Lec 6 endocrine adrenal gland part 2

Lec: 6 Dr. Mohammed Alhamdany
Adrenal insufficiency
Adrenal insufficiency results from inadequate secretion of cortisol and/or aldosterone. It is potentially fatal and notoriously variable in its presentation.
Causes:
A- Secondary (?ACTH)
1- Withdrawal of suppressive glucocorticoid therapy.
2- Hypothalamic or pituitary disease.
B- Primary (?ACTH)
Addison’s disease
1- Autoimmune: either Sporadic or Polyglandular syndromes
2- Tuberculosis.
3- HIV/AIDS.
4- Metastatic carcinoma.
5- Bilateral adrenalectomy.
6- Intra-adrenal haemorrhage (Waterhouse– Friedrichsen syndrome following meningococcal septicaemia)
7- Amyloidosis.
Clinical assessment
1- Glucocorticoid insufficiency (in all patients)
a- Weight loss, anorexia, Nausea, vomiting, and Diarrhea or constipation.
b- Malaise, weakness.
c- Postural hypotension, Shock.
d- Hypoglycaemia, hyponatraemia (dilutional) and hypercalcaemia.
2- Mineralocorticoid insufficiency: (in patient with Addison disease)
a- Hypotension, Shock.
b- Hyponatraemia (depletional) and hyperkalaemia.
3- ACTH excess: (in patient with Addison disease)
Pigmentation of sun-exposed areas and pressure areas (e.g. elbows, knees), palmar creases, mucous membranes conjunctivae, and recent scars.
4- Adrenal androgen insufficiency: (in all patient):
Decreased body hair and loss of libido, especially in female.

Features of an acute adrenal crisis include circulatory shock with severe hypotension, hyponatraemia, hyperkalaemia and, in some instances, hypoglycaemia and hypercalcaemia.


Investigations
Treatment should not be delayed to wait for results in patients with suspected acute adrenal crisis. Here, a random blood sample should be stored for subsequent measurement of cortisol and, if the patient’s clinical condition permits, it may be appropriate to spend 30 minutes performing a short ACTH stimulation test before administering hydrocortisone. Investigations should be performed before treatment is given in patients who present with features suggestive of chronic adrenal insufficiency.
All patient should send for electrolyte (hyponatremia, hyperkalemia, hypercalcaemia) and glucose may be low (hypoglycemia).
Assessment of glucocorticoids
Random plasma cortisol is usually low in patients with adrenal insufficiency but it may be within the reference range, so more useful is the short ACTH stimulation test, in which cortisol levels fail to increase in response to exogenous ACTH in patients with primary or secondary adrenal insufficiency. These can be distinguished by measurement of ACTH (which is low in ACTH deficiency and high in Addison’s disease).
Assessment of mineralocorticoids
Hyperkalaemia.
Plasma renin increase.
Plasma aldosterone low.
Assessment of adrenal androgens
This is not necessary in men.
In women, dehydroepiandrosterone (DHEA) is low.
Other tests to establish the cause