Resistant thyrotoxicosis in a patient with graves disease: a case report

Unusual Presentations of Thyrotoxic Tricuspid and Mitral Regurgitations in 62 Adults: A Systematic Review of Case Reports with In-depth Pathophysiological Review

Background

Thyrotoxicosis is related to cardiovascular mortality. This can be caused by several clinical manifestations involving the rare provocation of tricuspid regurgitation (TR) and mitral regurgitation (MR). However, there are still no clear data on thyrotoxic TR and/or MR. This study examines the progression of TR, MR, heart failure (HF) and pulmonary hypertension (PH) in response to the thyrotoxic heart manifestations, clinical characteristics and treatment approaches.

Methods

A PRISMA-based systematic search was conducted using PubMed and other databases up to 17 June 2023. The outcomes of this study were TR, MR, HF and PH with their progression on follow-up, clinical characteristics and treatment approaches.

Results

A total of 57 case reports involving 62 patients (45.77 ± 13.41 years) were included in this study. They were predominantly women (n=50; 80.65%) and diagnosed with Graves' disease (n=41; 75.81%). All patients were diagnosed with thyrotoxicosis, and this included 23 (37.10%) cases of thyroid storm. From echocardiographic studies, several patients improved clinically within the first 6 months of follow-up, including 20 TR patients (83.33%) in 6 months, nine MR patients (69.23%) in 3 months, eight HF patients (66.67%) in 2 months and 16 PH patients (76.19%) in 6 months.

Conclusion

Several mechanisms are involved in thyrotoxic TR and/or MR, including the direct thyroid hormone effect and the indirect effect of other hyperthyroidism-associated factors. Patients with thyrotoxic TR and/or MR, including those with HF and PH, can experience clinical and structural improvements following hyperthyroidism treatment in the first 6 months.

Rare Presentation of Thyrotoxicosis Defying Methimazole Treatment: A Case Series

Thyrotoxicosis, also known as hyperthyroidism, is a condition characterized by the excessive production of thyroid hormones by the thyroid gland. Besides Graves' disease, other common causes of thyrotoxicosis include toxic multinodular goiter, toxic adenoma, and subacute thyroiditis. The treatment of thyrotoxicosis depends on the underlying cause and may include medications (e.g., antithyroid drugs, beta-blockers), radioactive iodine therapy, or surgical removal of the thyroid gland (thyroidectomy). In this report, we present two instances of thyrotoxicosis where conventional high doses of antithyroid treatment failed to control the condition effectively. This failure prompted the exploration of alternative therapeutic interventions. These cases highlight the intricacies involved in managing thyrotoxic crises that do not respond to methimazole (MMI), emphasizing the necessity for innovative approaches such as plasmapheresis and thyroidectomy. Understanding such scenarios is vital for enhancing the care provided to patients encountering resistance to standard treatments. The distinct clinical pathways and treatment strategies adopted in these cases offer valuable insights into this disease management, particularly concerning resistance to MMI.

Carbimazole-Resistant Grave's Thyrotoxicosis is a Diagnostic and Therapeutic Dilemma, Case Report with Literature Review

Background

Carbimazole (CBZ) (or methimazole) is the most used drug inducing and maintaining remission in thyrotoxicosis, especially Grave's disease (GD). Rarely, situations arise when patients do not respond to recommended or even supratherapeutic doses of CBZ. It poses a challenge to diagnose drug resistance and ultimately manage hyperthyroidism, which can otherwise be fatal if left untreated. Propylthiouracil (PTU) has been used as an alternative in such patients amid increased side effect risks. Additionally, definitive therapy has been recommended with ablation or surgery. However, the best modality of inducing euthyroidism in drug-resistant patients is yet to be established. On literature search, twenty similar cases were found in the literature search. This study summarizes the past literature with addition of a new case of anti-thyroid drug resistant (ATDR) GD.

Case Presentation

A 34-year-old female presented with a 5-day history of progressively worsening fatigue, heat intolerance, sweating, and palpitations. She was diagnosed with GD based on her thyroid function tests (TFTs) and started on CBZ and propranolol. Despite being compliant with CBZ 20 mg once daily and then twice daily, her TFTs remained unchanged for 4 months. However, patient revisited the emergency with continued thyrotoxicosis and unchanged TFTs. Her dose was eventually increased to 20 mg thrice daily, and administration under supervision did not improve her TFTs. The patient was shifted to PTU 150 mg thrice daily with steroids, with minimal improvement. The patient eventually underwent thyroidectomy to avoid long-term PTU use.

Conclusion

ATDR GD is rare and remains a diagnostic and therapeutic challenge. Optimal management should focus on carefully excluding other possibilities and shared decision-making in its management. Most patients may require definitive therapy; hence, arrangements should be made timely with simultaneous attempts to reduce the thyrotoxic state, which otherwise poses a continued threat to patients' life with potentially serious complications.

Lithium as an alternative option in thionamide-resistant Graves' disease

Conventional treatments for Graves' disease include thionamides, radioactive iodine therapy (RAI), and thyroidectomy. Occasionally, patients may develop resistance to thionamides and may require additional treatment. We present the case of an adolescent girl with thionamide-resistant Graves' disease who was successfully treated with lithium and subsequent RAI after stabilizing her thyroid hormone levels. Following RAI, the patient developed hypothyroidism, and thyroxine replacement therapy was initiated. This case highlights the potential of lithium as a safe and effective alternative for controlling hyperthyroidism in Graves' disease and its role in preparing patients for more definitive treatment.

Non-thionamide antithyroid drug options in Graves' hyperthyroidism

INTRODUCTION

The thionamide anti-thyroid drugs namely carbimazole, methimazole, and propylthiouracil, have been the predominant therapy modality for Graves' hyperthyroidism for over 60 years. Although these agents have proven efficacy and favorable side-effect profiles, non-thionamide alternatives are occasionally indicated in patients who are intolerant or unresponsive to thionamides alone. This review examines the available non-thionamide drug options for the control of Graves' hyperthyroidism and summarizes their clinical utility, efficacy, and limitations.

AREAS COVERED

We reviewed existing literature on mechanisms, therapeutic utility, and side-effect profiles of non-thionamide anti-thyroid drugs. Established non-thionamide agents act on various phases of the synthesis, release, and metabolism of thyroid hormones and comprise historical agents such as iodine compounds and potassium perchlorate as well as drug repurposing candidates like lithium, glucocorticoids, beta-blockers, and cholestyramine. Novel experimental agents in development target key players in Graves' disease pathogenesis including B-cell depletors (Rituximab), CD40 blockers (Iscalimab), TSH-receptor antagonists, blocking antibodies, and immune-modifying peptides.

EXPERT OPINION

Non-thionamide anti-thyroid drugs are useful alternatives in Graves' hyperthyroidism and more clinical trials are needed to establish their safety and long-term efficacy in hyperthyroidism control. Ultimately, the promise for a cure will lie in novel approaches that target the well-established immunopathogenesis of Graves' disease.

Very rare case of Graves' disease with resistance to methimazole: a case report and literature review

BACKGROUND

Methimazole (MMI) is used to treat hyperthyroidism in Graves' disease. It is rare to encounter patients in whom hyperthyroidism cannot be controlled using high doses of MMI.Case presentation: A 21-year-old woman was referred to our hospital because of MMI-resistant Graves' disease. Although her MMI dose had been increased to 120 mg/day, her serum thyroid hormone concentration was too high to be measured. Additional therapy with lithium carbonate, and then with dexamethasone and inorganic iodine, was initiated. After 14 days, the patient's serum thyroid hormone concentration normalized, while she was taking 150 mg/day MMI, 800 mg/day lithium carbonate, 6 mg/day dexamethasone and 306 mg/day inorganic iodine, and total thyroidectomy was then performed. The patient was discharged 8 days after the thyroidectomy and experienced no major complications.

CONCLUSIONS

We have presented a rare case of Graves' disease that was resistant to high-dose MMI. Combination therapy of MMI with lithium carbonate, dexamethasone and inorganic iodine may represent a therapeutic option for the preoperative preparation of patients with MMI-resistant Graves' disease.

Use of Adjunctive Therapy to Achieve Preoperative Euthyroidism in Graves' Disease: A Case Report

BACKGROUND Graves' disease is an autoimmune disease of the thyroid gland and it is considered the most common cause of hyperthyroidism. It is characterized by particular eye manifestations, skin changes, and pretibial myxedema in addition to the signs and symptoms of hyperthyroidism. Graves' disease can be diagnosed based on clinical presentation and low thyroid stimulating hormone (TSH) and elevated free T4 (FT4) levels. Presence of TSH receptor antibody (TRAb) in the serum confirms the diagnosis of Graves' disease. Imaging studies like radioactive iodine scan will show a high and diffuse uptake. Graves' disease can be managed with three different treatment modalities: antithyroid medications, radioactive iodine, or surgical removal of the thyroid gland. Whenever surgery is indicated, careful preoperative management to achieve euthyroidism is needed to optimize the surgical outcome. CASE REPORT This is a case of a 37-year-old Saudi male known to have Graves' disease for 2 years who presented to the endocrine surgery clinic with neck swelling, difficulty breathing, and change in voice. After multiple attempts to control his fluctuating thyroid levels, the team eventually managed to achieve a euthyroid state in the patient with the addition of saturated solution of potassium iodide (SSKI), and thus rendering him eligible for urgent surgery. CONCLUSIONS We report this case to show that SSKI can be used as adjunctive therapy to achieve a preoperative euthyroid state in refractory Graves' disease.

Resistant Thyrotoxicosis due to Graves' Disease in Pregnancy: Case Report and Review of the Literature

The effective management of Graves' disease (GD) during pregnancy is crucial for maternal and neonatal well-being. Conventional treatment of GD during pregnancy includes antithyroid drugs (ATDs) and surgery, ideally during the second trimester. We report a 27-year-old woman with GD and we present the course of GD during her three consecutive pregnancies. During the first pregnancy, thyrotoxicosis was successfully treated with low doses of antithyroid drugs; in the second pregnancy, thyrotoxicosis was only controlled at the third trimester; while in the third pregnancy, our patient presented with treatment-resistant thyrotoxicosis, which was finally managed with corticosteroids in adjunction with ATDs. Although hyperthyroid, the patient maintained her fertility. Resistance to ATD is a rare condition and in our case was adequately controlled with corticosteroids.

Refractory Graves' Disease Successfully Cured by Adjunctive Cholestyramine and Subsequent Total Thyroidectomy

The three major forms of treatment for Graves thyrotoxicosis are antithyroid drugs, radioactive iodine therapy and thyroidectomy. Surgery is the definitive treatment for Graves thyrotoxicosis that is generally recommended when other treatments have failed or are contraindicated. Generally, thyrotoxic patients should be euthyroid before surgery to minimize potential complications which usually requires preoperative management with thionamides or inorganic iodine. But several cases of refractory Graves' disease have shown resistance to conventional treatment. Here we report a 40-year-old female patient with Graves' disease who complained of thyrotoxic symptoms for 7 months. Her thyroid function test and thyroid autoantibody profiles were consistent with Graves' disease. One kind of thionamides and β-blocker were started to control her disease. However, she was resistant to nearly all conventional medical therapies, including β-blockers, inorganic iodine, and two thionamides. She experienced hepatotoxicity from the thionamides. What was worse is her past history of serious allergic reaction to corticosteroids, which are often used to help control symptoms. A 2-week regimen of high-dose cholestyramine improved her uncontrolled thyrotoxicosis and subsequent thyroidectomy was successfully performed. In conclusion, cholestyramine could be administered as an effective and safe adjunctive agent for preoperative preparation in patients with severe hyperthyroid Graves's disease that is resistant to conventional therapies.

Role of Cholestyramine in Refractory Hyperthyroidism: A Case Report and Literature Review

BACKGROUND

Hyperthyroidism is a common disease that usually responds to the conventional therapy of anti-thyroidal medications (methimazole or PTU) and beta-blocker. Refractory hyperthyroidism is a rare condition in which hyperthyroidism fails to respond to the above therapy. Cholestyramine has been shown to decrease thyroid hormone level when added to the ongoing anti-thyroidal medications.

CASE REPORT

A 52-year-old woman with past medical history of enlarging goiter presented with obstructive symptoms of worsening shortness of breath and snoring. Admission thyroid function test showed mild hyperthyroidism (suppressed TSH, slightly high FT4, and high normal FT3) that worsened after she received a CT scan with contrast and failed to respond to a 3-week course of high-dose dexamethasone, high-dose carbimazole, and up-titrated propranolol. Five days after cholestyramine was added, her FT4 decreased by 30% and normalized after 12 days. The patient underwent total thyroidectomy as definitive treatment for the hyperthyroidism and for the obstructive symptoms.

CONCLUSIONS

Cholestyramine is an effective additional treatment for hyperthyroidism and may be an effective treatment for refractory iodine-induced hyperthyroidism. The possibility of self-remission (natural course) is less likely given the dramatic and rapid response to cholestyramine.

Thyroid disorders

All forms of thyroid diseases are much more frequently observed in women than men, although the reasons are still not completely elucidated.Hyperthyroidism is defined by elevated circulating free thyroid hormones. The prevalence is about 2 % in women and 0.2 % in men. The most frequent causes are various forms of thyroid autonomy in elderly women and Graves' disease, which occurs mostly in younger women.Hypothyroidism is defined by a lack of thyroid hormones. It is a common endocrine disorder caused by autoimmune thyroiditis (Hashimoto thyroiditis), iodine deficiency or following surgery or radioiodine therapy. Thyroxine requirements depend on fat-free mass and are, therefore, somewhat higher in males who are more often undersubstituted. In pregnancy lower TSH-reference ranges have to be considered and thyroid function should be monitored throughout pregnancy to avoid harm to the foetus caused by maternal thyroid dysfunctions. If overtreated women more often feature fractures, whereas males more often develop atrial fibrillation.