Thyroid function after subtotal thyroidectomy in patients with Graves' hyperthyroidism

Mechanisms and Treatment Options for Hyperthyroid-Induced Osteoporosis: A Narrative Review

Normal thyroid hormone levels are crucial for the homeostasis of many metabolic cycles and processes throughout the human body. Thyroid dysfunction, such as thyrotoxicosis, can result from many different etiologies, including Graves' disease (GD), toxic multinodular goiter (MNG), and toxic adenoma. These hyperthyroid disease states can cause devastating complications and disease, including the disruption of the bone remodeling cycle and skeletal development, which can result in osteoporosis. Osteoporosis is characterized by a decrease in bone mineral density and a propensity for fragility fractures. In addition to patients with overt hyperthyroidism, studies have provided evidence of other high-risk patient demographics, such as individuals with subclinical hyperthyroidism and postmenopausal women, who may be at an increased risk for the development of secondary osteoporosis. The treatment of patients with hyperthyroid-induced osteoporosis often requires a multifaceted management plan that may be unique to each patient's situation. Antithyroid therapy is often the first step in treating this disease and may include thioamide medications. Radioactive iodine-131 therapy (RAI) and the surgical removal of the thyroid gland may also be reasonable approaches for restoring normal thyroid function. Following thyrotoxicosis mitigation, antiresorptive drugs such as bisphosphonates, calcitonin, and selective estrogen receptor modulators (SERMs) may be used to counteract decreased bone mineral density (BMD). Additionally, the implementation of vitamin D, calcium supplements, and weight-bearing exercise may also reduce bone loss. While the effects of thyroid stimulating hormone (TSH) and triiodothyronine (T3) on bone remodeling have been studied in the past, more research is needed to identify unknown mechanisms and develop future improved treatments for this condition.

A Case of Recurrent Thyrotoxicosis in a Thyroglossal Duct Cyst 18 Years Following Thyroid Surgery

Graves' disease (GD) is an immune-mediated condition related to high thyroid-stimulating immunoglobulin levels. Here, we present a rare case of recurrent thyrotoxicosis that developed in a thyroglossal duct cyst (TGDC) and the residual thyroid tissue in a 46-year-old female following subtotal thyroidectomy. In 2005, she was diagnosed with GD causing thyrotoxicosis and treated with subtotal thyroidectomy. In 2022, she was seen at our clinic with a neck swelling gradually growing in size over the last 10 years. On examination, the mass was found to be moving with tongue protrusion. She was on thyroxin 100 mcg daily, and the dose was reduced gradually until she was maintained on no therapy for hypothyroidism and was still thyrotoxic. The combined clinical, laboratory thyroid scintigraphy and ultrasonographic features favored early developing recurrent Graves' disease in the thyroid residual and TGDC. She was started on carbimazole and was referred for surgery. Our case represents a rare occurrence of recurrent GD in the thyroid residual and TGDC.

Carbimazole-Induced Agranulocytosis in a Previously Stable Patient: A Case Report and Literature Review

Carbimazole-induced agranulocytosis is a rare condition. A 48-year-old female patient with a history of hyperthyroidism for several years presented with generalized fatigue and chest pain associated with palpitations; the patient was stable on carbimazole therapy. She was previously on carbimazole 15 mg once daily (OD) and, three months later, was reduced to 10 mg OD as symptoms were controlled. She was taking propranolol, and it was stopped as she was not having any palpitations. This time, however, she presented mainly with palpitations at night associated with chest pain and generalized fatigue ongoing for the last one week. Her laboratory results showed agranulocytosis with reduced white cell count and neutrophil count in the absence of any evidence of infection. Her carbimazole was stopped, and the patient was referred to ear, nose, and throat surgeons for consideration of thyroidectomy. The patient underwent subtotal thyroidectomy, and her symptoms resolved following surgery.

Short-Term Outcomes of Surgery for Graves' Disease in Germany

BACKGROUND

Surgical treatment of Graves' disease (GD) has a potentially increased incidence of postoperative hypoparathyroidism, recurrent laryngeal nerve palsy (RLNP) and bleeding. The aim of this study was to evaluate the current extent of surgery for the treatment of GD and its safety as a short-term outcome.

METHODS

Patients who underwent thyroid resection for GD were identified from the prospective StuDoQ/Thyroid registry. Patient data were retrospectively analyzed regarding demographics, surgical procedures and perioperative outcomes. Statistics were performed with Student's t-test or Fisher's exact test and multivariate Cox regression analysis. The level of statistical significance was set at p < 0.05.

RESULTS

A total of 1808 patients with GD with a median age of 44 (range 14-85) years were enrolled in a 25-month period by 78 departments, of which 35.7% (n = 645) had an endocrine orbitopathy and 0.1% (n = 6) had thyrotoxic crisis. Conventional open surgery was used in 98.6% of cases and minimally invasive or remote-access approaches were used in 1.4%. Total thyroidectomy was performed in 93.4% of cases (n = 1688). Intraoperative neuromonitoring (IONM) was used in 98.9% (n = 1789) of procedures. In 98.3% (n = 1777) at least one parathyroid gland was visualized and in 20.7% (n = 375) parathyroids were autografted. The rates of unilateral and bilateral transient RLNP were 3.9% (n = 134/3429 nerves at risk) and 0.1% (n = 4/3429 NAR). The rates of transient RLNP tended to be higher when intermittent IONM was used compared to continuous IONM (4.1% vs. 3.4%, p < 0.059). The rate of transient postoperative hypoparathyroidism was overall 29% (n = 525/1808). Multivariate analysis revealed fewer than 300 thyroid resections and fewer than 15 thyroid resections for GD per year, male sex, BMI > 30, autotransplantation of parathyroid glands and previous bilateral thyroid surgery as independent risk factors for postoperative temporary hypoparathyroidism. Reoperations for bleeding (1.3%) were rare.

CONCLUSION

Total thyroidectomy with IONM is safe and currently the most common surgical therapy for GD in Germany. Postoperative hypoparathyroidism is the major complication which should be focused on.

Surgical management of benign thyroid disease in children

Benign thyroid disease in children represents a wide spectrum of disease. While most benign thyroid disorders may be either monitored or managed medically, surgery is an important treatment, particularly for Graves' disease or large multinodular goiters. Multidisciplinary teams including specialists in pediatric endocrinology, genetics, radiology, pathology and surgery at high volume centers offer the safest and most effective management.

Chemically or surgically induced thyroid dysfunction altered gut microbiota in rat models

Thyroid hormones are essential for the regulation of energy homeostasis and metabolic processes. However, the relationship between thyroid function and host gut microbial communities is not properly understood. To determine whether and how gut microbiota is associated with thyroid function, metagenomics analysis of the bacterial population in fecal samples of rat models of hyperthyroidism (induced by levothyroxine) and hypothyroidism (induced by propylthiouracil or thyroidectomy) was conducted through 16S rRNA gene sequencing. Our results revealed that all thyroid dysfunction models were definitely established and gut microbial composition varied according to different thyroid functional status. The relative abundance of Ruminococcus was significantly higher in the hyperthyroidism group (HE) vs both the normal and hypothyroidism groups (HO) while S24-7 was significantly higher in the HO group. The population of Prevotellaceae and Prevotella were significantly lower in the HO group vs the normal. Firmicutes and Oscillospira were significantly higher in the SHO (surgery-induced hypothyroidism) group, while Prevotellaceae and Prevotella showed lower abundance in the SHO group than the SHAM group. Present results suggest that thyroid functions may have the potential to influence the profile of gut microbiota and could be used as foundation to investigate interaction mechanism between thyroid and gut microbiome.

Retrospective Study of Tc-99m Thyroid Scan in Patients with Graves' Disease: Is There Significant Difference in Lobar Activity?

PURPOSE

Graves' disease (GD) is the most common cause of hyperthyroidism. It was reported that the right thyroid lobe is generally larger, and it is more likely to be affected by thyroid disorders. The aim of the current study is to verify preferential affection of one of the thyroid lobes and incidence of higher activity of either thyroid lobe in patients with GD through analysis of quantitative data of Tc-99m thyroid scan and possible relation of different thyroid lobar activity to gender, age, and total thyroid uptake (TTU) level.

MATERIALS AND METHODS

Retrospective analysis of quantitative data of Tc-99m thyroid scan in patients with GD was done. Total and lobar thyroid uptake levels were analyzed and correlated with age, gender, and TTU.

RESULTS

GD was reported in 222 patients, representing 76.6% of those with hyperthyroidism, women represent 70.3% of patients. The right thyroid lobe uptake (RLU) figures were significantly higher compared to the left in the whole group as well as in women and in young patients (<40 years). This significance was lost in men and in old patients. Equal lobar uptake was found in 11 patients. 138 patients (62.2%) had higher RLU, while the remaining 73 patients (32.8%) had higher left thyroid lobe uptake, with statistically significant difference. This significant difference was found in women and in young patients and was absent in men and old patients. There is an increase in the incidence of patients with higher RLU in association with an increase in TTU. All women with TTU >30% had higher RLU figures.

CONCLUSION

There is significant preferential thyroid lobar affection in favor of the right thyroid lobe in patients with GD, with significantly higher RLU figures and significantly more incidence of patients with higher right lobar activity. This significance is maintained in women and in young patients and lost in men and old patients. The incidence of higher right thyroid lobe activity also increases in association with increase in TTU. Our results emphasize the value of Tc99m thyroid scan in patients with GD, especially when surgery is the treatment of choice, helping to tailor suitable surgical procedure for each individual patient.

Degree of technical difficulty of thyroidectomy for autoimmune thyroid disease

BACKGROUND

Our goal was to elucidate the differences in degree of technical difficulty of thyroidectomy in patients with autoimmune thyroid diseases.

METHODS

Charts of adult patients who had undergone thyroidectomy were reviewed. Patients with Hashimoto's Thyroiditis (HT) or Graves' Disease (GD) were individually compared to a control group of patients with early stage malignancy or goiter.

RESULTS

The HT (n = 65) group was significantly more likely to have friable (P = .001) and fibrotic (P < .001) thyroids, longer operative times (P = .02), and a 22-modifier (P = .005). The GD (n = 169) group was significantly more likely to have friable (P < .001), vascular (P < .001), fibrotic (P = .038), and heavy (P = .002) thyroids, longer operative times (P = .03), increased length of stay (P = .01) and a 22-modifier (P = .01).

CONCLUSION

Our experience at an institution with a high-volume thyroid practice demonstrates that patients with autoimmune thyroid disease have consistent qualitative changes of the thyroid and significantly increased operative times and surgical difficulty.

Microencapsulation of porcine thyroid cell organoids within a polymer microcapsule construct

Hypothyroidism is a common condition of hormone deficiency, and oral administration of thyroid hormones is currently the only available treatment option. However, there are some disadvantages with this treatment modality including compliance challenges to patients. Therefore, a physiologically based alternative therapy for hypothyroidism with little or no side-effects is needed. In this study, we have developed a method for microencapsulating porcine thyroid cells as a thyroid hormone replacement approach. The hybrid wall of the polymer microcapsules permits thyroid hormone release while preventing immunoglobulin antibodies from entry. This strategy could potentially enable implantation of the microcapsule organoids containing allogeneic or xenogeneic thyroid cells to secret hormones over time without the need for immunosuppression of recipients. Porcine thyroid cells were isolated and encapsulated in alginate-poly-L-ornithine-alginate microcapsules using a microfluidic device. The porcine thyroid cells formed three-dimensional follicular spheres in the microcapsules with decent cell viability and proliferation. Thyroxine release from the encapsulated cells was higher than from unencapsulated cells ( P < 0.05) and was maintained during the entire duration of experiment (>28 days). These results suggest that the microencapsulated thyroid cell organoids may have the potential to be used for therapy and/or drug screening.

Hypothyroidism after a cancer diagnosis: etiology, diagnosis, complications, and management

Hypothyroidism is a common disease that is easily treated in the majority of cases, when readily diagnosed; however, presentation of an aggregate of its symptoms is often clinically overlooked or attributed to another disease and can potentially be lethal. Already prevalent in older women, its occurrence in younger patients is rising as a result of radiation therapy, radioactive iodine therapy, and newer antineoplastic agents used to manage various malignancies. The presence of nonspecific constitutional symptoms and neuropsychiatric complaints in cancer patients can be attributed to a myriad of other diagnoses and therapies. Thyroid dysfunction can be easily overlooked in cancer patients because of the complexity of cancer's clinical picture, particularly in the pediatric population. Underdiagnosis can have important consequences for the management of both hypothyroidism and the malignancy. At minimum, quality of life is adversely affected. Untreated hypothyroidism can lead to heart failure, psychosis, and coma and can reduce the effectiveness of potentially life-saving cancer therapies, whereas iatrogenic causes can provoke atrial fibrillation and osteoporosis. Consequently, the diagnosis and treatment of hypothyroidism in cancer patients are pertinent. We summarize the history, epidemiology, pathophysiology, clinical diagnosis, and management of hypothyroidism in cancer patients.