Thyroid-stimulating Hormone Monitoring Research Articles

Analysis of options for prescribing hormone replacement therapy after thyroid organ-sparing surgery

Background. Performing thyroid organ-sparing surgery primarily aims to preserve the quality of life. Organ-sparing surgery should be understood as hemithyroidectomy with mandatory removal of the isthmus and pyramidal lobe of the thyroid (if present). The choice of one or another concept of prescribing hormone replacement therapy remains debatable. The purpose of the study is to determine the proportion of patients who do not need replacement therapy with levothyroxine after organ-sparing surgery on the thyroid gland, among those who were prescribed replacement therapy immediately and one month after discharge from the hospital, as well as to analyze the factors causing hypothyroidism in people with hemithyroidectomy. Materials and methods. The first group included 82 patients with hemithyroidectomy who were prescribed replacement therapy immediately after discharge from the hospital. The second group included 61 patients with hemithyroidectomy. The administration of replacement therapy was postponed for one month. A month after the operation, clinical examinations and monitoring of thyroid-stimulating hormone and free thyroxine indicators were performed. Results. After one month of observation, 72 (87.8%) of 82 patients in the first group continued to take levothyroxine, and 8 (13.1%) of 61 persons in the second group began to take it. In the first group, there was a moderate direct correlation between thyroid-stimulating hormone level before surgery and levothyroxine dose one month after (Spearman’s correlation coefficient 0.304, p=0.009). It was found that the chances of continuing taking levothyroxine after one month in the first group were 47 times higher than the chances of prescribing levothyroxine after one month in the second group. The proportion of patients in the first group who continued to take levothyroxine after one month was significantly higher than the proportion of patients in the second group who started taking levothyroxine after one month (87.8±3.6% vs. 13.1±3.5%, p<0.0001, Fisher’s exact test). Conclusions. Among patients who were prescribed hormone replacement therapy immediately after hemithyroidectomy, 12.2% did not need to continue taking levothyroxine after one month. Among persons in whom the administration of hormone replacement therapy was postponed for one month after hemithyroidectomy, 86.9% of patients did not require the use of levothyroxine in the future. The volume of the thyroid remnant ≤ 3.67 cm3 can be considered a predictor for hypothyroidism occurrence in the future, with a high risk of prescribing hormone replacement therapy. The study of such a factor as the ratio of the remnant thyroid volume to the body weight did not provide statistically reliable data for its use as a predictor of hypothyroidism occurrence in the postoperative period.

ODP445 If You Can't Beat Them, Join Them: A Therapeutic Strategy for Maintaining Euthyroidism in Non-Compliant Patients

Abstract Levothyroxine (LT4) has been the mainstay therapy for hypothyroidism since synthesized in 1949, and it was depicted to be a daily, usually lifelong, therapy. LT4 may have many interactions with other medications, food, and supplements, for which it should also be taken on an empty stomach, at least thirty minutes before consuming any other product, to achieve adequate absorption. These two characteristics of LT4 therapy are two of the main reasons for patient non-compliance, leading to uncontrolled hypothyroid state shown by abnormal thyroid stimulating hormone (TSH) levels, and associated symptoms. LT4 properties, such as seven-day half-life, as well as increased peripheral conversion to metabolically active T3 by local deiodinase enzyme when there are low T4 levels, provide a scenario where it can be used at longer dosing intervals than the traditional daily dosing. This is the case of a 27-year-old female with past medical history of hypothyroidism on daily replacement therapy with 50mcg of branded LT4, presenting to the endocrinologist for continuation of care. Over the course of visits, patient showed uncontrolled thyroid disease with altered levels of TSH, ranging from 5.4 uIU/mL up to 46.8 uIU/mL (N: 0.45-5. 0 uIU/mL), despite appropriate dose adjustments and frequent TSH and free T4 (FT4) monitoring. Due to persistent clinical and biochemical hypothyroidism requiring dosage increases up to 300mcg, patient was referred for a thyroxine absorption test to rule out LT4 malabsorption versus medication non-compliance. A supervised dose of 812mcg of the same branded LT4 was provided, based on body weight, and TSH, free T3, and free T4 levels were measured before administration and sequentially at 30, 45, 60, 90, 120, 240, and 360 minutes after dose, yielding TSH values ranging from 0.11 uIU/mL to 0.18 uIU/mL, consistent with adequate TSH suppression. Patient admitted to erratic medication ingestion for which a dose of 150 mcg LT4 orally daily was started. TSH levels remained above 9. 0 uIU/mL, for which a trial of complete weekly dosage was offered and accepted by patient. Two months after therapeutic adjustment, patient became both clinically and biochemically euthyroid, with TSH level of 1.35 uIU/mL without any adverse effects from excess hormone intake. Medication non-compliance is an issue every physician must battle with. This case serves as an example of the great impact of individualized modification of LT4 administration to establish a therapeutic regimen that adjusts to each patient's lifestyle while allowing them to remain clinically stable, which is a great benefit for both the patient and the clinician. Although studies already exist in proving the benefits of weekly versus daily therapy in such patients without major risks, further investigation should be conducted, as therapeutic guidelines could potentially change altogether in the future to avoid, or at least reduce, non-compliance consequences. Presentation: No date and time listed

Evaluation of Post-Hemithyroidectomy hypothyroidism

Objective: To evaluate the incidence of post-hemithyroidectomy hypothyroidism and identify possible risk factors that indicates which patients require thyroid function monitoring after surgery.
 Methods: A prospective study of patients with benign, non-toxic thyroid disease undergoing hemithyroidectomy between January 2017 and July 2019 in the Department of Otolaryngology and Head-Neck Surgery, Sir Salimullah Medical College Mitford Hospital, Dhaka. All patients were in euthyroid state preoperatively.Thyroid specimens were examined for pathological diagnosis and thyroid function was evaluated again six weeks after surgery.
 Results: All had normal preoperative thyroid function. Six weeks after surgery, 10 (22.22%) of the cases developed hypothyroidism (6.66% overt or symptomatic hypothyroidism and 15.56% subclinical hypothyroidism). The mean preoperative TSH level was significantly higher in the hypothyroid group than in the euthyroid group (2.1±1.1 vs 1.3±0.7mIU/L, p<0.01).Seven of patients with preoperative thyroid stimulating hormone (TSH) level more than or equal to 2 mIU/L developed hypothyroidism in comparison to only 3 of those with preoperative TSH <2 mIU/L (odds ratio 11.3).
 Conclusion: Ten (22.22%) patients in the present study developed hypothyroidism after hemithyroidectomy. Preoperative TSH more than or equal 2 mIU/L, elevation of thyroid antibodies and thyroiditiswarrant post-operative close TSH monitoring. Awareness of such risk factors for post-operative hypothyroidism would improve patients care and reduce complications.
 Bangladesh J Otorhinolaryngol; October 2020; 26(2): 95-101

Biochemical follow-up of nonfunctioning benign thyroid nodules.

For the biochemical follow-up of benign thyroid nodules, some authors recommend periodic lifelong measurement of thyroid-stimulating hormone (TSH) to assess for the development of toxic nodules over time. The purpose of this retrospective study was to assess the incidence of thyroid dysfunction over time in patients with benign thyroid nodule(s), with a normal TSH at diagnosis and to identify any factors that may predict biochemical dysfunction over time. Medical records of patients with the diagnosis of thyroid nodule(s) between January 2011 and August 2014 were reviewed. Patients who had TSH measurement within 1year of initial diagnostic ultrasound (US) were included. One-hundred fifty-seven patients identified with thyroid nodule(s) satisfied inclusion criteria. At a median follow-up of 45 (34-63) months, 13 (8.3%) patients developed thyroid dysfunction. The mean initial TSH in the group which developed subclinical hyperthyroidism (0.65mIU/mL) was statistically different from the group that did not develop thyroid dysfunction (1.37mIU/mL, P: 0.007). More patients with TSH <1mIU/L developed thyroid dysfunction as compared to subjects with TSH ≥1 mIU/L (P: .022). There was no significant difference in the incidence of thyroid dysfunction on the basis of gender, race, smoking status, TPO Ab positivity and number of nodules at diagnosis. We recommend re-examining the current practice and clinical utility of frequent TSH monitoring in all patients with thyroid nodules, particularly if initial TSH level is ≥1mIU/L.

Safety monitoring of treatment in bipolar disorder in a tertiary care setting in Sri Lanka and recommendations for improved monitoring in resource limited settings

BackgroundSafety monitoring of medicines is essential during therapy for bipolar disorder (BD). We determined the extent of safety monitoring performed according to the International Society for Bipolar Disorders (ISBD) guidelines in patients with BD attending the main tertiary care psychiatry clinics in Sri Lanka to give realistic recommendations for safety monitoring in resource limited settings.MethodsPatients diagnosed with BD on mood stabilizer medications for more than 1 year were recruited. Data were collected retrospectively from clinic and patient held records and compared with the standards of care recommended by ISBD guidelines for safety monitoring of medicines.ResultsOut of 256 patients diagnosed with BD, 164 (64.1%) were on lithium. Only 75 (45.7%) had serum lithium measurements done in the past 6 months and 96 (58.5%) had concentrations recorded at least once in the past year. Blood urea or creatinine was measured in the last 6 months only in 30 (18.3%). Serum electrolytes and thyroid-stimulating hormone (TSH) concentrations were measured in the last year only in 34 (20.7%) and 30 (18.3%) respectively. Calcium concentrations were not recorded in any patient. None of the patients on sodium valproate (n = 119) or carbamazepine (n = 6) had blood levels recorded to establish therapeutic concentrations. Atypical antipsychotics were prescribed for 151 (59%), but only 13 (8.6%) had lipid profiles and only 31 (20.5%) had blood glucose concentration measured annually. Comorbidities experienced by patients influenced monitoring more than the medicines used. Patients with diabetes, hypothyroidism and hypercholesterolemia were more likely to get monitored for fasting blood glucose and (p < 0.001), TSH (p < 0.001) and lipid profiles (p < 0.001). Lithium therapy was associated with TSH monitoring (p < 0.05). Therapy with atypical antipsychotics was not associated with fasting blood glucose or lipid profile monitoring (p > 0.05). A limitation of the study is that although some tests were performed, the results may not have been recorded.ConclusionsSafety monitoring in BD was suboptimal compared to the ISBD guidelines. ISBD standards are difficult to achieve in resource limited settings due to a multitude of reasons. Realistic monitoring benchmarks and recommendations are proposed for methods to improve monitoring in resource limited settings based on our experience.

Levothyroxine versus Levothyroxine with Iodine in Reduction of Thyroid Nodule Volume: A Double-Blind Randomized Controlled Trial

Objective: To compare levothyroxine alone and in combination with iodine on thyroid nodule volume reduction.&#x0D; Methods: &#x0D; Design: Double-Blind Randomized Controlled Trial&#x0D; Setting: Tertiary Government Hospital&#x0D; Participants: Nineteen (19) euthyroid patients age 19­-54 with at least 1 cytologically benign thyroid nodule were randomized to receive either levothyroxine + iodine or levothyroxine + placebo, taken once a day for 6 months with ultrasound and thyroid stimulating hormone monitoring on the 3rd and 6th month of intervention.&#x0D; Results: Main outcome measures included thyroid nodule volume reduction after six months of intervention. The mean change in volume from baseline to six months of levothyroxine + iodine group showed no statistically significant difference in nodule volume across time between levothyroxine + placebo group, -0.010 ± 1.250 (CI -0.521 - 0.501) versus 0.507 ± 1.128 (CI 0.025 - 0.990), p=.158. There were also new nodules (4 nodules) in the placebo group and none in the iodine group. No major adverse events were noted during the study.&#x0D; Conclusion: The two groups did not significantly differ in terms of nodule volume reduction.&#x0D; Keywords: thyroid nodule, prevention and control; drug therapy; iodine compounds, therapeutic use; levothyroxine, therapeutic use

Alternating Thyroid Status Between Thyrotoxicosis and Hypothyroidism in a Patient with Varying Antithyroid Antibodies

Autoimmune pathologies are a growing aspect of medicine. Knowledge about atypical cases is essential. This report will describe a case of unusual, alternating fluctuations in thyroid function. We report a case of thyrotoxicosis alternating with hypothyroidism in a 44-year-old, African-American woman and detail the clinical course and management. The patient presented in a mildly thyrotoxic state with features of thyroiditis that resolved soon thereafter. Subsequently, the course shifted toward a hypothyroid state with a thyroid-stimulating hormone (TSH) level of 24.53 μIU/ml (normal range is 0.45 to 4.5 μIU/ml; measured September 5, 2013) and free thyroxine (FT4) of 0.35 ng/dL (normal range is 0.5 to 1.40 ng/dL; measured September 5, 2013). It ensued with alternating hypothyroid and hyperthyroid trajectories for several cycles. Clinical management was adjusted to negotiate each progression. During certain intervals, levothyroxine was increased. At other visits, it was decreased. Periods without medication were observed as well. Furthermore, methimazole and metoprolol were utilized when required. Reversal of the condition occurred repeatedly. The entire course is tracked with over 30 instances of thyroid function measures that included hypothyroid, euthyroid (TSH at 1.54 μIU/mL, FT4 at 1.16 ng/dL) and thyrotoxic states (TSH at <0.005 μIU/mL, FT4 at 2.67 ng/dL). Various antibody titers were elevated including thyroid-stimulating immunoglobulin, thyroid peroxidase antibody, and TSH receptor antibody. Close monitoring of TSH and FT4 allowed for appropriate medication dose adjustment. This case highlights the unusual phenomenon of fluctuating thyroid function with autoimmune involvement of thyroid-stimulating immunoglobulin and TSH receptor antibodies. Close follow up aided responsive clinical management throughout the fluctuating clinical course.

Blood Lithium Monitoring Practices in a Population-Based Sample of Older Adults.

Lithium is an effective treatment for mood disorders, but lithium level and renal monitoring every 3 months is recommended in older patients treated with lithium to prevent serious adverse events. This study examined lithium monitoring practices in a large geriatric cohort. This population-based cohort study (N = 11,006) used linked health care administrative databases. Older lithium users (n = 5,503; mean age = 70.6 years) in Ontario, Canada, enrolled between April 1, 2002, and March 31, 2014, were propensity score matched 1:1 to valproate users (n = 5,503). The frequency with which serum lithium levels were monitored and renal and endocrine laboratory testing was done during a 1-year follow-up period was examined. The baseline characteristics of the 2 groups were similar. At least 1 serum lithium concentration recorded within 90, 180, and 365 days of follow-up was present in 24.1%, 42.4%, and 66.8% of lithium users, respectively. Corresponding numbers for serum creatinine were 29.6%, 50.4%, and 75.4%, respectively. While serum creatinine monitoring (hazard ratio [HR] = 1.19; 95% CI, 1.12-1.27; P < .001), thyroid-stimulating hormone monitoring (HR = 1.47; 95% CI, 1.37-1.58; P < .001), and calcium testing (HR = 1.15; 95% CI, 1.02-1.29; P = .018) were statistically higher in lithium compared to valproate users, absolute differences between groups were not clinically meaningful. In a geriatric Canadian community sample, lithium monitoring was infrequent and inconsistent with international standards that call for screening of lithium levels and renal function every 3 months.

Frequency of Thyroid-Stimulating Hormone Monitoring in Patients After Thyroidectomy: A Retrospective Study in Primary Care Practices in Germany.

The goal of this study was to analyze the frequency of thyroid-stimulating hormone (TSH) monitoring in thyroidectomy patients followed by general practitioners in Germany. This study included all individuals ≥18 years who had undergone a thyroidectomy between 2000 and 2015 in 258 general practices in Germany. Another inclusion criterion was a minimum of three medical visits between 2015 and 2016, following thyroidectomy. The primary outcome was the annual frequency of TSH monitoring in thyroidectomy patients in 2015. Demographic data included age, sex, and type of health insurance coverage (private versus statutory). Clinical and therapeutic data included the amount of time since the first thyroidectomy, thyroidectomy-associated diagnosis (thyroid cancer, noncancerous enlargement of the thyroid (goiter), or hyperthyroidism), type of thyroidectomy (total or hemithyroidectomy), the Charlson Comorbidity Index score, and the prescription of levothyroxine therapy in 2015. A multivariable logistic regression model was performed to identify variables potentially associated with the likelihood of having been tested at least once for TSH in the year 2015. The present study included 1,135 thyroidectomy patients. The mean age was 60.1 years (SD=14.3 years), and 75.8% of the patients were women. TSH was measured at least once in 42.3% of patients. In addition, 31.5% of individuals after thyroidectomy had mean TSH values between 0.25 and 1 mIU/L in 2015. No variable was significantly associated with the frequency of TSH monitoring. However, there was a tendency toward a lower TSH monitoring frequency in the groups which had undergone thyroidectomy years ago (OR=0.77 (95% CI: 0.53-1.11) for 1-5 years and OR=0.67 (95% CI: 0.45-0.99) for>5 years compared to<=1 year). Only 40% of thyroidectomy patients followed by general practitioners in Germany were monitored at least once for TSH in 2015.

Lymphocutaneous sporotrichosis treated with potassium iodide with development of subclinical hypothyroidism: wolff-chaikoff effect?

Sporotrichosis is a subcutaneous mycotic infection caused by Sporothrix schenckii that is acquired by traumatic implantation. The diagnosis is established by demonstration of fungal elements on histopathology and culture. Potassium iodide, azole antifungals, and terbinafine are the treatment options available. In this article, we report a 60-year-old female with lymphocutaneous sporotrichosis that responded well to potassium iodide. However, subclinical hypothyroidism (Wolff–Chaikoff effect) was encountered as a side effect of therapy which was managed with thyroxine replacement. Knowledge about the Wolff-Chaikoff effect (WCE) is important for the dermatologist and reinforces the need for screening and monitoring of thyroid stimulating hormone (TSH) in patients where long duration therapy is being planned.

Drug-Induced Hypothyroidism during Anti-Tuberculosis Treatment of Multidrug-Resistant Tuberculosis: Notes from the Field.

We followed 188 euthyroidic persons undergoing treatment for multidrug resistant tuberculosis (MDR-TB) in the state of Karnataka, India to determine the incidence of hypothyroidism during anti-tuberculosis treatment. Overall, among MDR-TB patients with valid thyroid stimulating hormone (TSH) values, about 23% developed hypothyroidism (TSH value ≥10 mIU/ml) during anti-tuberculosis treatment; the majority (74%) occurring after 3 months of treatment. Among 133 patients who received a regimen that contained ethionamide, 42 (32%) developed hypothyroidism. Among 17 patients that received a regimen that contained para-aminosalicylate sodium, 6 (35%) developed hypothyroidism. Among 9 HIV positive patients on anti-retroviral treatment, 4 (44%) developed hypothyroidism. These results differ from previously reported 4% incidence of hypothyroidism amongst patients who passively reported thyroidal symptoms during treatment, suggesting routine serologic monitoring of TSH throughout the course of treatment for MDR-TB is warranted.

Combination Of Lenalidomide, Dexamethasone and Cyclophosphamide as Treatment For The First Relapse Of Multiple Myeloma: Efficacy, Toxicity and Occurance Of Thyroid Abnormalities

BackgroundLenalidomide is immunomodulatory drug with a range of antineoplastic actions, it is highly effective in multiple myeloma (MM). Lenalidomide has been associated with various adverse side effects including fatigue, constipation, haematological and neurological toxicity. Thyroid dysfunction has been reported as a possible side effect of lenalidomide with incidence 5-10%. Symptoms of thyroid dysfunction can overlap with some side effects of lenalidomide. Thyroid hormone levels are not regularly evaluated in patients (pts) on lenalidomide. AimIn this report we have analysed a cohort of 73 MM pts treated with lenalidomide 25 mg daily (day 1-21, repeating of cycle on day +28) in combination with dexamethasone (160 mg or 320 mg per cycle) and cyclophosphamide 50 mg daily with aims to evaluate efficacy and adverse events of this treatment including of possible occurrance of thyroid impairment. MethodsWe have prospectively evaluated 73 pts with the first relapse of MM who received lenalidomide as a part of the second-line treatment between 2008 and 2012, median follow-up from start of treatment was 24 months (range 2-46), median age was 65 years. Median number of cycles was 6 (range 4-10). Thyroid function tests were checked in regular 2-month intervals from the start to the end of lenalidomide treatment - thyroid stimulating hormone (TSH) and free thyroxine (FT4). ResultsOverall response rate (ORR) was 53% (39/73), 10% (7/73) of pts were in complete remission (CR), very good partial response (VGPR) was achieved in 18% of pts (13/73), partial response (PR) in 25% of pts (19/73), minimal response (MR) or stable disease (SD) in 10% of pts (7/73), progression was observed in 37% of pts (27/73). Median time to progression (TTP) and overall survival (OS) from start of lenalidomide treatment were 18.4 and 29.6 months, respectively. Adverse events (AE) in time of lenalidomide treatment were frequent, but mostly grade 1 or 2. The most frequent AE were as follows: anemia (77%), neutropenia (67%), thrombocytopenia (54%), neuropathy (38%), fatigue (65%), infections (49%) and gastrointestinal toxicity (21%). Grade 3 or 4 adverse events included neuropathy (5%), thrombosis (4%), infections (15%), thrombocytopenia (10%), neutropenia (27%) and fatigue (6%). Previous diagnosis of thyroid dysfunction was presented in four MM pts (5%). New thyroid abnormalities grade 2 were developed on lenalidomide treatment in seven pts (10%). Hypothyreosis was presented in five pts, hyperthyreosis in two pts. Treatment of thyroid dysfunction was necesarry in all seven pts. Median time to occurrance of thyroid dysfunction was 4 months (range 2-8 months). ConclusionLenalidomide is effective treatment for the first relapse of MM with ORR 53%, but lenalidomide can cause various adverse events and significant thyroid abnormalities. Regular routine monitoring of TSH could be recommended in MM patients treated with lenalidomide. Treatment of symptomatic thyroid dysfunction can improve the quality of life for patiens undergoing lenalidomide treatment. Disclosures:No relevant conflicts of interest to declare.

Thyroxin overdose due to rheumatoid factor interferences in thyroid-stimulating hormone assays

Immunoassays are susceptible to interferences by anti-hormone antibodies, heterophilic antibodies or rheumatoid factor (RF). We report a case of levothyroxin overdose because of gross overestimation of thyroid-stimulating hormone (TSH) by chemiluminescent and IRMA assays. Alternate assays were performed and heterophilic antibodies blocking tubes were used. Analytical investigations revealed: i) non-linear concentrations of TSH after serum dilutions, ii) decreased TSH concentrations after removal of heterophilic antibodies, iii) appropriately decreased TSH concentrations in alternate TSH assays and iv) identification of increased concentrations of RF. The presence of RF may be responsible for false determination of TSH concentrations preventing monitoring of TSH.

Adherence to Amiodarone Monitoring Recommendations Before and After Implementation of a Centralized Pharmacy Service

The objective of this study was to determine whether patients enrolled in a centralized amiodarone monitoring service (AMS) were more adherent to amiodarone surveillance and whether the incidence of amiodarone-related toxicity differed for patients who were enrolled in the AMS. Amiodarone therapy was initiated in 917 patients in an integrated health care delivery system between October 1998 and December 2006. Electronic records were queried to establish the proportion of patients completing recommended amiodarone monitoring during the first year of therapy; specifically, thyroid stimulating hormone (TSH), alanine aminotransferase (ALT), electrocardiogram (ECG), and chest radiograph (CXR). Patients were assigned to the AMS or control cohort based on when amiodarone was initiated. Patients assigned to the AMS cohort were more likely to receive ALT monitoring at baseline, 6 months, and 1 year (68% vs 44%, P < .001; 86% vs 76%, P = .002; 84% vs 69%, P < .001; respectively) and ECG monitoring at baseline and 1 year (76% vs 58%; 96% vs 75%, P < .001, respectively). There was no difference in TSH monitoring at baseline, 6 months, and 1 year (55% vs 49%, P = not significant [NS]; 74% vs 70%, P = NS; 68% vs 64%, P = NS; respectively).

The upper limit of the reference range for thyroid-stimulating hormone should not be confused with a cut-off to define subclinical hypothyroidism

The upper limit of the reference range for serum thyroid-stimulating hormone (TSH) is used to assist in identifying individuals with hypothyroidism. Improvements in TSH assays have led to better definition of the lower limit of the reference range, but the upper limit of the range for a healthy population is currently a topic of some debate. Population studies have improved our understanding of the clinical implications of elevated serum TSH concentrations in terms of future progression to hypothyroidism, but have not yet fully elucidated the correlation of modestly elevated TSH levels with long-term morbidity. This paper will review the current debate including the arguments for and against reducing the upper limit of the TSH range, whether such a level should be based on evidence from epidemiological studies, and the implications of categorizing large numbers of people with subclinical hypothyroidism. The impact of using different methodologies for the measurement of TSH and the inherent variability of results on reference ranges is also discussed. We argue that the reference range for TSH should be assay-specific and be determined by standard techniques in normal populations as recommended by the National Academy of Clinical Biochemistry. In contrast, we suggest that a decision level be determined separately from epidemiological studies to identify a population with subclinical hypothyroidism. Serial monitoring of TSH in this population deserves further study as a means of identifying those at risk of progressing to frank hypothyroidism and meriting treatment.

Effects of long term iodized table salt consumption on serum T3, T4 and TSH in an iodine deficient area of Bangladesh

The effect of iodized and non-iodized table salt in goiter hyper-endemic area on the thyroid gland and its hormones T3, T4 and Thyroid Stimulating Hormone (TSH) were studied in two hundred subjects from the Center for Nuclear Medicine and Ultrasound, Mymensingh. Iodized and non-iodized salt users were called study and control groups respectively. The mean concentration of T3 were 2.38 nmol/L and 2.22 nmol/L & T4 concentration were 128.67 and 123.72 nmol/L in the study and control group respectively. The mean TSH concentration was 1.52 mIU/L and 1.62 mIU/L in study and control group. The data indicated that continuous and long term use of iodized salt increased both T3, T4 and decreased TSH in such a limit which was not statistically deferent at P< 0.05 level as compared to the control group. There was no significant change in occurrence of (hypo and hyper thyroidism or iodinated salt induced thyrotoxicosis) adverse effect, following iodine supplementation. The study shows that, mandatory mass iodination of table salt consumption in a hyper-endemic iodine deficient area is safe and does not cause any side effect. We suggest close regular monitoring of T3, T4, and TSH and further evaluation by specifically designed studies for any probable link between iodine induced hypo or hyperthyroidism and mass iodination of table salt consumption.

Hypothyroidism

<h2>Abstract</h2> Hypothyroidism is common, affecting 1–2% of women. The onset is often insidious and symptoms and signs are vague. It is essential to confirm the diagnosis biochemically before initiating treatment. Measurement of serum thyroid-stimulating hormone (TSH) is a highly sensitive and specific test for primary thyroid failure. Elevation of TSH with normal serum T4 is termed ‘subclinical' hypothyroidism. If free T4 is low, with raised serum TSH, the biochemical diagnosis is overt hypothyroidism. In the UK, hypothyroidism is usually autoimmune (characterized by positive antithyroid antibodies) or iatrogenic (secondary to treatment for hyperthyroidism). Worldwide, iodine deficiency remains a major cause. Overt hypothyroidism is treated with T4 replacement; the aim is to restore serum TSH and free T4 to the normal range and hence abolish relevant symptoms and signs. The starting T4 dose is 100 <i>µ</i>g/day, though lower doses should be used in those with a history of ischaemic heart disease. Serum TSH should be checked no sooner than 6–8 weeks after initiating T4, to prompt dose adjustment. The T4 dose required to restore biochemical euthryoidism is usually 100–125 <i>µ</i>g per day. Over-treatment with T4 (indicated by suppression of serum TSH) should be avoided, because of potential long-term risks. After euthyroidism has been restored, TSH should be checked annually to ensure ongoing compliance. There is little evidence that mild, subclinical hypothyroidism is associated with symptoms or adverse events, so if TSH is less than 10 mU/litre conservative management is reasonable, with annual monitoring of TSH to identify biochemical progression.

Soy Formula andthe Management of Congenital Hypothyroidism

Endocrinology| June 01 2004 Soy Formula andthe Management of Congenital Hypothyroidism AAP Grand Rounds (2004) 11 (6): 68–69. https://doi.org/10.1542/gr.11-6-68-a Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Soy Formula andthe Management of Congenital Hypothyroidism. AAP Grand Rounds June 2004; 11 (6): 68–69. https://doi.org/10.1542/gr.11-6-68-a Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search nav search search input Search input auto suggest search filter All PublicationsAll JournalsAAP Grand RoundsPediatricsHospital PediatricsPediatrics In ReviewNeoReviewsAAP NewsAll AAP Sites Search Advanced Search Topics: congenital hypothyroidism Source: Conrad SC, Chiu H, Silverman BL. Soy formula complicates management of congenital hypothyroidism. Arch Dis Child. 2004;89:37–40. Two case reports from 1995 and 1997 described children with congenital hypothyroidism and prolonged abnormal thyroid function tests while on soy formula.1,2 This retrospective study done at Northwestern Medical School in Chicago, Ill, was designed to evaluate the hypothesis that infants with congenital hypothyroidism who were fed soy formula have a prolonged thyroid-stimulating hormone (TSH) increase when compared to similarly affected infants who were fed a non-soy formula. The subjects were identified by their thyroid scan records, as these studies were performed on all patients at Children’s Memorial Hospital in Chicago suspected of having congenital hypothyroidism. Based on the dietary history recorded in the medical record, subjects were separated into either the soy or non-soy diet group, with the soy group consistently recorded as being on a soy formula throughout the first year of life. Ninety-nine patients with congenital hypothyroidism were identified between 1990 and 1998. Twenty-one children were excluded due to incomplete records or discontinuation of clinic visits before the age of 1 year. Of the remaining seventy-eight patients, 8 were in the soy diet group and 70 in the non-soy group. Seventy-one percent of the infants had thyroid dysgenesis and 17% had dyshormonogenesis. The levothyroxine dose used in both groups was comparable both initially and throughout the first year of life. Treatment in the soy group was started at 15 days and the non-soy group at 17 days. There was no difference in either the TSH or total thyroxine (T4) levels prior to treatment initiation. The first total T4 levels checked after the treatment initiation were similar in the 2 groups, but there was a marked difference in the first TSH measured after treatment was started. The soy diet group had a median TSH of 42.6 mU/l compared to 6.6 mU/l in the non-soy group. The first T4 and TSH were drawn at a median age of 50 days in both groups and the normalization of TSH was evaluated. The time that it took to achieve TSH of <10 mU/l differed, with the soy diet group taking a median of 150 days (range 54–229) compared to 40 days (19–189) in the non-soy diet group. At 4 months of age, 62.5% of the soy diet group continued to have increased TSH levels compared to 17% of the non-soy diet group, and this trend persisted throughout the first year of life. The authors concluded that infants with congential hypothyroidism who were fed a soy formula need close monitoring of free T4 and TSH and may require increased levothyroxine doses to achieve normal thyroid function tests. As normal development is critically dependent upon rapid normalization of thyroid function,3,4 the finding that ingestion of a soy formula is a possible barrier to achieving this goal has important implications. Although doses of levothyroxine of 7.4–9.3 μg/kg/day used to treat the... You do not currently have access to this content.

Assessment of hypothyroidism in patients with chronic heart failure.

To determine whether appropriate thyroid function measurements were being conducted in patients receiving care at a multidisciplinary heart failure clinic. Retrospective chart review. University-affiliated outpatient clinic. One hundred ninety-three patients with heart failure. Patients enrolled in the heart failure clinic at the Medical University of South Carolina from January 2000-April 2003 were identified. Their medical records were reviewed for demographics, New York Heart Association (NYHA) functional classification, laboratory data, and date of most recent heart failure clinic appointment. The records of 193 patients (43% women) were reviewed. Overall and subgroup analyses were performed based on patient characteristics such as presence of thyroid-stimulating hormone (TSH) level, interval since last heart failure clinic appointment, presence of thyroid replacement therapy, amiodarone use, NYHA functional class, and attending physician. Of the 193 patients, 77 (40%) had appropriate TSH monitoring, whereas 10 (32%) of 31 patients receiving amiodarone had appropriate monitoring. Forty-four (27%) patients not receiving amiodarone had no record of a TSH level. In 22 patients (11%), hypothyroidism was diagnosed and treated, whereas 16 patients (8%) had an abnormal TSH level but received no therapy. Forty percent of the 193 patients at this outpatient heart failure clinic received appropriate TSH monitoring. An opportunity exists for protocol implementation and education of pharmacists, nurse practitioners, and physicians concerning appropriate thyroid function monitoring in the heart failure population.