Acute Adrenal Insufficiency and Adrenal Crisis Flashcards

A complete set of vocabulary flashcards covering the anatomy, pathophysiology, diagnosis, and management of acute adrenal insufficiency and crisis based on the lecture transcript.

Zona Glomerulosa

The outer layer of the adrenal cortex that primarily produces aldosterone and some cortisol.

Zona Fasciculata

The middle layer of the adrenal cortex that exclusively produces cortisol.

Zona Reticularis

The inner layer of the adrenal cortex that produces androgens and some cortisol.

Adrenal Medulla

The inner part of the adrenal gland responsible for secreting catecholamines, specifically epinephrine, norepinephrine, and dopamine.

HPA Axis

The endocrine feedback system involving the Hypothalamus (releasing CRH), the Pituitary (releasing ACTH), and the Adrenal cortex (releasing Cortisol).

Primary Adrenal Insufficiency (Addison's disease)

Adrenal gland failure resulting in low cortisol and aldosterone levels alongside high ACTH levels.

Secondary Adrenal Insufficiency

Pituitary failure leading to low ACTH and low cortisol, while mineralocorticoid (aldosterone) production is generally preserved.

Tertiary Adrenal Insufficiency

Hypothalamic disease or chronic exogenous steroid use resulting in impaired CRH, low ACTH, and low cortisol.

Acute Adrenal Crisis (Addisonian Crisis)

A life-threatening emergency caused by a deficiency of adrenocortical hormones, often characterized by severe hypotension resistant to catecholamines and IVF resuscitation.

Hyperpigmentation

A clinical feature specific to primary adrenal insufficiency caused by elevated levels of ACTH and MSH (melanocortite-stimulating hormone).

Sheehan Syndrome

Post-partum pituitary necrosis that can lead to catastrophic HPA axis failure and secondary adrenocortical insufficiency.

Waterhouse-Friderichsen Syndrome

Adrenal failure caused by hemorrhage into the adrenal glands, often associated with serious infection.

Thyrotoxicosis

A condition that can trigger adrenal crisis by accelerating the metabolism of cortisol.

ACTH (Cosyntropin) Stimulation Test

The gold standard confirmatory test for adrenal insufficiency where cortisol is measured before and after the administration of $250\,\mu g$ of synthetic ACTH.

Normal Cortisol Response (Stimulation Test)

A rise in cortisol levels to greater than $18-20\,\mu g/dL$ after receiving synthetic ACTH.

8 AM Cortisol Screening

A diagnostic measurement where a level less than $3\,\mu g/dL$ strongly supports a diagnosis of adrenal insufficiency.

Initial Emergency Management Step (Medication)

The immediate IV or IM administration of $100\,mg$ of Hydrocortisone.

Maintenance Emergency Steroid Dose

Hydrocortisone provided as a continuous infusion of $200\,mg/24h$ or $50\,mg$ IV every $6$ hours.

Fludrocortisone

A mineralocorticoid replacement therapy used in primary adrenal insufficiency at doses of $0.05-0.2\,mg/day$.

Sick-day Rules

The education-based protocol instructing patients to double or triple their oral steroid dose during illness, accident, or significant stress.

21-hydroxylase antibodies

A laboratory marker used to screen for autoimmune adrenalitis, the most common cause of primary AI in developed countries.

Steroid Equivalence: Prednisone to Hydrocortisone

$5\,mg$ of Prednisone is equivalent to $20\,mg$ of Hydrocortisone.

Steroid Equivalence: Methylprednisolone to Prednisone

$4\,mg$ of Methylprednisolone is equivalent to $5\,mg$ of Prednisone.

Steroid Equivalence: Prednisone to Dexamethasone

$5\,mg$ of Prednisone is equivalent to $0.75\,mg$ of Dexamethasone.