Differential Diagnosis Of Hyperthyroidism Research Articles

The role of color flow Doppler sonography study in differential diagnosis of thyrotoxicosis

Background: Thyrotoxicosis is a metabolic state of excessive thyroid hormones which include tetraiodothyronine (FT4) and/or triiodothyronine (FT3). The most common causes of thyrotoxicosis are either autoantibody-mediated hyperfunction of thyroid gland (Graves’ disease) or inflammation-induced destructive thyroiditis (subacute thyroiditis and postpartum thyroiditis). The correct diagnosis of thyrotoxicosis is important as management differs according to etiology. The radioactive iodine uptake test and technetium pertechnetate thyroid scan are the gold standard for diagnosis of thyrotoxicosis. However, these tests are limited by their availability and high cost. Therefore, it is important to look for other parameters which can help in the diagnosis of hyperthyroidism. The non-invasive thyroid color flow Doppler sonography (CFDS) is an easily available, highly informative, safe, and comparatively low-cost investigation which can be used as an alternative. Aims and Objectives: The aim of the study was to assess the role of CFDS in the differential diagnosis of thyrotoxicosis. Materials and Methods: A total number of 120 newly diagnosed thyrotoxic patients were enrolled. On the basis of clinical, laboratory evaluation, and thyroid scan, patients were diagnosed with either Graves’ disease or thyroiditis. All the patients underwent CFDS in the radiology department. Results: Ninety patients of Graves’ disease and thirty patients of thyroiditis were enrolled in our study. The mean peak systolic velocity (PSV) of inferior thyroid artery (ITA) from both lobes of thyroid gland were used as markers of thyroid vascularity. The difference in mean PSV-ITA in Graves’ and thyroiditis patients was statistically significant (P < 0.001). Using receiver operating characteristic analysis for diagnostic accuracy of PSV, we demonstrated that the cutoff 50 cm/s had 98.9% sensitivity and 96.7% specificity in differentiating Graves’ disease from thyroiditis with positive predictive value and negative predictive value being 99% and 96%, respectively. Conclusion: A non-invasive CFDS is an inexpensive and easily available procedure which provides the functional status of the thyroid gland. The PSV of ITA can help to differentiate the etiologies of thyrotoxicosis and can be considered as an alternative to nuclear scanning where such modality is not present or contraindicated.

Acute adrenal crisis precipitated by thyroid storm in a patient with undiagnosed autoimmune polyglandular syndrome type 2.

Autoimmune polyglandular syndrome (APS) type 2 is characterized by the presence of Addison's disease (AD) along with autoimmune thyroid disease and/or type 1 diabetes. APS type 2 is known as Schmidt's syndrome when autoimmune adrenal insufficiency is associated with chronic lymphocytic thyroiditis. We report a very rare case of a 28-year-old female patient who had Schmidt's syndrome revealed by a thyroid storm (TS) concomitant with an acute adrenal crisis. The onset of AD resulted in a surgical emergency. The patient presented with cardiogenic shock and an acute abdomen. The precipitation factor was Hashitoxicosis presented as TS. This life-threatening condition was successfully reversed with aggressive medical therapy based on antithyroid drugs and intravenous glucocorticoids. This hyperthyroid phase lasted for a period of 8 months. The patient eventually developed hypothyroidism, suggesting that Hashimoto's thyroiditis was the most likely diagnosis. She was started on levothyroxine replacement therapy and remained euthyroid on levothyroxine. The case we describe had several diagnostic pitfalls that are discussed both at the start as well as during the evolution. Autoimmune diseases can appear concomitantly or succeed each other over time. The clinician must be vigilant to detect these diseases in time in order to avoid a misdiagnosis of a life-threatening emergency such as adrenal insufficiency or thyroid storm. Thyroid storm is an uncommon but life-threatening manifestation of hyperthyroidism. Diagnosis is dependent on clinical symptoms, and no specific laboratory tests are available. Glucocorticoids should be used in the treatment of thyroid storm because they have an inhibitory effect on peripheral conversion of T4 to T3. In patients who have severe thyrotoxicosis, especially in conjunction with hypotension, treatment with glucocorticoids has become standard practice because of the possibility of relative adrenal insufficiency or the possibility of undiagnosed Addison's disease. The differential diagnosis of hyperthyroidism can be challenging. Graves' disease can be discussed in view of the severity of the clinical presentation and the prolonged duration of the hyperthyroid phase. Hashitoxicosis is the initial hyperthyroid phase in chronic autoimmune thyroiditis. The hyperthyroid phase is always followed by definitive resolution, with persistent euthyroidism and no hyperthyroid relapses. Synthetic antithyroid drugs may be prescribed during the hyperthyroid phase of Hashimoto thyroiditis if the clinical presentation is severe and the duration of the hyperthyroid phase is prolonged.

Research progress on differential diagnosis of thyrotoxicosis during pregnancy

Research progress on differential diagnosis of thyrotoxicosis during pregnancy

Differential Diagnosis of Thyrotoxicosis by Machine Learning Models with Laboratory Findings.

Differential diagnosis of thyrotoxicosis is essential because therapeutic approaches differ based on disease etiology. We aimed to perform differential diagnosis of thyrotoxicosis using machine learning algorithms with initial laboratory findings. This is a retrospective study through medical records. Patients who visited a single hospital for thyrotoxicosis from June 2016 to December 2021 were enrolled. In total, 230 subjects were analyzed: 124 (52.6%) patients had Graves’ disease, 65 (28.3%) suffered from painless thyroiditis, and 41 (17.8%) were diagnosed with subacute thyroiditis. In consideration that results for the thyroid autoantibody test cannot be immediately confirmed, two different models were devised: Model 1 included triiodothyronine (T3), free thyroxine (FT4), T3 to FT4 ratio, erythrocyte sediment rate, and C-reactive protein (CRP); and Model 2 included all Model 1 variables as well as thyroid autoantibody test results, including thyrotropin binding inhibitory immunoglobulin (TBII), thyroid-stimulating immunoglobulin, anti-thyroid peroxidase antibody, and anti-thyroglobulin antibody (TgAb). Differential diagnosis accuracy was calculated using seven machine learning algorithms. In the initial blood test, Graves’ disease was characterized by increased thyroid hormone levels and subacute thyroiditis showing elevated inflammatory markers. The diagnostic accuracy of Model 1 was 65–70%, and Model 2 accuracy was 78–90%. The random forest model had the highest classification accuracy. The significant variables were CRP and T3 in Model 1 and TBII, CRP, and TgAb in Model 2. We suggest monitoring the initial T3 and CRP levels with subsequent confirmation of TBII and TgAb in the differential diagnosis of thyrotoxicosis.

FT3 index/TSH index ratio and free thyroid hormone index in the differential diagnosis of thyrotoxicosis

Aim: Common causes of thyrotoxicosis are hyperthyroidism and destructive thyroiditis. Hyperthyroidism is a condition characterized by high serum thyroid hormone levels as a result of over-synthesis of thyroid hormones, the most common causes of which are Graves' disease (GD) and toxic nodular goiter (TNG). Subacute thyroiditis (SAT) causes thyrotoxicosis due to the circulating thyroid hormones of destructive thyroiditis. Differential diagnosis is important because GD, TNG and SAT treatment approaches are different. The aim of this study was to analyze whether it is possible to make a differential diagnosis for these conditions by examining free thyroid hormones, fT3/fT4 ratio, fT3 index/TSH index (fT3I/TSHI) ratio and Free Thyroid Hormone Index (FTHI).
 Material and Method: This retrospective study included 150 patients who were diagnosed with GD, TNG and SAT. The fT3 index (fT3I) was calculated as the ratio between the fT3 value and the fT3 upper limit of normal value (fT3I=fT3/4 pg/ml). The fT4 index (fT4I) was calculated as the ratio between the fT4 value and the fT4 upper limit of normal value (fT4I=fT4/1.23 mg/dl). The TSH index (TSHI) was calculated as the ratio between TSH value and the TSH lower limit of normal limit (TSHI=TSH/0.38 mIU/L). The FTHI index was calculated using the formula of (fT3 level/fT3 upper limit of normal) / (fT4 level/fT4 upper limit of normal).
 Results: The fT3, fT3/fT4 ratio and FTHI were found to be higher in hyperthyroid patients compared to subacute thyroiditis patients. fT4 and fT3I/TSHI levels were similar in hyperthyroid patients and SAT patients (p=0.49, p=0.11, respectively ). The cut-off level of FTHI for hyperthyroidism was determined as 0.97 with sensitivity of 75% and specificity of 76.3% (AUC=0.833, p< 0.001). When hyperthyroidic patients were divided into two groups as GD and TNG, no significant difference was found in fT3/fT4 ratio (p:0.99). The fT3 (p

Utility of TSH Receptor Antibodies in the Differential Diagnosis of Hyperthyroidism in Clinical Practice.

Graves’ disease (GD) is the most common cause of hyperthyroidism in iodine-sufficient areas. It is important to distinguish GD from other causes of hyperthyroidism for optimal management. Thyroid stimulating hormone receptor antibody (TRAb) test is a commonly used test for this purpose. However, the sensitivity for this test in routine clinical practice may be affected by various factors leading to fallacies in diagnosis.Materials and Methods:A retrospective study was performed to assess the utility of an automated electrochemiluminescence TRAb immunoassay (Roche) in differentiating GD from non-Graves’ disease (NGD) in routine clinical practice.Results:In 227 subjects, 146 had GD and 81 had NGD. Total T3, Total T4, Free T4, and TRAb were significantly higher in people with GD in comparison to NGD. The area under the receiver operating characteristics (ROC) curve for the assay was 0.96 (95% CI: 0.926 to 0.984, P < 0.0001). The optimal threshold for the test derived from the ROC was 3.37 IU/L, which is more than the cut-off of 1.75 IU/L suggested by the manufacturer. The sensitivity/specificity of TRAb in the diagnosis of GD at presentation was 98.4%/62.9% at 1.75 IU/L and 91.2%/90.12% at 3.37 IU/L, respectively.Conclusion:The TRAb test is a sensitive test to differentiate between subjects with GD and NGD presenting with hyperthyroidism. However, the cutoff (1.75 IU/L) as per the kit manufacturer may lead to a lower specificity for diagnosis. A modified cut-off of 3.37 IU/L should be considered for optimizing the diagnostic efficacy of the test.

Graves hastalığının nadir bir prezentasyonu: bilateral gode bırakan bacak ödemi

Graves’ disease has many extrathyroidal manifestations. In the literature, bilateral pretibial pitting edema in hyperthyroidism cases has been reported in a few case reports. In the current presentation, we report a case of Graves who had leg and hand swelling for two weeks and whose findings regressed rapidly with treatment. Diffuse, bilateral pitting pretibial edema, which may occur due to many etiologies, should also be considered in the differential diagnosis of hyperthyroidism.

Difficulties in differential diagnosis of thyrotoxicosis: case report

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Gestational Thyrotoxicosis in a Patient With Hyperemesis Gravidarum

Untreated or inadequately treated overt hyperthyroidism in pregnancy can have devastating consequences for both mother and fetus. At the same time antithyroid drugs (ATDs) are known for their teratogenic effect and should be avoid when possible; once the diagnosis of hyperthyroidism is made in a pregnant woman, attention should be focused on determining the etiology of the disorder and whether it warrants treatment. Here, we report a case of hyperemesis gravidarum patient presenting with significant elevation of thyroid hormones and a review on diagnosis and management of gestational transient thyrotoxicosis. A 33-year-old female, G4P3 at 8 weeks pregnant admitted for nausea and vomiting. Thyroid labs showed TSH < 0.01 (Reference: 0.4-4.0mU/L) and free T4 is 3.53 (Reference: 0.76-1.46ng/dl). Patient was discharged on antiemetics with a diagnosis of hyperemesis gravidarum. She was re-admitted at 9 weeks pregnant with ongoing nausea and vomiting. She had palpitations, fatigue and reported 15 pound weight loss in 2 weeks. Past medical history included thyroid hormone abnormality noted during pregnancies of 2011 and 2017. Physical exam was significant for tachycardia and diffusely enlarged thyroid gland. Repeat labs showed TSH <0.01, free T4 5.81, total T3 of 317 (Reference: 60-181ng/dl). Thyroid ultrasound showed multiple nodules. Considering significant elevation in free T4 and total T3; empiric therapy with propylthiouracil was recommended. Patient declined anti-thyroid therapy. TSI and TRH antibodies came back later as negative. Patient was treated with enteral feeding for hyperemesis gravidarum. Thyroid labs 3 weeks later improved; FT4 down to 1.63 and TT3 down to 250. Patient delivered healthy baby at 40 weeks of gestation. Although the differential diagnosis of thyrotoxicosis in pregnancy includes any cause that can be seen in a nonpregnant patient, the most likely causes for hyperthyroidism in pregnancy are gestational thyrotoxicosis (GTT) with or without hyperemesis gravidarum or Graves’ disease. GTT is described as an hCG-mediated hyperthyroidism that occurs in the first trimester of pregnancy; it is generally asymptomatic with mild biochemical hyperthyroidism. Distinguishing true overt hyperthyroidism from GTT in a setting of hyperemesis gravidarum is challenging. The absence of clinical signs of hyperthyroidism and negative thyroid antibodies supports the diagnosis of GTT. T3 tends to be disproportionately elevated more than T4 in patients with overt hyperthyroidism. HCG level has not been found to be useful in distinguishing between GTT and GD. Overt hyperthyroidism is treated using anti-thyroid drugs (ATD) whereas supportive therapy without ATD is the accepted standard of treatment of patients with hyperemesis gravidarum and GTT. More studies addressing the best management of these group of patients is needed.

Difficulties in Differential Diagnosis of Thyrotoxicosis: Clinical Case

Introduction: Thyrotoxicosis (T) develops as a result of persistent excess of thyroid hormones (TH). There are two groups of diseases that are fundamentally different in pathogenesis. The first group includes those in which the production of TH increases. Diseases of the second group are accompanied by T caused by destruction of the thyroid gland tissue. Therapeutic approaches for different pathogenetic types of T are different, therefore, a careful differential diagnosis of T is necessary, even if at first glance the diagnosis seems obvious. Clinical Case: A 35-year-old patient consulted a physician complaining of weakness, weight loss by 11 kg in 1.5 months, tremors, palpitations, which first appeared about a month ago. The examination revealed TSH <0.0083 mU/l (0.4-4.0), and an endocrinologist’s consultation was recommended. On examination, the thyroid gland is no larger than the distal phalanx of the subject’s thumb, BMI=24 kg/m2, HR=100 bpm, BP=115/80 mm Hg. Laboratory examination: TSH <0.0083 mU/l, free T4 =28.29 pmol/l (9.0-19.05). Ultrasound of the thyroid gland: signs of diffuse changes in tissue, the total volume=16.8 ml3. For differential diagnosis of T, antibodies to TSH receptors were determined, the titer of which turned out to be slightly increased 1.43 IU / L (<1). A diagnosis of Graves’ disease (GD) was made and treatment was prescribed (Tyrozol 30 mg, Bisoprolol 2.5 mg per day). After 3 weeks, the patient noted an improvement in well-being, but weakness, tremor, an increase in free T4 (23.33 pmol/l) and total T3 (3.26nmol / l at a rate of 0.98-2.33) remained. The lack of achievement of the target values of TH levels was regarded as inadequacy of the received dose of Tyrozol, in connection with which it was decided to increase the dose to 40 mg per day. After 2 weeks, an increase in free T4 (27.26 pmol/L) and total T3 (3.84 nmol/L) remained. The lack of positive dynamics called into question the diagnosis of GD. With a more thorough collection of anamnesis, it was found that 1.5 years ago, the patient took amiodarone for 6 months as prescribed by a cardiologist (he does not remember the dose). In this connection, to establish the cause of T, scintigraphy was performed: revealed a weak accumulation of a radiopharmaceutical with diffuse uneven distribution. Based on the data obtained, amiodarone-induced T type 2 was verified. Treatment was corrected: Tyrosol withdrawal and Prednisolone administration, 40 mg/day with positive dynamics from treatment. Conclusion: Clinical case demonstrates how important it is to carefully collect the patient’s history and follow the algorithms for differential diagnosis. Errors in diagnosis lead to incorrectly prescribed treatment, lengthening the duration of symptoms, which affects not only the patient’s quality of life, but also reduces the level of his trust in medical professionals.

Serum thyroglobulin level in newly detected thyrotoxicosis and its role in differential diagnosis of thyrotoxicosis

Background: Elevated serum thyroglobulin (Tg) level is commonly observed in various forms of thyrotoxicosis; the levels vary according to different etiologies. This study aimed at identifying the value of serum Tg level in the differential diagnosis of common etiologies of thyrotoxicosis. Methods: This cross-sectional study was conducted at the endocrine outpatient department of a tertiary hospital in Bangladesh from March 2015 to May 2017. In this study, 200 subjects with newly detected untreated thyrotoxicosis were evaluated. Serum Tg was assayed by chemiluminescent immunometric assay. Results: Serum Tg level was raised in 48% of subjects. Subjects aged ≥40 years, and those having a family history of thyroid disorders had relatively higher thyroglobulin levels. The frequency of subjects with an elevated Tg was highest in subacute thyroiditis (89.5%) followed by toxic nodular goiter (77.3%) and Graves’ disease (32.9%); the difference in the frequencies was statistically significant (p&lt;0.001). Median Tg was highest in the subjects with subacute thyroiditis (132.6 ng/ml) followed by toxic nodular goiter (99.55 ng/ml); those with Graves’ disease had the lowest Tg level (12.5 ng/ml); the differences in median Tg levels across the three groups were also statistically significant (p&lt;0.001). Conclusions: Serum thyroglobulin level may be useful for the etiological diagnosis of thyrotoxicosis.

Free triiodothyronine to free thyroxine ratio in the differential diagnosis of thyrotoxicosis and hyperthyroidism: A retrospective study.

Thyroid ultrasound, thyroid scintigraphy and radioactive iodine uptake (RAIU) tests are helpful in the differential diagnosis of thyrotoxicosis and hyperthyroidism. In the setting where these techniques are unavailable or unusable more accessible, and cheaper techniques would be helpful. We evaluated the capability of free triiodothyronine to free thyroxine ratio (FT3/FT4) to differentiate Graves' Disease (GD) and destructive thyroiditis (DT). In total, 318 patients with GD and 140 patients with DT were included in the study. Patients were assigned to two groups: GD and DT (subacute thyroiditis, painless thyroiditis, postpartum thyroiditis). Serum thyroid-stimulating hormone (TSH), FT4, FT3 levels and FT3/FT4 ratio were evaluated in each group. To obtain the optimal diagnostic cut-off value of FT3, FT4 and FT3/FT4 ratio, ROC curve analysis was performed of all untreated thyrotoxicosis patients. The optimal FT3/FT4 ratio cut-off value was 2.96, with a sensitivity of 71.7%, the specificity of 88.6%. The area under the ROC curve of the FT3/FT4 ratio regarding the diagnosis of GD was 0.864 (95% CI: 0.830-0.894). The cut-off level of FT3 for GD was determined as 6.6pg/mL which had a sensitivity of 72.3% and specificity of 68.6% (AUC=0.771 P<.001). The cut-off level of FT4 for GD was determined as 3.65ng/dl with a sensitivity of 35.5% and specificity of 83.6% (AUC=0.615 P<.001). When a high specificity is needed, FT3/FT4 cut-off value increases to 3.63 with 99.3% specificity and 36.5% sensitivity. FT3/FT4 ratio helps distinguish GD and DT. In cases of situations where RAIU/scintigraphy and TRAb cannot be studied, the FT3/FT4 ratio is a viable diagnostic tool. Cut-off values with higher specificity can be more helpful in differential diagnosis of GD.

Serum Ratio of Free Triiodothyronine to Thyroid-Stimulating Hormone: A Novel Index for Distinguishing Graves' Disease From Autoimmune Thyroiditis.

ObjectiveGraves’ disease (GD) and autoimmune thyroiditis (AIT) are two major causes of thyrotoxicosis that require correct diagnosis to plan appropriate treatment. The objectives of this study were to evaluate the usefulness of thyroid-related parameters for distinguishing GD from AIT and identify a novel index for differential diagnosis of thyrotoxicosis.DesignThis retrospective study was performed using electronic medical records in Peking University People’s Hospital (Beijing, China).MethodsIn total, 650 patients with GD and 155 patients with AIT from December 2015 to October 2019 were included in cohort 1. Furthermore, 133 patients with GD and 14 patients with AIT from December 2019 to August 2020 were included in cohort 2 for validation of the novel index identified in cohort 1. All patients were of Chinese ethnicity and were newly diagnosed with either GD or AIT. Thyroid-related clinical information was collected before intervention by reviewing the patients’ electronic medical records. Receiver operating characteristic curve analysis was used to identify the optimal cutoff for distinguishing GD from AIT.ResultsIn cohort 1, thyroid-stimulating hormone (TSH) receptor antibody was identified as the best indicator for distinguishing GD from AIT. The area under the receiver operating characteristic curve was 0.99(95% confidence interval: 0.98–0.99, p<0.0001)and the optimal cutoff was 0.84 IU/l (98% sensitivity and 99% specificity). The free triiodothyronine (FT3)/TSH ratio (FT3/TSH) was the second –best for distinguishing GD from AIT, the area under the receiver operating characteristic curve of FT3/TSH was 0.86 (95% confidence interval: 0.84–0.88, p<0.0001); its optimal cutoff was 1.99 pmol/mIU (79% sensitivity and 80% specificity). Its effectiveness was confirmed in cohort 2 (81% sensitivity and 100% specificity).ConclusionsThe FT3/TSH ratio is a new useful index for differential diagnosis of thyrotoxicosis, especially when combined with TRAb.

Management of Graves Thyroidal and Extrathyroidal Disease: An Update

ContextInvited update on the management of systemic autoimmune Graves disease (GD) and associated Graves orbitopathy (GO).Evidence acquisitionGuidelines, pertinent original articles, systemic reviews, and meta-analyses.Evidence synthesisThyrotropin receptor antibodies (TSH-R-Abs), foremost the stimulatory TSH-R-Abs, are a specific biomarker for GD. Their measurement assists in the differential diagnosis of hyperthyroidism and offers accurate and rapid diagnosis of GD. Thyroid ultrasound is a sensitive imaging tool for GD. Worldwide, thionamides are the favored treatment (12-18 months) of newly diagnosed GD, with methimazole (MMI) as the preferred drug. Patients with persistently high TSH-R-Abs and/or persistent hyperthyroidism at 18 months, or with a relapse after completing a course of MMI, can opt for a definitive therapy with radioactive iodine (RAI) or total thyroidectomy (TX). Continued long-term, low-dose MMI administration is a valuable and safe alternative. Patient choice, both at initial presentation of GD and at recurrence, should be emphasized. Propylthiouracil is preferred to MMI during the first trimester of pregnancy. TX is best performed by a high-volume thyroid surgeon. RAI should be avoided in GD patients with active GO, especially in smokers. Recently, a promising therapy with an anti-insulin-like growth factor-1 monoclonal antibody for patients with active/severe GO was approved by the Food and Drug Administration. COVID-19 infection is a risk factor for poorly controlled hyperthyroidism, which contributes to the infection–related mortality risk. If GO is not severe, systemic steroid treatment should be postponed during COVID-19 while local treatment and preventive measures are offered.ConclusionsA clear trend towards serological diagnosis and medical treatment of GD has emerged.

Evaluation of the role of thyroid scintigraphy in the differential diagnosis of thyrotoxicosis.

A differential diagnosis of thyrotoxicosis is crucial as the treatment of the main causes of this condition can vary significantly. Recently published diagnostic guidelines on thyrotoxicosis embrace the presence of thyrotropin receptor (TSH-R) antibodies (TRAb) as the primary and most important diagnostic step. The application of diagnostic algorithms to aid in the treatment of hyperthyroidism supports using thyroid radionuclide scintigraphy (TRSt) in baffling clinical scenarios, when TRAb are absent or when third-generation TRAb are not available. First-generation TRAb measurement may have limitations. Consequently, patients with thyrotoxicosis and first-generation TRAb results may be misdiagnosed and consequently improperly treated. Our purpose was to compare first-generation TRAb values to TRSt in the differential diagnosis of hyperthyroidism. We conducted a retrospective study of 201 untreated outpatients with overt or subclinical hyperthyroidism on whom first-generation TRAb and TRSt had been performed at the time of diagnosis. Histological specimens were analysed in patients who had previously undergone thyroid surgery at our centre. SPSS 20.0 was used in statistical analysis. Seventy-three out of 201 (36.3%) patients had positive TRAb. A diffuse uptake was present in 83.5% (61/73), whereas 13.7% (10/73) had a heterogeneous uptake and 2.7% (2/73) had an absent uptake. Thirty out of 91 (33%) patients with diffuse uptake were negative for positive TRAb and were diagnosed with Graves' disease. Analysis of 37 histological specimens indicated that TRSt had greater accuracy (81% vs 75.7%) and specificity (79.2% vs 57.1%) when compared to TRAb in the differential diagnosis of thyrotoxicosis. However, TRSt sensitivity was inferior to TRAb (84.6% vs 92.3%). Our study endorses that initial differential diagnosis of thyrotoxicosis should not be based solely on first-generation TRAb as this approach may leave nearly 20% of the patients misdiagnosed and, consequently, improperly treated. Our results underscore that thyroid scintigraphy should also be performed when only first-generation TRAb assays are available during the initial differential diagnosis of thyrotoxicosis.

Do Superior Thyroidal Artery Doppler Findings Play a Role in the Differential Diagnosis of Hyperthyroidism?

Amac: Hipertiroidinin erken tani ve dogru tedavisi, iliskili sistemik komplikasyonlari onleyebilmek acisindan onemlidir. Ayirici tanida serum tiroid hormonlari, tiroid otoantikorlari ve radyoaktif iyot uptake sintigrafisi kullanilmakta ancak bu incelemelerle kesin taniya gidilememektedir. Calismamizda laboratuar bulgularinin yaninda superior tiroidal arterin dublex doppler ultrason bulgularinin taniya katkisini degerlendirdik. Bu doppler bulgularinin, gri scala ultrasonografi bulgularina ek destekleyici bir yontem olabilecegini gostermeyi amacladik. Araclar ve Yontem: Calismaya 75’i kadin ve 21’i erkek olmak uzere toplam 96 kisi dahil edildi. Hipertiroidili gruplar graves hastaligi (GD) ve toksik multinoduler guatri olan (TMNG); sirasiyla 29 ve 41 kisiydi. Kontrol grubu olarak calismaya otiroid 26 kisi dahil edildi. Tum bireylere yapilan dublex doppler ultrason ile superior tiroidal arterlerinin pik sistolik hiz, end diastolik hiz ve rezistivite index degerlerine bakildi. Pik sistolik degerlerinin toksik multinoduler guatr grubunda gravefs hastalarina gore anlamli yuksek oldugu bulundu. Bulgular: TMNG and GD hastalarinda, pik sistolik hiz, diyastol sonu hiz ve rezistif index degerleri kontrol grubuna gore anlamli yuksek bulundu (p<0.001). TMNG ve GD hastalari karsilastirildiginda ise sadece pik sistolik hiz degeri TMNG’li grup lehine anlamli yuksek bulundu. TMNG‘li grubun ( 50.5±26.5 cm/sec) ve GD’li (34.2±11.5 cm/sec) grubun pik sistoli hiz degerleri klinik tani aninda karsilastirildi. Sonuc: Hipertiroidi ayirici tanisinda sintigrafinin gerekli oldugu yerlerde superior tiroidal arterin pik sistolik hiz degerlerinin kullanilabilecegi kanaatindeyiz. Boylece alinabilecek potansiyel radyasyon dozu ve kaybedilecek zaman onlenebilir.

Painless destructive thyroiditis in a patient with resistance to thyroid hormone: a case report

BackgroundResistance to thyroid hormone (RTH) usually features a syndrome of inappropriate secretion of thyroid-stimulating hormone (SITSH) without suppression of the typical high thyroid hormone levels. However, some patients with RTH show thyroid-stimulating hormone (TSH) suppression due to thyrotoxicosis. We report a case of painless thyroiditis in a patient with RTH that was misdiagnosed as Graves’ disease because of TSH-suppressed thyrotoxicosis.Case presentationA sixteen-year-old boy consulted a local general physician for fatigue. He had a goiter, and biochemical analysis showed TSH < 0.1 μIU/mL, free triiodothyronine (FT3) of 2.70 pg/mL, and free thyroxine (FT4) of 3.6 ng/dL. He was diagnosed with Graves’ disease and was treated with 20 mg thiamazole. One year later, he was referred to the department of endocrinology because of SITSH. He was finally diagnosed with RTH due to the finding of a heterozygous missense mutation (methionine 334 threonine) in the thyroid hormone receptor β gene. Three years after cessation of thiamazole, his hyperthyroxinemia showed marked exacerbation with TSH suppression. We diagnosed him with painless destructive thyroiditis because of low technetium-99 m (Tc-99 m) uptake in the thyroid. Extreme hyperthyroxinemia was ameliorated, with a return to the usual SITSH levels, within 1 month without any treatment.ConclusionThe present case demonstrates that diagnosing RTH is difficult when patients show hyperthyroxinemia with complete suppression of TSH to undetectable levels, and the data lead to misdiagnosis of RTH as Graves’ disease. The initial diagnosis is important, and Tc-99 m scintigraphy is useful for the differential diagnosis of thyrotoxicosis accompanying RTH.

Differential Diagnosis of Thyrotoxicosis

Hyperthyroidism is characterized by increased thyroid hormone synthesis and secretion from the thyroid gland, whereas thyrotoxicosis refers to the clinical syndrome of excess circulating thyroid hormones, irrespective of the source. Thyrotoxicosis is characterized by low serum thyroid-stimulating hormone (TSH) level and elevated serum levels of free thyroxine or free triiodothyronine, or both. Therefore, thyrotoxicosis is divided into two subtypes: thyrotoxicosis with hyperthyroidism such as Graves’ disease and Plummer’s disease, and thyrotoxicosis without hyperthyroidism such as painless and subacute thyroiditis. Here, I describe the differential diagnosis of hyperthyroidism; differentiation between Graves’ disease and Plummer’s disease; differentiation between Graves’ disease with and without thyroid storm. Further, I show the differentiation among Graves’ disease, painless thyroiditis and subacute thyroiditis. I believe that the proper diagnosis leads to appropriate treatment and management of thyrotoxicosis. J Endocrinol Metab. 2019;9(5):127-132 doi: https://doi.org/10.14740/jem600

Mean peak systolic velocity of superior thyroid artery for the differential diagnosis of thyrotoxicosis: a diagnostic meta-analysis

BackgroundThyrotoxicosis is often caused by destructive thyroiditis (DT) or Graves’ disease (GD), and a prompt and accurate differential diagnosis for thyrotoxicosis is needed as management strategy differs. A meta-analysis of published literature was performed to evaluate the diagnostic accuracy for differentiating GD from DT patients by the measurement of mean peak systolic velocity of superior thyroid artery (STA-PSV) using ultrasonography.MethodsThe databases of Embase, Pubmed, Cochrane, Web of Science, Wanfang, and CNKI were retrieved without time limit to identify eligible studies. The statistical information and scientific quality were assessed and classified. The data were analyzed using Stata12.0 software.ResultsA total of 11 studies with 1052 cases only from Asia were included. Meta-analysis results showed the pooled sensitivity and pooled specificity of STA-PSV by ultrasonography were 0.86 (95% CI, 0.80–0.90) and 0.93 (95% CI, 0.86–0.97) in distinguishing GD from DT, respectively, with the AUC of 0.94 (95% CI, 0.92–0.96) .ConclusionSTA-PSV by ultrasonography is a useful diagnostic method in differentiating GD from DT. More studies from other countries are needed to further evaluate the accuracy of STA-PSV for the differential diagnosis of thyrotoxicosis.

Differential Diagnosis of Thyrotoxicosis

Differential Diagnosis of Thyrotoxicosis