Pediatric emergency medicine trisk 1881 1881
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Current Evidence
Acute adrenal insufficiency occurs when the adrenal cortex fails to produce enough
glucocorticoid and mineralocorticoid in response to stress. Because the production of
corticosteroids by the adrenal cortex is under pituitary and hypothalamic control, adrenal
insufficiency can result from either an adrenal (primary) or hypothalamic–pituitary
(secondary) disorder. Specific adrenal problems resulting in adrenal insufficiency include
inborn errors of hormonal biosynthesis (discussed in the Congenital Adrenal Hyperplasia
section), autoimmune destructive processes, X-linked adrenoleukodystrophy, and adrenal
hemorrhage. Hypothalamic–pituitary causes include CNS tumors, trauma, and radiation
therapy for a variety of neoplastic disorders. Exogenous administration of glucocorticoids also
suppresses the adrenal–pituitary axis, an effect that often lasts well beyond the cessation of
corticosteroid therapy.
TABLE 89.5
COMMON CAUSES OF ACUTE ADRENAL INSUFFICIENCY IN CHILDREN
Primary adrenal insufficiency
Adrenoleukodystrophy (X-linked)
Congenital adrenal hyperplasia
Autoimmunity
Tuberculosis
Meningococcal septicemia
Adrenal hemorrhage
Secondary adrenal insufficiency
Suppression of adrenocorticotropic hormone by pharmacologic doses of glucocorticoid
administration
Pituitary or hypothalamic tumors
Central nervous system surgery or irradiation
Structural abnormalities (septo-optic dysplasia)
Congenital hypopituitarism
Glucocorticoids are essential for withstanding stress; therefore, adrenal insufficiency is most
likely to be manifested during an intercurrent infection or after trauma. Mineralocorticoids,
especially aldosterone, play an important role in salt and water homeostasis by promoting salt
reabsorption in the distal renal tubules and collecting ducts. Mineralocorticoid production is
primarily regulated by the renin–angiotensin system; thus, adrenal insufficiency resulting from
hypothalamic–pituitary causes is rarely associated with a lack of aldosterone. However,
aldosterone deficiency is a common feature in primary adrenal insufficiency. Because of the
nature of the pituitary–adrenal axis, primary adrenal insufficiency is accompanied by
significantly elevated ACTH levels.
