Graves’ Disease Following Subacute Thyroiditis

Subacute thyroiditis is an inflammatory thyroid disease caused by viral infection. Graves’ disease is an autoimmune thyroid disease caused by thyrotropin (TSH) receptor antibody (TRAb). Graves’ disease following subacute thyroiditis is rare, and only a few cases have been reported. A 58-year-old woman presented with anterior neck pain and swallowing difficulty. Laboratory tests showed elevated FT4, low TSH, normal TRAb, and elevated erythrocyte sedimentation rate. Thyroid ultrasonography (US) revealed focal, ill-defined hypoechoic areas in both thyroid lobes. The patient was treated with corticosteroid, and symptoms subsided after 1 month. Three months later, she complained of tremor and palpitation. Thyroid function testing showed hyperthyroidism with the positive conversion of TRAb, indicating Graves’ disease. Doppler US showed increased vascular flow in both thyroid lobes. She started treatment for hyperthyroidism with methimazole.

515Association between hysterectomy and risk of thyroid cancer

Background Hysterectomy (surgical removal of the uterus) has been consistently associated with increased thyroid cancer risk. While there may be a biologic explanation, increased ascertainment (over-diagnosis) because of greater healthcare use by women having this procedure might also contribute to the observed increased risk. We explored this association considering indications for hysterectomy, age at hysterectomy, and the potential for the association to be mediated by increased contact with health professionals or increased thyroid function testing. Methods We recruited 730 women diagnosed with thyroid cancer and 785 age-matched population controls. We estimated odds ratios (OR) using logistic regression to assess the associations and used causal mediation analysis to investigate potential mediation. Results Prior hysterectomy was associated with an increased thyroid cancer risk (OR = 1.55, 95% CI: 1.14-2.12). When stratified by indication for hysterectomy, the increased risk was apparent only among those who had undergone hysterectomy for bleeding disorders (OR = 1.79, 95% CI: 1.26-2.56). Additionally, the association varied by age at hysterectomy (<55 years, OR = 1.68, 95% CI: 1.22-2.31 versus ≥ 55 years, OR = 0.87, 95% CI: 0.42-1.81). Around 30% of the association was mediated by more frequent use of healthcare services. Conclusions Hysterectomy for bleeding disorders was associated with an increased risk of thyroid cancer among women and a moderate proportion of this appeared due to frequent medical contact. Key messages The way in which women use health services probably explains at least some of the association between hysterectomy and risk of thyroid cancer.

Case Report: De Quervain’s Thyroiditis as a Long-Term Sequelae Complication to SARS-CoV-2 Infection

A 44-year-old man presented with an enlarged painful lower anterior neck lump with elevated serum concentrations of free thyroxine (T4) and tri-iodothyronine (T3), alongside the presence of antithyroid peroxidase antibodies. Prior to presentation, the patient was demonstrating recovery from a SARS-CoV-2 infection that required sedation, intubation, and invasive ventilation in the intensive care unit (ICU) for 11 days. Ultrasound examination of the thyroid demonstrated features of De Quervain’s (subacute) thyroiditis. This corresponded to the clinical picture, and continuous thyroid function tests were arranged. Emerging evidence throughout the SARS-CoV-2 pandemic describes the long-term sequelae of the infection, including developing atypical effects on the thyroid gland. This case report emphasises the association of painful subacute thyroiditis with post-viral infection and its manifestation during recovery from severe SARS-CoV-2, suggesting that follow-up thyroid function testing should be considered in patients discharged from the ICU who develop neck discomfort.

Interference Due to Heterophilic Antibody, Biotin and Thyroid Hormone Autoantibody

Purpose: Immunoassay is susceptible to interference by other substances in the serum. The main substances interfering with thyroid function testing include heterophilic antibody, biotin, thyroid hormone autoantibody, and Macro-TSH. We reported a patient with fraudulently elevated FT4 and TSH and described various common experimental methods used to explore the existence of substances interfering with thyroid function testing.Methods and Results: FT4 and TSH were significantly lower when measured on the Architect platform (FT4: 7.09 pmol/L, TSH: 58.94 µIU/ml). Polyethylene glycol precipitation showed lower FT4 and TSH, suggesting the presence of a high molecular weight interfering substance. Heterophile blocking tube study showed heterophilic antibody interfered with TSH detection. 125I-hTSH binding study and radioimmunoprecipitation assay indicated that the patient didn’t contain anti-TSH autoantibody. The new generation of Elecsys immunoassay kit indicated that biotin interfered with TSH detection. Radioimmunoprecipitation assay showed that all four kinds of thyroid hormone autoantibodies were positive. After reviewing 24 literatures, we provided the diagnostic strategy for investigation of interferences with thyroid function immunoassays.Conclusion: We reported a case with falsely elevated TSH due to the combined action of heterophilic antibody and biotin and fraudulently elevated FT4 caused by thyroid hormone autoantibody. When there is a discrepancy between thyroid function and clinical manifestation, the presence of immunoassay interference with one or more indicators needs to be considered.

Pituitary thyrotoxicosis presenting as abnormal thyroid function testing during pregnancy: a case report

Background Central hyperthyroidism is a rare form of hyperthyroidism caused by thyrotrope pituitary adenomas. It is characterized by elevated thyroid-stimulating hormone alongside high thyroxine and triiodothyronine. Goiter is the most common symptom of central hyperthyroidism. Surgical resection as well as somatostatin analog therapy typically achieve resolution of hyperthyroid symptoms and restoration of a euthyroid state. Case presentation We report the case of a 30-year-old primigravida Caucasian/White female who presented with abnormal thyroid function testing results and multinodular goiter during pregnancy. Postpartum, she was found to have multinodular goiter on physical examination as well as persistent elevated thyroid-stimulating hormone with elevated free thyroxine and free triiodothyronine. Magnetic resonance imaging disclosed a large pituitary macroadenoma, and she subsequently underwent resection of the mass. She achieved a sustained euthyroid state postoperatively. Conclusions This case shows how central hyperthyroidism can present without the more apparent symptoms of thyrotoxicosis and that successful resolution of central hyperthyroidism may be achieved postoperatively.

Comparison of ATA and Updated ACOG Guidelines for Thyroid Disease in Pregnancy. Russian translation

Thyroid dysfunction is relatively common in pregnancy. The American Thyroid Association (ATA) published its most recent guidelines regarding the management of thyroid disorders in pregnancy in 2017. The American College of Obstetricians and Gynecologists (ACOG) has recently published an updated practice bulletin for thyroid disease in pregnancy that supersedes its previous guidance published in 2015. A comparison of the similarities and differences between the clinical guidelines from the ATA and ACOG can serve to highlight areas of uncertainty where additional studies are needed and may also demonstrate areas where endocrinologists and obstetricians may elect differing approaches to clinical care. The ACOG and ATA guidelines recommend similar approaches to the interpretation of thyroid function testing during gestation and to the management of thyroid cancer, thyroid nodules, gestational thyrotoxicosis, and postpartum thyroiditis Both strongly recommend levothyroxine (L-T4) treatment for overtly hypothyroid pregnant women, and both recommend against the use of T3-containing thyroid hormone preparations when treating hypothyroidism in pregnancy.

Severe primary hypothyroidism in an apparently asymptomatic 19-year-old woman: a case report

Background Hypothyroidism is diagnosed on the basis of laboratory tests because of the lack of specificity of the typical clinical manifestations. There is conflicting evidence on screening for hypothyroidism. Case presentation We report a case of an apparently healthy 19-year-old Kuwaiti woman referred to our clinic with an incidental finding of extremely high thyroid-stimulating hormone (TSH), tested at the patient’s insistence as she had a strong family history of hypothyroidism. Despite no stated complaints, the patient presented typical symptoms and signs of hypothyroidism on evaluation. Thyroid function testing was repeated by using different assays, with similar results; ultrasound imaging of the thyroid showed a typical picture of thyroiditis. Treatment with levothyroxine alleviated symptoms and the patient later became biochemically euthyroid on treatment. Conclusion There is controversy regarding screening asymptomatic individuals for hypothyroidism; therefore, it is important to maintain a high index of suspicion when presented with mild signs and symptoms of hypothyroidism especially with certain ethnic groups, as they may be free of the classical symptoms of disease.