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Flashcards in Adrenals Deck (24):
1

3 cortical zones of the adrenal cortex

Zona Glomerulosa -- 5-10% of the cortex (outer) and responsible for MINERALOCORTICOID PRODUCTION (Aldosterone)

Zona Fasciulata -- 80% of the cortex (middle) and responsible for GLUCOCORTICOID PRODUCTION (cortisol)

Zona Reticularis -- 5-10% of the cortex (innermost), responsible for SEX STEROID PRODUCTION (Testosterone)

Salt, Sugar, Sex

2

Medulla of Adrenals

CHROMAFFIN CELLS, responsible for secreting EPINEPHRINE (80%) and NOREPINEPHRINE (20%)

3

Organs of Zuckerkandl

Separate, extra-adrenal collections of chromaffin cells that are part of the sympathetic ganglia

Similar to the medulla of the adrenals (catecholamines)

Located adjacent to the aorta at the bifurcation of the iliacs

Important because they can give rise to CATECHOLAMINE SECRETING TUMORS (paragangliomas)

4

Congenital Adrenal Hyperplasia

Causes enzyme defects in steroid synthesis -- major ones affected are 21 HYDROXYLASE (95%) and 11 BETA HYDROXYLASE (5%)

Causes adrenal VIRILISM --> enzymes to make cortisol and aldosterone are STOPPED --> EVERYTHING shunted towards TESTOSTERONE production --> leads to ambiguous genitalia at birth

Males appear normal at birth, but present 10-15 days later due to SALT WASTING

Females present immediately with ambiguous genitalia (normal internal reproductive tract)

HYPERSECRETION OF ACTH due to a reduction of cortisol inhibition

This leads to ADRENAL HYPERPLASIA as the adrenals try to make more cortisol

Treat via steroid replacement to turn off the excess ACTH production!

5

SALT WASTING

Leads to fatal hyponatremia, dehydration, electrolyte disturbances (hyperkalemia) due to the decrease of aldosterone production

6

Chronic adrenal cortical insufficiency is referred to as...

ADDISON'S DISEASE

7

Addison's Disease

Chronic deficiency of glucocorticoids and mineralocorticoids

Primary cause is by autoimmune adrenalitis --> body produces anti-adrenal antibodies that SHUT OFF ACTH RECEPTORS, preventing adrenals from making any cortisol

Small glands, diffuse atrophy of the cortex, intact medulla

Can be part of Adrenal Polyglandular Syndrome (type 1 = 60% have it, type 2 = 100% have Addison's)

Other causes -- infections (TB), amyloidosis, metastatic tumors, malignant lymphoma, AIDS with dissemintated CMV --> all of these take over the adrenal gland so that there is NOT ENOUGH TISSUE left to produce the cortisol and mineralocorticoids the body needs!

**More than 90% of the adrenal cortex is destroyed before the symptoms of Addison's are even noticeable!**

8

Adrenal Polyglandular Syndrome

APS Type 1 --> autosomal recessive, 60% have AD, most have hypoparathyroidism and chronic mucocutaneous candidiasis as well

APS Type 2 -- Schmidt syndrome, more common than type 1, ALL HAVE AD, and may be associated with Hashimoto's and/or Diabetes

Various endocrine abnormalities may present together as a group, but may not present SYNCHRONOUSLY (i.e. get classic adrenal insufficiency one time but just hypothyroidism at next visit)

9

SYMPTOMS of Addison's

Weakness
Weight loss
Hypotension
Diarrhea
Vomiting
Abdominal Pain
Electrolyte Imbalances

Hyperpigmentation --> excessive ACTH precursor hormone (POMC) -- leads to excess stimulation of melaoncytes to produce melanin

10

ACUTE Adrenal Cortical Insufficiency

Occurs with the use of chronic exogenous steroids

Doses suppress endogenous adrenal production of steroids

ABRUPT withdrawal will produce an ADRENAL CRISIS and a patient will be unable to compensate to stress (steroids suppress HPA, duh, so when you take them off ABRUPTLY, then we still have no ACTH, cortisol, aldosterone, etc) --> emergency! Taper dose of steroids!

11

Waterhouse-Friedrichsen Syndrome

Defined as an acute, bilateral adrenal hemorrhagic infarction

May be due to SEPTICEMIC SHOCK with sudden vascular collapse, DIC, and adrenal hemorrhage

Most common cause is NEISSERIA MENINGIDITIS!!!!!!! Less so pneumococcus, pseudomonas, staph, H. flu

Present with PETECHIAL RASH

RAPID ONSET, VERY FATAL

Massively hemorrhagic gland with NECROSIS secondary to HYPOXEMIA

Rare, but important cause of acute adrenal cortical insufficiency

12

Cushing Syndrome

Bilateral, pituitary based excess production of ACTH; adrenal cortical enlargement

Cushing's DISEASE = tumor secreting ACTH; SYNDROME = symptoms due to other things (not a tumor)

13

Symptoms of Cushing's

Truncal obesity
Obesity of the face and neck (moon face, buffalo hump)
Hirsutism
Purple striae
Osteoporosis
Weakness
Emotional disturbances
Fatigue
Amenorrhea
Cardiac Hypertrophy
Hypertension

14

Causes of Cushings

Cushings DISEASE 60-70% (ACTH tumor) - LABS = ELEVATED ACTH and ELEVATED CORTISOL

ADRENAL CORTICAL ADENOMA/CARCINOMA (25%) -- ACTH independent, a tumor that has autonomous hypersecretion of cortisol with suppression of ACTH; adrenal cortex and other glands atrophic! Labs = ELEVATED CORTISOL, LOW ACTH

Paraneoplastic ACTH syndrome -- 10-15% -- most commonly associated with SMALL CELL CARCINOMA OF THE LUNG, carcinoid tumors of the bronchus or pancreas, malignant thymoma, pheochromocytoma, medullary carcinoma of the thyroid or gastrinomas (these cancers all produce ECTOPIC ACTH)

BILATERAL ADRENAL GLAND HYPERPLASIA

Labs = ECTOPIC elevated ACTH production, ELEVATED cortisol

15

Primary HYPERALDOSTERONISM

Two main causes, characterized by a suppression of plasma renin activity, hypokalemia, sodium RETENTION and HTN

Too much aldosterone = increased serum sodium, decreased serum K; increase in aldosterone = decrease in plasma renin activity!

CONN'S SYNDROME --> aldosterone producing adrenal cortical adenoma (65%); adrenal cortical carcinomas are RARE causes; typically a small, solitary, encapsulated lesion less than 2 cm

BILATERAL IDIOPATHIC HYPERPLASIA OF THE ADRENALS --> 30%, unknown mechanism


HTN may be their ONLY SYMPTOM

16

Adrenal Cortical Adenoma

Benign neoplastic proliferation associated with ENDOCRINE HYPERFUNCTION

Associated with CONN'S, CUSHING, VIRILIZATION, FEMINIZATION

Accounts for 65-70% of hyperaldosteronism and 5-10% of Cushing Syndrome

UNILATERAL and SOLITARY

Less than 5 cm generally --> Virilizing type largest, Cortisol middle, Aldosterone smallest

Cell types variable, commonly mixed

17

Adrenal Cortical CARCINOMA

These are rare (0.02%)

Bimodal distribution --> 1st/2nd decade, 5th/6th decade; F > M

Palpable abdominal mass; Cushing Syndrome COMMON; virilization, hyperaldosteronism, or NO symptoms also common --> carcinomas are usually NOT HYPERFUNCTIONING

Gross -- can weigh up to 3000 grams!! Encapsulated usually, but can become infiltrative when larger

Multinodular growth, hemorrhage, necrosis

Tx -->These are AGGRESSIVE --> resection followed by chemo; tendency to invade the adrenal vein, vena cava, lymphatics!

Metastases can travel to regional lymph nodes as well as periaortic lymph nodes

Hematogenous travel allows spread to the lungs, as well as other organs

Children better prognosis

18

PHEOCHROMOCYTOMA

Neoplasm of the adrenal medulla, specifically of CHROMAFFIN CELLS (Epi, NE)

Symptoms related to excess catecholamines --> headache, palpitations, flushing, nausea, diaphoresis, constipation, HTN

90% sporadic; Genetic associations with MEN syndrome, neurofibromatosis, Von Hippel Lindau

Gross --> solitary, unilateral (multiple tumors or bilaterality may be associated with MEN syndromes); non-homogenous tumor; red with hemorrhage, necrosis, degeneration

Histo - ZELLBALLEN PATTERN (trabecular, alveolar, nested), SPINDLING with lots of vascularity, S100+ and Chromogranin++

Tx --> ALPHA BLOCKADE and THEN BETA BLOCKADE

19

GANGLIONEUROMA

Benign tumor of mature sympathetic ganglion cells with Schwann cells and collagen

Older people, F > M

Common locations --> posterior mediastinum, retroperitoneum, ADRENAL GLAND, pelvic cavity, neck

Adrenal gland types are usually small, asymptomatic

Pseudocapsule, circumscribed, light grey-tan, rubbery to gelatinous, homogenous, fasciculated, whorled

Histo - see Schwann cells and collagen, round/polygonal cells with eccentrically placed nuclei

20

MYELOLIPOMA

Benign tumor-like lesion of adipose tissue and hematopoietic elements

Looks like bone marrow

Often an INCIDENTAL finding until it hemorrhages into itself

Mixture of adipocytes and hematopoietic stem cells of different lineages

21

MEN I Syndrome

Wermer's

3 P's --> PANCREATIC ISLETS (hyperplasia or neoplasm - 70-80%), PITUITARY ADENOMA (40-60%), PARATHYROID HYPERPLASIA/ADENOMA (90-95%)

Germ line mutations in the MEN I gene at 11q13

Autosomal dominant, incomplete penetrance

Adrenal cortical nodules/adenomas (40%)

Rarely thymic carcinoid tumor

22

MEN IIA --> Sipple's Syndrome

MEDULLARY THYROID CARCINOMA (100%, bilateral, multifocal), PHEOCHROMOCYTOMA (50%, often BILATERAL), and PARATHYROID HYPERPLASIA/ADENOMA (10%)

Germ-line mutations in RET protooncogene on chromosome 10q11

23

MEN IIB or III --> Multiple mucosal neuromas

GI/mucosal neuromas (100%), Medullary thyroid Carcinoma (100%), Pheochromocytoma (35-40%, often bilateral)

Single RET AA change

Autosomal Dominant

Survival only into 3rd/4th decade vs. 6th or 7th for MEN IIa

24

Familial Medullary Thyroid Carcinoma

Variant of MEN IIA

Strong predisposition to MEDULLARY THYROID CARCINOMA

No other MEN IIA or IIB manifestations

20% of Medullary Thyroid Carcinomas are FAMILIAL

Family members need to be screen! For RET mutations; get prophylactic thyroidectomy