to contrast media). All were highly affected by bias. In the three studies including term infants, one showed a trend towards increased thyroid-stimulating hormone (TSH) and decreased free thyroxine (FT4) among exposed groups. Six of 72 (8.3%) term infants exposed were treated for hypothyroidism. In studies of premature infants, there was a trend towards increased TSH (n = 3/7 studies), lower total thyroxine (n = 1), decreased triidothyronine and FT4 (n = 3) and hypothyroidism (n = 5). Twenty of 110 (18.2%) premature infants exposed were treated for hypothyroidism. Conclusion:, Hospitalized neonates exposed to iodinated contrast media are at risk for abnormal thyroid function and development of hypothyroidism. Premature infants might be at increased risk. Well-controlled studies are required to replicate our findings because the included studies were highly affected by bias. [source] Thyroid axis dysfunction in patients with Prader-Willi syndrome during the first 2 years of lifeCLINICAL ENDOCRINOLOGY, Issue 4 2010Elisa Vaiani Summary Introduction, Prader-Willi syndrome (PWS) is a genetic disorder caused by the loss of expression of paternally transcribed genes in a highly imprinted region of chromosome 15q11-13. The clinical phenotype has been well characterized, mostly related to hypothalamic dysfunction. Even though central hypothyroidism has been documented in 20,30% of patients with PWS, thyroid function during the first 2 years of life has not been clearly defined. Objective, To evaluate hypothalamic-pituitary-thyroid function in infant PWS patients. Study design, Eighteen patients with PWS, aged 0·16,2 years, were included in a prospective study. PWS diagnosis was based on clinical features and molecular analysis. Serum total (T) T4, free (F) T4, T3 and thyroid-stimulating hormone (TSH) were evaluated in the patients with PWS included in the study. Serum hormone values were compared to those of a large reference population of the same age. Results, In 13 of 18 patients with PWS (72·2%), serum TT4 and/or FT4 levels were below the 2·5th percentile of the reference population, while in only one PWS patient serum T3 was below this cut-off. Conclusion, The results of this study suggest that transient or definitive thyrotropin-releasing hormone (TRH)-TSH thyroid axis dysfunction may frequently be present in infant PWS patients. Paediatricians should be aware of this dysfunction in this critical period of thyroid hormone action on neurological development. [source] Effect of perinatal asphyxia on thyroid-stimulating hormone and thyroid hormone levelsACTA PAEDIATRICA, Issue 3 2003DN Pereira Aim: To compare serum concentrations of thyroid hormones,T4, T3, free T4 (FT4) and reverse T3 (rT3),and thyroid-stimulating hormone (TSH) found in the umbilical cord blood of term newborns with and without asphyxia and those found in their arterial blood collected between 18 and 24 h after birth. A further aim of the study was to assess the association between severity of hypoxic-ischemic encephalopathy and altered thyroid hormone and TSH levels, and between mortality and FT4 levels in the arterial blood of newborns between 18 and 24 h of life. Methods: A case-control study was carried out. The case group comprised 17 term newborns (Apgar score ,3 and ,5 at the first and fifth minutes; umbilical cord blood pH ,7.15) who required bag and mask ventilation for at least one minute immediately after birth. The control group consisted of 17 normal, term newborns (Apgar score ,8 and ,9 at the first and fifth minutes; umbilical cord blood pH ,7.2). Cord blood and arterial blood samples were collected immediately after birth and 18 to 24 h after birth, respectively, and were used in the blood gas analysis and to determine serum concentrations of T4, T3, FT4, rT3 and TSH by radioimmunoassay. All newborns were followed-up until hospital discharge or death. Results: Gestational age, birthweight, sex, size for gestational age, mode of delivery and skin color (white and non-white) were similar for both groups. No differences were found in mean levels of cord blood TSH, T4, T3 and FT4 between the groups. In the samples collected 18 to 24 h after birth, mean levels of TSH, T4, T3 and FT4 were significantly lower in the asphyxiated group than in the control group. Mean concentrations of arterial TSH, T4 and T3 between 18 and 24 h of life were lower than concentrations found in the cord blood analysis in asphyxiated newborns, but not in controls. In addition, asphyxiated newborns with moderate/severe hypoxic-ischemic encephalopathy presented significantly lower mean levels of TSH, T4, T3 and FT4 than those of controls. None of the asphyxiated newborns with FT4 ,2.0 ng/dl died; 6 out of the 11 asphyxiated newborns with FT4 < 2.0 ng/dl died. Conclusions: Serum concentrations of TSH, T4, T3 and FT4 are lower in asphyxiated newborns than in normal newborns between 18 and 24 h of life; this suggests central hypothyroidism secondary to asphyxia. Asphyxiated newborns with moderate/severe hypoxic-ischemic encephalopathy present a greater involvement of the thyroid function and consequently a greater risk of death. [source] | |||||||||||||||||||||||||||||||