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135 Cards in this Set
- Front
- Back
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MEN I (Wermer's Syndrome)
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Chromosomal deletion 11q12-13; (1) Parathyroid hyperplasia; (2) Pancreatic [and duodenal] islet cell tumors; (3) Pituitary adenomas [prolactinoma is most common]
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What are the three P's?
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Pituitary, Parathyroid, and Pancreas --> MEN I
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Men IIA (Sipple's Syndrome)
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RET oncogene mutation on chromosome 10q11.2; missense mutations on chromosome 1; (1) Medullary thyroid carcinoma; (2) Pheochromocytoma - majority are bilateral; (3) Parathyroid hyerplasia
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MEN IIB
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(1) Mucosal nueroma may be earliest sign (100%) - hypertrophied lips, thickened eyelids, Marfanoid habitus - skeletal abnormalities of spine, kyphosis/pectus excavatum; (2) Medullary thyroid carcinoma; (3) Pheochromocytoma
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MEN IIA and IIB
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Both consist of medullary thyroid carcinoma and pheochromocytoma. The additional components differ: Another P in MEN IIA (think PARATHYROID) and M in MEN IIB (think MUCOSAL neuromas and MARFANOID habitus)
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Medullary carcinoma of thyroid
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Can produce the rare tumor marker calcitonin that can be converted to AMYLOID!
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Thyroglassal duct cyst
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Persistence of the thyroid-pharynx connection may occur via a sinus or cyst, called a thyroglossal duct cyst. These cysts present as midline neck masses that move with swallowing and are usually seen in children or adolescents. They should be surgically excised because of the risk of infection. They are the MOST COMMON congenital anomaly and are easier to see when tongue is sticking out. Tx: excision of duct remnant and central portion of hyoid bone (Sistrunk's operation)
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Development of thyroid gland
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The thyroid develops at the base of the tongue between the fi rst pair of pharyngeal pouches, in an area called the foramen cecum. The thyroid descends down midline to final location overlying thyroid cartilage.
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Pyramidal lobe of thyroid
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Seen in 50-80% of population; represents remnant of distal thyroglossal tract. Extends superiorly from median isthmus
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Thyroid lymphatics
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Ultimately drain to internal jugular nodes. Intraglandular lymphatics connect both lobes explaining the relatively high frequency of multifocal tumors in the thyroid.
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What structure is often damaged during thyroid surgery, resulting in ipsilateral vocal cord paralysis and hoarseness?
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The recurrent laryngeal nerve (RLN). It innervates all the intrinsic muscles of the larynx, except the cricothyroid (supplied by the superior laryngeal nerve), and provides sensory innervation to the mucous membranes below the vocal cord.
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How long are thyroid stores kept in our body?
|
Thyroid follicles store enough hormone to last 2–3 months. Thus, there is no need to worry about your postop hypothyroid patients who are NPO for several days. They can resume taking their levothyroxine when they begin a PO diet.
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Causes of HYPERthyroidism
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(1) Graves' disease; (2) Toxic nodular goiter; (3) Toxic thyroid adenoma; (4) Subacute thyroiditis; (5) Functional metastatic thyroid cancer; (6) Struma ovarii [abnormal thyroid tissue in ovary]
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MEN I (Wermer's Syndrome)
|
Chromosomal deletion 11q12-13; (1) Parathyroid hyperplasia; (2) Pancreatic [and duodenal] islet cell tumors; (3) Pituitary adenomas [prolactinoma is most common]
|
|
|
What are the three P's?
|
Pituitary, Parathyroid, and Pancreas --> MEN I
|
|
|
Men IIA (Sipple's Syndrome)
|
RET oncogene mutation on chromosome 10q11.2; missense mutations on chromosome 1; (1) Medullary thyroid carcinoma; (2) Pheochromocytoma - majority are bilateral; (3) Parathyroid hyerplasia
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MEN IIB
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(1) Mucosal nueroma may be earliest sign (100%) - hypertrophied lips, thickened eyelids, Marfanoid habitus - skeletal abnormalities of spine, kyphosis/pectus excavatum; (2) Medullary thyroid carcinoma; (3) Pheochromocytoma
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MEN IIA and IIB
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Both consist of medullary thyroid carcinoma and pheochromocytoma. The additional components differ: Another P in MEN IIA (think PARATHYROID) and M in MEN IIB (think MUCOSAL neuromas and MARFANOID habitus)
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Medullary carcinoma of thyroid
|
Can produce the rare tumor marker calcitonin that can be converted to AMYLOID!
|
|
|
Thyroglassal duct cyst
|
"Persistence of the thyroid-pharynx connection may occur via a sinus or cyst, called a thyroglossal duct cyst. These cysts present as midline neck masses that
|
|
|
Development of thyroid gland
|
The thyroid develops at the base of the tongue between the fi rst pair of pharyngeal pouches, in an area called the foramen cecum. The thyroid descends down midline to final location overlying thyroid cartilage.
|
|
|
Pyramidal lobe of thyroid
|
Seen in 50-80% of population; represents remnant of distal thyroglossal tract. Extends superiorly from median isthmus
|
|
|
Thyroid lymphatics
|
Ultimately drain to internal jugular nodes. Intraglandular lymphatics connect both lobes explaining the relatively high frequency of multifocal tumors in the thyroid.
|
|
|
What structure is often damaged during thyroid surgery, resulting in ipsilateral vocal cord paralysis and hoarseness?
|
The recurrent laryngeal nerve (RLN). It innervates all the intrinsic muscles of the larynx, except the cricothyroid (supplied by the superior laryngeal nerve), and provides sensory innervation to the mucous membranes below the vocal cord.
|
|
|
How long are thyroid stores kept in our body?
|
Thyroid follicles store enough hormone to last 2–3 months. Thus, there is no need to worry about your postop hypothyroid patients who are NPO for several days. They can resume taking their levothyroxine when they begin a PO diet.
|
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Causes of HYPERthyroidism
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(1) Graves' disease; (2) Toxic nodular goiter; (3) Toxic thyroid adenoma; (4) Subacute thyroiditis; (5) Functional metastatic thyroid cancer; (6) Struma ovarii [abnormal thyroid tissue in ovary]
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Patient with Atrial F ibrillation refractory to medical treatment - why?
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Likely have hyperthyroidism - control with methimazole or PTU! 10% of patients with AFib are refractory to medical treatment until the hyperthyroidism is well controlled
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Graves' Disease
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MCC of hyperthyroidism in US; Mechanism: autoimmune disorder causes excess of thyroid hormone to be produced due to presence of thyroid-stimulating immunoglobulins that stimulates production of TSH. Women 6:1; onset age 20-40. Increased risk of other autoimmune disorders
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S&S of Graves' disease
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(1) Nervousness, increased sweating, tachycardia, goiter, pretibial myxedema, tremor; (2) Heat intolerance, palpitations, fatigue, weight loss, dyspnea, weakness, increased appetite, exophthalmos, thyroid bruit; (3) Amenorrhea, decreased libido, fertility
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Diagnosis of Graves' disease
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LABS: TFTs are increased with decreased TSH; RAIU shows diffusely increased uptake
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Treatment of Graves' disease
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(1) Antithyroid drugs ; (2) Radioiodide ablation; (3) Subtotal or total thyoidectomy;
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Medical therapy for Graves' disease
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(1) Beta-blockers provide symptomatic relief; (2) Antithyroid drugs: methimazole, PTU inhibit hormone production and peripheral conversion of T4-->T3; (3) Potassium iodide reduces hormone production (via Wolff-Chaikoff effect) used to shrink gland prior to surgical excision; (4) High recurrence rate with medical therapy; (5) Check TFTs after any treatment to determine if patient is euthyroid or requires hormone replacement
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MEN I (Wermer's Syndrome)
|
Chromosomal deletion 11q12-13; (1) Parathyroid hyperplasia; (2) Pancreatic [and duodenal] islet cell tumors; (3) Pituitary adenomas [prolactinoma is most common]
|
|
|
What are the three P's?
|
Pituitary, Parathyroid, and Pancreas --> MEN I
|
|
|
Men IIA (Sipple's Syndrome)
|
RET oncogene mutation on chromosome 10q11.2; missense mutations on chromosome 1; (1) Medullary thyroid carcinoma; (2) Pheochromocytoma - majority are bilateral; (3) Parathyroid hyerplasia
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MEN IIB
|
(1) Mucosal nueroma may be earliest sign (100%) - hypertrophied lips, thickened eyelids, Marfanoid habitus - skeletal abnormalities of spine, kyphosis/pectus excavatum; (2) Medullary thyroid carcinoma; (3) Pheochromocytoma
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|
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MEN IIA and IIB
|
Both consist of medullary thyroid carcinoma and pheochromocytoma. The additional components differ: Another P in MEN IIA (think PARATHYROID) and M in MEN IIB (think MUCOSAL neuromas and MARFANOID habitus)
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Medullary carcinoma of thyroid
|
Can produce the rare tumor marker calcitonin that can be converted to AMYLOID!
|
|
|
Thyroglassal duct cyst
|
Persistence of the thyroid-pharynx connection may occur via a sinus or cyst, called a thyroglossal duct cyst. These cysts present most often as asymptomatic midline neck masses that are palpable and located below the level of the hyoid bone. The mass moves during swallowing or on protrusion of the tongue because of its attachment to the tongue via the tract of thyroid descent. Some patients will have neck or throat pain, or dysphagia.
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Development of thyroid gland
|
The thyroid develops at the base of the tongue between the fi rst pair of pharyngeal pouches, in an area called the foramen cecum. The thyroid descends down midline to final location overlying thyroid cartilage.
|
|
|
Pyramidal lobe of thyroid
|
Seen in 50-80% of population; represents remnant of distal thyroglossal tract. Extends superiorly from median isthmus
|
|
|
Thyroid lymphatics
|
Ultimately drain to internal jugular nodes. Intraglandular lymphatics connect both lobes explaining the relatively high frequency of multifocal tumors in the thyroid.
|
|
|
What structure is often damaged during thyroid surgery, resulting in ipsilateral vocal cord paralysis and hoarseness?
|
The recurrent laryngeal nerve (RLN). It innervates all the intrinsic muscles of the larynx, except the cricothyroid (supplied by the superior laryngeal nerve), and provides sensory innervation to the mucous membranes below the vocal cord.
|
|
|
How long are thyroid stores kept in our body?
|
Thyroid follicles store enough hormone to last 2–3 months. Thus, there is no need to worry about your postop hypothyroid patients who are NPO for several days. They can resume taking their levothyroxine when they begin a PO diet.
|
|
|
Causes of HYPERthyroidism
|
(1) Graves' disease; (2) Toxic nodular goiter; (3) Toxic thyroid adenoma; (4) Subacute thyroiditis; (5) Functional metastatic thyroid cancer; (6) Struma ovarii [abnormal thyroid tissue in ovary]
|
|
|
Patient with Atrial F ibrillation refractory to medical treatment - why?
|
Likely have hyperthyroidism - control with methimazole or PTU! 10% of patients with AFib are refractory to medical treatment until the hyperthyroidism is well controlled
|
|
|
Graves' Disease
|
MCC of hyperthyroidism in US; Mechanism: autoimmune disorder causes excess of thyroid hormone to be produced due to presence of thyroid-stimulating immunoglobulins that stimulates production of TSH. Women 6:1; onset age 20-40. Increased risk of other autoimmune disorders
|
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S&S of Graves' disease
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(1) Nervousness, increased sweating, tachycardia, goiter, pretibial myxedema, tremor; (2) Heat intolerance, palpitations, fatigue, weight loss, dyspnea, weakness, increased appetite, exophthalmos, thyroid bruit; (3) Amenorrhea, decreased libido, fertility
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Diagnosis of Graves' disease
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LABS: TFTs are increased with decreased TSH; RAIU shows diffusely increased uptake
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Treatment of Graves' disease
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(1) Antithyroid drugs ; (2) Radioiodide ablation; (3) Subtotal or total thyoidectomy;
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Medical therapy for Graves' disease
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(1) Beta-blockers provide symptomatic relief; (2) Antithyroid drugs: methimazole, PTU inhibit hormone production and peripheral conversion of T4-->T3; (3) Potassium iodide reduces hormone production (via Wolff-Chaikoff effect) used to shrink gland prior to surgical excision; (4) High recurrence rate with medical therapy; (5) Check TFTs after any treatment to determine if patient is euthyroid or requires hormone replacement
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Toxic Nodular Goiter (Plummer's Disease)
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(1) Causes hyperthyroidism, but without the extrathyroidal symptoms; (2) Tx is surgical since medical therapy and radioablation have high failure rate; (3) Solitary nodule: lobectomy, multinodular goiter: subtotal thyroidectomy
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Thyroid Storm (Thyrotoxicosis)
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Life-threatening extreme exacerbation of hyperthyroidism precipitated by surgery on an inadequately prepared patient (i.e., incomplete beta-blockade and noneuthyroid patients), infection, labor, iodide administration, or recent radioablation; (1) Patients present with fever, tachycardia, muscle stiffness or tremor, AMS; (2) 50% of patients with thyroid storm develop congestive heart failure; (3) 20-40% mortality rate; (4) Treat with fluids, antithyroid meds, beta blockers, steroids, potassium iodide, cooling blanket
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Risks of thyroid surgery
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(1) Recurrent laryngeal nerve injury; (2) Hypoparathyroidism; (3) Persistent hyperthyroidism [with subtotal thyroidectomy]
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Hypothyroidism
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Autoimmune thyroiditis; may be either (1) Iatrogenic as s/p thyroidectomy, s/p radioablation, or secondary to antithyroid medications; (2) Iodine deficiency
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S&S of hypothyroidism
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Differ, depending on age of diagnosis: (1) Infants/peds: characteristic Down's-like facies, FTT, mental retardation; (2) Adolescents/adults: most are female, bradycardia, decreased CO, hypotension, SOB secondary to effusions; (3) Presentation includes: fatigue, wt loss, cold intolerance, constipation, menorrhagia, decreased libido/fertility
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Diagnosis of hypothyroidism
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LABS: decreased T4, T3; Increased TSH in primary hypothyroidism, decreased in secondary hypothyroidism; Thyroid autoantibodies present in autoimmune thyroiditis
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Treatment of hypothyroidism
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Thyroxine PO or IV emergently if patient presents in myxedema coma
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Acute thyroiditis
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(1) Risk factors: female sex, goiter, thyroglossal duct; (2) S&S: unilater neck pain/fever, euthyroid state, dysphagia; (3) Treatment: antibiotics and surgical drainage
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What causes acute suppurative thyroiditis
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Infectious etiology: S. pyogenes, S. aureus, S. pneumoniae; the bacteria usually spread through lymphatics from a nearby locus of infection
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Subacute (DeQuervain's) Thyroiditis
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(1) ETIOLOGY: post-viral URI; (2) RISK FACTOR: female sex; (3) S&S: fatigue, depression, neck pain, fever, unilateral swelling of thyroid with overlying erythema, firm and tender thyroid, transient hyperthyroidism usually preceding hypothyroid phase; (4) TREATMENT: NSAIDs, disease is self-limitied
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Chronic (Hashimoto's Thyroiditis)
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(1) ETIOLOGY: autoimmune; (2) RISK FACTORS: Down's, Turner', familial Alzheimer's, history of radiation therapy as child; (3) S&S: painless enlargement of thyroid, neck tightness, presence of other autoimmune diseases; (4) DIAGNOSIS: anti-microsomal antibodies targeting thyroid cells, thyroid hormone, T3, T4, TSH receptor
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Pathology seen in Hashimoto's Thyroiditis
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Firm, symmetrical, enlargement; follicular and Hürthle cell hyperplasia; lymphocytic and plasma cell infiltrates.
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Riedel's Thyroiditis
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Fibrosis that replaces both lobes and isthmus of the thyroid. RISK FACTORS: other fibrosing conditions, like retroperitoneal fibrosis, sclerosing cholangitis. S&S:usually euthyroid; neck pain, possible airway compromise, firm, nontender, enlarged thyroid
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Pathology seen in Riedel's Thyroiditis
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Dense, invasive fibrosis of both lobes and isthmus; may also involve adjacent structures
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Treatment for Riedel's thyroiditis
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(1) With airway compromise: isthmectomy; (2) Without airway compromise: medical treatment with steroids
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Thyroid Mass Workup
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(1) 15% of solitary nodules are malignant; (2) If multinodular thyroid gland, risk of malignancy is ONLY 5%; (3) 90-95% present as well-differentaited cancer; (4) Lateral aberrant thyroid: usually well-differentiated papillary cancer metastatic to cervical lymph nodes
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Risk Factors for thyroid mass
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(1) History of radiation; (2) Family history of thyroid cancer; (3) age, gender
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S&S of Thyroid Mass
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(1) Voice/airway symptoms, sudden enlargement of nodule; (2) Hx of head/neck radiation therapy leads to 40% risk of developing thyroid cancer, so if patient presents with this history, proceed directly to surgery; (3) EXAM: check size, mobility, quality, adherence of mass, presence of LAD; Concerning findings include hard, fixed gland or palpable cervical lymph nodes
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Diagnosis of Thyroid Mass
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FNA is the standard of care for thyroid nodule workup; results will either be benign (65%)/suspicious or non-diagnostic (15%)/malignant (15%)
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Suspicious or nondiagnositic thyroid FNA
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Usually will be follicular thyroid carcinoma (20% will be malignant). Obligated to get a 123-Iodide scan --> 85% are "cold" nodules with a 10-25% chance of malignancy. 5% are "hot nodules" with only 1% chance of malignancy; Surgery indicated if serial T4 levels fail to refress or future biopsies are worrisome
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Benign thyroid FNA
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Obtain Ultrasound to size/differentiate nodules and cysts; obtain thyroglobulin level and follow over time. No need for surgery. 65% of nodules fit this category
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Treatment of thyroid cyst
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Drain completely (curative in 75% of cases). If cyst is >4cm, complex, or recurring even after three aspirations, send to OR for removal
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Papillary Thyroid cancer
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(1) MC type of thyroid cancer -80-85% of thyroid cancers; (2) Biggest risk factor: radiation; (3) Age group = 30-40; (4) S&S: painless mass, dysphagia, dyspnea, hoarseness, euthyroid; (5) Dx: FNA, CT or MRI to assess local invasion; (6) Mets are lymphatic; (7) Tx: lobectomy if limited, thyroidectomy if >1.5cm, +LN gets dissection, iodide-131 ablation; (8) Prognosis: worse for older patients or those with mets, 10-yr survival: 74-93%
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Follicular Thyroid cancer
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(1) Not common in pops that do not have iodine deficiency - 5-20% of all thyroid cancers; (2) Risk Factors: dyshormonogenesis; (3) Age group = 40-50; (4) S&S: painless mass, rarely hyperfunctional; (5) Dx: FNA, CT or MRI to asess local invasion; (6) Hematogenous spread; (7) Treatment: <4cm lobectomy, if large then thyroidectomy; +LN gets radical neck dissection, and 131-iodide ablation with mets; (8) Prognosis: worse for older patients or those with mets, >4cm size. 10-yr survival is 60-80%
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Medullary Thyroid cancer
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(1) Not common, but associated with MEN IIA, IIB - 5-10% of all thyroid cancers; (2) Risk Factors: MEN II in 30-40%; (3) Age group = 50-60; (4) S&S: painful mass, palpable nodes, dysphonia, dyspnea, hoarseness; (5) Dx: FNA, presence of amyloid is diagnostic (check for calcitonin!); (6) Lymphatic (local neck and mediastinal nodes) and local (into trachea and esophagus) spread; (7) Tx: Total thyroidectomy if sporadic; if familial, add central neck node dissection. No value for 131-iodide ablation; follow patients with calcitonin levels; (8) Prognosis: 10-yr survival is 70-80%
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Anaplastic Thyroid cancer
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(1) Rarest, but worst prognosis - William Rehnquist had this; accounts for 1-5% of thyroid cancers; (2) Risk Factors: prior diagnosis of well-differentiated thyroid cancer, iodine deficiency; (3) Age: 60-70; (4) S&S: rapidly enlarging neck mass (large mass at presentation), neck pain, dysphagia, hard fixed LN [50%]; (5) Dx: FNA; (6) Mets: aggressive local disease, 30-50% have synchronus pulmonary mets at time of diagnosis; (7) Tx: debulking resection of thyroid and adjacent structures, XRT, Doxorubicin-based chemo; (8) Prognosis: POOR - median survival 4-5 months
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Development of parathyroid glands
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(1) Superior parathyroid glands (2) develop from 4th pharyngeal pouch; (2) Inferior parathyroid glands (2) develop from 3rd pharyngeal pouch
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Parathyroid Hormone
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(1) Synthesized by parathyroid glands; (2) Serum calcium levels regulate secretion of cleaved PTH by negative feedback mechanism; (3) Bone: stimulates osteoclasts, inhibits osteoblasts --> results in release of calcium and phosphate; (4) Kidney: increases reabsorption of calcium, excretion of phosphate; (5) GI tract: stimulates 1-alpha-hydroxlation of 25-OH-vitD, which increases intestinal absorption of dietary calcium and phosphate, promotes mineralization, enhances PTHs effect on bone
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Hypercalcemic crisis (calcium > 13 mg/dL and symptomatic)
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Treat with saline, lasix, bisphosphonates, and if needed antiarrhythmic
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Increased PTH
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Increased Ca2+ - think STONES, BONES, GROANS, and MOANS
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Calcitonin
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Secreted by thyroid C cells - inhibits bone resorption by blocking calcium release; Increases urinary excretion of calcium and phosphate and works as a counterregulatory hormone to PTH; NOTE: can form amyloid - reason why medullary thyroid cancer may result in amyloidosis!
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Primary Hyperparathyroidism
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Due to overproduction of PTH causing increased absorption of calcium from intestines, increased vitamin D3 production, and decreased renal calcium excretion, thereby raising the overall serum calcium and lowering the amount of Phosphorus
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S&S of Primary Hyperparathyroidism
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(1) STONES: kidney stones; (2) BONES: bone pain, pathologic fractures, subperiosteal resorption; (3) GROANS: nausea, vomiting, muscle pain, constipation, pancreatitis, peptic ulcer disease; (4) MOANS: lethargy, confusion, depression, paranoia
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Etiology of primary hyperparathyroidism
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(1) Solitary adenoma (90%); (2) Four-gland hyperplasia (10%); (3) Cancer: <1%
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Diagnosis of primary hyperparathyroidism
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(1) Elevation of plasma PTH, with inappropriately high serum calcium. Check urine for calcium to r/o familial hypocalciuric hypercalcemia (will be low if familial disease, and high if primary hyperparathyroidism)
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Treatment for primary hyperparathyroidism
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(1) Solitary adenoma: solitary parathyroidectomy with neck exploration +/- biopsy 3 remaining glands; if preop Sestamibi scan done, no need for neck exploration; (2) Multiple gland hyperplasia: remove 3 glands, or all four with reimplantation of at least 30g parathyroid tissue in forearm or other accessible site to retain function
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Do all patients with hypercalcemia have hyperparathyroidism?
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Of course NOT! Not all patients with hypercalcemia have hyperparathyroidism. Hypercalcemia of malignancy (due to tumorsecreted PTH-related protein) must be ruled out. Malignancies commonly implicated include colon, lung, breast, prostate, head, neck, and multiple myeloma.
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Secondary hyperparathyroidism
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Increased PTH due to hypocalcemia that is a result of chronic renal failure (phosphate retention --> binds calcium), GI malabsorption, osteomalacia, or rickets. Diagnosis is usually made by labs in asymptomatic patients; usually due to four-gland hyperplasia
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Treatment of secondary hyperparathyroidism
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(1) NONSURGICAL: in renal failure patients, correct calcium and phosphate; restrict phosphate intake, treat with phosphorous-binding agents and calcium/vitamin D supplementation. Adjust dialysate to maximize calcium and minimize aluminum; (2) SURGICAL: indicated for intractable bone pain or pruritus, or pathologic fractures with failure of medical therapy. No role for parathyroid surgery in secondary hyperPTH; renal tx if necessary
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Tertiary hyperparathyroidism
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(1) Due to persistent hyperparathyroidism after treatment for secondary hyperparathyroidism. Due to autonomously functioning parathyroid glands that are resistant to negative feedback from high calcium levels. Usually s/p renal transplant; (2) Usually short-lived phenomenon; if persistent, surgery is indicated by doing 3.5-gland parathyroidectomy
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Hypoparathyroidism
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Uncommon; usually surgically induced following total thyroidectomy and often transient; may also have congenital absence of all four glands. DiGeorge syndrome: absence of parathyroid and thymus. Functional: Chronic hypoMAGNESEMIA can cause hypoPTH
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S&S of Hypoparathyroidism
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(1) Numbness and tingling of circumoral area, fingers, toes; (2) Anxiety, confusion; (3) May progress to tetany, hyperventilation, seizures, heart block
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Treatment of hypoparathyroidism
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(1) Supplementation with PO calcium and vitamin D (to help GI absorption); (2) Pseudohypoparathyroidism: familial disease causing resistance of PTH at target tissue. Patients remain hypocalcemic and hyperphosphatemic despite bone resorption from elevated PTH. Treatment consists of calcium and vitamin D supplementation
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Signs of Hypocalcemia
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Chvostek: Contraction of facial muscles when tapping on facial nerve. Trousseau: Development of carpal spasm by occluding blood flow to forearm.
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Parathyroid cancer
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(1) 40-50% present with firm, fixed palpable mass. (2) Extremely high calcium and PTH levels, usually with high levels of hCG - tumor marker; (3) Neck pain, voice change
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Treatment of parathyroid cancer
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(1) En bloc surgical resection of mass and surrounding structures, along with ipsilateral thyroid lobectomy, ipsilateral lymph node dissection; (2) Postop XRT and chemo NOT beneficial; (3) Post-op complications include damage to recurrent laryngeal nerve, severe hypocalcemia; (4) 5-yr survival is 70%
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Adrenal adenoma
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(1) Most unilateral; (2) If adrenal gland < 6cm, observe unless hormonally active (increased cortisol, ACTH) or increasing in size; (3) If adrenal gland is >6cm, surgically resect due to increased risk of adrenocortical carcinoma
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Adrenal cortical carcinoma
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Very RARE adrenal tumor; women > men, peak < 5yo or 30-40yo; S&S: vague abdominal complaints 2/2 enlarging retroperitoneal mass with symptoms related to overproduction of steroid hormone; 50% secrete cortisol, resulting in Cushing's Syndrome
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Diagnosis of adrenal cortical carcinoma
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(1) 24-hr urine collection for cortisol, aldosterone, catecholamines, metanephrines, vanillylmandelic acid, 17-OH corticosteroids, 17-ketosteroids; (2) CT (lesions >7mm) or MRI (esp for assessing IVC invasion); (3) CXR to rule out pulmonary mets
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Treatment of adrenal cortical carcinoma
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(1) Radical en bloc resection, but only 1/3 of adrenal carcinomas are operable; (2) If resection cannot be completed, debulk to reduce amount of cortisol-secreting tissue; (3) No role for chemothreapy
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What is Nelson's Syndrome?
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(1) Occurs after 10% of bilateral adrenalectomies, where rapid enlargement of a pituitary adenoma occurs after the removal of both adrenal glands 2/2 excess production of ACTH, resulting in visual disturbances, hyperpigmentation, amenorrhea
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Cushing Syndrome
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Excessive cortisol production caused by either: (1) iatrogenic administration of corticosteroids; (2) pituitary tumor that secretes ACTH [technically Cushing's Dz]; (3) Extopic ACTH by tumor elsewhere stimlating adrenal cortisol production; (4) Adrenal tumor that secretes cortisol
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S&S of Cushing Syndrome
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(1) Appearance: weight gain, truncal obesity, extremity wasting, buffalo hump, moon facies, acne, purple striae, hirsutism; (2) Physiologyic: glucose intolerance, amenorrhea, decreased libido, depression, impaired memory, muscle weakness
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Diagnosis of Cushing Syndrome
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(1) CONFIRM HYPERCORTISOLISM: low dose dexamethasone test; 24-hr urine cortisol; direct measurement of serum cortisol; (2) DETERMINE IF PITUITARY INDEPENDENT OR DEPENDENT: high-dose dexamethasone test; (3) CT (adrenals) can help distinguish cortical hyperplasia from tumor; (4) Petrosal sinus sampling (elevated ACTH if pituitary tumor); (5) Adrenal cortisol production indacted when high cortisol, low ACTH and no suppression of cortisol with high-dose dexamethasone suppression test
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Low Dose vs. High Dose dexamethasone suppression test
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(1) Low-dose dexamethasone (2 mg) normally decreases urinary cortisol levels in normal patients. Lack of suppression confirms hypercortisolism; (2) High-dose dexamethasone (8 mg) will only decrease urinary cortisol if pituitary-dependent cause of ↑ ACTH (Cushing’s disease), but will not suppress cortisol at all if cause is either ectopic ACTH production or a primary adrenal tumor
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Most common cause of ectopic ACTH production
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Small cell lung cancer (a.k.a. oat cell carcinoma), followed by carinoid tumors.
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Most common cause of secondary adrenal insufficiency
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Iatrogenic due to long-term glucocorticoid therapy; The sudden cessation of long-term glucocorticoid therapy can precipitate adrenal insuffi ciency because it suppresses the intrinsic control by the hypothalamus and pituitary. Six months may be required for the intrinsic controls to return to normal.
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Addisonian crisis: classic scenario
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A patient with known Addison’s disease presents with acute upper abdominal pain, with peritoneal signs and confusion.
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Stress-dose steroids
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Patients with Addison’s disease or who have been taking exogenous steroids for 6 months or longer are likely to require stress-dose steroids perioperatively. The timing and dose may vary depending on the planned procedure and baseline doses of the patient
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Diagnosis of adrenal insufficiency
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(1) Hyponatremia, hyperkalemia due to decreased aldosterone; (2) ACTH stim test: give ACTH, measure cortisol level after 30 mins; if adrenal failure is present, there will be no increase in cortisol; (3) Baseline ACTH level elevated in patients with primary failure 2/2 absence of negative feedback
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Hyperaldosteronism
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(1) Primary = Conn's Syndrome; 2/2 aldosterone-secreting tumor or idiopathic adrenocortical hyperplasia; (2) Secondary due to elevated renin --> leading to elevated aldosterone
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Describe RAAS pathway
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Renin is produced in the juxtaglomerular (JG) cells of the kidney when blood pressure is low, and stimulates conversion of angiotensinogen to angiotensin I in the kidney. Angiotensin I is converted to angiotensin II in the lung. Angiotensin II causes adrenals to produce aldosterone.
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S&S of hyperaldosteronism
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(1) HYPERTENSION; (2) muscle weakness and cramping; (3) Hypokalemia; (4) Polyuria, polydipsia
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Treatment of primary hyperaldosteronism
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(1) Hyperplasia: medical rx with spironolactone, nifedipine, amiloride and/or other antihypertensive. NO SURGERY! (2) Adenoma: lap adrenalectomy
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Neuroblastoma
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Embryonal neural crest tumor occurring primarily in children (small round blue cell tumor); 4th most common pediatric malignancy and can occur anywhere along sympathetic chain - 50% in adrenal, 25% in paraspinal ganglia, 20% in thorax, 5% in pelvis. Is an aggressive tumor that commonly presents with distants mets
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Associated diseaes with neuroblastoma
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(1) Neurofibromatosis; (2) Beckwith-Wiedemann syndrome; (3) Trisomy 18
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S&S of neuroblastoma
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(1) Abdominal or flank mass; (2) Respiratory distress; (3) Subcutaneous blue tumor nodules [blueberry muffin sign]
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Diagnosis of neuroblastoma
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(1) CT for staging, MRI; (2) Urinary tumor markers: elevated 24hr homovanillic acid (HVA), vanillylmandelic acid (VMA), and metanephrines
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Most common extraadrenal location of pheochromacytoma
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The organ of Zuckerkandl (to left of aortic bifurcation at inferior mesenteric artery)
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Pheochromocytoma
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Chromaffin cell tumor that is most commonly in adrenal medulla (<90%) but may be anywhere along sympathetic chain; MC site of extra-adrenal pheo is organ of Zuckerkandl; If bilateral, more likely to be familial. If extra-adrenal, more likely malignant
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Associated risk factors for pheochromocytoma
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(1) MEN IIA, MEN IIB (usually result in bilateral adrenal tumors); (2) Von Hippel-Lindau disease; (3) Neurofibromatosis
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10% rule for pheochromocytomas
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10% are malignant; 10% familial; 10% extra-adrenal; 10% bilateral; 10% in children
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S&S of pheochromocytoma
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(1) HTN: may be sustained elevated, normal with paroxysmal HTN, or sustained HTN with acute elevations; MC presenting symptom! (2) Headaches; (3) Anxiety, palpitations, pallow, diaphoresis
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Diagnosis of pheochromocytoma
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(1) 24hr urine for catecholamine by-products, VMA, metanephrine, normetanephrine; (2) Serum epinephrine and norepinephrine [note: if elevated epinephrine, must be adrenal tumor!]; (3) Clonidine test: will suppress plasma catecholamine concentrations in normal patients, but not in patients with pheochromocytoma
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Treatment for pheochromocytoma
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(1) Pre-op alpha-adrenergic blockade with phenoxybenzamine, followed by beta-blockers for persistent tachycardia; (2) Intraop BP monitoring CRUCIAL; (3) Important to ligate veins first to prevent unintentional release of catecholamines that may result from manipulation of adrenal gland
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Order of blockade for pheochomocytoma
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Alpha blockade must precede beta blockade. The use of β-blockers will cause negative inotropic effects and result in unopposed α-induced vasoconstriction, which may precipitate malignant hypertension and cardiac failure.
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Blood supply of pituitary
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(1) Anterior lobe lacks a direct supply. Portal channels from the hypothalamus and posterior pituitary supply it; (2) Posterior pituitary is supplied by middle and inferior hypophyseal arteries, branches of the internal carotid artery; (3) Drains via cavernous sinuses to petrosal sinuses to jugular veins.
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Pituitary adenoma
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Benign tumors arising from anterior lobe - divided into two types depending on size: (1) macroadenoma: >1cm diamter; (2) microadenoma <1cm diameter
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Stalk effect and hyperprolactinemia
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Macroadenomas compress the pituitary stalk, preventing dopamine from traveling from hypothalamus to posterior pituitary gland where it normally inhibits prolactin production. Thus, compression results in hyperprolactinemia (i.e., nipple discharge).
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Prolactinoma
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MC type of pituitary adenoma; causes secondary amenorrhea, galactorrhea
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Medical therapy for pituitary adenoma
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(1) For prolactinomas: bromocriptine; (2) For GH-secreting adenomas: somatostatin, which decreases tumor size in 20-50%, normalizes GH in 50%, and normalizes IGF-1 in 40-80%
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Sheehan's Syndrome
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Postpartum infarction and necrosis of pituitary leading to hormonal failure; caused by Pituitary ischemia due to hemorrhage, hypovolemic shock, pituitary portal venous thrombosis.
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SIADH
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Impaired water secretion with hypersecretion of ADH resulting in increased urinary sodium with elevation of urine osmolality. May be caused by CNS injury, cancer, trauma, or drugs
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Diabetes Insipidus
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Decreased ADH secretion; impaired water consevation with large volumes of urine leading to increased plasma osmolality and thirst. About 1/3 are idiopathic, 2/3 due to tumor or trauma
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