Adrenal Problems

Zona glomerulosa: outer; aldosterone

Zona fascitulata: middle; cortisol

Zona reticularis: inner; androgens

Anatomy

CRH from hypothalamus ACTH from APG Cortisol from adrenal cortex

Effects of cortisol: release of CRH and ACTH

Gluconeogenesis, lipolysis

ketogenesis, insulin release BSL

effects of cytokines, cell mediated immunity, anti-inflammatory

RAA aldosterone from adrenal cortex

Effects of aldosterone: Na ( reabsorption), H20 excretion

K ( excretion) in DCT

alkalosis ( H excretion)

Pathophysiology

Cause: Iatrogenic (steroids, ACTH; most common cause)

Pituitary adenoma (Cushings disease)

Adrenal adenoma / cancer / hyperplasia

Ectopic CRH (eg. Pancreas, bronchial carcinoid, thymic cancer)

Ectopic ACTH (20%; eg. Oat cell cancer lung)

Examination: moon face, buffalo hump, truncal obesity, acne, striae, hursutism, atrophic skin,

osteoporosis, HTN, peri oedema, diabetes, psych (>70%), bitemporal hemianopia, adrenal cancer

If 2Y to ACTH no Cushingoid fetaures, but HTN, oedema, prox myopathy, hyperpigmentation, cachexia

Investigations: hyper HTN / glycaemia

Hypo K

Metabolic alkalosis

Hb, neutrophils

Cortisol: at 00:00; >200 = Cushings

24hr urinary cortisol: 85% sensitivity; false ive if dilute urine

Corticotropin

Dexamethasone suppression test: 24hr urine for 2/7; cortisol and ACTH blood test at

09:00; dexamethason 1mg given at 11pm; normal should be to