Etiology of Iodine Deficiency

Iodine is an essential substrate in the synthesis of the thyroid hormones L-thyroxine (T4) and L-triiodothyronine (T3). The normal human thyroid gland releases about 65 (ig of hormonal iodine to the circulation per day, which represents the minimum daily requirement of iodine. Iodine requirements increase during puberty, pregnancy, and lactation. Iodine intake is considered adequate when it is between 100 and 200 ig day (Table 3-4). The principal source of iodine intake is from diet or...

Surgical Applications

Because of their fairly central position in the abdominal cavity, the adrenal glands cannot be felt, and few tumors grow large enough to be palpated. Approaches to the gland can be made through the posterior, lateral, and anterior surfaces. Laparoscopic adrenalectomy has become in recent years the technique of choice for most adrenal tumors. Surgical techniques are described in greater detail in other chapters of this book. The anatomic landmarks are mentioned here as an introduction. The...

Localization Studies

Localization studies are indicated in all patients in whom the diagnosis of primary aldosteronism has been confirmed because aldosterone-producing adenomas and idiopathic hyperaldosteronism are not always distinguishable by biochemical tests. Visualizing an adrenal tumor or detecting unilateral excessive aldosterone production by means of localization studies greatly facilitates the selection of patients for adrenalectomy. Figure 68-3 is an algorithm for selecting the patients who are most...

Morphologic Changes in Endemic Goiter

An increase in thyroid gland mass often accompanies the physiologic changes in response to iodine deficiency. Generalized epithelial hyperplasia occurs, with cellular TABLE 3-5. Relation Among Prevalence of Goiter and Cretinism and Severity of Iodine Deficiency Median Level of Urinary Iodine Prevalence of Goiter Prevalence of Cretinism Severity of IDD (Hg L) ( ) ( ) No deficiency 100 5 0 hypertrophy and reduction in follicular spaces. In chronic iodine deficiency, the follicles become inactive...

Somatostatinoma

Somatostatinomas are rare endocrine tumors of the pancreas or duodenum that secrete excessive amounts of somatostatin. Somatostatin excess causes a syndrome characterized by steatorrhea, mild diabetes, and cholelithiasis. Somatostatin is an inhibitory hormone originally discovered in the hypothalamus in 1973. It was discovered by its ability to inhibit growth hormone and thus was called somatotropin release-inhibiting hormone. In 1977, Lans-Inge Larsson and P. O. Ganda and their colleagues...

Adrenal

Adrenal cortical insufficiency (Addison's disease) occurs with a prevalence of 93 to 110 per million population.65 Etiologies of Addison's disease include bilateral adrenal dysfunction induced by autoimmune reactions and tuberculosis, carcinoma, hemorrhage, and infarction. In addition, patients with multiple endocrine neoplasia type 2, von Hippel-Lindau disease, and familial pheochromocytoma who have had bilateral adrenalectomy for pheochromocytoma are another population who require life-long...

Secondary Adrenal Insufficiency Related to Exogenous Steroid Usage

Overall, the most common adrenal insufficiency is the secondary adrenal insufficiency resulting from exogenous steroid usage. Numerous and diverse conditions are treated with corticosteroids inflammatory bowel disease, asthma, arthritis, and dermatologie conditions, to name a few. Inhaled steroids are a mainstay of therapy for asthma and can produce the potential for adrenal insufficiency in both children and adults.12 Corticosteroids are part of the therapeutic regimen of transplantation...

Central Hypothyroidism

Abnormalities of the pituitary gland, such as pituitary tumor, ischemic lesion (Sheehan's syndrome), and iatrogenic events (surgical removal or radiation therapy), can cause central hypothyroidism with decreased pituitary TSH secretion. Other rare causes of pituitary lesions include tuberculosis, syphilis, hemochromatosis, sarcoidosis, histiocytosis, and aneurysms of the internal carotid artery. Hypothalamic lesions, such as suprasellar extension of pituitary tumors or craniopharyngioma,...

Diagnosis of Recurrence

After thyroid resection in patients with thyroid cancer some patients develop (1) local recurrence in the thyroid bed, (2) recurrence in the regional lymph nodes, usually ipsilateral, or (3) distant metastases. Tumor markers, Tg for papillary, follicular, and their Hurthle cell variations and calcitonin for MTC, are sensitive methods for detecting tumor persistence and recurrence. Because normal and abnormal thyroid tissue are the only sources of Tg in the peripheral blood, patients who have...

Iodide Metabolism and Uptake

Iodine usually enters the body as the result of dietary and water uptake, but it can also be found in various drugs, such as cough medicines, and in diagnostic agents. Dietary iodine intake varies widely throughout various parts of the world. The relationship between iodine intake and thyroid disease was first demonstrated by Chatin in 1852, but the practice of iodine supplementation of food and water, which he recommended, fell into disrepute and was not revived until the large-scale...

Lymphoma of the Thyroid

Primary lymphomas of the thyroid are rare, accounting for only 1 to 2 of thyroid malignancies and less than 2 of extranodal lymphomas.26 126128 Most thyroid lymphomas are non-Hodgkin's lymphomas of B-cell origin, although Hodgkin's disease of the thyroid has been described.126129 In a large proportion of cases, thyroid lymphomas are associated with Hashimoto's thyroiditis and histologically may be difficult to distinguish from this chronic lymphocytic disease.25 130 Follow-up studies have...

Thoracoabdominal Lateral Transthoracic Approach

The thoracoabdominal lateral transthoracic approach requires a large incision and opening of both the thoracic and peritoneal cavities. Because it provides only unilateral adrenal gland exposure, it is generally reserved for the following highly specific surgical circumstances 1. For very large tumors with substantial involvement of surrounding structures (especially the pancreas, spleen, and diaphragm on the left side and the liver, IVC, and diaphragm on the right), this approach affords the...

Differential Diagnosis of Hypoglycemia

As shown in Table 79-2, there are many causes of hypoglycemia. Hypoglycemia may be due to inhibition of glucose production in the liver and stimulation of glucose utilization by adipose and muscle cells. Hypoglycemic attacks secondary to an insulinoma are predominantly due to an overuse of glucose by the cells in the body. These attacks are episodic because of the intermittent secretion of insulin, especially in TABLE 79-2 Differential Diagnosis of Insulinoma Postprandial (reactive...

Technique of Parathyroidectomy

The diagnosis of hyperparathyroidism should be confirmed by the assessment of an elevated serum parathyroid hormone level using a two-site immunoassay.2729 Localization studies of enlarged parathyroid glands are necessary only in patients having exploration of the neck for persistent or recurrent hyperparathyroidism and in patients undergoing parathyroidectomy with local anesthesia.30,31 We believe that pre- and postoperative laryngoscopy to assess vocal cord function is mandatory in...

Hypothyroidism after Subtotal or Total Thyroidectomy

Subtotal thyroidectomy is still an excellent form of treatment for patients with Graves' disease, particularly when antithyroid drugs and 1311 therapy are not suitable.51 Surgical approach has three advantages over radioactive iodine therapy. First, the incidence of overt hypothyroidism is considerably less than after radioactive iodine therapy. Second, the incidence of hypothyroidism does not increase as much in later years. Third, patients with Graves' ophthalmopathy are less likely to...

Applied Surgical Anatomy

Anatomic subdivisions of the neck define its borders and are important to recognize.7 Recently, the Committee for Head and Neck Surgery and Oncology of the American Academy of Otolaryngology-Head and Neck Surgery has proposed an update of the neck dissection classification.8 The new guidelines present some minor revisions but do not differ substantially from the previous guideline. The sternocleidomastoid muscle is the most prominent landmark and covers the major vessels of the neck the carotid...

Medical and Surgical Treatment of Endemic Goiter

Endemic goiter is a preventable disease caused by iodine deficiency. According to statistics from the World Health Organization (WHO) in 1999, a total of 740 million people about 13 of the world's population are affected by endemic goiter alone.1 Clinically, the individual with endemic goiter may present with a diffuse to multinodular goiter. Biochemically, the urinary iodine excretion level is low, and the serum thyroxine (T4) level may be low or normal with an elevated thyroid-stimulating...

Hypoglycemic Crises

Hypoglycemia, defined as a blood glucose level less than 50 mg dL, occurs in a wide variety of clinical settings.45 This results from a failure of the normal homeostatic mechanisms previously discussed to achieve a balance in glucose production and utilization. In normal subjects, as plasma glucose decreases below the physiologic range, the counter-regulatory hormones epinephrine and glucagon are released followed by growth hormone and, ultimately, Cortisol. Signs and symptoms of hypoglycemia...

Prevalence

According to a global review in 1999, more than 2 billion people are at risk for iodine deficiency, this number representing 38 of the world's population. Approximately 741 million people from 130 countries have endemic goiter, representing 13 of the world population (Table 3-2).1 Most of the world's natural supply of iodine exists in the ocean as iodide. In high, mountainous areas and inland waters, the soil becomes leached of iodine by snow water and glaciation. Lowlands with heavy rainfall...

Nonthyroidal Illness as a Diagnostic Dilemma

Nonthyroidal illness is an alteration of serum thyroid hormone levels due to the presence of medical illness or fasting or after surgery. The nature of this disorder and a practical approach to this disorder have been well described.65,66 Initially, these patients present with low serum triiodothyronine (T3) levels due to decreased deiodinase 1 activity that converts T4 to T3. As the disease progresses, total T4 concentrations are reduced. When FT4 was measured by equilibrium dialysis, FT4...

Painless Thyroiditis

Painless thyroiditis is also known as lymphocytic thyroiditis with spontaneously resolving hyperthyroidism, subacute lymphocytic thyroiditis, painless lymphocytic thyroiditis, painless thyroiditis, or silent thyroiditis. Painless thyroiditis may occur sporadically or in the postpartum period. Both variations of subacute painless thyroiditis are considered to be autoimmune in origin. Like Hashimoto's thyroiditis, patients with painless thyroiditis have a high prevalence of anti-thyroid...

Summary

During thyroid operations, it is important to achieve a balance between the benefits of extensive resection for cure and the increased potential for complications. More extensive thyroid resections, especially when combined with bilateral and central neck and modified radical neck dissections, are associated with more postoperative complications, as are reoperations.7173 However, the literature contains numerous reports of total thyroidectomy and reintervention by experienced surgeons in which...

Thyroxine Suppressive Therapy and Diffuse Goiter

Diffuse nontoxic goiter can be sporadic or endemic. Iodine treatment is clearly the treatment of choice over T4 therapy in endemic cases, as shown by Hintze and colleagues129 in a 1989 multicenter trial. The most common cause of adult diffuse nontoxic goiter in nonendemic areas is chronic autoimmune thyroiditis. Both microsomal cytoplasmic and thyroid peroxidase autoantibodies are evident in 10.3 of adult women and 2.7 of adult men in clinical surveys of sporadic goiter. Conversely, about one...

Persistent Recurrent Hyperparathyroidism in MEN 1 Patients

Permanent hypoparathyroidism occurs in less than 10 of patients undergoing subtotal parathyroidectomy, and most series describe rates in the range of 1 to 2 .92-95 The rates of permanent hypoparathyroidism range from 10 to 30 for patients undergoing total parathyroidectomy with immediate autografting.85'92 Total parathyroidectomy, however, has been associated with recurrence rates as low as 0 (range, 0 to 60 ), whereas recurrence rates for subtotal parathyroidectomy have never been reported...

Hashimotos Thyroiditis

Hashimoto's thyroiditis, known as an autoimmune or chronic lymphocytic thyroiditis, is the leading cause of hypothyroidism. The pathogenesis of hypothyroidism is complex. Three mechanisms have been proposed (1) thyroid cell damage by the thyroid antibody-mediated complement attachment (2) T-cell-mediated cytotoxicity and (3) enhanced apoptosis (programmed cell death). The initial event is the formation of antibody in response to self-antigen such as thyroid peroxidase (TPO) and thyroglobulin...

Childhood Radiation Exposure

Two case-control studies with extensive follow-up of large populations of patients irradiated in childhood have been published.910 Shore and colleagues studied 2650 children irradiated between 1926 and 1957 in Rochester, New York, for an enlarged thymus compared with 4800 sibling control subjects.9 Thirty cancers and 59 benign thyroid nodules were detected in the treated group compared with 1 thyroid cancer and 8 benign nodules in the control group. The relative risk for this entire population...

Anterior Approach

The anterior approach is the most commonly used of the open approaches. This operation is carried out through incisions with which general surgeons are familiar. Our preferred incision is the bilateral subcostal or chevron, which affords easy access to all retroperitoneal structures. This incision provides excellent lateral, superior, and inferior exposure of not only both adrenals but also the surrounding solid organs. A unilateral subcostal incision can be used for disease confined to the...

Pathophysiology

The pathophysiology of an insulinoma is based on excessive secretion of insulin, which results in the clinical presentation of hypoglycemia. During the 1960s, insulinomas and other endocrine tumors of the gastrointestinal tract were found to share common cytochemical characteristics as well as a common neuroectodermal origin. This diverse group of tumors was thus classified under the amine precursor uptake and decarboxylation (APUD) concept.7 Although the APUD concept is no longer accepted in...

Surgical Treatment Palpable Disease

In this section, the surgical approach to the patient with a palpable tumor is addressed. A later section addresses the surgical approach to patients identified as RET mutation carriers by genetic screening. The surgical treatment of MTC is influenced by several factors. First, the biology and behavior of MTC are very different from those of differentiated thyroid cancer. MTC cells do not take up iodine, and radioactive iodine therapy is ineffective. Unlike differentiated thyroid cancer, MTC...

Lateral Approach for Parathyroid Exploration

The lateral approach for parathyroidectomy was first described by Feind.73 This approach involves dissection between the anterior border of the sternocleidomastoid muscle and the posterior border of the strap muscles.74 The omohyoid muscle is usually divided. Retraction of the sternocleidomastoid muscle and the carotid sheath laterally and the strap muscles medially exposes the lateral aspect of the thyroid gland, the tracheoesophageal groove, the recurrent laryngeal nerve, and the parathyroid...

Thyroid Storm

Thyroid storm is a poorly defined clinical syndrome. The synonyms include thyroid crisis, thyrotoxic storm, and thyrotoxic crisis. Thyroid surgery, once the most common pathogenesis of thyroid storm, has become a rare cause of this disorder. Even senior surgeons have seen only a few such patients. This is attributable to recognition of these patients, to administration of appropriate antithyroid drugs, and to the popularity of radioactive iodine therapy for treating patients with...

Lymphocytic Hashimotos Thyroiditis

Lymphocytic thyroiditis was first described in four female patients by Hashimoto in 1912 as struma lymphomatosa a transformation of thyroid tissue to lymphoid tissue.55 Subsequently, Roitt and colleagues demonstrated thyroid autoantibodies in patients with this disease.56 Chronic autoimmune thyroiditis has two different clinical manifestations an atrophic form and a goitrous form. The latter is also known as Hashimoto's thyroiditis57 and is the most common inflammatory disease of the thyroid....

Thyroid Stimulating Hormone Suppression and Thyroid Cancer

Controversy exists in thyroid cancer management about the extent of surgery, the use of 131I ablation therapy, the place of thyroglobulin assay in follow-up, and the role and level of TSH suppressant treatment. Further, there is debate about the degree of TSH dependence of differentiated thyroid carcinomas and the importance of other thyroid growth factors. Thyroid Growth Factors and Thyroid Carcinoma Thyroid tumors vary markedly in prognosis, and the natural history of differentiated tumors is...

Restoration of Differentiated Thyroid Function

DTCs of follicular cell origin (papillary and follicular cancers) are usually well differentiated and behave in a nonaggressive manner. However, some lose differentiated functions (dedifferentiation) and behave more aggressively. These cancers become refractory to thyroid-specific therapies that are based on differentiated thyroid function such as radioiodine therapy and thyrotropin (TSH)-suppressive therapy. Restoring differentiated functions in these tumors may not only slow tumor growth but...

Psychiatric Symptoms

Several authors have documented the common occurrence of nonspecific symptoms such as weakness, fatigue, and mental depression in PHPT.7,24,25 A wide spectrum of psychological symptoms ranging from mild personality changes to severe depression and psychosis has been described. These psychiatric symptoms develop in PHPT patients irrespective of the serum calcium level. Joborn and colleagues74 reported that hypercalcemic patients with asymptomatic PHPT (i.e., no kidney stones or osteitis fibrosa...

Preoperative Evaluation and Preparation

Adequate metabolic work-up and accurate radiologic evaluation of adrenal disease preoperatively are crucial. To determine whether an incidental adrenal mass in an asymptomatic patient is functional is obligatory, because virtually all functioning tumors should be excised and preoperative preparation is crucial for minimizing perioperative complications. In these instances, the evaluation should include a thorough history and physical examination and biochemical screening for occult...

Differentiated Thyroid Cancer of Follicular Cell Origin

The minimal test for determining the diagnosis of a thyroid nodule is fine-needle aspiration cytology with or without ultrasonography. Use of these two tests enables one to discriminate benign from malignant thyroid tumors in about 85 of patients. The remaining 15 of thyroid malignancies are follicular cancer, Hiirthle cell cancer, and some follicular variants of papillary thyroid cancer. Various imaging techniques are used for detecting regional and or distant metastasis and identifying local...

Anatomy of the Pancreas

Pancreatic Lymph Nodes

The pancreas is a mixed endocrine and exocrine gland that is located in the retroperitoneum within the epigastric and the left hypochondriac regions of the abdomen. It extends transversely across the posterior abdominal wall from the medial aspect of the descending portion of the duodenum, where it is fixed, to the hilum of the spleen, where it is relatively mobile. The stomach overlies the pancreas anteriorly. The pancreas lies across the inferior vena cava, portal vein, aorta, superior...

Incidentalomas of the Adrenal Gland and Adrenocortical Carcinoma

The frequent use of imaging procedures, especially ultrasonography and CT, results in the discovery of unsuspected adrenal masses. So-called incidentalomas or adrenalomas are the most common reason the clinician becomes concerned about the adrenal gland. Incidentalomas have been found in 0.6 to 4.3 of patients or at autopsy.4243 The major concern when evaluating a patient with an inciden-taloma is whether the tumor is functioning and whether it is benign or malignant (Fig. 66-9). Certain...

Addisons Disease and Acute Adrenal Hemorrhage

Adrenal insufficiency was first recognized in 1855, when Thomas Addison1 published the monograph, On the Constitutional and Local Effects of Disease of the Supraadrenal Capsules. He described 11 patients with general languor and debility, remarkable feebleness of the heart's action, irritability of the stomach, and a peculiar change of the color of the skin. The primary cause historically was adrenal destruction from tuberculosis. By the turn of the 20th century, surgery of the adrenal glands...

Myxedema Coma

Myxedema coma is another thyroid emergency. It is the extreme clinical manifestation of severe thyroid hormone deficiency. This syndrome is rare and is usually, but not exclusively, encountered in elderly women during the winter months. Most patients have long-standing untreated hypothyroidism or have arbitrarily discontinued thyroid hormone replacement. Although the prognosis for myxedema coma is markedly improved by the introduction of high-dose intravenous T4 treatment, it is still...

Rationale and Indications for Hemithyroidectomy

Before 1945, thyroid cancers were more aggressive tumors in most other parts of the world except Japan. This is probably because in Japan there was high iodine intake as a result of the consumption of seaweed and seafood. In the United States, the addition of iodine to table salt, bread, and water was begun in the 1920s and 1930s, and in European countries it was added after the end of World War II. Currently, most of the Western countries have become iodine sufficient, and some even iodine...

Graves Disease

Thyroid Stimulating Hormone Low Medicine

There are several subtle but distinct differences among patients with hyperthyroidism from Graves' and Plummer's diseases, as outlined in Table 7-1.10-13 Graves' disease is the most prevalent autoimmune disorder in the United States and the most common cause of hyperthyroidism. The chief risk factor for Graves' disease is female gender, in part due to modulation of the autoimmune response by estrogen. Other potential pr cipitants of the autoimmune process TABLE 7-1. Epidemiology of Graves' and...

Surgical Anatomy of the Thyroid and Parathyroid Glands

Ligament Berry

The normal adult thyroid gland weighs about 17 g. It is wrapped around the anterolateral portion of the upper tracheal rings and larynx. Each lobe occupies a bed between the trachea and the esophagus medially the carotid sheath posteriorly and the sternocleidomastoid, the sternohyoid, and the sternothyroid muscles laterally and anteriorly. If the sternothyroid and sternohyoid muscles are to be divided transversely, they must be transected high, at the cricoid level, to preserve their motor...

Evaluation of Patients Suspected Zollinger Ellison Syndrome

The introduction of pharmacologic agents that inhibit gastric acid hypersecretion now allows the luxury of a safe and unhurried evaluation of patients, including diagnostic testing and tumor localization before an operation. Before the introduction of the H2 receptor antagonists in 1978 and more recently the substituted benzimidazoles (omeprazole), most Z-E syndrome patients suffered complications of gastric acid hypersecretion before a surgeon was consulted.18,49'50 Urgent operations, not...

Diagnostic Procedures

Thyroid dysfunction is assessed by measurement of free thyroxine (T4), thyroid-stimulating hormone (TSH), and free triiodothyronine (T3), but, as previously stated, most patients with a thyroid nodule are euthyroid. A malignant nodule may occasionally be found in association with thyroiditis or Graves' disease, but it is rare for a malignant nodule to actually be the cause of hyperthyroidism. Thyroid antibody titers and thyroglobulin measurement add little to the clinical assessment....

Recommendations for the Use of Levothyroxine in Thyroid Cancer

The consensus recommendation currently is that TSH suppressive therapy should be given postoperatively to all patients with differentiated thyroid cancer. The exact definition of appropriate TSH suppression to suppress tumor growth adequately remains unclear. Studies with very large numbers and follow-up would be required to detect significant differences. The true efficacy of ablative 131I has never been established in a controlled clinical setting.228,229 In the postoperative setting in the...

Primary Hyperaldosteronism

Seventy-five percent of patients with primary hyperaldosteronism have benign adrenal adenomas, and 25 have idiopathic hyperplasia of the zona glomerulosa. Fewer than 1 have adrenocortical cancer. In patients with primary hyperaldosteronism, it is essential to determine whether it is caused by an adrenal adenoma or by hyperplasia because virtually all patients with adenomas benefit from surgical treatment (i.e., abatement of hypokalemia and lower blood pressure), but most patients with...

Modalities for Imaging the Adrenal Gland

Evaluation of a patient with an adrenal gland mass is founded on a thorough history and physical examination, followed by appropriate biochemical tests. After the diagnosis has been established, imaging procedures are used for localization and presurgical planning. Improvements of functional and anatomic imaging procedures allow reliable preoperative evaluation of virtually all adrenal masses. Computed tomography (CT) and magnetic resonance imaging (MRI) are the main modalities used to localize...

Thyroid

Clinical transplantation of thyroid tissue has not been widely utilized as thyroid hormone replacement therapy is safe, effective, and cost-effective in treating postoperative or disease-induced hypothyroidism in most patients. Autotransplantation of thyroid tissue has been performed mainly in two clinical scenarios, following resection of lingual thyroid and following thyroidectomy for multinodular goiter or Graves' disease. Numerous case reports documenting these transplants have appeared in...

Thyroxine and Ischemic Heart Disease

Clearly, T4 replacement is necessary to prevent the development of overt hypothyroidism in postsurgical patients. There is also an annual conversion rate of 3 from subclinical to clinical hypothyroidism after 131I therapy and slightly less than 1 per year after thyroidectomy. Post-thyroidectomy hypothyroidism is more likely in elderly patients and in those who have circulating thyroid autoantibodies.74,75 Myocardial infarction and angina are both recognized complications of levothyroxine...

Conclusion

Treatment by supraphysiologic dosing of levothyroxine is done to create adequate suppression of TSH without inducing clinical evidence of hyperthyroidism. The rationale is that TSH is one of the principal stimulants of thyroid growth. Its use is recommended in patients after a total thyroidectomy for differentiated carcinoma of the thyroid, particularly After total thyroidectomy (wait 4-6 weeks off T4 or 2 weeks off T3) T4, TSH, TG, pregnancy test, if female Anti-TG antibody status T4, TSH, TG,...

Operative Technique

Right Laparoscopic Adrenalectomy

Several laparoscopic approaches to the adrenal glands are recognized, including the following 1. Transabdominal lateral with the patient in the lateral decubitus position 2. Transabdominal anterior with the patient in the supine position 3. Retroperitoneal endoscopic adrenalectomy lateral or posterior Although the retroperitoneal approach is advocated by some authors,1417 the technique of choice by most surgeons performing laparoscopic adrenalectomy is the transabdominal lateral approach,...

Carbohydrate Metabolism

It has been frequently reported that PHPT patients have a higher risk of developing impaired glucose tolerance or diabetes mellitus.3'151618'99 Hyperinsulinemia in patients with PHPT suggested that these patients have a reduced insulin sensitivity and therefore impaired glucose tolerance.100105 Several studies have shown that up to 8 of patients with PHPT suffer from diabetes mellitus as compared with 2 of normocalcemic patients (Table 42-5).l6'l8'99'l06J07 Whether diabetes mellitus itself is...

Poma

VIPomas are generally located within the pancreas. They secrete excessive amounts of VIP, which causes a distinct syndrome. Patients have a very large volume diarrhea, severe hypokalemia with muscle weakness, hypercalcemia, and hypochlorhydria (Table 84-4). VIPoma typically occurs in adults. However, it has been reported in two children with severe diarrhea.42 It was originally called the Verner-Morrison syndrome42 because these two authors first described pancreatic cholera and the watery...

Pheochromocytoma

Pheochromocytoma Patients

In planning the localization of a pheochromocytoma, one should consider whether the tumor is sporadic or familial and whether the patient is an adult or child. Most pheochro-mocytomas are sporadic (85 ), and 15 are familial and occur in patients with multiple endocrine neoplasia (MEN) type 2, neurofibromatosis, or Sturge-Weber syndrome. Although 85 of the tumors are unilateral, bilateral pheochromocytomas are found in 50 of familial cases. About 15 of pheochromocytomas are malignant and are...

Overview of Glucose Metabolism

Physiology of Systemic Glucose Homeostasis Whole-body glucose homeostasis represents a balance between glucose supply and glucose disposal (or utilization). When the supply of glucose exceeds its disposal, blood glucose concentration rises when utilization exceeds supply, glucose levels fall. In normal individuals, this balance is intricately maintained so that blood glucose remains stable, typically between 60 and 140 mg dL, even in the setting of such disparate stressors as the ingestion of a...

Pathogenesis of Secondary Hyperparathyroidism

Stimulated by the description of enlarged parathyroid glands in uremic patients by Albright and colleagues,5 the Viennese pathologists Pappenheimer and Wilens6 were the first to attribute parathyroid hyperplasia to CRF. Since then, researchers have attempted to link decreased kidney functions with the biochemical, morphologic, and clinical manifestations of SHPT. The task has proved to be difficult because both the excretory and endocrine functions of the kidney are impaired in CRF. In...

Subtle Hyperparathyroidism

This chapter focuses on the physiology of calcium metabolism and the static and dynamic testing pertinent to the diagnosis of normocalcemic hyperparathyroidism in symptomatic patients with renal calculi or osteoporosis. An important group of patients with PHPT and recurrent renal calculi or severe osteopenia or osteoporosis has minimal, intermittent, or no elevation of the serum total calcium. The ionized calcium has been shown to be a more sensitive indicator of PHPT in this situation than...

Specific Complications

Facial, neck, or tracheal edema may be caused by decreased venous or lymphatic drainage from the operating field. It may interfere with inspiration and occurs especially if thyroidectomy is combined with bilateral lymphadenectomy, such as may be required in patients with medullary cancer.4 5 Severe edema in the case of isolated thyroid surgery is rare none of our patients needed treatment for this complication. It is more common in patients with neck dissections, and it can be prevented or...

Metastases to the Thyroid

The true incidence of metastases to the thyroid gland has not been clearly established. Autopsy studies have reported an incidence ranging from 2 to 25 .156159 In the study by Mortensen and colleagues, 4 of patients with metastatic neoplasms had secondary tumors of the thyroid gland.159 Silverberg and Vidone157 found the incidence to be much higher. In their study, they meticulously examined the thyroid and found the incidence of metastatic disease to the thyroid to be 24 in patients dying from...

Definition Advantages and Disadvantages of Hemithyroidectomy

Hemithyroidectomy can be used in a patient with low-risk papillary thyroid carcinoma that is macroscopically localized in one thyroid lobe. In this procedure, the whole involved lobe, the isthmus, and occasionally the medial portion of the contralateral lobe are resected. When the medial third of the contralateral lobe is included in the resection, the thyroid operation is referred to as subtotal thyroidectomy in the United States41 and in Japan.8,24 We include patients who had subtotal...

Papillary Thyroid Carcinoma Rationale for Total Thyroidectomy

Considerable controversy continues about whether all or part of the thyroid gland should be removed for patients with differentiated thyroid cancer of follicular cell origin (papillary, mixed papillary follicular, follicular, and Hurthle cell), because there are no controlled, prospective studies comparing the results of different methods of treatment (lobectomy, near-total thyroidectomy, or total thyroidectomy). Patients with these thyroid cancers also generally have a good prognosis, with an...

Intrathoracic Goiter

Intrathoracic Goiter

Mediastinal extension is common in large, bulky, multinodular goiters. Negative intrathoracic pressure and gravity facilitate the descent of an enlarged thyroid gland. Intrathoracic goiter is rarely (< 2 ) a purely mediastinal tumor developing in an embryonic ectopic remnant or in a fragment of goiter left behind after an initial thyroidectomy.32'33 Because lateral and medial expansion may be limited after previous surgery, recurrent goiters often have more mediastinal prolongation. Between 3...

Clinical Features of Hypercalcemic Crisis

A serum calcium level of 14.5 mg dL or higher must generally be considered a medical emergency, and most patients are symptomatic.9 Nevertheless, because relatively asymptomatic patients with a serum calcium of 20 mg dL, and even patients with levels below 14.5 mg dL, have presented in hypercalcemic crisis,23 the serum calcium level should not be the sole marker used to define hypercalcemic crisis.1 The severity of the hypercalcemia is usually proportional to the increase in PTH level.9 The...

Chondrocalcinosis and Pseudogout

Chondrocalcinosis is defined as the deposition of calcium salts in articular hyaline cartilage and fibrocartilage.131 This study showed that most patients were asymptomatic (21 of 71 30 ) and that only 4 (5.6 ) of 71 had intermittent attacks of pseudogout. Chondrocalcinosis and pseudogout are said to be sufficiently frequent (3.8 ) in hyperparathyroidism such that screening of such patients is warranted.132 Occasionally, pseudogout is the initial manifestation. It is characterized by arthritis...

Choice of Neck Dissection

Operations used to remove cervical lymph nodes vary from removing only grossly affected lymph nodes (node picking) to the classic radical neck dissection. Crile in 1906 developed the classic radical neck dissection for local control of head and neck cancers.73 Although this operation became the standard operation for most head and neck cancers, it is not used today for patients with thyroid cancer. Radical neck dissection is associated with disfiguring cosmetic and functional results, and...

Andreas Zielke MD

Department of Surgery, Endocrine Research Group, Philipps University, Marburg, Germany Adrenal Imaging Procedures Since the first edition of the Textbook of Endocrine Surgery there have been considerable changes in the clinical management of patients with endocrine surgical problems, as well as advances in basic science regarding endocrine neoplasms. Many colleagues have asked Drs. Duh and Clark whether another edition will be published because of numerous recent changes in endocrine surgery....

Follicular Carcinoma

Pathologic Features of Follicular Carcinoma Follicular carcinomas are the malignant counterparts to follicular adenoma. Follicular carcinomas come in two anatomic forms. The less aggressive but more difficult to diagnose variety is also called the angioinvasive encapsulated carcinoma or minimally invasive follicular carcinoma. These are usually small and seemingly encapsulated neoplasms of the thyroid gland that are grossly indistinguishable from follicular adenomas. Microscopically, however,...

Acute Suppurative Thyroiditis

Acute thyroiditis was first described by Bauchet in 1857 and accounted for approximately 0.1 of thyroid surgeries before the advent of antibiotic therapy.1 The thyroid gland has an innate resistance to infection due to its extensive blood and lymphatic supply, high iodide content, and fibrous capsule.2 Despite these protective mechanisms, acute thyroiditis may be caused by infectious agents that seed the thyroid gland (1) by the hematogenous or lymphatic route, (2) by direct spread from...

Rationale for Parathyroidectomy

There is good evidence that in about 80 of patients the clinical manifestations improve after successful parathyroidectomy.8'9,10'46'47 Thus, fatigue, exhaustion and weakness, polydipsia, polyuria and nocturia, bone and joint pain, constipation, nausea, and depression improve in some patients.8 I0'46'47 This is also true for associated conditions. In these patients, new kidney stones usually stop forming, osteoporosis stabilizes or improves, peptic ulcer disease often resolves, and pancreatitis...

Acute Adrenal Insufficiency Related to Bilateral Adrenal Hemorrhage

Veins Fragile Adrenal

Although historically bilateral adrenal hemorrhage is associated with meningococcemia in children (Waterhouse-Friderichsen syndrome), bilateral adrenal insufficiency occurs most commonly in adults in association with anticoagulant therapy. Clinical conditions producing coagulopathies such as thrombocytopenia, anticardiolipin antibody, and lupus anticoagulant also result in bilateral adrenal hemorrhage. Trauma, either directly or through the destruction of the blood supply to the adrenal, may...

Anatomy

Efferent Arteriole

The adrenals are retroperitoneal organs resting on either side on the crura of the diaphragm. They lie on each side of the vertebral column (T11-12), against the superomedial surface of the corresponding kidney, and are surrounded by a thin layer of loose areolar connective tissue and a thick fibrous capsule. This makes them easily separated from the superior pole of the kidney. The adrenal glands are held in position by numerous fibrous bands and vascular attachments. The adrenal glands are...

Treatment

Pituitary-Dependent Cushing's Syndrome The aim of treatment of Cushing's syndrome is to reduce Cortisol secretion to normal. Formerly, bilateral adrenalectomy was used for treating patients with pituitary-dependent Cushing's syndrome, but this treatment has long been replaced by direct pituitary surgical treatment. Patients with pituitary-dependent Cushing syndrome can be treated by (1) transsphenoidal microsurgery with tumor FIGURE 70-3. Responses of plasma corticotropin (ACTH) (pmol L) to...

Plummers Disease Toxic Multinodular Adenomatous Goiter

Adenomatous Goiter With Cystic Change

Toxic multinodular goiter was first described in 1913 by Dr. Henry Plummer (see Fig. 7-2), who believed that practically all adenomatous goiters would eventually become toxic given enough time. He noted that the average interval from first detection of the goiter to subsequent development of symptoms was 15 years.45,46 Nodular goiters (Fig. 7-8A) occur when hyperplasia of a small subset of follicular cells with abnormal growth potential occurs at multiple sites in the thyroid gland.10 In...

Iodine Deficiency

Iodine deficiency is a serious worldwide problem, particularly in Africa, China, southern Asia, and Europe. It is estimated that about 1 billion people are iodine deficient. About 20 million people have endemic goiter and 2 million people have endemic cretinism.53 To form adequate amounts of thyroid hormone, 100 to 150 ig day of iodine is needed.53 If iodine intake is less than 100 ig day, endemic goiter may develop. Further decrease in iodine intake of less than 25 ig day may cause endemic...

Painful de Quervains Thyroiditis

Painful thyroiditis is a transient inflammatory thyroid disorder that was first described by de Quervain in 190421 and is the most common cause of a painful thyroid gland. Other eponyms for this condition include granulomatous thyroiditis, subacute granulomatous thyroiditis, or pseudogranulomatous thyroiditis. Painful thyroiditis is thought to be viral in origin or result from a post-viral inflammatory response. This theory is supported by the following observations 1. The disorder is...

Approach to the Reoperative Patient

When the initial operation fails to return a patient to the nor-mocalcemic state or if hypercalcemia recurs after initial but temporary postoperative normocalcemia, the patient joins a special selective group of patients quite distinct from patients being considered for primary operation. It is extremely important that the diagnosis of primary HPT be reconfirmed rigorously. The confirmation of primary HPT should be based only on the stringent criterion of elevated, or inappropriately elevated,...