Term
|
Definition
Zona glomerulosa
Mineralocorticoid production
Aldosterone 95% of min. activity
Zona fasciculata microvacuolated glucocorticoids
Zona reticularis nonvacuolated
Glucocorticoids, mostly from zona fasciculata
Sex hormones, mostly from zona reticularis |
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Term
|
Definition
Inhibits glucose uptake
Predisposes to
Glucose intolerance
Hyperglycemia
Diabetes mellitus
Osteoporosis due to renal calcium and phosphorus wastage
Impairs cellular and humoral immunity
Long-term cortisol therapy is associated with
Infections (such as Tuberculosis)
Poor wound healing |
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Term
|
Definition
Sodium absorption
Potassium excretion
hypokalemia
hypertension
HYPERALDOSTERONISM SHOULD BE THOUGHT OF IN HYPERTENSIVE, HYPOKALEMIC PATIENTS |
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Term
| Adrenal Cortex Hyperfunction |
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Definition
| There are three clinical hyperadrenal syndromes related to the three types of corticosteroids Cushing’s syndrome Hyperaldosteronism Adrenogenital syndromes |
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Term
| Cushing's Clinical Course |
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Definition
Classic features are usually easily recognized
Prognosis is excellent when the cause can be corrected
Diagnosis is confirmed by
Increased serum cortisol
Elevated urinary cortisol metabolites such as 17-hydroxycorticoid
Dexamethasone Suppression Test may assist
Low dose: low cortisol subsequently in normals, not Cushing’s
High dose: suppression with hyperplasia, not functioning tumor |
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Term
| Pituitary Hypersecretion of ACTH |
|
Definition
65 to 70% of endogenous hypercortisolism
Cushing’s Disease
Basophilic microadenoma, classically
Corticotroph hyperplasia only, 15%
Bilateral adrenal hyperplasia
Elevated serum ACTH
F:M = 5:1
Mostly young adults (3rd & 4th decades) |
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Term
|
Definition
10 to 15% of endogenous Cushing’s syndrome
Caused by non-pituitary tumors
Small cell carcinoma of the lung
Carcinoids of bronchus, pancreas
Malignant thymoma
Medullary thyroid carcinoma
Gastrinoma |
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Term
|
Definition
| Nelson’s Syndrome is enlargement of a pituitary adenoma in a patient with Cushing’s disease whose adrenals have been removed. Following bilateral adrenalectomy and normalization of cortisol levels that had suppressed hypothalamic CRH production, an increase in CRH occurs, which then has a trophic effect on the tumor, stimulating its growth. Regulatory gene mutations and mutations in the glucocorticoid receptor may also be important in determining tumor behavior. |
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Term
| Primary Hyperaldosteronism |
|
Definition
is chronic excess aldosterone secretion independent, or virtually so, of the renin-angiotensin system
Plasma renin is decreased
Sodium retention
Chvostek’s sign
Tapping facial nerve near
parotid elicits muscle spasm
Hypokalemia
hypertension
Trousseau’s sign
Compressing forearm elicits
spasm of wrist and hand.
Diagnosis – clinical suspicion, laboratory
Increased aldosterone
Decreased renin
Treatment
Adenoma - surgical removal
hyperplasia - medical |
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Term
| Secondary Hyperaldosteronism |
|
Definition
Secondary hyperaldosteronism occurs in response to activation of the renin-angiotensin system. Plasma renin is increased.
Associated conditions include
Congestive heart failure
Decreased renal perfusion
Hypoalbuminemia
Pregnancy |
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|
Term
| 21 Hydroxylase Insufficiency |
|
Definition
90% of cases of adrenal virilism
Three distinctive syndromes reflect total lack to mild deficiency.
Salt-wasting syndrome
Simple Virilizing Adrenogenital Syndrome without Salt-wasting
Non-classic Adrenal Virilism |
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Term
|
Definition
Total lack of 21-hydroxylase
Virtually no mineralocorticoid synthesis
Deficient cortisol synthesis
Virilization
Females: easily recognized at birth
Males: generally unrecognized at birth |
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Term
| Simple Virilizing Adrenogenital Syndrome without Salt-wasting |
|
Definition
Less than total lack of 21-hydroxylase
Aldosterone level is
Reduced
Sufficient for salt re-absorption
Glucocorticoid level
Reduced
No feedback inhibition of ACTH
Testosterone is increased
Adrenal cortical hyperplasia |
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|
Term
| Non-classic Adrenal Virilism |
|
Definition
More common than the others
Asymptomatic, or
Mild manifestations such as hirsutism |
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Term
| Hypoadrenalism--Three Types |
|
Definition
Primary Acute Adrenocortical Insufficiency
Waterhouse-Friderichsen Syndrome
Addison’s Disease |
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|
Term
| Primary Acute Adrenocortical Insufficiency |
|
Definition
Crisis; stress, chronic insufficiency
Too rapid withdrawal of steroids
Failure to increase dose of steroids during acute stress in
adrenal atrophy
adrenalectomized patient
Massive destruction of adrenals
Neonates; difficult delivery; hypoxia, hemorrhage
Post-surgical DIC; hemorrhagic infarction; anticoagulants
Massive hemorrhage in bacterial infection (Waterhouse-Friderichsen Syndrome) |
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Term
|
Definition
Primary Chronic Adrenocortical Insufficiency
Affects adults mostly
Any age
Insidious onset
>90% of cortical cells destroyed
60 to 70% due to Autoimmune adrenalitis
Adrenal involvement only or
Other endocrine glands may be affected
Circulating anti-adrenal antibodies, about 50%
Increased incidence HLA-B8, DR3
Morphology
Many lymphocytes, plasma cells
Diffuse atrophy of all zones
Corticoids and Catecholamines are lost
SYMPTOMS: Hyperpigmentation
skin
mucous membranes
hair
Vitiligo
GI symptoms
anorexia
nausea
vomiting
diarrhea
weight loss
Weakness, fatigability
Hypotension
Lack of aldosterone
increased potassium
decreased sodium
Lack of cortisol
increased ACTH
decreased glucose |
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Term
| Addison's Disease Clinical Features |
|
Definition
Decreased glucose
Increased ACTH
To confirm the diagnosis
Administer ACTH
No cortical (cortisone production) response
Complications may be induced by stress
Vomiting and abdominal pain
Hyperkalemic cardiac arrhythmias
Hypotension and vascular collapse
Addisonian crisis (hypoglycemic cerebral)
Death in untreated patient |
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Term
|
Definition
Hypertension is the dominant feature
May be intermittent
2/3 sustained
Paroxysmal in less than half
Stress
Exercise
postural changes
palpation
But………
Sudden catecholamine release may cause
Congestive heart failure
Myocardial infarction
Ventricular fibrillation
Pulmonary edema
Cerebral hemorrhage
Death |
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