Addison`s disease or adrenocortical insufficiency means inadequate secretion of corticosteroid hormones from the zona fasciculata of the adrenal cortex of the adrenal gland which may be primary resulting from adrenal disease or secondary as a result of a deficiency of adrenocorticotrophic hormone ACTH
  • Drugs such as ketoconazole rifampicin phenytoin aminoglutethemide metyrapone and mitotane
  • Infection eg tuberculosis TB and HIV
  • Spontaneous adrenal hemorrhage can occurs in patient with fulminate or acute meningococcal septicemia called Weterhouse-Friderichsen syndrome which associated with bilateral adrenal hemorrhage and infarction associated with disseminated intravascular coagulopathay (DIC) and may also occurs secondary to trauma severe stress infection and coagulopathies
  • Inflitrative disorders such as sarcoidosis and amyloidosis and hemochromatosis
  • Congenital adrenal hyperplasia
  • Metatatic deposits from other cancer
  • Pan hypopituitarism
  • ACTH deficiency
  •  Exogenous glucocorticoid therapy with suppression of the adrenal glands is the most common cause of secondary adrenal insufficiency when the steroids are discontinued which the steroid therapy inhibits the production of ACTH  and leads to adrenal cortical atrophy 
  • After removal of the adrenal gland post adrenalectomy
  •  Pituiatery or hypothalamic tumors
  • Pituitary hemorrhage such as postpartum Sheehan`s syndrome
  • Trans-sphenoidal resection of pituitary gland
Symptoms and signs
  • Acute adrenal insufficiency should be suspected in stressed patients with any risk factors
  • Symptoms and signs may similar to sepsis or infection and present with fever nausea lethargy abdominal pain and severe hypotension hypoglcaemia dehydration and shock
  • Chronic adrenal insufficiency such as occurring in patients with metastatic tumors may give symptoms such as fatigue salt craving weight loss nausea vomiting abdominal pain and diarrhea
  • Hyper pigmentation of the skin and cirumoral pigmentation due to secretion of large amount of ACTH and  CRH with an increase in melanocyte stimulating hormones MSH
  • Muscle wasting
  • Postural decreased blood pressure( hyoptension )due to sodium and water loss
  Investigations and diagnosis
Hyponatremia decreased serum sodium NA+ and
Hyperkalemia increased serum potassium K+ and
Fasting or reactive hypoglycemia
Increased ACTH in primary causes and decreased in secondary causes
Decreased cortisol
ACTH stimulation test
ACTH 250 ug is infused intravenously and cortisol levels are measured at 0 , 30 , 60 minutes
Peak cortisol levels less than 20 ug|dl suggest adrenal insufficiency
ACTH  levels also enable one to distinguish primary from secondary causes
High ACTH levels with low plasma cortisol levels are diagnostic of primary adrenal insufficiency
In patients with acute attack are treated by
Volume resuscitation with at least 2-3 litre of .9 saline solution or 5 % dextrose in saline solution
Blood should be obtained for electrolytes showing decreased NA+ and increased K+  blood glucose decreased and cortisol level decreased
ACTH increased in primary and decreased in secondary and eosinophilea
Drugs treatment give dexamethasone 4 mg intravenous
Hydrocortisone 100 mg intravenous every 6 hours after measure level of cortisol in the blood to avoid it is interference with it
After patient become stabilized the underlying causes should be known and treated
Maintenance doses of oral hydrocortisone 15-20 mg in the morning and 10 mg in the evening
Mineralocorticoids such as fludrocortisone .05-.1 mg daily may be required once the saline infusions are discontinued

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