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Flashcards in Adrenal Deck (22):
1

Layers of the cortex of the adrenal gland?

G:
Zona glomerulosa
-Aldosterone
F:
Zona Fasciculata
-Cortisol
R:
Zone Reticularis
-Sex Steroids

Medulla=catecholamines

2

Endogenous Hypercortisolism

1. Paraneoplastic cushing syndrome
-secretion of ectopic acth; mostly by small cell carcinoma of the lung
10% of cases of endogenous cushing syndrome
2. Primary Adrenal Neoplasms including adenoma carcinoma and rarely hyperplasia
-15-20% of cases of endogenous cushing syndrome

3

How does
Pituitary cushings
adrenal cushing
paraneoplastic cushings
iatrogenic cushings
affect the adrenal gland?

Pituitary cushings: adrenal hyperplasia
adrenal cushing: tumor (adenoma or carcinoma) or hyperplasia (diffuse or nodular)
paraneoplastic cushing: adrenal hyperplasia
iatrogenic cushing: adrenal atrophy

4

Hyperaldosteronism
Primary and secondary causes

1. Primary (independent of renin angiotensin system)
-Bilateral idiopathic hyperaldosteronism
-Adrenocortical Neoplasm
-Familial hyperaldosteronism
2. Secondary (activation of renin angiotensin system)
-Decreased renal artery profusion
-Arterial hypovolemia and edema
-Pregnancy

5

Hyperaldosteronism clinical manifestations

Hypertension with long term cardiovascular compromise (MI and stroke)
Hypokalemia cuasing neuromuscular manifestation like weakness, paresthesias, visual disturbances and occasionally tetany

6

Adrenogenital syndromes
Etiology
Primary/Secondary

conditions characterized by structural or biochemical abnormalities of the adrenal cortex which which leads to a disorder of sexual differentiation(adrenal virilism)

Etiology
Primary: adrenocortical neoplasms (usually virilizing carcinoma) or congenital adrenal hyperplasia

Secondary: Pituitary causes (excess secretion of ACTH leading to increased production of adrenal androgens, may be associated with features of cushing syndrome

7

Congenital Adrenal Hyperplasia

Autosomal recessive
-Defect in the enzyme involved in adrenal steroid biosynthesis, particularly cortisol

1. decreased cortisol--increased ATCH
2. Adrenal hyperplasia--increased precursor steroids
3. increase in synthesis of androgens
-some enzyme defects also impair aldosterone biosynthesis--salt loss
-21 hydroxylase deficiency is most common CAH defect

8

Acute adrenal insufficiency in the setting of sepsis (waterhouse-friderichsen syndrome)

1. septicemia, usually meninogocci
2. hypotension, shock, DIC
3. massive bilateral adrenal hemorrhage and destruction

9

Addison's Disease
Clinical manifestations

chronic destruction of the adrenal cortex with multiple etiologies leading to hypofunction (usually occurs when 90% of cortex destroyed)

Clinical
Initial progressive weakness and easy fatigability
Gastrointestinal disturbances like anorexia, nausea, vomiting, weight loss and diarrhea
-decreased mineralocorticoids leads to loss of sodium, hyperkalemia, volume depletion and hypotension
-hypoglycemia may occur due to glucocorticoid deficiency
-stress like infection, trauma may precipitate an acute adrenal crisis

10

Autoimmune adrenalitis
Gross and Histo

Gross: very small glands
cortices markedly thin

Micro
-diffuse atrophy of all cortical zones
-lymphoplasmacytic infiltrate
-medulla is unaffected

11

Are cushing syndrome and hyperaldosteronism most commonly caused by adenomas or carcinomas?

adenomas

12

Are virilization neoplasms most commonly caused by adenomas or carcinomas?

carcinomas

13

Adenomas of the adrenal gland
Gross
Histo

Gross
most are nonfunctional
1-2 cm diameter
yellow to yellow brown cut surface

Histo
Cytoplasm ranges from eosinophilic to vacuolated depending on lipid content
-not much mitotic activity seen
-minor degree of nuclear pleomorphism

14

Adrenal carcinoma

Rare neoplasm
any age
rare causes include Li-fraumeni sydnrome and Beckwith Wiedemann syndrome

Gross
-large poorly demarcated invasive lesions
cut surface with areas of hemorrhage and necrosis
tendency to invade the adrenal vein, vena cava and lymphatics with regional and distant metastasis
-median survival about 2 years

Histology:
-may be composed of well differentiated cells or bizarre pleomorphic cells
-invasion and metastasis are the most reliable indicators !

15

Adrenal medulla
Derivation
Cells
Secrete

neural crest derivation
chromaffin cells and their supporting sustentacular cells
-secrete catecholamines
-similar collections of cells distributed throughout the body in the extra adrenal paraganglion system

16

Pheochromocytoma

neoplasm arising from neuroendocrine cells (chromaffin cells) in the paraganglion system (adrenal medulla/etra-adrenal paraganglion system)
-give rise to surgically correctable form of hypertension

10% rule
10% extra adrenal
10% bilateral
10% malignant
25% being associated with germline mutation

1. RET gene (MEN2 and 3)
2. NF1
3. VHL
4. genes SDHB, SDHC, SDHD

17

Pheochromocytoma Gross and Histology

Gross:
small circumscribed to large hemorrhagic masses
grey tan, focally, congested cut surface
Histology:
ZELLBALLEN!!!!!
nests composed of chromaffin cells surrounded by supporting/sustentacular cells
-rich vascular network
-metastasis is required for definitive diagnosis of malignancy

18

Clinical features of pheochromocytoma

hypertension-sustained or paroxysms
-headache, sweating, anxiety, tremor
-symptoms caused by release of catecholamines which can precipitate an AMI, CHF, ventricular fibrillation, CVA
-chemical diagnosis******-urinary catecholamine metabolites
1. METANEPHRINE
2. VANILLYLMANDELIC ACID (VMA)

19

Neurobastoma

Definition: a neoplasm which arises in the adrenal medulla or extra adrenal paraganglion tissue

-one of the most common childhood neoplasms; 90% occur before age 5
-large abdominal mass in child
-younger than 2 years with fever
-older child presents with metastases

Gross
-large bulky tumors
-25% in adrenal glands
-others arise in the paravertebral regions of the posterior mediastinum and abdomen

Histo:
small, primitive appearing cells with dark nuclei, sheets or rosettes

20

MEN1

Autosomal dominant
11q13
tumor suppressor gene
3P's
1. Parathyroid
2. Pancreas
3. Pituitary

Most common: primary hyperthyroidism (hyperplasia or adenoma)

Leading cause of death: endocrine tumors of the pancreas-functional tumors metastasize

Pituitary -most commonly has prolactin secreting macroadenomas

21

MEN2A

Autosomal Dominant
Ret protooncogene (10q11.2)

1. Thyroid-medullary carcinoma -in virtually all untreated cases in first 2 decades, may b multiple (Calcitonin)

2. Adrenal medulla-Pheochromocytoma in 50% of patients though only 10% are malignant (Catecholamines)

3. Parathyroid-10-20% have hyperparthyroid (Calcium)

22

MEN 2B

Spectrum of thyroid and adrenal medullary changes similar to 2A with the following differences:

1. Mucosal ganglioneuromatosis and marfanoid habitus are characteristic
2. NO parathyroid

-RET mutation-prophylactic thyroidectomy to prevent development of medullary carcinomas