Chapter 24 patho

Hypoparathyroidism

symptoms associated with hypoparathyroidism are the result of insufficient PTH secretion and the resultant hypocalcemia. Muscle cramps Irritability Tetany Convulsion *Hypocalcemia causes a carpal spasm known as Trousseau's sign and facial muscle twitch called Chvostek's sign.

Hypothyroidism-1

Thyroid receptor antibodies Antithyroglobulin antibody Antithyroperoxidase antibody: hallmark of the disorder

Endocrine Gland Dysfunction Can Be Divided Into Two Categories:Be Divided Into Two Categories:

1-Hypofunction of an endocrine gland occurs when there is an inadequate amount of hormone secreted by the gland. 2-Hyperfunction of an endocrine gland occurs when there is an excessive amount of hormone secreted by the gland.

Endocrine Dysfunction Can Also Be Referred to as a Primary, Secondary, or Tertiary Disorder:

1-Primary disorder: dysfunction caused by the endocrine gland itself 2-Secondary disorder: dysfunction caused by abnormal pituitary activity 3-Tertiary disorder: dysfunction caused by a hypothalamic origin

Hypothalamic-Pituitary-Hormonal Axis

1-The hypothalamic portion of the brain secretes a releasing factor that stimulates the pituitary gland. 2-After the pituitary is stimulated, it releases a substance referred to as a tropic hormone that targets an endocrine organ. 3-The target endocrine organ then secretes a hormone that acts on the body and causes a physiological effect.

Graves' Disease (Hyperthyroidism)

Thyroid-stimulating antibodies bind to and activate thyrotropin receptors within the thyroid gland, causing the gland to enlarge and continually synthesize thyroid hormones.

Goiter

A goiter is an enlargement of the thyroid gland with or without symptoms of thyroid dysfunction. Excess pituitary TSH can stimulate enlargement of the thyroid gland and cause goiter formation. Low iodine levels cause low thyroid hormone manufacture, which the pituitary senses and then attempts to compensate for by increasing TSH, which incites goiter formation. Enlargement of the thyroid gland can also occur from goitrogens, which are foods or other substances that promote thyroid gland enlargement.

Most Common Cause of Cushing's Syndrome: Excessive Steroid UseSyndrome: Excessive Steroid Use

Administration of exogenous steroids can lead to the development of Cushing's syndrome. Cushing's syndrome symptoms can occur with the administration of oral, injected, or inhaled steroids.

Adrenal Insufficiency: Addison's Disease

Adrenal insufficiency is most commonly caused by autoimmune destruction of the adrenal gland. Symptoms: Weakness Hypotension Easy fatigue Inability to concentrate Emotional lability Anorexia Nausea Vomiting Hypoglycemia Electrolyte imbalances In women, there is loss of pubic and axillary hair and amenorrhea.

Characteristics Associated With Malignant Thyroid Nodule

Age younger than 20 years or older than 70 years Male sex Associated symptoms of dysphagia or dysphonia History of neck irradiation Firm, hard, or immobile nodule Presence of cervical lymphadenopathy

Example of Downregulation

An example of downregulation occurs when an individual takes an excessive, prolonged dose of glucocorticoid drugs (prednisone). The pituitary senses the high blood level of glucocorticoids; as a result, it does not need to secrete natural ACTH. There is no need to stimulate the adrenal gland because natural glucocorticoids are unnecessary; the body is receiving more than enough exogenous glucocorticoids. As a result, the adrenal gland downregulates its receptors and becomes less sensitive to ACTH stimulation. Adrenal atrophy can occur

Each ___________ has different risk factors for dysfunction, but major risk factors for endocrine disease include genetic predisposition, radiation exposure, medications, and pollutants.

endocrine gland

_________ is also called arginine vasopressin (AVP), and growth hormone is also called somatotropin

Antidiuretic hormone

Treatment of Hyperthyroidism

Antithyroid hormone medication propylthiouracil (PTU) Radioactive iodine* treatment Surgery Replacement thyroid hormone (levothyroxine) is needed for life.*Radioactive iodine is taken up by the gland and suppresses its activity.

The Endocrine Feedback System

As a result of pituitary stimulus, an endocrine gland secretes a specific hormone. After the hormone is secreted, the pituitary senses the level in the bloodstream. The pituitary interprets the level of hormone as normal, high, or low and then responds by either re-releasing the tropic hormone or ceasing tropic hormone release, thereby maintaining a normal hormone level.

Example of Negative Feedback

As cortisol levels in the bloodstream rise, the pituitary senses the increased level and shuts off the stimulus to the adrenal gland; this is an example of the endocrine negative feedback system.

Effects of High Cortisol Levels

Block the action of insulin -> glucose intolerance and hyperglycemia Inhibits bone formation and accelerates bone reabsorption -> osteopenia, osteoporosis Suppresses the inflammation and the formation of antibodies and inhibits white blood cells (WBCs) -> immunosuppression Elevates blood pressure -> hypertension (HTN)

SIADH Causes

Brain injury Brain surgery Cancer: paraneoplastic secretion of ADH

Empty Sella Syndrome

Cause of hypopituitarism; occurs when the meningeal membrane that surrounds the brain herniates into the sella turcica, a bony area where the pituitary gland sits in the brain. The herniation of this membrane flattens the pituitary against bone and pituitary insufficiency results. Empty sella syndrome can be caused by increased intracranial pressure, radiation, or trauma.

Excessive Growth Hormone of Hyperpituitarism

Children: gigantism: greater than 7 feet tall, large hands and feet, coarse facial features, hypogonadism, diabetes, and other endocrine problems Adults: acromegaly: excessivegrowth of jaw, hands, feet, enlarged tongue and organ enlargement, causing metabolic disorders

Hypothyroidism symptoms

Cold intolerance •Weight gain •Lethargy •Fatigue •Memory deficits •Poor attention span •Muscle cramps •Constipation •Decreased fertility •Puffy face •Hair loss •Brittle nails

The Adrenal Gland Consists of Two Parts: Cortex and MedullaParts: Cortex and MedullaCopyright

Cortex: secretes corticosteroids, also called glucocorticoids (cortisol), androgens (testosterone), and mineralocorticoids (aldosterone) Medulla: secretes epinephrine and norepinephrine

Diagnosis Hypopituitarism

Corticotropin stimulation test, which evaluates the hypothalamic-pituitary-adrenal axis, can distinguish hypopituitarism from primary adrenal insufficiency. This test measures the serum cortisol level before and after administration of ACTH. Normally, the cortisol level should rise 30 to 60 minutes after ACTH administration. A low cortisol level that fails to rise after ACTH administration is seen if there is adrenal gland etiology of the disorder.

Cushing's Syndrome

Cushing's syndrome can occur because of: ◦Adrenal adenoma ◦Adrenal carcinoma ◦Adrenal hyperplasia The Carney complex is a genetic disorder that includes hyperplasia of the adrenal gland, which causes Cushing's syndrome. McCune-Albright syndrome is a rare cause of hyperfunction of the adrenal glands that leads to Cushing's syndrome and precocious puberty. Cushing's syndrome can also be caused by secretion of ACTH from tumors of the lung or other cancers.

Cushing's Syndrome; Hyperadrenalism

Cushing's syndrome, also called hyperadrenalism or hypercorticolism, is an endocrine disorder caused by high levels of cortisol in the blood. There are two terms: Cushing's syndrome and Cushing's disease. Cushing's disease refers to a tumor of the pituitary gland that produces large amounts of ACTH, resulting in excessive cortisol production. Cushing's syndromeis hyperadrenalism that is caused by a hyperactive adrenal gland that secretes excessive cortisol. CUSHING'S SYNDROME is MORE COMMON.

Adrenal Mineralocorticoid Deficiency

Electrolyte imbalances occur from mineralocorticoid (aldosterone) deficiency. Aldosterone normally functions to stimulate the nephron to reabsorb sodium and water into the bloodstream and excrete potassium. In the absence of aldosterone, there is loss of sodium and water with retention of potassium. Patients experience hyponatremia, hyperkalemia, and dehydration.

Hormone Feedback System

Endocrine gland hormones include thyroxine, cortisol, epinephrine, parathyroid hormone, and antidiuretic hormone. These hormones keep the body in homeostatic balance and are kept in check by a unique endocrine feedback system. After the appropriate physiological action by the target organ is achieved, the endocrine system can shut off the effect.

Syndrome of Inappropriate ADH (SIADH)

Excessive ADH -> excessive water reabsorption at nephron -> blood Hypervolemia Concentrated urine Dilutional hyponatremia

Prolactinoma

Excessive PRL causes antiestrogenic and antiandrogenic effects. Female: menstrual abnormalities, amenorrhea, galactorrhea, vaginal dryness, and osteopenia occur. Males: hypogonadism, gynecomastia, decreased libido, erectile dysfunction, and infertility occur.

Hyperthyroidism

Excessive secretion of T3 and T4 Graves' disease: most common cause, an autoimmune stimulation of the thyroid gland (also called thyrotoxicosis). Other causes include thyroid adenoma, excessive pituitary TSH secretion, subacute thyroiditis, toxic multinodular goiter, excessive iodine ingestion (Jod-Basedow syndrome), and excessive thyroid hormone replacement.

Symptoms of DI

Frequent dilute urination Thirst Dehydration Confusion Disorientation Myoclonus Seizures Coma

Diagnosis of Hypothyroidism

High TSH level Low free T3 Low free T4 Antithyroglobulin (anti-Tg)Antithyroperoxidase (anti-TPO) antibodies In primary hypothyroidism, there is low hormone secretion by the thyroid gland, which constantly signals the pituitary to secrete TSH.

Endocrine Disease Can Be Divided Into Three Major Types of Into Three Major Types of Conditions: Conditions:

Hormone deficiency Hormone excess Hormone resistance

Treatment of Hypopituitarism

Hormone replacement and surgical excision of tumor, if present, are the treatment measures.

Treatments of Endocrine Disorders

Hormone replacement therapy is used with hormone deficiency. Dosage schedules attempt to mimic physiological hormone production. Suppression of hormone overproduction is accomplished medically or surgically.

Hypopituitarism

Hypopituitarism, also known as pituitary insufficiency, is the hyposecretion of one or more of the pituitary hormones.

Adrenal Gland

Hypothalamic corticotropin-releasing factor (CRF) -> pituitary adrenocorticotropic hormone (ACTH) ->stimulates the adrenal gland. Disorders of the adrenal gland mainly consist of adrenal overactivity (Cushing's syndrome) or adrenal insufficiency (Addison's disease).

Diagnosis of Endocrine Disorders

Immunoassays or blood levels of hormones are the most important diagnostic tools in endocrine disorders. Urinary hormone levels are useful for some conditions. Urinary collection over 24 hours often can provide useful information in the analysis of metabolic function. Suppression tests CT scan/MRI Ultrasound

Stress Requires Steroid Administration

In adrenal insufficiency, parenteral steroids should be administered in times of major stress, trauma, or surgery and during any major procedure.

Hypopituitarism-

In hypopituitarism, tropic hormone production is reduced and, in turn, target gland hormone production is decreased. Normally low levels of target gland hormone feedback to the pituitary gland increases tropic hormone production. However, in hypopituitarism, the pituitary gland is dysfunctional and the response is absent or inadequate. In adults, a pituitary adenoma is the most common cause of hypopituitarism. A pituitary adenoma is a benign, epithelial neoplasm that can compress pituitary tissue or interfere with the delivery of hypothalamic hormones to the pituitary gland. Another intracranial tumor associated with hypopituitarism is a craniopharyngioma. This benign neoplasm can develop close to the pituitary gland or in the pituitary stalk. It causes pressure on the pituitary gland, which renders the gland nonfunctional.

Various Treatments for Hyperpituitarism

In prolactinoma, bromocriptine blocks secretion of prolactin and can shrink tumors. Transsphenoidal surgery may be required with medication. Adrenal enzyme inhibitors, such as ketoconazole, are block formations of adrenal hormones. In somatotropin-secreting tumors, octreotide suppresses excessive growth-hormone secretion. A growth hormone receptor antagonist, Pegvisomant, has shown some success.

Hypothyroidism

Insufficient levels of the thyroid hormones T3 and T4 Hashimoto's thyroiditis, an autoimmune disorder, is the most common cause of hypothyroidism.

_____ pituitary tumors can compress brain tissue and cause headache, dizziness, and visual disturbances because of proximity to the optic nerve chiasm.

Large

Diagnosis of Graves' Disease

Low TSH High T3 High T4 Antithyroglobulin Antithyrotropin receptor antibody Ultrasound with color-Doppler evaluation Radioactive iodine scanning and measurements of iodine uptakeIn Graves' disease, the radioactive iodine uptake is increased and the uptake is diffusely distributed over the entire gland.

Autoimmune Cause for Endocrine Gland Dysfunction

Many endocrine disorders occur because of autoimmunity, which itself occurs when the body manufactures antibodies against its own tissues. The cause for these autoantibodies is unknown, but they trigger inflammation in organs they target. In the endocrine system, autoimmunity can cause either hypofunction or hyperfunction of the gland. Another common cause of endocrine dysfunction is neoplasia, or tumor formation. Tumors can be a source of excess hormones and cause hyperfunction of the gland. They can also interfere with hormone production and cause hypofunction. A pituitary tumor can cause dysfunction in multiple organs because of the wide array of endocrine glands under its control.

Thyroid Nodule

Most thyroid nodules are asymptomatic, but they can cause hypothyroidism or hyperthyroidism. A single thyroid nodule is associated with an increased risk of malignancy, whereas multiple nodules are often benign.

Signs and Symptoms of Hypopituitarism-

Neonate and infant: dwarfism, developmental delay, various visual and neurological symptoms, seizure disorder, and congenital malformations. Adults: weakness, weight loss, hypotension caused by adrenal insufficiency or weight gain, sluggishness, and depression caused by hypothyroidism. Excessive urination and dehydration occur.

Graves' Disease (Hyperthyroidism)- symptoms

Nervousness Insomnia Sensitivity to heat Weight loss Gland is usually enlarged and palpable. An audible bruit may be heard because of high glandular blood flow. Atrial fibrillation Exophthalmos

Thyrotoxic Crisis (Thyroid Storm)

Overwhelming release of thyroid hormones that exerts an intense stimulus on the metabolism. This is a life-threatening condition most commonly precipitated by surgery, trauma, or infection.

Hyperpituitarism

Pituitary adenoma is the most common cause of hyperpituitarism. The adenoma can produce ACTH, TSH, or growth hormone (GH). Prolactinoma is a specific type of pituitary adenoma that produces PRL.

Upregulation and Downregulation of Endocrine Receptors

Pituitary hormones act on receptors located on endocrine glands to secrete hormones. The reactions of the receptors on endocrine glands vary depending on the amount of stimulation by these pituitary hormones. For instance, prolonged, excessive stimulation of an endocrine gland often results in receptor insensitivity and may decrease its number of receptors in a process known as a downregulation of receptors. Conversely, upregulation of receptors is an increase in the number of receptors and their sensitivity. The most common reason for upregulation is a reduction in the receptor stimulation by hormones.

Causes of Hypopituitary Function

Pituitary tumor Complications following brain surgery Radiation of a brain tumor Trauma Ischemia Infarction Hemorrhage Sheehan's syndrome is pituitary ischemia and infarction that develops after childbirth because of severe hemorrhage. Empty sella syndrome, a condition caused by compression of the pituitary gland by brain tissue herniation, is also a cause of hypopituitarism. Panhypopituitarism, a rare disorder, is the complete loss of all the pituitary hormones.

Diabetes Insipidus (DI) vs. Diabetes Mellitus (DM)

Polyuria and dehydration occur in both diabetes mellitus and diabetes insipidus. It is important to measure serum glucose to differentiate DM from DI. Serum glucose is elevated in DM, but not in DI.

Diabetes Insipidus (DI)

Posterior pituitary* hypopituitarism; lack of antidiuretic hormone (ADH) Categories of disease: 1- central DI caused by a lack of secretion of ADH from the posterior pituitary 2- nephrogenic DI when the kidney fails to respond to ADH * postpituitary; also called neurohypophysis

Hypothyroidism Affects All Body Organs:

Raises cholesterol; hyperlipidemia Raises carotene levels (yellows skin) Causes anemia Decreases filtration by kidney Can cause hoarse voice

Treatment of Hypothyroidism

Replacement hormone therapy with levothyroxine Surgical intervention if necessary

Diagnosis of Cushing's Syndrome-

Salivary cortisol level measurement is another laboratory test for Cushing's syndrome

Sheehan's Syndrome

Sheehan's syndrome is ischemia or infarction of the pituitary which can occur after childbirth because of severe hemorrhage. Hypopituitarism results. Women who suffer from Sheehan's syndrome develop deficiency of ACTH, TSH, FSH, LH, ADH, and PRL, which results in adrenal insufficiency, hypothyroidism, amenorrhea, diabetes insipidus (DI), and inadequate lactation.

Paraneoplastic Disorders

Some cancers cause development of paraneoplastic disorders. These are disorders where, for an unknown reason, the cancer cells have the ability to secrete an endocrine hormone; for example, specific types of lung cancer often secrete ACTH.

_______, which is common in elderly individuals, can cause subtle neuropsychiatric problems such as disorientation, depression, and pseudodementia.

Subclinical hypothyroidism

Pituitary Apoplexy

Sudden destruction of the pituitary tissue caused by infarction or hemorrhage into the gland. Traumatic brain injury is the most common cause, but it can occur in patients with DM, pregnancy, sickle cell anemia, anticoagulation, or increased intracranial pressure.

Treatment of Cushing's Syndrome

Surgery is used to remove the source of hyperadrenalism Ketaconazole can suppress cortisol.

Hyperparathyroidism

Symptoms of hyperparathyroidism are caused by excessive secretion of PTH with resulting hypercalcemia and bone breakdown. Muscle weakness Poor concentration Neuropathies Hypertension Kidney stones Metabolic acidosis Osteopenia Pathological fractures Constipation Depression, confusion, or subtle cognitive deficits

Pituitary

The anterior pituitary secretes growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). The hypothalamus synthesizes antidiuretic hormone (ADH) and oxytocin (OXY), which are stored and released by the posterior pituitary.

Diagnosis of Cushing's Syndrome

The dexamethasone suppression test The test requires administration of 1 mg of dexamethasone at 11 p.m. with subsequent measurement of cortisol level at 8 a.m. In healthy individuals, the serum cortisol level should be suppressed. In Cushing's syndrome, there is no suppression of cortisol and a high level is present.

Example of Endocrine Feedback

The hypothalamus secretes corticotropin-releasing factor (CRF), which stimulates the pituitary gland. The pituitary gland secretes adrenocorticotropic hormone (ACTH), which, in turn, stimulates the adrenal gland to secrete the hormone cortisol

Pathophysiology of DI

The nephron does not perform antidiuresis, meaning that the nephron does not reabsorb waterfrom the tubule fluid. The body loses high amounts of water in the urine, causing polyuria and highly dilute urine. The bloodstream loses water, which concentrates its sodium content, causing hypernatremia and dehydration.

Parathyroid Gland

The parathyroid glands are four pea-sized glands nestled within the thyroid tissue of the neck. The glands produce and secrete parathyroid hormone (PTH) in response to hypocalcemia and break down bone to re-establish normal calcium in the blood.

Treatment of Adrenal Insufficiency

The patient needs replacement doses of glucocorticoid and mineralocorticoid daily. This is commonly achieved with 100 mg or more of hydrocortisone per day and 9-alpha-fludrocortisone in doses of 0.05 to 0.10 mg per day or every other day.

Pineal Gland Dysfunction

The pineal gland produces melatonin with the phases of the light-dark cycle. A pineal tumor can compress parts of the brain that drain cerebrospinal fluid (CSF), causing a buildup of pressure called hydrocephalus. Symptoms include headache, nausea and vomiting, seizures, memory disturbances, and visual changes.

The Hypothalamic-Pituitary Connection

The pituitary, also called the hypophysis, has two distinct sections: 1-anterior pituitary called the adenohypophysis 2-posterior pituitary referred to as neurohypophysis The hypothalamus and pituitary gland are in communication with each other via specialized neurovascular tissue called the hypothalamus-hypophyseal portal system.

Posterior Pituitary Hormones

The posterior pituitary does not produce its own hormones; it stores hormones. The hypothalamus produces antidiuretic hormone (ADH) (also referred to as arginine vasopressin [AVP]) and oxytocin (OXT). These two hormones are released into the hypothalamic-hypophyseal tract to the posterior pituitary, where they are stored. From the posterior pituitary they are released into the circulation when needed.

Diagnosis of Adrenal Insufficiency

The rapid adrenocorticotropic hormone (ACTH) test is used to diagnose adrenal insufficiency. The patient is administered ACTH and there should be a rise in blood cortisol level to 2 to 5 times its basal level within 15 to 30 minutes. If this occurs, adrenal cortex function is normal; if there is no rise in cortisol, adrenal insufficiency is diagnosed.

Signs and Symptoms of Hypopituitarism

The signs and symptoms of pituitary insufficiency are dependent upon which tropic hormones are not secreted. The most serious concerns are adrenal insufficiency, hypothyroidism, and diabetes insipidus (DI) (DI = lack of ADH).

Thyroid

The thyroid gland is a butterfly-shaped gland located in the neck that secretes triiodothyronine (T3) and thyroxine (T4). Thyroxine is the regulator of body metabolism that influences almost every body system. Iodine is a necessary component in the synthesis of thyroid hormone. Thyroid problems are more likely in women than men.

Treatment of DI

The treatment for central DI is administration of ADH. Surgical treatment of some pituitary causes of DI may be required. Supportive treatment measures and the use of nonsteroidal anti-inflammatory agents (NSAIDs) are used for the patient with nephrogenic DI. Indomethacin, an NSAID, has been successful in nephrogenic DI, though the mechanism is unclear.

Multiple Endocrine Neoplasia

There are several syndromes of multiple endocrine neoplasia (MEN), but the most common is called MEN 1. MEN 1 is caused by a defective tumor suppressor gene at 11q13 that allows tumor growth in several different endocrine glands. The endocrine glands most frequently involved are the parathyroid gland, pituitary gland, and pancreas.

Anterior Pituitary Hormones

Thyrotropin, or thyroid-stimulating hormone (TSH) Gonadotropins; follicle-stimulating hormone (FSH) and luteinizing hormone (LH) Somatotropin or growth hormone (GH) Corticotropin, or adrenocorticotropic hormone (ACTH) Prolactin

Pheochromocytoma

Tumor of the adrenal medulla that secretes norepinephrine and epinephrine, causing excessive sympathetic stimulation. Symptoms: severe hypertension, tremors, increased cardiac contractility, cardiac arrhythmias, and elevated heart rate. Diagnosis: 24-hour urine that is analyzed for an excessive amount of catecholamine metabolites.

Unique Effect in Adrenal Insufficiency

Uniquely, when ACTH is excessively secreted, melanocyte-stimulating hormone (MSH) is triggered as well because both ACTH and MSH have the same precursor. The adrenal gland is provoked, and MSH stimulates melanocytes. The stimulated melanocytes give patients a tanned appearance.

Technetium Scan Using a Radioactive Isotope

Used to differentiate malignant from benign thyroid nodules The scan identifies nodules as hot, warm, or cold according to their uptake of radioactive isotope. A hot nodule is a hyperfunctioning tumor, a warmnodule indicates normal tissue, and a cold nodule is hypofunctional tissue, which is sometimes malignant

Cushingoid Signs and Symptoms

Weight gain Redistribution of body fat to the face, trunk, and abdomen Rose-colored, puffy face called "moon facies" Extra subcutaneous fat in the cervicothoracic area called "buffalo hump" Increase in the waist-to-hip circumference ratio, with apple-shaped fat distribution Increased subcutaneous fat deposits, particularly in the abdomen, lead to purple stretch marks called striae. Easy bruising and poor wound healing Women demonstrate hirsutism, male pattern hair growth.

Administration of Steroids

When administering corticosteroids to patients, the smallest dose should be used for a short period of time. Long-term corticosteroid administration can cause decreased secretion of natural cortisol and atrophy of the adrenal gland.

Prolonged Corticosteroid Use

When patients are administered prolonged corticosteroid treatment beyond 4 to 5 weeks, there is negative feedback suppression of CRH and ACTH. As a result, the adrenal gland can downregulate its receptors and undergo glandular atrophy. With atrophy, there is a decreased ability to secrete natural cortisol. The patient will then develop symptoms of adrenal insufficiency; in the case of high stress, surgery, or infection, the patient may develop adrenal crisis

Endocrine Dysfunction

When the endocrine system dysfunctions, there is an imbalance of hormones that can cause hyperfunction or hypofunction of the target organs. Dysfunction can occur at the hypothalamus, pituitary, or endocrine gland itself.

Exophthalmos

Wide-eyed stare associated with increased sympathetic tone and infiltration of the extraocular area with lymphocytes and mucopolysaccharides. Periorbital edema and bulging of the eyes termed Graves' ophthalmopathy. Women are more often affected with Graves' ophthalmopathy than men.

In the _________, severe hypothyroidism or hyperthyroidism can cause myxedema, also referred to as pretibial dermopathy, nonpitting edema, and thickened leg skin.

adult